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 "CodeGenFunction.h"
19 #include "clang/AST/RecordLayout.h"
20 #include "clang/CodeGen/CGFunctionInfo.h"
21 #include "clang/Frontend/CodeGenOptions.h"
22 #include "llvm/ADT/Triple.h"
23 #include "llvm/IR/DataLayout.h"
24 #include "llvm/IR/Type.h"
25 #include "llvm/Support/raw_ostream.h"
26 
27 #include <algorithm>    // std::sort
28 
29 using namespace clang;
30 using namespace CodeGen;
31 
32 static void AssignToArrayRange(CodeGen::CGBuilderTy &Builder,
33                                llvm::Value *Array,
34                                llvm::Value *Value,
35                                unsigned FirstIndex,
36                                unsigned LastIndex) {
37   // Alternatively, we could emit this as a loop in the source.
38   for (unsigned I = FirstIndex; I <= LastIndex; ++I) {
39     llvm::Value *Cell = Builder.CreateConstInBoundsGEP1_32(Array, I);
40     Builder.CreateStore(Value, Cell);
41   }
42 }
43 
44 static bool isAggregateTypeForABI(QualType T) {
45   return !CodeGenFunction::hasScalarEvaluationKind(T) ||
46          T->isMemberFunctionPointerType();
47 }
48 
49 ABIInfo::~ABIInfo() {}
50 
51 static CGCXXABI::RecordArgABI getRecordArgABI(const RecordType *RT,
52                                               CGCXXABI &CXXABI) {
53   const CXXRecordDecl *RD = dyn_cast<CXXRecordDecl>(RT->getDecl());
54   if (!RD)
55     return CGCXXABI::RAA_Default;
56   return CXXABI.getRecordArgABI(RD);
57 }
58 
59 static CGCXXABI::RecordArgABI getRecordArgABI(QualType T,
60                                               CGCXXABI &CXXABI) {
61   const RecordType *RT = T->getAs<RecordType>();
62   if (!RT)
63     return CGCXXABI::RAA_Default;
64   return getRecordArgABI(RT, CXXABI);
65 }
66 
67 CGCXXABI &ABIInfo::getCXXABI() const {
68   return CGT.getCXXABI();
69 }
70 
71 ASTContext &ABIInfo::getContext() const {
72   return CGT.getContext();
73 }
74 
75 llvm::LLVMContext &ABIInfo::getVMContext() const {
76   return CGT.getLLVMContext();
77 }
78 
79 const llvm::DataLayout &ABIInfo::getDataLayout() const {
80   return CGT.getDataLayout();
81 }
82 
83 const TargetInfo &ABIInfo::getTarget() const {
84   return CGT.getTarget();
85 }
86 
87 void ABIArgInfo::dump() const {
88   raw_ostream &OS = llvm::errs();
89   OS << "(ABIArgInfo Kind=";
90   switch (TheKind) {
91   case Direct:
92     OS << "Direct Type=";
93     if (llvm::Type *Ty = getCoerceToType())
94       Ty->print(OS);
95     else
96       OS << "null";
97     break;
98   case Extend:
99     OS << "Extend";
100     break;
101   case Ignore:
102     OS << "Ignore";
103     break;
104   case InAlloca:
105     OS << "InAlloca Offset=" << getInAllocaFieldIndex();
106     break;
107   case Indirect:
108     OS << "Indirect Align=" << getIndirectAlign()
109        << " ByVal=" << getIndirectByVal()
110        << " Realign=" << getIndirectRealign();
111     break;
112   case Expand:
113     OS << "Expand";
114     break;
115   }
116   OS << ")\n";
117 }
118 
119 TargetCodeGenInfo::~TargetCodeGenInfo() { delete Info; }
120 
121 // If someone can figure out a general rule for this, that would be great.
122 // It's probably just doomed to be platform-dependent, though.
123 unsigned TargetCodeGenInfo::getSizeOfUnwindException() const {
124   // Verified for:
125   //   x86-64     FreeBSD, Linux, Darwin
126   //   x86-32     FreeBSD, Linux, Darwin
127   //   PowerPC    Linux, Darwin
128   //   ARM        Darwin (*not* EABI)
129   //   AArch64    Linux
130   return 32;
131 }
132 
133 bool TargetCodeGenInfo::isNoProtoCallVariadic(const CallArgList &args,
134                                      const FunctionNoProtoType *fnType) const {
135   // The following conventions are known to require this to be false:
136   //   x86_stdcall
137   //   MIPS
138   // For everything else, we just prefer false unless we opt out.
139   return false;
140 }
141 
142 void
143 TargetCodeGenInfo::getDependentLibraryOption(llvm::StringRef Lib,
144                                              llvm::SmallString<24> &Opt) const {
145   // This assumes the user is passing a library name like "rt" instead of a
146   // filename like "librt.a/so", and that they don't care whether it's static or
147   // dynamic.
148   Opt = "-l";
149   Opt += Lib;
150 }
151 
152 static bool isEmptyRecord(ASTContext &Context, QualType T, bool AllowArrays);
153 
154 /// isEmptyField - Return true iff a the field is "empty", that is it
155 /// is an unnamed bit-field or an (array of) empty record(s).
156 static bool isEmptyField(ASTContext &Context, const FieldDecl *FD,
157                          bool AllowArrays) {
158   if (FD->isUnnamedBitfield())
159     return true;
160 
161   QualType FT = FD->getType();
162 
163   // Constant arrays of empty records count as empty, strip them off.
164   // Constant arrays of zero length always count as empty.
165   if (AllowArrays)
166     while (const ConstantArrayType *AT = Context.getAsConstantArrayType(FT)) {
167       if (AT->getSize() == 0)
168         return true;
169       FT = AT->getElementType();
170     }
171 
172   const RecordType *RT = FT->getAs<RecordType>();
173   if (!RT)
174     return false;
175 
176   // C++ record fields are never empty, at least in the Itanium ABI.
177   //
178   // FIXME: We should use a predicate for whether this behavior is true in the
179   // current ABI.
180   if (isa<CXXRecordDecl>(RT->getDecl()))
181     return false;
182 
183   return isEmptyRecord(Context, FT, AllowArrays);
184 }
185 
186 /// isEmptyRecord - Return true iff a structure contains only empty
187 /// fields. Note that a structure with a flexible array member is not
188 /// considered empty.
189 static bool isEmptyRecord(ASTContext &Context, QualType T, bool AllowArrays) {
190   const RecordType *RT = T->getAs<RecordType>();
191   if (!RT)
192     return 0;
193   const RecordDecl *RD = RT->getDecl();
194   if (RD->hasFlexibleArrayMember())
195     return false;
196 
197   // If this is a C++ record, check the bases first.
198   if (const CXXRecordDecl *CXXRD = dyn_cast<CXXRecordDecl>(RD))
199     for (const auto &I : CXXRD->bases())
200       if (!isEmptyRecord(Context, I.getType(), true))
201         return false;
202 
203   for (const auto *I : RD->fields())
204     if (!isEmptyField(Context, I, AllowArrays))
205       return false;
206   return true;
207 }
208 
209 /// isSingleElementStruct - Determine if a structure is a "single
210 /// element struct", i.e. it has exactly one non-empty field or
211 /// exactly one field which is itself a single element
212 /// struct. Structures with flexible array members are never
213 /// considered single element structs.
214 ///
215 /// \return The field declaration for the single non-empty field, if
216 /// it exists.
217 static const Type *isSingleElementStruct(QualType T, ASTContext &Context) {
218   const RecordType *RT = T->getAsStructureType();
219   if (!RT)
220     return nullptr;
221 
222   const RecordDecl *RD = RT->getDecl();
223   if (RD->hasFlexibleArrayMember())
224     return nullptr;
225 
226   const Type *Found = nullptr;
227 
228   // If this is a C++ record, check the bases first.
229   if (const CXXRecordDecl *CXXRD = dyn_cast<CXXRecordDecl>(RD)) {
230     for (const auto &I : CXXRD->bases()) {
231       // Ignore empty records.
232       if (isEmptyRecord(Context, I.getType(), true))
233         continue;
234 
235       // If we already found an element then this isn't a single-element struct.
236       if (Found)
237         return nullptr;
238 
239       // If this is non-empty and not a single element struct, the composite
240       // cannot be a single element struct.
241       Found = isSingleElementStruct(I.getType(), Context);
242       if (!Found)
243         return nullptr;
244     }
245   }
246 
247   // Check for single element.
248   for (const auto *FD : RD->fields()) {
249     QualType FT = FD->getType();
250 
251     // Ignore empty fields.
252     if (isEmptyField(Context, FD, true))
253       continue;
254 
255     // If we already found an element then this isn't a single-element
256     // struct.
257     if (Found)
258       return nullptr;
259 
260     // Treat single element arrays as the element.
261     while (const ConstantArrayType *AT = Context.getAsConstantArrayType(FT)) {
262       if (AT->getSize().getZExtValue() != 1)
263         break;
264       FT = AT->getElementType();
265     }
266 
267     if (!isAggregateTypeForABI(FT)) {
268       Found = FT.getTypePtr();
269     } else {
270       Found = isSingleElementStruct(FT, Context);
271       if (!Found)
272         return nullptr;
273     }
274   }
275 
276   // We don't consider a struct a single-element struct if it has
277   // padding beyond the element type.
278   if (Found && Context.getTypeSize(Found) != Context.getTypeSize(T))
279     return nullptr;
280 
281   return Found;
282 }
283 
284 static bool is32Or64BitBasicType(QualType Ty, ASTContext &Context) {
285   // Treat complex types as the element type.
286   if (const ComplexType *CTy = Ty->getAs<ComplexType>())
287     Ty = CTy->getElementType();
288 
289   // Check for a type which we know has a simple scalar argument-passing
290   // convention without any padding.  (We're specifically looking for 32
291   // and 64-bit integer and integer-equivalents, float, and double.)
292   if (!Ty->getAs<BuiltinType>() && !Ty->hasPointerRepresentation() &&
293       !Ty->isEnumeralType() && !Ty->isBlockPointerType())
294     return false;
295 
296   uint64_t Size = Context.getTypeSize(Ty);
297   return Size == 32 || Size == 64;
298 }
299 
300 /// canExpandIndirectArgument - Test whether an argument type which is to be
301 /// passed indirectly (on the stack) would have the equivalent layout if it was
302 /// expanded into separate arguments. If so, we prefer to do the latter to avoid
303 /// inhibiting optimizations.
304 ///
305 // FIXME: This predicate is missing many cases, currently it just follows
306 // llvm-gcc (checks that all fields are 32-bit or 64-bit primitive types). We
307 // should probably make this smarter, or better yet make the LLVM backend
308 // capable of handling it.
309 static bool canExpandIndirectArgument(QualType Ty, ASTContext &Context) {
310   // We can only expand structure types.
311   const RecordType *RT = Ty->getAs<RecordType>();
312   if (!RT)
313     return false;
314 
315   // We can only expand (C) structures.
316   //
317   // FIXME: This needs to be generalized to handle classes as well.
318   const RecordDecl *RD = RT->getDecl();
319   if (!RD->isStruct() || isa<CXXRecordDecl>(RD))
320     return false;
321 
322   uint64_t Size = 0;
323 
324   for (const auto *FD : RD->fields()) {
325     if (!is32Or64BitBasicType(FD->getType(), Context))
326       return false;
327 
328     // FIXME: Reject bit-fields wholesale; there are two problems, we don't know
329     // how to expand them yet, and the predicate for telling if a bitfield still
330     // counts as "basic" is more complicated than what we were doing previously.
331     if (FD->isBitField())
332       return false;
333 
334     Size += Context.getTypeSize(FD->getType());
335   }
336 
337   // Make sure there are not any holes in the struct.
338   if (Size != Context.getTypeSize(Ty))
339     return false;
340 
341   return true;
342 }
343 
344 namespace {
345 /// DefaultABIInfo - The default implementation for ABI specific
346 /// details. This implementation provides information which results in
347 /// self-consistent and sensible LLVM IR generation, but does not
348 /// conform to any particular ABI.
349 class DefaultABIInfo : public ABIInfo {
350 public:
351   DefaultABIInfo(CodeGen::CodeGenTypes &CGT) : ABIInfo(CGT) {}
352 
353   ABIArgInfo classifyReturnType(QualType RetTy) const;
354   ABIArgInfo classifyArgumentType(QualType RetTy) const;
355 
356   void computeInfo(CGFunctionInfo &FI) const override {
357     if (!getCXXABI().classifyReturnType(FI))
358       FI.getReturnInfo() = classifyReturnType(FI.getReturnType());
359     for (auto &I : FI.arguments())
360       I.info = classifyArgumentType(I.type);
361   }
362 
363   llvm::Value *EmitVAArg(llvm::Value *VAListAddr, QualType Ty,
364                          CodeGenFunction &CGF) const override;
365 };
366 
367 class DefaultTargetCodeGenInfo : public TargetCodeGenInfo {
368 public:
369   DefaultTargetCodeGenInfo(CodeGen::CodeGenTypes &CGT)
370     : TargetCodeGenInfo(new DefaultABIInfo(CGT)) {}
371 };
372 
373 llvm::Value *DefaultABIInfo::EmitVAArg(llvm::Value *VAListAddr, QualType Ty,
374                                        CodeGenFunction &CGF) const {
375   return nullptr;
376 }
377 
378 ABIArgInfo DefaultABIInfo::classifyArgumentType(QualType Ty) const {
379   if (isAggregateTypeForABI(Ty))
380     return ABIArgInfo::getIndirect(0);
381 
382   // Treat an enum type as its underlying type.
383   if (const EnumType *EnumTy = Ty->getAs<EnumType>())
384     Ty = EnumTy->getDecl()->getIntegerType();
385 
386   return (Ty->isPromotableIntegerType() ?
387           ABIArgInfo::getExtend() : ABIArgInfo::getDirect());
388 }
389 
390 ABIArgInfo DefaultABIInfo::classifyReturnType(QualType RetTy) const {
391   if (RetTy->isVoidType())
392     return ABIArgInfo::getIgnore();
393 
394   if (isAggregateTypeForABI(RetTy))
395     return ABIArgInfo::getIndirect(0);
396 
397   // Treat an enum type as its underlying type.
398   if (const EnumType *EnumTy = RetTy->getAs<EnumType>())
399     RetTy = EnumTy->getDecl()->getIntegerType();
400 
401   return (RetTy->isPromotableIntegerType() ?
402           ABIArgInfo::getExtend() : ABIArgInfo::getDirect());
403 }
404 
405 //===----------------------------------------------------------------------===//
406 // le32/PNaCl bitcode ABI Implementation
407 //
408 // This is a simplified version of the x86_32 ABI.  Arguments and return values
409 // are always passed on the stack.
410 //===----------------------------------------------------------------------===//
411 
412 class PNaClABIInfo : public ABIInfo {
413  public:
414   PNaClABIInfo(CodeGen::CodeGenTypes &CGT) : ABIInfo(CGT) {}
415 
416   ABIArgInfo classifyReturnType(QualType RetTy) const;
417   ABIArgInfo classifyArgumentType(QualType RetTy) const;
418 
419   void computeInfo(CGFunctionInfo &FI) const override;
420   llvm::Value *EmitVAArg(llvm::Value *VAListAddr, QualType Ty,
421                          CodeGenFunction &CGF) const override;
422 };
423 
424 class PNaClTargetCodeGenInfo : public TargetCodeGenInfo {
425  public:
426   PNaClTargetCodeGenInfo(CodeGen::CodeGenTypes &CGT)
427     : TargetCodeGenInfo(new PNaClABIInfo(CGT)) {}
428 };
429 
430 void PNaClABIInfo::computeInfo(CGFunctionInfo &FI) const {
431   if (!getCXXABI().classifyReturnType(FI))
432     FI.getReturnInfo() = classifyReturnType(FI.getReturnType());
433 
434   for (auto &I : FI.arguments())
435     I.info = classifyArgumentType(I.type);
436 }
437 
438 llvm::Value *PNaClABIInfo::EmitVAArg(llvm::Value *VAListAddr, QualType Ty,
439                                        CodeGenFunction &CGF) const {
440   return nullptr;
441 }
442 
443 /// \brief Classify argument of given type \p Ty.
444 ABIArgInfo PNaClABIInfo::classifyArgumentType(QualType Ty) const {
445   if (isAggregateTypeForABI(Ty)) {
446     if (CGCXXABI::RecordArgABI RAA = getRecordArgABI(Ty, getCXXABI()))
447       return ABIArgInfo::getIndirect(0, RAA == CGCXXABI::RAA_DirectInMemory);
448     return ABIArgInfo::getIndirect(0);
449   } else if (const EnumType *EnumTy = Ty->getAs<EnumType>()) {
450     // Treat an enum type as its underlying type.
451     Ty = EnumTy->getDecl()->getIntegerType();
452   } else if (Ty->isFloatingType()) {
453     // Floating-point types don't go inreg.
454     return ABIArgInfo::getDirect();
455   }
456 
457   return (Ty->isPromotableIntegerType() ?
458           ABIArgInfo::getExtend() : ABIArgInfo::getDirect());
459 }
460 
461 ABIArgInfo PNaClABIInfo::classifyReturnType(QualType RetTy) const {
462   if (RetTy->isVoidType())
463     return ABIArgInfo::getIgnore();
464 
465   // In the PNaCl ABI we always return records/structures on the stack.
466   if (isAggregateTypeForABI(RetTy))
467     return ABIArgInfo::getIndirect(0);
468 
469   // Treat an enum type as its underlying type.
470   if (const EnumType *EnumTy = RetTy->getAs<EnumType>())
471     RetTy = EnumTy->getDecl()->getIntegerType();
472 
473   return (RetTy->isPromotableIntegerType() ?
474           ABIArgInfo::getExtend() : ABIArgInfo::getDirect());
475 }
476 
477 /// IsX86_MMXType - Return true if this is an MMX type.
478 bool IsX86_MMXType(llvm::Type *IRType) {
479   // Return true if the type is an MMX type <2 x i32>, <4 x i16>, or <8 x i8>.
480   return IRType->isVectorTy() && IRType->getPrimitiveSizeInBits() == 64 &&
481     cast<llvm::VectorType>(IRType)->getElementType()->isIntegerTy() &&
482     IRType->getScalarSizeInBits() != 64;
483 }
484 
485 static llvm::Type* X86AdjustInlineAsmType(CodeGen::CodeGenFunction &CGF,
486                                           StringRef Constraint,
487                                           llvm::Type* Ty) {
488   if ((Constraint == "y" || Constraint == "&y") && Ty->isVectorTy()) {
489     if (cast<llvm::VectorType>(Ty)->getBitWidth() != 64) {
490       // Invalid MMX constraint
491       return nullptr;
492     }
493 
494     return llvm::Type::getX86_MMXTy(CGF.getLLVMContext());
495   }
496 
497   // No operation needed
498   return Ty;
499 }
500 
501 //===----------------------------------------------------------------------===//
502 // X86-32 ABI Implementation
503 //===----------------------------------------------------------------------===//
504 
505 /// \brief Similar to llvm::CCState, but for Clang.
506 struct CCState {
507   CCState(unsigned CC) : CC(CC), FreeRegs(0) {}
508 
509   unsigned CC;
510   unsigned FreeRegs;
511   unsigned StackOffset;
512   bool UseInAlloca;
513 };
514 
515 /// X86_32ABIInfo - The X86-32 ABI information.
516 class X86_32ABIInfo : public ABIInfo {
517   enum Class {
518     Integer,
519     Float
520   };
521 
522   static const unsigned MinABIStackAlignInBytes = 4;
523 
524   bool IsDarwinVectorABI;
525   bool IsSmallStructInRegABI;
526   bool IsWin32StructABI;
527   unsigned DefaultNumRegisterParameters;
528 
529   static bool isRegisterSize(unsigned Size) {
530     return (Size == 8 || Size == 16 || Size == 32 || Size == 64);
531   }
532 
533   bool shouldReturnTypeInRegister(QualType Ty, ASTContext &Context) const;
534 
535   /// getIndirectResult - Give a source type \arg Ty, return a suitable result
536   /// such that the argument will be passed in memory.
537   ABIArgInfo getIndirectResult(QualType Ty, bool ByVal, CCState &State) const;
538 
539   ABIArgInfo getIndirectReturnResult(CCState &State) const;
540 
541   /// \brief Return the alignment to use for the given type on the stack.
542   unsigned getTypeStackAlignInBytes(QualType Ty, unsigned Align) const;
543 
544   Class classify(QualType Ty) const;
545   ABIArgInfo classifyReturnType(QualType RetTy, CCState &State) const;
546   ABIArgInfo classifyArgumentType(QualType RetTy, CCState &State) const;
547   bool shouldUseInReg(QualType Ty, CCState &State, bool &NeedsPadding) const;
548 
549   /// \brief Rewrite the function info so that all memory arguments use
550   /// inalloca.
551   void rewriteWithInAlloca(CGFunctionInfo &FI) const;
552 
553   void addFieldToArgStruct(SmallVector<llvm::Type *, 6> &FrameFields,
554                            unsigned &StackOffset, ABIArgInfo &Info,
555                            QualType Type) const;
556 
557 public:
558 
559   void computeInfo(CGFunctionInfo &FI) const override;
560   llvm::Value *EmitVAArg(llvm::Value *VAListAddr, QualType Ty,
561                          CodeGenFunction &CGF) const override;
562 
563   X86_32ABIInfo(CodeGen::CodeGenTypes &CGT, bool d, bool p, bool w,
564                 unsigned r)
565     : ABIInfo(CGT), IsDarwinVectorABI(d), IsSmallStructInRegABI(p),
566       IsWin32StructABI(w), DefaultNumRegisterParameters(r) {}
567 };
568 
569 class X86_32TargetCodeGenInfo : public TargetCodeGenInfo {
570 public:
571   X86_32TargetCodeGenInfo(CodeGen::CodeGenTypes &CGT,
572       bool d, bool p, bool w, unsigned r)
573     :TargetCodeGenInfo(new X86_32ABIInfo(CGT, d, p, w, r)) {}
574 
575   static bool isStructReturnInRegABI(
576       const llvm::Triple &Triple, const CodeGenOptions &Opts);
577 
578   void SetTargetAttributes(const Decl *D, llvm::GlobalValue *GV,
579                            CodeGen::CodeGenModule &CGM) const override;
580 
581   int getDwarfEHStackPointer(CodeGen::CodeGenModule &CGM) const override {
582     // Darwin uses different dwarf register numbers for EH.
583     if (CGM.getTarget().getTriple().isOSDarwin()) return 5;
584     return 4;
585   }
586 
587   bool initDwarfEHRegSizeTable(CodeGen::CodeGenFunction &CGF,
588                                llvm::Value *Address) const override;
589 
590   llvm::Type* adjustInlineAsmType(CodeGen::CodeGenFunction &CGF,
591                                   StringRef Constraint,
592                                   llvm::Type* Ty) const override {
593     return X86AdjustInlineAsmType(CGF, Constraint, Ty);
594   }
595 
596   llvm::Constant *
597   getUBSanFunctionSignature(CodeGen::CodeGenModule &CGM) const override {
598     unsigned Sig = (0xeb << 0) |  // jmp rel8
599                    (0x06 << 8) |  //           .+0x08
600                    ('F' << 16) |
601                    ('T' << 24);
602     return llvm::ConstantInt::get(CGM.Int32Ty, Sig);
603   }
604 
605 };
606 
607 }
608 
609 /// shouldReturnTypeInRegister - Determine if the given type should be
610 /// passed in a register (for the Darwin ABI).
611 bool X86_32ABIInfo::shouldReturnTypeInRegister(QualType Ty,
612                                                ASTContext &Context) const {
613   uint64_t Size = Context.getTypeSize(Ty);
614 
615   // Type must be register sized.
616   if (!isRegisterSize(Size))
617     return false;
618 
619   if (Ty->isVectorType()) {
620     // 64- and 128- bit vectors inside structures are not returned in
621     // registers.
622     if (Size == 64 || Size == 128)
623       return false;
624 
625     return true;
626   }
627 
628   // If this is a builtin, pointer, enum, complex type, member pointer, or
629   // member function pointer it is ok.
630   if (Ty->getAs<BuiltinType>() || Ty->hasPointerRepresentation() ||
631       Ty->isAnyComplexType() || Ty->isEnumeralType() ||
632       Ty->isBlockPointerType() || Ty->isMemberPointerType())
633     return true;
634 
635   // Arrays are treated like records.
636   if (const ConstantArrayType *AT = Context.getAsConstantArrayType(Ty))
637     return shouldReturnTypeInRegister(AT->getElementType(), Context);
638 
639   // Otherwise, it must be a record type.
640   const RecordType *RT = Ty->getAs<RecordType>();
641   if (!RT) return false;
642 
643   // FIXME: Traverse bases here too.
644 
645   // Structure types are passed in register if all fields would be
646   // passed in a register.
647   for (const auto *FD : RT->getDecl()->fields()) {
648     // Empty fields are ignored.
649     if (isEmptyField(Context, FD, true))
650       continue;
651 
652     // Check fields recursively.
653     if (!shouldReturnTypeInRegister(FD->getType(), Context))
654       return false;
655   }
656   return true;
657 }
658 
659 ABIArgInfo X86_32ABIInfo::getIndirectReturnResult(CCState &State) const {
660   // If the return value is indirect, then the hidden argument is consuming one
661   // integer register.
662   if (State.FreeRegs) {
663     --State.FreeRegs;
664     return ABIArgInfo::getIndirectInReg(/*Align=*/0, /*ByVal=*/false);
665   }
666   return ABIArgInfo::getIndirect(/*Align=*/0, /*ByVal=*/false);
667 }
668 
669 ABIArgInfo X86_32ABIInfo::classifyReturnType(QualType RetTy, CCState &State) const {
670   if (RetTy->isVoidType())
671     return ABIArgInfo::getIgnore();
672 
673   if (const VectorType *VT = RetTy->getAs<VectorType>()) {
674     // On Darwin, some vectors are returned in registers.
675     if (IsDarwinVectorABI) {
676       uint64_t Size = getContext().getTypeSize(RetTy);
677 
678       // 128-bit vectors are a special case; they are returned in
679       // registers and we need to make sure to pick a type the LLVM
680       // backend will like.
681       if (Size == 128)
682         return ABIArgInfo::getDirect(llvm::VectorType::get(
683                   llvm::Type::getInt64Ty(getVMContext()), 2));
684 
685       // Always return in register if it fits in a general purpose
686       // register, or if it is 64 bits and has a single element.
687       if ((Size == 8 || Size == 16 || Size == 32) ||
688           (Size == 64 && VT->getNumElements() == 1))
689         return ABIArgInfo::getDirect(llvm::IntegerType::get(getVMContext(),
690                                                             Size));
691 
692       return getIndirectReturnResult(State);
693     }
694 
695     return ABIArgInfo::getDirect();
696   }
697 
698   if (isAggregateTypeForABI(RetTy)) {
699     if (const RecordType *RT = RetTy->getAs<RecordType>()) {
700       // Structures with flexible arrays are always indirect.
701       if (RT->getDecl()->hasFlexibleArrayMember())
702         return getIndirectReturnResult(State);
703     }
704 
705     // If specified, structs and unions are always indirect.
706     if (!IsSmallStructInRegABI && !RetTy->isAnyComplexType())
707       return getIndirectReturnResult(State);
708 
709     // Small structures which are register sized are generally returned
710     // in a register.
711     if (shouldReturnTypeInRegister(RetTy, getContext())) {
712       uint64_t Size = getContext().getTypeSize(RetTy);
713 
714       // As a special-case, if the struct is a "single-element" struct, and
715       // the field is of type "float" or "double", return it in a
716       // floating-point register. (MSVC does not apply this special case.)
717       // We apply a similar transformation for pointer types to improve the
718       // quality of the generated IR.
719       if (const Type *SeltTy = isSingleElementStruct(RetTy, getContext()))
720         if ((!IsWin32StructABI && SeltTy->isRealFloatingType())
721             || SeltTy->hasPointerRepresentation())
722           return ABIArgInfo::getDirect(CGT.ConvertType(QualType(SeltTy, 0)));
723 
724       // FIXME: We should be able to narrow this integer in cases with dead
725       // padding.
726       return ABIArgInfo::getDirect(llvm::IntegerType::get(getVMContext(),Size));
727     }
728 
729     return getIndirectReturnResult(State);
730   }
731 
732   // Treat an enum type as its underlying type.
733   if (const EnumType *EnumTy = RetTy->getAs<EnumType>())
734     RetTy = EnumTy->getDecl()->getIntegerType();
735 
736   return (RetTy->isPromotableIntegerType() ?
737           ABIArgInfo::getExtend() : ABIArgInfo::getDirect());
738 }
739 
740 static bool isSSEVectorType(ASTContext &Context, QualType Ty) {
741   return Ty->getAs<VectorType>() && Context.getTypeSize(Ty) == 128;
742 }
743 
744 static bool isRecordWithSSEVectorType(ASTContext &Context, QualType Ty) {
745   const RecordType *RT = Ty->getAs<RecordType>();
746   if (!RT)
747     return 0;
748   const RecordDecl *RD = RT->getDecl();
749 
750   // If this is a C++ record, check the bases first.
751   if (const CXXRecordDecl *CXXRD = dyn_cast<CXXRecordDecl>(RD))
752     for (const auto &I : CXXRD->bases())
753       if (!isRecordWithSSEVectorType(Context, I.getType()))
754         return false;
755 
756   for (const auto *i : RD->fields()) {
757     QualType FT = i->getType();
758 
759     if (isSSEVectorType(Context, FT))
760       return true;
761 
762     if (isRecordWithSSEVectorType(Context, FT))
763       return true;
764   }
765 
766   return false;
767 }
768 
769 unsigned X86_32ABIInfo::getTypeStackAlignInBytes(QualType Ty,
770                                                  unsigned Align) const {
771   // Otherwise, if the alignment is less than or equal to the minimum ABI
772   // alignment, just use the default; the backend will handle this.
773   if (Align <= MinABIStackAlignInBytes)
774     return 0; // Use default alignment.
775 
776   // On non-Darwin, the stack type alignment is always 4.
777   if (!IsDarwinVectorABI) {
778     // Set explicit alignment, since we may need to realign the top.
779     return MinABIStackAlignInBytes;
780   }
781 
782   // Otherwise, if the type contains an SSE vector type, the alignment is 16.
783   if (Align >= 16 && (isSSEVectorType(getContext(), Ty) ||
784                       isRecordWithSSEVectorType(getContext(), Ty)))
785     return 16;
786 
787   return MinABIStackAlignInBytes;
788 }
789 
790 ABIArgInfo X86_32ABIInfo::getIndirectResult(QualType Ty, bool ByVal,
791                                             CCState &State) const {
792   if (!ByVal) {
793     if (State.FreeRegs) {
794       --State.FreeRegs; // Non-byval indirects just use one pointer.
795       return ABIArgInfo::getIndirectInReg(0, false);
796     }
797     return ABIArgInfo::getIndirect(0, false);
798   }
799 
800   // Compute the byval alignment.
801   unsigned TypeAlign = getContext().getTypeAlign(Ty) / 8;
802   unsigned StackAlign = getTypeStackAlignInBytes(Ty, TypeAlign);
803   if (StackAlign == 0)
804     return ABIArgInfo::getIndirect(4, /*ByVal=*/true);
805 
806   // If the stack alignment is less than the type alignment, realign the
807   // argument.
808   bool Realign = TypeAlign > StackAlign;
809   return ABIArgInfo::getIndirect(StackAlign, /*ByVal=*/true, Realign);
810 }
811 
812 X86_32ABIInfo::Class X86_32ABIInfo::classify(QualType Ty) const {
813   const Type *T = isSingleElementStruct(Ty, getContext());
814   if (!T)
815     T = Ty.getTypePtr();
816 
817   if (const BuiltinType *BT = T->getAs<BuiltinType>()) {
818     BuiltinType::Kind K = BT->getKind();
819     if (K == BuiltinType::Float || K == BuiltinType::Double)
820       return Float;
821   }
822   return Integer;
823 }
824 
825 bool X86_32ABIInfo::shouldUseInReg(QualType Ty, CCState &State,
826                                    bool &NeedsPadding) const {
827   NeedsPadding = false;
828   Class C = classify(Ty);
829   if (C == Float)
830     return false;
831 
832   unsigned Size = getContext().getTypeSize(Ty);
833   unsigned SizeInRegs = (Size + 31) / 32;
834 
835   if (SizeInRegs == 0)
836     return false;
837 
838   if (SizeInRegs > State.FreeRegs) {
839     State.FreeRegs = 0;
840     return false;
841   }
842 
843   State.FreeRegs -= SizeInRegs;
844 
845   if (State.CC == llvm::CallingConv::X86_FastCall) {
846     if (Size > 32)
847       return false;
848 
849     if (Ty->isIntegralOrEnumerationType())
850       return true;
851 
852     if (Ty->isPointerType())
853       return true;
854 
855     if (Ty->isReferenceType())
856       return true;
857 
858     if (State.FreeRegs)
859       NeedsPadding = true;
860 
861     return false;
862   }
863 
864   return true;
865 }
866 
867 ABIArgInfo X86_32ABIInfo::classifyArgumentType(QualType Ty,
868                                                CCState &State) const {
869   // FIXME: Set alignment on indirect arguments.
