1 //===---- TargetInfo.cpp - Encapsulate target details -----------*- C++ -*-===//
2 //
3 //                     The LLVM Compiler Infrastructure
4 //
5 // This file is distributed under the University of Illinois Open Source
6 // License. See LICENSE.TXT for details.
7 //
8 //===----------------------------------------------------------------------===//
9 //
10 // These classes wrap the information about a call or function
11 // definition used to handle ABI compliancy.
12 //
13 //===----------------------------------------------------------------------===//
14 
15 #include "TargetInfo.h"
16 #include "ABIInfo.h"
17 #include "CGCXXABI.h"
18 #include "CGValue.h"
19 #include "CodeGenFunction.h"
20 #include "clang/AST/RecordLayout.h"
21 #include "clang/CodeGen/CGFunctionInfo.h"
22 #include "clang/Frontend/CodeGenOptions.h"
23 #include "llvm/ADT/StringExtras.h"
24 #include "llvm/ADT/Triple.h"
25 #include "llvm/IR/DataLayout.h"
26 #include "llvm/IR/Type.h"
27 #include "llvm/Support/raw_ostream.h"
28 #include <algorithm>    // std::sort
29 
30 using namespace clang;
31 using namespace CodeGen;
32 
33 static void AssignToArrayRange(CodeGen::CGBuilderTy &Builder,
34                                llvm::Value *Array,
35                                llvm::Value *Value,
36                                unsigned FirstIndex,
37                                unsigned LastIndex) {
38   // Alternatively, we could emit this as a loop in the source.
39   for (unsigned I = FirstIndex; I <= LastIndex; ++I) {
40     llvm::Value *Cell =
41         Builder.CreateConstInBoundsGEP1_32(Builder.getInt8Ty(), Array, I);
42     Builder.CreateAlignedStore(Value, Cell, CharUnits::One());
43   }
44 }
45 
46 static bool isAggregateTypeForABI(QualType T) {
47   return !CodeGenFunction::hasScalarEvaluationKind(T) ||
48          T->isMemberFunctionPointerType();
49 }
50 
51 ABIArgInfo
52 ABIInfo::getNaturalAlignIndirect(QualType Ty, bool ByRef, bool Realign,
53                                  llvm::Type *Padding) const {
54   return ABIArgInfo::getIndirect(getContext().getTypeAlignInChars(Ty),
55                                  ByRef, Realign, Padding);
56 }
57 
58 ABIArgInfo
59 ABIInfo::getNaturalAlignIndirectInReg(QualType Ty, bool Realign) const {
60   return ABIArgInfo::getIndirectInReg(getContext().getTypeAlignInChars(Ty),
61                                       /*ByRef*/ false, Realign);
62 }
63 
64 Address ABIInfo::EmitMSVAArg(CodeGenFunction &CGF, Address VAListAddr,
65                              QualType Ty) const {
66   return Address::invalid();
67 }
68 
69 ABIInfo::~ABIInfo() {}
70 
71 static CGCXXABI::RecordArgABI getRecordArgABI(const RecordType *RT,
72                                               CGCXXABI &CXXABI) {
73   const CXXRecordDecl *RD = dyn_cast<CXXRecordDecl>(RT->getDecl());
74   if (!RD)
75     return CGCXXABI::RAA_Default;
76   return CXXABI.getRecordArgABI(RD);
77 }
78 
79 static CGCXXABI::RecordArgABI getRecordArgABI(QualType T,
80                                               CGCXXABI &CXXABI) {
81   const RecordType *RT = T->getAs<RecordType>();
82   if (!RT)
83     return CGCXXABI::RAA_Default;
84   return getRecordArgABI(RT, CXXABI);
85 }
86 
87 /// Pass transparent unions as if they were the type of the first element. Sema
88 /// should ensure that all elements of the union have the same "machine type".
89 static QualType useFirstFieldIfTransparentUnion(QualType Ty) {
90   if (const RecordType *UT = Ty->getAsUnionType()) {
91     const RecordDecl *UD = UT->getDecl();
92     if (UD->hasAttr<TransparentUnionAttr>()) {
93       assert(!UD->field_empty() && "sema created an empty transparent union");
94       return UD->field_begin()->getType();
95     }
96   }
97   return Ty;
98 }
99 
100 CGCXXABI &ABIInfo::getCXXABI() const {
101   return CGT.getCXXABI();
102 }
103 
104 ASTContext &ABIInfo::getContext() const {
105   return CGT.getContext();
106 }
107 
108 llvm::LLVMContext &ABIInfo::getVMContext() const {
109   return CGT.getLLVMContext();
110 }
111 
112 const llvm::DataLayout &ABIInfo::getDataLayout() const {
113   return CGT.getDataLayout();
114 }
115 
116 const TargetInfo &ABIInfo::getTarget() const {
117   return CGT.getTarget();
118 }
119 
120 bool ABIInfo::isHomogeneousAggregateBaseType(QualType Ty) const {
121   return false;
122 }
123 
124 bool ABIInfo::isHomogeneousAggregateSmallEnough(const Type *Base,
125                                                 uint64_t Members) const {
126   return false;
127 }
128 
129 bool ABIInfo::shouldSignExtUnsignedType(QualType Ty) const {
130   return false;
131 }
132 
133 void ABIArgInfo::dump() const {
134   raw_ostream &OS = llvm::errs();
135   OS << "(ABIArgInfo Kind=";
136   switch (TheKind) {
137   case Direct:
138     OS << "Direct Type=";
139     if (llvm::Type *Ty = getCoerceToType())
140       Ty->print(OS);
141     else
142       OS << "null";
143     break;
144   case Extend:
145     OS << "Extend";
146     break;
147   case Ignore:
148     OS << "Ignore";
149     break;
150   case InAlloca:
151     OS << "InAlloca Offset=" << getInAllocaFieldIndex();
152     break;
153   case Indirect:
154     OS << "Indirect Align=" << getIndirectAlign().getQuantity()
155        << " ByVal=" << getIndirectByVal()
156        << " Realign=" << getIndirectRealign();
157     break;
158   case Expand:
159     OS << "Expand";
160     break;
161   }
162   OS << ")\n";
163 }
164 
165 /// Emit va_arg for a platform using the common void* representation,
166 /// where arguments are simply emitted in an array of slots on the stack.
167 ///
168 /// This version implements the core direct-value passing rules.
169 ///
170 /// \param SlotSize - The size and alignment of a stack slot.
171 ///   Each argument will be allocated to a multiple of this number of
172 ///   slots, and all the slots will be aligned to this value.
173 /// \param AllowHigherAlign - The slot alignment is not a cap;
174 ///   an argument type with an alignment greater than the slot size
175 ///   will be emitted on a higher-alignment address, potentially
176 ///   leaving one or more empty slots behind as padding.  If this
177 ///   is false, the returned address might be less-aligned than
178 ///   DirectAlign.
179 static Address emitVoidPtrDirectVAArg(CodeGenFunction &CGF,
180                                       Address VAListAddr,
181                                       llvm::Type *DirectTy,
182                                       CharUnits DirectSize,
183                                       CharUnits DirectAlign,
184                                       CharUnits SlotSize,
185                                       bool AllowHigherAlign) {
186   // Cast the element type to i8* if necessary.  Some platforms define
187   // va_list as a struct containing an i8* instead of just an i8*.
188   if (VAListAddr.getElementType() != CGF.Int8PtrTy)
189     VAListAddr = CGF.Builder.CreateElementBitCast(VAListAddr, CGF.Int8PtrTy);
190 
191   llvm::Value *Ptr = CGF.Builder.CreateLoad(VAListAddr, "argp.cur");
192 
193   // If the CC aligns values higher than the slot size, do so if needed.
194   Address Addr = Address::invalid();
195   if (AllowHigherAlign && DirectAlign > SlotSize) {
196     llvm::Value *PtrAsInt = Ptr;
197     PtrAsInt = CGF.Builder.CreatePtrToInt(PtrAsInt, CGF.IntPtrTy);
198     PtrAsInt = CGF.Builder.CreateAdd(PtrAsInt,
199           llvm::ConstantInt::get(CGF.IntPtrTy, DirectAlign.getQuantity() - 1));
200     PtrAsInt = CGF.Builder.CreateAnd(PtrAsInt,
201              llvm::ConstantInt::get(CGF.IntPtrTy, -DirectAlign.getQuantity()));
202     Addr = Address(CGF.Builder.CreateIntToPtr(PtrAsInt, Ptr->getType(),
203                                               "argp.cur.aligned"),
204                    DirectAlign);
205   } else {
206     Addr = Address(Ptr, SlotSize);
207   }
208 
209   // Advance the pointer past the argument, then store that back.
210   CharUnits FullDirectSize = DirectSize.RoundUpToAlignment(SlotSize);
211   llvm::Value *NextPtr =
212     CGF.Builder.CreateConstInBoundsByteGEP(Addr.getPointer(), FullDirectSize,
213                                            "argp.next");
214   CGF.Builder.CreateStore(NextPtr, VAListAddr);
215 
216   // If the argument is smaller than a slot, and this is a big-endian
217   // target, the argument will be right-adjusted in its slot.
218   if (DirectSize < SlotSize && CGF.CGM.getDataLayout().isBigEndian()) {
219     Addr = CGF.Builder.CreateConstInBoundsByteGEP(Addr, SlotSize - DirectSize);
220   }
221 
222   Addr = CGF.Builder.CreateElementBitCast(Addr, DirectTy);
223   return Addr;
224 }
225 
226 /// Emit va_arg for a platform using the common void* representation,
227 /// where arguments are simply emitted in an array of slots on the stack.
228 ///
229 /// \param IsIndirect - Values of this type are passed indirectly.
230 /// \param ValueInfo - The size and alignment of this type, generally
231 ///   computed with getContext().getTypeInfoInChars(ValueTy).
232 /// \param SlotSizeAndAlign - The size and alignment of a stack slot.
233 ///   Each argument will be allocated to a multiple of this number of
234 ///   slots, and all the slots will be aligned to this value.
235 /// \param AllowHigherAlign - The slot alignment is not a cap;
236 ///   an argument type with an alignment greater than the slot size
237 ///   will be emitted on a higher-alignment address, potentially
238 ///   leaving one or more empty slots behind as padding.
239 static Address emitVoidPtrVAArg(CodeGenFunction &CGF, Address VAListAddr,
240                                 QualType ValueTy, bool IsIndirect,
241                                 std::pair<CharUnits, CharUnits> ValueInfo,
242                                 CharUnits SlotSizeAndAlign,
243                                 bool AllowHigherAlign) {
244   // The size and alignment of the value that was passed directly.
245   CharUnits DirectSize, DirectAlign;
246   if (IsIndirect) {
247     DirectSize = CGF.getPointerSize();
248     DirectAlign = CGF.getPointerAlign();
249   } else {
250     DirectSize = ValueInfo.first;
251     DirectAlign = ValueInfo.second;
252   }
253 
254   // Cast the address we've calculated to the right type.
255   llvm::Type *DirectTy = CGF.ConvertTypeForMem(ValueTy);
256   if (IsIndirect)
257     DirectTy = DirectTy->getPointerTo(0);
258 
259   Address Addr = emitVoidPtrDirectVAArg(CGF, VAListAddr, DirectTy,
260                                         DirectSize, DirectAlign,
261                                         SlotSizeAndAlign,
262                                         AllowHigherAlign);
263 
264   if (IsIndirect) {
265     Addr = Address(CGF.Builder.CreateLoad(Addr), ValueInfo.second);
266   }
267 
268   return Addr;
269 
270 }
271 
272 static Address emitMergePHI(CodeGenFunction &CGF,
273                             Address Addr1, llvm::BasicBlock *Block1,
274                             Address Addr2, llvm::BasicBlock *Block2,
275                             const llvm::Twine &Name = "") {
276   assert(Addr1.getType() == Addr2.getType());
277   llvm::PHINode *PHI = CGF.Builder.CreatePHI(Addr1.getType(), 2, Name);
278   PHI->addIncoming(Addr1.getPointer(), Block1);
279   PHI->addIncoming(Addr2.getPointer(), Block2);
280   CharUnits Align = std::min(Addr1.getAlignment(), Addr2.getAlignment());
281   return Address(PHI, Align);
282 }
283 
284 TargetCodeGenInfo::~TargetCodeGenInfo() { delete Info; }
285 
286 // If someone can figure out a general rule for this, that would be great.
287 // It's probably just doomed to be platform-dependent, though.
288 unsigned TargetCodeGenInfo::getSizeOfUnwindException() const {
289   // Verified for:
290   //   x86-64     FreeBSD, Linux, Darwin
291   //   x86-32     FreeBSD, Linux, Darwin
292   //   PowerPC    Linux, Darwin
293   //   ARM        Darwin (*not* EABI)
294   //   AArch64    Linux
295   return 32;
296 }
297 
298 bool TargetCodeGenInfo::isNoProtoCallVariadic(const CallArgList &args,
299                                      const FunctionNoProtoType *fnType) const {
300   // The following conventions are known to require this to be false:
301   //   x86_stdcall
302   //   MIPS
303   // For everything else, we just prefer false unless we opt out.
304   return false;
305 }
306 
307 void
308 TargetCodeGenInfo::getDependentLibraryOption(llvm::StringRef Lib,
309                                              llvm::SmallString<24> &Opt) const {
310   // This assumes the user is passing a library name like "rt" instead of a
311   // filename like "librt.a/so", and that they don't care whether it's static or
312   // dynamic.
313   Opt = "-l";
314   Opt += Lib;
315 }
316 
317 static bool isEmptyRecord(ASTContext &Context, QualType T, bool AllowArrays);
318 
319 /// isEmptyField - Return true iff a the field is "empty", that is it
320 /// is an unnamed bit-field or an (array of) empty record(s).
321 static bool isEmptyField(ASTContext &Context, const FieldDecl *FD,
322                          bool AllowArrays) {
323   if (FD->isUnnamedBitfield())
324     return true;
325 
326   QualType FT = FD->getType();
327 
328   // Constant arrays of empty records count as empty, strip them off.
329   // Constant arrays of zero length always count as empty.
330   if (AllowArrays)
331     while (const ConstantArrayType *AT = Context.getAsConstantArrayType(FT)) {
332       if (AT->getSize() == 0)
333         return true;
334       FT = AT->getElementType();
335     }
336 
337   const RecordType *RT = FT->getAs<RecordType>();
338   if (!RT)
339     return false;
340 
341   // C++ record fields are never empty, at least in the Itanium ABI.
342   //
343   // FIXME: We should use a predicate for whether this behavior is true in the
344   // current ABI.
345   if (isa<CXXRecordDecl>(RT->getDecl()))
346     return false;
347 
348   return isEmptyRecord(Context, FT, AllowArrays);
349 }
350 
351 /// isEmptyRecord - Return true iff a structure contains only empty
352 /// fields. Note that a structure with a flexible array member is not
353 /// considered empty.
354 static bool isEmptyRecord(ASTContext &Context, QualType T, bool AllowArrays) {
355   const RecordType *RT = T->getAs<RecordType>();
356   if (!RT)
357     return 0;
358   const RecordDecl *RD = RT->getDecl();
359   if (RD->hasFlexibleArrayMember())
360     return false;
361 
362   // If this is a C++ record, check the bases first.
363   if (const CXXRecordDecl *CXXRD = dyn_cast<CXXRecordDecl>(RD))
364     for (const auto &I : CXXRD->bases())
365       if (!isEmptyRecord(Context, I.getType(), true))
366         return false;
367 
368   for (const auto *I : RD->fields())
369     if (!isEmptyField(Context, I, AllowArrays))
370       return false;
371   return true;
372 }
373 
374 /// isSingleElementStruct - Determine if a structure is a "single
375 /// element struct", i.e. it has exactly one non-empty field or
376 /// exactly one field which is itself a single element
377 /// struct. Structures with flexible array members are never
378 /// considered single element structs.
379 ///
380 /// \return The field declaration for the single non-empty field, if
381 /// it exists.
382 static const Type *isSingleElementStruct(QualType T, ASTContext &Context) {
383   const RecordType *RT = T->getAs<RecordType>();
384   if (!RT)
385     return nullptr;
386 
387   const RecordDecl *RD = RT->getDecl();
388   if (RD->hasFlexibleArrayMember())
389     return nullptr;
390 
391   const Type *Found = nullptr;
392 
393   // If this is a C++ record, check the bases first.
394   if (const CXXRecordDecl *CXXRD = dyn_cast<CXXRecordDecl>(RD)) {
395     for (const auto &I : CXXRD->bases()) {
396       // Ignore empty records.
397       if (isEmptyRecord(Context, I.getType(), true))
398         continue;
399 
400       // If we already found an element then this isn't a single-element struct.
401       if (Found)
402         return nullptr;
403 
404       // If this is non-empty and not a single element struct, the composite
405       // cannot be a single element struct.
406       Found = isSingleElementStruct(I.getType(), Context);
407       if (!Found)
408         return nullptr;
409     }
410   }
411 
412   // Check for single element.
413   for (const auto *FD : RD->fields()) {
414     QualType FT = FD->getType();
415 
416     // Ignore empty fields.
417     if (isEmptyField(Context, FD, true))
418       continue;
419 
420     // If we already found an element then this isn't a single-element
421     // struct.
422     if (Found)
423       return nullptr;
424 
425     // Treat single element arrays as the element.
426     while (const ConstantArrayType *AT = Context.getAsConstantArrayType(FT)) {
427       if (AT->getSize().getZExtValue() != 1)
428         break;
429       FT = AT->getElementType();
430     }
431 
432     if (!isAggregateTypeForABI(FT)) {
433       Found = FT.getTypePtr();
434     } else {
435       Found = isSingleElementStruct(FT, Context);
436       if (!Found)
437         return nullptr;
438     }
439   }
440 
441   // We don't consider a struct a single-element struct if it has
442   // padding beyond the element type.
443   if (Found && Context.getTypeSize(Found) != Context.getTypeSize(T))
444     return nullptr;
445 
446   return Found;
447 }
448 
449 static bool is32Or64BitBasicType(QualType Ty, ASTContext &Context) {
450   // Treat complex types as the element type.
451   if (const ComplexType *CTy = Ty->getAs<ComplexType>())
452     Ty = CTy->getElementType();
453 
454   // Check for a type which we know has a simple scalar argument-passing
455   // convention without any padding.  (We're specifically looking for 32
456   // and 64-bit integer and integer-equivalents, float, and double.)
457   if (!Ty->getAs<BuiltinType>() && !Ty->hasPointerRepresentation() &&
458       !Ty->isEnumeralType() && !Ty->isBlockPointerType())
459     return false;
460 
461   uint64_t Size = Context.getTypeSize(Ty);
462   return Size == 32 || Size == 64;
463 }
464 
465 /// canExpandIndirectArgument - Test whether an argument type which is to be
466 /// passed indirectly (on the stack) would have the equivalent layout if it was
467 /// expanded into separate arguments. If so, we prefer to do the latter to avoid
468 /// inhibiting optimizations.
469 ///
470 // FIXME: This predicate is missing many cases, currently it just follows
471 // llvm-gcc (checks that all fields are 32-bit or 64-bit primitive types). We
472 // should probably make this smarter, or better yet make the LLVM backend
473 // capable of handling it.
474 static bool canExpandIndirectArgument(QualType Ty, ASTContext &Context) {
475   // We can only expand structure types.
476   const RecordType *RT = Ty->getAs<RecordType>();
477   if (!RT)
478     return false;
479 
480   // We can only expand (C) structures.
481   //
482   // FIXME: This needs to be generalized to handle classes as well.
483   const RecordDecl *RD = RT->getDecl();
484   if (!RD->isStruct())
485     return false;
486 
487   // We try to expand CLike CXXRecordDecl.
488   if (const CXXRecordDecl *CXXRD = dyn_cast<CXXRecordDecl>(RD)) {
489     if (!CXXRD->isCLike())
490       return false;
491   }
492 
493   uint64_t Size = 0;
494 
495   for (const auto *FD : RD->fields()) {
496     if (!is32Or64BitBasicType(FD->getType(), Context))
497       return false;
498 
499     // FIXME: Reject bit-fields wholesale; there are two problems, we don't know
500     // how to expand them yet, and the predicate for telling if a bitfield still
501     // counts as "basic" is more complicated than what we were doing previously.
502     if (FD->isBitField())
503       return false;
504 
505     Size += Context.getTypeSize(FD->getType());
506   }
507 
508   // Make sure there are not any holes in the struct.
509   if (Size != Context.getTypeSize(Ty))
510     return false;
511 
512   return true;
513 }
514 
515 namespace {
516 /// DefaultABIInfo - The default implementation for ABI specific
517 /// details. This implementation provides information which results in
518 /// self-consistent and sensible LLVM IR generation, but does not
519 /// conform to any particular ABI.
520 class DefaultABIInfo : public ABIInfo {
521 public:
522   DefaultABIInfo(CodeGen::CodeGenTypes &CGT) : ABIInfo(CGT) {}
523 
524   ABIArgInfo classifyReturnType(QualType RetTy) const;
525   ABIArgInfo classifyArgumentType(QualType RetTy) const;
526 
527   void computeInfo(CGFunctionInfo &FI) const override {
528     if (!getCXXABI().classifyReturnType(FI))
529       FI.getReturnInfo() = classifyReturnType(FI.getReturnType());
530     for (auto &I : FI.arguments())
531       I.info = classifyArgumentType(I.type);
532   }
533 
534   Address EmitVAArg(CodeGenFunction &CGF, Address VAListAddr,
535                     QualType Ty) const override;
536 };
537 
538 class DefaultTargetCodeGenInfo : public TargetCodeGenInfo {
539 public:
540   DefaultTargetCodeGenInfo(CodeGen::CodeGenTypes &CGT)
541     : TargetCodeGenInfo(new DefaultABIInfo(CGT)) {}
542 };
543 
544 Address DefaultABIInfo::EmitVAArg(CodeGenFunction &CGF, Address VAListAddr,
545                                   QualType Ty) const {
546   return Address::invalid();
547 }
548 
549 ABIArgInfo DefaultABIInfo::classifyArgumentType(QualType Ty) const {
550   Ty = useFirstFieldIfTransparentUnion(Ty);
551 
552   if (isAggregateTypeForABI(Ty)) {
553     // Records with non-trivial destructors/copy-constructors should not be
554     // passed by value.
555     if (CGCXXABI::RecordArgABI RAA = getRecordArgABI(Ty, getCXXABI()))
556       return getNaturalAlignIndirect(Ty, RAA == CGCXXABI::RAA_DirectInMemory);
557 
558     return getNaturalAlignIndirect(Ty);
559   }
560 
561   // Treat an enum type as its underlying type.
562   if (const EnumType *EnumTy = Ty->getAs<EnumType>())
563     Ty = EnumTy->getDecl()->getIntegerType();
564 
565   return (Ty->isPromotableIntegerType() ?
566           ABIArgInfo::getExtend() : ABIArgInfo::getDirect());
567 }
568 
569 ABIArgInfo DefaultABIInfo::classifyReturnType(QualType RetTy) const {
570   if (RetTy->isVoidType())
571     return ABIArgInfo::getIgnore();
572 
573   if (isAggregateTypeForABI(RetTy))
574     return getNaturalAlignIndirect(RetTy);
575 
576   // Treat an enum type as its underlying type.
577   if (const EnumType *EnumTy = RetTy->getAs<EnumType>())
578     RetTy = EnumTy->getDecl()->getIntegerType();
579 
580   return (RetTy->isPromotableIntegerType() ?
581           ABIArgInfo::getExtend() : ABIArgInfo::getDirect());
582 }
583 
584 //===----------------------------------------------------------------------===//
585 // WebAssembly ABI Implementation
586 //
587 // This is a very simple ABI that relies a lot on DefaultABIInfo.
588 //===----------------------------------------------------------------------===//
589 
590 class WebAssemblyABIInfo final : public DefaultABIInfo {
591 public:
592   explicit WebAssemblyABIInfo(CodeGen::CodeGenTypes &CGT)
593       : DefaultABIInfo(CGT) {}
594 
595 private:
596   ABIArgInfo classifyReturnType(QualType RetTy) const;
597   ABIArgInfo classifyArgumentType(QualType Ty) const;
598 
599   // DefaultABIInfo's classifyReturnType and classifyArgumentType are
600   // non-virtual, but computeInfo is virtual, so we overload that.
601   void computeInfo(CGFunctionInfo &FI) const override {
602     if (!getCXXABI().classifyReturnType(FI))
603       FI.getReturnInfo() = classifyReturnType(FI.getReturnType());
604     for (auto &Arg : FI.arguments())
605       Arg.info = classifyArgumentType(Arg.type);
606   }
607 };
608 
609 class WebAssemblyTargetCodeGenInfo final : public TargetCodeGenInfo {
610 public:
611   explicit WebAssemblyTargetCodeGenInfo(CodeGen::CodeGenTypes &CGT)
612       : TargetCodeGenInfo(new WebAssemblyABIInfo(CGT)) {}
613 };
614 
615 /// \brief Classify argument of given type \p Ty.
616 ABIArgInfo WebAssemblyABIInfo::classifyArgumentType(QualType Ty) const {
617   Ty = useFirstFieldIfTransparentUnion(Ty);
618 
619   if (isAggregateTypeForABI(Ty)) {
620     // Records with non-trivial destructors/copy-constructors should not be
621     // passed by value.
622     if (auto RAA = getRecordArgABI(Ty, getCXXABI()))
623       return getNaturalAlignIndirect(Ty, RAA == CGCXXABI::RAA_DirectInMemory);
624     // Ignore empty structs/unions.
625     if (isEmptyRecord(getContext(), Ty, true))
626       return ABIArgInfo::getIgnore();
627     // Lower single-element structs to just pass a regular value. TODO: We
628     // could do reasonable-size multiple-element structs too, using getExpand(),
629     // though watch out for things like bitfields.
630     if (const Type *SeltTy = isSingleElementStruct(Ty, getContext()))
631       return ABIArgInfo::getDirect(CGT.ConvertType(QualType(SeltTy, 0)));
632   }
633 
634   // Otherwise just do the default thing.
635   return DefaultABIInfo::classifyArgumentType(Ty);
636 }
637 
638 ABIArgInfo WebAssemblyABIInfo::classifyReturnType(QualType RetTy) const {
639   if (isAggregateTypeForABI(RetTy)) {
640     // Records with non-trivial destructors/copy-constructors should not be
641     // returned by value.
642     if (!getRecordArgABI(RetTy, getCXXABI())) {
643       // Ignore empty structs/unions.
644       if (isEmptyRecord(getContext(), RetTy, true))
645         return ABIArgInfo::getIgnore();
646       // Lower single-element structs to just return a regular value. TODO: We
647       // could do reasonable-size multiple-element structs too, using
648       // ABIArgInfo::getDirect().
649       if (const Type *SeltTy = isSingleElementStruct(RetTy, getContext()))
650         return ABIArgInfo::getDirect(CGT.ConvertType(QualType(SeltTy, 0)));
651     }
652   }
653 
654   // Otherwise just do the default thing.
655   return DefaultABIInfo::classifyReturnType(RetTy);
656 }
657 
658 //===----------------------------------------------------------------------===//
659 // le32/PNaCl bitcode ABI Implementation
660 //
661 // This is a simplified version of the x86_32 ABI.  Arguments and return values
662 // are always passed on the stack.
663 //===----------------------------------------------------------------------===//
664 
665 class PNaClABIInfo : public ABIInfo {
666  public:
667   PNaClABIInfo(CodeGen::CodeGenTypes &CGT) : ABIInfo(CGT) {}
668 
669   ABIArgInfo classifyReturnType(QualType RetTy) const;
670   ABIArgInfo classifyArgumentType(QualType RetTy) const;
671 
672   void computeInfo(CGFunctionInfo &FI) const override;
673   Address EmitVAArg(CodeGenFunction &CGF,
674                     Address VAListAddr, QualType Ty) const override;
675 };
676 
677 class PNaClTargetCodeGenInfo : public TargetCodeGenInfo {
678  public:
679   PNaClTargetCodeGenInfo(CodeGen::CodeGenTypes &CGT)
680     : TargetCodeGenInfo(new PNaClABIInfo(CGT)) {}
681 };
682 
683 void PNaClABIInfo::computeInfo(CGFunctionInfo &FI) const {
684   if (!getCXXABI().classifyReturnType(FI))
685     FI.getReturnInfo() = classifyReturnType(FI.getReturnType());
686 
687   for (auto &I : FI.arguments())
688     I.info = classifyArgumentType(I.type);
689 }
690 
691 Address PNaClABIInfo::EmitVAArg(CodeGenFunction &CGF, Address VAListAddr,
692                                 QualType Ty) const {
693   return Address::invalid();
694 }
695 
696 /// \brief Classify argument of given type \p Ty.
697 ABIArgInfo PNaClABIInfo::classifyArgumentType(QualType Ty) const {
698   if (isAggregateTypeForABI(Ty)) {
699     if (CGCXXABI::RecordArgABI RAA = getRecordArgABI(Ty, getCXXABI()))
700       return getNaturalAlignIndirect(Ty, RAA == CGCXXABI::RAA_DirectInMemory);
701     return getNaturalAlignIndirect(Ty);
702   } else if (const EnumType *EnumTy = Ty->getAs<EnumType>()) {
703     // Treat an enum type as its underlying type.
704     Ty = EnumTy->getDecl()->getIntegerType();
705   } else if (Ty->isFloatingType()) {
706     // Floating-point types don't go inreg.
707     return ABIArgInfo::getDirect();
708   }
709 
710   return (Ty->isPromotableIntegerType() ?
711           ABIArgInfo::getExtend() : ABIArgInfo::getDirect());
712 }
713 
714 ABIArgInfo PNaClABIInfo::classifyReturnType(QualType RetTy) const {
715   if (RetTy->isVoidType())
716     return ABIArgInfo::getIgnore();
717 
718   // In the PNaCl ABI we always return records/structures on the stack.
719   if (isAggregateTypeForABI(RetTy))
720     return getNaturalAlignIndirect(RetTy);
721 
722   // Treat an enum type as its underlying type.
723   if (const EnumType *EnumTy = RetTy->getAs<EnumType>())
724     RetTy = EnumTy->getDecl()->getIntegerType();
725 
726   return (RetTy->isPromotableIntegerType() ?
727           ABIArgInfo::getExtend() : ABIArgInfo::getDirect());
728 }
729 
730 /// IsX86_MMXType - Return true if this is an MMX type.
731 bool IsX86_MMXType(llvm::Type *IRType) {
732   // Return true if the type is an MMX type <2 x i32>, <4 x i16>, or <8 x i8>.
733   return IRType->isVectorTy() && IRType->getPrimitiveSizeInBits() == 64 &&
734     cast<llvm::VectorType>(IRType)->getElementType()->isIntegerTy() &&
735     IRType->getScalarSizeInBits() != 64;
736 }
737 
738 static llvm::Type* X86AdjustInlineAsmType(CodeGen::CodeGenFunction &CGF,
739                                           StringRef Constraint,
740                                           llvm::Type* Ty) {
741   if ((Constraint == "y" || Constraint == "&y") && Ty->isVectorTy()) {
742     if (cast<llvm::VectorType>(Ty)->getBitWidth() != 64) {
743       // Invalid MMX constraint
744       return nullptr;
745     }
746 
747     return llvm::Type::getX86_MMXTy(CGF.getLLVMContext());
748   }
749 
750   // No operation needed
751   return Ty;
752 }
753 
754 /// Returns true if this type can be passed in SSE registers with the
755 /// X86_VectorCall calling convention. Shared between x86_32 and x86_64.
756 static bool isX86VectorTypeForVectorCall(ASTContext &Context, QualType Ty) {
757   if (const BuiltinType *BT = Ty->getAs<BuiltinType>()) {
758     if (BT->isFloatingPoint() && BT->getKind() != BuiltinType::Half)
759       return true;
760   } else if (const VectorType *VT = Ty->getAs<VectorType>()) {
761     // vectorcall can pass XMM, YMM, and ZMM vectors. We don't pass SSE1 MMX
762     // registers specially.
763     unsigned VecSize = Context.getTypeSize(VT);
764     if (VecSize == 128 || VecSize == 256 || VecSize == 512)
765       return true;
766   }
767   return false;
768 }
769 
770 /// Returns true if this aggregate is small enough to be passed in SSE registers
771 /// in the X86_VectorCall calling convention. Shared between x86_32 and x86_64.
772 static bool isX86VectorCallAggregateSmallEnough(uint64_t NumMembers) {
773   return NumMembers <= 4;
774 }
775 
776 //===----------------------------------------------------------------------===//
777 // X86-32 ABI Implementation
778 //===----------------------------------------------------------------------===//
779 
780 /// \brief Similar to llvm::CCState, but for Clang.
781 struct CCState {
782   CCState(unsigned CC) : CC(CC), FreeRegs(0), FreeSSERegs(0) {}
783 
784   unsigned CC;
785   unsigned FreeRegs;
786   unsigned FreeSSERegs;
787 };
788 
789 /// X86_32ABIInfo - The X86-32 ABI information.
790 class X86_32ABIInfo : public ABIInfo {
791   enum Class {
792     Integer,
793     Float
794   };
795 
796   static const unsigned MinABIStackAlignInBytes = 4;
797 
798   bool IsDarwinVectorABI;
799   bool IsRetSmallStructInRegABI;
800   bool IsWin32StructABI;
801   bool IsSoftFloatABI;
802   unsigned DefaultNumRegisterParameters;
803 
804   static bool isRegisterSize(unsigned Size) {
805     return (Size == 8 || Size == 16 || Size == 32 || Size == 64);
806   }
807 
808   bool isHomogeneousAggregateBaseType(QualType Ty) const override {
809     // FIXME: Assumes vectorcall is in use.
810     return isX86VectorTypeForVectorCall(getContext(), Ty);
811   }
812 
813   bool isHomogeneousAggregateSmallEnough(const Type *Ty,
814                                          uint64_t NumMembers) const override {
815     // FIXME: Assumes vectorcall is in use.
816     return isX86VectorCallAggregateSmallEnough(NumMembers);
817   }
818 
819   bool shouldReturnTypeInRegister(QualType Ty, ASTContext &Context) const;
820 
821   /// getIndirectResult - Give a source type \arg Ty, return a suitable result
822   /// such that the argument will be passed in memory.
823   ABIArgInfo getIndirectResult(QualType Ty, bool ByVal, CCState &State) const;
824 
825   ABIArgInfo getIndirectReturnResult(QualType Ty, CCState &State) const;
826 
827   /// \brief Return the alignment to use for the given type on the stack.
828   unsigned getTypeStackAlignInBytes(QualType Ty, unsigned Align) const;
829 
830   Class classify(QualType Ty) const;
831   ABIArgInfo classifyReturnType(QualType RetTy, CCState &State) const;
832   ABIArgInfo classifyArgumentType(QualType RetTy, CCState &State) const;
833   bool shouldUseInReg(QualType Ty, CCState &State, bool &NeedsPadding) const;
834 
835   /// \brief Rewrite the function info so that all memory arguments use
836   /// inalloca.
837   void rewriteWithInAlloca(CGFunctionInfo &FI) const;
838 
839   void addFieldToArgStruct(SmallVector<llvm::Type *, 6> &FrameFields,
840                            CharUnits &StackOffset, ABIArgInfo &Info,
841                            QualType Type) const;
842 
843 public:
844 
845   void computeInfo(CGFunctionInfo &FI) const override;
846   Address EmitVAArg(CodeGenFunction &CGF, Address VAListAddr,
847                     QualType Ty) const override;
848 
849   X86_32ABIInfo(CodeGen::CodeGenTypes &CGT, bool DarwinVectorABI,
850                 bool RetSmallStructInRegABI, bool Win32StructABI,
851                 unsigned NumRegisterParameters, bool SoftFloatABI)
852     : ABIInfo(CGT), IsDarwinVectorABI(DarwinVectorABI),
853       IsRetSmallStructInRegABI(RetSmallStructInRegABI),
854       IsWin32StructABI(Win32StructABI),
855       IsSoftFloatABI(SoftFloatABI),
856       DefaultNumRegisterParameters(NumRegisterParameters) {}
857 };
858 
859 class X86_32TargetCodeGenInfo : public TargetCodeGenInfo {
860 public:
861   X86_32TargetCodeGenInfo(CodeGen::CodeGenTypes &CGT, bool DarwinVectorABI,
862                           bool RetSmallStructInRegABI, bool Win32StructABI,
863                           unsigned NumRegisterParameters, bool SoftFloatABI)
864       : TargetCodeGenInfo(new X86_32ABIInfo(
865             CGT, DarwinVectorABI, RetSmallStructInRegABI, Win32StructABI,
866             NumRegisterParameters, SoftFloatABI)) {}
867 
868   static bool isStructReturnInRegABI(
869       const llvm::Triple &Triple, const CodeGenOptions &Opts);
870 
871   void setTargetAttributes(const Decl *D, llvm::GlobalValue *GV,
872                            CodeGen::CodeGenModule &CGM) const override;
873 
874   int getDwarfEHStackPointer(CodeGen::CodeGenModule &CGM) const override {
875     // Darwin uses different dwarf register numbers for EH.
876     if (CGM.getTarget().getTriple().isOSDarwin()) return 5;
877     return 4;
878   }
879 
880   bool initDwarfEHRegSizeTable(CodeGen::CodeGenFunction &CGF,
881                                llvm::Value *Address) const override;
882 
883   llvm::Type* adjustInlineAsmType(CodeGen::CodeGenFunction &CGF,
884                                   StringRef Constraint,
885                                   llvm::Type* Ty) const override {
886     return X86AdjustInlineAsmType(CGF, Constraint, Ty);
887   }
888 
889   void addReturnRegisterOutputs(CodeGenFunction &CGF, LValue ReturnValue,
890                                 std::string &Constraints,
891                                 std::vector<llvm::Type *> &ResultRegTypes,
892                                 std::vector<llvm::Type *> &ResultTruncRegTypes,
893                                 std::vector<LValue> &ResultRegDests,
894                                 std::string &AsmString,
895                                 unsigned NumOutputs) const override;
896 
897   llvm::Constant *
898   getUBSanFunctionSignature(CodeGen::CodeGenModule &CGM) const override {
899     unsigned Sig = (0xeb << 0) |  // jmp rel8
900                    (0x06 << 8) |  //           .+0x08
901                    ('F' << 16) |
902                    ('T' << 24);
903     return llvm::ConstantInt::get(CGM.Int32Ty, Sig);
904   }
905 };
906 
907 }
908 
909 /// Rewrite input constraint references after adding some output constraints.
910 /// In the case where there is one output and one input and we add one output,
911 /// we need to replace all operand references greater than or equal to 1:
912 ///     mov $0, $1
913 ///     mov eax, $1
914 /// The result will be:
915 ///     mov $0, $2
916 ///     mov eax, $2
917 static void rewriteInputConstraintReferences(unsigned FirstIn,
918                                              unsigned NumNewOuts,
919                                              std::string &AsmString) {
920   std::string Buf;
921   llvm::raw_string_ostream OS(Buf);
922   size_t Pos = 0;
923   while (Pos < AsmString.size()) {
924     size_t DollarStart = AsmString.find('$', Pos);
925     if (DollarStart == std::string::npos)
926       DollarStart = AsmString.size();
927     size_t DollarEnd = AsmString.find_first_not_of('$', DollarStart);
928     if (DollarEnd == std::string::npos)
929       DollarEnd = AsmString.size();
930     OS << StringRef(&AsmString[Pos], DollarEnd - Pos);
931     Pos = DollarEnd;
932     size_t NumDollars = DollarEnd - DollarStart;
933     if (NumDollars % 2 != 0 && Pos < AsmString.size()) {
934       // We have an operand reference.
935       size_t DigitStart = Pos;
936       size_t DigitEnd = AsmString.find_first_not_of("0123456789", DigitStart);
937       if (DigitEnd == std::string::npos)
938         DigitEnd = AsmString.size();
939       StringRef OperandStr(&AsmString[DigitStart], DigitEnd - DigitStart);
940       unsigned OperandIndex;
941       if (!OperandStr.getAsInteger(10, OperandIndex)) {
942         if (OperandIndex >= FirstIn)
943           OperandIndex += NumNewOuts;
944         OS << OperandIndex;
945       } else {
946         OS << OperandStr;
947       }
948       Pos = DigitEnd;
949     }
950   }
951   AsmString = std::move(OS.str());
952 }
953 
954 /// Add output constraints for EAX:EDX because they are return registers.
955 void X86_32TargetCodeGenInfo::addReturnRegisterOutputs(
956     CodeGenFunction &CGF, LValue ReturnSlot, std::string &Constraints,
957     std::vector<llvm::Type *> &ResultRegTypes,
958     std::vector<llvm::Type *> &ResultTruncRegTypes,
959     std::vector<LValue> &ResultRegDests, std::string &AsmString,
960     unsigned NumOutputs) const {
961   uint64_t RetWidth = CGF.getContext().getTypeSize(ReturnSlot.getType());
962 
963   // Use the EAX constraint if the width is 32 or smaller and EAX:EDX if it is
964   // larger.
965   if (!Constraints.empty())
966     Constraints += ',';
967   if (RetWidth <= 32) {
968     Constraints += "={eax}";
969     ResultRegTypes.push_back(CGF.Int32Ty);
970   } else {
971     // Use the 'A' constraint for EAX:EDX.
972     Constraints += "=A";
973     ResultRegTypes.push_back(CGF.Int64Ty);
974   }
975 
976   // Truncate EAX or EAX:EDX to an integer of the appropriate size.
977   llvm::Type *CoerceTy = llvm::IntegerType::get(CGF.getLLVMContext(), RetWidth);
978   ResultTruncRegTypes.push_back(CoerceTy);
979 
980   // Coerce the integer by bitcasting the return slot pointer.
981   ReturnSlot.setAddress(CGF.Builder.CreateBitCast(ReturnSlot.getAddress(),
982                                                   CoerceTy->getPointerTo()));
983   ResultRegDests.push_back(ReturnSlot);
984 
985   rewriteInputConstraintReferences(NumOutputs, 1, AsmString);
986 }
987 
988 /// shouldReturnTypeInRegister - Determine if the given type should be
989 /// returned in a register (for the Darwin ABI).
990 bool X86_32ABIInfo::shouldReturnTypeInRegister(QualType Ty,
991                                                ASTContext &Context) const {
992   uint64_t Size = Context.getTypeSize(Ty);
993 
994   // Type must be register sized.
995   if (!isRegisterSize(Size))
996     return false;
997 
998   if (Ty->isVectorType()) {
999     // 64- and 128- bit vectors inside structures are not returned in
1000     // registers.
1001     if (Size == 64 || Size == 128)
1002       return false;
1003 
1004     return true;
1005   }
1006 
1007   // If this is a builtin, pointer, enum, complex type, member pointer, or
1008   // member function pointer it is ok.