870   if (isAggregateTypeForABI(Ty)) {
871     if (const RecordType *RT = Ty->getAs<RecordType>()) {
872       // Check with the C++ ABI first.
873       CGCXXABI::RecordArgABI RAA = getRecordArgABI(RT, getCXXABI());
874       if (RAA == CGCXXABI::RAA_Indirect) {
875         return getIndirectResult(Ty, false, State);
876       } else if (RAA == CGCXXABI::RAA_DirectInMemory) {
877         // The field index doesn't matter, we'll fix it up later.
878         return ABIArgInfo::getInAlloca(/*FieldIndex=*/0);
879       }
880 
881       // Structs are always byval on win32, regardless of what they contain.
882       if (IsWin32StructABI)
883         return getIndirectResult(Ty, true, State);
884 
885       // Structures with flexible arrays are always indirect.
886       if (RT->getDecl()->hasFlexibleArrayMember())
887         return getIndirectResult(Ty, true, State);
888     }
889 
890     // Ignore empty structs/unions.
891     if (isEmptyRecord(getContext(), Ty, true))
892       return ABIArgInfo::getIgnore();
893 
894     llvm::LLVMContext &LLVMContext = getVMContext();
895     llvm::IntegerType *Int32 = llvm::Type::getInt32Ty(LLVMContext);
896     bool NeedsPadding;
897     if (shouldUseInReg(Ty, State, NeedsPadding)) {
898       unsigned SizeInRegs = (getContext().getTypeSize(Ty) + 31) / 32;
899       SmallVector<llvm::Type*, 3> Elements(SizeInRegs, Int32);
900       llvm::Type *Result = llvm::StructType::get(LLVMContext, Elements);
901       return ABIArgInfo::getDirectInReg(Result);
902     }
903     llvm::IntegerType *PaddingType = NeedsPadding ? Int32 : nullptr;
904 
905     // Expand small (<= 128-bit) record types when we know that the stack layout
906     // of those arguments will match the struct. This is important because the
907     // LLVM backend isn't smart enough to remove byval, which inhibits many
908     // optimizations.
909     if (getContext().getTypeSize(Ty) <= 4*32 &&
910         canExpandIndirectArgument(Ty, getContext()))
911       return ABIArgInfo::getExpandWithPadding(
912           State.CC == llvm::CallingConv::X86_FastCall, PaddingType);
913 
914     return getIndirectResult(Ty, true, State);
915   }
916 
917   if (const VectorType *VT = Ty->getAs<VectorType>()) {
918     // On Darwin, some vectors are passed in memory, we handle this by passing
919     // it as an i8/i16/i32/i64.
920     if (IsDarwinVectorABI) {
921       uint64_t Size = getContext().getTypeSize(Ty);
922       if ((Size == 8 || Size == 16 || Size == 32) ||
923           (Size == 64 && VT->getNumElements() == 1))
924         return ABIArgInfo::getDirect(llvm::IntegerType::get(getVMContext(),
925                                                             Size));
926     }
927 
928     if (IsX86_MMXType(CGT.ConvertType(Ty)))
929       return ABIArgInfo::getDirect(llvm::IntegerType::get(getVMContext(), 64));
930 
931     return ABIArgInfo::getDirect();
932   }
933 
934 
935   if (const EnumType *EnumTy = Ty->getAs<EnumType>())
936     Ty = EnumTy->getDecl()->getIntegerType();
937 
938   bool NeedsPadding;
939   bool InReg = shouldUseInReg(Ty, State, NeedsPadding);
940 
941   if (Ty->isPromotableIntegerType()) {
942     if (InReg)
943       return ABIArgInfo::getExtendInReg();
944     return ABIArgInfo::getExtend();
945   }
946   if (InReg)
947     return ABIArgInfo::getDirectInReg();
948   return ABIArgInfo::getDirect();
949 }
950 
951 void X86_32ABIInfo::computeInfo(CGFunctionInfo &FI) const {
952   CCState State(FI.getCallingConvention());
953   if (State.CC == llvm::CallingConv::X86_FastCall)
954     State.FreeRegs = 2;
955   else if (FI.getHasRegParm())
956     State.FreeRegs = FI.getRegParm();
957   else
958     State.FreeRegs = DefaultNumRegisterParameters;
959 
960   if (!getCXXABI().classifyReturnType(FI)) {
961     FI.getReturnInfo() = classifyReturnType(FI.getReturnType(), State);
962   } else if (FI.getReturnInfo().isIndirect()) {
963     // The C++ ABI is not aware of register usage, so we have to check if the
964     // return value was sret and put it in a register ourselves if appropriate.
965     if (State.FreeRegs) {
966       --State.FreeRegs;  // The sret parameter consumes a register.
967       FI.getReturnInfo().setInReg(true);
968     }
969   }
970 
971   bool UsedInAlloca = false;
972   for (auto &I : FI.arguments()) {
973     I.info = classifyArgumentType(I.type, State);
974     UsedInAlloca |= (I.info.getKind() == ABIArgInfo::InAlloca);
975   }
976 
977   // If we needed to use inalloca for any argument, do a second pass and rewrite
978   // all the memory arguments to use inalloca.
979   if (UsedInAlloca)
980     rewriteWithInAlloca(FI);
981 }
982 
983 void
984 X86_32ABIInfo::addFieldToArgStruct(SmallVector<llvm::Type *, 6> &FrameFields,
985                                    unsigned &StackOffset,
986                                    ABIArgInfo &Info, QualType Type) const {
987   assert(StackOffset % 4U == 0 && "unaligned inalloca struct");
988   Info = ABIArgInfo::getInAlloca(FrameFields.size());
989   FrameFields.push_back(CGT.ConvertTypeForMem(Type));
990   StackOffset += getContext().getTypeSizeInChars(Type).getQuantity();
991 
992   // Insert padding bytes to respect alignment.  For x86_32, each argument is 4
993   // byte aligned.
994   if (StackOffset % 4U) {
995     unsigned OldOffset = StackOffset;
996     StackOffset = llvm::RoundUpToAlignment(StackOffset, 4U);
997     unsigned NumBytes = StackOffset - OldOffset;
998     assert(NumBytes);
999     llvm::Type *Ty = llvm::Type::getInt8Ty(getVMContext());
1000     Ty = llvm::ArrayType::get(Ty, NumBytes);
1001     FrameFields.push_back(Ty);
1002   }
1003 }
1004 
1005 void X86_32ABIInfo::rewriteWithInAlloca(CGFunctionInfo &FI) const {
1006   assert(IsWin32StructABI && "inalloca only supported on win32");
1007 
1008   // Build a packed struct type for all of the arguments in memory.
1009   SmallVector<llvm::Type *, 6> FrameFields;
1010 
1011   unsigned StackOffset = 0;
1012 
1013   // Put the sret parameter into the inalloca struct if it's in memory.
1014   ABIArgInfo &Ret = FI.getReturnInfo();
1015   if (Ret.isIndirect() && !Ret.getInReg()) {
1016     CanQualType PtrTy = getContext().getPointerType(FI.getReturnType());
1017     addFieldToArgStruct(FrameFields, StackOffset, Ret, PtrTy);
1018     // On Windows, the hidden sret parameter is always returned in eax.
1019     Ret.setInAllocaSRet(IsWin32StructABI);
1020   }
1021 
1022   // Skip the 'this' parameter in ecx.
1023   CGFunctionInfo::arg_iterator I = FI.arg_begin(), E = FI.arg_end();
1024   if (FI.getCallingConvention() == llvm::CallingConv::X86_ThisCall)
1025     ++I;
1026 
1027   // Put arguments passed in memory into the struct.
1028   for (; I != E; ++I) {
1029 
1030     // Leave ignored and inreg arguments alone.
1031     switch (I->info.getKind()) {
1032     case ABIArgInfo::Indirect:
1033       assert(I->info.getIndirectByVal());
1034       break;
1035     case ABIArgInfo::Ignore:
1036       continue;
1037     case ABIArgInfo::Direct:
1038     case ABIArgInfo::Extend:
1039       if (I->info.getInReg())
1040         continue;
1041       break;
1042     default:
1043       break;
1044     }
1045 
1046     addFieldToArgStruct(FrameFields, StackOffset, I->info, I->type);
1047   }
1048 
1049   FI.setArgStruct(llvm::StructType::get(getVMContext(), FrameFields,
1050                                         /*isPacked=*/true));
1051 }
1052 
1053 llvm::Value *X86_32ABIInfo::EmitVAArg(llvm::Value *VAListAddr, QualType Ty,
1054                                       CodeGenFunction &CGF) const {
1055   llvm::Type *BPP = CGF.Int8PtrPtrTy;
1056 
1057   CGBuilderTy &Builder = CGF.Builder;
1058   llvm::Value *VAListAddrAsBPP = Builder.CreateBitCast(VAListAddr, BPP,
1059                                                        "ap");
1060   llvm::Value *Addr = Builder.CreateLoad(VAListAddrAsBPP, "ap.cur");
1061 
1062   // Compute if the address needs to be aligned
1063   unsigned Align = CGF.getContext().getTypeAlignInChars(Ty).getQuantity();
1064   Align = getTypeStackAlignInBytes(Ty, Align);
1065   Align = std::max(Align, 4U);
1066   if (Align > 4) {
1067     // addr = (addr + align - 1) & -align;
1068     llvm::Value *Offset =
1069       llvm::ConstantInt::get(CGF.Int32Ty, Align - 1);
1070     Addr = CGF.Builder.CreateGEP(Addr, Offset);
1071     llvm::Value *AsInt = CGF.Builder.CreatePtrToInt(Addr,
1072                                                     CGF.Int32Ty);
1073     llvm::Value *Mask = llvm::ConstantInt::get(CGF.Int32Ty, -Align);
1074     Addr = CGF.Builder.CreateIntToPtr(CGF.Builder.CreateAnd(AsInt, Mask),
1075                                       Addr->getType(),
1076                                       "ap.cur.aligned");
1077   }
1078 
1079   llvm::Type *PTy =
1080     llvm::PointerType::getUnqual(CGF.ConvertType(Ty));
1081   llvm::Value *AddrTyped = Builder.CreateBitCast(Addr, PTy);
1082 
1083   uint64_t Offset =
1084     llvm::RoundUpToAlignment(CGF.getContext().getTypeSize(Ty) / 8, Align);
1085   llvm::Value *NextAddr =
1086     Builder.CreateGEP(Addr, llvm::ConstantInt::get(CGF.Int32Ty, Offset),
1087                       "ap.next");
1088   Builder.CreateStore(NextAddr, VAListAddrAsBPP);
1089 
1090   return AddrTyped;
1091 }
1092 
1093 bool X86_32TargetCodeGenInfo::isStructReturnInRegABI(
1094     const llvm::Triple &Triple, const CodeGenOptions &Opts) {
1095   assert(Triple.getArch() == llvm::Triple::x86);
1096 
1097   switch (Opts.getStructReturnConvention()) {
1098   case CodeGenOptions::SRCK_Default:
1099     break;
1100   case CodeGenOptions::SRCK_OnStack:  // -fpcc-struct-return
1101     return false;
1102   case CodeGenOptions::SRCK_InRegs:  // -freg-struct-return
1103     return true;
1104   }
1105 
1106   if (Triple.isOSDarwin())
1107     return true;
1108 
1109   switch (Triple.getOS()) {
1110   case llvm::Triple::AuroraUX:
1111   case llvm::Triple::DragonFly:
1112   case llvm::Triple::FreeBSD:
1113   case llvm::Triple::OpenBSD:
1114   case llvm::Triple::Bitrig:
1115     return true;
1116   case llvm::Triple::Win32:
1117     switch (Triple.getEnvironment()) {
1118     case llvm::Triple::UnknownEnvironment:
1119     case llvm::Triple::Cygnus:
1120     case llvm::Triple::GNU:
1121     case llvm::Triple::MSVC:
1122       return true;
1123     default:
1124       return false;
1125     }
1126   default:
1127     return false;
1128   }
1129 }
1130 
1131 void X86_32TargetCodeGenInfo::SetTargetAttributes(const Decl *D,
1132                                                   llvm::GlobalValue *GV,
1133                                             CodeGen::CodeGenModule &CGM) const {
1134   if (const FunctionDecl *FD = dyn_cast<FunctionDecl>(D)) {
1135     if (FD->hasAttr<X86ForceAlignArgPointerAttr>()) {
1136       // Get the LLVM function.
1137       llvm::Function *Fn = cast<llvm::Function>(GV);
1138 
1139       // Now add the 'alignstack' attribute with a value of 16.
1140       llvm::AttrBuilder B;
1141       B.addStackAlignmentAttr(16);
1142       Fn->addAttributes(llvm::AttributeSet::FunctionIndex,
1143                       llvm::AttributeSet::get(CGM.getLLVMContext(),
1144                                               llvm::AttributeSet::FunctionIndex,
1145                                               B));
1146     }
1147   }
1148 }
1149 
1150 bool X86_32TargetCodeGenInfo::initDwarfEHRegSizeTable(
1151                                                CodeGen::CodeGenFunction &CGF,
1152                                                llvm::Value *Address) const {
1153   CodeGen::CGBuilderTy &Builder = CGF.Builder;
1154 
1155   llvm::Value *Four8 = llvm::ConstantInt::get(CGF.Int8Ty, 4);
1156 
1157   // 0-7 are the eight integer registers;  the order is different
1158   //   on Darwin (for EH), but the range is the same.
1159   // 8 is %eip.
1160   AssignToArrayRange(Builder, Address, Four8, 0, 8);
1161 
1162   if (CGF.CGM.getTarget().getTriple().isOSDarwin()) {
1163     // 12-16 are st(0..4).  Not sure why we stop at 4.
1164     // These have size 16, which is sizeof(long double) on
1165     // platforms with 8-byte alignment for that type.
1166     llvm::Value *Sixteen8 = llvm::ConstantInt::get(CGF.Int8Ty, 16);
1167     AssignToArrayRange(Builder, Address, Sixteen8, 12, 16);
1168 
1169   } else {
1170     // 9 is %eflags, which doesn't get a size on Darwin for some
1171     // reason.
1172     Builder.CreateStore(Four8, Builder.CreateConstInBoundsGEP1_32(Address, 9));
1173 
1174     // 11-16 are st(0..5).  Not sure why we stop at 5.
1175     // These have size 12, which is sizeof(long double) on
1176     // platforms with 4-byte alignment for that type.
1177     llvm::Value *Twelve8 = llvm::ConstantInt::get(CGF.Int8Ty, 12);
1178     AssignToArrayRange(Builder, Address, Twelve8, 11, 16);
1179   }
1180 
1181   return false;
1182 }
1183 
1184 //===----------------------------------------------------------------------===//
1185 // X86-64 ABI Implementation
1186 //===----------------------------------------------------------------------===//
1187 
1188 
1189 namespace {
1190 /// X86_64ABIInfo - The X86_64 ABI information.
1191 class X86_64ABIInfo : public ABIInfo {
1192   enum Class {
1193     Integer = 0,
1194     SSE,
1195     SSEUp,
1196     X87,
1197     X87Up,
1198     ComplexX87,
1199     NoClass,
1200     Memory
1201   };
1202 
1203   /// merge - Implement the X86_64 ABI merging algorithm.
1204   ///
1205   /// Merge an accumulating classification \arg Accum with a field
1206   /// classification \arg Field.
1207   ///
1208   /// \param Accum - The accumulating classification. This should
1209   /// always be either NoClass or the result of a previous merge
1210   /// call. In addition, this should never be Memory (the caller
1211   /// should just return Memory for the aggregate).
1212   static Class merge(Class Accum, Class Field);
1213 
1214   /// postMerge - Implement the X86_64 ABI post merging algorithm.
1215   ///
1216   /// Post merger cleanup, reduces a malformed Hi and Lo pair to
1217   /// final MEMORY or SSE classes when necessary.
1218   ///
1219   /// \param AggregateSize - The size of the current aggregate in
1220   /// the classification process.
1221   ///
1222   /// \param Lo - The classification for the parts of the type
1223   /// residing in the low word of the containing object.
1224   ///
1225   /// \param Hi - The classification for the parts of the type
1226   /// residing in the higher words of the containing object.
1227   ///
1228   void postMerge(unsigned AggregateSize, Class &Lo, Class &Hi) const;
1229 
1230   /// classify - Determine the x86_64 register classes in which the
1231   /// given type T should be passed.
1232   ///
1233   /// \param Lo - The classification for the parts of the type
1234   /// residing in the low word of the containing object.
1235   ///
1236   /// \param Hi - The classification for the parts of the type
1237   /// residing in the high word of the containing object.
1238   ///
1239   /// \param OffsetBase - The bit offset of this type in the
1240   /// containing object.  Some parameters are classified different
1241   /// depending on whether they straddle an eightbyte boundary.
1242   ///
1243   /// \param isNamedArg - Whether the argument in question is a "named"
1244   /// argument, as used in AMD64-ABI 3.5.7.
1245   ///
1246   /// If a word is unused its result will be NoClass; if a type should
1247   /// be passed in Memory then at least the classification of \arg Lo
1248   /// will be Memory.
1249   ///
1250   /// The \arg Lo class will be NoClass iff the argument is ignored.
1251   ///
1252   /// If the \arg Lo class is ComplexX87, then the \arg Hi class will
1253   /// also be ComplexX87.
1254   void classify(QualType T, uint64_t OffsetBase, Class &Lo, Class &Hi,
1255                 bool isNamedArg) const;
1256 
1257   llvm::Type *GetByteVectorType(QualType Ty) const;
1258   llvm::Type *GetSSETypeAtOffset(llvm::Type *IRType,
1259                                  unsigned IROffset, QualType SourceTy,
1260                                  unsigned SourceOffset) const;
1261   llvm::Type *GetINTEGERTypeAtOffset(llvm::Type *IRType,
1262                                      unsigned IROffset, QualType SourceTy,
1263                                      unsigned SourceOffset) const;
1264 
1265   /// getIndirectResult - Give a source type \arg Ty, return a suitable result
1266   /// such that the argument will be returned in memory.
1267   ABIArgInfo getIndirectReturnResult(QualType Ty) const;
1268 
1269   /// getIndirectResult - Give a source type \arg Ty, return a suitable result
1270   /// such that the argument will be passed in memory.
1271   ///
1272   /// \param freeIntRegs - The number of free integer registers remaining
1273   /// available.
1274   ABIArgInfo getIndirectResult(QualType Ty, unsigned freeIntRegs) const;
1275 
1276   ABIArgInfo classifyReturnType(QualType RetTy) const;
1277 
1278   ABIArgInfo classifyArgumentType(QualType Ty,
1279                                   unsigned freeIntRegs,
1280                                   unsigned &neededInt,
1281                                   unsigned &neededSSE,
1282                                   bool isNamedArg) const;
1283 
1284   bool IsIllegalVectorType(QualType Ty) const;
1285 
1286   /// The 0.98 ABI revision clarified a lot of ambiguities,
1287   /// unfortunately in ways that were not always consistent with
1288   /// certain previous compilers.  In particular, platforms which
1289   /// required strict binary compatibility with older versions of GCC
1290   /// may need to exempt themselves.
1291   bool honorsRevision0_98() const {
1292     return !getTarget().getTriple().isOSDarwin();
1293   }
1294 
1295   bool HasAVX;
1296   // Some ABIs (e.g. X32 ABI and Native Client OS) use 32 bit pointers on
1297   // 64-bit hardware.
1298   bool Has64BitPointers;
1299 
1300 public:
1301   X86_64ABIInfo(CodeGen::CodeGenTypes &CGT, bool hasavx) :
1302       ABIInfo(CGT), HasAVX(hasavx),
1303       Has64BitPointers(CGT.getDataLayout().getPointerSize(0) == 8) {
1304   }
1305 
1306   bool isPassedUsingAVXType(QualType type) const {
1307     unsigned neededInt, neededSSE;
1308     // The freeIntRegs argument doesn't matter here.
1309     ABIArgInfo info = classifyArgumentType(type, 0, neededInt, neededSSE,
1310                                            /*isNamedArg*/true);
1311     if (info.isDirect()) {
1312       llvm::Type *ty = info.getCoerceToType();
1313       if (llvm::VectorType *vectorTy = dyn_cast_or_null<llvm::VectorType>(ty))
1314         return (vectorTy->getBitWidth() > 128);
1315     }
1316     return false;
1317   }
1318 
1319   void computeInfo(CGFunctionInfo &FI) const override;
1320 
1321   llvm::Value *EmitVAArg(llvm::Value *VAListAddr, QualType Ty,
1322                          CodeGenFunction &CGF) const override;
1323 };
1324 
1325 /// WinX86_64ABIInfo - The Windows X86_64 ABI information.
1326 class WinX86_64ABIInfo : public ABIInfo {
1327 
1328   ABIArgInfo classify(QualType Ty, bool IsReturnType) const;
1329 
1330 public:
1331   WinX86_64ABIInfo(CodeGen::CodeGenTypes &CGT) : ABIInfo(CGT) {}
1332 
1333   void computeInfo(CGFunctionInfo &FI) const override;
1334 
1335   llvm::Value *EmitVAArg(llvm::Value *VAListAddr, QualType Ty,
1336                          CodeGenFunction &CGF) const override;
1337 };
1338 
1339 class X86_64TargetCodeGenInfo : public TargetCodeGenInfo {
1340 public:
1341   X86_64TargetCodeGenInfo(CodeGen::CodeGenTypes &CGT, bool HasAVX)
1342       : TargetCodeGenInfo(new X86_64ABIInfo(CGT, HasAVX)) {}
1343 
1344   const X86_64ABIInfo &getABIInfo() const {
1345     return static_cast<const X86_64ABIInfo&>(TargetCodeGenInfo::getABIInfo());
1346   }
1347 
1348   int getDwarfEHStackPointer(CodeGen::CodeGenModule &CGM) const override {
1349     return 7;
1350   }
1351 
1352   bool initDwarfEHRegSizeTable(CodeGen::CodeGenFunction &CGF,
1353                                llvm::Value *Address) const override {
1354     llvm::Value *Eight8 = llvm::ConstantInt::get(CGF.Int8Ty, 8);
1355 
1356     // 0-15 are the 16 integer registers.
1357     // 16 is %rip.
1358     AssignToArrayRange(CGF.Builder, Address, Eight8, 0, 16);
1359     return false;
1360   }
1361 
1362   llvm::Type* adjustInlineAsmType(CodeGen::CodeGenFunction &CGF,
1363                                   StringRef Constraint,
1364                                   llvm::Type* Ty) const override {
1365     return X86AdjustInlineAsmType(CGF, Constraint, Ty);
1366   }
1367 
1368   bool isNoProtoCallVariadic(const CallArgList &args,
1369                              const FunctionNoProtoType *fnType) const override {
1370     // The default CC on x86-64 sets %al to the number of SSA
1371     // registers used, and GCC sets this when calling an unprototyped
1372     // function, so we override the default behavior.  However, don't do
1373     // that when AVX types are involved: the ABI explicitly states it is
1374     // undefined, and it doesn't work in practice because of how the ABI
1375     // defines varargs anyway.
1376     if (fnType->getCallConv() == CC_C) {
1377       bool HasAVXType = false;
1378       for (CallArgList::const_iterator
1379              it = args.begin(), ie = args.end(); it != ie; ++it) {
1380         if (getABIInfo().isPassedUsingAVXType(it->Ty)) {
1381           HasAVXType = true;
1382           break;
1383         }
1384       }
1385 
1386       if (!HasAVXType)
1387         return true;
1388     }
1389 
1390     return TargetCodeGenInfo::isNoProtoCallVariadic(args, fnType);
1391   }
1392 
1393   llvm::Constant *
1394   getUBSanFunctionSignature(CodeGen::CodeGenModule &CGM) const override {
1395     unsigned Sig = (0xeb << 0) |  // jmp rel8
1396                    (0x0a << 8) |  //           .+0x0c
1397                    ('F' << 16) |
1398                    ('T' << 24);
1399     return llvm::ConstantInt::get(CGM.Int32Ty, Sig);
1400   }
1401 
1402 };
1403 
1404 static std::string qualifyWindowsLibrary(llvm::StringRef Lib) {
1405   // If the argument does not end in .lib, automatically add the suffix. This
1406   // matches the behavior of MSVC.
1407   std::string ArgStr = Lib;
1408   if (!Lib.endswith_lower(".lib"))
1409     ArgStr += ".lib";
1410   return ArgStr;
1411 }
1412 
1413 class WinX86_32TargetCodeGenInfo : public X86_32TargetCodeGenInfo {
1414 public:
1415   WinX86_32TargetCodeGenInfo(CodeGen::CodeGenTypes &CGT,
1416         bool d, bool p, bool w, unsigned RegParms)
1417     : X86_32TargetCodeGenInfo(CGT, d, p, w, RegParms) {}
1418 
1419   void getDependentLibraryOption(llvm::StringRef Lib,
1420                                  llvm::SmallString<24> &Opt) const override {
1421     Opt = "/DEFAULTLIB:";
1422     Opt += qualifyWindowsLibrary(Lib);
1423   }
1424 
1425   void getDetectMismatchOption(llvm::StringRef Name,
1426                                llvm::StringRef Value,
1427                                llvm::SmallString<32> &Opt) const override {
1428     Opt = "/FAILIFMISMATCH:\"" + Name.str() + "=" + Value.str() + "\"";
1429   }
1430 };
1431 
1432 class WinX86_64TargetCodeGenInfo : public TargetCodeGenInfo {
1433 public:
1434   WinX86_64TargetCodeGenInfo(CodeGen::CodeGenTypes &CGT)
1435     : TargetCodeGenInfo(new WinX86_64ABIInfo(CGT)) {}
1436 
1437   int getDwarfEHStackPointer(CodeGen::CodeGenModule &CGM) const override {
1438     return 7;
1439   }
1440 
1441   bool initDwarfEHRegSizeTable(CodeGen::CodeGenFunction &CGF,
1442                                llvm::Value *Address) const override {
1443     llvm::Value *Eight8 = llvm::ConstantInt::get(CGF.Int8Ty, 8);
1444 
1445     // 0-15 are the 16 integer registers.
1446     // 16 is %rip.
1447     AssignToArrayRange(CGF.Builder, Address, Eight8, 0, 16);
1448     return false;
1449   }
1450 
1451   void getDependentLibraryOption(llvm::StringRef Lib,
1452                                  llvm::SmallString<24> &Opt) const override {
1453     Opt = "/DEFAULTLIB:";
1454     Opt += qualifyWindowsLibrary(Lib);
1455   }
1456 
1457   void getDetectMismatchOption(llvm::StringRef Name,
1458                                llvm::StringRef Value,
1459                                llvm::SmallString<32> &Opt) const override {
1460     Opt = "/FAILIFMISMATCH:\"" + Name.str() + "=" + Value.str() + "\"";
1461   }
1462 };
1463 
1464 }
1465 
1466 void X86_64ABIInfo::postMerge(unsigned AggregateSize, Class &Lo,
1467                               Class &Hi) const {
1468   // AMD64-ABI 3.2.3p2: Rule 5. Then a post merger cleanup is done:
1469   //
1470   // (a) If one of the classes is Memory, the whole argument is passed in
1471   //     memory.
1472   //
1473   // (b) If X87UP is not preceded by X87, the whole argument is passed in
1474   //     memory.
1475   //
1476   // (c) If the size of the aggregate exceeds two eightbytes and the first
1477   //     eightbyte isn't SSE or any other eightbyte isn't SSEUP, the whole
1478   //     argument is passed in memory. NOTE: This is necessary to keep the
1479   //     ABI working for processors that don't support the __m256 type.
1480   //
1481   // (d) If SSEUP is not preceded by SSE or SSEUP, it is converted to SSE.
1482   //
1483   // Some of these are enforced by the merging logic.  Others can arise
1484   // only with unions; for example:
1485   //   union { _Complex double; unsigned; }
1486   //
1487   // Note that clauses (b) and (c) were added in 0.98.
1488   //
1489   if (Hi == Memory)
1490     Lo = Memory;
1491   if (Hi == X87Up && Lo != X87 && honorsRevision0_98())
1492     Lo = Memory;
1493   if (AggregateSize > 128 && (Lo != SSE || Hi != SSEUp))
1494     Lo = Memory;
1495   if (Hi == SSEUp && Lo != SSE)
1496     Hi = SSE;
1497 }
1498 
1499 X86_64ABIInfo::Class X86_64ABIInfo::merge(Class Accum, Class Field) {
1500   // AMD64-ABI 3.2.3p2: Rule 4. Each field of an object is
1501   // classified recursively so that always two fields are
1502   // considered. The resulting class is calculated according to
1503   // the classes of the fields in the eightbyte:
1504   //
1505   // (a) If both classes are equal, this is the resulting class.
1506   //
1507   // (b) If one of the classes is NO_CLASS, the resulting class is
1508   // the other class.
1509   //
1510   // (c) If one of the classes is MEMORY, the result is the MEMORY
1511   // class.
1512   //
1513   // (d) If one of the classes is INTEGER, the result is the
1514   // INTEGER.
1515   //
1516   // (e) If one of the classes is X87, X87UP, COMPLEX_X87 class,
1517   // MEMORY is used as class.
1518   //
1519   // (f) Otherwise class SSE is used.
1520 
1521   // Accum should never be memory (we should have returned) or
1522   // ComplexX87 (because this cannot be passed in a structure).
1523   assert((Accum != Memory && Accum != ComplexX87) &&
1524          "Invalid accumulated classification during merge.");
1525   if (Accum == Field || Field == NoClass)
1526     return Accum;
1527   if (Field == Memory)
1528     return Memory;
1529   if (Accum == NoClass)
1530     return Field;
1531   if (Accum == Integer || Field == Integer)
1532     return Integer;
1533   if (Field == X87 || Field == X87Up || Field == ComplexX87 ||
1534       Accum == X87 || Accum == X87Up)
1535     return Memory;
1536   return SSE;
1537 }
1538 
1539 void X86_64ABIInfo::classify(QualType Ty, uint64_t OffsetBase,
1540                              Class &Lo, Class &Hi, bool isNamedArg) const {
1541   // FIXME: This code can be simplified by introducing a simple value class for
1542   // Class pairs with appropriate constructor methods for the various
1543   // situations.
1544 
1545   // FIXME: Some of the split computations are wrong; unaligned vectors
1546   // shouldn't be passed in registers for example, so there is no chance they
1547   // can straddle an eightbyte. Verify & simplify.
1548 
1549   Lo = Hi = NoClass;
1550 
1551   Class &Current = OffsetBase < 64 ? Lo : Hi;
1552   Current = Memory;
1553 
1554   if (const BuiltinType *BT = Ty->getAs<BuiltinType>()) {
1555     BuiltinType::Kind k = BT->getKind();
1556 
1557     if (k == BuiltinType::Void) {
1558       Current = NoClass;
1559     } else if (k == BuiltinType::Int128 || k == BuiltinType::UInt128) {
1560       Lo = Integer;
1561       Hi = Integer;
1562     } else if (k >= BuiltinType::Bool && k <= BuiltinType::LongLong) {
1563       Current = Integer;
1564     } else if ((k == BuiltinType::Float || k == BuiltinType::Double) ||
1565                (k == BuiltinType::LongDouble &&
1566                 getTarget().getTriple().isOSNaCl())) {
1567       Current = SSE;
1568     } else if (k == BuiltinType::LongDouble) {
1569       Lo = X87;
1570       Hi = X87Up;
1571     }
1572     // FIXME: _Decimal32 and _Decimal64 are SSE.
1573     // FIXME: _float128 and _Decimal128 are (SSE, SSEUp).
1574     return;
1575   }
1576 
1577   if (const EnumType *ET = Ty->getAs<EnumType>()) {
1578     // Classify the underlying integer type.