1009   if (Ty->getAs<BuiltinType>() || Ty->hasPointerRepresentation() ||
1010       Ty->isAnyComplexType() || Ty->isEnumeralType() ||
1011       Ty->isBlockPointerType() || Ty->isMemberPointerType())
1012     return true;
1013 
1014   // Arrays are treated like records.
1015   if (const ConstantArrayType *AT = Context.getAsConstantArrayType(Ty))
1016     return shouldReturnTypeInRegister(AT->getElementType(), Context);
1017 
1018   // Otherwise, it must be a record type.
1019   const RecordType *RT = Ty->getAs<RecordType>();
1020   if (!RT) return false;
1021 
1022   // FIXME: Traverse bases here too.
1023 
1024   // Structure types are passed in register if all fields would be
1025   // passed in a register.
1026   for (const auto *FD : RT->getDecl()->fields()) {
1027     // Empty fields are ignored.
1028     if (isEmptyField(Context, FD, true))
1029       continue;
1030 
1031     // Check fields recursively.
1032     if (!shouldReturnTypeInRegister(FD->getType(), Context))
1033       return false;
1034   }
1035   return true;
1036 }
1037 
1038 ABIArgInfo X86_32ABIInfo::getIndirectReturnResult(QualType RetTy, CCState &State) const {
1039   // If the return value is indirect, then the hidden argument is consuming one
1040   // integer register.
1041   if (State.FreeRegs) {
1042     --State.FreeRegs;
1043     return getNaturalAlignIndirectInReg(RetTy);
1044   }
1045   return getNaturalAlignIndirect(RetTy, /*ByVal=*/false);
1046 }
1047 
1048 ABIArgInfo X86_32ABIInfo::classifyReturnType(QualType RetTy,
1049                                              CCState &State) const {
1050   if (RetTy->isVoidType())
1051     return ABIArgInfo::getIgnore();
1052 
1053   const Type *Base = nullptr;
1054   uint64_t NumElts = 0;
1055   if (State.CC == llvm::CallingConv::X86_VectorCall &&
1056       isHomogeneousAggregate(RetTy, Base, NumElts)) {
1057     // The LLVM struct type for such an aggregate should lower properly.
1058     return ABIArgInfo::getDirect();
1059   }
1060 
1061   if (const VectorType *VT = RetTy->getAs<VectorType>()) {
1062     // On Darwin, some vectors are returned in registers.
1063     if (IsDarwinVectorABI) {
1064       uint64_t Size = getContext().getTypeSize(RetTy);
1065 
1066       // 128-bit vectors are a special case; they are returned in
1067       // registers and we need to make sure to pick a type the LLVM
1068       // backend will like.
1069       if (Size == 128)
1070         return ABIArgInfo::getDirect(llvm::VectorType::get(
1071                   llvm::Type::getInt64Ty(getVMContext()), 2));
1072 
1073       // Always return in register if it fits in a general purpose
1074       // register, or if it is 64 bits and has a single element.
1075       if ((Size == 8 || Size == 16 || Size == 32) ||
1076           (Size == 64 && VT->getNumElements() == 1))
1077         return ABIArgInfo::getDirect(llvm::IntegerType::get(getVMContext(),
1078                                                             Size));
1079 
1080       return getIndirectReturnResult(RetTy, State);
1081     }
1082 
1083     return ABIArgInfo::getDirect();
1084   }
1085 
1086   if (isAggregateTypeForABI(RetTy)) {
1087     if (const RecordType *RT = RetTy->getAs<RecordType>()) {
1088       // Structures with flexible arrays are always indirect.
1089       if (RT->getDecl()->hasFlexibleArrayMember())
1090         return getIndirectReturnResult(RetTy, State);
1091     }
1092 
1093     // If specified, structs and unions are always indirect.
1094     if (!IsRetSmallStructInRegABI && !RetTy->isAnyComplexType())
1095       return getIndirectReturnResult(RetTy, State);
1096 
1097     // Small structures which are register sized are generally returned
1098     // in a register.
1099     if (shouldReturnTypeInRegister(RetTy, getContext())) {
1100       uint64_t Size = getContext().getTypeSize(RetTy);
1101 
1102       // As a special-case, if the struct is a "single-element" struct, and
1103       // the field is of type "float" or "double", return it in a
1104       // floating-point register. (MSVC does not apply this special case.)
1105       // We apply a similar transformation for pointer types to improve the
1106       // quality of the generated IR.
1107       if (const Type *SeltTy = isSingleElementStruct(RetTy, getContext()))
1108         if ((!IsWin32StructABI && SeltTy->isRealFloatingType())
1109             || SeltTy->hasPointerRepresentation())
1110           return ABIArgInfo::getDirect(CGT.ConvertType(QualType(SeltTy, 0)));
1111 
1112       // FIXME: We should be able to narrow this integer in cases with dead
1113       // padding.
1114       return ABIArgInfo::getDirect(llvm::IntegerType::get(getVMContext(),Size));
1115     }
1116 
1117     return getIndirectReturnResult(RetTy, State);
1118   }
1119 
1120   // Treat an enum type as its underlying type.
1121   if (const EnumType *EnumTy = RetTy->getAs<EnumType>())
1122     RetTy = EnumTy->getDecl()->getIntegerType();
1123 
1124   return (RetTy->isPromotableIntegerType() ?
1125           ABIArgInfo::getExtend() : ABIArgInfo::getDirect());
1126 }
1127 
1128 static bool isSSEVectorType(ASTContext &Context, QualType Ty) {
1129   return Ty->getAs<VectorType>() && Context.getTypeSize(Ty) == 128;
1130 }
1131 
1132 static bool isRecordWithSSEVectorType(ASTContext &Context, QualType Ty) {
1133   const RecordType *RT = Ty->getAs<RecordType>();
1134   if (!RT)
1135     return 0;
1136   const RecordDecl *RD = RT->getDecl();
1137 
1138   // If this is a C++ record, check the bases first.
1139   if (const CXXRecordDecl *CXXRD = dyn_cast<CXXRecordDecl>(RD))
1140     for (const auto &I : CXXRD->bases())
1141       if (!isRecordWithSSEVectorType(Context, I.getType()))
1142         return false;
1143 
1144   for (const auto *i : RD->fields()) {
1145     QualType FT = i->getType();
1146 
1147     if (isSSEVectorType(Context, FT))
1148       return true;
1149 
1150     if (isRecordWithSSEVectorType(Context, FT))
1151       return true;
1152   }
1153 
1154   return false;
1155 }
1156 
1157 unsigned X86_32ABIInfo::getTypeStackAlignInBytes(QualType Ty,
1158                                                  unsigned Align) const {
1159   // Otherwise, if the alignment is less than or equal to the minimum ABI
1160   // alignment, just use the default; the backend will handle this.
1161   if (Align <= MinABIStackAlignInBytes)
1162     return 0; // Use default alignment.
1163 
1164   // On non-Darwin, the stack type alignment is always 4.
1165   if (!IsDarwinVectorABI) {
1166     // Set explicit alignment, since we may need to realign the top.
1167     return MinABIStackAlignInBytes;
1168   }
1169 
1170   // Otherwise, if the type contains an SSE vector type, the alignment is 16.
1171   if (Align >= 16 && (isSSEVectorType(getContext(), Ty) ||
1172                       isRecordWithSSEVectorType(getContext(), Ty)))
1173     return 16;
1174 
1175   return MinABIStackAlignInBytes;
1176 }
1177 
1178 ABIArgInfo X86_32ABIInfo::getIndirectResult(QualType Ty, bool ByVal,
1179                                             CCState &State) const {
1180   if (!ByVal) {
1181     if (State.FreeRegs) {
1182       --State.FreeRegs; // Non-byval indirects just use one pointer.
1183       return getNaturalAlignIndirectInReg(Ty);
1184     }
1185     return getNaturalAlignIndirect(Ty, false);
1186   }
1187 
1188   // Compute the byval alignment.
1189   unsigned TypeAlign = getContext().getTypeAlign(Ty) / 8;
1190   unsigned StackAlign = getTypeStackAlignInBytes(Ty, TypeAlign);
1191   if (StackAlign == 0)
1192     return ABIArgInfo::getIndirect(CharUnits::fromQuantity(4), /*ByVal=*/true);
1193 
1194   // If the stack alignment is less than the type alignment, realign the
1195   // argument.
1196   bool Realign = TypeAlign > StackAlign;
1197   return ABIArgInfo::getIndirect(CharUnits::fromQuantity(StackAlign),
1198                                  /*ByVal=*/true, Realign);
1199 }
1200 
1201 X86_32ABIInfo::Class X86_32ABIInfo::classify(QualType Ty) const {
1202   const Type *T = isSingleElementStruct(Ty, getContext());
1203   if (!T)
1204     T = Ty.getTypePtr();
1205 
1206   if (const BuiltinType *BT = T->getAs<BuiltinType>()) {
1207     BuiltinType::Kind K = BT->getKind();
1208     if (K == BuiltinType::Float || K == BuiltinType::Double)
1209       return Float;
1210   }
1211   return Integer;
1212 }
1213 
1214 bool X86_32ABIInfo::shouldUseInReg(QualType Ty, CCState &State,
1215                                    bool &NeedsPadding) const {
1216   NeedsPadding = false;
1217   if (!IsSoftFloatABI) {
1218     Class C = classify(Ty);
1219     if (C == Float)
1220       return false;
1221   }
1222 
1223   unsigned Size = getContext().getTypeSize(Ty);
1224   unsigned SizeInRegs = (Size + 31) / 32;
1225 
1226   if (SizeInRegs == 0)
1227     return false;
1228 
1229   if (SizeInRegs > State.FreeRegs) {
1230     State.FreeRegs = 0;
1231     return false;
1232   }
1233 
1234   State.FreeRegs -= SizeInRegs;
1235 
1236   if (State.CC == llvm::CallingConv::X86_FastCall ||
1237       State.CC == llvm::CallingConv::X86_VectorCall) {
1238     if (Size > 32)
1239       return false;
1240 
1241     if (Ty->isIntegralOrEnumerationType())
1242       return true;
1243 
1244     if (Ty->isPointerType())
1245       return true;
1246 
1247     if (Ty->isReferenceType())
1248       return true;
1249 
1250     if (State.FreeRegs)
1251       NeedsPadding = true;
1252 
1253     return false;
1254   }
1255 
1256   return true;
1257 }
1258 
1259 ABIArgInfo X86_32ABIInfo::classifyArgumentType(QualType Ty,
1260                                                CCState &State) const {
1261   // FIXME: Set alignment on indirect arguments.
1262 
1263   Ty = useFirstFieldIfTransparentUnion(Ty);
1264 
1265   // Check with the C++ ABI first.
1266   const RecordType *RT = Ty->getAs<RecordType>();
1267   if (RT) {
1268     CGCXXABI::RecordArgABI RAA = getRecordArgABI(RT, getCXXABI());
1269     if (RAA == CGCXXABI::RAA_Indirect) {
1270       return getIndirectResult(Ty, false, State);
1271     } else if (RAA == CGCXXABI::RAA_DirectInMemory) {
1272       // The field index doesn't matter, we'll fix it up later.
1273       return ABIArgInfo::getInAlloca(/*FieldIndex=*/0);
1274     }
1275   }
1276 
1277   // vectorcall adds the concept of a homogenous vector aggregate, similar
1278   // to other targets.
1279   const Type *Base = nullptr;
1280   uint64_t NumElts = 0;
1281   if (State.CC == llvm::CallingConv::X86_VectorCall &&
1282       isHomogeneousAggregate(Ty, Base, NumElts)) {
1283     if (State.FreeSSERegs >= NumElts) {
1284       State.FreeSSERegs -= NumElts;
1285       if (Ty->isBuiltinType() || Ty->isVectorType())
1286         return ABIArgInfo::getDirect();
1287       return ABIArgInfo::getExpand();
1288     }
1289     return getIndirectResult(Ty, /*ByVal=*/false, State);
1290   }
1291 
1292   if (isAggregateTypeForABI(Ty)) {
1293     if (RT) {
1294       // Structs are always byval on win32, regardless of what they contain.
1295       if (IsWin32StructABI)
1296         return getIndirectResult(Ty, true, State);
1297 
1298       // Structures with flexible arrays are always indirect.
1299       if (RT->getDecl()->hasFlexibleArrayMember())
1300         return getIndirectResult(Ty, true, State);
1301     }
1302 
1303     // Ignore empty structs/unions.
1304     if (isEmptyRecord(getContext(), Ty, true))
1305       return ABIArgInfo::getIgnore();
1306 
1307     llvm::LLVMContext &LLVMContext = getVMContext();
1308     llvm::IntegerType *Int32 = llvm::Type::getInt32Ty(LLVMContext);
1309     bool NeedsPadding;
1310     if (shouldUseInReg(Ty, State, NeedsPadding)) {
1311       unsigned SizeInRegs = (getContext().getTypeSize(Ty) + 31) / 32;
1312       SmallVector<llvm::Type*, 3> Elements(SizeInRegs, Int32);
1313       llvm::Type *Result = llvm::StructType::get(LLVMContext, Elements);
1314       return ABIArgInfo::getDirectInReg(Result);
1315     }
1316     llvm::IntegerType *PaddingType = NeedsPadding ? Int32 : nullptr;
1317 
1318     // Expand small (<= 128-bit) record types when we know that the stack layout
1319     // of those arguments will match the struct. This is important because the
1320     // LLVM backend isn't smart enough to remove byval, which inhibits many
1321     // optimizations.
1322     if (getContext().getTypeSize(Ty) <= 4*32 &&
1323         canExpandIndirectArgument(Ty, getContext()))
1324       return ABIArgInfo::getExpandWithPadding(
1325           State.CC == llvm::CallingConv::X86_FastCall ||
1326               State.CC == llvm::CallingConv::X86_VectorCall,
1327           PaddingType);
1328 
1329     return getIndirectResult(Ty, true, State);
1330   }
1331 
1332   if (const VectorType *VT = Ty->getAs<VectorType>()) {
1333     // On Darwin, some vectors are passed in memory, we handle this by passing
1334     // it as an i8/i16/i32/i64.
1335     if (IsDarwinVectorABI) {
1336       uint64_t Size = getContext().getTypeSize(Ty);
1337       if ((Size == 8 || Size == 16 || Size == 32) ||
1338           (Size == 64 && VT->getNumElements() == 1))
1339         return ABIArgInfo::getDirect(llvm::IntegerType::get(getVMContext(),
1340                                                             Size));
1341     }
1342 
1343     if (IsX86_MMXType(CGT.ConvertType(Ty)))
1344       return ABIArgInfo::getDirect(llvm::IntegerType::get(getVMContext(), 64));
1345 
1346     return ABIArgInfo::getDirect();
1347   }
1348 
1349 
1350   if (const EnumType *EnumTy = Ty->getAs<EnumType>())
1351     Ty = EnumTy->getDecl()->getIntegerType();
1352 
1353   bool NeedsPadding;
1354   bool InReg = shouldUseInReg(Ty, State, NeedsPadding);
1355 
1356   if (Ty->isPromotableIntegerType()) {
1357     if (InReg)
1358       return ABIArgInfo::getExtendInReg();
1359     return ABIArgInfo::getExtend();
1360   }
1361   if (InReg)
1362     return ABIArgInfo::getDirectInReg();
1363   return ABIArgInfo::getDirect();
1364 }
1365 
1366 void X86_32ABIInfo::computeInfo(CGFunctionInfo &FI) const {
1367   CCState State(FI.getCallingConvention());
1368   if (State.CC == llvm::CallingConv::X86_FastCall)
1369     State.FreeRegs = 2;
1370   else if (State.CC == llvm::CallingConv::X86_VectorCall) {
1371     State.FreeRegs = 2;
1372     State.FreeSSERegs = 6;
1373   } else if (FI.getHasRegParm())
1374     State.FreeRegs = FI.getRegParm();
1375   else
1376     State.FreeRegs = DefaultNumRegisterParameters;
1377 
1378   if (!getCXXABI().classifyReturnType(FI)) {
1379     FI.getReturnInfo() = classifyReturnType(FI.getReturnType(), State);
1380   } else if (FI.getReturnInfo().isIndirect()) {
1381     // The C++ ABI is not aware of register usage, so we have to check if the
1382     // return value was sret and put it in a register ourselves if appropriate.
1383     if (State.FreeRegs) {
1384       --State.FreeRegs;  // The sret parameter consumes a register.
1385       FI.getReturnInfo().setInReg(true);
1386     }
1387   }
1388 
1389   // The chain argument effectively gives us another free register.
1390   if (FI.isChainCall())
1391     ++State.FreeRegs;
1392 
1393   bool UsedInAlloca = false;
1394   for (auto &I : FI.arguments()) {
1395     I.info = classifyArgumentType(I.type, State);
1396     UsedInAlloca |= (I.info.getKind() == ABIArgInfo::InAlloca);
1397   }
1398 
1399   // If we needed to use inalloca for any argument, do a second pass and rewrite
1400   // all the memory arguments to use inalloca.
1401   if (UsedInAlloca)
1402     rewriteWithInAlloca(FI);
1403 }
1404 
1405 void
1406 X86_32ABIInfo::addFieldToArgStruct(SmallVector<llvm::Type *, 6> &FrameFields,
1407                                    CharUnits &StackOffset, ABIArgInfo &Info,
1408                                    QualType Type) const {
1409   // Arguments are always 4-byte-aligned.
1410   CharUnits FieldAlign = CharUnits::fromQuantity(4);
1411 
1412   assert(StackOffset.isMultipleOf(FieldAlign) && "unaligned inalloca struct");
1413   Info = ABIArgInfo::getInAlloca(FrameFields.size());
1414   FrameFields.push_back(CGT.ConvertTypeForMem(Type));
1415   StackOffset += getContext().getTypeSizeInChars(Type);
1416 
1417   // Insert padding bytes to respect alignment.
1418   CharUnits FieldEnd = StackOffset;
1419   StackOffset = FieldEnd.RoundUpToAlignment(FieldAlign);
1420   if (StackOffset != FieldEnd) {
1421     CharUnits NumBytes = StackOffset - FieldEnd;
1422     llvm::Type *Ty = llvm::Type::getInt8Ty(getVMContext());
1423     Ty = llvm::ArrayType::get(Ty, NumBytes.getQuantity());
1424     FrameFields.push_back(Ty);
1425   }
1426 }
1427 
1428 static bool isArgInAlloca(const ABIArgInfo &Info) {
1429   // Leave ignored and inreg arguments alone.
1430   switch (Info.getKind()) {
1431   case ABIArgInfo::InAlloca:
1432     return true;
1433   case ABIArgInfo::Indirect:
1434     assert(Info.getIndirectByVal());
1435     return true;
1436   case ABIArgInfo::Ignore:
1437     return false;
1438   case ABIArgInfo::Direct:
1439   case ABIArgInfo::Extend:
1440   case ABIArgInfo::Expand:
1441     if (Info.getInReg())
1442       return false;
1443     return true;
1444   }
1445   llvm_unreachable("invalid enum");
1446 }
1447 
1448 void X86_32ABIInfo::rewriteWithInAlloca(CGFunctionInfo &FI) const {
1449   assert(IsWin32StructABI && "inalloca only supported on win32");
1450 
1451   // Build a packed struct type for all of the arguments in memory.
1452   SmallVector<llvm::Type *, 6> FrameFields;
1453 
1454   // The stack alignment is always 4.
1455   CharUnits StackAlign = CharUnits::fromQuantity(4);
1456 
1457   CharUnits StackOffset;
1458   CGFunctionInfo::arg_iterator I = FI.arg_begin(), E = FI.arg_end();
1459 
1460   // Put 'this' into the struct before 'sret', if necessary.
1461   bool IsThisCall =
1462       FI.getCallingConvention() == llvm::CallingConv::X86_ThisCall;
1463   ABIArgInfo &Ret = FI.getReturnInfo();
1464   if (Ret.isIndirect() && Ret.isSRetAfterThis() && !IsThisCall &&
1465       isArgInAlloca(I->info)) {
1466     addFieldToArgStruct(FrameFields, StackOffset, I->info, I->type);
1467     ++I;
1468   }
1469 
1470   // Put the sret parameter into the inalloca struct if it's in memory.
1471   if (Ret.isIndirect() && !Ret.getInReg()) {
1472     CanQualType PtrTy = getContext().getPointerType(FI.getReturnType());
1473     addFieldToArgStruct(FrameFields, StackOffset, Ret, PtrTy);
1474     // On Windows, the hidden sret parameter is always returned in eax.
1475     Ret.setInAllocaSRet(IsWin32StructABI);
1476   }
1477 
1478   // Skip the 'this' parameter in ecx.
1479   if (IsThisCall)
1480     ++I;
1481 
1482   // Put arguments passed in memory into the struct.
1483   for (; I != E; ++I) {
1484     if (isArgInAlloca(I->info))
1485       addFieldToArgStruct(FrameFields, StackOffset, I->info, I->type);
1486   }
1487 
1488   FI.setArgStruct(llvm::StructType::get(getVMContext(), FrameFields,
1489                                         /*isPacked=*/true),
1490                   StackAlign);
1491 }
1492 
1493 Address X86_32ABIInfo::EmitVAArg(CodeGenFunction &CGF,
1494                                  Address VAListAddr, QualType Ty) const {
1495 
1496   auto TypeInfo = getContext().getTypeInfoInChars(Ty);
1497 
1498   // x86-32 changes the alignment of certain arguments on the stack.
1499   //
1500   // Just messing with TypeInfo like this works because we never pass
1501   // anything indirectly.
1502   TypeInfo.second = CharUnits::fromQuantity(
1503                 getTypeStackAlignInBytes(Ty, TypeInfo.second.getQuantity()));
1504 
1505   return emitVoidPtrVAArg(CGF, VAListAddr, Ty, /*Indirect*/ false,
1506                           TypeInfo, CharUnits::fromQuantity(4),
1507                           /*AllowHigherAlign*/ true);
1508 }
1509 
1510 bool X86_32TargetCodeGenInfo::isStructReturnInRegABI(
1511     const llvm::Triple &Triple, const CodeGenOptions &Opts) {
1512   assert(Triple.getArch() == llvm::Triple::x86);
1513 
1514   switch (Opts.getStructReturnConvention()) {
1515   case CodeGenOptions::SRCK_Default:
1516     break;
1517   case CodeGenOptions::SRCK_OnStack:  // -fpcc-struct-return
1518     return false;
1519   case CodeGenOptions::SRCK_InRegs:  // -freg-struct-return
1520     return true;
1521   }
1522 
1523   if (Triple.isOSDarwin())
1524     return true;
1525 
1526   switch (Triple.getOS()) {
1527   case llvm::Triple::DragonFly:
1528   case llvm::Triple::FreeBSD:
1529   case llvm::Triple::OpenBSD:
1530   case llvm::Triple::Bitrig:
1531   case llvm::Triple::Win32:
1532     return true;
1533   default:
1534     return false;
1535   }
1536 }
1537 
1538 void X86_32TargetCodeGenInfo::setTargetAttributes(const Decl *D,
1539                                                   llvm::GlobalValue *GV,
1540                                             CodeGen::CodeGenModule &CGM) const {
1541   if (const FunctionDecl *FD = dyn_cast_or_null<FunctionDecl>(D)) {
1542     if (FD->hasAttr<X86ForceAlignArgPointerAttr>()) {
1543       // Get the LLVM function.
1544       llvm::Function *Fn = cast<llvm::Function>(GV);
1545 
1546       // Now add the 'alignstack' attribute with a value of 16.
1547       llvm::AttrBuilder B;
1548       B.addStackAlignmentAttr(16);
1549       Fn->addAttributes(llvm::AttributeSet::FunctionIndex,
1550                       llvm::AttributeSet::get(CGM.getLLVMContext(),
1551                                               llvm::AttributeSet::FunctionIndex,
1552                                               B));
1553     }
1554   }
1555 }
1556 
1557 bool X86_32TargetCodeGenInfo::initDwarfEHRegSizeTable(
1558                                                CodeGen::CodeGenFunction &CGF,
1559                                                llvm::Value *Address) const {
1560   CodeGen::CGBuilderTy &Builder = CGF.Builder;
1561 
1562   llvm::Value *Four8 = llvm::ConstantInt::get(CGF.Int8Ty, 4);
1563 
1564   // 0-7 are the eight integer registers;  the order is different
1565   //   on Darwin (for EH), but the range is the same.
1566   // 8 is %eip.
1567   AssignToArrayRange(Builder, Address, Four8, 0, 8);
1568 
1569   if (CGF.CGM.getTarget().getTriple().isOSDarwin()) {
1570     // 12-16 are st(0..4).  Not sure why we stop at 4.
1571     // These have size 16, which is sizeof(long double) on
1572     // platforms with 8-byte alignment for that type.
1573     llvm::Value *Sixteen8 = llvm::ConstantInt::get(CGF.Int8Ty, 16);
1574     AssignToArrayRange(Builder, Address, Sixteen8, 12, 16);
1575 
1576   } else {
1577     // 9 is %eflags, which doesn't get a size on Darwin for some
1578     // reason.
1579     Builder.CreateAlignedStore(
1580         Four8, Builder.CreateConstInBoundsGEP1_32(CGF.Int8Ty, Address, 9),
1581                                CharUnits::One());
1582 
1583     // 11-16 are st(0..5).  Not sure why we stop at 5.
1584     // These have size 12, which is sizeof(long double) on
1585     // platforms with 4-byte alignment for that type.
1586     llvm::Value *Twelve8 = llvm::ConstantInt::get(CGF.Int8Ty, 12);
1587     AssignToArrayRange(Builder, Address, Twelve8, 11, 16);
1588   }
1589 
1590   return false;
1591 }
1592 
1593 //===----------------------------------------------------------------------===//
1594 // X86-64 ABI Implementation
1595 //===----------------------------------------------------------------------===//
1596 
1597 
1598 namespace {
1599 /// The AVX ABI level for X86 targets.
1600 enum class X86AVXABILevel {
1601   None,
1602   AVX,
1603   AVX512
1604 };
1605 
1606 /// \p returns the size in bits of the largest (native) vector for \p AVXLevel.
1607 static unsigned getNativeVectorSizeForAVXABI(X86AVXABILevel AVXLevel) {
1608   switch (AVXLevel) {
1609   case X86AVXABILevel::AVX512:
1610     return 512;
1611   case X86AVXABILevel::AVX:
1612     return 256;
1613   case X86AVXABILevel::None:
1614     return 128;
1615   }
1616   llvm_unreachable("Unknown AVXLevel");
1617 }
1618 
1619 /// X86_64ABIInfo - The X86_64 ABI information.
1620 class X86_64ABIInfo : public ABIInfo {
1621   enum Class {
1622     Integer = 0,
1623     SSE,
1624     SSEUp,
1625     X87,
1626     X87Up,
1627     ComplexX87,
1628     NoClass,
1629     Memory
1630   };
1631 
1632   /// merge - Implement the X86_64 ABI merging algorithm.
1633   ///
1634   /// Merge an accumulating classification \arg Accum with a field
1635   /// classification \arg Field.
1636   ///
1637   /// \param Accum - The accumulating classification. This should
1638   /// always be either NoClass or the result of a previous merge
1639   /// call. In addition, this should never be Memory (the caller
1640   /// should just return Memory for the aggregate).
1641   static Class merge(Class Accum, Class Field);
1642 
1643   /// postMerge - Implement the X86_64 ABI post merging algorithm.
1644   ///
1645   /// Post merger cleanup, reduces a malformed Hi and Lo pair to
1646   /// final MEMORY or SSE classes when necessary.
1647   ///
1648   /// \param AggregateSize - The size of the current aggregate in
1649   /// the classification process.
1650   ///
1651   /// \param Lo - The classification for the parts of the type
1652   /// residing in the low word of the containing object.
1653   ///
1654   /// \param Hi - The classification for the parts of the type
1655   /// residing in the higher words of the containing object.
1656   ///
1657   void postMerge(unsigned AggregateSize, Class &Lo, Class &Hi) const;
1658 
1659   /// classify - Determine the x86_64 register classes in which the
1660   /// given type T should be passed.
1661   ///
1662   /// \param Lo - The classification for the parts of the type
1663   /// residing in the low word of the containing object.
1664   ///
1665   /// \param Hi - The classification for the parts of the type
1666   /// residing in the high word of the containing object.
1667   ///
1668   /// \param OffsetBase - The bit offset of this type in the
1669   /// containing object.  Some parameters are classified different
1670   /// depending on whether they straddle an eightbyte boundary.
1671   ///
1672   /// \param isNamedArg - Whether the argument in question is a "named"
1673   /// argument, as used in AMD64-ABI 3.5.7.
1674   ///
1675   /// If a word is unused its result will be NoClass; if a type should
1676   /// be passed in Memory then at least the classification of \arg Lo
1677   /// will be Memory.
1678   ///
1679   /// The \arg Lo class will be NoClass iff the argument is ignored.
1680   ///
1681   /// If the \arg Lo class is ComplexX87, then the \arg Hi class will
1682   /// also be ComplexX87.
1683   void classify(QualType T, uint64_t OffsetBase, Class &Lo, Class &Hi,
1684                 bool isNamedArg) const;
1685 
1686   llvm::Type *GetByteVectorType(QualType Ty) const;
1687   llvm::Type *GetSSETypeAtOffset(llvm::Type *IRType,
1688                                  unsigned IROffset, QualType SourceTy,
1689                                  unsigned SourceOffset) const;
1690   llvm::Type *GetINTEGERTypeAtOffset(llvm::Type *IRType,
1691                                      unsigned IROffset, QualType SourceTy,
1692                                      unsigned SourceOffset) const;
1693 
1694   /// getIndirectResult - Give a source type \arg Ty, return a suitable result
1695   /// such that the argument will be returned in memory.
1696   ABIArgInfo getIndirectReturnResult(QualType Ty) const;
1697 
1698   /// getIndirectResult - Give a source type \arg Ty, return a suitable result
1699   /// such that the argument will be passed in memory.
1700   ///
1701   /// \param freeIntRegs - The number of free integer registers remaining
1702   /// available.
1703   ABIArgInfo getIndirectResult(QualType Ty, unsigned freeIntRegs) const;
1704 
1705   ABIArgInfo classifyReturnType(QualType RetTy) const;
1706 
1707   ABIArgInfo classifyArgumentType(QualType Ty,
1708                                   unsigned freeIntRegs,
1709                                   unsigned &neededInt,
1710                                   unsigned &neededSSE,
1711                                   bool isNamedArg) const;
1712 
1713   bool IsIllegalVectorType(QualType Ty) const;
1714 
1715   /// The 0.98 ABI revision clarified a lot of ambiguities,
1716   /// unfortunately in ways that were not always consistent with
1717   /// certain previous compilers.  In particular, platforms which
1718   /// required strict binary compatibility with older versions of GCC
1719   /// may need to exempt themselves.
1720   bool honorsRevision0_98() const {
1721     return !getTarget().getTriple().isOSDarwin();
1722   }
1723 
1724   X86AVXABILevel AVXLevel;
1725   // Some ABIs (e.g. X32 ABI and Native Client OS) use 32 bit pointers on
1726   // 64-bit hardware.
1727   bool Has64BitPointers;
1728 
1729 public:
1730   X86_64ABIInfo(CodeGen::CodeGenTypes &CGT, X86AVXABILevel AVXLevel) :
1731       ABIInfo(CGT), AVXLevel(AVXLevel),
1732       Has64BitPointers(CGT.getDataLayout().getPointerSize(0) == 8) {
1733   }
1734 
1735   bool isPassedUsingAVXType(QualType type) const {
1736     unsigned neededInt, neededSSE;
1737     // The freeIntRegs argument doesn't matter here.
1738     ABIArgInfo info = classifyArgumentType(type, 0, neededInt, neededSSE,
1739                                            /*isNamedArg*/true);
1740     if (info.isDirect()) {
1741       llvm::Type *ty = info.getCoerceToType();
1742       if (llvm::VectorType *vectorTy = dyn_cast_or_null<llvm::VectorType>(ty))
1743         return (vectorTy->getBitWidth() > 128);
1744     }
1745     return false;
1746   }
1747 
1748   void computeInfo(CGFunctionInfo &FI) const override;
1749 
1750   Address EmitVAArg(CodeGenFunction &CGF, Address VAListAddr,
1751                     QualType Ty) const override;
1752   Address EmitMSVAArg(CodeGenFunction &CGF, Address VAListAddr,
1753                       QualType Ty) const override;
1754 
1755   bool has64BitPointers() const {
1756     return Has64BitPointers;
1757   }
1758 };
1759 
1760 /// WinX86_64ABIInfo - The Windows X86_64 ABI information.
1761 class WinX86_64ABIInfo : public ABIInfo {
1762 
1763   ABIArgInfo classify(QualType Ty, unsigned &FreeSSERegs,
1764                       bool IsReturnType) const;
1765 
1766 public:
1767   WinX86_64ABIInfo(CodeGen::CodeGenTypes &CGT) : ABIInfo(CGT) {}
1768 
1769   void computeInfo(CGFunctionInfo &FI) const override;
1770 
1771   Address EmitVAArg(CodeGenFunction &CGF, Address VAListAddr,
1772                     QualType Ty) const override;
1773 
1774   bool isHomogeneousAggregateBaseType(QualType Ty) const override {
1775     // FIXME: Assumes vectorcall is in use.
1776     return isX86VectorTypeForVectorCall(getContext(), Ty);
1777   }
1778 
1779   bool isHomogeneousAggregateSmallEnough(const Type *Ty,
1780                                          uint64_t NumMembers) const override {
1781     // FIXME: Assumes vectorcall is in use.
1782     return isX86VectorCallAggregateSmallEnough(NumMembers);
1783   }
1784 };
1785 
1786 class X86_64TargetCodeGenInfo : public TargetCodeGenInfo {
1787 public:
1788   X86_64TargetCodeGenInfo(CodeGen::CodeGenTypes &CGT, X86AVXABILevel AVXLevel)
1789       : TargetCodeGenInfo(new X86_64ABIInfo(CGT, AVXLevel)) {}
1790 
1791   const X86_64ABIInfo &getABIInfo() const {
1792     return static_cast<const X86_64ABIInfo&>(TargetCodeGenInfo::getABIInfo());
1793   }
1794 
1795   int getDwarfEHStackPointer(CodeGen::CodeGenModule &CGM) const override {
1796     return 7;
1797   }
1798 
1799   bool initDwarfEHRegSizeTable(CodeGen::CodeGenFunction &CGF,
1800                                llvm::Value *Address) const override {
1801     llvm::Value *Eight8 = llvm::ConstantInt::get(CGF.Int8Ty, 8);
1802 
1803     // 0-15 are the 16 integer registers.
1804     // 16 is %rip.
1805     AssignToArrayRange(CGF.Builder, Address, Eight8, 0, 16);
1806     return false;
1807   }
1808 
1809   llvm::Type* adjustInlineAsmType(CodeGen::CodeGenFunction &CGF,
1810                                   StringRef Constraint,
1811                                   llvm::Type* Ty) const override {
1812     return X86AdjustInlineAsmType(CGF, Constraint, Ty);
1813   }
1814 
1815   bool isNoProtoCallVariadic(const CallArgList &args,
1816                              const FunctionNoProtoType *fnType) const override {
1817     // The default CC on x86-64 sets %al to the number of SSA
1818     // registers used, and GCC sets this when calling an unprototyped
1819     // function, so we override the default behavior.  However, don't do
1820     // that when AVX types are involved: the ABI explicitly states it is
1821     // undefined, and it doesn't work in practice because of how the ABI
1822     // defines varargs anyway.
1823     if (fnType->getCallConv() == CC_C) {
1824       bool HasAVXType = false;
1825       for (CallArgList::const_iterator
1826              it = args.begin(), ie = args.end(); it != ie; ++it) {
1827         if (getABIInfo().isPassedUsingAVXType(it->Ty)) {
1828           HasAVXType = true;
1829           break;
1830         }
1831       }
1832 
1833       if (!HasAVXType)
1834         return true;
1835     }
1836 
1837     return TargetCodeGenInfo::isNoProtoCallVariadic(args, fnType);
1838   }
1839 
1840   llvm::Constant *
1841   getUBSanFunctionSignature(CodeGen::CodeGenModule &CGM) const override {
1842     unsigned Sig;
1843     if (getABIInfo().has64BitPointers())
1844       Sig = (0xeb << 0) |  // jmp rel8
1845             (0x0a << 8) |  //           .+0x0c
1846             ('F' << 16) |
1847             ('T' << 24);
1848     else
1849       Sig = (0xeb << 0) |  // jmp rel8
1850             (0x06 << 8) |  //           .+0x08
1851             ('F' << 16) |
1852             ('T' << 24);
1853     return llvm::ConstantInt::get(CGM.Int32Ty, Sig);
1854   }
1855 };
1856 
1857 class PS4TargetCodeGenInfo : public X86_64TargetCodeGenInfo {
1858 public:
1859   PS4TargetCodeGenInfo(CodeGen::CodeGenTypes &CGT, X86AVXABILevel AVXLevel)
1860     : X86_64TargetCodeGenInfo(CGT, AVXLevel) {}
1861 
1862   void getDependentLibraryOption(llvm::StringRef Lib,
1863                                  llvm::SmallString<24> &Opt) const override {
1864     Opt = "\01";
1865     // If the argument contains a space, enclose it in quotes.
1866     if (Lib.find(" ") != StringRef::npos)
1867       Opt += "\"" + Lib.str() + "\"";
1868     else
1869       Opt += Lib;
1870   }
1871 };
1872 
1873 static std::string qualifyWindowsLibrary(llvm::StringRef Lib) {
1874   // If the argument does not end in .lib, automatically add the suffix.
1875   // If the argument contains a space, enclose it in quotes.
1876   // This matches the behavior of MSVC.
1877   bool Quote = (Lib.find(" ") != StringRef::npos);
1878   std::string ArgStr = Quote ? "\"" : "";
1879   ArgStr += Lib;
1880   if (!Lib.endswith_lower(".lib"))
1881     ArgStr += ".lib";
1882   ArgStr += Quote ? "\"" : "";
1883   return ArgStr;
1884 }
1885 
1886 class WinX86_32TargetCodeGenInfo : public X86_32TargetCodeGenInfo {
1887 public:
1888   WinX86_32TargetCodeGenInfo(CodeGen::CodeGenTypes &CGT,
1889         bool DarwinVectorABI, bool RetSmallStructInRegABI, bool Win32StructABI,
1890         unsigned NumRegisterParameters)
1891     : X86_32TargetCodeGenInfo(CGT, DarwinVectorABI, RetSmallStructInRegABI,
1892         Win32StructABI, NumRegisterParameters, false) {}
1893 
1894   void setTargetAttributes(const Decl *D, llvm::GlobalValue *GV,
1895                            CodeGen::CodeGenModule &CGM) const override;
1896 
1897   void getDependentLibraryOption(llvm::StringRef Lib,
1898                                  llvm::SmallString<24> &Opt) const override {
1899     Opt = "/DEFAULTLIB:";
1900     Opt += qualifyWindowsLibrary(Lib);
1901   }
1902 
1903   void getDetectMismatchOption(llvm::StringRef Name,
1904                                llvm::StringRef Value,
1905                                llvm::SmallString<32> &Opt) const override {
1906     Opt = "/FAILIFMISMATCH:\"" + Name.str() + "=" + Value.str() + "\"";
1907   }
1908 };
1909 
1910 static void addStackProbeSizeTargetAttribute(const Decl *D,
1911                                              llvm::GlobalValue *GV,
1912                                              CodeGen::CodeGenModule &CGM) {
1913   if (D && isa<FunctionDecl>(D)) {
1914     if (CGM.getCodeGenOpts().StackProbeSize != 4096) {
1915       llvm::Function *Fn = cast<llvm::Function>(GV);
1916 
1917       Fn->addFnAttr("stack-probe-size",
1918                     llvm::utostr(CGM.getCodeGenOpts().StackProbeSize));
1919     }
1920   }
1921 }
1922 
1923 void WinX86_32TargetCodeGenInfo::setTargetAttributes(const Decl *D,
1924                                                      llvm::GlobalValue *GV,
1925                                             CodeGen::CodeGenModule &CGM) const {
1926   X86_32TargetCodeGenInfo::setTargetAttributes(D, GV, CGM);
1927 
1928   addStackProbeSizeTargetAttribute(D, GV, CGM);
1929 }
1930 
1931 class WinX86_64TargetCodeGenInfo : public TargetCodeGenInfo {
1932 public:
1933   WinX86_64TargetCodeGenInfo(CodeGen::CodeGenTypes &CGT,
1934                              X86AVXABILevel AVXLevel)
1935       : TargetCodeGenInfo(new WinX86_64ABIInfo(CGT)) {}
1936 
1937   void setTargetAttributes(const Decl *D, llvm::GlobalValue *GV,
1938                            CodeGen::CodeGenModule &CGM) const override;
1939 
1940   int getDwarfEHStackPointer(CodeGen::CodeGenModule &CGM) const override {
1941     return 7;
1942   }
1943 
1944   bool initDwarfEHRegSizeTable(CodeGen::CodeGenFunction &CGF,
1945                                llvm::Value *Address) const override {
1946     llvm::Value *Eight8 = llvm::ConstantInt::get(CGF.Int8Ty, 8);
1947 
1948     // 0-15 are the 16 integer registers.
1949     // 16 is %rip.
1950     AssignToArrayRange(CGF.Builder, Address, Eight8, 0, 16);
1951     return false;
1952   }
1953 
1954   void getDependentLibraryOption(llvm::StringRef Lib,
1955                                  llvm::SmallString<24> &Opt) const override {
1956     Opt = "/DEFAULTLIB:";
1957     Opt += qualifyWindowsLibrary(Lib);
1958   }
1959 
1960   void getDetectMismatchOption(llvm::StringRef Name,
1961                                llvm::StringRef Value,
1962                                llvm::SmallString<32> &Opt) const override {
1963     Opt = "/FAILIFMISMATCH:\"" + Name.str() + "=" + Value.str() + "\"";
1964   }
1965 };
1966 
1967 void WinX86_64TargetCodeGenInfo::setTargetAttributes(const Decl *D,
1968                                                      llvm::GlobalValue *GV,
1969                                             CodeGen::CodeGenModule &CGM) const {
1970   TargetCodeGenInfo::setTargetAttributes(D, GV, CGM);
1971 
1972   addStackProbeSizeTargetAttribute(D, GV, CGM);
1973 }
1974 }
1975 
1976 void X86_64ABIInfo::postMerge(unsigned AggregateSize, Class &Lo,
1977                               Class &Hi) const {
1978   // AMD64-ABI 3.2.3p2: Rule 5. Then a post merger cleanup is done:
1979   //
1980   // (a) If one of the classes is Memory, the whole argument is passed in
1981   //     memory.
1982   //
1983   // (b) If X87UP is not preceded by X87, the whole argument is passed in
1984   //     memory.
1985   //
1986   // (c) If the size of the aggregate exceeds two eightbytes and the first
1987   //     eightbyte isn't SSE or any other eightbyte isn't SSEUP, the whole
1988   //     argument is passed in memory. NOTE: This is necessary to keep the
1989   //     ABI working for processors that don't support the __m256 type.
1990   //
1991   // (d) If SSEUP is not preceded by SSE or SSEUP, it is converted to SSE.
1992   //
1993   // Some of these are enforced by the merging logic.  Others can arise
1994   // only with unions; for example:
1995   //   union { _Complex double; unsigned; }
1996   //
1997   // Note that clauses (b) and (c) were added in 0.98.
1998   //
1999   if (Hi == Memory)
2000     Lo = Memory;
2001   if (Hi == X87Up && Lo != X87 && honorsRevision0_98())
2002     Lo = Memory;
2003   if (AggregateSize > 128 && (Lo != SSE || Hi != SSEUp))
2004     Lo = Memory;
2005   if (Hi == SSEUp && Lo != SSE)
2006     Hi = SSE;
2007 }
2008 
2009 X86_64ABIInfo::Class X86_64ABIInfo::merge(Class Accum, Class Field) {
2010   // AMD64-ABI 3.2.3p2: Rule 4. Each field of an object is
2011   // classified recursively so that always two fields are
2012   // considered. The resulting class is calculated according to
2013   // the classes of the fields in the eightbyte:
2014   //
2015   // (a) If both classes are equal, this is the resulting class.
2016   //
2017   // (b) If one of the classes is NO_CLASS, the resulting class is
2018   // the other class.
2019   //
2020   // (c) If one of the classes is MEMORY, the result is the MEMORY
2021   // class.
2022   //
2023   // (d) If one of the classes is INTEGER, the result is the
2024   // INTEGER.
2025   //
2026   // (e) If one of the classes is X87, X87UP, COMPLEX_X87 class,
2027   // MEMORY is used as class.
2028   //
2029   // (f) Otherwise class SSE is used.
2030 
2031   // Accum should never be memory (we should have returned) or
2032   // ComplexX87 (because this cannot be passed in a structure).
2033   assert((Accum != Memory && Accum != ComplexX87) &&
2034          "Invalid accumulated classification during merge.");
2035   if (Accum == Field || Field == NoClass)
2036     return Accum;
2037   if (Field == Memory)
2038     return Memory;
2039   if (Accum == NoClass)
2040     return Field;
2041   if (Accum == Integer || Field == Integer)
2042     return Integer;
2043   if (Field == X87 || Field == X87Up || Field == ComplexX87 ||
2044       Accum == X87 || Accum == X87Up)
2045     return Memory;
2046   return SSE;
2047 }
2048 
2049 void X86_64ABIInfo::classify(QualType Ty, uint64_t OffsetBase,
2050                              Class &Lo, Class &Hi, bool isNamedArg) const {
2051   // FIXME: This code can be simplified by introducing a simple value class for
2052   // Class pairs with appropriate constructor methods for the various
2053   // situations.
2054 
2055   // FIXME: Some of the split computations are wrong; unaligned vectors
2056   // shouldn't be passed in registers for example, so there is no chance they
2057   // can straddle an eightbyte. Verify & simplify.
2058 
2059   Lo = Hi = NoClass;
2060 
2061   Class &Current = OffsetBase < 64 ? Lo : Hi;
2062   Current = Memory;
2063 
2064   if (const BuiltinType *BT = Ty->getAs<BuiltinType>()) {
2065     BuiltinType::Kind k = BT->getKind();
2066 
2067     if (k == BuiltinType::Void) {
2068       Current = NoClass;
2069     } else if (k == BuiltinType::Int128 || k == BuiltinType::UInt128) {
2070       Lo = Integer;
2071       Hi = Integer;
2072     } else if (k >= BuiltinType::Bool && k <= BuiltinType::LongLong) {
2073       Current = Integer;
2074     } else if (k == BuiltinType::Float || k == BuiltinType::Double) {
2075       Current = SSE;
2076     } else if (k == BuiltinType::LongDouble) {
2077       const llvm::fltSemantics *LDF = &getTarget().getLongDoubleFormat();
2078       if (LDF == &llvm::APFloat::IEEEquad) {
2079         Lo = SSE;
2080         Hi = SSEUp;
2081       } else if (LDF == &llvm::APFloat::x87DoubleExtended) {
2082         Lo = X87;
2083         Hi = X87Up;
2084       } else if (LDF == &llvm::APFloat::IEEEdouble) {
2085         Current = SSE;
2086       } else
2087         llvm_unreachable("unexpected long double representation!");
2088     }
2089     // FIXME: _Decimal32 and _Decimal64 are SSE.
2090     // FIXME: _float128 and _Decimal128 are (SSE, SSEUp).
2091     return;
2092   }
2093 
2094   if (const EnumType *ET = Ty->getAs<EnumType>()) {
2095     // Classify the underlying integer type.
2096     classify(ET->getDecl()->getIntegerType(), OffsetBase, Lo, Hi, isNamedArg);
2097     return;
2098   }
2099 
2100   if (Ty->hasPointerRepresentation()) {
2101     Current = Integer;
2102     return;
2103   }
2104 
2105   if (Ty->isMemberPointerType()) {
2106     if (Ty->isMemberFunctionPointerType()) {
2107       if (Has64BitPointers) {
2108         // If Has64BitPointers, this is an {i64, i64}, so classify both
2109         // Lo and Hi now.
2110         Lo = Hi = Integer;
2111       } else {
2112         // Otherwise, with 32-bit pointers, this is an {i32, i32}. If that
2113         // straddles an eightbyte boundary, Hi should be classified as well.
2114         uint64_t EB_FuncPtr = (OffsetBase) / 64;
2115         uint64_t EB_ThisAdj = (OffsetBase + 64 - 1) / 64;
2116         if (EB_FuncPtr != EB_ThisAdj) {
2117           Lo = Hi = Integer;
2118         } else {
2119           Current = Integer;
2120         }
2121       }
2122     } else {
2123       Current = Integer;
2124     }
2125     return;
2126   }
2127 
2128   if (const VectorType *VT = Ty->getAs<VectorType>()) {
2129     uint64_t Size = getContext().getTypeSize(VT);
2130     if (Size == 1 || Size == 8 || Size == 16 || Size == 32) {
2131       // gcc passes the following as integer:
2132       // 4 bytes - <4 x char>, <2 x short>, <1 x int>, <1 x float>
2133       // 2 bytes - <2 x char>, <1 x short>
2134       // 1 byte  - <1 x char>
2135       Current = Integer;
2136 
2137       // If this type crosses an eightbyte boundary, it should be
2138       // split.
2139       uint64_t EB_Lo = (OffsetBase) / 64;
2140       uint64_t EB_Hi = (OffsetBase + Size - 1) / 64;
2141       if (EB_Lo != EB_Hi)
2142         Hi = Lo;
2143     } else if (Size == 64) {
2144       // gcc passes <1 x double> in memory. :(
2145       if (VT->getElementType()->isSpecificBuiltinType(BuiltinType::Double))
2146         return;
2147 
2148       // gcc passes <1 x long long> as INTEGER.
2149       if (VT->getElementType()->isSpecificBuiltinType(BuiltinType::LongLong) ||
2150           VT->getElementType()->isSpecificBuiltinType(BuiltinType::ULongLong) ||
2151           VT->getElementType()->isSpecificBuiltinType(BuiltinType::Long) ||
2152           VT->getElementType()->isSpecificBuiltinType(BuiltinType::ULong))
2153         Current = Integer;
2154       else
2155         Current = SSE;
2156 
2157       // If this type crosses an eightbyte boundary, it should be
2158       // split.
2159       if (OffsetBase && OffsetBase != 64)
2160         Hi = Lo;
2161     } else if (Size == 128 ||
2162                (isNamedArg && Size <= getNativeVectorSizeForAVXABI(AVXLevel))) {
2163       // Arguments of 256-bits are split into four eightbyte chunks. The
2164       // least significant one belongs to class SSE and all the others to class
2165       // SSEUP. The original Lo and Hi design considers that types can't be
2166       // greater than 128-bits, so a 64-bit split in Hi and Lo makes sense.
2167       // This design isn't correct for 256-bits, but since there're no cases
2168       // where the upper parts would need to be inspected, avoid adding
2169       // complexity and just consider Hi to match the 64-256 part.
2170       //
2171       // Note that per 3.5.7 of AMD64-ABI, 256-bit args are only passed in
2172       // registers if they are "named", i.e. not part of the "..." of a
2173       // variadic function.
2174       //
2175       // Similarly, per 3.2.3. of the AVX512 draft, 512-bits ("named") args are
2176       // split into eight eightbyte chunks, one SSE and seven SSEUP.
2177       Lo = SSE;
2178       Hi = SSEUp;
2179     }
2180     return;
2181   }
2182 
2183   if (const ComplexType *CT = Ty->getAs<ComplexType>()) {
2184     QualType ET = getContext().getCanonicalType(CT->getElementType());
2185 
2186     uint64_t Size = getContext().getTypeSize(Ty);
2187     if (ET->isIntegralOrEnumerationType()) {
2188       if (Size <= 64)
2189         Current = Integer;
2190       else if (Size <= 128)
2191         Lo = Hi = Integer;
2192     } else if (ET == getContext().FloatTy) {
2193       Current = SSE;
2194     } else if (ET == getContext().DoubleTy) {
2195       Lo = Hi = SSE;
2196     } else if (ET == getContext().LongDoubleTy) {
2197       const llvm::fltSemantics *LDF = &getTarget().getLongDoubleFormat();
2198       if (LDF == &llvm::APFloat::IEEEquad)
2199         Current = Memory;
2200       else if (LDF == &llvm::APFloat::x87DoubleExtended)
2201         Current = ComplexX87;
2202       else if (LDF == &llvm::APFloat::IEEEdouble)
2203         Lo = Hi = SSE;
2204       else
2205         llvm_unreachable("unexpected long double representation!");
2206     }
2207 
2208     // If this complex type crosses an eightbyte boundary then it
2209     // should be split.
2210     uint64_t EB_Real = (OffsetBase) / 64;
2211     uint64_t EB_Imag = (OffsetBase + getContext().getTypeSize(ET)) / 64;
2212     if (Hi == NoClass && EB_Real != EB_Imag)
2213       Hi = Lo;
2214 
2215     return;
2216   }
2217 
2218   if (const ConstantArrayType *AT = getContext().getAsConstantArrayType(Ty)) {
2219     // Arrays are treated like structures.
2220 
2221     uint64_t Size = getContext().getTypeSize(Ty);
2222 
2223     // AMD64-ABI 3.2.3p2: Rule 1. If the size of an object is larger
2224     // than four eightbytes, ..., it has class MEMORY.
2225     if (Size > 256)
2226       return;
2227 
2228     // AMD64-ABI 3.2.3p2: Rule 1. If ..., or it contains unaligned
2229     // fields, it has class MEMORY.
2230     //
2231     // Only need to check alignment of array base.
2232     if (OffsetBase % getContext().getTypeAlign(AT->getElementType()))
2233       return;
2234 
2235     // Otherwise implement simplified merge. We could be smarter about
2236     // this, but it isn't worth it and would be harder to verify.
2237     Current = NoClass;
2238     uint64_t EltSize = getContext().getTypeSize(AT->getElementType());
2239     uint64_t ArraySize = AT->getSize().getZExtValue();
2240 
2241     // The only case a 256-bit wide vector could be used is when the array
2242     // contains a single 256-bit element. Since Lo and Hi logic isn't extended
2243     // to work for sizes wider than 128, early check and fallback to memory.
2244     if (Size > 128 && EltSize != 256)
2245       return;
2246 
2247     for (uint64_t i=0, Offset=OffsetBase; i<ArraySize; ++i, Offset += EltSize) {
2248       Class FieldLo, FieldHi;
2249       classify(AT->getElementType(), Offset, FieldLo, FieldHi, isNamedArg);
2250       Lo = merge(Lo, FieldLo);
2251       Hi = merge(Hi, FieldHi);
2252       if (Lo == Memory || Hi == Memory)
2253         break;
2254     }
2255 
2256     postMerge(Size, Lo, Hi);
2257     assert((Hi != SSEUp || Lo == SSE) && "Invalid SSEUp array classification.");
2258     return;
2259   }
2260 
2261   if (const RecordType *RT = Ty->getAs<RecordType>()) {
2262     uint64_t Size = getContext().getTypeSize(Ty);
2263 
2264     // AMD64-ABI 3.2.3p2: Rule 1. If the size of an object is larger
2265     // than four eightbytes, ..., it has class MEMORY.
2266     if (Size > 256)
2267       return;
2268 
2269     // AMD64-ABI 3.2.3p2: Rule 2. If a C++ object has either a non-trivial
2270     // copy constructor or a non-trivial destructor, it is passed by invisible
2271     // reference.
2272     if (getRecordArgABI(RT, getCXXABI()))
2273       return;
2274 
2275     const RecordDecl *RD = RT->getDecl();
2276 
2277     // Assume variable sized types are passed in memory.
2278     if (RD->hasFlexibleArrayMember())
2279       return;
2280 
2281     const ASTRecordLayout &Layout = getContext().getASTRecordLayout(RD);
2282 
2283     // Reset Lo class, this will be recomputed.
2284     Current = NoClass;
2285 
2286     // If this is a C++ record, classify the bases first.
2287     if (const CXXRecordDecl *CXXRD = dyn_cast<CXXRecordDecl>(RD)) {
2288       for (const auto &I : CXXRD->bases()) {
2289         assert(!I.isVirtual() && !I.getType()->isDependentType() &&
2290                "Unexpected base class!");
2291         const CXXRecordDecl *Base =
2292           cast<CXXRecordDecl>(I.getType()->getAs<RecordType>()->getDecl());
2293 
2294         // Classify this field.
2295         //
2296         // AMD64-ABI 3.2.3p2: Rule 3. If the size of the aggregate exceeds a
2297         // single eightbyte, each is classified separately. Each eightbyte gets
2298         // initialized to class NO_CLASS.
2299         Class FieldLo, FieldHi;
2300         uint64_t Offset =
2301           OffsetBase + getContext().toBits(Layout.getBaseClassOffset(Base));
2302         classify(I.getType(), Offset, FieldLo, FieldHi, isNamedArg);
2303         Lo = merge(Lo, FieldLo);
2304         Hi = merge(Hi, FieldHi);
2305         if (Lo == Memory || Hi == Memory) {
2306           postMerge(Size, Lo, Hi);
2307           return;
2308         }
2309       }
2310     }
2311 
2312     // Classify the fields one at a time, merging the results.
2313     unsigned idx = 0;
2314     for (RecordDecl::field_iterator i = RD->field_begin(), e = RD->field_end();
2315            i != e; ++i, ++idx) {
2316       uint64_t Offset = OffsetBase + Layout.getFieldOffset(idx);
2317       bool BitField = i->isBitField();
2318 
2319       // AMD64-ABI 3.2.3p2: Rule 1. If the size of an object is larger than
2320       // four eightbytes, or it contains unaligned fields, it has class MEMORY.
2321       //
2322       // The only case a 256-bit wide vector could be used is when the struct
2323       // contains a single 256-bit element. Since Lo and Hi logic isn't extended
2324       // to work for sizes wider than 128, early check and fallback to memory.
2325       //
2326       if (Size > 128 && getContext().getTypeSize(i->getType()) != 256) {
2327         Lo = Memory;
2328         postMerge(Size, Lo, Hi);
2329         return;
2330       }
2331       // Note, skip this test for bit-fields, see below.
2332       if (!BitField && Offset % getContext().getTypeAlign(i->getType())) {
2333         Lo = Memory;
2334         postMerge(Size, Lo, Hi);
2335         return;
2336       }
2337 
2338       // Classify this field.
2339       //
2340       // AMD64-ABI 3.2.3p2: Rule 3. If the size of the aggregate
2341       // exceeds a single eightbyte, each is classified
2342       // separately. Each eightbyte gets initialized to class
2343       // NO_CLASS.
2344       Class FieldLo, FieldHi;
2345 
2346       // Bit-fields require special handling, they do not force the
2347       // structure to be passed in memory even if unaligned, and
2348       // therefore they can straddle an eightbyte.
2349       if (BitField) {
2350         // Ignore padding bit-fields.
2351         if (i->isUnnamedBitfield())
2352           continue;
2353 
2354         uint64_t Offset = OffsetBase + Layout.getFieldOffset(idx);
2355         uint64_t Size = i->getBitWidthValue(getContext());
2356 
2357         uint64_t EB_Lo = Offset / 64;
2358         uint64_t EB_Hi = (Offset + Size - 1) / 64;
2359 
2360         if (EB_Lo) {
2361           assert(EB_Hi == EB_Lo && "Invalid classification, type > 16 bytes.");
2362           FieldLo = NoClass;
2363           FieldHi = Integer;
2364         } else {
2365           FieldLo = Integer;
2366           FieldHi = EB_Hi ? Integer : NoClass;
2367         }
2368       } else
2369         classify(i->getType(), Offset, FieldLo, FieldHi, isNamedArg);
2370       Lo = merge(Lo, FieldLo);
2371       Hi = merge(Hi, FieldHi);
2372       if (Lo == Memory || Hi == Memory)
2373         break;
2374     }
2375 
2376     postMerge(Size, Lo, Hi);
2377   }
2378 }
2379 
2380 ABIArgInfo X86_64ABIInfo::getIndirectReturnResult(QualType Ty) const {
2381   // If this is a scalar LLVM value then assume LLVM will pass it in the right
2382   // place naturally.
2383   if (!isAggregateTypeForABI(Ty)) {
2384     // Treat an enum type as its underlying type.
2385     if (const EnumType *EnumTy = Ty->getAs<EnumType>())
2386       Ty = EnumTy->getDecl()->getIntegerType();
2387 
2388     return (Ty->isPromotableIntegerType() ?
2389             ABIArgInfo::getExtend() : ABIArgInfo::getDirect());
2390   }
2391 
2392   return getNaturalAlignIndirect(Ty);
2393 }
2394 
2395 bool X86_64ABIInfo::IsIllegalVectorType(QualType Ty) const {
2396   if (const VectorType *VecTy = Ty->getAs<VectorType>()) {
2397     uint64_t Size = getContext().getTypeSize(VecTy);
2398     unsigned LargestVector = getNativeVectorSizeForAVXABI(AVXLevel);
2399     if (Size <= 64 || Size > LargestVector)
2400       return true;
2401   }
2402 
2403   return false;
2404 }
2405 
2406 ABIArgInfo X86_64ABIInfo::getIndirectResult(QualType Ty,
2407                                             unsigned freeIntRegs) const {
2408   // If this is a scalar LLVM value then assume LLVM will pass it in the right
2409   // place naturally.
2410   //
2411   // This assumption is optimistic, as there could be free registers available
2412   // when we need to pass this argument in memory, and LLVM could try to pass
2413   // the argument in the free register. This does not seem to happen currently,
2414   // but this code would be much safer if we could mark the argument with
2415   // 'onstack'. See PR12193.
2416   if (!isAggregateTypeForABI(Ty) && !IsIllegalVectorType(Ty)) {
2417     // Treat an enum type as its underlying type.
2418     if (const EnumType *EnumTy = Ty->getAs<EnumType>())
2419       Ty = EnumTy->getDecl()->getIntegerType();
2420 
2421     return (Ty->isPromotableIntegerType() ?
2422             ABIArgInfo::getExtend() : ABIArgInfo::getDirect());
2423   }
2424 
2425   if (CGCXXABI::RecordArgABI RAA = getRecordArgABI(Ty, getCXXABI()))
2426     return getNaturalAlignIndirect(Ty, RAA == CGCXXABI::RAA_DirectInMemory);
2427 
2428   // Compute the byval alignment. We specify the alignment of the byval in all
2429   // cases so that the mid-level optimizer knows the alignment of the byval.
2430   unsigned Align = std::max(getContext().getTypeAlign(Ty) / 8, 8U);
2431 
2432   // Attempt to avoid passing indirect results using byval when possible. This
2433   // is important for good codegen.
2434   //
2435   // We do this by coercing the value into a scalar type which the backend can
2436   // handle naturally (i.e., without using byval).
2437   //
2438   // For simplicity, we currently only do this when we have exhausted all of the
2439   // free integer registers. Doing this when there are free integer registers
2440   // would require more care, as we would have to ensure that the coerced value
2441   // did not claim the unused register. That would require either reording the
2442   // arguments to the function (so that any subsequent inreg values came first),
2443   // or only doing this optimization when there were no following arguments that
2444   // might be inreg.
2445   //
2446   // We currently expect it to be rare (particularly in well written code) for
2447   // arguments to be passed on the stack when there are still free integer
2448   // registers available (this would typically imply large structs being passed
2449   // by value), so this seems like a fair tradeoff for now.
2450   //
2451   // We can revisit this if the backend grows support for 'onstack' parameter
2452   // attributes. See PR12193.
2453   if (freeIntRegs == 0) {
2454     uint64_t Size = getContext().getTypeSize(Ty);
2455 
2456     // If this type fits in an eightbyte, coerce it into the matching integral
2457     // type, which will end up on the stack (with alignment 8).
2458     if (Align == 8 && Size <= 64)
2459       return ABIArgInfo::getDirect(llvm::IntegerType::get(getVMContext(),
2460                                                           Size));
2461   }
2462 
2463   return ABIArgInfo::getIndirect(CharUnits::fromQuantity(Align));
2464 }
2465 
2466 /// The ABI specifies that a value should be passed in a full vector XMM/YMM
2467 /// register. Pick an LLVM IR type that will be passed as a vector register.
2468 llvm::Type *X86_64ABIInfo::GetByteVectorType(QualType Ty) const {
2469   // Wrapper structs/arrays that only contain vectors are passed just like
2470   // vectors; strip them off if present.
2471   if (const Type *InnerTy = isSingleElementStruct(Ty, getContext()))
2472     Ty = QualType(InnerTy, 0);
2473 
2474   llvm::Type *IRType = CGT.ConvertType(Ty);
2475   if (isa<llvm::VectorType>(IRType) ||
2476       IRType->getTypeID() == llvm::Type::FP128TyID)
2477     return IRType;
2478 
2479   // We couldn't find the preferred IR vector type for 'Ty'.
2480   uint64_t Size = getContext().getTypeSize(Ty);
2481   assert((Size == 128 || Size == 256) && "Invalid type found!");
2482 
2483   // Return a LLVM IR vector type based on the size of 'Ty'.
2484   return llvm::VectorType::get(llvm::Type::getDoubleTy(getVMContext()),
2485                                Size / 64);
2486 }
2487 
2488 /// BitsContainNoUserData - Return true if the specified [start,end) bit range
2489 /// is known to either be off the end of the specified type or being in
2490 /// alignment padding.  The user type specified is known to be at most 128 bits
2491 /// in size, and have passed through X86_64ABIInfo::classify with a successful
2492 /// classification that put one of the two halves in the INTEGER class.
2493 ///
2494 /// It is conservatively correct to return false.
2495 static bool BitsContainNoUserData(QualType Ty, unsigned StartBit,
2496                                   unsigned EndBit, ASTContext &Context) {
2497   // If the bytes being queried are off the end of the type, there is no user
2498   // data hiding here.  This handles analysis of builtins, vectors and other
2499   // types that don't contain interesting padding.
2500   unsigned TySize = (unsigned)Context.getTypeSize(Ty);
2501   if (TySize <= StartBit)
2502     return true;
2503 
2504   if (const ConstantArrayType *AT = Context.getAsConstantArrayType(Ty)) {
2505     unsigned EltSize = (unsigned)Context.getTypeSize(AT->getElementType());
2506     unsigned NumElts = (unsigned)AT->getSize().getZExtValue();
2507 
2508     // Check each element to see if the element overlaps with the queried range.
2509     for (unsigned i = 0; i != NumElts; ++i) {
2510       // If the element is after the span we care about, then we're done..
2511       unsigned EltOffset = i*EltSize;
2512       if (EltOffset >= EndBit) break;
2513 
2514       unsigned EltStart = EltOffset < StartBit ? StartBit-EltOffset :0;
2515       if (!BitsContainNoUserData(AT->getElementType(), EltStart,
2516                                  EndBit-EltOffset, Context))
2517         return false;
2518     }
2519     // If it overlaps no elements, then it is safe to process as padding.
2520     return true;
2521   }
2522 
2523   if (const RecordType *RT = Ty->getAs<RecordType>()) {
2524     const RecordDecl *RD = RT->getDecl();
2525     const ASTRecordLayout &Layout = Context.getASTRecordLayout(RD);
2526 
2527     // If this is a C++ record, check the bases first.
2528     if (const CXXRecordDecl *CXXRD = dyn_cast<CXXRecordDecl>(RD)) {
2529       for (const auto &I : CXXRD->bases()) {
2530         assert(!I.isVirtual() && !I.getType()->isDependentType() &&
2531                "Unexpected base class!");
2532         const CXXRecordDecl *Base =
2533           cast<CXXRecordDecl>(I.getType()->getAs<RecordType>()->getDecl());
2534 
2535         // If the base is after the span we care about, ignore it.
2536         unsigned BaseOffset = Context.toBits(Layout.getBaseClassOffset(Base));
2537         if (BaseOffset >= EndBit) continue;
2538 
2539         unsigned BaseStart = BaseOffset < StartBit ? StartBit-BaseOffset :0;
2540         if (!BitsContainNoUserData(I.getType(), BaseStart,
2541                                    EndBit-BaseOffset, Context))
2542           return false;
2543       }
2544     }
2545 
2546     // Verify that no field has data that overlaps the region of interest.  Yes
2547     // this could be sped up a lot by being smarter about queried fields,
2548     // however we're only looking at structs up to 16 bytes, so we don't care
2549     // much.
2550     unsigned idx = 0;
2551     for (RecordDecl::field_iterator i = RD->field_begin(), e = RD->field_end();
2552          i != e; ++i, ++idx) {
2553       unsigned FieldOffset = (unsigned)Layout.getFieldOffset(idx);
2554 
2555       // If we found a field after the region we care about, then we're done.
2556       if (FieldOffset >= EndBit) break;
2557 
2558       unsigned FieldStart = FieldOffset < StartBit ? StartBit-FieldOffset :0;
2559       if (!BitsContainNoUserData(i->getType(), FieldStart, EndBit-FieldOffset,
2560                                  Context))
2561         return false;
2562     }
2563 
2564     // If nothing in this record overlapped the area of interest, then we're
2565     // clean.
2566     return true;
2567   }
2568 
2569   return false;
2570 }
2571 
2572 /// ContainsFloatAtOffset - Return true if the specified LLVM IR type has a
2573 /// float member at the specified offset.  For example, {int,{float}} has a
2574 /// float at offset 4.  It is conservatively correct for this routine to return
2575 /// false.
2576 static bool ContainsFloatAtOffset(llvm::Type *IRType, unsigned IROffset,
2577                                   const llvm::DataLayout &TD) {
2578   // Base case if we find a float.
2579   if (IROffset == 0 && IRType->isFloatTy())
2580     return true;
2581 
2582   // If this is a struct, recurse into the field at the specified offset.
2583   if (llvm::StructType *STy = dyn_cast<llvm::StructType>(IRType)) {
2584     const llvm::StructLayout *SL = TD.getStructLayout(STy);
2585     unsigned Elt = SL->getElementContainingOffset(IROffset);
2586     IROffset -= SL->getElementOffset(Elt);
2587     return ContainsFloatAtOffset(STy->getElementType(Elt), IROffset, TD);
2588   }
2589 
2590   // If this is an array, recurse into the field at the specified offset.
2591   if (llvm::ArrayType *ATy = dyn_cast<llvm::ArrayType>(IRType)) {
2592     llvm::Type *EltTy = ATy->getElementType();
2593     unsigned EltSize = TD.getTypeAllocSize(EltTy);
2594     IROffset -= IROffset/EltSize*EltSize;
2595     return ContainsFloatAtOffset(EltTy, IROffset, TD);
2596   }
2597 
2598   return false;
2599 }
2600 
2601 
2602 /// GetSSETypeAtOffset - Return a type that will be passed by the backend in the
2603 /// low 8 bytes of an XMM register, corresponding to the SSE class.
2604 llvm::Type *X86_64ABIInfo::
2605 GetSSETypeAtOffset(llvm::Type *IRType, unsigned IROffset,
2606                    QualType SourceTy, unsigned SourceOffset) const {
2607   // The only three choices we have are either double, <2 x float>, or float. We
2608   // pass as float if the last 4 bytes is just padding.  This happens for
2609   // structs that contain 3 floats.
2610   if (BitsContainNoUserData(SourceTy, SourceOffset*8+32,
2611                             SourceOffset*8+64, getContext()))
2612     return llvm::Type::getFloatTy(getVMContext());
2613 
2614   // We want to pass as <2 x float> if the LLVM IR type contains a float at
2615   // offset+0 and offset+4.  Walk the LLVM IR type to find out if this is the
2616   // case.
2617   if (ContainsFloatAtOffset(IRType, IROffset, getDataLayout()) &&
2618       ContainsFloatAtOffset(IRType, IROffset+4, getDataLayout()))
2619     return llvm::VectorType::get(llvm::Type::getFloatTy(getVMContext()), 2);
2620 
2621   return llvm::Type::getDoubleTy(getVMContext());
2622 }
2623 
2624 
2625 /// GetINTEGERTypeAtOffset - The ABI specifies that a value should be passed in
2626 /// an 8-byte GPR.  This means that we either have a scalar or we are talking
2627 /// about the high or low part of an up-to-16-byte struct.  This routine picks
2628 /// the best LLVM IR type to represent this, which may be i64 or may be anything
2629 /// else that the backend will pass in a GPR that works better (e.g. i8, %foo*,
2630 /// etc).
2631 ///
2632 /// PrefType is an LLVM IR type that corresponds to (part of) the IR type for
2633 /// the source type.  IROffset is an offset in bytes into the LLVM IR type that
2634 /// the 8-byte value references.  PrefType may be null.
2635 ///
2636 /// SourceTy is the source-level type for the entire argument.  SourceOffset is
2637 /// an offset into this that we're processing (which is always either 0 or 8).
2638 ///
2639 llvm::Type *X86_64ABIInfo::
2640 GetINTEGERTypeAtOffset(llvm::Type *IRType, unsigned IROffset,
2641                        QualType SourceTy, unsigned SourceOffset) const {
2642   // If we're dealing with an un-offset LLVM IR type, then it means that we're
2643   // returning an 8-byte unit starting with it.  See if we can safely use it.
2644   if (IROffset == 0) {
2645     // Pointers and int64's always fill the 8-byte unit.
2646     if ((isa<llvm::PointerType>(IRType) && Has64BitPointers) ||
2647         IRType->isIntegerTy(64))
2648       return IRType;
2649 
2650     // If we have a 1/2/4-byte integer, we can use it only if the rest of the
2651     // goodness in the source type is just tail padding.  This is allowed to
2652     // kick in for struct {double,int} on the int, but not on
2653     // struct{double,int,int} because we wouldn't return the second int.  We
2654     // have to do this analysis on the source type because we can't depend on
2655     // unions being lowered a specific way etc.
2656     if (IRType->isIntegerTy(8) || IRType->isIntegerTy(16) ||
2657         IRType->isIntegerTy(32) ||
2658         (isa<llvm::PointerType>(IRType) && !Has64BitPointers)) {
2659       unsigned BitWidth = isa<llvm::PointerType>(IRType) ? 32 :
2660           cast<llvm::IntegerType>(IRType)->getBitWidth();
2661 
2662       if (BitsContainNoUserData(SourceTy, SourceOffset*8+BitWidth,
2663                                 SourceOffset*8+64, getContext()))
2664         return IRType;
2665     }
2666   }
2667 
2668   if (llvm::StructType *STy = dyn_cast<llvm::StructType>(IRType)) {
2669     // If this is a struct, recurse into the field at the specified offset.
2670     const llvm::StructLayout *SL = getDataLayout().getStructLayout(STy);
2671     if (IROffset < SL->getSizeInBytes()) {
2672       unsigned FieldIdx = SL->getElementContainingOffset(IROffset);
2673       IROffset -= SL->getElementOffset(FieldIdx);
2674 
2675       return GetINTEGERTypeAtOffset(STy->getElementType(FieldIdx), IROffset,
2676                                     SourceTy, SourceOffset);
2677     }
2678   }
2679 
2680   if (llvm::ArrayType *ATy = dyn_cast<llvm::ArrayType>(IRType)) {
2681     llvm::Type *EltTy = ATy->getElementType();
2682     unsigned EltSize = getDataLayout().getTypeAllocSize(EltTy);
2683     unsigned EltOffset = IROffset/EltSize*EltSize;
2684     return GetINTEGERTypeAtOffset(EltTy, IROffset-EltOffset, SourceTy,
2685                                   SourceOffset);
2686   }
2687 
2688   // Okay, we don't have any better idea of what to pass, so we pass this in an
2689   // integer register that isn't too big to fit the rest of the struct.
2690   unsigned TySizeInBytes =
2691     (unsigned)getContext().getTypeSizeInChars(SourceTy).getQuantity();
2692 
2693   assert(TySizeInBytes != SourceOffset && "Empty field?");
2694 
2695   // It is always safe to classify this as an integer type up to i64 that
2696   // isn't larger than the structure.
2697   return llvm::IntegerType::get(getVMContext(),
2698                                 std::min(TySizeInBytes-SourceOffset, 8U)*8);
2699 }
2700 
2701 
2702 /// GetX86_64ByValArgumentPair - Given a high and low type that can ideally
2703 /// be used as elements of a two register pair to pass or return, return a
2704 /// first class aggregate to represent them.  For example, if the low part of
2705 /// a by-value argument should be passed as i32* and the high part as float,
2706 /// return {i32*, float}.
2707 static llvm::Type *
2708 GetX86_64ByValArgumentPair(llvm::Type *Lo, llvm::Type *Hi,
2709                            const llvm::DataLayout &TD) {
2710   // In order to correctly satisfy the ABI, we need to the high part to start
2711   // at offset 8.  If the high and low parts we inferred are both 4-byte types
2712   // (e.g. i32 and i32) then the resultant struct type ({i32,i32}) won't have
2713   // the second element at offset 8.  Check for this:
2714   unsigned LoSize = (unsigned)TD.getTypeAllocSize(Lo);
2715   unsigned HiAlign = TD.getABITypeAlignment(Hi);
2716   unsigned HiStart = llvm::RoundUpToAlignment(LoSize, HiAlign);
2717   assert(HiStart != 0 && HiStart <= 8 && "Invalid x86-64 argument pair!");
2718 
2719   // To handle this, we have to increase the size of the low part so that the
2720   // second element will start at an 8 byte offset.  We can't increase the size
2721   // of the second element because it might make us access off the end of the
2722   // struct.
2723   if (HiStart != 8) {
2724     // There are usually two sorts of types the ABI generation code can produce
2725     // for the low part of a pair that aren't 8 bytes in size: float or
2726     // i8/i16/i32.  This can also include pointers when they are 32-bit (X32 and
2727     // NaCl).
2728     // Promote these to a larger type.
2729     if (Lo->isFloatTy())
2730       Lo = llvm::Type::getDoubleTy(Lo->getContext());
2731     else {
2732       assert((Lo->isIntegerTy() || Lo->isPointerTy())
2733              && "Invalid/unknown lo type");
2734       Lo = llvm::Type::getInt64Ty(Lo->getContext());
2735     }
2736   }
2737 
2738   llvm::StructType *Result = llvm::StructType::get(Lo, Hi, nullptr);
2739 
2740 
2741   // Verify that the second element is at an 8-byte offset.
2742   assert(TD.getStructLayout(Result)->getElementOffset(1) == 8 &&
2743          "Invalid x86-64 argument pair!");
2744   return Result;
2745 }
2746 
2747 ABIArgInfo X86_64ABIInfo::
2748 classifyReturnType(QualType RetTy) const {
2749   // AMD64-ABI 3.2.3p4: Rule 1. Classify the return type with the
2750   // classification algorithm.
2751   X86_64ABIInfo::Class Lo, Hi;
2752   classify(RetTy, 0, Lo, Hi, /*isNamedArg*/ true);
2753 
2754   // Check some invariants.
2755   assert((Hi != Memory || Lo == Memory) && "Invalid memory classification.");
2756   assert((Hi != SSEUp || Lo == SSE) && "Invalid SSEUp classification.");
2757 
2758   llvm::Type *ResType = nullptr;
2759   switch (Lo) {
2760   case NoClass:
2761     if (Hi == NoClass)
2762       return ABIArgInfo::getIgnore();
2763     // If the low part is just padding, it takes no register, leave ResType
2764     // null.
2765     assert((Hi == SSE || Hi == Integer || Hi == X87Up) &&
2766            "Unknown missing lo part");
2767     break;
2768 
2769   case SSEUp:
2770   case X87Up:
2771     llvm_unreachable("Invalid classification for lo word.");
2772 
2773     // AMD64-ABI 3.2.3p4: Rule 2. Types of class memory are returned via
2774     // hidden argument.
2775   case Memory:
2776     return getIndirectReturnResult(RetTy);
2777 
2778     // AMD64-ABI 3.2.3p4: Rule 3. If the class is INTEGER, the next
2779     // available register of the sequence %rax, %rdx is used.
2780   case Integer:
2781     ResType = GetINTEGERTypeAtOffset(CGT.ConvertType(RetTy), 0, RetTy, 0);
2782 
2783     // If we have a sign or zero extended integer, make sure to return Extend
2784     // so that the parameter gets the right LLVM IR attributes.
2785     if (Hi == NoClass && isa<llvm::IntegerType>(ResType)) {
2786       // Treat an enum type as its underlying type.
2787       if (const EnumType *EnumTy = RetTy->getAs<EnumType>())
2788         RetTy = EnumTy->getDecl()->getIntegerType();
2789 
2790       if (RetTy->isIntegralOrEnumerationType() &&
2791           RetTy->isPromotableIntegerType())
2792         return ABIArgInfo::getExtend();
2793     }
2794     break;
2795 
2796     // AMD64-ABI 3.2.3p4: Rule 4. If the class is SSE, the next
2797     // available SSE register of the sequence %xmm0, %xmm1 is used.
2798   case SSE:
2799     ResType = GetSSETypeAtOffset(CGT.ConvertType(RetTy), 0, RetTy, 0);
2800     break;
2801 
2802     // AMD64-ABI 3.2.3p4: Rule 6. If the class is X87, the value is
2803     // returned on the X87 stack in %st0 as 80-bit x87 number.
2804   case X87:
2805     ResType = llvm::Type::getX86_FP80Ty(getVMContext());
2806     break;
2807 
2808     // AMD64-ABI 3.2.3p4: Rule 8. If the class is COMPLEX_X87, the real
2809     // part of the value is returned in %st0 and the imaginary part in
2810     // %st1.
2811   case ComplexX87:
2812     assert(Hi == ComplexX87 && "Unexpected ComplexX87 classification.");
2813     ResType = llvm::StructType::get(llvm::Type::getX86_FP80Ty(getVMContext()),
2814                                     llvm::Type::getX86_FP80Ty(getVMContext()),
2815                                     nullptr);
2816     break;
2817   }
2818 
2819   llvm::Type *HighPart = nullptr;
2820   switch (Hi) {
2821     // Memory was handled previously and X87 should
2822     // never occur as a hi class.
2823   case Memory:
2824   case X87:
2825     llvm_unreachable("Invalid classification for hi word.");
2826 
2827   case ComplexX87: // Previously handled.
2828   case NoClass:
2829     break;
2830 
2831   case Integer:
2832     HighPart = GetINTEGERTypeAtOffset(CGT.ConvertType(RetTy), 8, RetTy, 8);
2833     if (Lo == NoClass)  // Return HighPart at offset 8 in memory.
2834       return ABIArgInfo::getDirect(HighPart, 8);
2835     break;
2836   case SSE:
2837     HighPart = GetSSETypeAtOffset(CGT.ConvertType(RetTy), 8, RetTy, 8);
2838     if (Lo == NoClass)  // Return HighPart at offset 8 in memory.
2839       return ABIArgInfo::getDirect(HighPart, 8);
2840     break;
2841 
2842     // AMD64-ABI 3.2.3p4: Rule 5. If the class is SSEUP, the eightbyte
2843     // is passed in the next available eightbyte chunk if the last used
2844     // vector register.
2845     //
2846     // SSEUP should always be preceded by SSE, just widen.
2847   case SSEUp:
2848     assert(Lo == SSE && "Unexpected SSEUp classification.");
2849     ResType = GetByteVectorType(RetTy);
2850     break;
2851 
2852     // AMD64-ABI 3.2.3p4: Rule 7. If the class is X87UP, the value is
2853     // returned together with the previous X87 value in %st0.
2854   case X87Up:
2855     // If X87Up is preceded by X87, we don't need to do
2856     // anything. However, in some cases with unions it may not be
2857     // preceded by X87. In such situations we follow gcc and pass the
2858     // extra bits in an SSE reg.
2859     if (Lo != X87) {
2860       HighPart = GetSSETypeAtOffset(CGT.ConvertType(RetTy), 8, RetTy, 8);
2861       if (Lo == NoClass)  // Return HighPart at offset 8 in memory.
2862         return ABIArgInfo::getDirect(HighPart, 8);
2863     }
2864     break;
2865   }
2866 
2867   // If a high part was specified, merge it together with the low part.  It is
2868   // known to pass in the high eightbyte of the result.  We do this by forming a
2869   // first class struct aggregate with the high and low part: {low, high}
2870   if (HighPart)
2871     ResType = GetX86_64ByValArgumentPair(ResType, HighPart, getDataLayout());
2872 
2873   return ABIArgInfo::getDirect(ResType);
2874 }
2875 
2876 ABIArgInfo X86_64ABIInfo::classifyArgumentType(
2877   QualType Ty, unsigned freeIntRegs, unsigned &neededInt, unsigned &neededSSE,
2878   bool isNamedArg)
2879   const
2880 {
2881   Ty = useFirstFieldIfTransparentUnion(Ty);
2882 
2883   X86_64ABIInfo::Class Lo, Hi;
2884   classify(Ty, 0, Lo, Hi, isNamedArg);
2885 
2886   // Check some invariants.
2887   // FIXME: Enforce these by construction.
2888   assert((Hi != Memory || Lo == Memory) && "Invalid memory classification.");
2889   assert((Hi != SSEUp || Lo == SSE) && "Invalid SSEUp classification.");
2890 
2891   neededInt = 0;
2892   neededSSE = 0;
2893   llvm::Type *ResType = nullptr;
2894   switch (Lo) {
2895   case NoClass:
2896     if (Hi == NoClass)
2897       return ABIArgInfo::getIgnore();
2898     // If the low part is just padding, it takes no register, leave ResType
2899     // null.