1579     classify(ET->getDecl()->getIntegerType(), OffsetBase, Lo, Hi, isNamedArg);
1580     return;
1581   }
1582 
1583   if (Ty->hasPointerRepresentation()) {
1584     Current = Integer;
1585     return;
1586   }
1587 
1588   if (Ty->isMemberPointerType()) {
1589     if (Ty->isMemberFunctionPointerType() && Has64BitPointers)
1590       Lo = Hi = Integer;
1591     else
1592       Current = Integer;
1593     return;
1594   }
1595 
1596   if (const VectorType *VT = Ty->getAs<VectorType>()) {
1597     uint64_t Size = getContext().getTypeSize(VT);
1598     if (Size == 32) {
1599       // gcc passes all <4 x char>, <2 x short>, <1 x int>, <1 x
1600       // float> as integer.
1601       Current = Integer;
1602 
1603       // If this type crosses an eightbyte boundary, it should be
1604       // split.
1605       uint64_t EB_Real = (OffsetBase) / 64;
1606       uint64_t EB_Imag = (OffsetBase + Size - 1) / 64;
1607       if (EB_Real != EB_Imag)
1608         Hi = Lo;
1609     } else if (Size == 64) {
1610       // gcc passes <1 x double> in memory. :(
1611       if (VT->getElementType()->isSpecificBuiltinType(BuiltinType::Double))
1612         return;
1613 
1614       // gcc passes <1 x long long> as INTEGER.
1615       if (VT->getElementType()->isSpecificBuiltinType(BuiltinType::LongLong) ||
1616           VT->getElementType()->isSpecificBuiltinType(BuiltinType::ULongLong) ||
1617           VT->getElementType()->isSpecificBuiltinType(BuiltinType::Long) ||
1618           VT->getElementType()->isSpecificBuiltinType(BuiltinType::ULong))
1619         Current = Integer;
1620       else
1621         Current = SSE;
1622 
1623       // If this type crosses an eightbyte boundary, it should be
1624       // split.
1625       if (OffsetBase && OffsetBase != 64)
1626         Hi = Lo;
1627     } else if (Size == 128 || (HasAVX && isNamedArg && Size == 256)) {
1628       // Arguments of 256-bits are split into four eightbyte chunks. The
1629       // least significant one belongs to class SSE and all the others to class
1630       // SSEUP. The original Lo and Hi design considers that types can't be
1631       // greater than 128-bits, so a 64-bit split in Hi and Lo makes sense.
1632       // This design isn't correct for 256-bits, but since there're no cases
1633       // where the upper parts would need to be inspected, avoid adding
1634       // complexity and just consider Hi to match the 64-256 part.
1635       //
1636       // Note that per 3.5.7 of AMD64-ABI, 256-bit args are only passed in
1637       // registers if they are "named", i.e. not part of the "..." of a
1638       // variadic function.
1639       Lo = SSE;
1640       Hi = SSEUp;
1641     }
1642     return;
1643   }
1644 
1645   if (const ComplexType *CT = Ty->getAs<ComplexType>()) {
1646     QualType ET = getContext().getCanonicalType(CT->getElementType());
1647 
1648     uint64_t Size = getContext().getTypeSize(Ty);
1649     if (ET->isIntegralOrEnumerationType()) {
1650       if (Size <= 64)
1651         Current = Integer;
1652       else if (Size <= 128)
1653         Lo = Hi = Integer;
1654     } else if (ET == getContext().FloatTy)
1655       Current = SSE;
1656     else if (ET == getContext().DoubleTy ||
1657              (ET == getContext().LongDoubleTy &&
1658               getTarget().getTriple().isOSNaCl()))
1659       Lo = Hi = SSE;
1660     else if (ET == getContext().LongDoubleTy)
1661       Current = ComplexX87;
1662 
1663     // If this complex type crosses an eightbyte boundary then it
1664     // should be split.
1665     uint64_t EB_Real = (OffsetBase) / 64;
1666     uint64_t EB_Imag = (OffsetBase + getContext().getTypeSize(ET)) / 64;
1667     if (Hi == NoClass && EB_Real != EB_Imag)
1668       Hi = Lo;
1669 
1670     return;
1671   }
1672 
1673   if (const ConstantArrayType *AT = getContext().getAsConstantArrayType(Ty)) {
1674     // Arrays are treated like structures.
1675 
1676     uint64_t Size = getContext().getTypeSize(Ty);
1677 
1678     // AMD64-ABI 3.2.3p2: Rule 1. If the size of an object is larger
1679     // than four eightbytes, ..., it has class MEMORY.
1680     if (Size > 256)
1681       return;
1682 
1683     // AMD64-ABI 3.2.3p2: Rule 1. If ..., or it contains unaligned
1684     // fields, it has class MEMORY.
1685     //
1686     // Only need to check alignment of array base.
1687     if (OffsetBase % getContext().getTypeAlign(AT->getElementType()))
1688       return;
1689 
1690     // Otherwise implement simplified merge. We could be smarter about
1691     // this, but it isn't worth it and would be harder to verify.
1692     Current = NoClass;
1693     uint64_t EltSize = getContext().getTypeSize(AT->getElementType());
1694     uint64_t ArraySize = AT->getSize().getZExtValue();
1695 
1696     // The only case a 256-bit wide vector could be used is when the array
1697     // contains a single 256-bit element. Since Lo and Hi logic isn't extended
1698     // to work for sizes wider than 128, early check and fallback to memory.
1699     if (Size > 128 && EltSize != 256)
1700       return;
1701 
1702     for (uint64_t i=0, Offset=OffsetBase; i<ArraySize; ++i, Offset += EltSize) {
1703       Class FieldLo, FieldHi;
1704       classify(AT->getElementType(), Offset, FieldLo, FieldHi, isNamedArg);
1705       Lo = merge(Lo, FieldLo);
1706       Hi = merge(Hi, FieldHi);
1707       if (Lo == Memory || Hi == Memory)
1708         break;
1709     }
1710 
1711     postMerge(Size, Lo, Hi);
1712     assert((Hi != SSEUp || Lo == SSE) && "Invalid SSEUp array classification.");
1713     return;
1714   }
1715 
1716   if (const RecordType *RT = Ty->getAs<RecordType>()) {
1717     uint64_t Size = getContext().getTypeSize(Ty);
1718 
1719     // AMD64-ABI 3.2.3p2: Rule 1. If the size of an object is larger
1720     // than four eightbytes, ..., it has class MEMORY.
1721     if (Size > 256)
1722       return;
1723 
1724     // AMD64-ABI 3.2.3p2: Rule 2. If a C++ object has either a non-trivial
1725     // copy constructor or a non-trivial destructor, it is passed by invisible
1726     // reference.
1727     if (getRecordArgABI(RT, getCXXABI()))
1728       return;
1729 
1730     const RecordDecl *RD = RT->getDecl();
1731 
1732     // Assume variable sized types are passed in memory.
1733     if (RD->hasFlexibleArrayMember())
1734       return;
1735 
1736     const ASTRecordLayout &Layout = getContext().getASTRecordLayout(RD);
1737 
1738     // Reset Lo class, this will be recomputed.
1739     Current = NoClass;
1740 
1741     // If this is a C++ record, classify the bases first.
1742     if (const CXXRecordDecl *CXXRD = dyn_cast<CXXRecordDecl>(RD)) {
1743       for (const auto &I : CXXRD->bases()) {
1744         assert(!I.isVirtual() && !I.getType()->isDependentType() &&
1745                "Unexpected base class!");
1746         const CXXRecordDecl *Base =
1747           cast<CXXRecordDecl>(I.getType()->getAs<RecordType>()->getDecl());
1748 
1749         // Classify this field.
1750         //
1751         // AMD64-ABI 3.2.3p2: Rule 3. If the size of the aggregate exceeds a
1752         // single eightbyte, each is classified separately. Each eightbyte gets
1753         // initialized to class NO_CLASS.
1754         Class FieldLo, FieldHi;
1755         uint64_t Offset =
1756           OffsetBase + getContext().toBits(Layout.getBaseClassOffset(Base));
1757         classify(I.getType(), Offset, FieldLo, FieldHi, isNamedArg);
1758         Lo = merge(Lo, FieldLo);
1759         Hi = merge(Hi, FieldHi);
1760         if (Lo == Memory || Hi == Memory)
1761           break;
1762       }
1763     }
1764 
1765     // Classify the fields one at a time, merging the results.
1766     unsigned idx = 0;
1767     for (RecordDecl::field_iterator i = RD->field_begin(), e = RD->field_end();
1768            i != e; ++i, ++idx) {
1769       uint64_t Offset = OffsetBase + Layout.getFieldOffset(idx);
1770       bool BitField = i->isBitField();
1771 
1772       // AMD64-ABI 3.2.3p2: Rule 1. If the size of an object is larger than
1773       // four eightbytes, or it contains unaligned fields, it has class MEMORY.
1774       //
1775       // The only case a 256-bit wide vector could be used is when the struct
1776       // contains a single 256-bit element. Since Lo and Hi logic isn't extended
1777       // to work for sizes wider than 128, early check and fallback to memory.
1778       //
1779       if (Size > 128 && getContext().getTypeSize(i->getType()) != 256) {
1780         Lo = Memory;
1781         return;
1782       }
1783       // Note, skip this test for bit-fields, see below.
1784       if (!BitField && Offset % getContext().getTypeAlign(i->getType())) {
1785         Lo = Memory;
1786         return;
1787       }
1788 
1789       // Classify this field.
1790       //
1791       // AMD64-ABI 3.2.3p2: Rule 3. If the size of the aggregate
1792       // exceeds a single eightbyte, each is classified
1793       // separately. Each eightbyte gets initialized to class
1794       // NO_CLASS.
1795       Class FieldLo, FieldHi;
1796 
1797       // Bit-fields require special handling, they do not force the
1798       // structure to be passed in memory even if unaligned, and
1799       // therefore they can straddle an eightbyte.
1800       if (BitField) {
1801         // Ignore padding bit-fields.
1802         if (i->isUnnamedBitfield())
1803           continue;
1804 
1805         uint64_t Offset = OffsetBase + Layout.getFieldOffset(idx);
1806         uint64_t Size = i->getBitWidthValue(getContext());
1807 
1808         uint64_t EB_Lo = Offset / 64;
1809         uint64_t EB_Hi = (Offset + Size - 1) / 64;
1810 
1811         if (EB_Lo) {
1812           assert(EB_Hi == EB_Lo && "Invalid classification, type > 16 bytes.");
1813           FieldLo = NoClass;
1814           FieldHi = Integer;
1815         } else {
1816           FieldLo = Integer;
1817           FieldHi = EB_Hi ? Integer : NoClass;
1818         }
1819       } else
1820         classify(i->getType(), Offset, FieldLo, FieldHi, isNamedArg);
1821       Lo = merge(Lo, FieldLo);
1822       Hi = merge(Hi, FieldHi);
1823       if (Lo == Memory || Hi == Memory)
1824         break;
1825     }
1826 
1827     postMerge(Size, Lo, Hi);
1828   }
1829 }
1830 
1831 ABIArgInfo X86_64ABIInfo::getIndirectReturnResult(QualType Ty) const {
1832   // If this is a scalar LLVM value then assume LLVM will pass it in the right
1833   // place naturally.
1834   if (!isAggregateTypeForABI(Ty)) {
1835     // Treat an enum type as its underlying type.
1836     if (const EnumType *EnumTy = Ty->getAs<EnumType>())
1837       Ty = EnumTy->getDecl()->getIntegerType();
1838 
1839     return (Ty->isPromotableIntegerType() ?
1840             ABIArgInfo::getExtend() : ABIArgInfo::getDirect());
1841   }
1842 
1843   return ABIArgInfo::getIndirect(0);
1844 }
1845 
1846 bool X86_64ABIInfo::IsIllegalVectorType(QualType Ty) const {
1847   if (const VectorType *VecTy = Ty->getAs<VectorType>()) {
1848     uint64_t Size = getContext().getTypeSize(VecTy);
1849     unsigned LargestVector = HasAVX ? 256 : 128;
1850     if (Size <= 64 || Size > LargestVector)
1851       return true;
1852   }
1853 
1854   return false;
1855 }
1856 
1857 ABIArgInfo X86_64ABIInfo::getIndirectResult(QualType Ty,
1858                                             unsigned freeIntRegs) const {
1859   // If this is a scalar LLVM value then assume LLVM will pass it in the right
1860   // place naturally.
1861   //
1862   // This assumption is optimistic, as there could be free registers available
1863   // when we need to pass this argument in memory, and LLVM could try to pass
1864   // the argument in the free register. This does not seem to happen currently,
1865   // but this code would be much safer if we could mark the argument with
1866   // 'onstack'. See PR12193.
1867   if (!isAggregateTypeForABI(Ty) && !IsIllegalVectorType(Ty)) {
1868     // Treat an enum type as its underlying type.
1869     if (const EnumType *EnumTy = Ty->getAs<EnumType>())
1870       Ty = EnumTy->getDecl()->getIntegerType();
1871 
1872     return (Ty->isPromotableIntegerType() ?
1873             ABIArgInfo::getExtend() : ABIArgInfo::getDirect());
1874   }
1875 
1876   if (CGCXXABI::RecordArgABI RAA = getRecordArgABI(Ty, getCXXABI()))
1877     return ABIArgInfo::getIndirect(0, RAA == CGCXXABI::RAA_DirectInMemory);
1878 
1879   // Compute the byval alignment. We specify the alignment of the byval in all
1880   // cases so that the mid-level optimizer knows the alignment of the byval.
1881   unsigned Align = std::max(getContext().getTypeAlign(Ty) / 8, 8U);
1882 
1883   // Attempt to avoid passing indirect results using byval when possible. This
1884   // is important for good codegen.
1885   //
1886   // We do this by coercing the value into a scalar type which the backend can
1887   // handle naturally (i.e., without using byval).
1888   //
1889   // For simplicity, we currently only do this when we have exhausted all of the
1890   // free integer registers. Doing this when there are free integer registers
1891   // would require more care, as we would have to ensure that the coerced value
1892   // did not claim the unused register. That would require either reording the
1893   // arguments to the function (so that any subsequent inreg values came first),
1894   // or only doing this optimization when there were no following arguments that
1895   // might be inreg.
1896   //
1897   // We currently expect it to be rare (particularly in well written code) for
1898   // arguments to be passed on the stack when there are still free integer
1899   // registers available (this would typically imply large structs being passed
1900   // by value), so this seems like a fair tradeoff for now.
1901   //
1902   // We can revisit this if the backend grows support for 'onstack' parameter
1903   // attributes. See PR12193.
1904   if (freeIntRegs == 0) {
1905     uint64_t Size = getContext().getTypeSize(Ty);
1906 
1907     // If this type fits in an eightbyte, coerce it into the matching integral
1908     // type, which will end up on the stack (with alignment 8).
1909     if (Align == 8 && Size <= 64)
1910       return ABIArgInfo::getDirect(llvm::IntegerType::get(getVMContext(),
1911                                                           Size));
1912   }
1913 
1914   return ABIArgInfo::getIndirect(Align);
1915 }
1916 
1917 /// GetByteVectorType - The ABI specifies that a value should be passed in an
1918 /// full vector XMM/YMM register.  Pick an LLVM IR type that will be passed as a
1919 /// vector register.
1920 llvm::Type *X86_64ABIInfo::GetByteVectorType(QualType Ty) const {
1921   llvm::Type *IRType = CGT.ConvertType(Ty);
1922 
1923   // Wrapper structs that just contain vectors are passed just like vectors,
1924   // strip them off if present.
1925   llvm::StructType *STy = dyn_cast<llvm::StructType>(IRType);
1926   while (STy && STy->getNumElements() == 1) {
1927     IRType = STy->getElementType(0);
1928     STy = dyn_cast<llvm::StructType>(IRType);
1929   }
1930 
1931   // If the preferred type is a 16-byte vector, prefer to pass it.
1932   if (llvm::VectorType *VT = dyn_cast<llvm::VectorType>(IRType)){
1933     llvm::Type *EltTy = VT->getElementType();
1934     unsigned BitWidth = VT->getBitWidth();
1935     if ((BitWidth >= 128 && BitWidth <= 256) &&
1936         (EltTy->isFloatTy() || EltTy->isDoubleTy() ||
1937          EltTy->isIntegerTy(8) || EltTy->isIntegerTy(16) ||
1938          EltTy->isIntegerTy(32) || EltTy->isIntegerTy(64) ||
1939          EltTy->isIntegerTy(128)))
1940       return VT;
1941   }
1942 
1943   return llvm::VectorType::get(llvm::Type::getDoubleTy(getVMContext()), 2);
1944 }
1945 
1946 /// BitsContainNoUserData - Return true if the specified [start,end) bit range
1947 /// is known to either be off the end of the specified type or being in
1948 /// alignment padding.  The user type specified is known to be at most 128 bits
1949 /// in size, and have passed through X86_64ABIInfo::classify with a successful
1950 /// classification that put one of the two halves in the INTEGER class.
1951 ///
1952 /// It is conservatively correct to return false.
1953 static bool BitsContainNoUserData(QualType Ty, unsigned StartBit,
1954                                   unsigned EndBit, ASTContext &Context) {
1955   // If the bytes being queried are off the end of the type, there is no user
1956   // data hiding here.  This handles analysis of builtins, vectors and other
1957   // types that don't contain interesting padding.
1958   unsigned TySize = (unsigned)Context.getTypeSize(Ty);
1959   if (TySize <= StartBit)
1960     return true;
1961 
1962   if (const ConstantArrayType *AT = Context.getAsConstantArrayType(Ty)) {
1963     unsigned EltSize = (unsigned)Context.getTypeSize(AT->getElementType());
1964     unsigned NumElts = (unsigned)AT->getSize().getZExtValue();
1965 
1966     // Check each element to see if the element overlaps with the queried range.
1967     for (unsigned i = 0; i != NumElts; ++i) {
1968       // If the element is after the span we care about, then we're done..
1969       unsigned EltOffset = i*EltSize;
1970       if (EltOffset >= EndBit) break;
1971 
1972       unsigned EltStart = EltOffset < StartBit ? StartBit-EltOffset :0;
1973       if (!BitsContainNoUserData(AT->getElementType(), EltStart,
1974                                  EndBit-EltOffset, Context))
1975         return false;
1976     }
1977     // If it overlaps no elements, then it is safe to process as padding.
1978     return true;
1979   }
1980 
1981   if (const RecordType *RT = Ty->getAs<RecordType>()) {
1982     const RecordDecl *RD = RT->getDecl();
1983     const ASTRecordLayout &Layout = Context.getASTRecordLayout(RD);
1984 
1985     // If this is a C++ record, check the bases first.
1986     if (const CXXRecordDecl *CXXRD = dyn_cast<CXXRecordDecl>(RD)) {
1987       for (const auto &I : CXXRD->bases()) {
1988         assert(!I.isVirtual() && !I.getType()->isDependentType() &&
1989                "Unexpected base class!");
1990         const CXXRecordDecl *Base =
1991           cast<CXXRecordDecl>(I.getType()->getAs<RecordType>()->getDecl());
1992 
1993         // If the base is after the span we care about, ignore it.
1994         unsigned BaseOffset = Context.toBits(Layout.getBaseClassOffset(Base));
1995         if (BaseOffset >= EndBit) continue;
1996 
1997         unsigned BaseStart = BaseOffset < StartBit ? StartBit-BaseOffset :0;
1998         if (!BitsContainNoUserData(I.getType(), BaseStart,
1999                                    EndBit-BaseOffset, Context))
2000           return false;
2001       }
2002     }
2003 
2004     // Verify that no field has data that overlaps the region of interest.  Yes
2005     // this could be sped up a lot by being smarter about queried fields,
2006     // however we're only looking at structs up to 16 bytes, so we don't care
2007     // much.
2008     unsigned idx = 0;
2009     for (RecordDecl::field_iterator i = RD->field_begin(), e = RD->field_end();
2010          i != e; ++i, ++idx) {
2011       unsigned FieldOffset = (unsigned)Layout.getFieldOffset(idx);
2012 
2013       // If we found a field after the region we care about, then we're done.
2014       if (FieldOffset >= EndBit) break;
2015 
2016       unsigned FieldStart = FieldOffset < StartBit ? StartBit-FieldOffset :0;
2017       if (!BitsContainNoUserData(i->getType(), FieldStart, EndBit-FieldOffset,
2018                                  Context))
2019         return false;
2020     }
2021 
2022     // If nothing in this record overlapped the area of interest, then we're
2023     // clean.
2024     return true;
2025   }
2026 
2027   return false;
2028 }
2029 
2030 /// ContainsFloatAtOffset - Return true if the specified LLVM IR type has a
2031 /// float member at the specified offset.  For example, {int,{float}} has a
2032 /// float at offset 4.  It is conservatively correct for this routine to return
2033 /// false.
2034 static bool ContainsFloatAtOffset(llvm::Type *IRType, unsigned IROffset,
2035                                   const llvm::DataLayout &TD) {
2036   // Base case if we find a float.
2037   if (IROffset == 0 && IRType->isFloatTy())
2038     return true;
2039 
2040   // If this is a struct, recurse into the field at the specified offset.
2041   if (llvm::StructType *STy = dyn_cast<llvm::StructType>(IRType)) {
2042     const llvm::StructLayout *SL = TD.getStructLayout(STy);
2043     unsigned Elt = SL->getElementContainingOffset(IROffset);
2044     IROffset -= SL->getElementOffset(Elt);
2045     return ContainsFloatAtOffset(STy->getElementType(Elt), IROffset, TD);
2046   }
2047 
2048   // If this is an array, recurse into the field at the specified offset.
2049   if (llvm::ArrayType *ATy = dyn_cast<llvm::ArrayType>(IRType)) {
2050     llvm::Type *EltTy = ATy->getElementType();
2051     unsigned EltSize = TD.getTypeAllocSize(EltTy);
2052     IROffset -= IROffset/EltSize*EltSize;
2053     return ContainsFloatAtOffset(EltTy, IROffset, TD);
2054   }
2055 
2056   return false;
2057 }
2058 
2059 
2060 /// GetSSETypeAtOffset - Return a type that will be passed by the backend in the
2061 /// low 8 bytes of an XMM register, corresponding to the SSE class.
2062 llvm::Type *X86_64ABIInfo::
2063 GetSSETypeAtOffset(llvm::Type *IRType, unsigned IROffset,
2064                    QualType SourceTy, unsigned SourceOffset) const {
2065   // The only three choices we have are either double, <2 x float>, or float. We
2066   // pass as float if the last 4 bytes is just padding.  This happens for
2067   // structs that contain 3 floats.
2068   if (BitsContainNoUserData(SourceTy, SourceOffset*8+32,
2069                             SourceOffset*8+64, getContext()))
2070     return llvm::Type::getFloatTy(getVMContext());
2071 
2072   // We want to pass as <2 x float> if the LLVM IR type contains a float at
2073   // offset+0 and offset+4.  Walk the LLVM IR type to find out if this is the
2074   // case.
2075   if (ContainsFloatAtOffset(IRType, IROffset, getDataLayout()) &&
2076       ContainsFloatAtOffset(IRType, IROffset+4, getDataLayout()))
2077     return llvm::VectorType::get(llvm::Type::getFloatTy(getVMContext()), 2);
2078 
2079   return llvm::Type::getDoubleTy(getVMContext());
2080 }
2081 
2082 
2083 /// GetINTEGERTypeAtOffset - The ABI specifies that a value should be passed in
2084 /// an 8-byte GPR.  This means that we either have a scalar or we are talking
2085 /// about the high or low part of an up-to-16-byte struct.  This routine picks
2086 /// the best LLVM IR type to represent this, which may be i64 or may be anything
2087 /// else that the backend will pass in a GPR that works better (e.g. i8, %foo*,
2088 /// etc).
2089 ///
2090 /// PrefType is an LLVM IR type that corresponds to (part of) the IR type for
2091 /// the source type.  IROffset is an offset in bytes into the LLVM IR type that
2092 /// the 8-byte value references.  PrefType may be null.
2093 ///
2094 /// SourceTy is the source-level type for the entire argument.  SourceOffset is
2095 /// an offset into this that we're processing (which is always either 0 or 8).
2096 ///
2097 llvm::Type *X86_64ABIInfo::
2098 GetINTEGERTypeAtOffset(llvm::Type *IRType, unsigned IROffset,
2099                        QualType SourceTy, unsigned SourceOffset) const {
2100   // If we're dealing with an un-offset LLVM IR type, then it means that we're
2101   // returning an 8-byte unit starting with it.  See if we can safely use it.
2102   if (IROffset == 0) {
2103     // Pointers and int64's always fill the 8-byte unit.
2104     if ((isa<llvm::PointerType>(IRType) && Has64BitPointers) ||
2105         IRType->isIntegerTy(64))
2106       return IRType;
2107 
2108     // If we have a 1/2/4-byte integer, we can use it only if the rest of the
2109     // goodness in the source type is just tail padding.  This is allowed to
2110     // kick in for struct {double,int} on the int, but not on
2111     // struct{double,int,int} because we wouldn't return the second int.  We
2112     // have to do this analysis on the source type because we can't depend on
2113     // unions being lowered a specific way etc.
2114     if (IRType->isIntegerTy(8) || IRType->isIntegerTy(16) ||
2115         IRType->isIntegerTy(32) ||
2116         (isa<llvm::PointerType>(IRType) && !Has64BitPointers)) {
2117       unsigned BitWidth = isa<llvm::PointerType>(IRType) ? 32 :
2118           cast<llvm::IntegerType>(IRType)->getBitWidth();
2119 
2120       if (BitsContainNoUserData(SourceTy, SourceOffset*8+BitWidth,
2121                                 SourceOffset*8+64, getContext()))
2122         return IRType;
2123     }
2124   }
2125 
2126   if (llvm::StructType *STy = dyn_cast<llvm::StructType>(IRType)) {
2127     // If this is a struct, recurse into the field at the specified offset.
2128     const llvm::StructLayout *SL = getDataLayout().getStructLayout(STy);
2129     if (IROffset < SL->getSizeInBytes()) {
2130       unsigned FieldIdx = SL->getElementContainingOffset(IROffset);
2131       IROffset -= SL->getElementOffset(FieldIdx);
2132 
2133       return GetINTEGERTypeAtOffset(STy->getElementType(FieldIdx), IROffset,
2134                                     SourceTy, SourceOffset);
2135     }
2136   }
2137 
2138   if (llvm::ArrayType *ATy = dyn_cast<llvm::ArrayType>(IRType)) {
2139     llvm::Type *EltTy = ATy->getElementType();
2140     unsigned EltSize = getDataLayout().getTypeAllocSize(EltTy);
2141     unsigned EltOffset = IROffset/EltSize*EltSize;
2142     return GetINTEGERTypeAtOffset(EltTy, IROffset-EltOffset, SourceTy,
2143                                   SourceOffset);
2144   }
2145 
2146   // Okay, we don't have any better idea of what to pass, so we pass this in an
2147   // integer register that isn't too big to fit the rest of the struct.
2148   unsigned TySizeInBytes =
2149     (unsigned)getContext().getTypeSizeInChars(SourceTy).getQuantity();
2150 
2151   assert(TySizeInBytes != SourceOffset && "Empty field?");
2152 
2153   // It is always safe to classify this as an integer type up to i64 that
2154   // isn't larger than the structure.
2155   return llvm::IntegerType::get(getVMContext(),
2156                                 std::min(TySizeInBytes-SourceOffset, 8U)*8);
2157 }
2158 
2159 
2160 /// GetX86_64ByValArgumentPair - Given a high and low type that can ideally
2161 /// be used as elements of a two register pair to pass or return, return a
2162 /// first class aggregate to represent them.  For example, if the low part of
2163 /// a by-value argument should be passed as i32* and the high part as float,
2164 /// return {i32*, float}.
2165 static llvm::Type *
2166 GetX86_64ByValArgumentPair(llvm::Type *Lo, llvm::Type *Hi,
2167                            const llvm::DataLayout &TD) {
2168   // In order to correctly satisfy the ABI, we need to the high part to start
2169   // at offset 8.  If the high and low parts we inferred are both 4-byte types
2170   // (e.g. i32 and i32) then the resultant struct type ({i32,i32}) won't have
2171   // the second element at offset 8.  Check for this:
2172   unsigned LoSize = (unsigned)TD.getTypeAllocSize(Lo);
2173   unsigned HiAlign = TD.getABITypeAlignment(Hi);
2174   unsigned HiStart = llvm::DataLayout::RoundUpAlignment(LoSize, HiAlign);
2175   assert(HiStart != 0 && HiStart <= 8 && "Invalid x86-64 argument pair!");
2176 
2177   // To handle this, we have to increase the size of the low part so that the
2178   // second element will start at an 8 byte offset.  We can't increase the size
2179   // of the second element because it might make us access off the end of the
2180   // struct.
2181   if (HiStart != 8) {
2182     // There are only two sorts of types the ABI generation code can produce for
2183     // the low part of a pair that aren't 8 bytes in size: float or i8/i16/i32.
2184     // Promote these to a larger type.
2185     if (Lo->isFloatTy())
2186       Lo = llvm::Type::getDoubleTy(Lo->getContext());
2187     else {
2188       assert(Lo->isIntegerTy() && "Invalid/unknown lo type");
2189       Lo = llvm::Type::getInt64Ty(Lo->getContext());
2190     }
2191   }
2192 
2193   llvm::StructType *Result = llvm::StructType::get(Lo, Hi, NULL);
2194 
2195 
2196   // Verify that the second element is at an 8-byte offset.
2197   assert(TD.getStructLayout(Result)->getElementOffset(1) == 8 &&
2198          "Invalid x86-64 argument pair!");
2199   return Result;
2200 }
2201 
2202 ABIArgInfo X86_64ABIInfo::
2203 classifyReturnType(QualType RetTy) const {
2204   // AMD64-ABI 3.2.3p4: Rule 1. Classify the return type with the
2205   // classification algorithm.
2206   X86_64ABIInfo::Class Lo, Hi;
2207   classify(RetTy, 0, Lo, Hi, /*isNamedArg*/ true);
2208 
2209   // Check some invariants.
2210   assert((Hi != Memory || Lo == Memory) && "Invalid memory classification.");
2211   assert((Hi != SSEUp || Lo == SSE) && "Invalid SSEUp classification.");
2212 
2213   llvm::Type *ResType = nullptr;
2214   switch (Lo) {
2215   case NoClass:
2216     if (Hi == NoClass)
2217       return ABIArgInfo::getIgnore();
2218     // If the low part is just padding, it takes no register, leave ResType
2219     // null.
2220     assert((Hi == SSE || Hi == Integer || Hi == X87Up) &&
2221            "Unknown missing lo part");
2222     break;
2223 
2224   case SSEUp:
2225   case X87Up:
2226     llvm_unreachable("Invalid classification for lo word.");
2227 
2228     // AMD64-ABI 3.2.3p4: Rule 2. Types of class memory are returned via
2229     // hidden argument.
2230   case Memory:
2231     return getIndirectReturnResult(RetTy);
2232 
2233     // AMD64-ABI 3.2.3p4: Rule 3. If the class is INTEGER, the next
2234     // available register of the sequence %rax, %rdx is used.
2235   case Integer:
2236     ResType = GetINTEGERTypeAtOffset(CGT.ConvertType(RetTy), 0, RetTy, 0);
2237 
2238     // If we have a sign or zero extended integer, make sure to return Extend
2239     // so that the parameter gets the right LLVM IR attributes.
2240     if (Hi == NoClass && isa<llvm::IntegerType>(ResType)) {
2241       // Treat an enum type as its underlying type.
2242       if (const EnumType *EnumTy = RetTy->getAs<EnumType>())
2243         RetTy = EnumTy->getDecl()->getIntegerType();
2244 
2245       if (RetTy->isIntegralOrEnumerationType() &&
2246           RetTy->isPromotableIntegerType())
2247         return ABIArgInfo::getExtend();
2248     }
2249     break;
2250 
2251     // AMD64-ABI 3.2.3p4: Rule 4. If the class is SSE, the next
2252     // available SSE register of the sequence %xmm0, %xmm1 is used.
2253   case SSE:
2254     ResType = GetSSETypeAtOffset(CGT.ConvertType(RetTy), 0, RetTy, 0);
2255     break;
2256 
2257     // AMD64-ABI 3.2.3p4: Rule 6. If the class is X87, the value is
2258     // returned on the X87 stack in %st0 as 80-bit x87 number.
2259   case X87:
2260     ResType = llvm::Type::getX86_FP80Ty(getVMContext());
2261     break;
2262 
2263     // AMD64-ABI 3.2.3p4: Rule 8. If the class is COMPLEX_X87, the real
2264     // part of the value is returned in %st0 and the imaginary part in
2265     // %st1.
2266   case ComplexX87:
2267     assert(Hi == ComplexX87 && "Unexpected ComplexX87 classification.");
2268     ResType = llvm::StructType::get(llvm::Type::getX86_FP80Ty(getVMContext()),
2269                                     llvm::Type::getX86_FP80Ty(getVMContext()),
2270                                     NULL);
2271     break;
2272   }
2273 
2274   llvm::Type *HighPart = nullptr;
2275   switch (Hi) {
2276     // Memory was handled previously and X87 should
2277     // never occur as a hi class.
2278   case Memory:
2279   case X87:
2280     llvm_unreachable("Invalid classification for hi word.");
2281 
2282   case ComplexX87: // Previously handled.
2283   case NoClass:
2284     break;
2285 
2286   case Integer:
2287     HighPart = GetINTEGERTypeAtOffset(CGT.ConvertType(RetTy), 8, RetTy, 8);
2288     if (Lo == NoClass)  // Return HighPart at offset 8 in memory.
2289       return ABIArgInfo::getDirect(HighPart, 8);
2290     break;
2291   case SSE:
2292     HighPart = GetSSETypeAtOffset(CGT.ConvertType(RetTy), 8, RetTy, 8);
2293     if (Lo == NoClass)  // Return HighPart at offset 8 in memory.
2294       return ABIArgInfo::getDirect(HighPart, 8);
2295     break;
2296 
2297     // AMD64-ABI 3.2.3p4: Rule 5. If the class is SSEUP, the eightbyte
2298     // is passed in the next available eightbyte chunk if the last used
2299     // vector register.
2300     //
2301     // SSEUP should always be preceded by SSE, just widen.
2302   case SSEUp:
2303     assert(Lo == SSE && "Unexpected SSEUp classification.");
2304     ResType = GetByteVectorType(RetTy);
2305     break;
2306 
2307     // AMD64-ABI 3.2.3p4: Rule 7. If the class is X87UP, the value is
2308     // returned together with the previous X87 value in %st0.
2309   case X87Up:
2310     // If X87Up is preceded by X87, we don't need to do
2311     // anything. However, in some cases with unions it may not be
2312     // preceded by X87. In such situations we follow gcc and pass the
2313     // extra bits in an SSE reg.
2314     if (Lo != X87) {
2315       HighPart = GetSSETypeAtOffset(CGT.ConvertType(RetTy), 8, RetTy, 8);
2316       if (Lo == NoClass)  // Return HighPart at offset 8 in memory.
2317         return ABIArgInfo::getDirect(HighPart, 8);
2318     }
2319     break;
2320   }
2321 
2322   // If a high part was specified, merge it together with the low part.  It is
2323   // known to pass in the high eightbyte of the result.  We do this by forming a
2324   // first class struct aggregate with the high and low part: {low, high}
2325   if (HighPart)
2326     ResType = GetX86_64ByValArgumentPair(ResType, HighPart, getDataLayout());
2327 
2328   return ABIArgInfo::getDirect(ResType);
2329 }
2330 
2331 ABIArgInfo X86_64ABIInfo::classifyArgumentType(
2332   QualType Ty, unsigned freeIntRegs, unsigned &neededInt, unsigned &neededSSE,
2333   bool isNamedArg)
2334   const
2335 {
2336   X86_64ABIInfo::Class Lo, Hi;
2337   classify(Ty, 0, Lo, Hi, isNamedArg);
2338 
2339   // Check some invariants.
2340   // FIXME: Enforce these by construction.
2341   assert((Hi != Memory || Lo == Memory) && "Invalid memory classification.");
2342   assert((Hi != SSEUp || Lo == SSE) && "Invalid SSEUp classification.");
2343 
2344   neededInt = 0;
2345   neededSSE = 0;
2346   llvm::Type *ResType = nullptr;
2347   switch (Lo) {
2348   case NoClass:
2349     if (Hi == NoClass)
2350       return ABIArgInfo::getIgnore();
2351     // If the low part is just padding, it takes no register, leave ResType
2352     // null.
2353     assert((Hi == SSE || Hi == Integer || Hi == X87Up) &&
2354            "Unknown missing lo part");
2355     break;
2356 
2357     // AMD64-ABI 3.2.3p3: Rule 1. If the class is MEMORY, pass the argument
2358     // on the stack.
2359   case Memory:
2360 
2361     // AMD64-ABI 3.2.3p3: Rule 5. If the class is X87, X87UP or
2362     // COMPLEX_X87, it is passed in memory.
2363   case X87:
2364   case ComplexX87:
2365     if (getRecordArgABI(Ty, getCXXABI()) == CGCXXABI::RAA_Indirect)
2366       ++neededInt;
2367     return getIndirectResult(Ty, freeIntRegs);
2368 
2369   case SSEUp:
2370   case X87Up:
2371     llvm_unreachable("Invalid classification for lo word.");
2372 
2373     // AMD64-ABI 3.2.3p3: Rule 2. If the class is INTEGER, the next
2374     // available register of the sequence %rdi, %rsi, %rdx, %rcx, %r8
2375     // and %r9 is used.
2376   case Integer:
2377     ++neededInt;
2378 
2379     // Pick an 8-byte type based on the preferred type.
2380     ResType = GetINTEGERTypeAtOffset(CGT.ConvertType(Ty), 0, Ty, 0);
2381 
2382     // If we have a sign or zero extended integer, make sure to return Extend
2383     // so that the parameter gets the right LLVM IR attributes.
2384     if (Hi == NoClass && isa<llvm::IntegerType>(ResType)) {
2385       // Treat an enum type as its underlying type.
2386       if (const EnumType *EnumTy = Ty->getAs<EnumType>())
2387         Ty = EnumTy->getDecl()->getIntegerType();
2388 
2389       if (Ty->isIntegralOrEnumerationType() &&
2390           Ty->isPromotableIntegerType())
2391         return ABIArgInfo::getExtend();
2392     }
2393 
2394     break;
2395 
2396     // AMD64-ABI 3.2.3p3: Rule 3. If the class is SSE, the next
2397     // available SSE register is used, the registers are taken in the
2398     // order from %xmm0 to %xmm7.
2399   case SSE: {
2400     llvm::Type *IRType = CGT.ConvertType(Ty);
2401     ResType = GetSSETypeAtOffset(IRType, 0, Ty, 0);
2402     ++neededSSE;
2403     break;
2404   }
2405   }
2406 
2407   llvm::Type *HighPart = nullptr;
2408   switch (Hi) {
2409     // Memory was handled previously, ComplexX87 and X87 should
2410     // never occur as hi classes, and X87Up must be preceded by X87,
2411     // which is passed in memory.
2412   case Memory:
2413   case X87:
2414   case ComplexX87:
2415     llvm_unreachable("Invalid classification for hi word.");
2416 
2417   case NoClass: break;
2418 
2419   case Integer:
2420     ++neededInt;
2421     // Pick an 8-byte type based on the preferred type.
2422     HighPart = GetINTEGERTypeAtOffset(CGT.ConvertType(Ty), 8, Ty, 8);
2423 
2424     if (Lo == NoClass)  // Pass HighPart at offset 8 in memory.
2425       return ABIArgInfo::getDirect(HighPart, 8);
2426     break;
2427 
2428     // X87Up generally doesn't occur here (long double is passed in
2429     // memory), except in situations involving unions.
2430   case X87Up:
2431   case SSE:
2432     HighPart = GetSSETypeAtOffset(CGT.ConvertType(Ty), 8, Ty, 8);
2433 
2434     if (Lo == NoClass)  // Pass HighPart at offset 8 in memory.
2435       return ABIArgInfo::getDirect(HighPart, 8);
2436 
2437     ++neededSSE;
2438     break;
2439 
2440     // AMD64-ABI 3.2.3p3: Rule 4. If the class is SSEUP, the
2441     // eightbyte is passed in the upper half of the last used SSE
2442     // register.  This only happens when 128-bit vectors are passed.
2443   case SSEUp:
2444     assert(Lo == SSE && "Unexpected SSEUp classification");
2445     ResType = GetByteVectorType(Ty);
2446     break;
2447   }
2448 
2449   // If a high part was specified, merge it together with the low part.  It is
2450   // known to pass in the high eightbyte of the result.  We do this by forming a
2451   // first class struct aggregate with the high and low part: {low, high}
2452   if (HighPart)
2453     ResType = GetX86_64ByValArgumentPair(ResType, HighPart, getDataLayout());
2454 
2455   return ABIArgInfo::getDirect(ResType);
2456 }
2457 
2458 void X86_64ABIInfo::computeInfo(CGFunctionInfo &FI) const {
2459 
2460   if (!getCXXABI().classifyReturnType(FI))
2461     FI.getReturnInfo() = classifyReturnType(FI.getReturnType());
2462 
2463   // Keep track of the number of assigned registers.
2464   unsigned freeIntRegs = 6, freeSSERegs = 8;
2465 
2466   // If the return value is indirect, then the hidden argument is consuming one
2467   // integer register.
2468   if (FI.getReturnInfo().isIndirect())
2469     --freeIntRegs;
2470 
2471   bool isVariadic = FI.isVariadic();
2472   unsigned numRequiredArgs = 0;
2473   if (isVariadic)
2474     numRequiredArgs = FI.getRequiredArgs().getNumRequiredArgs();
2475 
2476   // AMD64-ABI 3.2.3p3: Once arguments are classified, the registers
2477   // get assigned (in left-to-right order) for passing as follows...
2478   for (CGFunctionInfo::arg_iterator it = FI.arg_begin(), ie = FI.arg_end();
2479        it != ie; ++it) {
2480     bool isNamedArg = true;
2481     if (isVariadic)
2482       isNamedArg = (it - FI.arg_begin()) <
2483                     static_cast<signed>(numRequiredArgs);
2484 
2485     unsigned neededInt, neededSSE;
2486     it->info = classifyArgumentType(it->type, freeIntRegs, neededInt,
2487                                     neededSSE, isNamedArg);
2488 
2489     // AMD64-ABI 3.2.3p3: If there are no registers available for any
2490     // eightbyte of an argument, the whole argument is passed on the
2491     // stack. If registers have already been assigned for some
2492     // eightbytes of such an argument, the assignments get reverted.
2493     if (freeIntRegs >= neededInt && freeSSERegs >= neededSSE) {
2494       freeIntRegs -= neededInt;
2495       freeSSERegs -= neededSSE;
2496     } else {
2497       it->info = getIndirectResult(it->type, freeIntRegs);
2498     }
2499   }
2500 }
2501 
2502 static llvm::Value *EmitVAArgFromMemory(llvm::Value *VAListAddr,
2503                                         QualType Ty,
2504                                         CodeGenFunction &CGF) {
2505   llvm::Value *overflow_arg_area_p =
2506     CGF.Builder.CreateStructGEP(VAListAddr, 2, "overflow_arg_area_p");
2507   llvm::Value *overflow_arg_area =
2508     CGF.Builder.CreateLoad(overflow_arg_area_p, "overflow_arg_area");
2509 
2510   // AMD64-ABI 3.5.7p5: Step 7. Align l->overflow_arg_area upwards to a 16
2511   // byte boundary if alignment needed by type exceeds 8 byte boundary.
2512   // It isn't stated explicitly in the standard, but in practice we use
2513   // alignment greater than 16 where necessary.
2514   uint64_t Align = CGF.getContext().getTypeAlign(Ty) / 8;
2515   if (Align > 8) {
2516     // overflow_arg_area = (overflow_arg_area + align - 1) & -align;
2517     llvm::Value *Offset =
2518       llvm::ConstantInt::get(CGF.Int64Ty, Align - 1);
2519     overflow_arg_area = CGF.Builder.CreateGEP(overflow_arg_area, Offset);
2520     llvm::Value *AsInt = CGF.Builder.CreatePtrToInt(overflow_arg_area,
2521                                                     CGF.Int64Ty);
2522     llvm::Value *Mask = llvm::ConstantInt::get(CGF.Int64Ty, -(uint64_t)Align);
2523     overflow_arg_area =
2524       CGF.Builder.CreateIntToPtr(CGF.Builder.CreateAnd(AsInt, Mask),
2525                                  overflow_arg_area->getType(),
2526                                  "overflow_arg_area.align");
2527   }
2528 
2529   // AMD64-ABI 3.5.7p5: Step 8. Fetch type from l->overflow_arg_area.
2530   llvm::Type *LTy = CGF.ConvertTypeForMem(Ty);
2531   llvm::Value *Res =
2532     CGF.Builder.CreateBitCast(overflow_arg_area,
2533                               llvm::PointerType::getUnqual(LTy));
2534 
2535   // AMD64-ABI 3.5.7p5: Step 9. Set l->overflow_arg_area to:
2536   // l->overflow_arg_area + sizeof(type).
2537   // AMD64-ABI 3.5.7p5: Step 10. Align l->overflow_arg_area upwards to
2538   // an 8 byte boundary.
2539 
2540   uint64_t SizeInBytes = (CGF.getContext().getTypeSize(Ty) + 7) / 8;
2541   llvm::Value *Offset =
2542       llvm::ConstantInt::get(CGF.Int32Ty, (SizeInBytes + 7)  & ~7);
2543   overflow_arg_area = CGF.Builder.CreateGEP(overflow_arg_area, Offset,
2544                                             "overflow_arg_area.next");
2545   CGF.Builder.CreateStore(overflow_arg_area, overflow_arg_area_p);
2546 
2547   // AMD64-ABI 3.5.7p5: Step 11. Return the fetched type.
2548   return Res;
2549 }
2550 
2551 llvm::Value *X86_64ABIInfo::EmitVAArg(llvm::Value *VAListAddr, QualType Ty,
2552                                       CodeGenFunction &CGF) const {
2553   // Assume that va_list type is correct; should be pointer to LLVM type:
2554   // struct {
2555   //   i32 gp_offset;
2556   //   i32 fp_offset;
2557   //   i8* overflow_arg_area;
2558   //   i8* reg_save_area;
2559   // };
2560   unsigned neededInt, neededSSE;
2561 
2562   Ty = CGF.getContext().getCanonicalType(Ty);
2563   ABIArgInfo AI = classifyArgumentType(Ty, 0, neededInt, neededSSE,
2564                                        /*isNamedArg*/false);
2565 
2566   // AMD64-ABI 3.5.7p5: Step 1. Determine whether type may be passed
2567   // in the registers. If not go to step 7.
2568   if (!neededInt && !neededSSE)
2569     return EmitVAArgFromMemory(VAListAddr, Ty, CGF);
2570 
2571   // AMD64-ABI 3.5.7p5: Step 2. Compute num_gp to hold the number of
2572   // general purpose registers needed to pass type and num_fp to hold
2573   // the number of floating point registers needed.
2574 
2575   // AMD64-ABI 3.5.7p5: Step 3. Verify whether arguments fit into
2576   // registers. In the case: l->gp_offset > 48 - num_gp * 8 or
2577   // l->fp_offset > 304 - num_fp * 16 go to step 7.
2578   //
2579   // NOTE: 304 is a typo, there are (6 * 8 + 8 * 16) = 176 bytes of
2580   // register save space).
2581 
2582   llvm::Value *InRegs = nullptr;
2583   llvm::Value *gp_offset_p = nullptr, *gp_offset = nullptr;
2584   llvm::Value *fp_offset_p = nullptr, *fp_offset = nullptr;
2585   if (neededInt) {
2586     gp_offset_p = CGF.Builder.CreateStructGEP(VAListAddr, 0, "gp_offset_p");
2587     gp_offset = CGF.Builder.CreateLoad(gp_offset_p, "gp_offset");
2588     InRegs = llvm::ConstantInt::get(CGF.Int32Ty, 48 - neededInt * 8);
2589     InRegs = CGF.Builder.CreateICmpULE(gp_offset, InRegs, "fits_in_gp");
2590   }
2591 
2592   if (neededSSE) {
2593     fp_offset_p = CGF.Builder.CreateStructGEP(VAListAddr, 1, "fp_offset_p");
2594     fp_offset = CGF.Builder.CreateLoad(fp_offset_p, "fp_offset");
2595     llvm::Value *FitsInFP =
2596       llvm::ConstantInt::get(CGF.Int32Ty, 176 - neededSSE * 16);
2597     FitsInFP = CGF.Builder.CreateICmpULE(fp_offset, FitsInFP, "fits_in_fp");
2598     InRegs = InRegs ? CGF.Builder.CreateAnd(InRegs, FitsInFP) : FitsInFP;
2599   }
2600 
2601   llvm::BasicBlock *InRegBlock = CGF.createBasicBlock("vaarg.in_reg");
2602   llvm::BasicBlock *InMemBlock = CGF.createBasicBlock("vaarg.in_mem");
2603   llvm::BasicBlock *ContBlock = CGF.createBasicBlock("vaarg.end");
2604   CGF.Builder.CreateCondBr(InRegs, InRegBlock, InMemBlock);
2605 
2606   // Emit code to load the value if it was passed in registers.
2607 
2608   CGF.EmitBlock(InRegBlock);
2609 
2610   // AMD64-ABI 3.5.7p5: Step 4. Fetch type from l->reg_save_area with
2611   // an offset of l->gp_offset and/or l->fp_offset. This may require
2612   // copying to a temporary location in case the parameter is passed
2613   // in different register classes or requires an alignment greater
2614   // than 8 for general purpose registers and 16 for XMM registers.
2615   //
2616   // FIXME: This really results in shameful code when we end up needing to
2617   // collect arguments from different places; often what should result in a
2618   // simple assembling of a structure from scattered addresses has many more
2619   // loads than necessary. Can we clean this up?
2620   llvm::Type *LTy = CGF.ConvertTypeForMem(Ty);
2621   llvm::Value *RegAddr =
2622     CGF.Builder.CreateLoad(CGF.Builder.CreateStructGEP(VAListAddr, 3),
2623                            "reg_save_area");
2624   if (neededInt && neededSSE) {
2625     // FIXME: Cleanup.
2626     assert(AI.isDirect() && "Unexpected ABI info for mixed regs");
2627     llvm::StructType *ST = cast<llvm::StructType>(AI.getCoerceToType());
2628     llvm::Value *Tmp = CGF.CreateMemTemp(Ty);
2629     Tmp = CGF.Builder.CreateBitCast(Tmp, ST->getPointerTo());
2630     assert(ST->getNumElements() == 2 && "Unexpected ABI info for mixed regs");
2631     llvm::Type *TyLo = ST->getElementType(0);
2632     llvm::Type *TyHi = ST->getElementType(1);
2633     assert((TyLo->isFPOrFPVectorTy() ^ TyHi->isFPOrFPVectorTy()) &&
2634            "Unexpected ABI info for mixed regs");
2635     llvm::Type *PTyLo = llvm::PointerType::getUnqual(TyLo);
2636     llvm::Type *PTyHi = llvm::PointerType::getUnqual(TyHi);
2637     llvm::Value *GPAddr = CGF.Builder.CreateGEP(RegAddr, gp_offset);
2638     llvm::Value *FPAddr = CGF.Builder.CreateGEP(RegAddr, fp_offset);
2639     llvm::Value *RegLoAddr = TyLo->isFPOrFPVectorTy() ? FPAddr : GPAddr;
2640     llvm::Value *RegHiAddr = TyLo->isFPOrFPVectorTy() ? GPAddr : FPAddr;
2641     llvm::Value *V =
2642       CGF.Builder.CreateLoad(CGF.Builder.CreateBitCast(RegLoAddr, PTyLo));
2643     CGF.Builder.CreateStore(V, CGF.Builder.CreateStructGEP(Tmp, 0));
2644     V = CGF.Builder.CreateLoad(CGF.Builder.CreateBitCast(RegHiAddr, PTyHi));
2645     CGF.Builder.CreateStore(V, CGF.Builder.CreateStructGEP(Tmp, 1));
2646 
2647     RegAddr = CGF.Builder.CreateBitCast(Tmp,
2648                                         llvm::PointerType::getUnqual(LTy));
2649   } else if (neededInt) {
2650     RegAddr = CGF.Builder.CreateGEP(RegAddr, gp_offset);
2651     RegAddr = CGF.Builder.CreateBitCast(RegAddr,
2652                                         llvm::PointerType::getUnqual(LTy));
2653 
2654     // Copy to a temporary if necessary to ensure the appropriate alignment.
2655     std::pair<CharUnits, CharUnits> SizeAlign =
2656         CGF.getContext().getTypeInfoInChars(Ty);
2657     uint64_t TySize = SizeAlign.first.getQuantity();
2658     unsigned TyAlign = SizeAlign.second.getQuantity();
2659     if (TyAlign > 8) {
2660       llvm::Value *Tmp = CGF.CreateMemTemp(Ty);
2661       CGF.Builder.CreateMemCpy(Tmp, RegAddr, TySize, 8, false);
2662       RegAddr = Tmp;
2663     }
2664   } else if (neededSSE == 1) {
2665     RegAddr = CGF.Builder.CreateGEP(RegAddr, fp_offset);
2666     RegAddr = CGF.Builder.CreateBitCast(RegAddr,
2667                                         llvm::PointerType::getUnqual(LTy));
2668   } else {
2669     assert(neededSSE == 2 && "Invalid number of needed registers!");
2670     // SSE registers are spaced 16 bytes apart in the register save
2671     // area, we need to collect the two eightbytes together.
2672     llvm::Value *RegAddrLo = CGF.Builder.CreateGEP(RegAddr, fp_offset);
2673     llvm::Value *RegAddrHi = CGF.Builder.CreateConstGEP1_32(RegAddrLo, 16);
2674     llvm::Type *DoubleTy = CGF.DoubleTy;
2675     llvm::Type *DblPtrTy =
2676       llvm::PointerType::getUnqual(DoubleTy);
2677     llvm::StructType *ST = llvm::StructType::get(DoubleTy, DoubleTy, NULL);
2678     llvm::Value *V, *Tmp = CGF.CreateMemTemp(Ty);
2679     Tmp = CGF.Builder.CreateBitCast(Tmp, ST->getPointerTo());
2680     V = CGF.Builder.CreateLoad(CGF.Builder.CreateBitCast(RegAddrLo,
2681                                                          DblPtrTy));
2682     CGF.Builder.CreateStore(V, CGF.Builder.CreateStructGEP(Tmp, 0));
2683     V = CGF.Builder.CreateLoad(CGF.Builder.CreateBitCast(RegAddrHi,
2684                                                          DblPtrTy));
2685     CGF.Builder.CreateStore(V, CGF.Builder.CreateStructGEP(Tmp, 1));
2686     RegAddr = CGF.Builder.CreateBitCast(Tmp,
2687                                         llvm::PointerType::getUnqual(LTy));
2688   }
2689 
2690   // AMD64-ABI 3.5.7p5: Step 5. Set:
2691   // l->gp_offset = l->gp_offset + num_gp * 8
2692   // l->fp_offset = l->fp_offset + num_fp * 16.
2693   if (neededInt) {
2694     llvm::Value *Offset = llvm::ConstantInt::get(CGF.Int32Ty, neededInt * 8);
2695     CGF.Builder.CreateStore(CGF.Builder.CreateAdd(gp_offset, Offset),
2696                             gp_offset_p);
2697   }
2698   if (neededSSE) {
2699     llvm::Value *Offset = llvm::ConstantInt::get(CGF.Int32Ty, neededSSE * 16);
2700     CGF.Builder.CreateStore(CGF.Builder.CreateAdd(fp_offset, Offset),
2701                             fp_offset_p);
2702   }
2703   CGF.EmitBranch(ContBlock);
2704 
2705   // Emit code to load the value if it was passed in memory.
2706 
2707   CGF.EmitBlock(InMemBlock);
2708   llvm::Value *MemAddr = EmitVAArgFromMemory(VAListAddr, Ty, CGF);
2709 
2710   // Return the appropriate result.
2711 
2712   CGF.EmitBlock(ContBlock);
2713   llvm::PHINode *ResAddr = CGF.Builder.CreatePHI(RegAddr->getType(), 2,
2714                                                  "vaarg.addr");
2715   ResAddr->addIncoming(RegAddr, InRegBlock);
2716   ResAddr->addIncoming(MemAddr, InMemBlock);
2717   return ResAddr;
2718 }
2719 
2720 ABIArgInfo WinX86_64ABIInfo::classify(QualType Ty, bool IsReturnType) const {
2721 
2722   if (Ty->isVoidType())
2723     return ABIArgInfo::getIgnore();
2724 
2725   if (const EnumType *EnumTy = Ty->getAs<EnumType>())
2726     Ty = EnumTy->getDecl()->getIntegerType();
2727 
2728   uint64_t Size = getContext().getTypeSize(Ty);
2729 
2730   const RecordType *RT = Ty->getAs<RecordType>();
2731   if (RT) {
2732     if (!IsReturnType) {
2733       if (CGCXXABI::RecordArgABI RAA = getRecordArgABI(RT, getCXXABI()))
2734         return ABIArgInfo::getIndirect(0, RAA == CGCXXABI::RAA_DirectInMemory);
2735     }
2736 
2737     if (RT->getDecl()->hasFlexibleArrayMember())
2738       return ABIArgInfo::getIndirect(0, /*ByVal=*/false);
2739 
2740     // FIXME: mingw-w64-gcc emits 128-bit struct as i128
2741     if (Size == 128 && getTarget().getTriple().isWindowsGNUEnvironment())
2742       return ABIArgInfo::getDirect(llvm::IntegerType::get(getVMContext(),
2743                                                           Size));
2744   }
2745 
2746   if (Ty->isMemberPointerType()) {
2747     // If the member pointer is represented by an LLVM int or ptr, pass it
2748     // directly.
2749     llvm::Type *LLTy = CGT.ConvertType(Ty);
2750     if (LLTy->isPointerTy() || LLTy->isIntegerTy())
2751       return ABIArgInfo::getDirect();
2752   }
2753 
2754   if (RT || Ty->isMemberPointerType()) {
2755     // MS x64 ABI requirement: "Any argument that doesn't fit in 8 bytes, or is
2756     // not 1, 2, 4, or 8 bytes, must be passed by reference."
2757     if (Size > 64 || !llvm::isPowerOf2_64(Size))
2758       return ABIArgInfo::getIndirect(0, /*ByVal=*/false);
2759 
2760     // Otherwise, coerce it to a small integer.
2761     return ABIArgInfo::getDirect(llvm::IntegerType::get(getVMContext(), Size));
2762   }
2763 
2764   if (Ty->isPromotableIntegerType())
2765     return ABIArgInfo::getExtend();
2766 
2767   return ABIArgInfo::getDirect();
2768 }
2769 
2770 void WinX86_64ABIInfo::computeInfo(CGFunctionInfo &FI) const {
2771   if (!getCXXABI().classifyReturnType(FI))
2772     FI.getReturnInfo() = classify(FI.getReturnType(), true);
2773 
2774   for (auto &I : FI.arguments())
2775     I.info = classify(I.type, false);
2776 }
2777 
2778 llvm::Value *WinX86_64ABIInfo::EmitVAArg(llvm::Value *VAListAddr, QualType Ty,
2779                                       CodeGenFunction &CGF) const {
2780   llvm::Type *BPP = CGF.Int8PtrPtrTy;
2781 
2782   CGBuilderTy &Builder = CGF.Builder;
2783   llvm::Value *VAListAddrAsBPP = Builder.CreateBitCast(VAListAddr, BPP,
2784                                                        "ap");
2785   llvm::Value *Addr = Builder.CreateLoad(VAListAddrAsBPP, "ap.cur");
2786   llvm::Type *PTy =
2787     llvm::PointerType::getUnqual(CGF.ConvertType(Ty));
2788   llvm::Value *AddrTyped = Builder.CreateBitCast(Addr, PTy);
2789 
2790   uint64_t Offset =
2791     llvm::RoundUpToAlignment(CGF.getContext().getTypeSize(Ty) / 8, 8);
2792   llvm::Value *NextAddr =
2793     Builder.CreateGEP(Addr, llvm::ConstantInt::get(CGF.Int32Ty, Offset),
2794                       "ap.next");
2795   Builder.CreateStore(NextAddr, VAListAddrAsBPP);
2796 
2797   return AddrTyped;
2798 }
2799 
2800 namespace {
2801 
2802 class NaClX86_64ABIInfo : public ABIInfo {
2803  public:
2804   NaClX86_64ABIInfo(CodeGen::CodeGenTypes &CGT, bool HasAVX)
2805       : ABIInfo(CGT), PInfo(CGT), NInfo(CGT, HasAVX) {}
2806   void computeInfo(CGFunctionInfo &FI) const override;
2807   llvm::Value *EmitVAArg(llvm::Value *VAListAddr, QualType Ty,
2808                          CodeGenFunction &CGF) const override;
2809  private:
2810   PNaClABIInfo PInfo;  // Used for generating calls with pnaclcall callingconv.
2811   X86_64ABIInfo NInfo; // Used for everything else.
2812 };
2813 
2814 class NaClX86_64TargetCodeGenInfo : public TargetCodeGenInfo  {
2815  public:
2816   NaClX86_64TargetCodeGenInfo(CodeGen::CodeGenTypes &CGT, bool HasAVX)
2817       : TargetCodeGenInfo(new NaClX86_64ABIInfo(CGT, HasAVX)) {}
2818 };
2819 
2820 }
2821 
2822 void NaClX86_64ABIInfo::computeInfo(CGFunctionInfo &FI) const {
2823   if (FI.getASTCallingConvention() == CC_PnaclCall)
2824     PInfo.computeInfo(FI);
2825   else
2826     NInfo.computeInfo(FI);
2827 }
2828 
2829 llvm::Value *NaClX86_64ABIInfo::EmitVAArg(llvm::Value *VAListAddr, QualType Ty,
2830                                           CodeGenFunction &CGF) const {
2831   // Always use the native convention; calling pnacl-style varargs functions
2832   // is unuspported.
2833   return NInfo.EmitVAArg(VAListAddr, Ty, CGF);
2834 }
2835 
2836 
2837 // PowerPC-32
2838 
2839 namespace {
2840 class PPC32TargetCodeGenInfo : public DefaultTargetCodeGenInfo {
2841 public:
2842   PPC32TargetCodeGenInfo(CodeGenTypes &CGT) : DefaultTargetCodeGenInfo(CGT) {}
2843 
2844   int getDwarfEHStackPointer(CodeGen::CodeGenModule &M) const override {
2845     // This is recovered from gcc output.
2846     return 1; // r1 is the dedicated stack pointer
2847   }
2848 
2849   bool initDwarfEHRegSizeTable(CodeGen::CodeGenFunction &CGF,
2850                                llvm::Value *Address) const override;
2851 };
2852 
2853 }
2854 
2855 bool
2856 PPC32TargetCodeGenInfo::initDwarfEHRegSizeTable(CodeGen::CodeGenFunction &CGF,
2857                                                 llvm::Value *Address) const {
2858   // This is calculated from the LLVM and GCC tables and verified
2859   // against gcc output.  AFAIK all ABIs use the same encoding.
2860 
2861   CodeGen::CGBuilderTy &Builder = CGF.Builder;
2862 
2863   llvm::IntegerType *i8 = CGF.Int8Ty;
2864   llvm::Value *Four8 = llvm::ConstantInt::get(i8, 4);
2865   llvm::Value *Eight8 = llvm::ConstantInt::get(i8, 8);
2866   llvm::Value *Sixteen8 = llvm::ConstantInt::get(i8, 16);
2867 
2868   // 0-31: r0-31, the 4-byte general-purpose registers
2869   AssignToArrayRange(Builder, Address, Four8, 0, 31);
2870 
2871   // 32-63: fp0-31, the 8-byte floating-point registers
2872   AssignToArrayRange(Builder, Address, Eight8, 32, 63);
2873 
2874   // 64-76 are various 4-byte special-purpose registers:
2875   // 64: mq
2876   // 65: lr
2877   // 66: ctr
2878   // 67: ap
2879   // 68-75 cr0-7
2880   // 76: xer
2881   AssignToArrayRange(Builder, Address, Four8, 64, 76);
2882 
2883   // 77-108: v0-31, the 16-byte vector registers
2884   AssignToArrayRange(Builder, Address, Sixteen8, 77, 108);
2885 
2886   // 109: vrsave
2887   // 110: vscr
2888   // 111: spe_acc
2889   // 112: spefscr
2890   // 113: sfp
2891   AssignToArrayRange(Builder, Address, Four8, 109, 113);
2892 
2893   return false;
2894 }
2895 
2896 // PowerPC-64
2897 
2898 namespace {
2899 /// PPC64_SVR4_ABIInfo - The 64-bit PowerPC ELF (SVR4) ABI information.
2900 class PPC64_SVR4_ABIInfo : public DefaultABIInfo {
2901 
2902 public:
2903   PPC64_SVR4_ABIInfo(CodeGen::CodeGenTypes &CGT) : DefaultABIInfo(CGT) {}
2904 
2905   bool isPromotableTypeForABI(QualType Ty) const;
2906   bool isAlignedParamType(QualType Ty) const;
2907 
2908   ABIArgInfo classifyReturnType(QualType RetTy) const;
2909   ABIArgInfo classifyArgumentType(QualType Ty) const;
2910 
2911   // TODO: We can add more logic to computeInfo to improve performance.