2900     assert((Hi == SSE || Hi == Integer || Hi == X87Up) &&
2901            "Unknown missing lo part");
2902     break;
2903 
2904     // AMD64-ABI 3.2.3p3: Rule 1. If the class is MEMORY, pass the argument
2905     // on the stack.
2906   case Memory:
2907 
2908     // AMD64-ABI 3.2.3p3: Rule 5. If the class is X87, X87UP or
2909     // COMPLEX_X87, it is passed in memory.
2910   case X87:
2911   case ComplexX87:
2912     if (getRecordArgABI(Ty, getCXXABI()) == CGCXXABI::RAA_Indirect)
2913       ++neededInt;
2914     return getIndirectResult(Ty, freeIntRegs);
2915 
2916   case SSEUp:
2917   case X87Up:
2918     llvm_unreachable("Invalid classification for lo word.");
2919 
2920     // AMD64-ABI 3.2.3p3: Rule 2. If the class is INTEGER, the next
2921     // available register of the sequence %rdi, %rsi, %rdx, %rcx, %r8
2922     // and %r9 is used.
2923   case Integer:
2924     ++neededInt;
2925 
2926     // Pick an 8-byte type based on the preferred type.
2927     ResType = GetINTEGERTypeAtOffset(CGT.ConvertType(Ty), 0, Ty, 0);
2928 
2929     // If we have a sign or zero extended integer, make sure to return Extend
2930     // so that the parameter gets the right LLVM IR attributes.
2931     if (Hi == NoClass && isa<llvm::IntegerType>(ResType)) {
2932       // Treat an enum type as its underlying type.
2933       if (const EnumType *EnumTy = Ty->getAs<EnumType>())
2934         Ty = EnumTy->getDecl()->getIntegerType();
2935 
2936       if (Ty->isIntegralOrEnumerationType() &&
2937           Ty->isPromotableIntegerType())
2938         return ABIArgInfo::getExtend();
2939     }
2940 
2941     break;
2942 
2943     // AMD64-ABI 3.2.3p3: Rule 3. If the class is SSE, the next
2944     // available SSE register is used, the registers are taken in the
2945     // order from %xmm0 to %xmm7.
2946   case SSE: {
2947     llvm::Type *IRType = CGT.ConvertType(Ty);
2948     ResType = GetSSETypeAtOffset(IRType, 0, Ty, 0);
2949     ++neededSSE;
2950     break;
2951   }
2952   }
2953 
2954   llvm::Type *HighPart = nullptr;
2955   switch (Hi) {
2956     // Memory was handled previously, ComplexX87 and X87 should
2957     // never occur as hi classes, and X87Up must be preceded by X87,
2958     // which is passed in memory.
2959   case Memory:
2960   case X87:
2961   case ComplexX87:
2962     llvm_unreachable("Invalid classification for hi word.");
2963 
2964   case NoClass: break;
2965 
2966   case Integer:
2967     ++neededInt;
2968     // Pick an 8-byte type based on the preferred type.
2969     HighPart = GetINTEGERTypeAtOffset(CGT.ConvertType(Ty), 8, Ty, 8);
2970 
2971     if (Lo == NoClass)  // Pass HighPart at offset 8 in memory.
2972       return ABIArgInfo::getDirect(HighPart, 8);
2973     break;
2974 
2975     // X87Up generally doesn't occur here (long double is passed in
2976     // memory), except in situations involving unions.
2977   case X87Up:
2978   case SSE:
2979     HighPart = GetSSETypeAtOffset(CGT.ConvertType(Ty), 8, Ty, 8);
2980 
2981     if (Lo == NoClass)  // Pass HighPart at offset 8 in memory.
2982       return ABIArgInfo::getDirect(HighPart, 8);
2983 
2984     ++neededSSE;
2985     break;
2986 
2987     // AMD64-ABI 3.2.3p3: Rule 4. If the class is SSEUP, the
2988     // eightbyte is passed in the upper half of the last used SSE
2989     // register.  This only happens when 128-bit vectors are passed.
2990   case SSEUp:
2991     assert(Lo == SSE && "Unexpected SSEUp classification");
2992     ResType = GetByteVectorType(Ty);
2993     break;
2994   }
2995 
2996   // If a high part was specified, merge it together with the low part.  It is
2997   // known to pass in the high eightbyte of the result.  We do this by forming a
2998   // first class struct aggregate with the high and low part: {low, high}
2999   if (HighPart)
3000     ResType = GetX86_64ByValArgumentPair(ResType, HighPart, getDataLayout());
3001 
3002   return ABIArgInfo::getDirect(ResType);
3003 }
3004 
3005 void X86_64ABIInfo::computeInfo(CGFunctionInfo &FI) const {
3006 
3007   if (!getCXXABI().classifyReturnType(FI))
3008     FI.getReturnInfo() = classifyReturnType(FI.getReturnType());
3009 
3010   // Keep track of the number of assigned registers.
3011   unsigned freeIntRegs = 6, freeSSERegs = 8;
3012 
3013   // If the return value is indirect, then the hidden argument is consuming one
3014   // integer register.
3015   if (FI.getReturnInfo().isIndirect())
3016     --freeIntRegs;
3017 
3018   // The chain argument effectively gives us another free register.
3019   if (FI.isChainCall())
3020     ++freeIntRegs;
3021 
3022   unsigned NumRequiredArgs = FI.getNumRequiredArgs();
3023   // AMD64-ABI 3.2.3p3: Once arguments are classified, the registers
3024   // get assigned (in left-to-right order) for passing as follows...
3025   unsigned ArgNo = 0;
3026   for (CGFunctionInfo::arg_iterator it = FI.arg_begin(), ie = FI.arg_end();
3027        it != ie; ++it, ++ArgNo) {
3028     bool IsNamedArg = ArgNo < NumRequiredArgs;
3029 
3030     unsigned neededInt, neededSSE;
3031     it->info = classifyArgumentType(it->type, freeIntRegs, neededInt,
3032                                     neededSSE, IsNamedArg);
3033 
3034     // AMD64-ABI 3.2.3p3: If there are no registers available for any
3035     // eightbyte of an argument, the whole argument is passed on the
3036     // stack. If registers have already been assigned for some
3037     // eightbytes of such an argument, the assignments get reverted.
3038     if (freeIntRegs >= neededInt && freeSSERegs >= neededSSE) {
3039       freeIntRegs -= neededInt;
3040       freeSSERegs -= neededSSE;
3041     } else {
3042       it->info = getIndirectResult(it->type, freeIntRegs);
3043     }
3044   }
3045 }
3046 
3047 static Address EmitX86_64VAArgFromMemory(CodeGenFunction &CGF,
3048                                          Address VAListAddr, QualType Ty) {
3049   Address overflow_arg_area_p = CGF.Builder.CreateStructGEP(
3050       VAListAddr, 2, CharUnits::fromQuantity(8), "overflow_arg_area_p");
3051   llvm::Value *overflow_arg_area =
3052     CGF.Builder.CreateLoad(overflow_arg_area_p, "overflow_arg_area");
3053 
3054   // AMD64-ABI 3.5.7p5: Step 7. Align l->overflow_arg_area upwards to a 16
3055   // byte boundary if alignment needed by type exceeds 8 byte boundary.
3056   // It isn't stated explicitly in the standard, but in practice we use
3057   // alignment greater than 16 where necessary.
3058   uint64_t Align = CGF.getContext().getTypeAlignInChars(Ty).getQuantity();
3059   if (Align > 8) {
3060     // overflow_arg_area = (overflow_arg_area + align - 1) & -align;
3061     llvm::Value *Offset =
3062       llvm::ConstantInt::get(CGF.Int64Ty, Align - 1);
3063     overflow_arg_area = CGF.Builder.CreateGEP(overflow_arg_area, Offset);
3064     llvm::Value *AsInt = CGF.Builder.CreatePtrToInt(overflow_arg_area,
3065                                                     CGF.Int64Ty);
3066     llvm::Value *Mask = llvm::ConstantInt::get(CGF.Int64Ty, -(uint64_t)Align);
3067     overflow_arg_area =
3068       CGF.Builder.CreateIntToPtr(CGF.Builder.CreateAnd(AsInt, Mask),
3069                                  overflow_arg_area->getType(),
3070                                  "overflow_arg_area.align");
3071   }
3072 
3073   // AMD64-ABI 3.5.7p5: Step 8. Fetch type from l->overflow_arg_area.
3074   llvm::Type *LTy = CGF.ConvertTypeForMem(Ty);
3075   llvm::Value *Res =
3076     CGF.Builder.CreateBitCast(overflow_arg_area,
3077                               llvm::PointerType::getUnqual(LTy));
3078 
3079   // AMD64-ABI 3.5.7p5: Step 9. Set l->overflow_arg_area to:
3080   // l->overflow_arg_area + sizeof(type).
3081   // AMD64-ABI 3.5.7p5: Step 10. Align l->overflow_arg_area upwards to
3082   // an 8 byte boundary.
3083 
3084   uint64_t SizeInBytes = (CGF.getContext().getTypeSize(Ty) + 7) / 8;
3085   llvm::Value *Offset =
3086       llvm::ConstantInt::get(CGF.Int32Ty, (SizeInBytes + 7)  & ~7);
3087   overflow_arg_area = CGF.Builder.CreateGEP(overflow_arg_area, Offset,
3088                                             "overflow_arg_area.next");
3089   CGF.Builder.CreateStore(overflow_arg_area, overflow_arg_area_p);
3090 
3091   // AMD64-ABI 3.5.7p5: Step 11. Return the fetched type.
3092   return Address(Res, CharUnits::fromQuantity(Align));
3093 }
3094 
3095 Address X86_64ABIInfo::EmitVAArg(CodeGenFunction &CGF, Address VAListAddr,
3096                                  QualType Ty) const {
3097   // Assume that va_list type is correct; should be pointer to LLVM type:
3098   // struct {
3099   //   i32 gp_offset;
3100   //   i32 fp_offset;
3101   //   i8* overflow_arg_area;
3102   //   i8* reg_save_area;
3103   // };
3104   unsigned neededInt, neededSSE;
3105 
3106   Ty = getContext().getCanonicalType(Ty);
3107   ABIArgInfo AI = classifyArgumentType(Ty, 0, neededInt, neededSSE,
3108                                        /*isNamedArg*/false);
3109 
3110   // AMD64-ABI 3.5.7p5: Step 1. Determine whether type may be passed
3111   // in the registers. If not go to step 7.
3112   if (!neededInt && !neededSSE)
3113     return EmitX86_64VAArgFromMemory(CGF, VAListAddr, Ty);
3114 
3115   // AMD64-ABI 3.5.7p5: Step 2. Compute num_gp to hold the number of
3116   // general purpose registers needed to pass type and num_fp to hold
3117   // the number of floating point registers needed.
3118 
3119   // AMD64-ABI 3.5.7p5: Step 3. Verify whether arguments fit into
3120   // registers. In the case: l->gp_offset > 48 - num_gp * 8 or
3121   // l->fp_offset > 304 - num_fp * 16 go to step 7.
3122   //
3123   // NOTE: 304 is a typo, there are (6 * 8 + 8 * 16) = 176 bytes of
3124   // register save space).
3125 
3126   llvm::Value *InRegs = nullptr;
3127   Address gp_offset_p = Address::invalid(), fp_offset_p = Address::invalid();
3128   llvm::Value *gp_offset = nullptr, *fp_offset = nullptr;
3129   if (neededInt) {
3130     gp_offset_p =
3131         CGF.Builder.CreateStructGEP(VAListAddr, 0, CharUnits::Zero(),
3132                                     "gp_offset_p");
3133     gp_offset = CGF.Builder.CreateLoad(gp_offset_p, "gp_offset");
3134     InRegs = llvm::ConstantInt::get(CGF.Int32Ty, 48 - neededInt * 8);
3135     InRegs = CGF.Builder.CreateICmpULE(gp_offset, InRegs, "fits_in_gp");
3136   }
3137 
3138   if (neededSSE) {
3139     fp_offset_p =
3140         CGF.Builder.CreateStructGEP(VAListAddr, 1, CharUnits::fromQuantity(4),
3141                                     "fp_offset_p");
3142     fp_offset = CGF.Builder.CreateLoad(fp_offset_p, "fp_offset");
3143     llvm::Value *FitsInFP =
3144       llvm::ConstantInt::get(CGF.Int32Ty, 176 - neededSSE * 16);
3145     FitsInFP = CGF.Builder.CreateICmpULE(fp_offset, FitsInFP, "fits_in_fp");
3146     InRegs = InRegs ? CGF.Builder.CreateAnd(InRegs, FitsInFP) : FitsInFP;
3147   }
3148 
3149   llvm::BasicBlock *InRegBlock = CGF.createBasicBlock("vaarg.in_reg");
3150   llvm::BasicBlock *InMemBlock = CGF.createBasicBlock("vaarg.in_mem");
3151   llvm::BasicBlock *ContBlock = CGF.createBasicBlock("vaarg.end");
3152   CGF.Builder.CreateCondBr(InRegs, InRegBlock, InMemBlock);
3153 
3154   // Emit code to load the value if it was passed in registers.
3155 
3156   CGF.EmitBlock(InRegBlock);
3157 
3158   // AMD64-ABI 3.5.7p5: Step 4. Fetch type from l->reg_save_area with
3159   // an offset of l->gp_offset and/or l->fp_offset. This may require
3160   // copying to a temporary location in case the parameter is passed
3161   // in different register classes or requires an alignment greater
3162   // than 8 for general purpose registers and 16 for XMM registers.
3163   //
3164   // FIXME: This really results in shameful code when we end up needing to
3165   // collect arguments from different places; often what should result in a
3166   // simple assembling of a structure from scattered addresses has many more
3167   // loads than necessary. Can we clean this up?
3168   llvm::Type *LTy = CGF.ConvertTypeForMem(Ty);
3169   llvm::Value *RegSaveArea = CGF.Builder.CreateLoad(
3170       CGF.Builder.CreateStructGEP(VAListAddr, 3, CharUnits::fromQuantity(16)),
3171                                   "reg_save_area");
3172 
3173   Address RegAddr = Address::invalid();
3174   if (neededInt && neededSSE) {
3175     // FIXME: Cleanup.
3176     assert(AI.isDirect() && "Unexpected ABI info for mixed regs");
3177     llvm::StructType *ST = cast<llvm::StructType>(AI.getCoerceToType());
3178     Address Tmp = CGF.CreateMemTemp(Ty);
3179     Tmp = CGF.Builder.CreateElementBitCast(Tmp, ST);
3180     assert(ST->getNumElements() == 2 && "Unexpected ABI info for mixed regs");
3181     llvm::Type *TyLo = ST->getElementType(0);
3182     llvm::Type *TyHi = ST->getElementType(1);
3183     assert((TyLo->isFPOrFPVectorTy() ^ TyHi->isFPOrFPVectorTy()) &&
3184            "Unexpected ABI info for mixed regs");
3185     llvm::Type *PTyLo = llvm::PointerType::getUnqual(TyLo);
3186     llvm::Type *PTyHi = llvm::PointerType::getUnqual(TyHi);
3187     llvm::Value *GPAddr = CGF.Builder.CreateGEP(RegSaveArea, gp_offset);
3188     llvm::Value *FPAddr = CGF.Builder.CreateGEP(RegSaveArea, fp_offset);
3189     llvm::Value *RegLoAddr = TyLo->isFPOrFPVectorTy() ? FPAddr : GPAddr;
3190     llvm::Value *RegHiAddr = TyLo->isFPOrFPVectorTy() ? GPAddr : FPAddr;
3191 
3192     // Copy the first element.
3193     llvm::Value *V =
3194       CGF.Builder.CreateDefaultAlignedLoad(
3195                                CGF.Builder.CreateBitCast(RegLoAddr, PTyLo));
3196     CGF.Builder.CreateStore(V,
3197                     CGF.Builder.CreateStructGEP(Tmp, 0, CharUnits::Zero()));
3198 
3199     // Copy the second element.
3200     V = CGF.Builder.CreateDefaultAlignedLoad(
3201                                CGF.Builder.CreateBitCast(RegHiAddr, PTyHi));
3202     CharUnits Offset = CharUnits::fromQuantity(
3203                    getDataLayout().getStructLayout(ST)->getElementOffset(1));
3204     CGF.Builder.CreateStore(V, CGF.Builder.CreateStructGEP(Tmp, 1, Offset));
3205 
3206     RegAddr = CGF.Builder.CreateElementBitCast(Tmp, LTy);
3207   } else if (neededInt) {
3208     RegAddr = Address(CGF.Builder.CreateGEP(RegSaveArea, gp_offset),
3209                       CharUnits::fromQuantity(8));
3210     RegAddr = CGF.Builder.CreateElementBitCast(RegAddr, LTy);
3211 
3212     // Copy to a temporary if necessary to ensure the appropriate alignment.
3213     std::pair<CharUnits, CharUnits> SizeAlign =
3214         getContext().getTypeInfoInChars(Ty);
3215     uint64_t TySize = SizeAlign.first.getQuantity();
3216     CharUnits TyAlign = SizeAlign.second;
3217 
3218     // Copy into a temporary if the type is more aligned than the
3219     // register save area.
3220     if (TyAlign.getQuantity() > 8) {
3221       Address Tmp = CGF.CreateMemTemp(Ty);
3222       CGF.Builder.CreateMemCpy(Tmp, RegAddr, TySize, false);
3223       RegAddr = Tmp;
3224     }
3225 
3226   } else if (neededSSE == 1) {
3227     RegAddr = Address(CGF.Builder.CreateGEP(RegSaveArea, fp_offset),
3228                       CharUnits::fromQuantity(16));
3229     RegAddr = CGF.Builder.CreateElementBitCast(RegAddr, LTy);
3230   } else {
3231     assert(neededSSE == 2 && "Invalid number of needed registers!");
3232     // SSE registers are spaced 16 bytes apart in the register save
3233     // area, we need to collect the two eightbytes together.
3234     // The ABI isn't explicit about this, but it seems reasonable
3235     // to assume that the slots are 16-byte aligned, since the stack is
3236     // naturally 16-byte aligned and the prologue is expected to store
3237     // all the SSE registers to the RSA.
3238     Address RegAddrLo = Address(CGF.Builder.CreateGEP(RegSaveArea, fp_offset),
3239                                 CharUnits::fromQuantity(16));
3240     Address RegAddrHi =
3241       CGF.Builder.CreateConstInBoundsByteGEP(RegAddrLo,
3242                                              CharUnits::fromQuantity(16));
3243     llvm::Type *DoubleTy = CGF.DoubleTy;
3244     llvm::StructType *ST = llvm::StructType::get(DoubleTy, DoubleTy, nullptr);
3245     llvm::Value *V;
3246     Address Tmp = CGF.CreateMemTemp(Ty);
3247     Tmp = CGF.Builder.CreateElementBitCast(Tmp, ST);
3248     V = CGF.Builder.CreateLoad(
3249                    CGF.Builder.CreateElementBitCast(RegAddrLo, DoubleTy));
3250     CGF.Builder.CreateStore(V,
3251                    CGF.Builder.CreateStructGEP(Tmp, 0, CharUnits::Zero()));
3252     V = CGF.Builder.CreateLoad(
3253                    CGF.Builder.CreateElementBitCast(RegAddrHi, DoubleTy));
3254     CGF.Builder.CreateStore(V,
3255           CGF.Builder.CreateStructGEP(Tmp, 1, CharUnits::fromQuantity(8)));
3256 
3257     RegAddr = CGF.Builder.CreateElementBitCast(Tmp, LTy);
3258   }
3259 
3260   // AMD64-ABI 3.5.7p5: Step 5. Set:
3261   // l->gp_offset = l->gp_offset + num_gp * 8
3262   // l->fp_offset = l->fp_offset + num_fp * 16.
3263   if (neededInt) {
3264     llvm::Value *Offset = llvm::ConstantInt::get(CGF.Int32Ty, neededInt * 8);
3265     CGF.Builder.CreateStore(CGF.Builder.CreateAdd(gp_offset, Offset),
3266                             gp_offset_p);
3267   }
3268   if (neededSSE) {
3269     llvm::Value *Offset = llvm::ConstantInt::get(CGF.Int32Ty, neededSSE * 16);
3270     CGF.Builder.CreateStore(CGF.Builder.CreateAdd(fp_offset, Offset),
3271                             fp_offset_p);
3272   }
3273   CGF.EmitBranch(ContBlock);
3274 
3275   // Emit code to load the value if it was passed in memory.
3276 
3277   CGF.EmitBlock(InMemBlock);
3278   Address MemAddr = EmitX86_64VAArgFromMemory(CGF, VAListAddr, Ty);
3279 
3280   // Return the appropriate result.
3281 
3282   CGF.EmitBlock(ContBlock);
3283   Address ResAddr = emitMergePHI(CGF, RegAddr, InRegBlock, MemAddr, InMemBlock,
3284                                  "vaarg.addr");
3285   return ResAddr;
3286 }
3287 
3288 Address X86_64ABIInfo::EmitMSVAArg(CodeGenFunction &CGF, Address VAListAddr,
3289                                    QualType Ty) const {
3290   return emitVoidPtrVAArg(CGF, VAListAddr, Ty, /*indirect*/ false,
3291                           CGF.getContext().getTypeInfoInChars(Ty),
3292                           CharUnits::fromQuantity(8),
3293                           /*allowHigherAlign*/ false);
3294 }
3295 
3296 ABIArgInfo WinX86_64ABIInfo::classify(QualType Ty, unsigned &FreeSSERegs,
3297                                       bool IsReturnType) const {
3298 
3299   if (Ty->isVoidType())
3300     return ABIArgInfo::getIgnore();
3301 
3302   if (const EnumType *EnumTy = Ty->getAs<EnumType>())
3303     Ty = EnumTy->getDecl()->getIntegerType();
3304 
3305   TypeInfo Info = getContext().getTypeInfo(Ty);
3306   uint64_t Width = Info.Width;
3307   unsigned Align = getContext().toCharUnitsFromBits(Info.Align).getQuantity();
3308 
3309   const RecordType *RT = Ty->getAs<RecordType>();
3310   if (RT) {
3311     if (!IsReturnType) {
3312       if (CGCXXABI::RecordArgABI RAA = getRecordArgABI(RT, getCXXABI()))
3313         return getNaturalAlignIndirect(Ty, RAA == CGCXXABI::RAA_DirectInMemory);
3314     }
3315 
3316     if (RT->getDecl()->hasFlexibleArrayMember())
3317       return getNaturalAlignIndirect(Ty, /*ByVal=*/false);
3318 
3319     // FIXME: mingw-w64-gcc emits 128-bit struct as i128
3320     if (Width == 128 && getTarget().getTriple().isWindowsGNUEnvironment())
3321       return ABIArgInfo::getDirect(llvm::IntegerType::get(getVMContext(),
3322                                                           Width));
3323   }
3324 
3325   // vectorcall adds the concept of a homogenous vector aggregate, similar to
3326   // other targets.
3327   const Type *Base = nullptr;
3328   uint64_t NumElts = 0;
3329   if (FreeSSERegs && isHomogeneousAggregate(Ty, Base, NumElts)) {
3330     if (FreeSSERegs >= NumElts) {
3331       FreeSSERegs -= NumElts;
3332       if (IsReturnType || Ty->isBuiltinType() || Ty->isVectorType())
3333         return ABIArgInfo::getDirect();
3334       return ABIArgInfo::getExpand();
3335     }
3336     return ABIArgInfo::getIndirect(CharUnits::fromQuantity(Align),
3337                                    /*ByVal=*/false);
3338   }
3339 
3340 
3341   if (Ty->isMemberPointerType()) {
3342     // If the member pointer is represented by an LLVM int or ptr, pass it
3343     // directly.
3344     llvm::Type *LLTy = CGT.ConvertType(Ty);
3345     if (LLTy->isPointerTy() || LLTy->isIntegerTy())
3346       return ABIArgInfo::getDirect();
3347   }
3348 
3349   if (RT || Ty->isAnyComplexType() || Ty->isMemberPointerType()) {
3350     // MS x64 ABI requirement: "Any argument that doesn't fit in 8 bytes, or is
3351     // not 1, 2, 4, or 8 bytes, must be passed by reference."
3352     if (Width > 64 || !llvm::isPowerOf2_64(Width))
3353       return getNaturalAlignIndirect(Ty, /*ByVal=*/false);
3354 
3355     // Otherwise, coerce it to a small integer.
3356     return ABIArgInfo::getDirect(llvm::IntegerType::get(getVMContext(), Width));
3357   }
3358 
3359   // Bool type is always extended to the ABI, other builtin types are not
3360   // extended.
3361   const BuiltinType *BT = Ty->getAs<BuiltinType>();
3362   if (BT && BT->getKind() == BuiltinType::Bool)
3363     return ABIArgInfo::getExtend();
3364 
3365   return ABIArgInfo::getDirect();
3366 }
3367 
3368 void WinX86_64ABIInfo::computeInfo(CGFunctionInfo &FI) const {
3369   bool IsVectorCall =
3370       FI.getCallingConvention() == llvm::CallingConv::X86_VectorCall;
3371 
3372   // We can use up to 4 SSE return registers with vectorcall.
3373   unsigned FreeSSERegs = IsVectorCall ? 4 : 0;
3374   if (!getCXXABI().classifyReturnType(FI))
3375     FI.getReturnInfo() = classify(FI.getReturnType(), FreeSSERegs, true);
3376 
3377   // We can use up to 6 SSE register parameters with vectorcall.
3378   FreeSSERegs = IsVectorCall ? 6 : 0;
3379   for (auto &I : FI.arguments())
3380     I.info = classify(I.type, FreeSSERegs, false);
3381 }
3382 
3383 Address WinX86_64ABIInfo::EmitVAArg(CodeGenFunction &CGF, Address VAListAddr,
3384                                     QualType Ty) const {
3385   return emitVoidPtrVAArg(CGF, VAListAddr, Ty, /*indirect*/ false,
3386                           CGF.getContext().getTypeInfoInChars(Ty),
3387                           CharUnits::fromQuantity(8),
3388                           /*allowHigherAlign*/ false);
3389 }
3390 
3391 // PowerPC-32
3392 namespace {
3393 /// PPC32_SVR4_ABIInfo - The 32-bit PowerPC ELF (SVR4) ABI information.
3394 class PPC32_SVR4_ABIInfo : public DefaultABIInfo {
3395 public:
3396   PPC32_SVR4_ABIInfo(CodeGen::CodeGenTypes &CGT) : DefaultABIInfo(CGT) {}
3397 
3398   Address EmitVAArg(CodeGenFunction &CGF, Address VAListAddr,
3399                     QualType Ty) const override;
3400 };
3401 
3402 class PPC32TargetCodeGenInfo : public TargetCodeGenInfo {
3403 public:
3404   PPC32TargetCodeGenInfo(CodeGenTypes &CGT)
3405       : TargetCodeGenInfo(new PPC32_SVR4_ABIInfo(CGT)) {}
3406 
3407   int getDwarfEHStackPointer(CodeGen::CodeGenModule &M) const override {
3408     // This is recovered from gcc output.
3409     return 1; // r1 is the dedicated stack pointer
3410   }
3411 
3412   bool initDwarfEHRegSizeTable(CodeGen::CodeGenFunction &CGF,
3413                                llvm::Value *Address) const override;
3414 };
3415 
3416 }
3417 
3418 Address PPC32_SVR4_ABIInfo::EmitVAArg(CodeGenFunction &CGF, Address VAList,
3419                                       QualType Ty) const {
3420   if (const ComplexType *CTy = Ty->getAs<ComplexType>()) {
3421     // TODO: Implement this. For now ignore.
3422     (void)CTy;
3423     return Address::invalid();
3424   }
3425 
3426   // struct __va_list_tag {
3427   //   unsigned char gpr;
3428   //   unsigned char fpr;
3429   //   unsigned short reserved;
3430   //   void *overflow_arg_area;
3431   //   void *reg_save_area;
3432   // };
3433 
3434   bool isI64 = Ty->isIntegerType() && getContext().getTypeSize(Ty) == 64;
3435   bool isInt =
3436       Ty->isIntegerType() || Ty->isPointerType() || Ty->isAggregateType();
3437 
3438   // All aggregates are passed indirectly?  That doesn't seem consistent
3439   // with the argument-lowering code.
3440   bool isIndirect = Ty->isAggregateType();
3441 
3442   CGBuilderTy &Builder = CGF.Builder;
3443 
3444   // The calling convention either uses 1-2 GPRs or 1 FPR.
3445   Address NumRegsAddr = Address::invalid();
3446   if (isInt) {
3447     NumRegsAddr = Builder.CreateStructGEP(VAList, 0, CharUnits::Zero(), "gpr");
3448   } else {
3449     NumRegsAddr = Builder.CreateStructGEP(VAList, 1, CharUnits::One(), "fpr");
3450   }
3451 
3452   llvm::Value *NumRegs = Builder.CreateLoad(NumRegsAddr, "numUsedRegs");
3453 
3454   // "Align" the register count when TY is i64.
3455   if (isI64) {
3456     NumRegs = Builder.CreateAdd(NumRegs, Builder.getInt8(1));
3457     NumRegs = Builder.CreateAnd(NumRegs, Builder.getInt8((uint8_t) ~1U));
3458   }
3459 
3460   llvm::Value *CC =
3461       Builder.CreateICmpULT(NumRegs, Builder.getInt8(8), "cond");
3462 
3463   llvm::BasicBlock *UsingRegs = CGF.createBasicBlock("using_regs");
3464   llvm::BasicBlock *UsingOverflow = CGF.createBasicBlock("using_overflow");
3465   llvm::BasicBlock *Cont = CGF.createBasicBlock("cont");
3466 
3467   Builder.CreateCondBr(CC, UsingRegs, UsingOverflow);
3468 
3469   llvm::Type *DirectTy = CGF.ConvertType(Ty);
3470   if (isIndirect) DirectTy = DirectTy->getPointerTo(0);
3471 
3472   // Case 1: consume registers.
3473   Address RegAddr = Address::invalid();
3474   {
3475     CGF.EmitBlock(UsingRegs);
3476 
3477     Address RegSaveAreaPtr =
3478       Builder.CreateStructGEP(VAList, 4, CharUnits::fromQuantity(8));
3479     RegAddr = Address(Builder.CreateLoad(RegSaveAreaPtr),
3480                       CharUnits::fromQuantity(8));
3481     assert(RegAddr.getElementType() == CGF.Int8Ty);
3482 
3483     // Floating-point registers start after the general-purpose registers.
3484     if (!isInt) {
3485       RegAddr = Builder.CreateConstInBoundsByteGEP(RegAddr,
3486                                                    CharUnits::fromQuantity(32));
3487     }
3488 
3489     // Get the address of the saved value by scaling the number of
3490     // registers we've used by the number of
3491     CharUnits RegSize = CharUnits::fromQuantity(isInt ? 4 : 8);
3492     llvm::Value *RegOffset =
3493       Builder.CreateMul(NumRegs, Builder.getInt8(RegSize.getQuantity()));
3494     RegAddr = Address(Builder.CreateInBoundsGEP(CGF.Int8Ty,
3495                                             RegAddr.getPointer(), RegOffset),
3496                       RegAddr.getAlignment().alignmentOfArrayElement(RegSize));
3497     RegAddr = Builder.CreateElementBitCast(RegAddr, DirectTy);
3498 
3499     // Increase the used-register count.
3500     NumRegs = Builder.CreateAdd(NumRegs, Builder.getInt8(isI64 ? 2 : 1));
3501     Builder.CreateStore(NumRegs, NumRegsAddr);
3502 
3503     CGF.EmitBranch(Cont);
3504   }
3505 
3506   // Case 2: consume space in the overflow area.
3507   Address MemAddr = Address::invalid();
3508   {
3509     CGF.EmitBlock(UsingOverflow);
3510 
3511     // Everything in the overflow area is rounded up to a size of at least 4.
3512     CharUnits OverflowAreaAlign = CharUnits::fromQuantity(4);
3513 
3514     CharUnits Size;
3515     if (!isIndirect) {
3516       auto TypeInfo = CGF.getContext().getTypeInfoInChars(Ty);
3517       Size = TypeInfo.first.RoundUpToAlignment(OverflowAreaAlign);
3518     } else {
3519       Size = CGF.getPointerSize();
3520     }
3521 
3522     Address OverflowAreaAddr =
3523       Builder.CreateStructGEP(VAList, 3, CharUnits::fromQuantity(4));
3524     Address OverflowArea(Builder.CreateLoad(OverflowAreaAddr),
3525                          OverflowAreaAlign);
3526 
3527     // The current address is the address of the varargs element.
3528     // FIXME: do we not need to round up to alignment?
3529     MemAddr = Builder.CreateElementBitCast(OverflowArea, DirectTy);
3530 
3531     // Increase the overflow area.
3532     OverflowArea = Builder.CreateConstInBoundsByteGEP(OverflowArea, Size);
3533     Builder.CreateStore(OverflowArea.getPointer(), OverflowAreaAddr);
3534     CGF.EmitBranch(Cont);
3535   }
3536 
3537   CGF.EmitBlock(Cont);
3538 
3539   // Merge the cases with a phi.
3540   Address Result = emitMergePHI(CGF, RegAddr, UsingRegs, MemAddr, UsingOverflow,
3541                                 "vaarg.addr");
3542 
3543   // Load the pointer if the argument was passed indirectly.
3544   if (isIndirect) {
3545     Result = Address(Builder.CreateLoad(Result, "aggr"),
3546                      getContext().getTypeAlignInChars(Ty));
3547   }
3548 
3549   return Result;
3550 }
3551 
3552 bool
3553 PPC32TargetCodeGenInfo::initDwarfEHRegSizeTable(CodeGen::CodeGenFunction &CGF,
3554                                                 llvm::Value *Address) const {
3555   // This is calculated from the LLVM and GCC tables and verified
3556   // against gcc output.  AFAIK all ABIs use the same encoding.
3557 
3558   CodeGen::CGBuilderTy &Builder = CGF.Builder;
3559 
3560   llvm::IntegerType *i8 = CGF.Int8Ty;
3561   llvm::Value *Four8 = llvm::ConstantInt::get(i8, 4);
3562   llvm::Value *Eight8 = llvm::ConstantInt::get(i8, 8);
3563   llvm::Value *Sixteen8 = llvm::ConstantInt::get(i8, 16);
3564 
3565   // 0-31: r0-31, the 4-byte general-purpose registers
3566   AssignToArrayRange(Builder, Address, Four8, 0, 31);
3567 
3568   // 32-63: fp0-31, the 8-byte floating-point registers
3569   AssignToArrayRange(Builder, Address, Eight8, 32, 63);
3570 
3571   // 64-76 are various 4-byte special-purpose registers:
3572   // 64: mq
3573   // 65: lr
3574   // 66: ctr
3575   // 67: ap
3576   // 68-75 cr0-7
3577   // 76: xer
3578   AssignToArrayRange(Builder, Address, Four8, 64, 76);
3579 
3580   // 77-108: v0-31, the 16-byte vector registers
3581   AssignToArrayRange(Builder, Address, Sixteen8, 77, 108);
3582 
3583   // 109: vrsave
3584   // 110: vscr
3585   // 111: spe_acc
3586   // 112: spefscr
3587   // 113: sfp
3588   AssignToArrayRange(Builder, Address, Four8, 109, 113);
3589 
3590   return false;
3591 }
3592 
3593 // PowerPC-64
3594 
3595 namespace {
3596 /// PPC64_SVR4_ABIInfo - The 64-bit PowerPC ELF (SVR4) ABI information.
3597 class PPC64_SVR4_ABIInfo : public DefaultABIInfo {
3598 public:
3599   enum ABIKind {
3600     ELFv1 = 0,
3601     ELFv2
3602   };
3603 
3604 private:
3605   static const unsigned GPRBits = 64;
3606   ABIKind Kind;
3607   bool HasQPX;
3608 
3609   // A vector of float or double will be promoted to <4 x f32> or <4 x f64> and
3610   // will be passed in a QPX register.
3611   bool IsQPXVectorTy(const Type *Ty) const {
3612     if (!HasQPX)
3613       return false;
3614 
3615     if (const VectorType *VT = Ty->getAs<VectorType>()) {
3616       unsigned NumElements = VT->getNumElements();
3617       if (NumElements == 1)
3618         return false;
3619 
3620       if (VT->getElementType()->isSpecificBuiltinType(BuiltinType::Double)) {
3621         if (getContext().getTypeSize(Ty) <= 256)
3622           return true;
3623       } else if (VT->getElementType()->
3624                    isSpecificBuiltinType(BuiltinType::Float)) {
3625         if (getContext().getTypeSize(Ty) <= 128)
3626           return true;
3627       }
3628     }
3629 
3630     return false;
3631   }
3632 
3633   bool IsQPXVectorTy(QualType Ty) const {
3634     return IsQPXVectorTy(Ty.getTypePtr());
3635   }
3636 
3637 public:
3638   PPC64_SVR4_ABIInfo(CodeGen::CodeGenTypes &CGT, ABIKind Kind, bool HasQPX)
3639     : DefaultABIInfo(CGT), Kind(Kind), HasQPX(HasQPX) {}
3640 
3641   bool isPromotableTypeForABI(QualType Ty) const;
3642   CharUnits getParamTypeAlignment(QualType Ty) const;
3643 
3644   ABIArgInfo classifyReturnType(QualType RetTy) const;
3645   ABIArgInfo classifyArgumentType(QualType Ty) const;
3646 
3647   bool isHomogeneousAggregateBaseType(QualType Ty) const override;
3648   bool isHomogeneousAggregateSmallEnough(const Type *Ty,
3649                                          uint64_t Members) const override;
3650 
3651   // TODO: We can add more logic to computeInfo to improve performance.
3652   // Example: For aggregate arguments that fit in a register, we could
3653   // use getDirectInReg (as is done below for structs containing a single
3654   // floating-point value) to avoid pushing them to memory on function
3655   // entry.  This would require changing the logic in PPCISelLowering
3656   // when lowering the parameters in the caller and args in the callee.
3657   void computeInfo(CGFunctionInfo &FI) const override {
3658     if (!getCXXABI().classifyReturnType(FI))
3659       FI.getReturnInfo() = classifyReturnType(FI.getReturnType());
3660     for (auto &I : FI.arguments()) {
3661       // We rely on the default argument classification for the most part.
3662       // One exception:  An aggregate containing a single floating-point
3663       // or vector item must be passed in a register if one is available.
3664       const Type *T = isSingleElementStruct(I.type, getContext());
3665       if (T) {
3666         const BuiltinType *BT = T->getAs<BuiltinType>();
3667         if (IsQPXVectorTy(T) ||
3668             (T->isVectorType() && getContext().getTypeSize(T) == 128) ||
3669             (BT && BT->isFloatingPoint())) {
3670           QualType QT(T, 0);
3671           I.info = ABIArgInfo::getDirectInReg(CGT.ConvertType(QT));
3672           continue;
3673         }
3674       }
3675       I.info = classifyArgumentType(I.type);
3676     }
3677   }
3678 
3679   Address EmitVAArg(CodeGenFunction &CGF, Address VAListAddr,
3680                     QualType Ty) const override;
3681 };
3682 
3683 class PPC64_SVR4_TargetCodeGenInfo : public TargetCodeGenInfo {
3684 
3685 public:
3686   PPC64_SVR4_TargetCodeGenInfo(CodeGenTypes &CGT,
3687                                PPC64_SVR4_ABIInfo::ABIKind Kind, bool HasQPX)
3688       : TargetCodeGenInfo(new PPC64_SVR4_ABIInfo(CGT, Kind, HasQPX)) {}
3689 
3690   int getDwarfEHStackPointer(CodeGen::CodeGenModule &M) const override {
3691     // This is recovered from gcc output.
3692     return 1; // r1 is the dedicated stack pointer
3693   }
3694 
3695   bool initDwarfEHRegSizeTable(CodeGen::CodeGenFunction &CGF,
3696                                llvm::Value *Address) const override;
3697 };
3698 
3699 class PPC64TargetCodeGenInfo : public DefaultTargetCodeGenInfo {
3700 public:
3701   PPC64TargetCodeGenInfo(CodeGenTypes &CGT) : DefaultTargetCodeGenInfo(CGT) {}
3702 
3703   int getDwarfEHStackPointer(CodeGen::CodeGenModule &M) const override {
3704     // This is recovered from gcc output.
3705     return 1; // r1 is the dedicated stack pointer
3706   }
3707 
3708   bool initDwarfEHRegSizeTable(CodeGen::CodeGenFunction &CGF,
3709                                llvm::Value *Address) const override;
3710 };
3711 
3712 }
3713 
3714 // Return true if the ABI requires Ty to be passed sign- or zero-
3715 // extended to 64 bits.
3716 bool
3717 PPC64_SVR4_ABIInfo::isPromotableTypeForABI(QualType Ty) const {
3718   // Treat an enum type as its underlying type.
3719   if (const EnumType *EnumTy = Ty->getAs<EnumType>())
3720     Ty = EnumTy->getDecl()->getIntegerType();
3721 
3722   // Promotable integer types are required to be promoted by the ABI.
3723   if (Ty->isPromotableIntegerType())
3724     return true;
3725 
3726   // In addition to the usual promotable integer types, we also need to
3727   // extend all 32-bit types, since the ABI requires promotion to 64 bits.
3728   if (const BuiltinType *BT = Ty->getAs<BuiltinType>())
3729     switch (BT->getKind()) {
3730     case BuiltinType::Int:
3731     case BuiltinType::UInt:
3732       return true;
3733     default:
3734       break;
3735     }
3736 
3737   return false;
3738 }
3739 
3740 /// isAlignedParamType - Determine whether a type requires 16-byte or
3741 /// higher alignment in the parameter area.  Always returns at least 8.
3742 CharUnits PPC64_SVR4_ABIInfo::getParamTypeAlignment(QualType Ty) const {
3743   // Complex types are passed just like their elements.
3744   if (const ComplexType *CTy = Ty->getAs<ComplexType>())
3745     Ty = CTy->getElementType();
3746 
3747   // Only vector types of size 16 bytes need alignment (larger types are
3748   // passed via reference, smaller types are not aligned).
3749   if (IsQPXVectorTy(Ty)) {
3750     if (getContext().getTypeSize(Ty) > 128)
3751       return CharUnits::fromQuantity(32);
3752 
3753     return CharUnits::fromQuantity(16);
3754   } else if (Ty->isVectorType()) {
3755     return CharUnits::fromQuantity(getContext().getTypeSize(Ty) == 128 ? 16 : 8);
3756   }
3757 
3758   // For single-element float/vector structs, we consider the whole type
3759   // to have the same alignment requirements as its single element.