2912   // Example: For aggregate arguments that fit in a register, we could
2913   // use getDirectInReg (as is done below for structs containing a single
2914   // floating-point value) to avoid pushing them to memory on function
2915   // entry.  This would require changing the logic in PPCISelLowering
2916   // when lowering the parameters in the caller and args in the callee.
2917   void computeInfo(CGFunctionInfo &FI) const override {
2918     if (!getCXXABI().classifyReturnType(FI))
2919       FI.getReturnInfo() = classifyReturnType(FI.getReturnType());
2920     for (auto &I : FI.arguments()) {
2921       // We rely on the default argument classification for the most part.
2922       // One exception:  An aggregate containing a single floating-point
2923       // or vector item must be passed in a register if one is available.
2924       const Type *T = isSingleElementStruct(I.type, getContext());
2925       if (T) {
2926         const BuiltinType *BT = T->getAs<BuiltinType>();
2927         if ((T->isVectorType() && getContext().getTypeSize(T) == 128) ||
2928             (BT && BT->isFloatingPoint())) {
2929           QualType QT(T, 0);
2930           I.info = ABIArgInfo::getDirectInReg(CGT.ConvertType(QT));
2931           continue;
2932         }
2933       }
2934       I.info = classifyArgumentType(I.type);
2935     }
2936   }
2937 
2938   llvm::Value *EmitVAArg(llvm::Value *VAListAddr, QualType Ty,
2939                          CodeGenFunction &CGF) const override;
2940 };
2941 
2942 class PPC64_SVR4_TargetCodeGenInfo : public TargetCodeGenInfo {
2943 public:
2944   PPC64_SVR4_TargetCodeGenInfo(CodeGenTypes &CGT)
2945     : TargetCodeGenInfo(new PPC64_SVR4_ABIInfo(CGT)) {}
2946 
2947   int getDwarfEHStackPointer(CodeGen::CodeGenModule &M) const override {
2948     // This is recovered from gcc output.
2949     return 1; // r1 is the dedicated stack pointer
2950   }
2951 
2952   bool initDwarfEHRegSizeTable(CodeGen::CodeGenFunction &CGF,
2953                                llvm::Value *Address) const override;
2954 };
2955 
2956 class PPC64TargetCodeGenInfo : public DefaultTargetCodeGenInfo {
2957 public:
2958   PPC64TargetCodeGenInfo(CodeGenTypes &CGT) : DefaultTargetCodeGenInfo(CGT) {}
2959 
2960   int getDwarfEHStackPointer(CodeGen::CodeGenModule &M) const override {
2961     // This is recovered from gcc output.
2962     return 1; // r1 is the dedicated stack pointer
2963   }
2964 
2965   bool initDwarfEHRegSizeTable(CodeGen::CodeGenFunction &CGF,
2966                                llvm::Value *Address) const override;
2967 };
2968 
2969 }
2970 
2971 // Return true if the ABI requires Ty to be passed sign- or zero-
2972 // extended to 64 bits.
2973 bool
2974 PPC64_SVR4_ABIInfo::isPromotableTypeForABI(QualType Ty) const {
2975   // Treat an enum type as its underlying type.
2976   if (const EnumType *EnumTy = Ty->getAs<EnumType>())
2977     Ty = EnumTy->getDecl()->getIntegerType();
2978 
2979   // Promotable integer types are required to be promoted by the ABI.
2980   if (Ty->isPromotableIntegerType())
2981     return true;
2982 
2983   // In addition to the usual promotable integer types, we also need to
2984   // extend all 32-bit types, since the ABI requires promotion to 64 bits.
2985   if (const BuiltinType *BT = Ty->getAs<BuiltinType>())
2986     switch (BT->getKind()) {
2987     case BuiltinType::Int:
2988     case BuiltinType::UInt:
2989       return true;
2990     default:
2991       break;
2992     }
2993 
2994   return false;
2995 }
2996 
2997 /// isAlignedParamType - Determine whether a type requires 16-byte
2998 /// alignment in the parameter area.
2999 bool
3000 PPC64_SVR4_ABIInfo::isAlignedParamType(QualType Ty) const {
3001   // Complex types are passed just like their elements.
3002   if (const ComplexType *CTy = Ty->getAs<ComplexType>())
3003     Ty = CTy->getElementType();
3004 
3005   // Only vector types of size 16 bytes need alignment (larger types are
3006   // passed via reference, smaller types are not aligned).
3007   if (Ty->isVectorType())
3008     return getContext().getTypeSize(Ty) == 128;
3009 
3010   // For single-element float/vector structs, we consider the whole type
3011   // to have the same alignment requirements as its single element.
3012   const Type *AlignAsType = nullptr;
3013   const Type *EltType = isSingleElementStruct(Ty, getContext());
3014   if (EltType) {
3015     const BuiltinType *BT = EltType->getAs<BuiltinType>();
3016     if ((EltType->isVectorType() &&
3017          getContext().getTypeSize(EltType) == 128) ||
3018         (BT && BT->isFloatingPoint()))
3019       AlignAsType = EltType;
3020   }
3021 
3022   // With special case aggregates, only vector base types need alignment.
3023   if (AlignAsType)
3024     return AlignAsType->isVectorType();
3025 
3026   // Otherwise, we only need alignment for any aggregate type that
3027   // has an alignment requirement of >= 16 bytes.
3028   if (isAggregateTypeForABI(Ty) && getContext().getTypeAlign(Ty) >= 128)
3029     return true;
3030 
3031   return false;
3032 }
3033 
3034 ABIArgInfo
3035 PPC64_SVR4_ABIInfo::classifyArgumentType(QualType Ty) const {
3036   if (Ty->isAnyComplexType())
3037     return ABIArgInfo::getDirect();
3038 
3039   // Non-Altivec vector types are passed in GPRs (smaller than 16 bytes)
3040   // or via reference (larger than 16 bytes).
3041   if (Ty->isVectorType()) {
3042     uint64_t Size = getContext().getTypeSize(Ty);
3043     if (Size > 128)
3044       return ABIArgInfo::getIndirect(0, /*ByVal=*/false);
3045     else if (Size < 128) {
3046       llvm::Type *CoerceTy = llvm::IntegerType::get(getVMContext(), Size);
3047       return ABIArgInfo::getDirect(CoerceTy);
3048     }
3049   }
3050 
3051   if (isAggregateTypeForABI(Ty)) {
3052     if (CGCXXABI::RecordArgABI RAA = getRecordArgABI(Ty, getCXXABI()))
3053       return ABIArgInfo::getIndirect(0, RAA == CGCXXABI::RAA_DirectInMemory);
3054 
3055     uint64_t ABIAlign = isAlignedParamType(Ty)? 16 : 8;
3056     uint64_t TyAlign = getContext().getTypeAlign(Ty) / 8;
3057     return ABIArgInfo::getIndirect(ABIAlign, /*ByVal=*/true,
3058                                    /*Realign=*/TyAlign > ABIAlign);
3059   }
3060 
3061   return (isPromotableTypeForABI(Ty) ?
3062           ABIArgInfo::getExtend() : ABIArgInfo::getDirect());
3063 }
3064 
3065 ABIArgInfo
3066 PPC64_SVR4_ABIInfo::classifyReturnType(QualType RetTy) const {
3067   if (RetTy->isVoidType())
3068     return ABIArgInfo::getIgnore();
3069 
3070   if (RetTy->isAnyComplexType())
3071     return ABIArgInfo::getDirect();
3072 
3073   // Non-Altivec vector types are returned in GPRs (smaller than 16 bytes)
3074   // or via reference (larger than 16 bytes).
3075   if (RetTy->isVectorType()) {
3076     uint64_t Size = getContext().getTypeSize(RetTy);
3077     if (Size > 128)
3078       return ABIArgInfo::getIndirect(0);
3079     else if (Size < 128) {
3080       llvm::Type *CoerceTy = llvm::IntegerType::get(getVMContext(), Size);
3081       return ABIArgInfo::getDirect(CoerceTy);
3082     }
3083   }
3084 
3085   if (isAggregateTypeForABI(RetTy))
3086     return ABIArgInfo::getIndirect(0);
3087 
3088   return (isPromotableTypeForABI(RetTy) ?
3089           ABIArgInfo::getExtend() : ABIArgInfo::getDirect());
3090 }
3091 
3092 // Based on ARMABIInfo::EmitVAArg, adjusted for 64-bit machine.
3093 llvm::Value *PPC64_SVR4_ABIInfo::EmitVAArg(llvm::Value *VAListAddr,
3094                                            QualType Ty,
3095                                            CodeGenFunction &CGF) const {
3096   llvm::Type *BP = CGF.Int8PtrTy;
3097   llvm::Type *BPP = CGF.Int8PtrPtrTy;
3098 
3099   CGBuilderTy &Builder = CGF.Builder;
3100   llvm::Value *VAListAddrAsBPP = Builder.CreateBitCast(VAListAddr, BPP, "ap");
3101   llvm::Value *Addr = Builder.CreateLoad(VAListAddrAsBPP, "ap.cur");
3102 
3103   // Handle types that require 16-byte alignment in the parameter save area.
3104   if (isAlignedParamType(Ty)) {
3105     llvm::Value *AddrAsInt = Builder.CreatePtrToInt(Addr, CGF.Int64Ty);
3106     AddrAsInt = Builder.CreateAdd(AddrAsInt, Builder.getInt64(15));
3107     AddrAsInt = Builder.CreateAnd(AddrAsInt, Builder.getInt64(-16));
3108     Addr = Builder.CreateIntToPtr(AddrAsInt, BP, "ap.align");
3109   }
3110 
3111   // Update the va_list pointer.  The pointer should be bumped by the
3112   // size of the object.  We can trust getTypeSize() except for a complex
3113   // type whose base type is smaller than a doubleword.  For these, the
3114   // size of the object is 16 bytes; see below for further explanation.
3115   unsigned SizeInBytes = CGF.getContext().getTypeSize(Ty) / 8;
3116   QualType BaseTy;
3117   unsigned CplxBaseSize = 0;
3118 
3119   if (const ComplexType *CTy = Ty->getAs<ComplexType>()) {
3120     BaseTy = CTy->getElementType();
3121     CplxBaseSize = CGF.getContext().getTypeSize(BaseTy) / 8;
3122     if (CplxBaseSize < 8)
3123       SizeInBytes = 16;
3124   }
3125 
3126   unsigned Offset = llvm::RoundUpToAlignment(SizeInBytes, 8);
3127   llvm::Value *NextAddr =
3128     Builder.CreateGEP(Addr, llvm::ConstantInt::get(CGF.Int64Ty, Offset),
3129                       "ap.next");
3130   Builder.CreateStore(NextAddr, VAListAddrAsBPP);
3131 
3132   // If we have a complex type and the base type is smaller than 8 bytes,
3133   // the ABI calls for the real and imaginary parts to be right-adjusted
3134   // in separate doublewords.  However, Clang expects us to produce a
3135   // pointer to a structure with the two parts packed tightly.  So generate
3136   // loads of the real and imaginary parts relative to the va_list pointer,
3137   // and store them to a temporary structure.
3138   if (CplxBaseSize && CplxBaseSize < 8) {
3139     llvm::Value *RealAddr = Builder.CreatePtrToInt(Addr, CGF.Int64Ty);
3140     llvm::Value *ImagAddr = RealAddr;
3141     if (CGF.CGM.getDataLayout().isBigEndian()) {
3142       RealAddr = Builder.CreateAdd(RealAddr, Builder.getInt64(8 - CplxBaseSize));
3143       ImagAddr = Builder.CreateAdd(ImagAddr, Builder.getInt64(16 - CplxBaseSize));
3144     } else {
3145       ImagAddr = Builder.CreateAdd(ImagAddr, Builder.getInt64(8));
3146     }
3147     llvm::Type *PBaseTy = llvm::PointerType::getUnqual(CGF.ConvertType(BaseTy));
3148     RealAddr = Builder.CreateIntToPtr(RealAddr, PBaseTy);
3149     ImagAddr = Builder.CreateIntToPtr(ImagAddr, PBaseTy);
3150     llvm::Value *Real = Builder.CreateLoad(RealAddr, false, ".vareal");
3151     llvm::Value *Imag = Builder.CreateLoad(ImagAddr, false, ".vaimag");
3152     llvm::Value *Ptr = CGF.CreateTempAlloca(CGT.ConvertTypeForMem(Ty),
3153                                             "vacplx");
3154     llvm::Value *RealPtr = Builder.CreateStructGEP(Ptr, 0, ".real");
3155     llvm::Value *ImagPtr = Builder.CreateStructGEP(Ptr, 1, ".imag");
3156     Builder.CreateStore(Real, RealPtr, false);
3157     Builder.CreateStore(Imag, ImagPtr, false);
3158     return Ptr;
3159   }
3160 
3161   // If the argument is smaller than 8 bytes, it is right-adjusted in
3162   // its doubleword slot.  Adjust the pointer to pick it up from the
3163   // correct offset.
3164   if (SizeInBytes < 8 && CGF.CGM.getDataLayout().isBigEndian()) {
3165     llvm::Value *AddrAsInt = Builder.CreatePtrToInt(Addr, CGF.Int64Ty);
3166     AddrAsInt = Builder.CreateAdd(AddrAsInt, Builder.getInt64(8 - SizeInBytes));
3167     Addr = Builder.CreateIntToPtr(AddrAsInt, BP);
3168   }
3169 
3170   llvm::Type *PTy = llvm::PointerType::getUnqual(CGF.ConvertType(Ty));
3171   return Builder.CreateBitCast(Addr, PTy);
3172 }
3173 
3174 static bool
3175 PPC64_initDwarfEHRegSizeTable(CodeGen::CodeGenFunction &CGF,
3176                               llvm::Value *Address) {
3177   // This is calculated from the LLVM and GCC tables and verified
3178   // against gcc output.  AFAIK all ABIs use the same encoding.
3179 
3180   CodeGen::CGBuilderTy &Builder = CGF.Builder;
3181 
3182   llvm::IntegerType *i8 = CGF.Int8Ty;
3183   llvm::Value *Four8 = llvm::ConstantInt::get(i8, 4);
3184   llvm::Value *Eight8 = llvm::ConstantInt::get(i8, 8);
3185   llvm::Value *Sixteen8 = llvm::ConstantInt::get(i8, 16);
3186 
3187   // 0-31: r0-31, the 8-byte general-purpose registers
3188   AssignToArrayRange(Builder, Address, Eight8, 0, 31);
3189 
3190   // 32-63: fp0-31, the 8-byte floating-point registers
3191   AssignToArrayRange(Builder, Address, Eight8, 32, 63);
3192 
3193   // 64-76 are various 4-byte special-purpose registers:
3194   // 64: mq
3195   // 65: lr
3196   // 66: ctr
3197   // 67: ap
3198   // 68-75 cr0-7
3199   // 76: xer
3200   AssignToArrayRange(Builder, Address, Four8, 64, 76);
3201 
3202   // 77-108: v0-31, the 16-byte vector registers
3203   AssignToArrayRange(Builder, Address, Sixteen8, 77, 108);
3204 
3205   // 109: vrsave
3206   // 110: vscr
3207   // 111: spe_acc
3208   // 112: spefscr
3209   // 113: sfp
3210   AssignToArrayRange(Builder, Address, Four8, 109, 113);
3211 
3212   return false;
3213 }
3214 
3215 bool
3216 PPC64_SVR4_TargetCodeGenInfo::initDwarfEHRegSizeTable(
3217   CodeGen::CodeGenFunction &CGF,
3218   llvm::Value *Address) const {
3219 
3220   return PPC64_initDwarfEHRegSizeTable(CGF, Address);
3221 }
3222 
3223 bool
3224 PPC64TargetCodeGenInfo::initDwarfEHRegSizeTable(CodeGen::CodeGenFunction &CGF,
3225                                                 llvm::Value *Address) const {
3226 
3227   return PPC64_initDwarfEHRegSizeTable(CGF, Address);
3228 }
3229 
3230 //===----------------------------------------------------------------------===//
3231 // AArch64 ABI Implementation
3232 //===----------------------------------------------------------------------===//
3233 
3234 namespace {
3235 
3236 class AArch64ABIInfo : public ABIInfo {
3237 public:
3238   enum ABIKind {
3239     AAPCS = 0,
3240     DarwinPCS
3241   };
3242 
3243 private:
3244   ABIKind Kind;
3245 
3246 public:
3247   AArch64ABIInfo(CodeGenTypes &CGT, ABIKind Kind) : ABIInfo(CGT), Kind(Kind) {}
3248 
3249 private:
3250   ABIKind getABIKind() const { return Kind; }
3251   bool isDarwinPCS() const { return Kind == DarwinPCS; }
3252 
3253   ABIArgInfo classifyReturnType(QualType RetTy) const;
3254   ABIArgInfo classifyArgumentType(QualType RetTy, unsigned &AllocatedVFP,
3255                                   bool &IsHA, unsigned &AllocatedGPR,
3256                                   bool &IsSmallAggr, bool IsNamedArg) const;
3257   bool isIllegalVectorType(QualType Ty) const;
3258 
3259   virtual void computeInfo(CGFunctionInfo &FI) const {
3260     // To correctly handle Homogeneous Aggregate, we need to keep track of the
3261     // number of SIMD and Floating-point registers allocated so far.
3262     // If the argument is an HFA or an HVA and there are sufficient unallocated
3263     // SIMD and Floating-point registers, then the argument is allocated to SIMD
3264     // and Floating-point Registers (with one register per member of the HFA or
3265     // HVA). Otherwise, the NSRN is set to 8.
3266     unsigned AllocatedVFP = 0;
3267 
3268     // To correctly handle small aggregates, we need to keep track of the number
3269     // of GPRs allocated so far. If the small aggregate can't all fit into
3270     // registers, it will be on stack. We don't allow the aggregate to be
3271     // partially in registers.
3272     unsigned AllocatedGPR = 0;
3273 
3274     // Find the number of named arguments. Variadic arguments get special
3275     // treatment with the Darwin ABI.
3276     unsigned NumRequiredArgs = (FI.isVariadic() ?
3277                                 FI.getRequiredArgs().getNumRequiredArgs() :
3278                                 FI.arg_size());
3279 
3280     if (!getCXXABI().classifyReturnType(FI))
3281       FI.getReturnInfo() = classifyReturnType(FI.getReturnType());
3282     for (CGFunctionInfo::arg_iterator it = FI.arg_begin(), ie = FI.arg_end();
3283          it != ie; ++it) {
3284       unsigned PreAllocation = AllocatedVFP, PreGPR = AllocatedGPR;
3285       bool IsHA = false, IsSmallAggr = false;
3286       const unsigned NumVFPs = 8;
3287       const unsigned NumGPRs = 8;
3288       bool IsNamedArg = ((it - FI.arg_begin()) <
3289                          static_cast<signed>(NumRequiredArgs));
3290       it->info = classifyArgumentType(it->type, AllocatedVFP, IsHA,
3291                                       AllocatedGPR, IsSmallAggr, IsNamedArg);
3292 
3293       // Under AAPCS the 64-bit stack slot alignment means we can't pass HAs
3294       // as sequences of floats since they'll get "holes" inserted as
3295       // padding by the back end.
3296       if (IsHA && AllocatedVFP > NumVFPs && !isDarwinPCS() &&
3297           getContext().getTypeAlign(it->type) < 64) {
3298         uint32_t NumStackSlots = getContext().getTypeSize(it->type);
3299         NumStackSlots = llvm::RoundUpToAlignment(NumStackSlots, 64) / 64;
3300 
3301         llvm::Type *CoerceTy = llvm::ArrayType::get(
3302             llvm::Type::getDoubleTy(getVMContext()), NumStackSlots);
3303         it->info = ABIArgInfo::getDirect(CoerceTy);
3304       }
3305 
3306       // If we do not have enough VFP registers for the HA, any VFP registers
3307       // that are unallocated are marked as unavailable. To achieve this, we add
3308       // padding of (NumVFPs - PreAllocation) floats.
3309       if (IsHA && AllocatedVFP > NumVFPs && PreAllocation < NumVFPs) {
3310         llvm::Type *PaddingTy = llvm::ArrayType::get(
3311             llvm::Type::getFloatTy(getVMContext()), NumVFPs - PreAllocation);
3312         it->info.setPaddingType(PaddingTy);
3313       }
3314 
3315       // If we do not have enough GPRs for the small aggregate, any GPR regs
3316       // that are unallocated are marked as unavailable.
3317       if (IsSmallAggr && AllocatedGPR > NumGPRs && PreGPR < NumGPRs) {
3318         llvm::Type *PaddingTy = llvm::ArrayType::get(
3319             llvm::Type::getInt32Ty(getVMContext()), NumGPRs - PreGPR);
3320         it->info =
3321             ABIArgInfo::getDirect(it->info.getCoerceToType(), 0, PaddingTy);
3322       }
3323     }
3324   }
3325 
3326   llvm::Value *EmitDarwinVAArg(llvm::Value *VAListAddr, QualType Ty,
3327                                CodeGenFunction &CGF) const;
3328 
3329   llvm::Value *EmitAAPCSVAArg(llvm::Value *VAListAddr, QualType Ty,
3330                               CodeGenFunction &CGF) const;
3331 
3332   virtual llvm::Value *EmitVAArg(llvm::Value *VAListAddr, QualType Ty,
3333                                  CodeGenFunction &CGF) const {
3334     return isDarwinPCS() ? EmitDarwinVAArg(VAListAddr, Ty, CGF)
3335                          : EmitAAPCSVAArg(VAListAddr, Ty, CGF);
3336   }
3337 };
3338 
3339 class AArch64TargetCodeGenInfo : public TargetCodeGenInfo {
3340 public:
3341   AArch64TargetCodeGenInfo(CodeGenTypes &CGT, AArch64ABIInfo::ABIKind Kind)
3342       : TargetCodeGenInfo(new AArch64ABIInfo(CGT, Kind)) {}
3343 
3344   StringRef getARCRetainAutoreleasedReturnValueMarker() const {
3345     return "mov\tfp, fp\t\t; marker for objc_retainAutoreleaseReturnValue";
3346   }
3347 
3348   int getDwarfEHStackPointer(CodeGen::CodeGenModule &M) const { return 31; }
3349 
3350   virtual bool doesReturnSlotInterfereWithArgs() const { return false; }
3351 };
3352 }
3353 
3354 static bool isHomogeneousAggregate(QualType Ty, const Type *&Base,
3355                                    ASTContext &Context,
3356                                    uint64_t *HAMembers = nullptr);
3357 
3358 ABIArgInfo AArch64ABIInfo::classifyArgumentType(QualType Ty,
3359                                                 unsigned &AllocatedVFP,
3360                                                 bool &IsHA,
3361                                                 unsigned &AllocatedGPR,
3362                                                 bool &IsSmallAggr,
3363                                                 bool IsNamedArg) const {
3364   // Handle illegal vector types here.
3365   if (isIllegalVectorType(Ty)) {
3366     uint64_t Size = getContext().getTypeSize(Ty);
3367     if (Size <= 32) {
3368       llvm::Type *ResType = llvm::Type::getInt32Ty(getVMContext());
3369       AllocatedGPR++;
3370       return ABIArgInfo::getDirect(ResType);
3371     }
3372     if (Size == 64) {
3373       llvm::Type *ResType =
3374           llvm::VectorType::get(llvm::Type::getInt32Ty(getVMContext()), 2);
3375       AllocatedVFP++;
3376       return ABIArgInfo::getDirect(ResType);
3377     }
3378     if (Size == 128) {
3379       llvm::Type *ResType =
3380           llvm::VectorType::get(llvm::Type::getInt32Ty(getVMContext()), 4);
3381       AllocatedVFP++;
3382       return ABIArgInfo::getDirect(ResType);
3383     }
3384     AllocatedGPR++;
3385     return ABIArgInfo::getIndirect(0, /*ByVal=*/false);
3386   }
3387   if (Ty->isVectorType())
3388     // Size of a legal vector should be either 64 or 128.
3389     AllocatedVFP++;
3390   if (const BuiltinType *BT = Ty->getAs<BuiltinType>()) {
3391     if (BT->getKind() == BuiltinType::Half ||
3392         BT->getKind() == BuiltinType::Float ||
3393         BT->getKind() == BuiltinType::Double ||
3394         BT->getKind() == BuiltinType::LongDouble)
3395       AllocatedVFP++;
3396   }
3397 
3398   if (!isAggregateTypeForABI(Ty)) {
3399     // Treat an enum type as its underlying type.
3400     if (const EnumType *EnumTy = Ty->getAs<EnumType>())
3401       Ty = EnumTy->getDecl()->getIntegerType();
3402 
3403     if (!Ty->isFloatingType() && !Ty->isVectorType()) {
3404       unsigned Alignment = getContext().getTypeAlign(Ty);
3405       if (!isDarwinPCS() && Alignment > 64)
3406         AllocatedGPR = llvm::RoundUpToAlignment(AllocatedGPR, Alignment / 64);
3407 
3408       int RegsNeeded = getContext().getTypeSize(Ty) > 64 ? 2 : 1;
3409       AllocatedGPR += RegsNeeded;
3410     }
3411     return (Ty->isPromotableIntegerType() && isDarwinPCS()
3412                 ? ABIArgInfo::getExtend()
3413                 : ABIArgInfo::getDirect());
3414   }
3415 
3416   // Structures with either a non-trivial destructor or a non-trivial
3417   // copy constructor are always indirect.
3418   if (CGCXXABI::RecordArgABI RAA = getRecordArgABI(Ty, getCXXABI())) {
3419     AllocatedGPR++;
3420     return ABIArgInfo::getIndirect(0, /*ByVal=*/RAA ==
3421                                           CGCXXABI::RAA_DirectInMemory);
3422   }
3423 
3424   // Empty records are always ignored on Darwin, but actually passed in C++ mode
3425   // elsewhere for GNU compatibility.
3426   if (isEmptyRecord(getContext(), Ty, true)) {
3427     if (!getContext().getLangOpts().CPlusPlus || isDarwinPCS())
3428       return ABIArgInfo::getIgnore();
3429 
3430     ++AllocatedGPR;
3431     return ABIArgInfo::getDirect(llvm::Type::getInt8Ty(getVMContext()));
3432   }
3433 
3434   // Homogeneous Floating-point Aggregates (HFAs) need to be expanded.
3435   const Type *Base = nullptr;
3436   uint64_t Members = 0;
3437   if (isHomogeneousAggregate(Ty, Base, getContext(), &Members)) {
3438     IsHA = true;
3439     if (!IsNamedArg && isDarwinPCS()) {
3440       // With the Darwin ABI, variadic arguments are always passed on the stack
3441       // and should not be expanded. Treat variadic HFAs as arrays of doubles.
3442       uint64_t Size = getContext().getTypeSize(Ty);
3443       llvm::Type *BaseTy = llvm::Type::getDoubleTy(getVMContext());
3444       return ABIArgInfo::getDirect(llvm::ArrayType::get(BaseTy, Size / 64));
3445     }
3446     AllocatedVFP += Members;
3447     return ABIArgInfo::getExpand();
3448   }
3449 
3450   // Aggregates <= 16 bytes are passed directly in registers or on the stack.
3451   uint64_t Size = getContext().getTypeSize(Ty);
3452   if (Size <= 128) {
3453     unsigned Alignment = getContext().getTypeAlign(Ty);
3454     if (!isDarwinPCS() && Alignment > 64)
3455       AllocatedGPR = llvm::RoundUpToAlignment(AllocatedGPR, Alignment / 64);
3456 
3457     Size = 64 * ((Size + 63) / 64); // round up to multiple of 8 bytes
3458     AllocatedGPR += Size / 64;
3459     IsSmallAggr = true;
3460     // We use a pair of i64 for 16-byte aggregate with 8-byte alignment.
3461     // For aggregates with 16-byte alignment, we use i128.
3462     if (Alignment < 128 && Size == 128) {
3463       llvm::Type *BaseTy = llvm::Type::getInt64Ty(getVMContext());
3464       return ABIArgInfo::getDirect(llvm::ArrayType::get(BaseTy, Size / 64));
3465     }
3466     return ABIArgInfo::getDirect(llvm::IntegerType::get(getVMContext(), Size));
3467   }
3468 
3469   AllocatedGPR++;
3470   return ABIArgInfo::getIndirect(0, /*ByVal=*/false);
3471 }
3472 
3473 ABIArgInfo AArch64ABIInfo::classifyReturnType(QualType RetTy) const {
3474   if (RetTy->isVoidType())
3475     return ABIArgInfo::getIgnore();
3476 
3477   // Large vector types should be returned via memory.
3478   if (RetTy->isVectorType() && getContext().getTypeSize(RetTy) > 128)
3479     return ABIArgInfo::getIndirect(0);
3480 
3481   if (!isAggregateTypeForABI(RetTy)) {
3482     // Treat an enum type as its underlying type.
3483     if (const EnumType *EnumTy = RetTy->getAs<EnumType>())
3484       RetTy = EnumTy->getDecl()->getIntegerType();
3485 
3486     return (RetTy->isPromotableIntegerType() && isDarwinPCS()
3487                 ? ABIArgInfo::getExtend()
3488                 : ABIArgInfo::getDirect());
3489   }
3490 
3491   if (isEmptyRecord(getContext(), RetTy, true))
3492     return ABIArgInfo::getIgnore();
3493 
3494   const Type *Base = nullptr;
3495   if (isHomogeneousAggregate(RetTy, Base, getContext()))
3496     // Homogeneous Floating-point Aggregates (HFAs) are returned directly.
3497     return ABIArgInfo::getDirect();
3498 
3499   // Aggregates <= 16 bytes are returned directly in registers or on the stack.
3500   uint64_t Size = getContext().getTypeSize(RetTy);
3501   if (Size <= 128) {
3502     Size = 64 * ((Size + 63) / 64); // round up to multiple of 8 bytes
3503     return ABIArgInfo::getDirect(llvm::IntegerType::get(getVMContext(), Size));
3504   }
3505 
3506   return ABIArgInfo::getIndirect(0);
3507 }
3508 
3509 /// isIllegalVectorType - check whether the vector type is legal for AArch64.
3510 bool AArch64ABIInfo::isIllegalVectorType(QualType Ty) const {
3511   if (const VectorType *VT = Ty->getAs<VectorType>()) {
3512     // Check whether VT is legal.
3513     unsigned NumElements = VT->getNumElements();
3514     uint64_t Size = getContext().getTypeSize(VT);
3515     // NumElements should be power of 2 between 1 and 16.
3516     if ((NumElements & (NumElements - 1)) != 0 || NumElements > 16)
3517       return true;
3518     return Size != 64 && (Size != 128 || NumElements == 1);
3519   }
3520   return false;
3521 }
3522 
3523 static llvm::Value *EmitAArch64VAArg(llvm::Value *VAListAddr, QualType Ty,
3524                                      int AllocatedGPR, int AllocatedVFP,
3525                                      bool IsIndirect, CodeGenFunction &CGF) {
3526   // The AArch64 va_list type and handling is specified in the Procedure Call
3527   // Standard, section B.4:
3528   //
3529   // struct {
3530   //   void *__stack;
3531   //   void *__gr_top;
3532   //   void *__vr_top;
3533   //   int __gr_offs;
3534   //   int __vr_offs;
3535   // };
3536 
3537   llvm::BasicBlock *MaybeRegBlock = CGF.createBasicBlock("vaarg.maybe_reg");
3538   llvm::BasicBlock *InRegBlock = CGF.createBasicBlock("vaarg.in_reg");
3539   llvm::BasicBlock *OnStackBlock = CGF.createBasicBlock("vaarg.on_stack");
3540   llvm::BasicBlock *ContBlock = CGF.createBasicBlock("vaarg.end");
3541   auto &Ctx = CGF.getContext();
3542 
3543   llvm::Value *reg_offs_p = nullptr, *reg_offs = nullptr;
3544   int reg_top_index;
3545   int RegSize;
3546   if (AllocatedGPR) {
3547     assert(!AllocatedVFP && "Arguments never split between int & VFP regs");
3548     // 3 is the field number of __gr_offs
3549     reg_offs_p = CGF.Builder.CreateStructGEP(VAListAddr, 3, "gr_offs_p");
3550     reg_offs = CGF.Builder.CreateLoad(reg_offs_p, "gr_offs");
3551     reg_top_index = 1; // field number for __gr_top
3552     RegSize = 8 * AllocatedGPR;
3553   } else {
3554     assert(!AllocatedGPR && "Argument must go in VFP or int regs");
3555     // 4 is the field number of __vr_offs.
3556     reg_offs_p = CGF.Builder.CreateStructGEP(VAListAddr, 4, "vr_offs_p");
3557     reg_offs = CGF.Builder.CreateLoad(reg_offs_p, "vr_offs");
3558     reg_top_index = 2; // field number for __vr_top
3559     RegSize = 16 * AllocatedVFP;
3560   }
3561 
3562   //=======================================
3563   // Find out where argument was passed
3564   //=======================================
3565 
3566   // If reg_offs >= 0 we're already using the stack for this type of
3567   // argument. We don't want to keep updating reg_offs (in case it overflows,
3568   // though anyone passing 2GB of arguments, each at most 16 bytes, deserves
3569   // whatever they get).
3570   llvm::Value *UsingStack = nullptr;
3571   UsingStack = CGF.Builder.CreateICmpSGE(
3572       reg_offs, llvm::ConstantInt::get(CGF.Int32Ty, 0));
3573 
3574   CGF.Builder.CreateCondBr(UsingStack, OnStackBlock, MaybeRegBlock);
3575 
3576   // Otherwise, at least some kind of argument could go in these registers, the
3577   // question is whether this particular type is too big.
3578   CGF.EmitBlock(MaybeRegBlock);
3579 
3580   // Integer arguments may need to correct register alignment (for example a
3581   // "struct { __int128 a; };" gets passed in x_2N, x_{2N+1}). In this case we
3582   // align __gr_offs to calculate the potential address.
3583   if (AllocatedGPR && !IsIndirect && Ctx.getTypeAlign(Ty) > 64) {
3584     int Align = Ctx.getTypeAlign(Ty) / 8;
3585 
3586     reg_offs = CGF.Builder.CreateAdd(
3587         reg_offs, llvm::ConstantInt::get(CGF.Int32Ty, Align - 1),
3588         "align_regoffs");
3589     reg_offs = CGF.Builder.CreateAnd(
3590         reg_offs, llvm::ConstantInt::get(CGF.Int32Ty, -Align),
3591         "aligned_regoffs");
3592   }
3593 
3594   // Update the gr_offs/vr_offs pointer for next call to va_arg on this va_list.
3595   llvm::Value *NewOffset = nullptr;
3596   NewOffset = CGF.Builder.CreateAdd(
3597       reg_offs, llvm::ConstantInt::get(CGF.Int32Ty, RegSize), "new_reg_offs");
3598   CGF.Builder.CreateStore(NewOffset, reg_offs_p);
3599 
3600   // Now we're in a position to decide whether this argument really was in
3601   // registers or not.
3602   llvm::Value *InRegs = nullptr;
3603   InRegs = CGF.Builder.CreateICmpSLE(
3604       NewOffset, llvm::ConstantInt::get(CGF.Int32Ty, 0), "inreg");
3605 
3606   CGF.Builder.CreateCondBr(InRegs, InRegBlock, OnStackBlock);
3607 
3608   //=======================================
3609   // Argument was in registers
3610   //=======================================
3611 
3612   // Now we emit the code for if the argument was originally passed in
3613   // registers. First start the appropriate block:
3614   CGF.EmitBlock(InRegBlock);
3615 
3616   llvm::Value *reg_top_p = nullptr, *reg_top = nullptr;
3617   reg_top_p =
3618       CGF.Builder.CreateStructGEP(VAListAddr, reg_top_index, "reg_top_p");
3619   reg_top = CGF.Builder.CreateLoad(reg_top_p, "reg_top");
3620   llvm::Value *BaseAddr = CGF.Builder.CreateGEP(reg_top, reg_offs);
3621   llvm::Value *RegAddr = nullptr;
3622   llvm::Type *MemTy = llvm::PointerType::getUnqual(CGF.ConvertTypeForMem(Ty));
3623 
3624   if (IsIndirect) {
3625     // If it's been passed indirectly (actually a struct), whatever we find from
3626     // stored registers or on the stack will actually be a struct **.
3627     MemTy = llvm::PointerType::getUnqual(MemTy);
3628   }
3629 
3630   const Type *Base = nullptr;
3631   uint64_t NumMembers;
3632   bool IsHFA = isHomogeneousAggregate(Ty, Base, Ctx, &NumMembers);
3633   if (IsHFA && NumMembers > 1) {
3634     // Homogeneous aggregates passed in registers will have their elements split
3635     // and stored 16-bytes apart regardless of size (they're notionally in qN,
3636     // qN+1, ...). We reload and store into a temporary local variable
3637     // contiguously.
3638     assert(!IsIndirect && "Homogeneous aggregates should be passed directly");
3639     llvm::Type *BaseTy = CGF.ConvertType(QualType(Base, 0));
3640     llvm::Type *HFATy = llvm::ArrayType::get(BaseTy, NumMembers);
3641     llvm::Value *Tmp = CGF.CreateTempAlloca(HFATy);
3642     int Offset = 0;
3643 
3644     if (CGF.CGM.getDataLayout().isBigEndian() && Ctx.getTypeSize(Base) < 128)
3645       Offset = 16 - Ctx.getTypeSize(Base) / 8;
3646     for (unsigned i = 0; i < NumMembers; ++i) {
3647       llvm::Value *BaseOffset =
3648           llvm::ConstantInt::get(CGF.Int32Ty, 16 * i + Offset);
3649       llvm::Value *LoadAddr = CGF.Builder.CreateGEP(BaseAddr, BaseOffset);
3650       LoadAddr = CGF.Builder.CreateBitCast(
3651           LoadAddr, llvm::PointerType::getUnqual(BaseTy));
3652       llvm::Value *StoreAddr = CGF.Builder.CreateStructGEP(Tmp, i);
3653 
3654       llvm::Value *Elem = CGF.Builder.CreateLoad(LoadAddr);
3655       CGF.Builder.CreateStore(Elem, StoreAddr);
3656     }
3657 
3658     RegAddr = CGF.Builder.CreateBitCast(Tmp, MemTy);
3659   } else {
3660     // Otherwise the object is contiguous in memory
3661     unsigned BeAlign = reg_top_index == 2 ? 16 : 8;
3662     if (CGF.CGM.getDataLayout().isBigEndian() &&
3663         (IsHFA || !isAggregateTypeForABI(Ty)) &&
3664         Ctx.getTypeSize(Ty) < (BeAlign * 8)) {
3665       int Offset = BeAlign - Ctx.getTypeSize(Ty) / 8;
3666       BaseAddr = CGF.Builder.CreatePtrToInt(BaseAddr, CGF.Int64Ty);
3667 
3668       BaseAddr = CGF.Builder.CreateAdd(
3669           BaseAddr, llvm::ConstantInt::get(CGF.Int64Ty, Offset), "align_be");
3670 
3671       BaseAddr = CGF.Builder.CreateIntToPtr(BaseAddr, CGF.Int8PtrTy);
3672     }
3673 
3674     RegAddr = CGF.Builder.CreateBitCast(BaseAddr, MemTy);
3675   }
3676 
3677   CGF.EmitBranch(ContBlock);
3678 
3679   //=======================================
3680   // Argument was on the stack
3681   //=======================================
3682   CGF.EmitBlock(OnStackBlock);
3683 
3684   llvm::Value *stack_p = nullptr, *OnStackAddr = nullptr;
3685   stack_p = CGF.Builder.CreateStructGEP(VAListAddr, 0, "stack_p");
3686   OnStackAddr = CGF.Builder.CreateLoad(stack_p, "stack");
3687 
3688   // Again, stack arguments may need realigmnent. In this case both integer and
3689   // floating-point ones might be affected.
3690   if (!IsIndirect && Ctx.getTypeAlign(Ty) > 64) {
3691     int Align = Ctx.getTypeAlign(Ty) / 8;
3692 
3693     OnStackAddr = CGF.Builder.CreatePtrToInt(OnStackAddr, CGF.Int64Ty);
3694 
3695     OnStackAddr = CGF.Builder.CreateAdd(
3696         OnStackAddr, llvm::ConstantInt::get(CGF.Int64Ty, Align - 1),
3697         "align_stack");
3698     OnStackAddr = CGF.Builder.CreateAnd(
3699         OnStackAddr, llvm::ConstantInt::get(CGF.Int64Ty, -Align),
3700         "align_stack");
3701 
3702     OnStackAddr = CGF.Builder.CreateIntToPtr(OnStackAddr, CGF.Int8PtrTy);
3703   }
3704 
3705   uint64_t StackSize;
3706   if (IsIndirect)
3707     StackSize = 8;
3708   else
3709     StackSize = Ctx.getTypeSize(Ty) / 8;
3710 
3711   // All stack slots are 8 bytes
3712   StackSize = llvm::RoundUpToAlignment(StackSize, 8);
3713 
3714   llvm::Value *StackSizeC = llvm::ConstantInt::get(CGF.Int32Ty, StackSize);
3715   llvm::Value *NewStack =
3716       CGF.Builder.CreateGEP(OnStackAddr, StackSizeC, "new_stack");
3717 
3718   // Write the new value of __stack for the next call to va_arg
3719   CGF.Builder.CreateStore(NewStack, stack_p);
3720 
3721   if (CGF.CGM.getDataLayout().isBigEndian() && !isAggregateTypeForABI(Ty) &&
3722       Ctx.getTypeSize(Ty) < 64) {
3723     int Offset = 8 - Ctx.getTypeSize(Ty) / 8;
3724     OnStackAddr = CGF.Builder.CreatePtrToInt(OnStackAddr, CGF.Int64Ty);
3725 
3726     OnStackAddr = CGF.Builder.CreateAdd(
3727         OnStackAddr, llvm::ConstantInt::get(CGF.Int64Ty, Offset), "align_be");
3728 
3729     OnStackAddr = CGF.Builder.CreateIntToPtr(OnStackAddr, CGF.Int8PtrTy);
3730   }
3731 
3732   OnStackAddr = CGF.Builder.CreateBitCast(OnStackAddr, MemTy);
3733 
3734   CGF.EmitBranch(ContBlock);
3735 
3736   //=======================================
3737   // Tidy up
3738   //=======================================
3739   CGF.EmitBlock(ContBlock);
3740 
3741   llvm::PHINode *ResAddr = CGF.Builder.CreatePHI(MemTy, 2, "vaarg.addr");
3742   ResAddr->addIncoming(RegAddr, InRegBlock);
3743   ResAddr->addIncoming(OnStackAddr, OnStackBlock);
3744 
3745   if (IsIndirect)
3746     return CGF.Builder.CreateLoad(ResAddr, "vaarg.addr");
3747 
3748   return ResAddr;
3749 }
3750 
3751 llvm::Value *AArch64ABIInfo::EmitAAPCSVAArg(llvm::Value *VAListAddr, QualType Ty,
3752                                           CodeGenFunction &CGF) const {
3753 
3754   unsigned AllocatedGPR = 0, AllocatedVFP = 0;
3755   bool IsHA = false, IsSmallAggr = false;
3756   ABIArgInfo AI = classifyArgumentType(Ty, AllocatedVFP, IsHA, AllocatedGPR,
3757                                        IsSmallAggr, false /*IsNamedArg*/);
3758 
3759   return EmitAArch64VAArg(VAListAddr, Ty, AllocatedGPR, AllocatedVFP,
3760                           AI.isIndirect(), CGF);
3761 }
3762 
3763 llvm::Value *AArch64ABIInfo::EmitDarwinVAArg(llvm::Value *VAListAddr, QualType Ty,
3764                                            CodeGenFunction &CGF) const {
3765   // We do not support va_arg for aggregates or illegal vector types.
3766   // Lower VAArg here for these cases and use the LLVM va_arg instruction for
3767   // other cases.
3768   if (!isAggregateTypeForABI(Ty) && !isIllegalVectorType(Ty))
3769     return nullptr;
3770 
3771   uint64_t Size = CGF.getContext().getTypeSize(Ty) / 8;
3772   uint64_t Align = CGF.getContext().getTypeAlign(Ty) / 8;
3773 
3774   const Type *Base = nullptr;
3775   bool isHA = isHomogeneousAggregate(Ty, Base, getContext());
3776 
3777   bool isIndirect = false;
3778   // Arguments bigger than 16 bytes which aren't homogeneous aggregates should
3779   // be passed indirectly.
3780   if (Size > 16 && !isHA) {
3781     isIndirect = true;
3782     Size = 8;
3783     Align = 8;
3784   }
3785 
3786   llvm::Type *BP = llvm::Type::getInt8PtrTy(CGF.getLLVMContext());
3787   llvm::Type *BPP = llvm::PointerType::getUnqual(BP);
3788 
3789   CGBuilderTy &Builder = CGF.Builder;
3790   llvm::Value *VAListAddrAsBPP = Builder.CreateBitCast(VAListAddr, BPP, "ap");
3791   llvm::Value *Addr = Builder.CreateLoad(VAListAddrAsBPP, "ap.cur");
3792 
3793   if (isEmptyRecord(getContext(), Ty, true)) {
3794     // These are ignored for parameter passing purposes.
3795     llvm::Type *PTy = llvm::PointerType::getUnqual(CGF.ConvertType(Ty));
3796     return Builder.CreateBitCast(Addr, PTy);
3797   }
3798 
3799   const uint64_t MinABIAlign = 8;
3800   if (Align > MinABIAlign) {
3801     llvm::Value *Offset = llvm::ConstantInt::get(CGF.Int32Ty, Align - 1);
3802     Addr = Builder.CreateGEP(Addr, Offset);
3803     llvm::Value *AsInt = Builder.CreatePtrToInt(Addr, CGF.Int64Ty);
3804     llvm::Value *Mask = llvm::ConstantInt::get(CGF.Int64Ty, ~(Align - 1));
3805     llvm::Value *Aligned = Builder.CreateAnd(AsInt, Mask);
3806     Addr = Builder.CreateIntToPtr(Aligned, BP, "ap.align");
3807   }
3808 
3809   uint64_t Offset = llvm::RoundUpToAlignment(Size, MinABIAlign);
3810   llvm::Value *NextAddr = Builder.CreateGEP(
3811       Addr, llvm::ConstantInt::get(CGF.Int32Ty, Offset), "ap.next");
3812   Builder.CreateStore(NextAddr, VAListAddrAsBPP);
3813 
3814   if (isIndirect)
3815     Addr = Builder.CreateLoad(Builder.CreateBitCast(Addr, BPP));
3816   llvm::Type *PTy = llvm::PointerType::getUnqual(CGF.ConvertType(Ty));
3817   llvm::Value *AddrTyped = Builder.CreateBitCast(Addr, PTy);
3818 
3819   return AddrTyped;
3820 }
3821 
3822 //===----------------------------------------------------------------------===//
3823 // ARM ABI Implementation
3824 //===----------------------------------------------------------------------===//
3825 
3826 namespace {
3827 
3828 class ARMABIInfo : public ABIInfo {
3829 public:
3830   enum ABIKind {
3831     APCS = 0,
3832     AAPCS = 1,
3833     AAPCS_VFP
3834   };
3835 
3836 private:
3837   ABIKind Kind;
3838   mutable int VFPRegs[16];
3839   const unsigned NumVFPs;
3840   const unsigned NumGPRs;
3841   mutable unsigned AllocatedGPRs;
3842   mutable unsigned AllocatedVFPs;
3843 
3844 public:
3845   ARMABIInfo(CodeGenTypes &CGT, ABIKind _Kind) : ABIInfo(CGT), Kind(_Kind),
3846     NumVFPs(16), NumGPRs(4) {
3847     setRuntimeCC();
3848     resetAllocatedRegs();
3849   }
3850 
3851   bool isEABI() const {
3852     switch (getTarget().getTriple().getEnvironment()) {
3853     case llvm::Triple::Android:
3854     case llvm::Triple::EABI:
3855     case llvm::Triple::EABIHF:
3856     case llvm::Triple::GNUEABI:
3857     case llvm::Triple::GNUEABIHF:
3858       return true;
3859     default:
3860       return false;
3861     }
3862   }
3863 
3864   bool isEABIHF() const {
3865     switch (getTarget().getTriple().getEnvironment()) {
3866     case llvm::Triple::EABIHF:
3867     case llvm::Triple::GNUEABIHF:
3868       return true;
3869     default:
3870       return false;
3871     }
3872   }
3873 
3874   ABIKind getABIKind() const { return Kind; }
3875 
3876 private:
3877   ABIArgInfo classifyReturnType(QualType RetTy, bool isVariadic) const;
3878   ABIArgInfo classifyArgumentType(QualType RetTy, bool isVariadic,
3879                                   bool &IsCPRC) const;
3880   bool isIllegalVectorType(QualType Ty) const;
3881 
3882   void computeInfo(CGFunctionInfo &FI) const override;
3883 
3884   llvm::Value *EmitVAArg(llvm::Value *VAListAddr, QualType Ty,
3885                          CodeGenFunction &CGF) const override;
3886 
3887   llvm::CallingConv::ID getLLVMDefaultCC() const;
3888   llvm::CallingConv::ID getABIDefaultCC() const;
3889   void setRuntimeCC();
3890 
3891   void markAllocatedGPRs(unsigned Alignment, unsigned NumRequired) const;
3892   void markAllocatedVFPs(unsigned Alignment, unsigned NumRequired) const;
3893   void resetAllocatedRegs(void) const;
3894 };
3895 
3896 class ARMTargetCodeGenInfo : public TargetCodeGenInfo {
3897 public:
3898   ARMTargetCodeGenInfo(CodeGenTypes &CGT, ARMABIInfo::ABIKind K)
3899     :TargetCodeGenInfo(new ARMABIInfo(CGT, K)) {}
3900 
3901   const ARMABIInfo &getABIInfo() const {
3902     return static_cast<const ARMABIInfo&>(TargetCodeGenInfo::getABIInfo());
3903   }
3904 
3905   int getDwarfEHStackPointer(CodeGen::CodeGenModule &M) const override {
3906     return 13;
3907   }
3908 
3909   StringRef getARCRetainAutoreleasedReturnValueMarker() const override {
3910     return "mov\tr7, r7\t\t@ marker for objc_retainAutoreleaseReturnValue";
3911   }
3912 
3913   bool initDwarfEHRegSizeTable(CodeGen::CodeGenFunction &CGF,
3914                                llvm::Value *Address) const override {
3915     llvm::Value *Four8 = llvm::ConstantInt::get(CGF.Int8Ty, 4);
3916 
3917     // 0-15 are the 16 integer registers.
3918     AssignToArrayRange(CGF.Builder, Address, Four8, 0, 15);
3919     return false;
3920   }
3921 
3922   unsigned getSizeOfUnwindException() const override {
3923     if (getABIInfo().isEABI()) return 88;
3924     return TargetCodeGenInfo::getSizeOfUnwindException();
3925   }
3926 
3927   void SetTargetAttributes(const Decl *D, llvm::GlobalValue *GV,
3928                            CodeGen::CodeGenModule &CGM) const override {
3929     const FunctionDecl *FD = dyn_cast<FunctionDecl>(D);
3930     if (!FD)
3931       return;
3932 
3933     const ARMInterruptAttr *Attr = FD->getAttr<ARMInterruptAttr>();
3934     if (!Attr)
3935       return;
3936 
3937     const char *Kind;
3938     switch (Attr->getInterrupt()) {
3939     case ARMInterruptAttr::Generic: Kind = ""; break;
3940     case ARMInterruptAttr::IRQ:     Kind = "IRQ"; break;
3941     case ARMInterruptAttr::FIQ:     Kind = "FIQ"; break;
3942     case ARMInterruptAttr::SWI:     Kind = "SWI"; break;
3943     case ARMInterruptAttr::ABORT:   Kind = "ABORT"; break;
3944     case ARMInterruptAttr::UNDEF:   Kind = "UNDEF"; break;
3945     }
3946 
3947     llvm::Function *Fn = cast<llvm::Function>(GV);
3948 
3949     Fn->addFnAttr("interrupt", Kind);
3950 
3951     if (cast<ARMABIInfo>(getABIInfo()).getABIKind() == ARMABIInfo::APCS)
3952       return;
3953 
3954     // AAPCS guarantees that sp will be 8-byte aligned on any public interface,
3955     // however this is not necessarily true on taking any interrupt. Instruct
3956     // the backend to perform a realignment as part of the function prologue.
3957     llvm::AttrBuilder B;
3958     B.addStackAlignmentAttr(8);
3959     Fn->addAttributes(llvm::AttributeSet::FunctionIndex,
3960                       llvm::AttributeSet::get(CGM.getLLVMContext(),
3961                                               llvm::AttributeSet::FunctionIndex,
3962                                               B));
3963   }
3964 
3965 };
3966 
3967 }
3968 
3969 void ARMABIInfo::computeInfo(CGFunctionInfo &FI) const {
3970   // To correctly handle Homogeneous Aggregate, we need to keep track of the
3971   // VFP registers allocated so far.
3972   // C.1.vfp If the argument is a VFP CPRC and there are sufficient consecutive
3973   // VFP registers of the appropriate type unallocated then the argument is
3974   // allocated to the lowest-numbered sequence of such registers.
3975   // C.2.vfp If the argument is a VFP CPRC then any VFP registers that are
3976   // unallocated are marked as unavailable.
3977   resetAllocatedRegs();
3978 
3979   if (getCXXABI().classifyReturnType(FI)) {
3980     if (FI.getReturnInfo().isIndirect())
3981       markAllocatedGPRs(1, 1);
3982   } else {
3983     FI.getReturnInfo() = classifyReturnType(FI.getReturnType(), FI.isVariadic());
3984   }
3985   for (auto &I : FI.arguments()) {
3986     unsigned PreAllocationVFPs = AllocatedVFPs;
3987     unsigned PreAllocationGPRs = AllocatedGPRs;
3988     bool IsCPRC = false;
3989     // 6.1.2.3 There is one VFP co-processor register class using registers
3990     // s0-s15 (d0-d7) for passing arguments.
3991     I.info = classifyArgumentType(I.type, FI.isVariadic(), IsCPRC);
3992 
3993     // If we have allocated some arguments onto the stack (due to running
3994     // out of VFP registers), we cannot split an argument between GPRs and
3995     // the stack. If this situation occurs, we add padding to prevent the
3996     // GPRs from being used. In this situation, the current argument could
3997     // only be allocated by rule C.8, so rule C.6 would mark these GPRs as
3998     // unusable anyway.
3999     const bool StackUsed = PreAllocationGPRs > NumGPRs || PreAllocationVFPs > NumVFPs;
4000     if (!IsCPRC && PreAllocationGPRs < NumGPRs && AllocatedGPRs > NumGPRs && StackUsed) {
4001       llvm::Type *PaddingTy = llvm::ArrayType::get(
4002           llvm::Type::getInt32Ty(getVMContext()), NumGPRs - PreAllocationGPRs);
4003       if (I.info.canHaveCoerceToType()) {
4004         I.info = ABIArgInfo::getDirect(I.info.getCoerceToType() /* type */, 0 /* offset */,
4005                                        PaddingTy);
4006       } else {
4007         I.info = ABIArgInfo::getDirect(nullptr /* type */, 0 /* offset */,
4008                                        PaddingTy);
4009       }
4010     }
4011   }
4012 
4013   // Always honor user-specified calling convention.
4014   if (FI.getCallingConvention() != llvm::CallingConv::C)
4015     return;
4016 
4017   llvm::CallingConv::ID cc = getRuntimeCC();
4018   if (cc != llvm::CallingConv::C)
4019     FI.setEffectiveCallingConvention(cc);
4020 }
4021 
4022 /// Return the default calling convention that LLVM will use.
4023 llvm::CallingConv::ID ARMABIInfo::getLLVMDefaultCC() const {
4024   // The default calling convention that LLVM will infer.
4025   if (isEABIHF())
4026     return llvm::CallingConv::ARM_AAPCS_VFP;
4027   else if (isEABI())
4028     return llvm::CallingConv::ARM_AAPCS;
4029   else
4030     return llvm::CallingConv::ARM_APCS;
4031 }
4032 
4033 /// Return the calling convention that our ABI would like us to use
4034 /// as the C calling convention.
4035 llvm::CallingConv::ID ARMABIInfo::getABIDefaultCC() const {
4036   switch (getABIKind()) {
4037   case APCS: return llvm::CallingConv::ARM_APCS;
4038   case AAPCS: return llvm::CallingConv::ARM_AAPCS;
4039   case AAPCS_VFP: return llvm::CallingConv::ARM_AAPCS_VFP;
4040   }
4041   llvm_unreachable("bad ABI kind");
4042 }
4043 
4044 void ARMABIInfo::setRuntimeCC() {
4045   assert(getRuntimeCC() == llvm::CallingConv::C);
4046 
4047   // Don't muddy up the IR with a ton of explicit annotations if
4048   // they'd just match what LLVM will infer from the triple.
4049   llvm::CallingConv::ID abiCC = getABIDefaultCC();
4050   if (abiCC != getLLVMDefaultCC())
4051     RuntimeCC = abiCC;
4052 }
4053 
4054 /// isHomogeneousAggregate - Return true if a type is an AAPCS-VFP homogeneous
4055 /// aggregate.  If HAMembers is non-null, the number of base elements
4056 /// contained in the type is returned through it; this is used for the
4057 /// recursive calls that check aggregate component types.
4058 static bool isHomogeneousAggregate(QualType Ty, const Type *&Base,
4059                                    ASTContext &Context, uint64_t *HAMembers) {
4060   uint64_t Members = 0;
4061   if (const ConstantArrayType *AT = Context.getAsConstantArrayType(Ty)) {
4062     if (!isHomogeneousAggregate(AT->getElementType(), Base, Context, &Members))
4063       return false;
4064     Members *= AT->getSize().getZExtValue();
4065   } else if (const RecordType *RT = Ty->getAs<RecordType>()) {
4066     const RecordDecl *RD = RT->getDecl();
4067     if (RD->hasFlexibleArrayMember())
4068       return false;
4069 
4070     Members = 0;
4071     for (const auto *FD : RD->fields()) {
4072       uint64_t FldMembers;
4073       if (!isHomogeneousAggregate(FD->getType(), Base, Context, &FldMembers))
4074         return false;
4075 
4076       Members = (RD->isUnion() ?
4077                  std::max(Members, FldMembers) : Members + FldMembers);
4078     }
4079   } else {
4080     Members = 1;
4081     if (const ComplexType *CT = Ty->getAs<ComplexType>()) {
4082       Members = 2;
4083       Ty = CT->getElementType();
4084     }
4085 
4086     // Homogeneous aggregates for AAPCS-VFP must have base types of float,
4087     // double, or 64-bit or 128-bit vectors.
4088     if (const BuiltinType *BT = Ty->getAs<BuiltinType>()) {
4089       if (BT->getKind() != BuiltinType::Float &&
4090           BT->getKind() != BuiltinType::Double &&
4091           BT->getKind() != BuiltinType::LongDouble)
4092         return false;
4093     } else if (const VectorType *VT = Ty->getAs<VectorType>()) {
4094       unsigned VecSize = Context.getTypeSize(VT);
4095       if (VecSize != 64 && VecSize != 128)
4096         return false;
4097     } else {
4098       return false;
4099     }
4100 
4101     // The base type must be the same for all members.  Vector types of the
4102     // same total size are treated as being equivalent here.
4103     const Type *TyPtr = Ty.getTypePtr();
4104     if (!Base)
4105       Base = TyPtr;
4106 
4107     if (Base != TyPtr) {
4108       // Homogeneous aggregates are defined as containing members with the
4109       // same machine type. There are two cases in which two members have
4110       // different TypePtrs but the same machine type:
4111 
4112       // 1) Vectors of the same length, regardless of the type and number
4113       //    of their members.
4114       const bool SameLengthVectors = Base->isVectorType() && TyPtr->isVectorType()
4115         && (Context.getTypeSize(Base) == Context.getTypeSize(TyPtr));
4116 
4117       // 2) In the 32-bit AAPCS, `double' and `long double' have the same
4118       //    machine type. This is not the case for the 64-bit AAPCS.
4119       const bool SameSizeDoubles =
4120            (   (   Base->isSpecificBuiltinType(BuiltinType::Double)
4121                 && TyPtr->isSpecificBuiltinType(BuiltinType::LongDouble))
4122             || (   Base->isSpecificBuiltinType(BuiltinType::LongDouble)
4123                 && TyPtr->isSpecificBuiltinType(BuiltinType::Double)))
4124         && (Context.getTypeSize(Base) == Context.getTypeSize(TyPtr));
4125 
4126       if (!SameLengthVectors && !SameSizeDoubles)
4127         return false;
4128     }
4129   }
4130 
4131   // Homogeneous Aggregates can have at most 4 members of the base type.
4132   if (HAMembers)
4133     *HAMembers = Members;
4134 
4135   return (Members > 0 && Members <= 4);
4136 }
4137 
4138 /// markAllocatedVFPs - update VFPRegs according to the alignment and
4139 /// number of VFP registers (unit is S register) requested.
4140 void ARMABIInfo::markAllocatedVFPs(unsigned Alignment,
4141                                    unsigned NumRequired) const {
4142   // Early Exit.
4143   if (AllocatedVFPs >= 16) {
4144     // We use AllocatedVFP > 16 to signal that some CPRCs were allocated on
4145     // the stack.
4146     AllocatedVFPs = 17;
4147     return;
4148   }
4149   // C.1.vfp If the argument is a VFP CPRC and there are sufficient consecutive
4150   // VFP registers of the appropriate type unallocated then the argument is
4151   // allocated to the lowest-numbered sequence of such registers.
4152   for (unsigned I = 0; I < 16; I += Alignment) {
4153     bool FoundSlot = true;
4154     for (unsigned J = I, JEnd = I + NumRequired; J < JEnd; J++)
4155       if (J >= 16 || VFPRegs[J]) {
4156          FoundSlot = false;
4157          break;
4158       }
4159     if (FoundSlot) {
4160       for (unsigned J = I, JEnd = I + NumRequired; J < JEnd; J++)
4161         VFPRegs[J] = 1;
4162       AllocatedVFPs += NumRequired;
4163       return;
4164     }
4165   }
4166   // C.2.vfp If the argument is a VFP CPRC then any VFP registers that are
4167   // unallocated are marked as unavailable.
4168   for (unsigned I = 0; I < 16; I++)
4169     VFPRegs[I] = 1;
4170   AllocatedVFPs = 17; // We do not have enough VFP registers.
4171 }
4172 
4173 /// Update AllocatedGPRs to record the number of general purpose registers
4174 /// which have been allocated. It is valid for AllocatedGPRs to go above 4,
4175 /// this represents arguments being stored on the stack.
4176 void ARMABIInfo::markAllocatedGPRs(unsigned Alignment,
4177                                    unsigned NumRequired) const {
4178   assert((Alignment == 1 || Alignment == 2) && "Alignment must be 4 or 8 bytes");
4179 
4180   if (Alignment == 2 && AllocatedGPRs & 0x1)
4181     AllocatedGPRs += 1;
4182 
4183   AllocatedGPRs += NumRequired;
4184 }
4185 
4186 void ARMABIInfo::resetAllocatedRegs(void) const {
4187   AllocatedGPRs = 0;
4188   AllocatedVFPs = 0;
4189   for (unsigned i = 0; i < NumVFPs; ++i)
4190     VFPRegs[i] = 0;
4191 }
4192 
4193 ABIArgInfo ARMABIInfo::classifyArgumentType(QualType Ty, bool isVariadic,
4194                                             bool &IsCPRC) const {
4195   // We update number of allocated VFPs according to
4196   // 6.1.2.1 The following argument types are VFP CPRCs:
4197   //   A single-precision floating-point type (including promoted
4198   //   half-precision types); A double-precision floating-point type;
4199   //   A 64-bit or 128-bit containerized vector type; Homogeneous Aggregate
4200   //   with a Base Type of a single- or double-precision floating-point type,
4201   //   64-bit containerized vectors or 128-bit containerized vectors with one
4202   //   to four Elements.
4203 
4204   // Handle illegal vector types here.
4205   if (isIllegalVectorType(Ty)) {
4206     uint64_t Size = getContext().getTypeSize(Ty);
4207     if (Size <= 32) {
4208       llvm::Type *ResType =
4209           llvm::Type::getInt32Ty(getVMContext());
4210       markAllocatedGPRs(1, 1);
4211       return ABIArgInfo::getDirect(ResType);
4212     }
4213     if (Size == 64) {
4214       llvm::Type *ResType = llvm::VectorType::get(
4215           llvm::Type::getInt32Ty(getVMContext()), 2);
4216       if (getABIKind() == ARMABIInfo::AAPCS || isVariadic){
4217         markAllocatedGPRs(2, 2);
4218       } else {
4219         markAllocatedVFPs(2, 2);
4220         IsCPRC = true;
4221       }
4222       return ABIArgInfo::getDirect(ResType);
4223     }
4224     if (Size == 128) {
4225       llvm::Type *ResType = llvm::VectorType::get(
4226           llvm::Type::getInt32Ty(getVMContext()), 4);
4227       if (getABIKind() == ARMABIInfo::AAPCS || isVariadic) {
4228         markAllocatedGPRs(2, 4);
4229       } else {
4230         markAllocatedVFPs(4, 4);
4231         IsCPRC = true;
4232       }
4233       return ABIArgInfo::getDirect(ResType);
4234     }
4235     markAllocatedGPRs(1, 1);
4236     return ABIArgInfo::getIndirect(0, /*ByVal=*/false);
4237   }
4238   // Update VFPRegs for legal vector types.