3760   const Type *AlignAsType = nullptr;
3761   const Type *EltType = isSingleElementStruct(Ty, getContext());
3762   if (EltType) {
3763     const BuiltinType *BT = EltType->getAs<BuiltinType>();
3764     if (IsQPXVectorTy(EltType) || (EltType->isVectorType() &&
3765          getContext().getTypeSize(EltType) == 128) ||
3766         (BT && BT->isFloatingPoint()))
3767       AlignAsType = EltType;
3768   }
3769 
3770   // Likewise for ELFv2 homogeneous aggregates.
3771   const Type *Base = nullptr;
3772   uint64_t Members = 0;
3773   if (!AlignAsType && Kind == ELFv2 &&
3774       isAggregateTypeForABI(Ty) && isHomogeneousAggregate(Ty, Base, Members))
3775     AlignAsType = Base;
3776 
3777   // With special case aggregates, only vector base types need alignment.
3778   if (AlignAsType && IsQPXVectorTy(AlignAsType)) {
3779     if (getContext().getTypeSize(AlignAsType) > 128)
3780       return CharUnits::fromQuantity(32);
3781 
3782     return CharUnits::fromQuantity(16);
3783   } else if (AlignAsType) {
3784     return CharUnits::fromQuantity(AlignAsType->isVectorType() ? 16 : 8);
3785   }
3786 
3787   // Otherwise, we only need alignment for any aggregate type that
3788   // has an alignment requirement of >= 16 bytes.
3789   if (isAggregateTypeForABI(Ty) && getContext().getTypeAlign(Ty) >= 128) {
3790     if (HasQPX && getContext().getTypeAlign(Ty) >= 256)
3791       return CharUnits::fromQuantity(32);
3792     return CharUnits::fromQuantity(16);
3793   }
3794 
3795   return CharUnits::fromQuantity(8);
3796 }
3797 
3798 /// isHomogeneousAggregate - Return true if a type is an ELFv2 homogeneous
3799 /// aggregate.  Base is set to the base element type, and Members is set
3800 /// to the number of base elements.
3801 bool ABIInfo::isHomogeneousAggregate(QualType Ty, const Type *&Base,
3802                                      uint64_t &Members) const {
3803   if (const ConstantArrayType *AT = getContext().getAsConstantArrayType(Ty)) {
3804     uint64_t NElements = AT->getSize().getZExtValue();
3805     if (NElements == 0)
3806       return false;
3807     if (!isHomogeneousAggregate(AT->getElementType(), Base, Members))
3808       return false;
3809     Members *= NElements;
3810   } else if (const RecordType *RT = Ty->getAs<RecordType>()) {
3811     const RecordDecl *RD = RT->getDecl();
3812     if (RD->hasFlexibleArrayMember())
3813       return false;
3814 
3815     Members = 0;
3816 
3817     // If this is a C++ record, check the bases first.
3818     if (const CXXRecordDecl *CXXRD = dyn_cast<CXXRecordDecl>(RD)) {
3819       for (const auto &I : CXXRD->bases()) {
3820         // Ignore empty records.
3821         if (isEmptyRecord(getContext(), I.getType(), true))
3822           continue;
3823 
3824         uint64_t FldMembers;
3825         if (!isHomogeneousAggregate(I.getType(), Base, FldMembers))
3826           return false;
3827 
3828         Members += FldMembers;
3829       }
3830     }
3831 
3832     for (const auto *FD : RD->fields()) {
3833       // Ignore (non-zero arrays of) empty records.
3834       QualType FT = FD->getType();
3835       while (const ConstantArrayType *AT =
3836              getContext().getAsConstantArrayType(FT)) {
3837         if (AT->getSize().getZExtValue() == 0)
3838           return false;
3839         FT = AT->getElementType();
3840       }
3841       if (isEmptyRecord(getContext(), FT, true))
3842         continue;
3843 
3844       // For compatibility with GCC, ignore empty bitfields in C++ mode.
3845       if (getContext().getLangOpts().CPlusPlus &&
3846           FD->isBitField() && FD->getBitWidthValue(getContext()) == 0)
3847         continue;
3848 
3849       uint64_t FldMembers;
3850       if (!isHomogeneousAggregate(FD->getType(), Base, FldMembers))
3851         return false;
3852 
3853       Members = (RD->isUnion() ?
3854                  std::max(Members, FldMembers) : Members + FldMembers);
3855     }
3856 
3857     if (!Base)
3858       return false;
3859 
3860     // Ensure there is no padding.
3861     if (getContext().getTypeSize(Base) * Members !=
3862         getContext().getTypeSize(Ty))
3863       return false;
3864   } else {
3865     Members = 1;
3866     if (const ComplexType *CT = Ty->getAs<ComplexType>()) {
3867       Members = 2;
3868       Ty = CT->getElementType();
3869     }
3870 
3871     // Most ABIs only support float, double, and some vector type widths.
3872     if (!isHomogeneousAggregateBaseType(Ty))
3873       return false;
3874 
3875     // The base type must be the same for all members.  Types that
3876     // agree in both total size and mode (float vs. vector) are
3877     // treated as being equivalent here.
3878     const Type *TyPtr = Ty.getTypePtr();
3879     if (!Base)
3880       Base = TyPtr;
3881 
3882     if (Base->isVectorType() != TyPtr->isVectorType() ||
3883         getContext().getTypeSize(Base) != getContext().getTypeSize(TyPtr))
3884       return false;
3885   }
3886   return Members > 0 && isHomogeneousAggregateSmallEnough(Base, Members);
3887 }
3888 
3889 bool PPC64_SVR4_ABIInfo::isHomogeneousAggregateBaseType(QualType Ty) const {
3890   // Homogeneous aggregates for ELFv2 must have base types of float,
3891   // double, long double, or 128-bit vectors.
3892   if (const BuiltinType *BT = Ty->getAs<BuiltinType>()) {
3893     if (BT->getKind() == BuiltinType::Float ||
3894         BT->getKind() == BuiltinType::Double ||
3895         BT->getKind() == BuiltinType::LongDouble)
3896       return true;
3897   }
3898   if (const VectorType *VT = Ty->getAs<VectorType>()) {
3899     if (getContext().getTypeSize(VT) == 128 || IsQPXVectorTy(Ty))
3900       return true;
3901   }
3902   return false;
3903 }
3904 
3905 bool PPC64_SVR4_ABIInfo::isHomogeneousAggregateSmallEnough(
3906     const Type *Base, uint64_t Members) const {
3907   // Vector types require one register, floating point types require one
3908   // or two registers depending on their size.
3909   uint32_t NumRegs =
3910       Base->isVectorType() ? 1 : (getContext().getTypeSize(Base) + 63) / 64;
3911 
3912   // Homogeneous Aggregates may occupy at most 8 registers.
3913   return Members * NumRegs <= 8;
3914 }
3915 
3916 ABIArgInfo
3917 PPC64_SVR4_ABIInfo::classifyArgumentType(QualType Ty) const {
3918   Ty = useFirstFieldIfTransparentUnion(Ty);
3919 
3920   if (Ty->isAnyComplexType())
3921     return ABIArgInfo::getDirect();
3922 
3923   // Non-Altivec vector types are passed in GPRs (smaller than 16 bytes)
3924   // or via reference (larger than 16 bytes).
3925   if (Ty->isVectorType() && !IsQPXVectorTy(Ty)) {
3926     uint64_t Size = getContext().getTypeSize(Ty);
3927     if (Size > 128)
3928       return getNaturalAlignIndirect(Ty, /*ByVal=*/false);
3929     else if (Size < 128) {
3930       llvm::Type *CoerceTy = llvm::IntegerType::get(getVMContext(), Size);
3931       return ABIArgInfo::getDirect(CoerceTy);
3932     }
3933   }
3934 
3935   if (isAggregateTypeForABI(Ty)) {
3936     if (CGCXXABI::RecordArgABI RAA = getRecordArgABI(Ty, getCXXABI()))
3937       return getNaturalAlignIndirect(Ty, RAA == CGCXXABI::RAA_DirectInMemory);
3938 
3939     uint64_t ABIAlign = getParamTypeAlignment(Ty).getQuantity();
3940     uint64_t TyAlign = getContext().getTypeAlignInChars(Ty).getQuantity();
3941 
3942     // ELFv2 homogeneous aggregates are passed as array types.
3943     const Type *Base = nullptr;
3944     uint64_t Members = 0;
3945     if (Kind == ELFv2 &&
3946         isHomogeneousAggregate(Ty, Base, Members)) {
3947       llvm::Type *BaseTy = CGT.ConvertType(QualType(Base, 0));
3948       llvm::Type *CoerceTy = llvm::ArrayType::get(BaseTy, Members);
3949       return ABIArgInfo::getDirect(CoerceTy);
3950     }
3951 
3952     // If an aggregate may end up fully in registers, we do not
3953     // use the ByVal method, but pass the aggregate as array.
3954     // This is usually beneficial since we avoid forcing the
3955     // back-end to store the argument to memory.
3956     uint64_t Bits = getContext().getTypeSize(Ty);
3957     if (Bits > 0 && Bits <= 8 * GPRBits) {
3958       llvm::Type *CoerceTy;
3959 
3960       // Types up to 8 bytes are passed as integer type (which will be
3961       // properly aligned in the argument save area doubleword).
3962       if (Bits <= GPRBits)
3963         CoerceTy = llvm::IntegerType::get(getVMContext(),
3964                                           llvm::RoundUpToAlignment(Bits, 8));
3965       // Larger types are passed as arrays, with the base type selected
3966       // according to the required alignment in the save area.
3967       else {
3968         uint64_t RegBits = ABIAlign * 8;
3969         uint64_t NumRegs = llvm::RoundUpToAlignment(Bits, RegBits) / RegBits;
3970         llvm::Type *RegTy = llvm::IntegerType::get(getVMContext(), RegBits);
3971         CoerceTy = llvm::ArrayType::get(RegTy, NumRegs);
3972       }
3973 
3974       return ABIArgInfo::getDirect(CoerceTy);
3975     }
3976 
3977     // All other aggregates are passed ByVal.
3978     return ABIArgInfo::getIndirect(CharUnits::fromQuantity(ABIAlign),
3979                                    /*ByVal=*/true,
3980                                    /*Realign=*/TyAlign > ABIAlign);
3981   }
3982 
3983   return (isPromotableTypeForABI(Ty) ?
3984           ABIArgInfo::getExtend() : ABIArgInfo::getDirect());
3985 }
3986 
3987 ABIArgInfo
3988 PPC64_SVR4_ABIInfo::classifyReturnType(QualType RetTy) const {
3989   if (RetTy->isVoidType())
3990     return ABIArgInfo::getIgnore();
3991 
3992   if (RetTy->isAnyComplexType())
3993     return ABIArgInfo::getDirect();
3994 
3995   // Non-Altivec vector types are returned in GPRs (smaller than 16 bytes)
3996   // or via reference (larger than 16 bytes).
3997   if (RetTy->isVectorType() && !IsQPXVectorTy(RetTy)) {
3998     uint64_t Size = getContext().getTypeSize(RetTy);
3999     if (Size > 128)
4000       return getNaturalAlignIndirect(RetTy);
4001     else if (Size < 128) {
4002       llvm::Type *CoerceTy = llvm::IntegerType::get(getVMContext(), Size);
4003       return ABIArgInfo::getDirect(CoerceTy);
4004     }
4005   }
4006 
4007   if (isAggregateTypeForABI(RetTy)) {
4008     // ELFv2 homogeneous aggregates are returned as array types.
4009     const Type *Base = nullptr;
4010     uint64_t Members = 0;
4011     if (Kind == ELFv2 &&
4012         isHomogeneousAggregate(RetTy, Base, Members)) {
4013       llvm::Type *BaseTy = CGT.ConvertType(QualType(Base, 0));
4014       llvm::Type *CoerceTy = llvm::ArrayType::get(BaseTy, Members);
4015       return ABIArgInfo::getDirect(CoerceTy);
4016     }
4017 
4018     // ELFv2 small aggregates are returned in up to two registers.
4019     uint64_t Bits = getContext().getTypeSize(RetTy);
4020     if (Kind == ELFv2 && Bits <= 2 * GPRBits) {
4021       if (Bits == 0)
4022         return ABIArgInfo::getIgnore();
4023 
4024       llvm::Type *CoerceTy;
4025       if (Bits > GPRBits) {
4026         CoerceTy = llvm::IntegerType::get(getVMContext(), GPRBits);
4027         CoerceTy = llvm::StructType::get(CoerceTy, CoerceTy, nullptr);
4028       } else
4029         CoerceTy = llvm::IntegerType::get(getVMContext(),
4030                                           llvm::RoundUpToAlignment(Bits, 8));
4031       return ABIArgInfo::getDirect(CoerceTy);
4032     }
4033 
4034     // All other aggregates are returned indirectly.
4035     return getNaturalAlignIndirect(RetTy);
4036   }
4037 
4038   return (isPromotableTypeForABI(RetTy) ?
4039           ABIArgInfo::getExtend() : ABIArgInfo::getDirect());
4040 }
4041 
4042 // Based on ARMABIInfo::EmitVAArg, adjusted for 64-bit machine.
4043 Address PPC64_SVR4_ABIInfo::EmitVAArg(CodeGenFunction &CGF, Address VAListAddr,
4044                                       QualType Ty) const {
4045   auto TypeInfo = getContext().getTypeInfoInChars(Ty);
4046   TypeInfo.second = getParamTypeAlignment(Ty);
4047 
4048   CharUnits SlotSize = CharUnits::fromQuantity(8);
4049 
4050   // If we have a complex type and the base type is smaller than 8 bytes,
4051   // the ABI calls for the real and imaginary parts to be right-adjusted
4052   // in separate doublewords.  However, Clang expects us to produce a
4053   // pointer to a structure with the two parts packed tightly.  So generate
4054   // loads of the real and imaginary parts relative to the va_list pointer,
4055   // and store them to a temporary structure.
4056   if (const ComplexType *CTy = Ty->getAs<ComplexType>()) {
4057     CharUnits EltSize = TypeInfo.first / 2;
4058     if (EltSize < SlotSize) {
4059       Address Addr = emitVoidPtrDirectVAArg(CGF, VAListAddr, CGF.Int8Ty,
4060                                             SlotSize * 2, SlotSize,
4061                                             SlotSize, /*AllowHigher*/ true);
4062 
4063       Address RealAddr = Addr;
4064       Address ImagAddr = RealAddr;
4065       if (CGF.CGM.getDataLayout().isBigEndian()) {
4066         RealAddr = CGF.Builder.CreateConstInBoundsByteGEP(RealAddr,
4067                                                           SlotSize - EltSize);
4068         ImagAddr = CGF.Builder.CreateConstInBoundsByteGEP(ImagAddr,
4069                                                       2 * SlotSize - EltSize);
4070       } else {
4071         ImagAddr = CGF.Builder.CreateConstInBoundsByteGEP(RealAddr, SlotSize);
4072       }
4073 
4074       llvm::Type *EltTy = CGF.ConvertTypeForMem(CTy->getElementType());
4075       RealAddr = CGF.Builder.CreateElementBitCast(RealAddr, EltTy);
4076       ImagAddr = CGF.Builder.CreateElementBitCast(ImagAddr, EltTy);
4077       llvm::Value *Real = CGF.Builder.CreateLoad(RealAddr, ".vareal");
4078       llvm::Value *Imag = CGF.Builder.CreateLoad(ImagAddr, ".vaimag");
4079 
4080       Address Temp = CGF.CreateMemTemp(Ty, "vacplx");
4081       CGF.EmitStoreOfComplex({Real, Imag}, CGF.MakeAddrLValue(Temp, Ty),
4082                              /*init*/ true);
4083       return Temp;
4084     }
4085   }
4086 
4087   // Otherwise, just use the general rule.
4088   return emitVoidPtrVAArg(CGF, VAListAddr, Ty, /*Indirect*/ false,
4089                           TypeInfo, SlotSize, /*AllowHigher*/ true);
4090 }
4091 
4092 static bool
4093 PPC64_initDwarfEHRegSizeTable(CodeGen::CodeGenFunction &CGF,
4094                               llvm::Value *Address) {
4095   // This is calculated from the LLVM and GCC tables and verified
4096   // against gcc output.  AFAIK all ABIs use the same encoding.
4097 
4098   CodeGen::CGBuilderTy &Builder = CGF.Builder;
4099 
4100   llvm::IntegerType *i8 = CGF.Int8Ty;
4101   llvm::Value *Four8 = llvm::ConstantInt::get(i8, 4);
4102   llvm::Value *Eight8 = llvm::ConstantInt::get(i8, 8);
4103   llvm::Value *Sixteen8 = llvm::ConstantInt::get(i8, 16);
4104 
4105   // 0-31: r0-31, the 8-byte general-purpose registers
4106   AssignToArrayRange(Builder, Address, Eight8, 0, 31);
4107 
4108   // 32-63: fp0-31, the 8-byte floating-point registers
4109   AssignToArrayRange(Builder, Address, Eight8, 32, 63);
4110 
4111   // 64-76 are various 4-byte special-purpose registers:
4112   // 64: mq
4113   // 65: lr
4114   // 66: ctr
4115   // 67: ap
4116   // 68-75 cr0-7
4117   // 76: xer
4118   AssignToArrayRange(Builder, Address, Four8, 64, 76);
4119 
4120   // 77-108: v0-31, the 16-byte vector registers
4121   AssignToArrayRange(Builder, Address, Sixteen8, 77, 108);
4122 
4123   // 109: vrsave
4124   // 110: vscr
4125   // 111: spe_acc
4126   // 112: spefscr
4127   // 113: sfp
4128   AssignToArrayRange(Builder, Address, Four8, 109, 113);
4129 
4130   return false;
4131 }
4132 
4133 bool
4134 PPC64_SVR4_TargetCodeGenInfo::initDwarfEHRegSizeTable(
4135   CodeGen::CodeGenFunction &CGF,
4136   llvm::Value *Address) const {
4137 
4138   return PPC64_initDwarfEHRegSizeTable(CGF, Address);
4139 }
4140 
4141 bool
4142 PPC64TargetCodeGenInfo::initDwarfEHRegSizeTable(CodeGen::CodeGenFunction &CGF,
4143                                                 llvm::Value *Address) const {
4144 
4145   return PPC64_initDwarfEHRegSizeTable(CGF, Address);
4146 }
4147 
4148 //===----------------------------------------------------------------------===//
4149 // AArch64 ABI Implementation
4150 //===----------------------------------------------------------------------===//
4151 
4152 namespace {
4153 
4154 class AArch64ABIInfo : public ABIInfo {
4155 public:
4156   enum ABIKind {
4157     AAPCS = 0,
4158     DarwinPCS
4159   };
4160 
4161 private:
4162   ABIKind Kind;
4163 
4164 public:
4165   AArch64ABIInfo(CodeGenTypes &CGT, ABIKind Kind) : ABIInfo(CGT), Kind(Kind) {}
4166 
4167 private:
4168   ABIKind getABIKind() const { return Kind; }
4169   bool isDarwinPCS() const { return Kind == DarwinPCS; }
4170 
4171   ABIArgInfo classifyReturnType(QualType RetTy) const;
4172   ABIArgInfo classifyArgumentType(QualType RetTy) const;
4173   bool isHomogeneousAggregateBaseType(QualType Ty) const override;
4174   bool isHomogeneousAggregateSmallEnough(const Type *Ty,
4175                                          uint64_t Members) const override;
4176 
4177   bool isIllegalVectorType(QualType Ty) const;
4178 
4179   void computeInfo(CGFunctionInfo &FI) const override {
4180     if (!getCXXABI().classifyReturnType(FI))
4181       FI.getReturnInfo() = classifyReturnType(FI.getReturnType());
4182 
4183     for (auto &it : FI.arguments())
4184       it.info = classifyArgumentType(it.type);
4185   }
4186 
4187   Address EmitDarwinVAArg(Address VAListAddr, QualType Ty,
4188                           CodeGenFunction &CGF) const;
4189 
4190   Address EmitAAPCSVAArg(Address VAListAddr, QualType Ty,
4191                          CodeGenFunction &CGF) const;
4192 
4193   Address EmitVAArg(CodeGenFunction &CGF, Address VAListAddr,
4194                     QualType Ty) const override {
4195     return isDarwinPCS() ? EmitDarwinVAArg(VAListAddr, Ty, CGF)
4196                          : EmitAAPCSVAArg(VAListAddr, Ty, CGF);
4197   }
4198 };
4199 
4200 class AArch64TargetCodeGenInfo : public TargetCodeGenInfo {
4201 public:
4202   AArch64TargetCodeGenInfo(CodeGenTypes &CGT, AArch64ABIInfo::ABIKind Kind)
4203       : TargetCodeGenInfo(new AArch64ABIInfo(CGT, Kind)) {}
4204 
4205   StringRef getARCRetainAutoreleasedReturnValueMarker() const override {
4206     return "mov\tfp, fp\t\t; marker for objc_retainAutoreleaseReturnValue";
4207   }
4208 
4209   int getDwarfEHStackPointer(CodeGen::CodeGenModule &M) const override {
4210     return 31;
4211   }
4212 
4213   bool doesReturnSlotInterfereWithArgs() const override { return false; }
4214 };
4215 }
4216 
4217 ABIArgInfo AArch64ABIInfo::classifyArgumentType(QualType Ty) const {
4218   Ty = useFirstFieldIfTransparentUnion(Ty);
4219 
4220   // Handle illegal vector types here.
4221   if (isIllegalVectorType(Ty)) {
4222     uint64_t Size = getContext().getTypeSize(Ty);
4223     if (Size <= 32) {
4224       llvm::Type *ResType = llvm::Type::getInt32Ty(getVMContext());
4225       return ABIArgInfo::getDirect(ResType);
4226     }
4227     if (Size == 64) {
4228       llvm::Type *ResType =
4229           llvm::VectorType::get(llvm::Type::getInt32Ty(getVMContext()), 2);
4230       return ABIArgInfo::getDirect(ResType);
4231     }
4232     if (Size == 128) {
4233       llvm::Type *ResType =
4234           llvm::VectorType::get(llvm::Type::getInt32Ty(getVMContext()), 4);
4235       return ABIArgInfo::getDirect(ResType);
4236     }
4237     return getNaturalAlignIndirect(Ty, /*ByVal=*/false);
4238   }
4239 
4240   if (!isAggregateTypeForABI(Ty)) {
4241     // Treat an enum type as its underlying type.
4242     if (const EnumType *EnumTy = Ty->getAs<EnumType>())
4243       Ty = EnumTy->getDecl()->getIntegerType();
4244 
4245     return (Ty->isPromotableIntegerType() && isDarwinPCS()
4246                 ? ABIArgInfo::getExtend()
4247                 : ABIArgInfo::getDirect());
4248   }
4249 
4250   // Structures with either a non-trivial destructor or a non-trivial
4251   // copy constructor are always indirect.
4252   if (CGCXXABI::RecordArgABI RAA = getRecordArgABI(Ty, getCXXABI())) {
4253     return getNaturalAlignIndirect(Ty, /*ByVal=*/RAA ==
4254                                      CGCXXABI::RAA_DirectInMemory);
4255   }
4256 
4257   // Empty records are always ignored on Darwin, but actually passed in C++ mode
4258   // elsewhere for GNU compatibility.
4259   if (isEmptyRecord(getContext(), Ty, true)) {
4260     if (!getContext().getLangOpts().CPlusPlus || isDarwinPCS())
4261       return ABIArgInfo::getIgnore();
4262 
4263     return ABIArgInfo::getDirect(llvm::Type::getInt8Ty(getVMContext()));
4264   }
4265 
4266   // Homogeneous Floating-point Aggregates (HFAs) need to be expanded.
4267   const Type *Base = nullptr;
4268   uint64_t Members = 0;
4269   if (isHomogeneousAggregate(Ty, Base, Members)) {
4270     return ABIArgInfo::getDirect(
4271         llvm::ArrayType::get(CGT.ConvertType(QualType(Base, 0)), Members));
4272   }
4273 
4274   // Aggregates <= 16 bytes are passed directly in registers or on the stack.
4275   uint64_t Size = getContext().getTypeSize(Ty);
4276   if (Size <= 128) {
4277     unsigned Alignment = getContext().getTypeAlign(Ty);
4278     Size = 64 * ((Size + 63) / 64); // round up to multiple of 8 bytes
4279 
4280     // We use a pair of i64 for 16-byte aggregate with 8-byte alignment.
4281     // For aggregates with 16-byte alignment, we use i128.
4282     if (Alignment < 128 && Size == 128) {
4283       llvm::Type *BaseTy = llvm::Type::getInt64Ty(getVMContext());
4284       return ABIArgInfo::getDirect(llvm::ArrayType::get(BaseTy, Size / 64));
4285     }
4286     return ABIArgInfo::getDirect(llvm::IntegerType::get(getVMContext(), Size));
4287   }
4288 
4289   return getNaturalAlignIndirect(Ty, /*ByVal=*/false);
4290 }
4291 
4292 ABIArgInfo AArch64ABIInfo::classifyReturnType(QualType RetTy) const {
4293   if (RetTy->isVoidType())
4294     return ABIArgInfo::getIgnore();
4295 
4296   // Large vector types should be returned via memory.
4297   if (RetTy->isVectorType() && getContext().getTypeSize(RetTy) > 128)
4298     return getNaturalAlignIndirect(RetTy);
4299 
4300   if (!isAggregateTypeForABI(RetTy)) {
4301     // Treat an enum type as its underlying type.
4302     if (const EnumType *EnumTy = RetTy->getAs<EnumType>())
4303       RetTy = EnumTy->getDecl()->getIntegerType();
4304 
4305     return (RetTy->isPromotableIntegerType() && isDarwinPCS()
4306                 ? ABIArgInfo::getExtend()
4307                 : ABIArgInfo::getDirect());
4308   }
4309 
4310   if (isEmptyRecord(getContext(), RetTy, true))
4311     return ABIArgInfo::getIgnore();
4312 
4313   const Type *Base = nullptr;
4314   uint64_t Members = 0;
4315   if (isHomogeneousAggregate(RetTy, Base, Members))
4316     // Homogeneous Floating-point Aggregates (HFAs) are returned directly.
4317     return ABIArgInfo::getDirect();
4318 
4319   // Aggregates <= 16 bytes are returned directly in registers or on the stack.
4320   uint64_t Size = getContext().getTypeSize(RetTy);
4321   if (Size <= 128) {
4322     unsigned Alignment = getContext().getTypeAlign(RetTy);
4323     Size = 64 * ((Size + 63) / 64); // round up to multiple of 8 bytes
4324 
4325     // We use a pair of i64 for 16-byte aggregate with 8-byte alignment.
4326     // For aggregates with 16-byte alignment, we use i128.
4327     if (Alignment < 128 && Size == 128) {
4328       llvm::Type *BaseTy = llvm::Type::getInt64Ty(getVMContext());
4329       return ABIArgInfo::getDirect(llvm::ArrayType::get(BaseTy, Size / 64));
4330     }
4331     return ABIArgInfo::getDirect(llvm::IntegerType::get(getVMContext(), Size));
4332   }
4333 
4334   return getNaturalAlignIndirect(RetTy);
4335 }
4336 
4337 /// isIllegalVectorType - check whether the vector type is legal for AArch64.
4338 bool AArch64ABIInfo::isIllegalVectorType(QualType Ty) const {
4339   if (const VectorType *VT = Ty->getAs<VectorType>()) {
4340     // Check whether VT is legal.
4341     unsigned NumElements = VT->getNumElements();
4342     uint64_t Size = getContext().getTypeSize(VT);
4343     // NumElements should be power of 2 between 1 and 16.
4344     if ((NumElements & (NumElements - 1)) != 0 || NumElements > 16)
4345       return true;
4346     return Size != 64 && (Size != 128 || NumElements == 1);
4347   }
4348   return false;
4349 }
4350 
4351 bool AArch64ABIInfo::isHomogeneousAggregateBaseType(QualType Ty) const {
4352   // Homogeneous aggregates for AAPCS64 must have base types of a floating
4353   // point type or a short-vector type. This is the same as the 32-bit ABI,
4354   // but with the difference that any floating-point type is allowed,
4355   // including __fp16.
4356   if (const BuiltinType *BT = Ty->getAs<BuiltinType>()) {
4357     if (BT->isFloatingPoint())
4358       return true;
4359   } else if (const VectorType *VT = Ty->getAs<VectorType>()) {
4360     unsigned VecSize = getContext().getTypeSize(VT);
4361     if (VecSize == 64 || VecSize == 128)
4362       return true;
4363   }
4364   return false;
4365 }
4366 
4367 bool AArch64ABIInfo::isHomogeneousAggregateSmallEnough(const Type *Base,
4368                                                        uint64_t Members) const {
4369   return Members <= 4;
4370 }
4371 
4372 Address AArch64ABIInfo::EmitAAPCSVAArg(Address VAListAddr,
4373                                             QualType Ty,
4374                                             CodeGenFunction &CGF) const {
4375   ABIArgInfo AI = classifyArgumentType(Ty);
4376   bool IsIndirect = AI.isIndirect();
4377 
4378   llvm::Type *BaseTy = CGF.ConvertType(Ty);
4379   if (IsIndirect)
4380     BaseTy = llvm::PointerType::getUnqual(BaseTy);
4381   else if (AI.getCoerceToType())
4382     BaseTy = AI.getCoerceToType();
4383 
4384   unsigned NumRegs = 1;
4385   if (llvm::ArrayType *ArrTy = dyn_cast<llvm::ArrayType>(BaseTy)) {
4386     BaseTy = ArrTy->getElementType();
4387     NumRegs = ArrTy->getNumElements();
4388   }
4389   bool IsFPR = BaseTy->isFloatingPointTy() || BaseTy->isVectorTy();
4390 
4391   // The AArch64 va_list type and handling is specified in the Procedure Call
4392   // Standard, section B.4:
4393   //
4394   // struct {
4395   //   void *__stack;
4396   //   void *__gr_top;
4397   //   void *__vr_top;
4398   //   int __gr_offs;
4399   //   int __vr_offs;
4400   // };
4401 
4402   llvm::BasicBlock *MaybeRegBlock = CGF.createBasicBlock("vaarg.maybe_reg");
4403   llvm::BasicBlock *InRegBlock = CGF.createBasicBlock("vaarg.in_reg");
4404   llvm::BasicBlock *OnStackBlock = CGF.createBasicBlock("vaarg.on_stack");
4405   llvm::BasicBlock *ContBlock = CGF.createBasicBlock("vaarg.end");
4406 
4407   auto TyInfo = getContext().getTypeInfoInChars(Ty);
4408   CharUnits TyAlign = TyInfo.second;
4409 
4410   Address reg_offs_p = Address::invalid();
4411   llvm::Value *reg_offs = nullptr;
4412   int reg_top_index;
4413   CharUnits reg_top_offset;
4414   int RegSize = IsIndirect ? 8 : TyInfo.first.getQuantity();
4415   if (!IsFPR) {
4416     // 3 is the field number of __gr_offs
4417     reg_offs_p =
4418         CGF.Builder.CreateStructGEP(VAListAddr, 3, CharUnits::fromQuantity(24),
4419                                     "gr_offs_p");
4420     reg_offs = CGF.Builder.CreateLoad(reg_offs_p, "gr_offs");
4421     reg_top_index = 1; // field number for __gr_top
4422     reg_top_offset = CharUnits::fromQuantity(8);
4423     RegSize = llvm::RoundUpToAlignment(RegSize, 8);
4424   } else {
4425     // 4 is the field number of __vr_offs.
4426     reg_offs_p =
4427         CGF.Builder.CreateStructGEP(VAListAddr, 4, CharUnits::fromQuantity(28),
4428                                     "vr_offs_p");
4429     reg_offs = CGF.Builder.CreateLoad(reg_offs_p, "vr_offs");
4430     reg_top_index = 2; // field number for __vr_top
4431     reg_top_offset = CharUnits::fromQuantity(16);
4432     RegSize = 16 * NumRegs;
4433   }
4434 
4435   //=======================================
4436   // Find out where argument was passed
4437   //=======================================
4438 
4439   // If reg_offs >= 0 we're already using the stack for this type of
4440   // argument. We don't want to keep updating reg_offs (in case it overflows,
4441   // though anyone passing 2GB of arguments, each at most 16 bytes, deserves
4442   // whatever they get).
4443   llvm::Value *UsingStack = nullptr;
4444   UsingStack = CGF.Builder.CreateICmpSGE(
4445       reg_offs, llvm::ConstantInt::get(CGF.Int32Ty, 0));
4446 
4447   CGF.Builder.CreateCondBr(UsingStack, OnStackBlock, MaybeRegBlock);
4448 
4449   // Otherwise, at least some kind of argument could go in these registers, the
4450   // question is whether this particular type is too big.
4451   CGF.EmitBlock(MaybeRegBlock);
4452 
4453   // Integer arguments may need to correct register alignment (for example a
4454   // "struct { __int128 a; };" gets passed in x_2N, x_{2N+1}). In this case we
4455   // align __gr_offs to calculate the potential address.
4456   if (!IsFPR && !IsIndirect && TyAlign.getQuantity() > 8) {
4457     int Align = TyAlign.getQuantity();
4458 
4459     reg_offs = CGF.Builder.CreateAdd(
4460         reg_offs, llvm::ConstantInt::get(CGF.Int32Ty, Align - 1),
4461         "align_regoffs");
4462     reg_offs = CGF.Builder.CreateAnd(
4463         reg_offs, llvm::ConstantInt::get(CGF.Int32Ty, -Align),
4464         "aligned_regoffs");
4465   }
4466 
4467   // Update the gr_offs/vr_offs pointer for next call to va_arg on this va_list.
4468   // The fact that this is done unconditionally reflects the fact that
4469   // allocating an argument to the stack also uses up all the remaining
4470   // registers of the appropriate kind.
4471   llvm::Value *NewOffset = nullptr;
4472   NewOffset = CGF.Builder.CreateAdd(
4473       reg_offs, llvm::ConstantInt::get(CGF.Int32Ty, RegSize), "new_reg_offs");
4474   CGF.Builder.CreateStore(NewOffset, reg_offs_p);
4475 
4476   // Now we're in a position to decide whether this argument really was in
4477   // registers or not.
4478   llvm::Value *InRegs = nullptr;
4479   InRegs = CGF.Builder.CreateICmpSLE(
4480       NewOffset, llvm::ConstantInt::get(CGF.Int32Ty, 0), "inreg");
4481 
4482   CGF.Builder.CreateCondBr(InRegs, InRegBlock, OnStackBlock);
4483 
4484   //=======================================
4485   // Argument was in registers
4486   //=======================================
4487 
4488   // Now we emit the code for if the argument was originally passed in
4489   // registers. First start the appropriate block:
4490   CGF.EmitBlock(InRegBlock);
4491 
4492   llvm::Value *reg_top = nullptr;
4493   Address reg_top_p = CGF.Builder.CreateStructGEP(VAListAddr, reg_top_index,
4494                                                   reg_top_offset, "reg_top_p");
4495   reg_top = CGF.Builder.CreateLoad(reg_top_p, "reg_top");
4496   Address BaseAddr(CGF.Builder.CreateInBoundsGEP(reg_top, reg_offs),
4497                    CharUnits::fromQuantity(IsFPR ? 16 : 8));
4498   Address RegAddr = Address::invalid();
4499   llvm::Type *MemTy = CGF.ConvertTypeForMem(Ty);
4500 
4501   if (IsIndirect) {
4502     // If it's been passed indirectly (actually a struct), whatever we find from
4503     // stored registers or on the stack will actually be a struct **.
4504     MemTy = llvm::PointerType::getUnqual(MemTy);
4505   }
4506 
4507   const Type *Base = nullptr;
4508   uint64_t NumMembers = 0;
4509   bool IsHFA = isHomogeneousAggregate(Ty, Base, NumMembers);
4510   if (IsHFA && NumMembers > 1) {
4511     // Homogeneous aggregates passed in registers will have their elements split
4512     // and stored 16-bytes apart regardless of size (they're notionally in qN,
4513     // qN+1, ...). We reload and store into a temporary local variable
4514     // contiguously.
4515     assert(!IsIndirect && "Homogeneous aggregates should be passed directly");
4516     auto BaseTyInfo = getContext().getTypeInfoInChars(QualType(Base, 0));
4517     llvm::Type *BaseTy = CGF.ConvertType(QualType(Base, 0));
4518     llvm::Type *HFATy = llvm::ArrayType::get(BaseTy, NumMembers);
4519     Address Tmp = CGF.CreateTempAlloca(HFATy,
4520                                        std::max(TyAlign, BaseTyInfo.second));
4521 
4522     // On big-endian platforms, the value will be right-aligned in its slot.
4523     int Offset = 0;
4524     if (CGF.CGM.getDataLayout().isBigEndian() &&
4525         BaseTyInfo.first.getQuantity() < 16)
4526       Offset = 16 - BaseTyInfo.first.getQuantity();
4527 
4528     for (unsigned i = 0; i < NumMembers; ++i) {
4529       CharUnits BaseOffset = CharUnits::fromQuantity(16 * i + Offset);
4530       Address LoadAddr =
4531         CGF.Builder.CreateConstInBoundsByteGEP(BaseAddr, BaseOffset);
4532       LoadAddr = CGF.Builder.CreateElementBitCast(LoadAddr, BaseTy);
4533 
4534       Address StoreAddr =
4535         CGF.Builder.CreateConstArrayGEP(Tmp, i, BaseTyInfo.first);
4536 
4537       llvm::Value *Elem = CGF.Builder.CreateLoad(LoadAddr);
4538       CGF.Builder.CreateStore(Elem, StoreAddr);
4539     }
4540 
4541     RegAddr = CGF.Builder.CreateElementBitCast(Tmp, MemTy);
4542   } else {
4543     // Otherwise the object is contiguous in memory.
4544 
4545     // It might be right-aligned in its slot.
4546     CharUnits SlotSize = BaseAddr.getAlignment();
4547     if (CGF.CGM.getDataLayout().isBigEndian() && !IsIndirect &&
4548         (IsHFA || !isAggregateTypeForABI(Ty)) &&
4549         TyInfo.first < SlotSize) {
4550       CharUnits Offset = SlotSize - TyInfo.first;
4551       BaseAddr = CGF.Builder.CreateConstInBoundsByteGEP(BaseAddr, Offset);
4552     }
4553 
4554     RegAddr = CGF.Builder.CreateElementBitCast(BaseAddr, MemTy);
4555   }
4556 
4557   CGF.EmitBranch(ContBlock);
4558 
4559   //=======================================
4560   // Argument was on the stack
4561   //=======================================
4562   CGF.EmitBlock(OnStackBlock);
4563 
4564   Address stack_p = CGF.Builder.CreateStructGEP(VAListAddr, 0,
4565                                                 CharUnits::Zero(), "stack_p");
4566   llvm::Value *OnStackPtr = CGF.Builder.CreateLoad(stack_p, "stack");
4567 
4568   // Again, stack arguments may need realignment. In this case both integer and
4569   // floating-point ones might be affected.
4570   if (!IsIndirect && TyAlign.getQuantity() > 8) {
4571     int Align = TyAlign.getQuantity();
4572 
4573     OnStackPtr = CGF.Builder.CreatePtrToInt(OnStackPtr, CGF.Int64Ty);
4574 
4575     OnStackPtr = CGF.Builder.CreateAdd(
4576         OnStackPtr, llvm::ConstantInt::get(CGF.Int64Ty, Align - 1),
4577         "align_stack");
4578     OnStackPtr = CGF.Builder.CreateAnd(
4579         OnStackPtr, llvm::ConstantInt::get(CGF.Int64Ty, -Align),
4580         "align_stack");
4581 
4582     OnStackPtr = CGF.Builder.CreateIntToPtr(OnStackPtr, CGF.Int8PtrTy);
4583   }
4584   Address OnStackAddr(OnStackPtr,
4585                       std::max(CharUnits::fromQuantity(8), TyAlign));
4586 
4587   // All stack slots are multiples of 8 bytes.
4588   CharUnits StackSlotSize = CharUnits::fromQuantity(8);
4589   CharUnits StackSize;
4590   if (IsIndirect)
4591     StackSize = StackSlotSize;
4592   else
4593     StackSize = TyInfo.first.RoundUpToAlignment(StackSlotSize);
4594 
4595   llvm::Value *StackSizeC = CGF.Builder.getSize(StackSize);
4596   llvm::Value *NewStack =
4597       CGF.Builder.CreateInBoundsGEP(OnStackPtr, StackSizeC, "new_stack");
4598 
4599   // Write the new value of __stack for the next call to va_arg
4600   CGF.Builder.CreateStore(NewStack, stack_p);
4601 
4602   if (CGF.CGM.getDataLayout().isBigEndian() && !isAggregateTypeForABI(Ty) &&
4603       TyInfo.first < StackSlotSize) {
4604     CharUnits Offset = StackSlotSize - TyInfo.first;
4605     OnStackAddr = CGF.Builder.CreateConstInBoundsByteGEP(OnStackAddr, Offset);
4606   }
4607 
4608   OnStackAddr = CGF.Builder.CreateElementBitCast(OnStackAddr, MemTy);
4609 
4610   CGF.EmitBranch(ContBlock);
4611 
4612   //=======================================
4613   // Tidy up
4614   //=======================================
4615   CGF.EmitBlock(ContBlock);
4616 
4617   Address ResAddr = emitMergePHI(CGF, RegAddr, InRegBlock,
4618                                  OnStackAddr, OnStackBlock, "vaargs.addr");
4619 
4620   if (IsIndirect)
4621     return Address(CGF.Builder.CreateLoad(ResAddr, "vaarg.addr"),
4622                    TyInfo.second);
4623 
4624   return ResAddr;
4625 }
4626 
4627 Address AArch64ABIInfo::EmitDarwinVAArg(Address VAListAddr, QualType Ty,
4628                                         CodeGenFunction &CGF) const {
4629   // The backend's lowering doesn't support va_arg for aggregates or
4630   // illegal vector types.  Lower VAArg here for these cases and use
4631   // the LLVM va_arg instruction for everything else.
4632   if (!isAggregateTypeForABI(Ty) && !isIllegalVectorType(Ty))
4633     return Address::invalid();
4634 
4635   CharUnits SlotSize = CharUnits::fromQuantity(8);
4636 
4637   // Empty records are ignored for parameter passing purposes.
4638   if (isEmptyRecord(getContext(), Ty, true)) {
4639     Address Addr(CGF.Builder.CreateLoad(VAListAddr, "ap.cur"), SlotSize);
4640     Addr = CGF.Builder.CreateElementBitCast(Addr, CGF.ConvertTypeForMem(Ty));
4641     return Addr;
4642   }
4643 
4644   // The size of the actual thing passed, which might end up just
4645   // being a pointer for indirect types.
4646   auto TyInfo = getContext().getTypeInfoInChars(Ty);
4647 
4648   // Arguments bigger than 16 bytes which aren't homogeneous
4649   // aggregates should be passed indirectly.