4239   if (getABIKind() == ARMABIInfo::AAPCS_VFP && !isVariadic) {
4240     if (const VectorType *VT = Ty->getAs<VectorType>()) {
4241       uint64_t Size = getContext().getTypeSize(VT);
4242       // Size of a legal vector should be power of 2 and above 64.
4243       markAllocatedVFPs(Size >= 128 ? 4 : 2, Size / 32);
4244       IsCPRC = true;
4245     }
4246   }
4247   // Update VFPRegs for floating point types.
4248   if (getABIKind() == ARMABIInfo::AAPCS_VFP && !isVariadic) {
4249     if (const BuiltinType *BT = Ty->getAs<BuiltinType>()) {
4250       if (BT->getKind() == BuiltinType::Half ||
4251           BT->getKind() == BuiltinType::Float) {
4252         markAllocatedVFPs(1, 1);
4253         IsCPRC = true;
4254       }
4255       if (BT->getKind() == BuiltinType::Double ||
4256           BT->getKind() == BuiltinType::LongDouble) {
4257         markAllocatedVFPs(2, 2);
4258         IsCPRC = true;
4259       }
4260     }
4261   }
4262 
4263   if (!isAggregateTypeForABI(Ty)) {
4264     // Treat an enum type as its underlying type.
4265     if (const EnumType *EnumTy = Ty->getAs<EnumType>()) {
4266       Ty = EnumTy->getDecl()->getIntegerType();
4267     }
4268 
4269     unsigned Size = getContext().getTypeSize(Ty);
4270     if (!IsCPRC)
4271       markAllocatedGPRs(Size > 32 ? 2 : 1, (Size + 31) / 32);
4272     return (Ty->isPromotableIntegerType() ?
4273             ABIArgInfo::getExtend() : ABIArgInfo::getDirect());
4274   }
4275 
4276   if (CGCXXABI::RecordArgABI RAA = getRecordArgABI(Ty, getCXXABI())) {
4277     markAllocatedGPRs(1, 1);
4278     return ABIArgInfo::getIndirect(0, RAA == CGCXXABI::RAA_DirectInMemory);
4279   }
4280 
4281   // Ignore empty records.
4282   if (isEmptyRecord(getContext(), Ty, true))
4283     return ABIArgInfo::getIgnore();
4284 
4285   if (getABIKind() == ARMABIInfo::AAPCS_VFP && !isVariadic) {
4286     // Homogeneous Aggregates need to be expanded when we can fit the aggregate
4287     // into VFP registers.
4288     const Type *Base = nullptr;
4289     uint64_t Members = 0;
4290     if (isHomogeneousAggregate(Ty, Base, getContext(), &Members)) {
4291       assert(Base && "Base class should be set for homogeneous aggregate");
4292       // Base can be a floating-point or a vector.
4293       if (Base->isVectorType()) {
4294         // ElementSize is in number of floats.
4295         unsigned ElementSize = getContext().getTypeSize(Base) == 64 ? 2 : 4;
4296         markAllocatedVFPs(ElementSize,
4297                           Members * ElementSize);
4298       } else if (Base->isSpecificBuiltinType(BuiltinType::Float))
4299         markAllocatedVFPs(1, Members);
4300       else {
4301         assert(Base->isSpecificBuiltinType(BuiltinType::Double) ||
4302                Base->isSpecificBuiltinType(BuiltinType::LongDouble));
4303         markAllocatedVFPs(2, Members * 2);
4304       }
4305       IsCPRC = true;
4306       return ABIArgInfo::getDirect();
4307     }
4308   }
4309 
4310   // Support byval for ARM.
4311   // The ABI alignment for APCS is 4-byte and for AAPCS at least 4-byte and at
4312   // most 8-byte. We realign the indirect argument if type alignment is bigger
4313   // than ABI alignment.
4314   uint64_t ABIAlign = 4;
4315   uint64_t TyAlign = getContext().getTypeAlign(Ty) / 8;
4316   if (getABIKind() == ARMABIInfo::AAPCS_VFP ||
4317       getABIKind() == ARMABIInfo::AAPCS)
4318     ABIAlign = std::min(std::max(TyAlign, (uint64_t)4), (uint64_t)8);
4319   if (getContext().getTypeSizeInChars(Ty) > CharUnits::fromQuantity(64)) {
4320     // Update Allocated GPRs. Since this is only used when the size of the
4321     // argument is greater than 64 bytes, this will always use up any available
4322     // registers (of which there are 4). We also don't care about getting the
4323     // alignment right, because general-purpose registers cannot be back-filled.
4324     markAllocatedGPRs(1, 4);
4325     return ABIArgInfo::getIndirect(TyAlign, /*ByVal=*/true,
4326            /*Realign=*/TyAlign > ABIAlign);
4327   }
4328 
4329   // Otherwise, pass by coercing to a structure of the appropriate size.
4330   llvm::Type* ElemTy;
4331   unsigned SizeRegs;
4332   // FIXME: Try to match the types of the arguments more accurately where
4333   // we can.
4334   if (getContext().getTypeAlign(Ty) <= 32) {
4335     ElemTy = llvm::Type::getInt32Ty(getVMContext());
4336     SizeRegs = (getContext().getTypeSize(Ty) + 31) / 32;
4337     markAllocatedGPRs(1, SizeRegs);
4338   } else {
4339     ElemTy = llvm::Type::getInt64Ty(getVMContext());
4340     SizeRegs = (getContext().getTypeSize(Ty) + 63) / 64;
4341     markAllocatedGPRs(2, SizeRegs * 2);
4342   }
4343 
4344   llvm::Type *STy =
4345     llvm::StructType::get(llvm::ArrayType::get(ElemTy, SizeRegs), NULL);
4346   return ABIArgInfo::getDirect(STy);
4347 }
4348 
4349 static bool isIntegerLikeType(QualType Ty, ASTContext &Context,
4350                               llvm::LLVMContext &VMContext) {
4351   // APCS, C Language Calling Conventions, Non-Simple Return Values: A structure
4352   // is called integer-like if its size is less than or equal to one word, and
4353   // the offset of each of its addressable sub-fields is zero.
4354 
4355   uint64_t Size = Context.getTypeSize(Ty);
4356 
4357   // Check that the type fits in a word.
4358   if (Size > 32)
4359     return false;
4360 
4361   // FIXME: Handle vector types!
4362   if (Ty->isVectorType())
4363     return false;
4364 
4365   // Float types are never treated as "integer like".
4366   if (Ty->isRealFloatingType())
4367     return false;
4368 
4369   // If this is a builtin or pointer type then it is ok.
4370   if (Ty->getAs<BuiltinType>() || Ty->isPointerType())
4371     return true;
4372 
4373   // Small complex integer types are "integer like".
4374   if (const ComplexType *CT = Ty->getAs<ComplexType>())
4375     return isIntegerLikeType(CT->getElementType(), Context, VMContext);
4376 
4377   // Single element and zero sized arrays should be allowed, by the definition
4378   // above, but they are not.
4379 
4380   // Otherwise, it must be a record type.
4381   const RecordType *RT = Ty->getAs<RecordType>();
4382   if (!RT) return false;
4383 
4384   // Ignore records with flexible arrays.
4385   const RecordDecl *RD = RT->getDecl();
4386   if (RD->hasFlexibleArrayMember())
4387     return false;
4388 
4389   // Check that all sub-fields are at offset 0, and are themselves "integer
4390   // like".
4391   const ASTRecordLayout &Layout = Context.getASTRecordLayout(RD);
4392 
4393   bool HadField = false;
4394   unsigned idx = 0;
4395   for (RecordDecl::field_iterator i = RD->field_begin(), e = RD->field_end();
4396        i != e; ++i, ++idx) {
4397     const FieldDecl *FD = *i;
4398 
4399     // Bit-fields are not addressable, we only need to verify they are "integer
4400     // like". We still have to disallow a subsequent non-bitfield, for example:
4401     //   struct { int : 0; int x }
4402     // is non-integer like according to gcc.
4403     if (FD->isBitField()) {
4404       if (!RD->isUnion())
4405         HadField = true;
4406 
4407       if (!isIntegerLikeType(FD->getType(), Context, VMContext))
4408         return false;
4409 
4410       continue;
4411     }
4412 
4413     // Check if this field is at offset 0.
4414     if (Layout.getFieldOffset(idx) != 0)
4415       return false;
4416 
4417     if (!isIntegerLikeType(FD->getType(), Context, VMContext))
4418       return false;
4419 
4420     // Only allow at most one field in a structure. This doesn't match the
4421     // wording above, but follows gcc in situations with a field following an
4422     // empty structure.
4423     if (!RD->isUnion()) {
4424       if (HadField)
4425         return false;
4426 
4427       HadField = true;
4428     }
4429   }
4430 
4431   return true;
4432 }
4433 
4434 ABIArgInfo ARMABIInfo::classifyReturnType(QualType RetTy,
4435                                           bool isVariadic) const {
4436   if (RetTy->isVoidType())
4437     return ABIArgInfo::getIgnore();
4438 
4439   // Large vector types should be returned via memory.
4440   if (RetTy->isVectorType() && getContext().getTypeSize(RetTy) > 128) {
4441     markAllocatedGPRs(1, 1);
4442     return ABIArgInfo::getIndirect(0);
4443   }
4444 
4445   if (!isAggregateTypeForABI(RetTy)) {
4446     // Treat an enum type as its underlying type.
4447     if (const EnumType *EnumTy = RetTy->getAs<EnumType>())
4448       RetTy = EnumTy->getDecl()->getIntegerType();
4449 
4450     return (RetTy->isPromotableIntegerType() ?
4451             ABIArgInfo::getExtend() : ABIArgInfo::getDirect());
4452   }
4453 
4454   // Are we following APCS?
4455   if (getABIKind() == APCS) {
4456     if (isEmptyRecord(getContext(), RetTy, false))
4457       return ABIArgInfo::getIgnore();
4458 
4459     // Complex types are all returned as packed integers.
4460     //
4461     // FIXME: Consider using 2 x vector types if the back end handles them
4462     // correctly.
4463     if (RetTy->isAnyComplexType())
4464       return ABIArgInfo::getDirect(llvm::IntegerType::get(getVMContext(),
4465                                               getContext().getTypeSize(RetTy)));
4466 
4467     // Integer like structures are returned in r0.
4468     if (isIntegerLikeType(RetTy, getContext(), getVMContext())) {
4469       // Return in the smallest viable integer type.
4470       uint64_t Size = getContext().getTypeSize(RetTy);
4471       if (Size <= 8)
4472         return ABIArgInfo::getDirect(llvm::Type::getInt8Ty(getVMContext()));
4473       if (Size <= 16)
4474         return ABIArgInfo::getDirect(llvm::Type::getInt16Ty(getVMContext()));
4475       return ABIArgInfo::getDirect(llvm::Type::getInt32Ty(getVMContext()));
4476     }
4477 
4478     // Otherwise return in memory.
4479     markAllocatedGPRs(1, 1);
4480     return ABIArgInfo::getIndirect(0);
4481   }
4482 
4483   // Otherwise this is an AAPCS variant.
4484 
4485   if (isEmptyRecord(getContext(), RetTy, true))
4486     return ABIArgInfo::getIgnore();
4487 
4488   // Check for homogeneous aggregates with AAPCS-VFP.
4489   if (getABIKind() == AAPCS_VFP && !isVariadic) {
4490     const Type *Base = nullptr;
4491     if (isHomogeneousAggregate(RetTy, Base, getContext())) {
4492       assert(Base && "Base class should be set for homogeneous aggregate");
4493       // Homogeneous Aggregates are returned directly.
4494       return ABIArgInfo::getDirect();
4495     }
4496   }
4497 
4498   // Aggregates <= 4 bytes are returned in r0; other aggregates
4499   // are returned indirectly.
4500   uint64_t Size = getContext().getTypeSize(RetTy);
4501   if (Size <= 32) {
4502     if (getDataLayout().isBigEndian())
4503       // Return in 32 bit integer integer type (as if loaded by LDR, AAPCS 5.4)
4504       return ABIArgInfo::getDirect(llvm::Type::getInt32Ty(getVMContext()));
4505 
4506     // Return in the smallest viable integer type.
4507     if (Size <= 8)
4508       return ABIArgInfo::getDirect(llvm::Type::getInt8Ty(getVMContext()));
4509     if (Size <= 16)
4510       return ABIArgInfo::getDirect(llvm::Type::getInt16Ty(getVMContext()));
4511     return ABIArgInfo::getDirect(llvm::Type::getInt32Ty(getVMContext()));
4512   }
4513 
4514   markAllocatedGPRs(1, 1);
4515   return ABIArgInfo::getIndirect(0);
4516 }
4517 
4518 /// isIllegalVector - check whether Ty is an illegal vector type.
4519 bool ARMABIInfo::isIllegalVectorType(QualType Ty) const {
4520   if (const VectorType *VT = Ty->getAs<VectorType>()) {
4521     // Check whether VT is legal.
4522     unsigned NumElements = VT->getNumElements();
4523     uint64_t Size = getContext().getTypeSize(VT);
4524     // NumElements should be power of 2.
4525     if ((NumElements & (NumElements - 1)) != 0)
4526       return true;
4527     // Size should be greater than 32 bits.
4528     return Size <= 32;
4529   }
4530   return false;
4531 }
4532 
4533 llvm::Value *ARMABIInfo::EmitVAArg(llvm::Value *VAListAddr, QualType Ty,
4534                                    CodeGenFunction &CGF) const {
4535   llvm::Type *BP = CGF.Int8PtrTy;
4536   llvm::Type *BPP = CGF.Int8PtrPtrTy;
4537 
4538   CGBuilderTy &Builder = CGF.Builder;
4539   llvm::Value *VAListAddrAsBPP = Builder.CreateBitCast(VAListAddr, BPP, "ap");
4540   llvm::Value *Addr = Builder.CreateLoad(VAListAddrAsBPP, "ap.cur");
4541 
4542   if (isEmptyRecord(getContext(), Ty, true)) {
4543     // These are ignored for parameter passing purposes.
4544     llvm::Type *PTy = llvm::PointerType::getUnqual(CGF.ConvertType(Ty));
4545     return Builder.CreateBitCast(Addr, PTy);
4546   }
4547 
4548   uint64_t Size = CGF.getContext().getTypeSize(Ty) / 8;
4549   uint64_t TyAlign = CGF.getContext().getTypeAlign(Ty) / 8;
4550   bool IsIndirect = false;
4551 
4552   // The ABI alignment for 64-bit or 128-bit vectors is 8 for AAPCS and 4 for
4553   // APCS. For AAPCS, the ABI alignment is at least 4-byte and at most 8-byte.
4554   if (getABIKind() == ARMABIInfo::AAPCS_VFP ||
4555       getABIKind() == ARMABIInfo::AAPCS)
4556     TyAlign = std::min(std::max(TyAlign, (uint64_t)4), (uint64_t)8);
4557   else
4558     TyAlign = 4;
4559   // Use indirect if size of the illegal vector is bigger than 16 bytes.
4560   if (isIllegalVectorType(Ty) && Size > 16) {
4561     IsIndirect = true;
4562     Size = 4;
4563     TyAlign = 4;
4564   }
4565 
4566   // Handle address alignment for ABI alignment > 4 bytes.
4567   if (TyAlign > 4) {
4568     assert((TyAlign & (TyAlign - 1)) == 0 &&
4569            "Alignment is not power of 2!");
4570     llvm::Value *AddrAsInt = Builder.CreatePtrToInt(Addr, CGF.Int32Ty);
4571     AddrAsInt = Builder.CreateAdd(AddrAsInt, Builder.getInt32(TyAlign - 1));
4572     AddrAsInt = Builder.CreateAnd(AddrAsInt, Builder.getInt32(~(TyAlign - 1)));
4573     Addr = Builder.CreateIntToPtr(AddrAsInt, BP, "ap.align");
4574   }
4575 
4576   uint64_t Offset =
4577     llvm::RoundUpToAlignment(Size, 4);
4578   llvm::Value *NextAddr =
4579     Builder.CreateGEP(Addr, llvm::ConstantInt::get(CGF.Int32Ty, Offset),
4580                       "ap.next");
4581   Builder.CreateStore(NextAddr, VAListAddrAsBPP);
4582 
4583   if (IsIndirect)
4584     Addr = Builder.CreateLoad(Builder.CreateBitCast(Addr, BPP));
4585   else if (TyAlign < CGF.getContext().getTypeAlign(Ty) / 8) {
4586     // We can't directly cast ap.cur to pointer to a vector type, since ap.cur
4587     // may not be correctly aligned for the vector type. We create an aligned
4588     // temporary space and copy the content over from ap.cur to the temporary
4589     // space. This is necessary if the natural alignment of the type is greater
4590     // than the ABI alignment.
4591     llvm::Type *I8PtrTy = Builder.getInt8PtrTy();
4592     CharUnits CharSize = getContext().getTypeSizeInChars(Ty);
4593     llvm::Value *AlignedTemp = CGF.CreateTempAlloca(CGF.ConvertType(Ty),
4594                                                     "var.align");
4595     llvm::Value *Dst = Builder.CreateBitCast(AlignedTemp, I8PtrTy);
4596     llvm::Value *Src = Builder.CreateBitCast(Addr, I8PtrTy);
4597     Builder.CreateMemCpy(Dst, Src,
4598         llvm::ConstantInt::get(CGF.IntPtrTy, CharSize.getQuantity()),
4599         TyAlign, false);
4600     Addr = AlignedTemp; //The content is in aligned location.
4601   }
4602   llvm::Type *PTy =
4603     llvm::PointerType::getUnqual(CGF.ConvertType(Ty));
4604   llvm::Value *AddrTyped = Builder.CreateBitCast(Addr, PTy);
4605 
4606   return AddrTyped;
4607 }
4608 
4609 namespace {
4610 
4611 class NaClARMABIInfo : public ABIInfo {
4612  public:
4613   NaClARMABIInfo(CodeGen::CodeGenTypes &CGT, ARMABIInfo::ABIKind Kind)
4614       : ABIInfo(CGT), PInfo(CGT), NInfo(CGT, Kind) {}
4615   void computeInfo(CGFunctionInfo &FI) const override;
4616   llvm::Value *EmitVAArg(llvm::Value *VAListAddr, QualType Ty,
4617                          CodeGenFunction &CGF) const override;
4618  private:
4619   PNaClABIInfo PInfo; // Used for generating calls with pnaclcall callingconv.
4620   ARMABIInfo NInfo; // Used for everything else.
4621 };
4622 
4623 class NaClARMTargetCodeGenInfo : public TargetCodeGenInfo  {
4624  public:
4625   NaClARMTargetCodeGenInfo(CodeGen::CodeGenTypes &CGT, ARMABIInfo::ABIKind Kind)
4626       : TargetCodeGenInfo(new NaClARMABIInfo(CGT, Kind)) {}
4627 };
4628 
4629 }
4630 
4631 void NaClARMABIInfo::computeInfo(CGFunctionInfo &FI) const {
4632   if (FI.getASTCallingConvention() == CC_PnaclCall)
4633     PInfo.computeInfo(FI);
4634   else
4635     static_cast<const ABIInfo&>(NInfo).computeInfo(FI);
4636 }
4637 
4638 llvm::Value *NaClARMABIInfo::EmitVAArg(llvm::Value *VAListAddr, QualType Ty,
4639                                        CodeGenFunction &CGF) const {
4640   // Always use the native convention; calling pnacl-style varargs functions
4641   // is unsupported.
4642   return static_cast<const ABIInfo&>(NInfo).EmitVAArg(VAListAddr, Ty, CGF);
4643 }
4644 
4645 //===----------------------------------------------------------------------===//
4646 // NVPTX ABI Implementation
4647 //===----------------------------------------------------------------------===//
4648 
4649 namespace {
4650 
4651 class NVPTXABIInfo : public ABIInfo {
4652 public:
4653   NVPTXABIInfo(CodeGenTypes &CGT) : ABIInfo(CGT) {}
4654 
4655   ABIArgInfo classifyReturnType(QualType RetTy) const;
4656   ABIArgInfo classifyArgumentType(QualType Ty) const;
4657 
4658   void computeInfo(CGFunctionInfo &FI) const override;
4659   llvm::Value *EmitVAArg(llvm::Value *VAListAddr, QualType Ty,
4660                          CodeGenFunction &CFG) const override;
4661 };
4662 
4663 class NVPTXTargetCodeGenInfo : public TargetCodeGenInfo {
4664 public:
4665   NVPTXTargetCodeGenInfo(CodeGenTypes &CGT)
4666     : TargetCodeGenInfo(new NVPTXABIInfo(CGT)) {}
4667 
4668   void SetTargetAttributes(const Decl *D, llvm::GlobalValue *GV,
4669                            CodeGen::CodeGenModule &M) const override;
4670 private:
4671   // Adds a NamedMDNode with F, Name, and Operand as operands, and adds the
4672   // resulting MDNode to the nvvm.annotations MDNode.
4673   static void addNVVMMetadata(llvm::Function *F, StringRef Name, int Operand);
4674 };
4675 
4676 ABIArgInfo NVPTXABIInfo::classifyReturnType(QualType RetTy) const {
4677   if (RetTy->isVoidType())
4678     return ABIArgInfo::getIgnore();
4679 
4680   // note: this is different from default ABI
4681   if (!RetTy->isScalarType())
4682     return ABIArgInfo::getDirect();
4683 
4684   // Treat an enum type as its underlying type.
4685   if (const EnumType *EnumTy = RetTy->getAs<EnumType>())
4686     RetTy = EnumTy->getDecl()->getIntegerType();
4687 
4688   return (RetTy->isPromotableIntegerType() ?
4689           ABIArgInfo::getExtend() : ABIArgInfo::getDirect());
4690 }
4691 
4692 ABIArgInfo NVPTXABIInfo::classifyArgumentType(QualType Ty) const {
4693   // Treat an enum type as its underlying type.
4694   if (const EnumType *EnumTy = Ty->getAs<EnumType>())
4695     Ty = EnumTy->getDecl()->getIntegerType();
4696 
4697   return (Ty->isPromotableIntegerType() ?
4698           ABIArgInfo::getExtend() : ABIArgInfo::getDirect());
4699 }
4700 
4701 void NVPTXABIInfo::computeInfo(CGFunctionInfo &FI) const {
4702   if (!getCXXABI().classifyReturnType(FI))
4703     FI.getReturnInfo() = classifyReturnType(FI.getReturnType());
4704   for (auto &I : FI.arguments())
4705     I.info = classifyArgumentType(I.type);
4706 
4707   // Always honor user-specified calling convention.
4708   if (FI.getCallingConvention() != llvm::CallingConv::C)
4709     return;
4710 
4711   FI.setEffectiveCallingConvention(getRuntimeCC());
4712 }
4713 
4714 llvm::Value *NVPTXABIInfo::EmitVAArg(llvm::Value *VAListAddr, QualType Ty,
4715                                      CodeGenFunction &CFG) const {
4716   llvm_unreachable("NVPTX does not support varargs");
4717 }
4718 
4719 void NVPTXTargetCodeGenInfo::
4720 SetTargetAttributes(const Decl *D, llvm::GlobalValue *GV,
4721                     CodeGen::CodeGenModule &M) const{
4722   const FunctionDecl *FD = dyn_cast<FunctionDecl>(D);
4723   if (!FD) return;
4724 
4725   llvm::Function *F = cast<llvm::Function>(GV);
4726 
4727   // Perform special handling in OpenCL mode
4728   if (M.getLangOpts().OpenCL) {
4729     // Use OpenCL function attributes to check for kernel functions
4730     // By default, all functions are device functions
4731     if (FD->hasAttr<OpenCLKernelAttr>()) {
4732       // OpenCL __kernel functions get kernel metadata
4733       // Create !{<func-ref>, metadata !"kernel", i32 1} node
4734       addNVVMMetadata(F, "kernel", 1);
4735       // And kernel functions are not subject to inlining
4736       F->addFnAttr(llvm::Attribute::NoInline);
4737     }
4738   }
4739 
4740   // Perform special handling in CUDA mode.
4741   if (M.getLangOpts().CUDA) {
4742     // CUDA __global__ functions get a kernel metadata entry.  Since
4743     // __global__ functions cannot be called from the device, we do not
4744     // need to set the noinline attribute.
4745     if (FD->hasAttr<CUDAGlobalAttr>()) {
4746       // Create !{<func-ref>, metadata !"kernel", i32 1} node
4747       addNVVMMetadata(F, "kernel", 1);
4748     }
4749     if (FD->hasAttr<CUDALaunchBoundsAttr>()) {
4750       // Create !{<func-ref>, metadata !"maxntidx", i32 <val>} node
4751       addNVVMMetadata(F, "maxntidx",
4752                       FD->getAttr<CUDALaunchBoundsAttr>()->getMaxThreads());
4753       // min blocks is a default argument for CUDALaunchBoundsAttr, so getting a
4754       // zero value from getMinBlocks either means it was not specified in
4755       // __launch_bounds__ or the user specified a 0 value. In both cases, we
4756       // don't have to add a PTX directive.
4757       int MinCTASM = FD->getAttr<CUDALaunchBoundsAttr>()->getMinBlocks();
4758       if (MinCTASM > 0) {
4759         // Create !{<func-ref>, metadata !"minctasm", i32 <val>} node
4760         addNVVMMetadata(F, "minctasm", MinCTASM);
4761       }
4762     }
4763   }
4764 }
4765 
4766 void NVPTXTargetCodeGenInfo::addNVVMMetadata(llvm::Function *F, StringRef Name,
4767                                              int Operand) {
4768   llvm::Module *M = F->getParent();
4769   llvm::LLVMContext &Ctx = M->getContext();
4770 
4771   // Get "nvvm.annotations" metadata node
4772   llvm::NamedMDNode *MD = M->getOrInsertNamedMetadata("nvvm.annotations");
4773 
4774   llvm::Value *MDVals[] = {
4775       F, llvm::MDString::get(Ctx, Name),
4776       llvm::ConstantInt::get(llvm::Type::getInt32Ty(Ctx), Operand)};
4777   // Append metadata to nvvm.annotations
4778   MD->addOperand(llvm::MDNode::get(Ctx, MDVals));
4779 }
4780 }
4781 
4782 //===----------------------------------------------------------------------===//
4783 // SystemZ ABI Implementation
4784 //===----------------------------------------------------------------------===//
4785 
4786 namespace {
4787 
4788 class SystemZABIInfo : public ABIInfo {
4789 public:
4790   SystemZABIInfo(CodeGenTypes &CGT) : ABIInfo(CGT) {}
4791 
4792   bool isPromotableIntegerType(QualType Ty) const;
4793   bool isCompoundType(QualType Ty) const;
4794   bool isFPArgumentType(QualType Ty) const;
4795 
4796   ABIArgInfo classifyReturnType(QualType RetTy) const;
4797   ABIArgInfo classifyArgumentType(QualType ArgTy) const;
4798 
4799   void computeInfo(CGFunctionInfo &FI) const override {
4800     if (!getCXXABI().classifyReturnType(FI))
4801       FI.getReturnInfo() = classifyReturnType(FI.getReturnType());
4802     for (auto &I : FI.arguments())
4803       I.info = classifyArgumentType(I.type);
4804   }
4805 
4806   llvm::Value *EmitVAArg(llvm::Value *VAListAddr, QualType Ty,
4807                          CodeGenFunction &CGF) const override;
4808 };
4809 
4810 class SystemZTargetCodeGenInfo : public TargetCodeGenInfo {
4811 public:
4812   SystemZTargetCodeGenInfo(CodeGenTypes &CGT)
4813     : TargetCodeGenInfo(new SystemZABIInfo(CGT)) {}
4814 };
4815 
4816 }
4817 
4818 bool SystemZABIInfo::isPromotableIntegerType(QualType Ty) const {
4819   // Treat an enum type as its underlying type.
4820   if (const EnumType *EnumTy = Ty->getAs<EnumType>())
4821     Ty = EnumTy->getDecl()->getIntegerType();
4822 
4823   // Promotable integer types are required to be promoted by the ABI.
4824   if (Ty->isPromotableIntegerType())
4825     return true;
4826 
4827   // 32-bit values must also be promoted.
4828   if (const BuiltinType *BT = Ty->getAs<BuiltinType>())
4829     switch (BT->getKind()) {
4830     case BuiltinType::Int:
4831     case BuiltinType::UInt:
4832       return true;
4833     default:
4834       return false;
4835     }
4836   return false;
4837 }
4838 
4839 bool SystemZABIInfo::isCompoundType(QualType Ty) const {
4840   return Ty->isAnyComplexType() || isAggregateTypeForABI(Ty);
4841 }
4842 
4843 bool SystemZABIInfo::isFPArgumentType(QualType Ty) const {
4844   if (const BuiltinType *BT = Ty->getAs<BuiltinType>())
4845     switch (BT->getKind()) {
4846     case BuiltinType::Float:
4847     case BuiltinType::Double:
4848       return true;
4849     default:
4850       return false;
4851     }
4852 
4853   if (const RecordType *RT = Ty->getAsStructureType()) {
4854     const RecordDecl *RD = RT->getDecl();
4855     bool Found = false;
4856 
4857     // If this is a C++ record, check the bases first.
4858     if (const CXXRecordDecl *CXXRD = dyn_cast<CXXRecordDecl>(RD))
4859       for (const auto &I : CXXRD->bases()) {
4860         QualType Base = I.getType();
4861 
4862         // Empty bases don't affect things either way.
4863         if (isEmptyRecord(getContext(), Base, true))
4864           continue;
4865 
4866         if (Found)
4867           return false;
4868         Found = isFPArgumentType(Base);
4869         if (!Found)
4870           return false;
4871       }
4872 
4873     // Check the fields.
4874     for (const auto *FD : RD->fields()) {
4875       // Empty bitfields don't affect things either way.
4876       // Unlike isSingleElementStruct(), empty structure and array fields
4877       // do count.  So do anonymous bitfields that aren't zero-sized.
4878       if (FD->isBitField() && FD->getBitWidthValue(getContext()) == 0)
4879         return true;
4880 
4881       // Unlike isSingleElementStruct(), arrays do not count.
4882       // Nested isFPArgumentType structures still do though.
4883       if (Found)
4884         return false;
4885       Found = isFPArgumentType(FD->getType());
4886       if (!Found)
4887         return false;
4888     }
4889 
4890     // Unlike isSingleElementStruct(), trailing padding is allowed.
4891     // An 8-byte aligned struct s { float f; } is passed as a double.
4892     return Found;
4893   }
4894 
4895   return false;
4896 }
4897 
4898 llvm::Value *SystemZABIInfo::EmitVAArg(llvm::Value *VAListAddr, QualType Ty,
4899                                        CodeGenFunction &CGF) const {
4900   // Assume that va_list type is correct; should be pointer to LLVM type:
4901   // struct {
4902   //   i64 __gpr;
4903   //   i64 __fpr;
4904   //   i8 *__overflow_arg_area;
4905   //   i8 *__reg_save_area;
4906   // };
4907 
4908   // Every argument occupies 8 bytes and is passed by preference in either
4909   // GPRs or FPRs.