4650   bool IsIndirect = false;
4651   if (TyInfo.first.getQuantity() > 16) {
4652     const Type *Base = nullptr;
4653     uint64_t Members = 0;
4654     IsIndirect = !isHomogeneousAggregate(Ty, Base, Members);
4655   }
4656 
4657   return emitVoidPtrVAArg(CGF, VAListAddr, Ty, IsIndirect,
4658                           TyInfo, SlotSize, /*AllowHigherAlign*/ true);
4659 }
4660 
4661 //===----------------------------------------------------------------------===//
4662 // ARM ABI Implementation
4663 //===----------------------------------------------------------------------===//
4664 
4665 namespace {
4666 
4667 class ARMABIInfo : public ABIInfo {
4668 public:
4669   enum ABIKind {
4670     APCS = 0,
4671     AAPCS = 1,
4672     AAPCS_VFP
4673   };
4674 
4675 private:
4676   ABIKind Kind;
4677 
4678 public:
4679   ARMABIInfo(CodeGenTypes &CGT, ABIKind _Kind) : ABIInfo(CGT), Kind(_Kind) {
4680     setCCs();
4681   }
4682 
4683   bool isEABI() const {
4684     switch (getTarget().getTriple().getEnvironment()) {
4685     case llvm::Triple::Android:
4686     case llvm::Triple::EABI:
4687     case llvm::Triple::EABIHF:
4688     case llvm::Triple::GNUEABI:
4689     case llvm::Triple::GNUEABIHF:
4690       return true;
4691     default:
4692       return false;
4693     }
4694   }
4695 
4696   bool isEABIHF() const {
4697     switch (getTarget().getTriple().getEnvironment()) {
4698     case llvm::Triple::EABIHF:
4699     case llvm::Triple::GNUEABIHF:
4700       return true;
4701     default:
4702       return false;
4703     }
4704   }
4705 
4706   ABIKind getABIKind() const { return Kind; }
4707 
4708 private:
4709   ABIArgInfo classifyReturnType(QualType RetTy, bool isVariadic) const;
4710   ABIArgInfo classifyArgumentType(QualType RetTy, bool isVariadic) const;
4711   bool isIllegalVectorType(QualType Ty) const;
4712 
4713   bool isHomogeneousAggregateBaseType(QualType Ty) const override;
4714   bool isHomogeneousAggregateSmallEnough(const Type *Ty,
4715                                          uint64_t Members) const override;
4716 
4717   void computeInfo(CGFunctionInfo &FI) const override;
4718 
4719   Address EmitVAArg(CodeGenFunction &CGF, Address VAListAddr,
4720                     QualType Ty) const override;
4721 
4722   llvm::CallingConv::ID getLLVMDefaultCC() const;
4723   llvm::CallingConv::ID getABIDefaultCC() const;
4724   void setCCs();
4725 };
4726 
4727 class ARMTargetCodeGenInfo : public TargetCodeGenInfo {
4728 public:
4729   ARMTargetCodeGenInfo(CodeGenTypes &CGT, ARMABIInfo::ABIKind K)
4730     :TargetCodeGenInfo(new ARMABIInfo(CGT, K)) {}
4731 
4732   const ARMABIInfo &getABIInfo() const {
4733     return static_cast<const ARMABIInfo&>(TargetCodeGenInfo::getABIInfo());
4734   }
4735 
4736   int getDwarfEHStackPointer(CodeGen::CodeGenModule &M) const override {
4737     return 13;
4738   }
4739 
4740   StringRef getARCRetainAutoreleasedReturnValueMarker() const override {
4741     return "mov\tr7, r7\t\t@ marker for objc_retainAutoreleaseReturnValue";
4742   }
4743 
4744   bool initDwarfEHRegSizeTable(CodeGen::CodeGenFunction &CGF,
4745                                llvm::Value *Address) const override {
4746     llvm::Value *Four8 = llvm::ConstantInt::get(CGF.Int8Ty, 4);
4747 
4748     // 0-15 are the 16 integer registers.
4749     AssignToArrayRange(CGF.Builder, Address, Four8, 0, 15);
4750     return false;
4751   }
4752 
4753   unsigned getSizeOfUnwindException() const override {
4754     if (getABIInfo().isEABI()) return 88;
4755     return TargetCodeGenInfo::getSizeOfUnwindException();
4756   }
4757 
4758   void setTargetAttributes(const Decl *D, llvm::GlobalValue *GV,
4759                            CodeGen::CodeGenModule &CGM) const override {
4760     const FunctionDecl *FD = dyn_cast_or_null<FunctionDecl>(D);
4761     if (!FD)
4762       return;
4763 
4764     const ARMInterruptAttr *Attr = FD->getAttr<ARMInterruptAttr>();
4765     if (!Attr)
4766       return;
4767 
4768     const char *Kind;
4769     switch (Attr->getInterrupt()) {
4770     case ARMInterruptAttr::Generic: Kind = ""; break;
4771     case ARMInterruptAttr::IRQ:     Kind = "IRQ"; break;
4772     case ARMInterruptAttr::FIQ:     Kind = "FIQ"; break;
4773     case ARMInterruptAttr::SWI:     Kind = "SWI"; break;
4774     case ARMInterruptAttr::ABORT:   Kind = "ABORT"; break;
4775     case ARMInterruptAttr::UNDEF:   Kind = "UNDEF"; break;
4776     }
4777 
4778     llvm::Function *Fn = cast<llvm::Function>(GV);
4779 
4780     Fn->addFnAttr("interrupt", Kind);
4781 
4782     if (cast<ARMABIInfo>(getABIInfo()).getABIKind() == ARMABIInfo::APCS)
4783       return;
4784 
4785     // AAPCS guarantees that sp will be 8-byte aligned on any public interface,
4786     // however this is not necessarily true on taking any interrupt. Instruct
4787     // the backend to perform a realignment as part of the function prologue.
4788     llvm::AttrBuilder B;
4789     B.addStackAlignmentAttr(8);
4790     Fn->addAttributes(llvm::AttributeSet::FunctionIndex,
4791                       llvm::AttributeSet::get(CGM.getLLVMContext(),
4792                                               llvm::AttributeSet::FunctionIndex,
4793                                               B));
4794   }
4795 };
4796 
4797 class WindowsARMTargetCodeGenInfo : public ARMTargetCodeGenInfo {
4798   void addStackProbeSizeTargetAttribute(const Decl *D, llvm::GlobalValue *GV,
4799                                         CodeGen::CodeGenModule &CGM) const;
4800 
4801 public:
4802   WindowsARMTargetCodeGenInfo(CodeGenTypes &CGT, ARMABIInfo::ABIKind K)
4803       : ARMTargetCodeGenInfo(CGT, K) {}
4804 
4805   void setTargetAttributes(const Decl *D, llvm::GlobalValue *GV,
4806                            CodeGen::CodeGenModule &CGM) const override;
4807 };
4808 
4809 void WindowsARMTargetCodeGenInfo::addStackProbeSizeTargetAttribute(
4810     const Decl *D, llvm::GlobalValue *GV, CodeGen::CodeGenModule &CGM) const {
4811   if (!isa<FunctionDecl>(D))
4812     return;
4813   if (CGM.getCodeGenOpts().StackProbeSize == 4096)
4814     return;
4815 
4816   llvm::Function *F = cast<llvm::Function>(GV);
4817   F->addFnAttr("stack-probe-size",
4818                llvm::utostr(CGM.getCodeGenOpts().StackProbeSize));
4819 }
4820 
4821 void WindowsARMTargetCodeGenInfo::setTargetAttributes(
4822     const Decl *D, llvm::GlobalValue *GV, CodeGen::CodeGenModule &CGM) const {
4823   ARMTargetCodeGenInfo::setTargetAttributes(D, GV, CGM);
4824   addStackProbeSizeTargetAttribute(D, GV, CGM);
4825 }
4826 }
4827 
4828 void ARMABIInfo::computeInfo(CGFunctionInfo &FI) const {
4829   if (!getCXXABI().classifyReturnType(FI))
4830     FI.getReturnInfo() =
4831         classifyReturnType(FI.getReturnType(), FI.isVariadic());
4832 
4833   for (auto &I : FI.arguments())
4834     I.info = classifyArgumentType(I.type, FI.isVariadic());
4835 
4836   // Always honor user-specified calling convention.
4837   if (FI.getCallingConvention() != llvm::CallingConv::C)
4838     return;
4839 
4840   llvm::CallingConv::ID cc = getRuntimeCC();
4841   if (cc != llvm::CallingConv::C)
4842     FI.setEffectiveCallingConvention(cc);
4843 }
4844 
4845 /// Return the default calling convention that LLVM will use.
4846 llvm::CallingConv::ID ARMABIInfo::getLLVMDefaultCC() const {
4847   // The default calling convention that LLVM will infer.
4848   if (isEABIHF())
4849     return llvm::CallingConv::ARM_AAPCS_VFP;
4850   else if (isEABI())
4851     return llvm::CallingConv::ARM_AAPCS;
4852   else
4853     return llvm::CallingConv::ARM_APCS;
4854 }
4855 
4856 /// Return the calling convention that our ABI would like us to use
4857 /// as the C calling convention.
4858 llvm::CallingConv::ID ARMABIInfo::getABIDefaultCC() const {
4859   switch (getABIKind()) {
4860   case APCS: return llvm::CallingConv::ARM_APCS;
4861   case AAPCS: return llvm::CallingConv::ARM_AAPCS;
4862   case AAPCS_VFP: return llvm::CallingConv::ARM_AAPCS_VFP;
4863   }
4864   llvm_unreachable("bad ABI kind");
4865 }
4866 
4867 void ARMABIInfo::setCCs() {
4868   assert(getRuntimeCC() == llvm::CallingConv::C);
4869 
4870   // Don't muddy up the IR with a ton of explicit annotations if
4871   // they'd just match what LLVM will infer from the triple.
4872   llvm::CallingConv::ID abiCC = getABIDefaultCC();
4873   if (abiCC != getLLVMDefaultCC())
4874     RuntimeCC = abiCC;
4875 
4876   BuiltinCC = (getABIKind() == APCS ?
4877                llvm::CallingConv::ARM_APCS : llvm::CallingConv::ARM_AAPCS);
4878 }
4879 
4880 ABIArgInfo ARMABIInfo::classifyArgumentType(QualType Ty,
4881                                             bool isVariadic) const {
4882   // 6.1.2.1 The following argument types are VFP CPRCs:
4883   //   A single-precision floating-point type (including promoted
4884   //   half-precision types); A double-precision floating-point type;
4885   //   A 64-bit or 128-bit containerized vector type; Homogeneous Aggregate
4886   //   with a Base Type of a single- or double-precision floating-point type,
4887   //   64-bit containerized vectors or 128-bit containerized vectors with one
4888   //   to four Elements.
4889   bool IsEffectivelyAAPCS_VFP = getABIKind() == AAPCS_VFP && !isVariadic;
4890 
4891   Ty = useFirstFieldIfTransparentUnion(Ty);
4892 
4893   // Handle illegal vector types here.
4894   if (isIllegalVectorType(Ty)) {
4895     uint64_t Size = getContext().getTypeSize(Ty);
4896     if (Size <= 32) {
4897       llvm::Type *ResType =
4898           llvm::Type::getInt32Ty(getVMContext());
4899       return ABIArgInfo::getDirect(ResType);
4900     }
4901     if (Size == 64) {
4902       llvm::Type *ResType = llvm::VectorType::get(
4903           llvm::Type::getInt32Ty(getVMContext()), 2);
4904       return ABIArgInfo::getDirect(ResType);
4905     }
4906     if (Size == 128) {
4907       llvm::Type *ResType = llvm::VectorType::get(
4908           llvm::Type::getInt32Ty(getVMContext()), 4);
4909       return ABIArgInfo::getDirect(ResType);
4910     }
4911     return getNaturalAlignIndirect(Ty, /*ByVal=*/false);
4912   }
4913 
4914   // __fp16 gets passed as if it were an int or float, but with the top 16 bits
4915   // unspecified. This is not done for OpenCL as it handles the half type
4916   // natively, and does not need to interwork with AAPCS code.
4917   if (Ty->isHalfType() && !getContext().getLangOpts().OpenCL) {
4918     llvm::Type *ResType = IsEffectivelyAAPCS_VFP ?
4919       llvm::Type::getFloatTy(getVMContext()) :
4920       llvm::Type::getInt32Ty(getVMContext());
4921     return ABIArgInfo::getDirect(ResType);
4922   }
4923 
4924   if (!isAggregateTypeForABI(Ty)) {
4925     // Treat an enum type as its underlying type.
4926     if (const EnumType *EnumTy = Ty->getAs<EnumType>()) {
4927       Ty = EnumTy->getDecl()->getIntegerType();
4928     }
4929 
4930     return (Ty->isPromotableIntegerType() ? ABIArgInfo::getExtend()
4931                                           : ABIArgInfo::getDirect());
4932   }
4933 
4934   if (CGCXXABI::RecordArgABI RAA = getRecordArgABI(Ty, getCXXABI())) {
4935     return getNaturalAlignIndirect(Ty, RAA == CGCXXABI::RAA_DirectInMemory);
4936   }
4937 
4938   // Ignore empty records.
4939   if (isEmptyRecord(getContext(), Ty, true))
4940     return ABIArgInfo::getIgnore();
4941 
4942   if (IsEffectivelyAAPCS_VFP) {
4943     // Homogeneous Aggregates need to be expanded when we can fit the aggregate
4944     // into VFP registers.
4945     const Type *Base = nullptr;
4946     uint64_t Members = 0;
4947     if (isHomogeneousAggregate(Ty, Base, Members)) {
4948       assert(Base && "Base class should be set for homogeneous aggregate");
4949       // Base can be a floating-point or a vector.
4950       return ABIArgInfo::getDirect(nullptr, 0, nullptr, false);
4951     }
4952   }
4953 
4954   // Support byval for ARM.
4955   // The ABI alignment for APCS is 4-byte and for AAPCS at least 4-byte and at
4956   // most 8-byte. We realign the indirect argument if type alignment is bigger
4957   // than ABI alignment.
4958   uint64_t ABIAlign = 4;
4959   uint64_t TyAlign = getContext().getTypeAlign(Ty) / 8;
4960   if (getABIKind() == ARMABIInfo::AAPCS_VFP ||
4961        getABIKind() == ARMABIInfo::AAPCS)
4962     ABIAlign = std::min(std::max(TyAlign, (uint64_t)4), (uint64_t)8);
4963 
4964   if (getContext().getTypeSizeInChars(Ty) > CharUnits::fromQuantity(64)) {
4965     return ABIArgInfo::getIndirect(CharUnits::fromQuantity(ABIAlign),
4966                                    /*ByVal=*/true,
4967                                    /*Realign=*/TyAlign > ABIAlign);
4968   }
4969 
4970   // Otherwise, pass by coercing to a structure of the appropriate size.
4971   llvm::Type* ElemTy;
4972   unsigned SizeRegs;
4973   // FIXME: Try to match the types of the arguments more accurately where
4974   // we can.
4975   if (getContext().getTypeAlign(Ty) <= 32) {
4976     ElemTy = llvm::Type::getInt32Ty(getVMContext());
4977     SizeRegs = (getContext().getTypeSize(Ty) + 31) / 32;
4978   } else {
4979     ElemTy = llvm::Type::getInt64Ty(getVMContext());
4980     SizeRegs = (getContext().getTypeSize(Ty) + 63) / 64;
4981   }
4982 
4983   return ABIArgInfo::getDirect(llvm::ArrayType::get(ElemTy, SizeRegs));
4984 }
4985 
4986 static bool isIntegerLikeType(QualType Ty, ASTContext &Context,
4987                               llvm::LLVMContext &VMContext) {
4988   // APCS, C Language Calling Conventions, Non-Simple Return Values: A structure
4989   // is called integer-like if its size is less than or equal to one word, and
4990   // the offset of each of its addressable sub-fields is zero.
4991 
4992   uint64_t Size = Context.getTypeSize(Ty);
4993 
4994   // Check that the type fits in a word.
4995   if (Size > 32)
4996     return false;
4997 
4998   // FIXME: Handle vector types!
4999   if (Ty->isVectorType())
5000     return false;
5001 
5002   // Float types are never treated as "integer like".
5003   if (Ty->isRealFloatingType())
5004     return false;
5005 
5006   // If this is a builtin or pointer type then it is ok.
5007   if (Ty->getAs<BuiltinType>() || Ty->isPointerType())
5008     return true;
5009 
5010   // Small complex integer types are "integer like".
5011   if (const ComplexType *CT = Ty->getAs<ComplexType>())
5012     return isIntegerLikeType(CT->getElementType(), Context, VMContext);
5013 
5014   // Single element and zero sized arrays should be allowed, by the definition
5015   // above, but they are not.
5016 
5017   // Otherwise, it must be a record type.
5018   const RecordType *RT = Ty->getAs<RecordType>();
5019   if (!RT) return false;
5020 
5021   // Ignore records with flexible arrays.
5022   const RecordDecl *RD = RT->getDecl();
5023   if (RD->hasFlexibleArrayMember())
5024     return false;
5025 
5026   // Check that all sub-fields are at offset 0, and are themselves "integer
5027   // like".
5028   const ASTRecordLayout &Layout = Context.getASTRecordLayout(RD);
5029 
5030   bool HadField = false;
5031   unsigned idx = 0;
5032   for (RecordDecl::field_iterator i = RD->field_begin(), e = RD->field_end();
5033        i != e; ++i, ++idx) {
5034     const FieldDecl *FD = *i;
5035 
5036     // Bit-fields are not addressable, we only need to verify they are "integer
5037     // like". We still have to disallow a subsequent non-bitfield, for example:
5038     //   struct { int : 0; int x }
5039     // is non-integer like according to gcc.
5040     if (FD->isBitField()) {
5041       if (!RD->isUnion())
5042         HadField = true;
5043 
5044       if (!isIntegerLikeType(FD->getType(), Context, VMContext))
5045         return false;
5046 
5047       continue;
5048     }
5049 
5050     // Check if this field is at offset 0.
5051     if (Layout.getFieldOffset(idx) != 0)
5052       return false;
5053 
5054     if (!isIntegerLikeType(FD->getType(), Context, VMContext))
5055       return false;
5056 
5057     // Only allow at most one field in a structure. This doesn't match the
5058     // wording above, but follows gcc in situations with a field following an
5059     // empty structure.
5060     if (!RD->isUnion()) {
5061       if (HadField)
5062         return false;
5063 
5064       HadField = true;
5065     }
5066   }
5067 
5068   return true;
5069 }
5070 
5071 ABIArgInfo ARMABIInfo::classifyReturnType(QualType RetTy,
5072                                           bool isVariadic) const {
5073   bool IsEffectivelyAAPCS_VFP = getABIKind() == AAPCS_VFP && !isVariadic;
5074 
5075   if (RetTy->isVoidType())
5076     return ABIArgInfo::getIgnore();
5077 
5078   // Large vector types should be returned via memory.
5079   if (RetTy->isVectorType() && getContext().getTypeSize(RetTy) > 128) {
5080     return getNaturalAlignIndirect(RetTy);
5081   }
5082 
5083   // __fp16 gets returned as if it were an int or float, but with the top 16
5084   // bits unspecified. This is not done for OpenCL as it handles the half type
5085   // natively, and does not need to interwork with AAPCS code.
5086   if (RetTy->isHalfType() && !getContext().getLangOpts().OpenCL) {
5087     llvm::Type *ResType = IsEffectivelyAAPCS_VFP ?
5088       llvm::Type::getFloatTy(getVMContext()) :
5089       llvm::Type::getInt32Ty(getVMContext());
5090     return ABIArgInfo::getDirect(ResType);
5091   }
5092 
5093   if (!isAggregateTypeForABI(RetTy)) {
5094     // Treat an enum type as its underlying type.
5095     if (const EnumType *EnumTy = RetTy->getAs<EnumType>())
5096       RetTy = EnumTy->getDecl()->getIntegerType();
5097 
5098     return RetTy->isPromotableIntegerType() ? ABIArgInfo::getExtend()
5099                                             : ABIArgInfo::getDirect();
5100   }
5101 
5102   // Are we following APCS?
5103   if (getABIKind() == APCS) {
5104     if (isEmptyRecord(getContext(), RetTy, false))
5105       return ABIArgInfo::getIgnore();
5106 
5107     // Complex types are all returned as packed integers.
5108     //
5109     // FIXME: Consider using 2 x vector types if the back end handles them
5110     // correctly.
5111     if (RetTy->isAnyComplexType())
5112       return ABIArgInfo::getDirect(llvm::IntegerType::get(
5113           getVMContext(), getContext().getTypeSize(RetTy)));
5114 
5115     // Integer like structures are returned in r0.
5116     if (isIntegerLikeType(RetTy, getContext(), getVMContext())) {
5117       // Return in the smallest viable integer type.
5118       uint64_t Size = getContext().getTypeSize(RetTy);
5119       if (Size <= 8)
5120         return ABIArgInfo::getDirect(llvm::Type::getInt8Ty(getVMContext()));
5121       if (Size <= 16)
5122         return ABIArgInfo::getDirect(llvm::Type::getInt16Ty(getVMContext()));
5123       return ABIArgInfo::getDirect(llvm::Type::getInt32Ty(getVMContext()));
5124     }
5125 
5126     // Otherwise return in memory.
5127     return getNaturalAlignIndirect(RetTy);
5128   }
5129 
5130   // Otherwise this is an AAPCS variant.
5131 
5132   if (isEmptyRecord(getContext(), RetTy, true))
5133     return ABIArgInfo::getIgnore();
5134 
5135   // Check for homogeneous aggregates with AAPCS-VFP.
5136   if (IsEffectivelyAAPCS_VFP) {
5137     const Type *Base = nullptr;
5138     uint64_t Members;
5139     if (isHomogeneousAggregate(RetTy, Base, Members)) {
5140       assert(Base && "Base class should be set for homogeneous aggregate");
5141       // Homogeneous Aggregates are returned directly.
5142       return ABIArgInfo::getDirect(nullptr, 0, nullptr, false);
5143     }
5144   }
5145 
5146   // Aggregates <= 4 bytes are returned in r0; other aggregates
5147   // are returned indirectly.
5148   uint64_t Size = getContext().getTypeSize(RetTy);
5149   if (Size <= 32) {
5150     if (getDataLayout().isBigEndian())
5151       // Return in 32 bit integer integer type (as if loaded by LDR, AAPCS 5.4)
5152       return ABIArgInfo::getDirect(llvm::Type::getInt32Ty(getVMContext()));
5153 
5154     // Return in the smallest viable integer type.
5155     if (Size <= 8)
5156       return ABIArgInfo::getDirect(llvm::Type::getInt8Ty(getVMContext()));
5157     if (Size <= 16)
5158       return ABIArgInfo::getDirect(llvm::Type::getInt16Ty(getVMContext()));
5159     return ABIArgInfo::getDirect(llvm::Type::getInt32Ty(getVMContext()));
5160   }
5161 
5162   return getNaturalAlignIndirect(RetTy);
5163 }
5164 
5165 /// isIllegalVector - check whether Ty is an illegal vector type.
5166 bool ARMABIInfo::isIllegalVectorType(QualType Ty) const {
5167   if (const VectorType *VT = Ty->getAs<VectorType>()) {
5168     // Check whether VT is legal.
5169     unsigned NumElements = VT->getNumElements();
5170     uint64_t Size = getContext().getTypeSize(VT);
5171     // NumElements should be power of 2.
5172     if ((NumElements & (NumElements - 1)) != 0)
5173       return true;
5174     // Size should be greater than 32 bits.
5175     return Size <= 32;
5176   }
5177   return false;
5178 }
5179 
5180 bool ARMABIInfo::isHomogeneousAggregateBaseType(QualType Ty) const {
5181   // Homogeneous aggregates for AAPCS-VFP must have base types of float,
5182   // double, or 64-bit or 128-bit vectors.
5183   if (const BuiltinType *BT = Ty->getAs<BuiltinType>()) {
5184     if (BT->getKind() == BuiltinType::Float ||
5185         BT->getKind() == BuiltinType::Double ||
5186         BT->getKind() == BuiltinType::LongDouble)
5187       return true;
5188   } else if (const VectorType *VT = Ty->getAs<VectorType>()) {
5189     unsigned VecSize = getContext().getTypeSize(VT);
5190     if (VecSize == 64 || VecSize == 128)
5191       return true;
5192   }
5193   return false;
5194 }
5195 
5196 bool ARMABIInfo::isHomogeneousAggregateSmallEnough(const Type *Base,
5197                                                    uint64_t Members) const {
5198   return Members <= 4;
5199 }
5200 
5201 Address ARMABIInfo::EmitVAArg(CodeGenFunction &CGF, Address VAListAddr,
5202                               QualType Ty) const {
5203   CharUnits SlotSize = CharUnits::fromQuantity(4);
5204 
5205   // Empty records are ignored for parameter passing purposes.
5206   if (isEmptyRecord(getContext(), Ty, true)) {
5207     Address Addr(CGF.Builder.CreateLoad(VAListAddr), SlotSize);
5208     Addr = CGF.Builder.CreateElementBitCast(Addr, CGF.ConvertTypeForMem(Ty));
5209     return Addr;
5210   }
5211 
5212   auto TyInfo = getContext().getTypeInfoInChars(Ty);
5213   CharUnits TyAlignForABI = TyInfo.second;
5214 
5215   // Use indirect if size of the illegal vector is bigger than 16 bytes.
5216   bool IsIndirect = false;
5217   if (TyInfo.first > CharUnits::fromQuantity(16) && isIllegalVectorType(Ty)) {
5218     IsIndirect = true;
5219 
5220   // Otherwise, bound the type's ABI alignment.
5221   // The ABI alignment for 64-bit or 128-bit vectors is 8 for AAPCS and 4 for
5222   // APCS. For AAPCS, the ABI alignment is at least 4-byte and at most 8-byte.
5223   // Our callers should be prepared to handle an under-aligned address.
5224   } else if (getABIKind() == ARMABIInfo::AAPCS_VFP ||
5225              getABIKind() == ARMABIInfo::AAPCS) {
5226     TyAlignForABI = std::max(TyAlignForABI, CharUnits::fromQuantity(4));
5227     TyAlignForABI = std::min(TyAlignForABI, CharUnits::fromQuantity(8));
5228   } else {
5229     TyAlignForABI = CharUnits::fromQuantity(4);
5230   }
5231   TyInfo.second = TyAlignForABI;
5232 
5233   return emitVoidPtrVAArg(CGF, VAListAddr, Ty, IsIndirect, TyInfo,
5234                           SlotSize, /*AllowHigherAlign*/ true);
5235 }
5236 
5237 //===----------------------------------------------------------------------===//
5238 // NVPTX ABI Implementation
5239 //===----------------------------------------------------------------------===//
5240 
5241 namespace {
5242 
5243 class NVPTXABIInfo : public ABIInfo {
5244 public:
5245   NVPTXABIInfo(CodeGenTypes &CGT) : ABIInfo(CGT) {}
5246 
5247   ABIArgInfo classifyReturnType(QualType RetTy) const;
5248   ABIArgInfo classifyArgumentType(QualType Ty) const;
5249 
5250   void computeInfo(CGFunctionInfo &FI) const override;
5251   Address EmitVAArg(CodeGenFunction &CGF, Address VAListAddr,
5252                     QualType Ty) const override;
5253 };
5254 
5255 class NVPTXTargetCodeGenInfo : public TargetCodeGenInfo {
5256 public:
5257   NVPTXTargetCodeGenInfo(CodeGenTypes &CGT)
5258     : TargetCodeGenInfo(new NVPTXABIInfo(CGT)) {}
5259 
5260   void setTargetAttributes(const Decl *D, llvm::GlobalValue *GV,
5261                            CodeGen::CodeGenModule &M) const override;
5262 private:
5263   // Adds a NamedMDNode with F, Name, and Operand as operands, and adds the
5264   // resulting MDNode to the nvvm.annotations MDNode.
5265   static void addNVVMMetadata(llvm::Function *F, StringRef Name, int Operand);
5266 };
5267 
5268 ABIArgInfo NVPTXABIInfo::classifyReturnType(QualType RetTy) const {
5269   if (RetTy->isVoidType())
5270     return ABIArgInfo::getIgnore();
5271 
5272   // note: this is different from default ABI
5273   if (!RetTy->isScalarType())
5274     return ABIArgInfo::getDirect();
5275 
5276   // Treat an enum type as its underlying type.
5277   if (const EnumType *EnumTy = RetTy->getAs<EnumType>())
5278     RetTy = EnumTy->getDecl()->getIntegerType();
5279 
5280   return (RetTy->isPromotableIntegerType() ?
5281           ABIArgInfo::getExtend() : ABIArgInfo::getDirect());
5282 }
5283 
5284 ABIArgInfo NVPTXABIInfo::classifyArgumentType(QualType Ty) const {
5285   // Treat an enum type as its underlying type.
5286   if (const EnumType *EnumTy = Ty->getAs<EnumType>())
5287     Ty = EnumTy->getDecl()->getIntegerType();
5288 
5289   // Return aggregates type as indirect by value
5290   if (isAggregateTypeForABI(Ty))
5291     return getNaturalAlignIndirect(Ty, /* byval */ true);
5292 
5293   return (Ty->isPromotableIntegerType() ?
5294           ABIArgInfo::getExtend() : ABIArgInfo::getDirect());
5295 }
5296 
5297 void NVPTXABIInfo::computeInfo(CGFunctionInfo &FI) const {
5298   if (!getCXXABI().classifyReturnType(FI))
5299     FI.getReturnInfo() = classifyReturnType(FI.getReturnType());
5300   for (auto &I : FI.arguments())
5301     I.info = classifyArgumentType(I.type);
5302 
5303   // Always honor user-specified calling convention.
5304   if (FI.getCallingConvention() != llvm::CallingConv::C)
5305     return;
5306 
5307   FI.setEffectiveCallingConvention(getRuntimeCC());
5308 }
5309 
5310 Address NVPTXABIInfo::EmitVAArg(CodeGenFunction &CGF, Address VAListAddr,
5311                                 QualType Ty) const {
5312   llvm_unreachable("NVPTX does not support varargs");
5313 }
5314 
5315 void NVPTXTargetCodeGenInfo::
5316 setTargetAttributes(const Decl *D, llvm::GlobalValue *GV,
5317                     CodeGen::CodeGenModule &M) const{
5318   const FunctionDecl *FD = dyn_cast_or_null<FunctionDecl>(D);
5319   if (!FD) return;
5320 
5321   llvm::Function *F = cast<llvm::Function>(GV);
5322 
5323   // Perform special handling in OpenCL mode
5324   if (M.getLangOpts().OpenCL) {
5325     // Use OpenCL function attributes to check for kernel functions
5326     // By default, all functions are device functions
5327     if (FD->hasAttr<OpenCLKernelAttr>()) {
5328       // OpenCL __kernel functions get kernel metadata
5329       // Create !{<func-ref>, metadata !"kernel", i32 1} node
5330       addNVVMMetadata(F, "kernel", 1);
5331       // And kernel functions are not subject to inlining
5332       F->addFnAttr(llvm::Attribute::NoInline);
5333     }
5334   }
5335 
5336   // Perform special handling in CUDA mode.
5337   if (M.getLangOpts().CUDA) {
5338     // CUDA __global__ functions get a kernel metadata entry.  Since
5339     // __global__ functions cannot be called from the device, we do not
5340     // need to set the noinline attribute.
5341     if (FD->hasAttr<CUDAGlobalAttr>()) {
5342       // Create !{<func-ref>, metadata !"kernel", i32 1} node
5343       addNVVMMetadata(F, "kernel", 1);
5344     }
5345     if (CUDALaunchBoundsAttr *Attr = FD->getAttr<CUDALaunchBoundsAttr>()) {
5346       // Create !{<func-ref>, metadata !"maxntidx", i32 <val>} node
5347       llvm::APSInt MaxThreads(32);
5348       MaxThreads = Attr->getMaxThreads()->EvaluateKnownConstInt(M.getContext());
5349       if (MaxThreads > 0)
5350         addNVVMMetadata(F, "maxntidx", MaxThreads.getExtValue());
5351 
5352       // min blocks is an optional argument for CUDALaunchBoundsAttr. If it was
5353       // not specified in __launch_bounds__ or if the user specified a 0 value,
5354       // we don't have to add a PTX directive.
5355       if (Attr->getMinBlocks()) {
5356         llvm::APSInt MinBlocks(32);
5357         MinBlocks = Attr->getMinBlocks()->EvaluateKnownConstInt(M.getContext());
5358         if (MinBlocks > 0)
5359           // Create !{<func-ref>, metadata !"minctasm", i32 <val>} node
5360           addNVVMMetadata(F, "minctasm", MinBlocks.getExtValue());
5361       }
5362     }
5363   }
5364 }
5365 
5366 void NVPTXTargetCodeGenInfo::addNVVMMetadata(llvm::Function *F, StringRef Name,
5367                                              int Operand) {
5368   llvm::Module *M = F->getParent();
5369   llvm::LLVMContext &Ctx = M->getContext();
5370 
5371   // Get "nvvm.annotations" metadata node
5372   llvm::NamedMDNode *MD = M->getOrInsertNamedMetadata("nvvm.annotations");
5373 
5374   llvm::Metadata *MDVals[] = {
5375       llvm::ConstantAsMetadata::get(F), llvm::MDString::get(Ctx, Name),
5376       llvm::ConstantAsMetadata::get(
5377           llvm::ConstantInt::get(llvm::Type::getInt32Ty(Ctx), Operand))};
5378   // Append metadata to nvvm.annotations
5379   MD->addOperand(llvm::MDNode::get(Ctx, MDVals));
5380 }
5381 }
5382 
5383 //===----------------------------------------------------------------------===//
5384 // SystemZ ABI Implementation
5385 //===----------------------------------------------------------------------===//
5386 
5387 namespace {
5388 
5389 class SystemZABIInfo : public ABIInfo {
5390   bool HasVector;
5391 
5392 public:
5393   SystemZABIInfo(CodeGenTypes &CGT, bool HV)
5394     : ABIInfo(CGT), HasVector(HV) {}
5395 
5396   bool isPromotableIntegerType(QualType Ty) const;
5397   bool isCompoundType(QualType Ty) const;
5398   bool isVectorArgumentType(QualType Ty) const;
5399   bool isFPArgumentType(QualType Ty) const;
5400   QualType GetSingleElementType(QualType Ty) const;
5401 
5402   ABIArgInfo classifyReturnType(QualType RetTy) const;
5403   ABIArgInfo classifyArgumentType(QualType ArgTy) const;
5404 
5405   void computeInfo(CGFunctionInfo &FI) const override {
5406     if (!getCXXABI().classifyReturnType(FI))
5407       FI.getReturnInfo() = classifyReturnType(FI.getReturnType());
5408     for (auto &I : FI.arguments())
5409       I.info = classifyArgumentType(I.type);
5410   }
5411 
5412   Address EmitVAArg(CodeGenFunction &CGF, Address VAListAddr,
5413                     QualType Ty) const override;
5414 };
5415 
5416 class SystemZTargetCodeGenInfo : public TargetCodeGenInfo {
5417 public:
5418   SystemZTargetCodeGenInfo(CodeGenTypes &CGT, bool HasVector)
5419     : TargetCodeGenInfo(new SystemZABIInfo(CGT, HasVector)) {}
5420 };
5421 
5422 }
5423 
5424 bool SystemZABIInfo::isPromotableIntegerType(QualType Ty) const {
5425   // Treat an enum type as its underlying type.
5426   if (const EnumType *EnumTy = Ty->getAs<EnumType>())
5427     Ty = EnumTy->getDecl()->getIntegerType();
5428 
5429   // Promotable integer types are required to be promoted by the ABI.
5430   if (Ty->isPromotableIntegerType())
5431     return true;
5432 
5433   // 32-bit values must also be promoted.
5434   if (const BuiltinType *BT = Ty->getAs<BuiltinType>())
5435     switch (BT->getKind()) {
5436     case BuiltinType::Int:
5437     case BuiltinType::UInt:
5438       return true;
5439     default:
5440       return false;
5441     }
5442   return false;
5443 }
5444 
5445 bool SystemZABIInfo::isCompoundType(QualType Ty) const {
5446   return (Ty->isAnyComplexType() ||
5447           Ty->isVectorType() ||
5448           isAggregateTypeForABI(Ty));
5449 }
5450 
5451 bool SystemZABIInfo::isVectorArgumentType(QualType Ty) const {
5452   return (HasVector &&
5453           Ty->isVectorType() &&
5454           getContext().getTypeSize(Ty) <= 128);
5455 }
5456 
5457 bool SystemZABIInfo::isFPArgumentType(QualType Ty) const {
5458   if (const BuiltinType *BT = Ty->getAs<BuiltinType>())
5459     switch (BT->getKind()) {
5460     case BuiltinType::Float:
5461     case BuiltinType::Double:
5462       return true;
5463     default:
5464       return false;
5465     }
5466 
5467   return false;
5468 }
5469 
5470 QualType SystemZABIInfo::GetSingleElementType(QualType Ty) const {
5471   if (const RecordType *RT = Ty->getAsStructureType()) {
5472     const RecordDecl *RD = RT->getDecl();
5473     QualType Found;
5474 
5475     // If this is a C++ record, check the bases first.
5476     if (const CXXRecordDecl *CXXRD = dyn_cast<CXXRecordDecl>(RD))
5477       for (const auto &I : CXXRD->bases()) {
5478         QualType Base = I.getType();
5479 
5480         // Empty bases don't affect things either way.
5481         if (isEmptyRecord(getContext(), Base, true))
5482           continue;
5483 
5484         if (!Found.isNull())
5485           return Ty;
5486         Found = GetSingleElementType(Base);
5487       }
5488 
5489     // Check the fields.
5490     for (const auto *FD : RD->fields()) {
5491       // For compatibility with GCC, ignore empty bitfields in C++ mode.
5492       // Unlike isSingleElementStruct(), empty structure and array fields
5493       // do count.  So do anonymous bitfields that aren't zero-sized.
5494       if (getContext().getLangOpts().CPlusPlus &&
5495           FD->isBitField() && FD->getBitWidthValue(getContext()) == 0)
5496         continue;
5497 
5498       // Unlike isSingleElementStruct(), arrays do not count.
5499       // Nested structures still do though.
5500       if (!Found.isNull())
5501         return Ty;
5502       Found = GetSingleElementType(FD->getType());
5503     }
5504 
5505     // Unlike isSingleElementStruct(), trailing padding is allowed.
5506     // An 8-byte aligned struct s { float f; } is passed as a double.
5507     if (!Found.isNull())
5508       return Found;
5509   }
5510 
5511   return Ty;
5512 }
5513 
5514 Address SystemZABIInfo::EmitVAArg(CodeGenFunction &CGF, Address VAListAddr,
5515                                   QualType Ty) const {
5516   // Assume that va_list type is correct; should be pointer to LLVM type:
5517   // struct {
5518   //   i64 __gpr;
5519   //   i64 __fpr;
5520   //   i8 *__overflow_arg_area;
5521   //   i8 *__reg_save_area;
5522   // };
5523 
5524   // Every non-vector argument occupies 8 bytes and is passed by preference
5525   // in either GPRs or FPRs.  Vector arguments occupy 8 or 16 bytes and are
5526   // always passed on the stack.
5527   Ty = getContext().getCanonicalType(Ty);
5528   auto TyInfo = getContext().getTypeInfoInChars(Ty);
5529   llvm::Type *ArgTy = CGF.ConvertTypeForMem(Ty);
5530   llvm::Type *DirectTy = ArgTy;
5531   ABIArgInfo AI = classifyArgumentType(Ty);
5532   bool IsIndirect = AI.isIndirect();
5533   bool InFPRs = false;
5534   bool IsVector = false;
5535   CharUnits UnpaddedSize;
5536   CharUnits DirectAlign;
5537   if (IsIndirect) {
5538     DirectTy = llvm::PointerType::getUnqual(DirectTy);
5539     UnpaddedSize = DirectAlign = CharUnits::fromQuantity(8);
5540   } else {
5541     if (AI.getCoerceToType())
5542       ArgTy = AI.getCoerceToType();
5543     InFPRs = ArgTy->isFloatTy() || ArgTy->isDoubleTy();
5544     IsVector = ArgTy->isVectorTy();
5545     UnpaddedSize = TyInfo.first;
5546     DirectAlign = TyInfo.second;
5547   }
5548   CharUnits PaddedSize = CharUnits::fromQuantity(8);
5549   if (IsVector && UnpaddedSize > PaddedSize)
5550     PaddedSize = CharUnits::fromQuantity(16);
5551   assert((UnpaddedSize <= PaddedSize) && "Invalid argument size.");
5552 
5553   CharUnits Padding = (PaddedSize - UnpaddedSize);
5554 
5555   llvm::Type *IndexTy = CGF.Int64Ty;
5556   llvm::Value *PaddedSizeV =
5557     llvm::ConstantInt::get(IndexTy, PaddedSize.getQuantity());
5558 
5559   if (IsVector) {
5560     // Work out the address of a vector argument on the stack.
5561     // Vector arguments are always passed in the high bits of a
5562     // single (8 byte) or double (16 byte) stack slot.
5563     Address OverflowArgAreaPtr =
5564       CGF.Builder.CreateStructGEP(VAListAddr, 2, CharUnits::fromQuantity(16),
5565                                   "overflow_arg_area_ptr");
5566     Address OverflowArgArea =
5567       Address(CGF.Builder.CreateLoad(OverflowArgAreaPtr, "overflow_arg_area"),
5568               TyInfo.second);
5569     Address MemAddr =
5570       CGF.Builder.CreateElementBitCast(OverflowArgArea, DirectTy, "mem_addr");
5571 
5572     // Update overflow_arg_area_ptr pointer
5573     llvm::Value *NewOverflowArgArea =
5574       CGF.Builder.CreateGEP(OverflowArgArea.getPointer(), PaddedSizeV,
5575                             "overflow_arg_area");
5576     CGF.Builder.CreateStore(NewOverflowArgArea, OverflowArgAreaPtr);
5577 
5578     return MemAddr;
5579   }
5580 
5581   assert(PaddedSize.getQuantity() == 8);
5582 
5583   unsigned MaxRegs, RegCountField, RegSaveIndex;
5584   CharUnits RegPadding;
5585   if (InFPRs) {
5586     MaxRegs = 4; // Maximum of 4 FPR arguments
5587     RegCountField = 1; // __fpr
5588     RegSaveIndex = 16; // save offset for f0
5589     RegPadding = CharUnits(); // floats are passed in the high bits of an FPR
5590   } else {
5591     MaxRegs = 5; // Maximum of 5 GPR arguments
5592     RegCountField = 0; // __gpr
5593     RegSaveIndex = 2; // save offset for r2
5594     RegPadding = Padding; // values are passed in the low bits of a GPR
5595   }
5596 
5597   Address RegCountPtr = CGF.Builder.CreateStructGEP(
5598       VAListAddr, RegCountField, RegCountField * CharUnits::fromQuantity(8),
5599       "reg_count_ptr");
5600   llvm::Value *RegCount = CGF.Builder.CreateLoad(RegCountPtr, "reg_count");
5601   llvm::Value *MaxRegsV = llvm::ConstantInt::get(IndexTy, MaxRegs);
5602   llvm::Value *InRegs = CGF.Builder.CreateICmpULT(RegCount, MaxRegsV,
5603                                                  "fits_in_regs");
5604 
5605   llvm::BasicBlock *InRegBlock = CGF.createBasicBlock("vaarg.in_reg");
5606   llvm::BasicBlock *InMemBlock = CGF.createBasicBlock("vaarg.in_mem");
5607   llvm::BasicBlock *ContBlock = CGF.createBasicBlock("vaarg.end");
5608   CGF.Builder.CreateCondBr(InRegs, InRegBlock, InMemBlock);
5609 
5610   // Emit code to load the value if it was passed in registers.
5611   CGF.EmitBlock(InRegBlock);
5612 
5613   // Work out the address of an argument register.
5614   llvm::Value *ScaledRegCount =
5615     CGF.Builder.CreateMul(RegCount, PaddedSizeV, "scaled_reg_count");
5616   llvm::Value *RegBase =
5617     llvm::ConstantInt::get(IndexTy, RegSaveIndex * PaddedSize.getQuantity()
5618                                       + RegPadding.getQuantity());
5619   llvm::Value *RegOffset =
5620     CGF.Builder.CreateAdd(ScaledRegCount, RegBase, "reg_offset");
5621   Address RegSaveAreaPtr =
5622       CGF.Builder.CreateStructGEP(VAListAddr, 3, CharUnits::fromQuantity(24),
5623                                   "reg_save_area_ptr");
5624   llvm::Value *RegSaveArea =
5625     CGF.Builder.CreateLoad(RegSaveAreaPtr, "reg_save_area");
5626   Address RawRegAddr(CGF.Builder.CreateGEP(RegSaveArea, RegOffset,
5627                                            "raw_reg_addr"),
5628                      PaddedSize);
5629   Address RegAddr =
5630     CGF.Builder.CreateElementBitCast(RawRegAddr, DirectTy, "reg_addr");
5631 
5632   // Update the register count
5633   llvm::Value *One = llvm::ConstantInt::get(IndexTy, 1);
5634   llvm::Value *NewRegCount =
5635     CGF.Builder.CreateAdd(RegCount, One, "reg_count");
5636   CGF.Builder.CreateStore(NewRegCount, RegCountPtr);
5637   CGF.EmitBranch(ContBlock);
5638 
5639   // Emit code to load the value if it was passed in memory.
5640   CGF.EmitBlock(InMemBlock);
5641 
5642   // Work out the address of a stack argument.
5643   Address OverflowArgAreaPtr = CGF.Builder.CreateStructGEP(
5644       VAListAddr, 2, CharUnits::fromQuantity(16), "overflow_arg_area_ptr");
5645   Address OverflowArgArea =
5646     Address(CGF.Builder.CreateLoad(OverflowArgAreaPtr, "overflow_arg_area"),
5647             PaddedSize);
5648   Address RawMemAddr =
5649     CGF.Builder.CreateConstByteGEP(OverflowArgArea, Padding, "raw_mem_addr");
5650   Address MemAddr =
5651     CGF.Builder.CreateElementBitCast(RawMemAddr, DirectTy, "mem_addr");
5652 
5653   // Update overflow_arg_area_ptr pointer
5654   llvm::Value *NewOverflowArgArea =
5655     CGF.Builder.CreateGEP(OverflowArgArea.getPointer(), PaddedSizeV,
5656                           "overflow_arg_area");
5657   CGF.Builder.CreateStore(NewOverflowArgArea, OverflowArgAreaPtr);
5658   CGF.EmitBranch(ContBlock);
5659 
5660   // Return the appropriate result.
5661   CGF.EmitBlock(ContBlock);
5662   Address ResAddr = emitMergePHI(CGF, RegAddr, InRegBlock,
5663                                  MemAddr, InMemBlock, "va_arg.addr");
5664 
5665   if (IsIndirect)
5666     ResAddr = Address(CGF.Builder.CreateLoad(ResAddr, "indirect_arg"),
5667                       TyInfo.second);
5668 
5669   return ResAddr;
5670 }
5671 
5672 ABIArgInfo SystemZABIInfo::classifyReturnType(QualType RetTy) const {
5673   if (RetTy->isVoidType())
5674     return ABIArgInfo::getIgnore();
5675   if (isVectorArgumentType(RetTy))
5676     return ABIArgInfo::getDirect();
5677   if (isCompoundType(RetTy) || getContext().getTypeSize(RetTy) > 64)
5678     return getNaturalAlignIndirect(RetTy);
5679   return (isPromotableIntegerType(RetTy) ?
5680           ABIArgInfo::getExtend() : ABIArgInfo::getDirect());
5681 }
5682 
5683 ABIArgInfo SystemZABIInfo::classifyArgumentType(QualType Ty) const {
5684   // Handle the generic C++ ABI.
5685   if (CGCXXABI::RecordArgABI RAA = getRecordArgABI(Ty, getCXXABI()))
5686     return getNaturalAlignIndirect(Ty, RAA == CGCXXABI::RAA_DirectInMemory);
5687 
5688   // Integers and enums are extended to full register width.
5689   if (isPromotableIntegerType(Ty))
5690     return ABIArgInfo::getExtend();
5691 
5692   // Handle vector types and vector-like structure types.  Note that
5693   // as opposed to float-like structure types, we do not allow any
5694   // padding for vector-like structures, so verify the sizes match.
5695   uint64_t Size = getContext().getTypeSize(Ty);
5696   QualType SingleElementTy = GetSingleElementType(Ty);
5697   if (isVectorArgumentType(SingleElementTy) &&
5698       getContext().getTypeSize(SingleElementTy) == Size)
5699     return ABIArgInfo::getDirect(CGT.ConvertType(SingleElementTy));
5700 
5701   // Values that are not 1, 2, 4 or 8 bytes in size are passed indirectly.
5702   if (Size != 8 && Size != 16 && Size != 32 && Size != 64)
5703     return getNaturalAlignIndirect(Ty, /*ByVal=*/false);
5704 
5705   // Handle small structures.
5706   if (const RecordType *RT = Ty->getAs<RecordType>()) {
5707     // Structures with flexible arrays have variable length, so really
5708     // fail the size test above.
5709     const RecordDecl *RD = RT->getDecl();
5710     if (RD->hasFlexibleArrayMember())
5711       return getNaturalAlignIndirect(Ty, /*ByVal=*/false);
5712 
5713     // The structure is passed as an unextended integer, a float, or a double.
5714     llvm::Type *PassTy;
5715     if (isFPArgumentType(SingleElementTy)) {
5716       assert(Size == 32 || Size == 64);
5717       if (Size == 32)
5718         PassTy = llvm::Type::getFloatTy(getVMContext());
5719       else
5720         PassTy = llvm::Type::getDoubleTy(getVMContext());
5721     } else
5722       PassTy = llvm::IntegerType::get(getVMContext(), Size);
5723     return ABIArgInfo::getDirect(PassTy);
5724   }
5725 
5726   // Non-structure compounds are passed indirectly.
5727   if (isCompoundType(Ty))
5728     return getNaturalAlignIndirect(Ty, /*ByVal=*/false);
5729 
5730   return ABIArgInfo::getDirect(nullptr);
5731 }
5732 
5733 //===----------------------------------------------------------------------===//
5734 // MSP430 ABI Implementation
5735 //===----------------------------------------------------------------------===//
5736 
5737 namespace {
5738 
5739 class MSP430TargetCodeGenInfo : public TargetCodeGenInfo {
5740 public:
5741   MSP430TargetCodeGenInfo(CodeGenTypes &CGT)
5742     : TargetCodeGenInfo(new DefaultABIInfo(CGT)) {}
5743   void setTargetAttributes(const Decl *D, llvm::GlobalValue *GV,
5744                            CodeGen::CodeGenModule &M) const override;
5745 };
5746 
5747 }
5748 
5749 void MSP430TargetCodeGenInfo::setTargetAttributes(const Decl *D,
5750                                                   llvm::GlobalValue *GV,
5751                                              CodeGen::CodeGenModule &M) const {
5752   if (const FunctionDecl *FD = dyn_cast_or_null<FunctionDecl>(D)) {
5753     if (const MSP430InterruptAttr *attr = FD->getAttr<MSP430InterruptAttr>()) {
5754       // Handle 'interrupt' attribute:
5755       llvm::Function *F = cast<llvm::Function>(GV);
5756 
5757       // Step 1: Set ISR calling convention.
5758       F->setCallingConv(llvm::CallingConv::MSP430_INTR);
5759 
5760       // Step 2: Add attributes goodness.
5761       F->addFnAttr(llvm::Attribute::NoInline);
5762 
5763       // Step 3: Emit ISR vector alias.
5764       unsigned Num = attr->getNumber() / 2;
5765       llvm::GlobalAlias::create(llvm::Function::ExternalLinkage,
5766                                 "__isr_" + Twine(Num), F);
5767     }
5768   }
5769 }
5770 
5771 //===----------------------------------------------------------------------===//
5772 // MIPS ABI Implementation.  This works for both little-endian and
5773 // big-endian variants.
5774 //===----------------------------------------------------------------------===//
5775 
5776 namespace {
5777 class MipsABIInfo : public ABIInfo {
5778   bool IsO32;
5779   unsigned MinABIStackAlignInBytes, StackAlignInBytes;
5780   void CoerceToIntArgs(uint64_t TySize,
5781                        SmallVectorImpl<llvm::Type *> &ArgList) const;
5782   llvm::Type* HandleAggregates(QualType Ty, uint64_t TySize) const;
5783   llvm::Type* returnAggregateInRegs(QualType RetTy, uint64_t Size) const;
5784   llvm::Type* getPaddingType(uint64_t Align, uint64_t Offset) const;
5785 public:
5786   MipsABIInfo(CodeGenTypes &CGT, bool _IsO32) :
5787     ABIInfo(CGT), IsO32(_IsO32), MinABIStackAlignInBytes(IsO32 ? 4 : 8),
5788     StackAlignInBytes(IsO32 ? 8 : 16) {}
5789 
5790   ABIArgInfo classifyReturnType(QualType RetTy) const;
5791   ABIArgInfo classifyArgumentType(QualType RetTy, uint64_t &Offset) const;
5792   void computeInfo(CGFunctionInfo &FI) const override;
5793   Address EmitVAArg(CodeGenFunction &CGF, Address VAListAddr,
5794                     QualType Ty) const override;
5795   bool shouldSignExtUnsignedType(QualType Ty) const override;
5796 };
5797 
5798 class MIPSTargetCodeGenInfo : public TargetCodeGenInfo {
5799   unsigned SizeOfUnwindException;
5800 public:
5801   MIPSTargetCodeGenInfo(CodeGenTypes &CGT, bool IsO32)
5802     : TargetCodeGenInfo(new MipsABIInfo(CGT, IsO32)),
5803       SizeOfUnwindException(IsO32 ? 24 : 32) {}
5804 
5805   int getDwarfEHStackPointer(CodeGen::CodeGenModule &CGM) const override {
5806     return 29;
5807   }
5808 
5809   void setTargetAttributes(const Decl *D, llvm::GlobalValue *GV,
5810                            CodeGen::CodeGenModule &CGM) const override {
5811     const FunctionDecl *FD = dyn_cast_or_null<FunctionDecl>(D);
5812     if (!FD) return;
5813     llvm::Function *Fn = cast<llvm::Function>(GV);
5814     if (FD->hasAttr<Mips16Attr>()) {
5815       Fn->addFnAttr("mips16");
5816     }
5817     else if (FD->hasAttr<NoMips16Attr>()) {
5818       Fn->addFnAttr("nomips16");
5819     }
5820   }
5821 
5822   bool initDwarfEHRegSizeTable(CodeGen::CodeGenFunction &CGF,
5823                                llvm::Value *Address) const override;
5824 
5825   unsigned getSizeOfUnwindException() const override {
5826     return SizeOfUnwindException;
5827   }
5828 };
5829 }
5830 
5831 void MipsABIInfo::CoerceToIntArgs(
5832     uint64_t TySize, SmallVectorImpl<llvm::Type *> &ArgList) const {
5833   llvm::IntegerType *IntTy =
5834     llvm::IntegerType::get(getVMContext(), MinABIStackAlignInBytes * 8);
5835 
5836   // Add (TySize / MinABIStackAlignInBytes) args of IntTy.
5837   for (unsigned N = TySize / (MinABIStackAlignInBytes * 8); N; --N)
5838     ArgList.push_back(IntTy);
5839 
5840   // If necessary, add one more integer type to ArgList.
5841   unsigned R = TySize % (MinABIStackAlignInBytes * 8);
5842 
5843   if (R)
5844     ArgList.push_back(llvm::IntegerType::get(getVMContext(), R));
5845 }
5846 
5847 // In N32/64, an aligned double precision floating point field is passed in
5848 // a register.
5849 llvm::Type* MipsABIInfo::HandleAggregates(QualType Ty, uint64_t TySize) const {
5850   SmallVector<llvm::Type*, 8> ArgList, IntArgList;
5851 
5852   if (IsO32) {
5853     CoerceToIntArgs(TySize, ArgList);
5854     return llvm::StructType::get(getVMContext(), ArgList);
5855   }
5856 
5857   if (Ty->isComplexType())
5858     return CGT.ConvertType(Ty);
5859 
5860   const RecordType *RT = Ty->getAs<RecordType>();
5861 
5862   // Unions/vectors are passed in integer registers.
5863   if (!RT || !RT->isStructureOrClassType()) {
5864     CoerceToIntArgs(TySize, ArgList);
5865     return llvm::StructType::get(getVMContext(), ArgList);
5866   }
5867 
5868   const RecordDecl *RD = RT->getDecl();
5869   const ASTRecordLayout &Layout = getContext().getASTRecordLayout(RD);
5870   assert(!(TySize % 8) && "Size of structure must be multiple of 8.");
5871 
5872   uint64_t LastOffset = 0;
5873   unsigned idx = 0;
5874   llvm::IntegerType *I64 = llvm::IntegerType::get(getVMContext(), 64);
5875 
5876   // Iterate over fields in the struct/class and check if there are any aligned
5877   // double fields.
5878   for (RecordDecl::field_iterator i = RD->field_begin(), e = RD->field_end();
5879        i != e; ++i, ++idx) {
5880     const QualType Ty = i->getType();
5881     const BuiltinType *BT = Ty->getAs<BuiltinType>();
5882 
5883     if (!BT || BT->getKind() != BuiltinType::Double)
5884       continue;
5885 
5886     uint64_t Offset = Layout.getFieldOffset(idx);
5887     if (Offset % 64) // Ignore doubles that are not aligned.
5888       continue;
5889 
5890     // Add ((Offset - LastOffset) / 64) args of type i64.
5891     for (unsigned j = (Offset - LastOffset) / 64; j > 0; --j)
5892       ArgList.push_back(I64);
5893 
5894     // Add double type.
5895     ArgList.push_back(llvm::Type::getDoubleTy(getVMContext()));
5896     LastOffset = Offset + 64;
5897   }
5898 
5899   CoerceToIntArgs(TySize - LastOffset, IntArgList);
5900   ArgList.append(IntArgList.begin(), IntArgList.end());
5901 
5902   return llvm::StructType::get(getVMContext(), ArgList);
5903 }
5904 
5905 llvm::Type *MipsABIInfo::getPaddingType(uint64_t OrigOffset,
5906                                         uint64_t Offset) const {
5907   if (OrigOffset + MinABIStackAlignInBytes > Offset)
5908     return nullptr;
5909 
5910   return llvm::IntegerType::get(getVMContext(), (Offset - OrigOffset) * 8);
5911 }
5912 
5913 ABIArgInfo
5914 MipsABIInfo::classifyArgumentType(QualType Ty, uint64_t &Offset) const {
5915   Ty = useFirstFieldIfTransparentUnion(Ty);
5916 
5917   uint64_t OrigOffset = Offset;
5918   uint64_t TySize = getContext().getTypeSize(Ty);
5919   uint64_t Align = getContext().getTypeAlign(Ty) / 8;
5920 
5921   Align = std::min(std::max(Align, (uint64_t)MinABIStackAlignInBytes),
5922                    (uint64_t)StackAlignInBytes);
5923   unsigned CurrOffset = llvm::RoundUpToAlignment(Offset, Align);
5924   Offset = CurrOffset + llvm::RoundUpToAlignment(TySize, Align * 8) / 8;
5925 
5926   if (isAggregateTypeForABI(Ty) || Ty->isVectorType()) {
5927     // Ignore empty aggregates.
5928     if (TySize == 0)
5929       return ABIArgInfo::getIgnore();
5930 
5931     if (CGCXXABI::RecordArgABI RAA = getRecordArgABI(Ty, getCXXABI())) {
5932       Offset = OrigOffset + MinABIStackAlignInBytes;
5933       return getNaturalAlignIndirect(Ty, RAA == CGCXXABI::RAA_DirectInMemory);
5934     }
5935 
5936     // If we have reached here, aggregates are passed directly by coercing to
5937     // another structure type. Padding is inserted if the offset of the
5938     // aggregate is unaligned.
5939     ABIArgInfo ArgInfo =
5940         ABIArgInfo::getDirect(HandleAggregates(Ty, TySize), 0,
5941                               getPaddingType(OrigOffset, CurrOffset));
5942     ArgInfo.setInReg(true);
5943     return ArgInfo;
5944   }
5945 
5946   // Treat an enum type as its underlying type.
5947   if (const EnumType *EnumTy = Ty->getAs<EnumType>())
5948     Ty = EnumTy->getDecl()->getIntegerType();
5949 
5950   // All integral types are promoted to the GPR width.
5951   if (Ty->isIntegralOrEnumerationType())
5952     return ABIArgInfo::getExtend();
5953 
5954   return ABIArgInfo::getDirect(
5955       nullptr, 0, IsO32 ? nullptr : getPaddingType(OrigOffset, CurrOffset));
5956 }
5957 
5958 llvm::Type*
5959 MipsABIInfo::returnAggregateInRegs(QualType RetTy, uint64_t Size) const {
5960   const RecordType *RT = RetTy->getAs<RecordType>();
5961   SmallVector<llvm::Type*, 8> RTList;
5962 
5963   if (RT && RT->isStructureOrClassType()) {
5964     const RecordDecl *RD = RT->getDecl();
5965     const ASTRecordLayout &Layout = getContext().getASTRecordLayout(RD);
5966     unsigned FieldCnt = Layout.getFieldCount();
5967 
5968     // N32/64 returns struct/classes in floating point registers if the
5969     // following conditions are met:
5970     // 1. The size of the struct/class is no larger than 128-bit.
5971     // 2. The struct/class has one or two fields all of which are floating
5972     //    point types.
5973     // 3. The offset of the first field is zero (this follows what gcc does).
5974     //
5975     // Any other composite results are returned in integer registers.
5976     //
5977     if (FieldCnt && (FieldCnt <= 2) && !Layout.getFieldOffset(0)) {
5978       RecordDecl::field_iterator b = RD->field_begin(), e = RD->field_end();
5979       for (; b != e; ++b) {
5980         const BuiltinType *BT = b->getType()->getAs<BuiltinType>();
5981 
5982         if (!BT || !BT->isFloatingPoint())
5983           break;
5984 
5985         RTList.push_back(CGT.ConvertType(b->getType()));
5986       }
5987 
5988       if (b == e)
5989         return llvm::StructType::get(getVMContext(), RTList,
5990                                      RD->hasAttr<PackedAttr>());
5991 
5992       RTList.clear();
5993     }
5994   }
5995 
5996   CoerceToIntArgs(Size, RTList);
5997   return llvm::StructType::get(getVMContext(), RTList);
5998 }
5999 
6000 ABIArgInfo MipsABIInfo::classifyReturnType(QualType RetTy) const {
6001   uint64_t Size = getContext().getTypeSize(RetTy);
6002 
6003   if (RetTy->isVoidType())
6004     return ABIArgInfo::getIgnore();
6005 
6006   // O32 doesn't treat zero-sized structs differently from other structs.
6007   // However, N32/N64 ignores zero sized return values.
6008   if (!IsO32 && Size == 0)
6009     return ABIArgInfo::getIgnore();
6010 
6011   if (isAggregateTypeForABI(RetTy) || RetTy->isVectorType()) {
6012     if (Size <= 128) {
6013       if (RetTy->isAnyComplexType())
6014         return ABIArgInfo::getDirect();
6015 
6016       // O32 returns integer vectors in registers and N32/N64 returns all small
6017       // aggregates in registers.
6018       if (!IsO32 ||
6019           (RetTy->isVectorType() && !RetTy->hasFloatingRepresentation())) {
6020         ABIArgInfo ArgInfo =
6021             ABIArgInfo::getDirect(returnAggregateInRegs(RetTy, Size));
6022         ArgInfo.setInReg(true);
6023         return ArgInfo;
6024       }
6025     }
6026 
6027     return getNaturalAlignIndirect(RetTy);
6028   }
6029 
6030   // Treat an enum type as its underlying type.
6031   if (const EnumType *EnumTy = RetTy->getAs<EnumType>())
6032     RetTy = EnumTy->getDecl()->getIntegerType();
6033 
6034   return (RetTy->isPromotableIntegerType() ?
6035           ABIArgInfo::getExtend() : ABIArgInfo::getDirect());
6036 }
6037 
6038 void MipsABIInfo::computeInfo(CGFunctionInfo &FI) const {
6039   ABIArgInfo &RetInfo = FI.getReturnInfo();
6040   if (!getCXXABI().classifyReturnType(FI))
6041     RetInfo = classifyReturnType(FI.getReturnType());
6042 
6043   // Check if a pointer to an aggregate is passed as a hidden argument.
6044   uint64_t Offset = RetInfo.isIndirect() ? MinABIStackAlignInBytes : 0;
6045 
6046   for (auto &I : FI.arguments())
6047     I.info = classifyArgumentType(I.type, Offset);
6048 }
6049 
6050 Address MipsABIInfo::EmitVAArg(CodeGenFunction &CGF, Address VAListAddr,
6051                                QualType OrigTy) const {
6052   QualType Ty = OrigTy;
6053 
6054   // Integer arguments are promoted to 32-bit on O32 and 64-bit on N32/N64.
6055   // Pointers are also promoted in the same way but this only matters for N32.
6056   unsigned SlotSizeInBits = IsO32 ? 32 : 64;
6057   unsigned PtrWidth = getTarget().getPointerWidth(0);
6058   bool DidPromote = false;
6059   if ((Ty->isIntegerType() &&
6060           getContext().getIntWidth(Ty) < SlotSizeInBits) ||
6061       (Ty->isPointerType() && PtrWidth < SlotSizeInBits)) {
6062     DidPromote = true;
6063     Ty = getContext().getIntTypeForBitwidth(SlotSizeInBits,
6064                                             Ty->isSignedIntegerType());
6065   }
6066 
6067   auto TyInfo = getContext().getTypeInfoInChars(Ty);
6068 
6069   // The alignment of things in the argument area is never larger than
6070   // StackAlignInBytes.
6071   TyInfo.second =
6072     std::min(TyInfo.second, CharUnits::fromQuantity(StackAlignInBytes));
6073 
6074   // MinABIStackAlignInBytes is the size of argument slots on the stack.
6075   CharUnits ArgSlotSize = CharUnits::fromQuantity(MinABIStackAlignInBytes);
6076 
6077   Address Addr = emitVoidPtrVAArg(CGF, VAListAddr, Ty, /*indirect*/ false,
6078                           TyInfo, ArgSlotSize, /*AllowHigherAlign*/ true);
6079 
6080 
6081   // If there was a promotion, "unpromote" into a temporary.
6082   // TODO: can we just use a pointer into a subset of the original slot?
6083   if (DidPromote) {
6084     Address Temp = CGF.CreateMemTemp(OrigTy, "vaarg.promotion-temp");
6085     llvm::Value *Promoted = CGF.Builder.CreateLoad(Addr);
6086 
6087     // Truncate down to the right width.
6088     llvm::Type *IntTy = (OrigTy->isIntegerType() ? Temp.getElementType()
6089                                                  : CGF.IntPtrTy);
6090     llvm::Value *V = CGF.Builder.CreateTrunc(Promoted, IntTy);
6091     if (OrigTy->isPointerType())
6092       V = CGF.Builder.CreateIntToPtr(V, Temp.getElementType());
6093 
6094     CGF.Builder.CreateStore(V, Temp);
6095     Addr = Temp;
6096   }
6097 
6098   return Addr;
6099 }
6100 
6101 bool MipsABIInfo::shouldSignExtUnsignedType(QualType Ty) const {
6102   int TySize = getContext().getTypeSize(Ty);
6103 
6104   // MIPS64 ABI requires unsigned 32 bit integers to be sign extended.
6105   if (Ty->isUnsignedIntegerOrEnumerationType() && TySize == 32)
6106     return true;
6107 
6108   return false;
6109 }
6110 
6111 bool
6112 MIPSTargetCodeGenInfo::initDwarfEHRegSizeTable(CodeGen::CodeGenFunction &CGF,
6113                                                llvm::Value *Address) const {
6114   // This information comes from gcc's implementation, which seems to
6115   // as canonical as it gets.
6116 
6117   // Everything on MIPS is 4 bytes.  Double-precision FP registers
6118   // are aliased to pairs of single-precision FP registers.
6119   llvm::Value *Four8 = llvm::ConstantInt::get(CGF.Int8Ty, 4);
6120 
6121   // 0-31 are the general purpose registers, $0 - $31.
6122   // 32-63 are the floating-point registers, $f0 - $f31.
6123   // 64 and 65 are the multiply/divide registers, $hi and $lo.
6124   // 66 is the (notional, I think) register for signal-handler return.
6125   AssignToArrayRange(CGF.Builder, Address, Four8, 0, 65);
6126 
6127   // 67-74 are the floating-point status registers, $fcc0 - $fcc7.
6128   // They are one bit wide and ignored here.
6129 
6130   // 80-111 are the coprocessor 0 registers, $c0r0 - $c0r31.
6131   // (coprocessor 1 is the FP unit)
6132   // 112-143 are the coprocessor 2 registers, $c2r0 - $c2r31.
6133   // 144-175 are the coprocessor 3 registers, $c3r0 - $c3r31.
6134   // 176-181 are the DSP accumulator registers.
6135   AssignToArrayRange(CGF.Builder, Address, Four8, 80, 181);
6136   return false;
6137 }
6138 
6139 //===----------------------------------------------------------------------===//
6140 // TCE ABI Implementation (see http://tce.cs.tut.fi). Uses mostly the defaults.
6141 // Currently subclassed only to implement custom OpenCL C function attribute
6142 // handling.
6143 //===----------------------------------------------------------------------===//
6144 
6145 namespace {
6146 
6147 class TCETargetCodeGenInfo : public DefaultTargetCodeGenInfo {
6148 public:
6149   TCETargetCodeGenInfo(CodeGenTypes &CGT)
6150     : DefaultTargetCodeGenInfo(CGT) {}
6151 
6152   void setTargetAttributes(const Decl *D, llvm::GlobalValue *GV,
6153                            CodeGen::CodeGenModule &M) const override;
6154 };
6155 
6156 void TCETargetCodeGenInfo::setTargetAttributes(
6157     const Decl *D, llvm::GlobalValue *GV, CodeGen::CodeGenModule &M) const {
6158   const FunctionDecl *FD = dyn_cast_or_null<FunctionDecl>(D);
6159   if (!FD) return;
6160 
6161   llvm::Function *F = cast<llvm::Function>(GV);
6162 
6163   if (M.getLangOpts().OpenCL) {
6164     if (FD->hasAttr<OpenCLKernelAttr>()) {
6165       // OpenCL C Kernel functions are not subject to inlining
6166       F->addFnAttr(llvm::Attribute::NoInline);
6167       const ReqdWorkGroupSizeAttr *Attr = FD->getAttr<ReqdWorkGroupSizeAttr>();
6168       if (Attr) {
6169         // Convert the reqd_work_group_size() attributes to metadata.
6170         llvm::LLVMContext &Context = F->getContext();
6171         llvm::NamedMDNode *OpenCLMetadata =
6172             M.getModule().getOrInsertNamedMetadata(
6173                 "opencl.kernel_wg_size_info");
6174 
6175         SmallVector<llvm::Metadata *, 5> Operands;
6176         Operands.push_back(llvm::ConstantAsMetadata::get(F));
6177 
6178         Operands.push_back(
6179             llvm::ConstantAsMetadata::get(llvm::Constant::getIntegerValue(
6180                 M.Int32Ty, llvm::APInt(32, Attr->getXDim()))));
6181         Operands.push_back(
6182             llvm::ConstantAsMetadata::get(llvm::Constant::getIntegerValue(
6183                 M.Int32Ty, llvm::APInt(32, Attr->getYDim()))));
6184         Operands.push_back(
6185             llvm::ConstantAsMetadata::get(llvm::Constant::getIntegerValue(
6186                 M.Int32Ty, llvm::APInt(32, Attr->getZDim()))));
6187 
6188         // Add a boolean constant operand for "required" (true) or "hint"
6189         // (false) for implementing the work_group_size_hint attr later.
6190         // Currently always true as the hint is not yet implemented.
6191         Operands.push_back(
6192             llvm::ConstantAsMetadata::get(llvm::ConstantInt::getTrue(Context)));
6193         OpenCLMetadata->addOperand(llvm::MDNode::get(Context, Operands));
6194       }
6195     }
6196   }
6197 }
6198 
6199 }
6200 
6201 //===----------------------------------------------------------------------===//
6202 // Hexagon ABI Implementation
6203 //===----------------------------------------------------------------------===//
6204 
6205 namespace {
6206 
6207 class HexagonABIInfo : public ABIInfo {
6208 
6209 
6210 public:
6211   HexagonABIInfo(CodeGenTypes &CGT) : ABIInfo(CGT) {}
6212 
6213 private:
6214 
6215   ABIArgInfo classifyReturnType(QualType RetTy) const;
6216   ABIArgInfo classifyArgumentType(QualType RetTy) const;
6217 
6218   void computeInfo(CGFunctionInfo &FI) const override;
6219 
6220   Address EmitVAArg(CodeGenFunction &CGF, Address VAListAddr,
6221                     QualType Ty) const override;
6222 };
6223 
6224 class HexagonTargetCodeGenInfo : public TargetCodeGenInfo {
6225 public:
6226   HexagonTargetCodeGenInfo(CodeGenTypes &CGT)
6227     :TargetCodeGenInfo(new HexagonABIInfo(CGT)) {}
6228 
6229   int getDwarfEHStackPointer(CodeGen::CodeGenModule &M) const override {
6230     return 29;
6231   }
6232 };
6233 
6234 }
6235 
6236 void HexagonABIInfo::computeInfo(CGFunctionInfo &FI) const {
6237   if (!getCXXABI().classifyReturnType(FI))
6238     FI.getReturnInfo() = classifyReturnType(FI.getReturnType());
6239   for (auto &I : FI.arguments())
6240     I.info = classifyArgumentType(I.type);
6241 }
6242 
6243 ABIArgInfo HexagonABIInfo::classifyArgumentType(QualType Ty) const {
6244   if (!isAggregateTypeForABI(Ty)) {
6245     // Treat an enum type as its underlying type.
6246     if (const EnumType *EnumTy = Ty->getAs<EnumType>())
6247       Ty = EnumTy->getDecl()->getIntegerType();
6248 
6249     return (Ty->isPromotableIntegerType() ?
6250             ABIArgInfo::getExtend() : ABIArgInfo::getDirect());
6251   }
6252 
6253   // Ignore empty records.
6254   if (isEmptyRecord(getContext(), Ty, true))
6255     return ABIArgInfo::getIgnore();
6256 
6257   if (CGCXXABI::RecordArgABI RAA = getRecordArgABI(Ty, getCXXABI()))
6258     return getNaturalAlignIndirect(Ty, RAA == CGCXXABI::RAA_DirectInMemory);
6259 
6260   uint64_t Size = getContext().getTypeSize(Ty);
6261   if (Size > 64)
6262     return getNaturalAlignIndirect(Ty, /*ByVal=*/true);
6263     // Pass in the smallest viable integer type.
6264   else if (Size > 32)
6265       return ABIArgInfo::getDirect(llvm::Type::getInt64Ty(getVMContext()));
6266   else if (Size > 16)
6267       return ABIArgInfo::getDirect(llvm::Type::getInt32Ty(getVMContext()));
6268   else if (Size > 8)
6269       return ABIArgInfo::getDirect(llvm::Type::getInt16Ty(getVMContext()));
6270   else
6271       return ABIArgInfo::getDirect(llvm::Type::getInt8Ty(getVMContext()));
6272 }
6273 
6274 ABIArgInfo HexagonABIInfo::classifyReturnType(QualType RetTy) const {
6275   if (RetTy->isVoidType())
6276     return ABIArgInfo::getIgnore();
6277 
6278   // Large vector types should be returned via memory.
6279   if (RetTy->isVectorType() && getContext().getTypeSize(RetTy) > 64)
6280     return getNaturalAlignIndirect(RetTy);
6281 
6282   if (!isAggregateTypeForABI(RetTy)) {
6283     // Treat an enum type as its underlying type.
6284     if (const EnumType *EnumTy = RetTy->getAs<EnumType>())
6285       RetTy = EnumTy->getDecl()->getIntegerType();
6286 
6287     return (RetTy->isPromotableIntegerType() ?
6288             ABIArgInfo::getExtend() : ABIArgInfo::getDirect());
6289   }
6290 
6291   if (isEmptyRecord(getContext(), RetTy, true))
6292     return ABIArgInfo::getIgnore();
6293 
6294   // Aggregates <= 8 bytes are returned in r0; other aggregates
6295   // are returned indirectly.
6296   uint64_t Size = getContext().getTypeSize(RetTy);
6297   if (Size <= 64) {
6298     // Return in the smallest viable integer type.
6299     if (Size <= 8)
6300       return ABIArgInfo::getDirect(llvm::Type::getInt8Ty(getVMContext()));
6301     if (Size <= 16)
6302       return ABIArgInfo::getDirect(llvm::Type::getInt16Ty(getVMContext()));
6303     if (Size <= 32)
6304       return ABIArgInfo::getDirect(llvm::Type::getInt32Ty(getVMContext()));
6305     return ABIArgInfo::getDirect(llvm::Type::getInt64Ty(getVMContext()));
6306   }
6307 
6308   return getNaturalAlignIndirect(RetTy, /*ByVal=*/true);
6309 }
6310 
6311 Address HexagonABIInfo::EmitVAArg(CodeGenFunction &CGF, Address VAListAddr,
6312                                   QualType Ty) const {
6313   // FIXME: Someone needs to audit that this handle alignment correctly.
6314   return emitVoidPtrVAArg(CGF, VAListAddr, Ty, /*indirect*/ false,
6315                           getContext().getTypeInfoInChars(Ty),
6316                           CharUnits::fromQuantity(4),
6317                           /*AllowHigherAlign*/ true);
6318 }
6319 
6320 //===----------------------------------------------------------------------===//
6321 // AMDGPU ABI Implementation
6322 //===----------------------------------------------------------------------===//
6323 
6324 namespace {
6325 
6326 class AMDGPUTargetCodeGenInfo : public TargetCodeGenInfo {
6327 public:
6328   AMDGPUTargetCodeGenInfo(CodeGenTypes &CGT)
6329     : TargetCodeGenInfo(new DefaultABIInfo(CGT)) {}
6330   void setTargetAttributes(const Decl *D, llvm::GlobalValue *GV,
6331                            CodeGen::CodeGenModule &M) const override;
6332 };
6333 
6334 }
6335 
6336 void AMDGPUTargetCodeGenInfo::setTargetAttributes(
6337   const Decl *D,
6338   llvm::GlobalValue *GV,
6339   CodeGen::CodeGenModule &M) const {
6340   const FunctionDecl *FD = dyn_cast_or_null<FunctionDecl>(D);
6341   if (!FD)
6342     return;
6343 
6344   if (const auto Attr = FD->getAttr<AMDGPUNumVGPRAttr>()) {
6345     llvm::Function *F = cast<llvm::Function>(GV);
6346     uint32_t NumVGPR = Attr->getNumVGPR();
6347     if (NumVGPR != 0)
6348       F->addFnAttr("amdgpu_num_vgpr", llvm::utostr(NumVGPR));
6349   }
6350 
6351   if (const auto Attr = FD->getAttr<AMDGPUNumSGPRAttr>()) {
6352     llvm::Function *F = cast<llvm::Function>(GV);
6353     unsigned NumSGPR = Attr->getNumSGPR();
6354     if (NumSGPR != 0)
6355       F->addFnAttr("amdgpu_num_sgpr", llvm::utostr(NumSGPR));
6356   }
6357 }
6358 
6359 
6360 //===----------------------------------------------------------------------===//
6361 // SPARC v9 ABI Implementation.
6362 // Based on the SPARC Compliance Definition version 2.4.1.
6363 //
6364 // Function arguments a mapped to a nominal "parameter array" and promoted to
6365 // registers depending on their type. Each argument occupies 8 or 16 bytes in
6366 // the array, structs larger than 16 bytes are passed indirectly.
6367 //
6368 // One case requires special care:
6369 //
6370 //   struct mixed {
6371 //     int i;
6372 //     float f;
6373 //   };
6374 //
6375 // When a struct mixed is passed by value, it only occupies 8 bytes in the
6376 // parameter array, but the int is passed in an integer register, and the float
6377 // is passed in a floating point register. This is represented as two arguments
6378 // with the LLVM IR inreg attribute:
6379 //
6380 //   declare void f(i32 inreg %i, float inreg %f)
6381 //
6382 // The code generator will only allocate 4 bytes from the parameter array for
6383 // the inreg arguments. All other arguments are allocated a multiple of 8
6384 // bytes.
6385 //
6386 namespace {
6387 class SparcV9ABIInfo : public ABIInfo {
6388 public:
6389   SparcV9ABIInfo(CodeGenTypes &CGT) : ABIInfo(CGT) {}
6390 
6391 private:
6392   ABIArgInfo classifyType(QualType RetTy, unsigned SizeLimit) const;
6393   void computeInfo(CGFunctionInfo &FI) const override;
6394   Address EmitVAArg(CodeGenFunction &CGF, Address VAListAddr,
6395                     QualType Ty) const override;
6396 
6397   // Coercion type builder for structs passed in registers. The coercion type
6398   // serves two purposes:
6399   //
6400   // 1. Pad structs to a multiple of 64 bits, so they are passed 'left-aligned'
6401   //    in registers.
6402   // 2. Expose aligned floating point elements as first-level elements, so the
6403   //    code generator knows to pass them in floating point registers.
6404   //
6405   // We also compute the InReg flag which indicates that the struct contains
6406   // aligned 32-bit floats.
6407   //
6408   struct CoerceBuilder {
6409     llvm::LLVMContext &Context;
6410     const llvm::DataLayout &DL;
6411     SmallVector<llvm::Type*, 8> Elems;
6412     uint64_t Size;
6413     bool InReg;
6414 
6415     CoerceBuilder(llvm::LLVMContext &c, const llvm::DataLayout &dl)
6416       : Context(c), DL(dl), Size(0), InReg(false) {}
6417 
6418     // Pad Elems with integers until Size is ToSize.
6419     void pad(uint64_t ToSize) {
6420       assert(ToSize >= Size && "Cannot remove elements");
6421       if (ToSize == Size)
6422         return;
6423 
6424       // Finish the current 64-bit word.
6425       uint64_t Aligned = llvm::RoundUpToAlignment(Size, 64);
6426       if (Aligned > Size && Aligned <= ToSize) {
6427         Elems.push_back(llvm::IntegerType::get(Context, Aligned - Size));
6428         Size = Aligned;
6429       }
6430 
6431       // Add whole 64-bit words.
6432       while (Size + 64 <= ToSize) {
6433         Elems.push_back(llvm::Type::getInt64Ty(Context));
6434         Size += 64;
6435       }
6436 
6437       // Final in-word padding.
6438       if (Size < ToSize) {
6439         Elems.push_back(llvm::IntegerType::get(Context, ToSize - Size));
6440         Size = ToSize;
6441       }
6442     }
6443 
6444     // Add a floating point element at Offset.
6445     void addFloat(uint64_t Offset, llvm::Type *Ty, unsigned Bits) {
6446       // Unaligned floats are treated as integers.
6447       if (Offset % Bits)
6448         return;
6449       // The InReg flag is only required if there are any floats < 64 bits.
6450       if (Bits < 64)
6451         InReg = true;
6452       pad(Offset);
6453       Elems.push_back(Ty);
6454       Size = Offset + Bits;
6455     }
6456 
6457     // Add a struct type to the coercion type, starting at Offset (in bits).
6458     void addStruct(uint64_t Offset, llvm::StructType *StrTy) {
6459       const llvm::StructLayout *Layout = DL.getStructLayout(StrTy);
6460       for (unsigned i = 0, e = StrTy->getNumElements(); i != e; ++i) {
6461         llvm::Type *ElemTy = StrTy->getElementType(i);
6462         uint64_t ElemOffset = Offset + Layout->getElementOffsetInBits(i);
6463         switch (ElemTy->getTypeID()) {
6464         case llvm::Type::StructTyID:
6465           addStruct(ElemOffset, cast<llvm::StructType>(ElemTy));
6466           break;
6467         case llvm::Type::FloatTyID:
6468           addFloat(ElemOffset, ElemTy, 32);
6469           break;
6470         case llvm::Type::DoubleTyID:
6471           addFloat(ElemOffset, ElemTy, 64);
6472           break;
6473         case llvm::Type::FP128TyID:
6474           addFloat(ElemOffset, ElemTy, 128);
6475           break;
6476         case llvm::Type::PointerTyID:
6477           if (ElemOffset % 64 == 0) {
6478             pad(ElemOffset);
6479             Elems.push_back(ElemTy);
6480             Size += 64;
6481           }
6482           break;
6483         default:
6484           break;
6485         }
6486       }
6487     }
6488 
6489     // Check if Ty is a usable substitute for the coercion type.
6490     bool isUsableType(llvm::StructType *Ty) const {
6491       return llvm::makeArrayRef(Elems) == Ty->elements();
6492     }
6493 
6494     // Get the coercion type as a literal struct type.
6495     llvm::Type *getType() const {
6496       if (Elems.size() == 1)
6497         return Elems.front();
6498       else
6499         return llvm::StructType::get(Context, Elems);
6500     }
6501   };
6502 };
6503 } // end anonymous namespace
6504 
6505 ABIArgInfo
6506 SparcV9ABIInfo::classifyType(QualType Ty, unsigned SizeLimit) const {
6507   if (Ty->isVoidType())
6508     return ABIArgInfo::getIgnore();
6509 
6510   uint64_t Size = getContext().getTypeSize(Ty);
6511 
6512   // Anything too big to fit in registers is passed with an explicit indirect
6513   // pointer / sret pointer.
6514   if (Size > SizeLimit)
6515     return getNaturalAlignIndirect(Ty, /*ByVal=*/false);
6516 
6517   // Treat an enum type as its underlying type.
6518   if (const EnumType *EnumTy = Ty->getAs<EnumType>())
6519     Ty = EnumTy->getDecl()->getIntegerType();
6520 
6521   // Integer types smaller than a register are extended.
6522   if (Size < 64 && Ty->isIntegerType())
6523     return ABIArgInfo::getExtend();
6524 
6525   // Other non-aggregates go in registers.
6526   if (!isAggregateTypeForABI(Ty))
6527     return ABIArgInfo::getDirect();
6528 
6529   // If a C++ object has either a non-trivial copy constructor or a non-trivial
6530   // destructor, it is passed with an explicit indirect pointer / sret pointer.
6531   if (CGCXXABI::RecordArgABI RAA = getRecordArgABI(Ty, getCXXABI()))
6532     return getNaturalAlignIndirect(Ty, RAA == CGCXXABI::RAA_DirectInMemory);
6533 
6534   // This is a small aggregate type that should be passed in registers.
6535   // Build a coercion type from the LLVM struct type.
6536   llvm::StructType *StrTy = dyn_cast<llvm::StructType>(CGT.ConvertType(Ty));
6537   if (!StrTy)
6538     return ABIArgInfo::getDirect();
6539 
6540   CoerceBuilder CB(getVMContext(), getDataLayout());
6541   CB.addStruct(0, StrTy);
6542   CB.pad(llvm::RoundUpToAlignment(CB.DL.getTypeSizeInBits(StrTy), 64));
6543 
6544   // Try to use the original type for coercion.
6545   llvm::Type *CoerceTy = CB.isUsableType(StrTy) ? StrTy : CB.getType();
6546 
6547   if (CB.InReg)
6548     return ABIArgInfo::getDirectInReg(CoerceTy);
6549   else
6550     return ABIArgInfo::getDirect(CoerceTy);
6551 }
6552 
6553 Address SparcV9ABIInfo::EmitVAArg(CodeGenFunction &CGF, Address VAListAddr,
6554                                   QualType Ty) const {
6555   ABIArgInfo AI = classifyType(Ty, 16 * 8);
6556   llvm::Type *ArgTy = CGT.ConvertType(Ty);
6557   if (AI.canHaveCoerceToType() && !AI.getCoerceToType())
6558     AI.setCoerceToType(ArgTy);
6559 
6560   CharUnits SlotSize = CharUnits::fromQuantity(8);
6561 
6562   CGBuilderTy &Builder = CGF.Builder;
6563   Address Addr(Builder.CreateLoad(VAListAddr, "ap.cur"), SlotSize);
6564   llvm::Type *ArgPtrTy = llvm::PointerType::getUnqual(ArgTy);
6565 
6566   auto TypeInfo = getContext().getTypeInfoInChars(Ty);
6567 
6568   Address ArgAddr = Address::invalid();
6569   CharUnits Stride;
6570   switch (AI.getKind()) {
6571   case ABIArgInfo::Expand:
6572   case ABIArgInfo::InAlloca:
6573     llvm_unreachable("Unsupported ABI kind for va_arg");
6574 
6575   case ABIArgInfo::Extend: {
6576     Stride = SlotSize;
6577     CharUnits Offset = SlotSize - TypeInfo.first;
6578     ArgAddr = Builder.CreateConstInBoundsByteGEP(Addr, Offset, "extend");
6579     break;
6580   }
6581 
6582   case ABIArgInfo::Direct: {
6583     auto AllocSize = getDataLayout().getTypeAllocSize(AI.getCoerceToType());
6584     Stride = CharUnits::fromQuantity(AllocSize).RoundUpToAlignment(SlotSize);
6585     ArgAddr = Addr;
6586     break;
6587   }
6588 
6589   case ABIArgInfo::Indirect:
6590     Stride = SlotSize;
6591     ArgAddr = Builder.CreateElementBitCast(Addr, ArgPtrTy, "indirect");
6592     ArgAddr = Address(Builder.CreateLoad(ArgAddr, "indirect.arg"),
6593                       TypeInfo.second);
6594     break;
6595 
6596   case ABIArgInfo::Ignore:
6597     return Address(llvm::UndefValue::get(ArgPtrTy), TypeInfo.second);
6598   }
6599 
6600   // Update VAList.
6601   llvm::Value *NextPtr =
6602     Builder.CreateConstInBoundsByteGEP(Addr.getPointer(), Stride, "ap.next");
6603   Builder.CreateStore(NextPtr, VAListAddr);
6604 
6605   return Builder.CreateBitCast(ArgAddr, ArgPtrTy, "arg.addr");
6606 }
6607 
6608 void SparcV9ABIInfo::computeInfo(CGFunctionInfo &FI) const {
6609   FI.getReturnInfo() = classifyType(FI.getReturnType(), 32 * 8);
6610   for (auto &I : FI.arguments())
6611     I.info = classifyType(I.type, 16 * 8);
6612 }
6613 
6614 namespace {
6615 class SparcV9TargetCodeGenInfo : public TargetCodeGenInfo {
6616 public:
6617   SparcV9TargetCodeGenInfo(CodeGenTypes &CGT)
6618     : TargetCodeGenInfo(new SparcV9ABIInfo(CGT)) {}
6619 
6620   int getDwarfEHStackPointer(CodeGen::CodeGenModule &M) const override {
6621     return 14;
6622   }
6623 
6624   bool initDwarfEHRegSizeTable(CodeGen::CodeGenFunction &CGF,
6625                                llvm::Value *Address) const override;
6626 };
6627 } // end anonymous namespace
6628 
6629 bool
6630 SparcV9TargetCodeGenInfo::initDwarfEHRegSizeTable(CodeGen::CodeGenFunction &CGF,
6631                                                 llvm::Value *Address) const {
6632   // This is calculated from the LLVM and GCC tables and verified
6633   // against gcc output.  AFAIK all ABIs use the same encoding.
6634 
6635   CodeGen::CGBuilderTy &Builder = CGF.Builder;
6636 
6637   llvm::IntegerType *i8 = CGF.Int8Ty;
6638   llvm::Value *Four8 = llvm::ConstantInt::get(i8, 4);
6639   llvm::Value *Eight8 = llvm::ConstantInt::get(i8, 8);
6640 
6641   // 0-31: the 8-byte general-purpose registers
6642   AssignToArrayRange(Builder, Address, Eight8, 0, 31);
6643 
6644   // 32-63: f0-31, the 4-byte floating-point registers
6645   AssignToArrayRange(Builder, Address, Four8, 32, 63);
6646 
6647   //   Y   = 64
6648   //   PSR = 65
6649   //   WIM = 66
6650   //   TBR = 67
6651   //   PC  = 68
6652   //   NPC = 69
6653   //   FSR = 70
6654   //   CSR = 71
6655   AssignToArrayRange(Builder, Address, Eight8, 64, 71);
6656 
6657   // 72-87: d0-15, the 8-byte floating-point registers
6658   AssignToArrayRange(Builder, Address, Eight8, 72, 87);
6659 
6660   return false;
6661 }
6662 
6663 
6664 //===----------------------------------------------------------------------===//
6665 // XCore ABI Implementation
6666 //===----------------------------------------------------------------------===//
6667 
6668 namespace {
6669 
6670 /// A SmallStringEnc instance is used to build up the TypeString by passing
6671 /// it by reference between functions that append to it.
6672 typedef llvm::SmallString<128> SmallStringEnc;
6673 
6674 /// TypeStringCache caches the meta encodings of Types.
6675 ///
6676 /// The reason for caching TypeStrings is two fold:
6677 ///   1. To cache a type's encoding for later uses;
6678 ///   2. As a means to break recursive member type inclusion.
6679 ///
6680 /// A cache Entry can have a Status of:
6681 ///   NonRecursive:   The type encoding is not recursive;
6682 ///   Recursive:      The type encoding is recursive;
6683 ///   Incomplete:     An incomplete TypeString;
6684 ///   IncompleteUsed: An incomplete TypeString that has been used in a
6685 ///                   Recursive type encoding.
6686 ///
6687 /// A NonRecursive entry will have all of its sub-members expanded as fully
6688 /// as possible. Whilst it may contain types which are recursive, the type
6689 /// itself is not recursive and thus its encoding may be safely used whenever
6690 /// the type is encountered.
6691 ///
6692 /// A Recursive entry will have all of its sub-members expanded as fully as
6693 /// possible. The type itself is recursive and it may contain other types which
6694 /// are recursive. The Recursive encoding must not be used during the expansion
6695 /// of a recursive type's recursive branch. For simplicity the code uses
6696 /// IncompleteCount to reject all usage of Recursive encodings for member types.
6697 ///
6698 /// An Incomplete entry is always a RecordType and only encodes its
6699 /// identifier e.g. "s(S){}". Incomplete 'StubEnc' entries are ephemeral and
6700 /// are placed into the cache during type expansion as a means to identify and
6701 /// handle recursive inclusion of types as sub-members. If there is recursion
6702 /// the entry becomes IncompleteUsed.
6703 ///
6704 /// During the expansion of a RecordType's members:
6705 ///
6706 ///   If the cache contains a NonRecursive encoding for the member type, the
6707 ///   cached encoding is used;
6708 ///
6709 ///   If the cache contains a Recursive encoding for the member type, the
6710 ///   cached encoding is 'Swapped' out, as it may be incorrect, and...
6711 ///
6712 ///   If the member is a RecordType, an Incomplete encoding is placed into the
6713 ///   cache to break potential recursive inclusion of itself as a sub-member;
6714 ///
6715 ///   Once a member RecordType has been expanded, its temporary incomplete
6716 ///   entry is removed from the cache. If a Recursive encoding was swapped out
6717 ///   it is swapped back in;
6718 ///
6719 ///   If an incomplete entry is used to expand a sub-member, the incomplete
6720 ///   entry is marked as IncompleteUsed. The cache keeps count of how many
6721 ///   IncompleteUsed entries it currently contains in IncompleteUsedCount;
6722 ///
6723 ///   If a member's encoding is found to be a NonRecursive or Recursive viz:
6724 ///   IncompleteUsedCount==0, the member's encoding is added to the cache.
6725 ///   Else the member is part of a recursive type and thus the recursion has
6726 ///   been exited too soon for the encoding to be correct for the member.
6727 ///
6728 class TypeStringCache {
6729   enum Status {NonRecursive, Recursive, Incomplete, IncompleteUsed};
6730   struct Entry {
6731     std::string Str;     // The encoded TypeString for the type.
6732     enum Status State;   // Information about the encoding in 'Str'.
6733     std::string Swapped; // A temporary place holder for a Recursive encoding
6734                          // during the expansion of RecordType's members.
6735   };
6736   std::map<const IdentifierInfo *, struct Entry> Map;
6737   unsigned IncompleteCount;     // Number of Incomplete entries in the Map.
6738   unsigned IncompleteUsedCount; // Number of IncompleteUsed entries in the Map.
6739 public:
6740   TypeStringCache() : IncompleteCount(0), IncompleteUsedCount(0) {}
6741   void addIncomplete(const IdentifierInfo *ID, std::string StubEnc);
6742   bool removeIncomplete(const IdentifierInfo *ID);
6743   void addIfComplete(const IdentifierInfo *ID, StringRef Str,
6744                      bool IsRecursive);
6745   StringRef lookupStr(const IdentifierInfo *ID);
6746 };
6747 
6748 /// TypeString encodings for enum & union fields must be order.
6749 /// FieldEncoding is a helper for this ordering process.
6750 class FieldEncoding {
6751   bool HasName;
6752   std::string Enc;
6753 public:
6754   FieldEncoding(bool b, SmallStringEnc &e) : HasName(b), Enc(e.c_str()) {}
6755   StringRef str() {return Enc.c_str();}
6756   bool operator<(const FieldEncoding &rhs) const {
6757     if (HasName != rhs.HasName) return HasName;
6758     return Enc < rhs.Enc;
6759   }
6760 };
6761 
6762 class XCoreABIInfo : public DefaultABIInfo {
6763 public:
6764   XCoreABIInfo(CodeGen::CodeGenTypes &CGT) : DefaultABIInfo(CGT) {}
6765   Address EmitVAArg(CodeGenFunction &CGF, Address VAListAddr,
6766                     QualType Ty) const override;
6767 };
6768 
6769 class XCoreTargetCodeGenInfo : public TargetCodeGenInfo {
6770   mutable TypeStringCache TSC;
6771 public:
6772   XCoreTargetCodeGenInfo(CodeGenTypes &CGT)
6773     :TargetCodeGenInfo(new XCoreABIInfo(CGT)) {}
6774   void emitTargetMD(const Decl *D, llvm::GlobalValue *GV,
6775                     CodeGen::CodeGenModule &M) const override;
6776 };
6777 
6778 } // End anonymous namespace.
6779 
6780 Address XCoreABIInfo::EmitVAArg(CodeGenFunction &CGF, Address VAListAddr,
6781                                 QualType Ty) const {
6782   CGBuilderTy &Builder = CGF.Builder;
6783 
6784   // Get the VAList.
6785   CharUnits SlotSize = CharUnits::fromQuantity(4);
6786   Address AP(Builder.CreateLoad(VAListAddr), SlotSize);
6787 
6788   // Handle the argument.
6789   ABIArgInfo AI = classifyArgumentType(Ty);
6790   CharUnits TypeAlign = getContext().getTypeAlignInChars(Ty);
6791   llvm::Type *ArgTy = CGT.ConvertType(Ty);
6792   if (AI.canHaveCoerceToType() && !AI.getCoerceToType())
6793     AI.setCoerceToType(ArgTy);
6794   llvm::Type *ArgPtrTy = llvm::PointerType::getUnqual(ArgTy);
6795 
6796   Address Val = Address::invalid();
6797   CharUnits ArgSize = CharUnits::Zero();
6798   switch (AI.getKind()) {
6799   case ABIArgInfo::Expand:
6800   case ABIArgInfo::InAlloca:
6801     llvm_unreachable("Unsupported ABI kind for va_arg");
6802   case ABIArgInfo::Ignore:
6803     Val = Address(llvm::UndefValue::get(ArgPtrTy), TypeAlign);
6804     ArgSize = CharUnits::Zero();
6805     break;
6806   case ABIArgInfo::Extend:
6807   case ABIArgInfo::Direct:
6808     Val = Builder.CreateBitCast(AP, ArgPtrTy);
6809     ArgSize = CharUnits::fromQuantity(
6810                        getDataLayout().getTypeAllocSize(AI.getCoerceToType()));
6811     ArgSize = ArgSize.RoundUpToAlignment(SlotSize);
6812     break;
6813   case ABIArgInfo::Indirect:
6814     Val = Builder.CreateElementBitCast(AP, ArgPtrTy);
6815     Val = Address(Builder.CreateLoad(Val), TypeAlign);
6816     ArgSize = SlotSize;
6817     break;
6818   }
6819 
6820   // Increment the VAList.
6821   if (!ArgSize.isZero()) {
6822     llvm::Value *APN =
6823       Builder.CreateConstInBoundsByteGEP(AP.getPointer(), ArgSize);
6824     Builder.CreateStore(APN, VAListAddr);
6825   }
6826 
6827   return Val;
6828 }
6829 
6830 /// During the expansion of a RecordType, an incomplete TypeString is placed
6831 /// into the cache as a means to identify and break recursion.
6832 /// If there is a Recursive encoding in the cache, it is swapped out and will
6833 /// be reinserted by removeIncomplete().
6834 /// All other types of encoding should have been used rather than arriving here.
6835 void TypeStringCache::addIncomplete(const IdentifierInfo *ID,
6836                                     std::string StubEnc) {
6837   if (!ID)
6838     return;
6839   Entry &E = Map[ID];
6840   assert( (E.Str.empty() || E.State == Recursive) &&
6841          "Incorrectly use of addIncomplete");
6842   assert(!StubEnc.empty() && "Passing an empty string to addIncomplete()");
6843   E.Swapped.swap(E.Str); // swap out the Recursive
6844   E.Str.swap(StubEnc);
6845   E.State = Incomplete;
6846   ++IncompleteCount;
6847 }
6848 
6849 /// Once the RecordType has been expanded, the temporary incomplete TypeString
6850 /// must be removed from the cache.
6851 /// If a Recursive was swapped out by addIncomplete(), it will be replaced.
6852 /// Returns true if the RecordType was defined recursively.
6853 bool TypeStringCache::removeIncomplete(const IdentifierInfo *ID) {
6854   if (!ID)
6855     return false;
6856   auto I = Map.find(ID);
6857   assert(I != Map.end() && "Entry not present");
6858   Entry &E = I->second;
6859   assert( (E.State == Incomplete ||
6860            E.State == IncompleteUsed) &&
6861          "Entry must be an incomplete type");
6862   bool IsRecursive = false;
6863   if (E.State == IncompleteUsed) {
6864     // We made use of our Incomplete encoding, thus we are recursive.
6865     IsRecursive = true;
6866     --IncompleteUsedCount;
6867   }
6868   if (E.Swapped.empty())
6869     Map.erase(I);
6870   else {
6871     // Swap the Recursive back.
6872     E.Swapped.swap(E.Str);
6873     E.Swapped.clear();
6874     E.State = Recursive;
6875   }
6876   --IncompleteCount;
6877   return IsRecursive;
6878 }
6879 
6880 /// Add the encoded TypeString to the cache only if it is NonRecursive or
6881 /// Recursive (viz: all sub-members were expanded as fully as possible).
6882 void TypeStringCache::addIfComplete(const IdentifierInfo *ID, StringRef Str,
6883                                     bool IsRecursive) {
6884   if (!ID || IncompleteUsedCount)
6885     return; // No key or it is is an incomplete sub-type so don't add.
6886   Entry &E = Map[ID];
6887   if (IsRecursive && !E.Str.empty()) {
6888     assert(E.State==Recursive && E.Str.size() == Str.size() &&
6889            "This is not the same Recursive entry");
6890     // The parent container was not recursive after all, so we could have used
6891     // this Recursive sub-member entry after all, but we assumed the worse when
6892     // we started viz: IncompleteCount!=0.
6893     return;
6894   }
6895   assert(E.Str.empty() && "Entry already present");
6896   E.Str = Str.str();
6897   E.State = IsRecursive? Recursive : NonRecursive;
6898 }
6899 
6900 /// Return a cached TypeString encoding for the ID. If there isn't one, or we
6901 /// are recursively expanding a type (IncompleteCount != 0) and the cached
6902 /// encoding is Recursive, return an empty StringRef.
6903 StringRef TypeStringCache::lookupStr(const IdentifierInfo *ID) {
6904   if (!ID)
6905     return StringRef();   // We have no key.
6906   auto I = Map.find(ID);
6907   if (I == Map.end())
6908     return StringRef();   // We have no encoding.
6909   Entry &E = I->second;
6910   if (E.State == Recursive && IncompleteCount)
6911     return StringRef();   // We don't use Recursive encodings for member types.
6912 
6913   if (E.State == Incomplete) {
6914     // The incomplete type is being used to break out of recursion.
6915     E.State = IncompleteUsed;
6916     ++IncompleteUsedCount;
6917   }
6918   return E.Str.c_str();
6919 }
6920 
6921 /// The XCore ABI includes a type information section that communicates symbol
6922 /// type information to the linker. The linker uses this information to verify
6923 /// safety/correctness of things such as array bound and pointers et al.
6924 /// The ABI only requires C (and XC) language modules to emit TypeStrings.
6925 /// This type information (TypeString) is emitted into meta data for all global
6926 /// symbols: definitions, declarations, functions & variables.
6927 ///
6928 /// The TypeString carries type, qualifier, name, size & value details.
6929 /// Please see 'Tools Development Guide' section 2.16.2 for format details:
6930 /// https://www.xmos.com/download/public/Tools-Development-Guide%28X9114A%29.pdf
6931 /// The output is tested by test/CodeGen/xcore-stringtype.c.
6932 ///
6933 static bool getTypeString(SmallStringEnc &Enc, const Decl *D,
6934                           CodeGen::CodeGenModule &CGM, TypeStringCache &TSC);
6935 
6936 /// XCore uses emitTargetMD to emit TypeString metadata for global symbols.
6937 void XCoreTargetCodeGenInfo::emitTargetMD(const Decl *D, llvm::GlobalValue *GV,
6938                                           CodeGen::CodeGenModule &CGM) const {
6939   SmallStringEnc Enc;
6940   if (getTypeString(Enc, D, CGM, TSC)) {
6941     llvm::LLVMContext &Ctx = CGM.getModule().getContext();
6942     llvm::SmallVector<llvm::Metadata *, 2> MDVals;
6943     MDVals.push_back(llvm::ConstantAsMetadata::get(GV));
6944     MDVals.push_back(llvm::MDString::get(Ctx, Enc.str()));
6945     llvm::NamedMDNode *MD =
6946       CGM.getModule().getOrInsertNamedMetadata("xcore.typestrings");
6947     MD->addOperand(llvm::MDNode::get(Ctx, MDVals));
6948   }
6949 }
6950 
6951 static bool appendType(SmallStringEnc &Enc, QualType QType,
6952                        const CodeGen::CodeGenModule &CGM,
6953                        TypeStringCache &TSC);
6954 
6955 /// Helper function for appendRecordType().
6956 /// Builds a SmallVector containing the encoded field types in declaration
6957 /// order.
6958 static bool extractFieldType(SmallVectorImpl<FieldEncoding> &FE,
6959                              const RecordDecl *RD,
6960                              const CodeGen::CodeGenModule &CGM,
6961                              TypeStringCache &TSC) {
6962   for (const auto *Field : RD->fields()) {
6963     SmallStringEnc Enc;
6964     Enc += "m(";
6965     Enc += Field->getName();
6966     Enc += "){";
6967     if (Field->isBitField()) {
6968       Enc += "b(";
6969       llvm::raw_svector_ostream OS(Enc);
6970       OS << Field->getBitWidthValue(CGM.getContext());
6971       Enc += ':';
6972     }
6973     if (!appendType(Enc, Field->getType(), CGM, TSC))
6974       return false;
6975     if (Field->isBitField())
6976       Enc += ')';
6977     Enc += '}';
6978     FE.emplace_back(!Field->getName().empty(), Enc);
6979   }
6980   return true;
6981 }
6982 
6983 /// Appends structure and union types to Enc and adds encoding to cache.
6984 /// Recursively calls appendType (via extractFieldType) for each field.
6985 /// Union types have their fields ordered according to the ABI.
6986 static bool appendRecordType(SmallStringEnc &Enc, const RecordType *RT,
6987                              const CodeGen::CodeGenModule &CGM,
6988                              TypeStringCache &TSC, const IdentifierInfo *ID) {
6989   // Append the cached TypeString if we have one.
6990   StringRef TypeString = TSC.lookupStr(ID);
6991   if (!TypeString.empty()) {
6992     Enc += TypeString;
6993     return true;
6994   }
6995 
6996   // Start to emit an incomplete TypeString.
6997   size_t Start = Enc.size();
6998   Enc += (RT->isUnionType()? 'u' : 's');
6999   Enc += '(';
7000   if (ID)
7001     Enc += ID->getName();
7002   Enc += "){";
7003 
7004   // We collect all encoded fields and order as necessary.
7005   bool IsRecursive = false;
7006   const RecordDecl *RD = RT->getDecl()->getDefinition();
7007   if (RD && !RD->field_empty()) {
7008     // An incomplete TypeString stub is placed in the cache for this RecordType
7009     // so that recursive calls to this RecordType will use it whilst building a
7010     // complete TypeString for this RecordType.
7011     SmallVector<FieldEncoding, 16> FE;
7012     std::string StubEnc(Enc.substr(Start).str());
7013     StubEnc += '}';  // StubEnc now holds a valid incomplete TypeString.
7014     TSC.addIncomplete(ID, std::move(StubEnc));
7015     if (!extractFieldType(FE, RD, CGM, TSC)) {
7016       (void) TSC.removeIncomplete(ID);
7017       return false;
7018     }
7019     IsRecursive = TSC.removeIncomplete(ID);
7020     // The ABI requires unions to be sorted but not structures.
7021     // See FieldEncoding::operator< for sort algorithm.
7022     if (RT->isUnionType())
7023       std::sort(FE.begin(), FE.end());
7024     // We can now complete the TypeString.
7025     unsigned E = FE.size();
7026     for (unsigned I = 0; I != E; ++I) {
7027       if (I)
7028         Enc += ',';
7029       Enc += FE[I].str();
7030     }
7031   }
7032   Enc += '}';
7033   TSC.addIfComplete(ID, Enc.substr(Start), IsRecursive);
7034   return true;
7035 }
7036 
7037 /// Appends enum types to Enc and adds the encoding to the cache.
7038 static bool appendEnumType(SmallStringEnc &Enc, const EnumType *ET,
7039                            TypeStringCache &TSC,
7040                            const IdentifierInfo *ID) {
7041   // Append the cached TypeString if we have one.
7042   StringRef TypeString = TSC.lookupStr(ID);
7043   if (!TypeString.empty()) {
7044     Enc += TypeString;
7045     return true;
7046   }
7047 
7048   size_t Start = Enc.size();
7049   Enc += "e(";
7050   if (ID)
7051     Enc += ID->getName();
7052   Enc += "){";
7053 
7054   // We collect all encoded enumerations and order them alphanumerically.
7055   if (const EnumDecl *ED = ET->getDecl()->getDefinition()) {
7056     SmallVector<FieldEncoding, 16> FE;
7057     for (auto I = ED->enumerator_begin(), E = ED->enumerator_end(); I != E;
7058          ++I) {
7059       SmallStringEnc EnumEnc;
7060       EnumEnc += "m(";
7061       EnumEnc += I->getName();
7062       EnumEnc += "){";
7063       I->getInitVal().toString(EnumEnc);
7064       EnumEnc += '}';
7065       FE.push_back(FieldEncoding(!I->getName().empty(), EnumEnc));
7066     }
7067     std::sort(FE.begin(), FE.end());
7068     unsigned E = FE.size();
7069     for (unsigned I = 0; I != E; ++I) {
7070       if (I)
7071         Enc += ',';
7072       Enc += FE[I].str();
7073     }
7074   }
7075   Enc += '}';
7076   TSC.addIfComplete(ID, Enc.substr(Start), false);
7077   return true;
7078 }
7079 
7080 /// Appends type's qualifier to Enc.
7081 /// This is done prior to appending the type's encoding.
7082 static void appendQualifier(SmallStringEnc &Enc, QualType QT) {
7083   // Qualifiers are emitted in alphabetical order.
7084   static const char *const Table[]={"","c:","r:","cr:","v:","cv:","rv:","crv:"};
7085   int Lookup = 0;
7086   if (QT.isConstQualified())
7087     Lookup += 1<<0;
7088   if (QT.isRestrictQualified())
7089     Lookup += 1<<1;
7090   if (QT.isVolatileQualified())
7091     Lookup += 1<<2;
7092   Enc += Table[Lookup];
7093 }
7094 
7095 /// Appends built-in types to Enc.
7096 static bool appendBuiltinType(SmallStringEnc &Enc, const BuiltinType *BT) {
7097   const char *EncType;
7098   switch (BT->getKind()) {
7099     case BuiltinType::Void:
7100       EncType = "0";
7101       break;
7102     case BuiltinType::Bool:
7103       EncType = "b";
7104       break;
7105     case BuiltinType::Char_U:
7106       EncType = "uc";
7107       break;
7108     case BuiltinType::UChar:
7109       EncType = "uc";
7110       break;
7111     case BuiltinType::SChar:
7112       EncType = "sc";
7113       break;
7114     case BuiltinType::UShort:
7115       EncType = "us";
7116       break;
7117     case BuiltinType::Short:
7118       EncType = "ss";
7119       break;
7120     case BuiltinType::UInt:
7121       EncType = "ui";
7122       break;
7123     case BuiltinType::Int:
7124       EncType = "si";
7125       break;
7126     case BuiltinType::ULong:
7127       EncType = "ul";
7128       break;
7129     case BuiltinType::Long:
7130       EncType = "sl";
7131       break;
7132     case BuiltinType::ULongLong:
7133       EncType = "ull";
7134       break;
7135     case BuiltinType::LongLong:
7136       EncType = "sll";
7137       break;
7138     case BuiltinType::Float:
7139       EncType = "ft";
7140       break;
7141     case BuiltinType::Double:
7142       EncType = "d";
7143       break;
7144     case BuiltinType::LongDouble:
7145       EncType = "ld";
7146       break;
7147     default:
7148       return false;
7149   }
7150   Enc += EncType;
7151   return true;
7152 }
7153 
7154 /// Appends a pointer encoding to Enc before calling appendType for the pointee.
7155 static bool appendPointerType(SmallStringEnc &Enc, const PointerType *PT,
7156                               const CodeGen::CodeGenModule &CGM,
7157                               TypeStringCache &TSC) {
7158   Enc += "p(";
7159   if (!appendType(Enc, PT->getPointeeType(), CGM, TSC))
7160     return false;
7161   Enc += ')';
7162   return true;
7163 }
7164 
7165 /// Appends array encoding to Enc before calling appendType for the element.
7166 static bool appendArrayType(SmallStringEnc &Enc, QualType QT,
7167                             const ArrayType *AT,
7168                             const CodeGen::CodeGenModule &CGM,
7169                             TypeStringCache &TSC, StringRef NoSizeEnc) {
7170   if (AT->getSizeModifier() != ArrayType::Normal)
7171     return false;
7172   Enc += "a(";
7173   if (const ConstantArrayType *CAT = dyn_cast<ConstantArrayType>(AT))
7174     CAT->getSize().toStringUnsigned(Enc);
7175   else
7176     Enc += NoSizeEnc; // Global arrays use "*", otherwise it is "".
7177   Enc += ':';
7178   // The Qualifiers should be attached to the type rather than the array.
7179   appendQualifier(Enc, QT);
7180   if (!appendType(Enc, AT->getElementType(), CGM, TSC))
7181     return false;
7182   Enc += ')';
7183   return true;
7184 }
7185 
7186 /// Appends a function encoding to Enc, calling appendType for the return type
7187 /// and the arguments.
7188 static bool appendFunctionType(SmallStringEnc &Enc, const FunctionType *FT,
7189                              const CodeGen::CodeGenModule &CGM,
7190                              TypeStringCache &TSC) {
7191   Enc += "f{";
7192   if (!appendType(Enc, FT->getReturnType(), CGM, TSC))
7193     return false;
7194   Enc += "}(";
7195   if (const FunctionProtoType *FPT = FT->getAs<FunctionProtoType>()) {
7196     // N.B. we are only interested in the adjusted param types.
7197     auto I = FPT->param_type_begin();
7198     auto E = FPT->param_type_end();
7199     if (I != E) {
7200       do {
7201         if (!appendType(Enc, *I, CGM, TSC))
7202           return false;
7203         ++I;
7204         if (I != E)
7205           Enc += ',';
7206       } while (I != E);
7207       if (FPT->isVariadic())
7208         Enc += ",va";
7209     } else {
7210       if (FPT->isVariadic())
7211         Enc += "va";
7212       else
7213         Enc += '0';
7214     }
7215   }
7216   Enc += ')';
7217   return true;
7218 }
7219 
7220 /// Handles the type's qualifier before dispatching a call to handle specific
7221 /// type encodings.
7222 static bool appendType(SmallStringEnc &Enc, QualType QType,
7223                        const CodeGen::CodeGenModule &CGM,
7224                        TypeStringCache &TSC) {
7225 
7226   QualType QT = QType.getCanonicalType();
7227 
7228   if (const ArrayType *AT = QT->getAsArrayTypeUnsafe())
7229     // The Qualifiers should be attached to the type rather than the array.
7230     // Thus we don't call appendQualifier() here.
7231     return appendArrayType(Enc, QT, AT, CGM, TSC, "");
7232 
7233   appendQualifier(Enc, QT);
7234 
7235   if (const BuiltinType *BT = QT->getAs<BuiltinType>())
7236     return appendBuiltinType(Enc, BT);
7237 
7238   if (const PointerType *PT = QT->getAs<PointerType>())
7239     return appendPointerType(Enc, PT, CGM, TSC);
7240 
7241   if (const EnumType *ET = QT->getAs<EnumType>())
7242     return appendEnumType(Enc, ET, TSC, QT.getBaseTypeIdentifier());
7243 
7244   if (const RecordType *RT = QT->getAsStructureType())
7245     return appendRecordType(Enc, RT, CGM, TSC, QT.getBaseTypeIdentifier());
7246 
7247   if (const RecordType *RT = QT->getAsUnionType())
7248     return appendRecordType(Enc, RT, CGM, TSC, QT.getBaseTypeIdentifier());
7249 
7250   if (const FunctionType *FT = QT->getAs<FunctionType>())
7251     return appendFunctionType(Enc, FT, CGM, TSC);
7252 
7253   return false;
7254 }
7255 
7256 static bool getTypeString(SmallStringEnc &Enc, const Decl *D,
7257                           CodeGen::CodeGenModule &CGM, TypeStringCache &TSC) {
7258   if (!D)
7259     return false;
7260 
7261   if (const FunctionDecl *FD = dyn_cast<FunctionDecl>(D)) {
7262     if (FD->getLanguageLinkage() != CLanguageLinkage)
7263       return false;
7264     return appendType(Enc, FD->getType(), CGM, TSC);
7265   }
7266 
7267   if (const VarDecl *VD = dyn_cast<VarDecl>(D)) {
7268     if (VD->getLanguageLinkage() != CLanguageLinkage)
7269       return false;
7270     QualType QT = VD->getType().getCanonicalType();
7271     if (const ArrayType *AT = QT->getAsArrayTypeUnsafe()) {
7272       // Global ArrayTypes are given a size of '*' if the size is unknown.
7273       // The Qualifiers should be attached to the type rather than the array.
7274       // Thus we don't call appendQualifier() here.
7275       return appendArrayType(Enc, QT, AT, CGM, TSC, "*");
7276     }
7277     return appendType(Enc, QT, CGM, TSC);
7278   }
7279   return false;
7280 }
7281 
7282 
7283 //===----------------------------------------------------------------------===//
7284 // Driver code
7285 //===----------------------------------------------------------------------===//
7286 
7287 const llvm::Triple &CodeGenModule::getTriple() const {
7288   return getTarget().getTriple();
7289 }
7290 
7291 bool CodeGenModule::supportsCOMDAT() const {
7292   return !getTriple().isOSBinFormatMachO();
7293 }
7294 
7295 const TargetCodeGenInfo &CodeGenModule::getTargetCodeGenInfo() {
7296   if (TheTargetCodeGenInfo)
7297     return *TheTargetCodeGenInfo;
7298 
7299   const llvm::Triple &Triple = getTarget().getTriple();
7300   switch (Triple.getArch()) {
7301   default:
7302     return *(TheTargetCodeGenInfo = new DefaultTargetCodeGenInfo(Types));
7303 
7304   case llvm::Triple::le32:
7305     return *(TheTargetCodeGenInfo = new PNaClTargetCodeGenInfo(Types));
7306   case llvm::Triple::mips:
7307   case llvm::Triple::mipsel:
7308     if (Triple.getOS() == llvm::Triple::NaCl)
7309       return *(TheTargetCodeGenInfo = new PNaClTargetCodeGenInfo(Types));
7310     return *(TheTargetCodeGenInfo = new MIPSTargetCodeGenInfo(Types, true));
7311 
7312   case llvm::Triple::mips64:
7313   case llvm::Triple::mips64el:
7314     return *(TheTargetCodeGenInfo = new MIPSTargetCodeGenInfo(Types, false));
7315 
7316   case llvm::Triple::aarch64:
7317   case llvm::Triple::aarch64_be: {
7318     AArch64ABIInfo::ABIKind Kind = AArch64ABIInfo::AAPCS;
7319     if (getTarget().getABI() == "darwinpcs")
7320       Kind = AArch64ABIInfo::DarwinPCS;
7321 
7322     return *(TheTargetCodeGenInfo = new AArch64TargetCodeGenInfo(Types, Kind));
7323   }
7324 
7325   case llvm::Triple::wasm32:
7326   case llvm::Triple::wasm64:
7327     return *(TheTargetCodeGenInfo = new WebAssemblyTargetCodeGenInfo(Types));
7328 
7329   case llvm::Triple::arm:
7330   case llvm::Triple::armeb:
7331   case llvm::Triple::thumb:
7332   case llvm::Triple::thumbeb:
7333     {
7334       if (Triple.getOS() == llvm::Triple::Win32) {
7335         TheTargetCodeGenInfo =
7336             new WindowsARMTargetCodeGenInfo(Types, ARMABIInfo::AAPCS_VFP);
7337         return *TheTargetCodeGenInfo;
7338       }
7339 
7340       ARMABIInfo::ABIKind Kind = ARMABIInfo::AAPCS;
7341       if (getTarget().getABI() == "apcs-gnu")
7342         Kind = ARMABIInfo::APCS;
7343       else if (CodeGenOpts.FloatABI == "hard" ||
7344                (CodeGenOpts.FloatABI != "soft" &&
7345                 Triple.getEnvironment() == llvm::Triple::GNUEABIHF))
7346         Kind = ARMABIInfo::AAPCS_VFP;
7347 
7348       return *(TheTargetCodeGenInfo = new ARMTargetCodeGenInfo(Types, Kind));
7349     }
7350 
7351   case llvm::Triple::ppc:
7352     return *(TheTargetCodeGenInfo = new PPC32TargetCodeGenInfo(Types));
7353   case llvm::Triple::ppc64:
7354     if (Triple.isOSBinFormatELF()) {
7355       PPC64_SVR4_ABIInfo::ABIKind Kind = PPC64_SVR4_ABIInfo::ELFv1;
7356       if (getTarget().getABI() == "elfv2")
7357         Kind = PPC64_SVR4_ABIInfo::ELFv2;
7358       bool HasQPX = getTarget().getABI() == "elfv1-qpx";
7359 
7360       return *(TheTargetCodeGenInfo =
7361                new PPC64_SVR4_TargetCodeGenInfo(Types, Kind, HasQPX));
7362     } else
7363       return *(TheTargetCodeGenInfo = new PPC64TargetCodeGenInfo(Types));
7364   case llvm::Triple::ppc64le: {
7365     assert(Triple.isOSBinFormatELF() && "PPC64 LE non-ELF not supported!");
7366     PPC64_SVR4_ABIInfo::ABIKind Kind = PPC64_SVR4_ABIInfo::ELFv2;
7367     if (getTarget().getABI() == "elfv1" || getTarget().getABI() == "elfv1-qpx")
7368       Kind = PPC64_SVR4_ABIInfo::ELFv1;
7369     bool HasQPX = getTarget().getABI() == "elfv1-qpx";
7370 
7371     return *(TheTargetCodeGenInfo =
7372              new PPC64_SVR4_TargetCodeGenInfo(Types, Kind, HasQPX));
7373   }
7374 
7375   case llvm::Triple::nvptx:
7376   case llvm::Triple::nvptx64:
7377     return *(TheTargetCodeGenInfo = new NVPTXTargetCodeGenInfo(Types));
7378 
7379   case llvm::Triple::msp430:
7380     return *(TheTargetCodeGenInfo = new MSP430TargetCodeGenInfo(Types));
7381 
7382   case llvm::Triple::systemz: {
7383     bool HasVector = getTarget().getABI() == "vector";
7384     return *(TheTargetCodeGenInfo = new SystemZTargetCodeGenInfo(Types,
7385                                                                  HasVector));
7386   }
7387 
7388   case llvm::Triple::tce:
7389     return *(TheTargetCodeGenInfo = new TCETargetCodeGenInfo(Types));
7390 
7391   case llvm::Triple::x86: {
7392     bool IsDarwinVectorABI = Triple.isOSDarwin();
7393     bool RetSmallStructInRegABI =
7394         X86_32TargetCodeGenInfo::isStructReturnInRegABI(Triple, CodeGenOpts);
7395     bool IsWin32FloatStructABI = Triple.isOSWindows() && !Triple.isOSCygMing();
7396 
7397     if (Triple.getOS() == llvm::Triple::Win32) {
7398       return *(TheTargetCodeGenInfo = new WinX86_32TargetCodeGenInfo(
7399                    Types, IsDarwinVectorABI, RetSmallStructInRegABI,
7400                    IsWin32FloatStructABI, CodeGenOpts.NumRegisterParameters));
7401     } else {
7402       return *(TheTargetCodeGenInfo = new X86_32TargetCodeGenInfo(
7403                    Types, IsDarwinVectorABI, RetSmallStructInRegABI,
7404                    IsWin32FloatStructABI, CodeGenOpts.NumRegisterParameters,
7405                    CodeGenOpts.FloatABI == "soft"));
7406     }
7407   }
7408 
7409   case llvm::Triple::x86_64: {
7410     StringRef ABI = getTarget().getABI();
7411     X86AVXABILevel AVXLevel = (ABI == "avx512" ? X86AVXABILevel::AVX512 :
7412                                ABI == "avx" ? X86AVXABILevel::AVX :
7413                                X86AVXABILevel::None);
7414 
7415     switch (Triple.getOS()) {
7416     case llvm::Triple::Win32:
7417       return *(TheTargetCodeGenInfo =
7418                    new WinX86_64TargetCodeGenInfo(Types, AVXLevel));
7419     case llvm::Triple::PS4:
7420       return *(TheTargetCodeGenInfo =
7421                    new PS4TargetCodeGenInfo(Types, AVXLevel));
7422     default:
7423       return *(TheTargetCodeGenInfo =
7424                    new X86_64TargetCodeGenInfo(Types, AVXLevel));
7425     }
7426   }
7427   case llvm::Triple::hexagon:
7428     return *(TheTargetCodeGenInfo = new HexagonTargetCodeGenInfo(Types));
7429   case llvm::Triple::r600:
7430     return *(TheTargetCodeGenInfo = new AMDGPUTargetCodeGenInfo(Types));
7431   case llvm::Triple::amdgcn:
7432     return *(TheTargetCodeGenInfo = new AMDGPUTargetCodeGenInfo(Types));
7433   case llvm::Triple::sparcv9:
7434     return *(TheTargetCodeGenInfo = new SparcV9TargetCodeGenInfo(Types));
7435   case llvm::Triple::xcore:
7436     return *(TheTargetCodeGenInfo = new XCoreTargetCodeGenInfo(Types));
7437   }
7438 }
7439