4910   Ty = CGF.getContext().getCanonicalType(Ty);
4911   ABIArgInfo AI = classifyArgumentType(Ty);
4912   bool InFPRs = isFPArgumentType(Ty);
4913 
4914   llvm::Type *APTy = llvm::PointerType::getUnqual(CGF.ConvertTypeForMem(Ty));
4915   bool IsIndirect = AI.isIndirect();
4916   unsigned UnpaddedBitSize;
4917   if (IsIndirect) {
4918     APTy = llvm::PointerType::getUnqual(APTy);
4919     UnpaddedBitSize = 64;
4920   } else
4921     UnpaddedBitSize = getContext().getTypeSize(Ty);
4922   unsigned PaddedBitSize = 64;
4923   assert((UnpaddedBitSize <= PaddedBitSize) && "Invalid argument size.");
4924 
4925   unsigned PaddedSize = PaddedBitSize / 8;
4926   unsigned Padding = (PaddedBitSize - UnpaddedBitSize) / 8;
4927 
4928   unsigned MaxRegs, RegCountField, RegSaveIndex, RegPadding;
4929   if (InFPRs) {
4930     MaxRegs = 4; // Maximum of 4 FPR arguments
4931     RegCountField = 1; // __fpr
4932     RegSaveIndex = 16; // save offset for f0
4933     RegPadding = 0; // floats are passed in the high bits of an FPR
4934   } else {
4935     MaxRegs = 5; // Maximum of 5 GPR arguments
4936     RegCountField = 0; // __gpr
4937     RegSaveIndex = 2; // save offset for r2
4938     RegPadding = Padding; // values are passed in the low bits of a GPR
4939   }
4940 
4941   llvm::Value *RegCountPtr =
4942     CGF.Builder.CreateStructGEP(VAListAddr, RegCountField, "reg_count_ptr");
4943   llvm::Value *RegCount = CGF.Builder.CreateLoad(RegCountPtr, "reg_count");
4944   llvm::Type *IndexTy = RegCount->getType();
4945   llvm::Value *MaxRegsV = llvm::ConstantInt::get(IndexTy, MaxRegs);
4946   llvm::Value *InRegs = CGF.Builder.CreateICmpULT(RegCount, MaxRegsV,
4947                                                  "fits_in_regs");
4948 
4949   llvm::BasicBlock *InRegBlock = CGF.createBasicBlock("vaarg.in_reg");
4950   llvm::BasicBlock *InMemBlock = CGF.createBasicBlock("vaarg.in_mem");
4951   llvm::BasicBlock *ContBlock = CGF.createBasicBlock("vaarg.end");
4952   CGF.Builder.CreateCondBr(InRegs, InRegBlock, InMemBlock);
4953 
4954   // Emit code to load the value if it was passed in registers.
4955   CGF.EmitBlock(InRegBlock);
4956 
4957   // Work out the address of an argument register.
4958   llvm::Value *PaddedSizeV = llvm::ConstantInt::get(IndexTy, PaddedSize);
4959   llvm::Value *ScaledRegCount =
4960     CGF.Builder.CreateMul(RegCount, PaddedSizeV, "scaled_reg_count");
4961   llvm::Value *RegBase =
4962     llvm::ConstantInt::get(IndexTy, RegSaveIndex * PaddedSize + RegPadding);
4963   llvm::Value *RegOffset =
4964     CGF.Builder.CreateAdd(ScaledRegCount, RegBase, "reg_offset");
4965   llvm::Value *RegSaveAreaPtr =
4966     CGF.Builder.CreateStructGEP(VAListAddr, 3, "reg_save_area_ptr");
4967   llvm::Value *RegSaveArea =
4968     CGF.Builder.CreateLoad(RegSaveAreaPtr, "reg_save_area");
4969   llvm::Value *RawRegAddr =
4970     CGF.Builder.CreateGEP(RegSaveArea, RegOffset, "raw_reg_addr");
4971   llvm::Value *RegAddr =
4972     CGF.Builder.CreateBitCast(RawRegAddr, APTy, "reg_addr");
4973 
4974   // Update the register count
4975   llvm::Value *One = llvm::ConstantInt::get(IndexTy, 1);
4976   llvm::Value *NewRegCount =
4977     CGF.Builder.CreateAdd(RegCount, One, "reg_count");
4978   CGF.Builder.CreateStore(NewRegCount, RegCountPtr);
4979   CGF.EmitBranch(ContBlock);
4980 
4981   // Emit code to load the value if it was passed in memory.
4982   CGF.EmitBlock(InMemBlock);
4983 
4984   // Work out the address of a stack argument.
4985   llvm::Value *OverflowArgAreaPtr =
4986     CGF.Builder.CreateStructGEP(VAListAddr, 2, "overflow_arg_area_ptr");
4987   llvm::Value *OverflowArgArea =
4988     CGF.Builder.CreateLoad(OverflowArgAreaPtr, "overflow_arg_area");
4989   llvm::Value *PaddingV = llvm::ConstantInt::get(IndexTy, Padding);
4990   llvm::Value *RawMemAddr =
4991     CGF.Builder.CreateGEP(OverflowArgArea, PaddingV, "raw_mem_addr");
4992   llvm::Value *MemAddr =
4993     CGF.Builder.CreateBitCast(RawMemAddr, APTy, "mem_addr");
4994 
4995   // Update overflow_arg_area_ptr pointer
4996   llvm::Value *NewOverflowArgArea =
4997     CGF.Builder.CreateGEP(OverflowArgArea, PaddedSizeV, "overflow_arg_area");
4998   CGF.Builder.CreateStore(NewOverflowArgArea, OverflowArgAreaPtr);
4999   CGF.EmitBranch(ContBlock);
5000 
5001   // Return the appropriate result.
5002   CGF.EmitBlock(ContBlock);
5003   llvm::PHINode *ResAddr = CGF.Builder.CreatePHI(APTy, 2, "va_arg.addr");
5004   ResAddr->addIncoming(RegAddr, InRegBlock);
5005   ResAddr->addIncoming(MemAddr, InMemBlock);
5006 
5007   if (IsIndirect)
5008     return CGF.Builder.CreateLoad(ResAddr, "indirect_arg");
5009 
5010   return ResAddr;
5011 }
5012 
5013 ABIArgInfo SystemZABIInfo::classifyReturnType(QualType RetTy) const {
5014   if (RetTy->isVoidType())
5015     return ABIArgInfo::getIgnore();
5016   if (isCompoundType(RetTy) || getContext().getTypeSize(RetTy) > 64)
5017     return ABIArgInfo::getIndirect(0);
5018   return (isPromotableIntegerType(RetTy) ?
5019           ABIArgInfo::getExtend() : ABIArgInfo::getDirect());
5020 }
5021 
5022 ABIArgInfo SystemZABIInfo::classifyArgumentType(QualType Ty) const {
5023   // Handle the generic C++ ABI.
5024   if (CGCXXABI::RecordArgABI RAA = getRecordArgABI(Ty, getCXXABI()))
5025     return ABIArgInfo::getIndirect(0, RAA == CGCXXABI::RAA_DirectInMemory);
5026 
5027   // Integers and enums are extended to full register width.
5028   if (isPromotableIntegerType(Ty))
5029     return ABIArgInfo::getExtend();
5030 
5031   // Values that are not 1, 2, 4 or 8 bytes in size are passed indirectly.
5032   uint64_t Size = getContext().getTypeSize(Ty);
5033   if (Size != 8 && Size != 16 && Size != 32 && Size != 64)
5034     return ABIArgInfo::getIndirect(0, /*ByVal=*/false);
5035 
5036   // Handle small structures.
5037   if (const RecordType *RT = Ty->getAs<RecordType>()) {
5038     // Structures with flexible arrays have variable length, so really
5039     // fail the size test above.
5040     const RecordDecl *RD = RT->getDecl();
5041     if (RD->hasFlexibleArrayMember())
5042       return ABIArgInfo::getIndirect(0, /*ByVal=*/false);
5043 
5044     // The structure is passed as an unextended integer, a float, or a double.
5045     llvm::Type *PassTy;
5046     if (isFPArgumentType(Ty)) {
5047       assert(Size == 32 || Size == 64);
5048       if (Size == 32)
5049         PassTy = llvm::Type::getFloatTy(getVMContext());
5050       else
5051         PassTy = llvm::Type::getDoubleTy(getVMContext());
5052     } else
5053       PassTy = llvm::IntegerType::get(getVMContext(), Size);
5054     return ABIArgInfo::getDirect(PassTy);
5055   }
5056 
5057   // Non-structure compounds are passed indirectly.
5058   if (isCompoundType(Ty))
5059     return ABIArgInfo::getIndirect(0, /*ByVal=*/false);
5060 
5061   return ABIArgInfo::getDirect(nullptr);
5062 }
5063 
5064 //===----------------------------------------------------------------------===//
5065 // MSP430 ABI Implementation
5066 //===----------------------------------------------------------------------===//
5067 
5068 namespace {
5069 
5070 class MSP430TargetCodeGenInfo : public TargetCodeGenInfo {
5071 public:
5072   MSP430TargetCodeGenInfo(CodeGenTypes &CGT)
5073     : TargetCodeGenInfo(new DefaultABIInfo(CGT)) {}
5074   void SetTargetAttributes(const Decl *D, llvm::GlobalValue *GV,
5075                            CodeGen::CodeGenModule &M) const override;
5076 };
5077 
5078 }
5079 
5080 void MSP430TargetCodeGenInfo::SetTargetAttributes(const Decl *D,
5081                                                   llvm::GlobalValue *GV,
5082                                              CodeGen::CodeGenModule &M) const {
5083   if (const FunctionDecl *FD = dyn_cast<FunctionDecl>(D)) {
5084     if (const MSP430InterruptAttr *attr = FD->getAttr<MSP430InterruptAttr>()) {
5085       // Handle 'interrupt' attribute:
5086       llvm::Function *F = cast<llvm::Function>(GV);
5087 
5088       // Step 1: Set ISR calling convention.
5089       F->setCallingConv(llvm::CallingConv::MSP430_INTR);
5090 
5091       // Step 2: Add attributes goodness.
5092       F->addFnAttr(llvm::Attribute::NoInline);
5093 
5094       // Step 3: Emit ISR vector alias.
5095       unsigned Num = attr->getNumber() / 2;
5096       llvm::GlobalAlias::create(llvm::Function::ExternalLinkage,
5097                                 "__isr_" + Twine(Num), F);
5098     }
5099   }
5100 }
5101 
5102 //===----------------------------------------------------------------------===//
5103 // MIPS ABI Implementation.  This works for both little-endian and
5104 // big-endian variants.
5105 //===----------------------------------------------------------------------===//
5106 
5107 namespace {
5108 class MipsABIInfo : public ABIInfo {
5109   bool IsO32;
5110   unsigned MinABIStackAlignInBytes, StackAlignInBytes;
5111   void CoerceToIntArgs(uint64_t TySize,
5112                        SmallVectorImpl<llvm::Type *> &ArgList) const;
5113   llvm::Type* HandleAggregates(QualType Ty, uint64_t TySize) const;
5114   llvm::Type* returnAggregateInRegs(QualType RetTy, uint64_t Size) const;
5115   llvm::Type* getPaddingType(uint64_t Align, uint64_t Offset) const;
5116 public:
5117   MipsABIInfo(CodeGenTypes &CGT, bool _IsO32) :
5118     ABIInfo(CGT), IsO32(_IsO32), MinABIStackAlignInBytes(IsO32 ? 4 : 8),
5119     StackAlignInBytes(IsO32 ? 8 : 16) {}
5120 
5121   ABIArgInfo classifyReturnType(QualType RetTy) const;
5122   ABIArgInfo classifyArgumentType(QualType RetTy, uint64_t &Offset) const;
5123   void computeInfo(CGFunctionInfo &FI) const override;
5124   llvm::Value *EmitVAArg(llvm::Value *VAListAddr, QualType Ty,
5125                          CodeGenFunction &CGF) const override;
5126 };
5127 
5128 class MIPSTargetCodeGenInfo : public TargetCodeGenInfo {
5129   unsigned SizeOfUnwindException;
5130 public:
5131   MIPSTargetCodeGenInfo(CodeGenTypes &CGT, bool IsO32)
5132     : TargetCodeGenInfo(new MipsABIInfo(CGT, IsO32)),
5133       SizeOfUnwindException(IsO32 ? 24 : 32) {}
5134 
5135   int getDwarfEHStackPointer(CodeGen::CodeGenModule &CGM) const override {
5136     return 29;
5137   }
5138 
5139   void SetTargetAttributes(const Decl *D, llvm::GlobalValue *GV,
5140                            CodeGen::CodeGenModule &CGM) const override {
5141     const FunctionDecl *FD = dyn_cast<FunctionDecl>(D);
5142     if (!FD) return;
5143     llvm::Function *Fn = cast<llvm::Function>(GV);
5144     if (FD->hasAttr<Mips16Attr>()) {
5145       Fn->addFnAttr("mips16");
5146     }
5147     else if (FD->hasAttr<NoMips16Attr>()) {
5148       Fn->addFnAttr("nomips16");
5149     }
5150   }
5151 
5152   bool initDwarfEHRegSizeTable(CodeGen::CodeGenFunction &CGF,
5153                                llvm::Value *Address) const override;
5154 
5155   unsigned getSizeOfUnwindException() const override {
5156     return SizeOfUnwindException;
5157   }
5158 };
5159 }
5160 
5161 void MipsABIInfo::CoerceToIntArgs(uint64_t TySize,
5162                                   SmallVectorImpl<llvm::Type *> &ArgList) const {
5163   llvm::IntegerType *IntTy =
5164     llvm::IntegerType::get(getVMContext(), MinABIStackAlignInBytes * 8);
5165 
5166   // Add (TySize / MinABIStackAlignInBytes) args of IntTy.
5167   for (unsigned N = TySize / (MinABIStackAlignInBytes * 8); N; --N)
5168     ArgList.push_back(IntTy);
5169 
5170   // If necessary, add one more integer type to ArgList.
5171   unsigned R = TySize % (MinABIStackAlignInBytes * 8);
5172 
5173   if (R)
5174     ArgList.push_back(llvm::IntegerType::get(getVMContext(), R));
5175 }
5176 
5177 // In N32/64, an aligned double precision floating point field is passed in
5178 // a register.
5179 llvm::Type* MipsABIInfo::HandleAggregates(QualType Ty, uint64_t TySize) const {
5180   SmallVector<llvm::Type*, 8> ArgList, IntArgList;
5181 
5182   if (IsO32) {
5183     CoerceToIntArgs(TySize, ArgList);
5184     return llvm::StructType::get(getVMContext(), ArgList);
5185   }
5186 
5187   if (Ty->isComplexType())
5188     return CGT.ConvertType(Ty);
5189 
5190   const RecordType *RT = Ty->getAs<RecordType>();
5191 
5192   // Unions/vectors are passed in integer registers.
5193   if (!RT || !RT->isStructureOrClassType()) {
5194     CoerceToIntArgs(TySize, ArgList);
5195     return llvm::StructType::get(getVMContext(), ArgList);
5196   }
5197 
5198   const RecordDecl *RD = RT->getDecl();
5199   const ASTRecordLayout &Layout = getContext().getASTRecordLayout(RD);
5200   assert(!(TySize % 8) && "Size of structure must be multiple of 8.");
5201 
5202   uint64_t LastOffset = 0;
5203   unsigned idx = 0;
5204   llvm::IntegerType *I64 = llvm::IntegerType::get(getVMContext(), 64);
5205 
5206   // Iterate over fields in the struct/class and check if there are any aligned
5207   // double fields.
5208   for (RecordDecl::field_iterator i = RD->field_begin(), e = RD->field_end();
5209        i != e; ++i, ++idx) {
5210     const QualType Ty = i->getType();
5211     const BuiltinType *BT = Ty->getAs<BuiltinType>();
5212 
5213     if (!BT || BT->getKind() != BuiltinType::Double)
5214       continue;
5215 
5216     uint64_t Offset = Layout.getFieldOffset(idx);
5217     if (Offset % 64) // Ignore doubles that are not aligned.
5218       continue;
5219 
5220     // Add ((Offset - LastOffset) / 64) args of type i64.
5221     for (unsigned j = (Offset - LastOffset) / 64; j > 0; --j)
5222       ArgList.push_back(I64);
5223 
5224     // Add double type.
5225     ArgList.push_back(llvm::Type::getDoubleTy(getVMContext()));
5226     LastOffset = Offset + 64;
5227   }
5228 
5229   CoerceToIntArgs(TySize - LastOffset, IntArgList);
5230   ArgList.append(IntArgList.begin(), IntArgList.end());
5231 
5232   return llvm::StructType::get(getVMContext(), ArgList);
5233 }
5234 
5235 llvm::Type *MipsABIInfo::getPaddingType(uint64_t OrigOffset,
5236                                         uint64_t Offset) const {
5237   if (OrigOffset + MinABIStackAlignInBytes > Offset)
5238     return nullptr;
5239 
5240   return llvm::IntegerType::get(getVMContext(), (Offset - OrigOffset) * 8);
5241 }
5242 
5243 ABIArgInfo
5244 MipsABIInfo::classifyArgumentType(QualType Ty, uint64_t &Offset) const {
5245   uint64_t OrigOffset = Offset;
5246   uint64_t TySize = getContext().getTypeSize(Ty);
5247   uint64_t Align = getContext().getTypeAlign(Ty) / 8;
5248 
5249   Align = std::min(std::max(Align, (uint64_t)MinABIStackAlignInBytes),
5250                    (uint64_t)StackAlignInBytes);
5251   unsigned CurrOffset = llvm::RoundUpToAlignment(Offset, Align);
5252   Offset = CurrOffset + llvm::RoundUpToAlignment(TySize, Align * 8) / 8;
5253 
5254   if (isAggregateTypeForABI(Ty) || Ty->isVectorType()) {
5255     // Ignore empty aggregates.
5256     if (TySize == 0)
5257       return ABIArgInfo::getIgnore();
5258 
5259     if (CGCXXABI::RecordArgABI RAA = getRecordArgABI(Ty, getCXXABI())) {
5260       Offset = OrigOffset + MinABIStackAlignInBytes;
5261       return ABIArgInfo::getIndirect(0, RAA == CGCXXABI::RAA_DirectInMemory);
5262     }
5263 
5264     // If we have reached here, aggregates are passed directly by coercing to
5265     // another structure type. Padding is inserted if the offset of the
5266     // aggregate is unaligned.
5267     return ABIArgInfo::getDirect(HandleAggregates(Ty, TySize), 0,
5268                                  getPaddingType(OrigOffset, CurrOffset));
5269   }
5270 
5271   // Treat an enum type as its underlying type.
5272   if (const EnumType *EnumTy = Ty->getAs<EnumType>())
5273     Ty = EnumTy->getDecl()->getIntegerType();
5274 
5275   if (Ty->isPromotableIntegerType())
5276     return ABIArgInfo::getExtend();
5277 
5278   return ABIArgInfo::getDirect(
5279       nullptr, 0, IsO32 ? nullptr : getPaddingType(OrigOffset, CurrOffset));
5280 }
5281 
5282 llvm::Type*
5283 MipsABIInfo::returnAggregateInRegs(QualType RetTy, uint64_t Size) const {
5284   const RecordType *RT = RetTy->getAs<RecordType>();
5285   SmallVector<llvm::Type*, 8> RTList;
5286 
5287   if (RT && RT->isStructureOrClassType()) {
5288     const RecordDecl *RD = RT->getDecl();
5289     const ASTRecordLayout &Layout = getContext().getASTRecordLayout(RD);
5290     unsigned FieldCnt = Layout.getFieldCount();
5291 
5292     // N32/64 returns struct/classes in floating point registers if the
5293     // following conditions are met:
5294     // 1. The size of the struct/class is no larger than 128-bit.
5295     // 2. The struct/class has one or two fields all of which are floating
5296     //    point types.
5297     // 3. The offset of the first field is zero (this follows what gcc does).
5298     //
5299     // Any other composite results are returned in integer registers.
5300     //
5301     if (FieldCnt && (FieldCnt <= 2) && !Layout.getFieldOffset(0)) {
5302       RecordDecl::field_iterator b = RD->field_begin(), e = RD->field_end();
5303       for (; b != e; ++b) {
5304         const BuiltinType *BT = b->getType()->getAs<BuiltinType>();
5305 
5306         if (!BT || !BT->isFloatingPoint())
5307           break;
5308 
5309         RTList.push_back(CGT.ConvertType(b->getType()));
5310       }
5311 
5312       if (b == e)
5313         return llvm::StructType::get(getVMContext(), RTList,
5314                                      RD->hasAttr<PackedAttr>());
5315 
5316       RTList.clear();
5317     }
5318   }
5319 
5320   CoerceToIntArgs(Size, RTList);
5321   return llvm::StructType::get(getVMContext(), RTList);
5322 }
5323 
5324 ABIArgInfo MipsABIInfo::classifyReturnType(QualType RetTy) const {
5325   uint64_t Size = getContext().getTypeSize(RetTy);
5326 
5327   if (RetTy->isVoidType() || Size == 0)
5328     return ABIArgInfo::getIgnore();
5329 
5330   if (isAggregateTypeForABI(RetTy) || RetTy->isVectorType()) {
5331     if (Size <= 128) {
5332       if (RetTy->isAnyComplexType())
5333         return ABIArgInfo::getDirect();
5334 
5335       // O32 returns integer vectors in registers.
5336       if (IsO32 && RetTy->isVectorType() && !RetTy->hasFloatingRepresentation())
5337         return ABIArgInfo::getDirect(returnAggregateInRegs(RetTy, Size));
5338 
5339       if (!IsO32)
5340         return ABIArgInfo::getDirect(returnAggregateInRegs(RetTy, Size));
5341     }
5342 
5343     return ABIArgInfo::getIndirect(0);
5344   }
5345 
5346   // Treat an enum type as its underlying type.
5347   if (const EnumType *EnumTy = RetTy->getAs<EnumType>())
5348     RetTy = EnumTy->getDecl()->getIntegerType();
5349 
5350   return (RetTy->isPromotableIntegerType() ?
5351           ABIArgInfo::getExtend() : ABIArgInfo::getDirect());
5352 }
5353 
5354 void MipsABIInfo::computeInfo(CGFunctionInfo &FI) const {
5355   ABIArgInfo &RetInfo = FI.getReturnInfo();
5356   if (!getCXXABI().classifyReturnType(FI))
5357     RetInfo = classifyReturnType(FI.getReturnType());
5358 
5359   // Check if a pointer to an aggregate is passed as a hidden argument.
5360   uint64_t Offset = RetInfo.isIndirect() ? MinABIStackAlignInBytes : 0;
5361 
5362   for (auto &I : FI.arguments())
5363     I.info = classifyArgumentType(I.type, Offset);
5364 }
5365 
5366 llvm::Value* MipsABIInfo::EmitVAArg(llvm::Value *VAListAddr, QualType Ty,
5367                                     CodeGenFunction &CGF) const {
5368   llvm::Type *BP = CGF.Int8PtrTy;
5369   llvm::Type *BPP = CGF.Int8PtrPtrTy;
5370 
5371   CGBuilderTy &Builder = CGF.Builder;
5372   llvm::Value *VAListAddrAsBPP = Builder.CreateBitCast(VAListAddr, BPP, "ap");
5373   llvm::Value *Addr = Builder.CreateLoad(VAListAddrAsBPP, "ap.cur");
5374   int64_t TypeAlign = getContext().getTypeAlign(Ty) / 8;
5375   llvm::Type *PTy = llvm::PointerType::getUnqual(CGF.ConvertType(Ty));
5376   llvm::Value *AddrTyped;
5377   unsigned PtrWidth = getTarget().getPointerWidth(0);
5378   llvm::IntegerType *IntTy = (PtrWidth == 32) ? CGF.Int32Ty : CGF.Int64Ty;
5379 
5380   if (TypeAlign > MinABIStackAlignInBytes) {
5381     llvm::Value *AddrAsInt = CGF.Builder.CreatePtrToInt(Addr, IntTy);
5382     llvm::Value *Inc = llvm::ConstantInt::get(IntTy, TypeAlign - 1);
5383     llvm::Value *Mask = llvm::ConstantInt::get(IntTy, -TypeAlign);
5384     llvm::Value *Add = CGF.Builder.CreateAdd(AddrAsInt, Inc);
5385     llvm::Value *And = CGF.Builder.CreateAnd(Add, Mask);
5386     AddrTyped = CGF.Builder.CreateIntToPtr(And, PTy);
5387   }
5388   else
5389     AddrTyped = Builder.CreateBitCast(Addr, PTy);
5390 
5391   llvm::Value *AlignedAddr = Builder.CreateBitCast(AddrTyped, BP);
5392   TypeAlign = std::max((unsigned)TypeAlign, MinABIStackAlignInBytes);
5393   uint64_t Offset =
5394     llvm::RoundUpToAlignment(CGF.getContext().getTypeSize(Ty) / 8, TypeAlign);
5395   llvm::Value *NextAddr =
5396     Builder.CreateGEP(AlignedAddr, llvm::ConstantInt::get(IntTy, Offset),
5397                       "ap.next");
5398   Builder.CreateStore(NextAddr, VAListAddrAsBPP);
5399 
5400   return AddrTyped;
5401 }
5402 
5403 bool
5404 MIPSTargetCodeGenInfo::initDwarfEHRegSizeTable(CodeGen::CodeGenFunction &CGF,
5405                                                llvm::Value *Address) const {
5406   // This information comes from gcc's implementation, which seems to
5407   // as canonical as it gets.
5408 
5409   // Everything on MIPS is 4 bytes.  Double-precision FP registers
5410   // are aliased to pairs of single-precision FP registers.
5411   llvm::Value *Four8 = llvm::ConstantInt::get(CGF.Int8Ty, 4);
5412 
5413   // 0-31 are the general purpose registers, $0 - $31.
5414   // 32-63 are the floating-point registers, $f0 - $f31.
5415   // 64 and 65 are the multiply/divide registers, $hi and $lo.
5416   // 66 is the (notional, I think) register for signal-handler return.
5417   AssignToArrayRange(CGF.Builder, Address, Four8, 0, 65);
5418 
5419   // 67-74 are the floating-point status registers, $fcc0 - $fcc7.
5420   // They are one bit wide and ignored here.
5421 
5422   // 80-111 are the coprocessor 0 registers, $c0r0 - $c0r31.
5423   // (coprocessor 1 is the FP unit)
5424   // 112-143 are the coprocessor 2 registers, $c2r0 - $c2r31.
5425   // 144-175 are the coprocessor 3 registers, $c3r0 - $c3r31.
5426   // 176-181 are the DSP accumulator registers.
5427   AssignToArrayRange(CGF.Builder, Address, Four8, 80, 181);
5428   return false;
5429 }
5430 
5431 //===----------------------------------------------------------------------===//
5432 // TCE ABI Implementation (see http://tce.cs.tut.fi). Uses mostly the defaults.
5433 // Currently subclassed only to implement custom OpenCL C function attribute
5434 // handling.
5435 //===----------------------------------------------------------------------===//
5436 
5437 namespace {
5438 
5439 class TCETargetCodeGenInfo : public DefaultTargetCodeGenInfo {
5440 public:
5441   TCETargetCodeGenInfo(CodeGenTypes &CGT)
5442     : DefaultTargetCodeGenInfo(CGT) {}
5443 
5444   void SetTargetAttributes(const Decl *D, llvm::GlobalValue *GV,
5445                            CodeGen::CodeGenModule &M) const override;
5446 };
5447 
5448 void TCETargetCodeGenInfo::SetTargetAttributes(const Decl *D,
5449                                                llvm::GlobalValue *GV,
5450                                                CodeGen::CodeGenModule &M) const {
5451   const FunctionDecl *FD = dyn_cast<FunctionDecl>(D);
5452   if (!FD) return;
5453 
5454   llvm::Function *F = cast<llvm::Function>(GV);
5455 
5456   if (M.getLangOpts().OpenCL) {
5457     if (FD->hasAttr<OpenCLKernelAttr>()) {
5458       // OpenCL C Kernel functions are not subject to inlining
5459       F->addFnAttr(llvm::Attribute::NoInline);
5460       const ReqdWorkGroupSizeAttr *Attr = FD->getAttr<ReqdWorkGroupSizeAttr>();
5461       if (Attr) {
5462         // Convert the reqd_work_group_size() attributes to metadata.
5463         llvm::LLVMContext &Context = F->getContext();
5464         llvm::NamedMDNode *OpenCLMetadata =
5465             M.getModule().getOrInsertNamedMetadata("opencl.kernel_wg_size_info");
5466 
5467         SmallVector<llvm::Value*, 5> Operands;
5468         Operands.push_back(F);
5469 
5470         Operands.push_back(llvm::Constant::getIntegerValue(M.Int32Ty,
5471                              llvm::APInt(32, Attr->getXDim())));
5472         Operands.push_back(llvm::Constant::getIntegerValue(M.Int32Ty,
5473                              llvm::APInt(32, Attr->getYDim())));
5474         Operands.push_back(llvm::Constant::getIntegerValue(M.Int32Ty,
5475                              llvm::APInt(32, Attr->getZDim())));
5476 
5477         // Add a boolean constant operand for "required" (true) or "hint" (false)
5478         // for implementing the work_group_size_hint attr later. Currently
5479         // always true as the hint is not yet implemented.
5480         Operands.push_back(llvm::ConstantInt::getTrue(Context));
5481         OpenCLMetadata->addOperand(llvm::MDNode::get(Context, Operands));
5482       }
5483     }
5484   }
5485 }
5486 
5487 }
5488 
5489 //===----------------------------------------------------------------------===//
5490 // Hexagon ABI Implementation
5491 //===----------------------------------------------------------------------===//
5492 
5493 namespace {
5494 
5495 class HexagonABIInfo : public ABIInfo {
5496 
5497 
5498 public:
5499   HexagonABIInfo(CodeGenTypes &CGT) : ABIInfo(CGT) {}
5500 
5501 private:
5502 
5503   ABIArgInfo classifyReturnType(QualType RetTy) const;
5504   ABIArgInfo classifyArgumentType(QualType RetTy) const;
5505 
5506   void computeInfo(CGFunctionInfo &FI) const override;
5507 
5508   llvm::Value *EmitVAArg(llvm::Value *VAListAddr, QualType Ty,
5509                          CodeGenFunction &CGF) const override;
5510 };
5511 
5512 class HexagonTargetCodeGenInfo : public TargetCodeGenInfo {
5513 public:
5514   HexagonTargetCodeGenInfo(CodeGenTypes &CGT)
5515     :TargetCodeGenInfo(new HexagonABIInfo(CGT)) {}
5516 
5517   int getDwarfEHStackPointer(CodeGen::CodeGenModule &M) const override {
5518     return 29;
5519   }
5520 };
5521 
5522 }
5523 
5524 void HexagonABIInfo::computeInfo(CGFunctionInfo &FI) const {
5525   if (!getCXXABI().classifyReturnType(FI))
5526     FI.getReturnInfo() = classifyReturnType(FI.getReturnType());
5527   for (auto &I : FI.arguments())
5528     I.info = classifyArgumentType(I.type);
5529 }
5530 
5531 ABIArgInfo HexagonABIInfo::classifyArgumentType(QualType Ty) const {
5532   if (!isAggregateTypeForABI(Ty)) {
5533     // Treat an enum type as its underlying type.
5534     if (const EnumType *EnumTy = Ty->getAs<EnumType>())
5535       Ty = EnumTy->getDecl()->getIntegerType();
5536 
5537     return (Ty->isPromotableIntegerType() ?
5538             ABIArgInfo::getExtend() : ABIArgInfo::getDirect());
5539   }
5540 
5541   // Ignore empty records.
5542   if (isEmptyRecord(getContext(), Ty, true))
5543     return ABIArgInfo::getIgnore();
5544 
5545   if (CGCXXABI::RecordArgABI RAA = getRecordArgABI(Ty, getCXXABI()))
5546     return ABIArgInfo::getIndirect(0, RAA == CGCXXABI::RAA_DirectInMemory);
5547 
5548   uint64_t Size = getContext().getTypeSize(Ty);
5549   if (Size > 64)
5550     return ABIArgInfo::getIndirect(0, /*ByVal=*/true);
5551     // Pass in the smallest viable integer type.
5552   else if (Size > 32)
5553       return ABIArgInfo::getDirect(llvm::Type::getInt64Ty(getVMContext()));
5554   else if (Size > 16)
5555       return ABIArgInfo::getDirect(llvm::Type::getInt32Ty(getVMContext()));
5556   else if (Size > 8)
5557       return ABIArgInfo::getDirect(llvm::Type::getInt16Ty(getVMContext()));
5558   else
5559       return ABIArgInfo::getDirect(llvm::Type::getInt8Ty(getVMContext()));
5560 }
5561 
5562 ABIArgInfo HexagonABIInfo::classifyReturnType(QualType RetTy) const {
5563   if (RetTy->isVoidType())
5564     return ABIArgInfo::getIgnore();
5565 
5566   // Large vector types should be returned via memory.
5567   if (RetTy->isVectorType() && getContext().getTypeSize(RetTy) > 64)
5568     return ABIArgInfo::getIndirect(0);
5569 
5570   if (!isAggregateTypeForABI(RetTy)) {
5571     // Treat an enum type as its underlying type.
5572     if (const EnumType *EnumTy = RetTy->getAs<EnumType>())
5573       RetTy = EnumTy->getDecl()->getIntegerType();
5574 
5575     return (RetTy->isPromotableIntegerType() ?
5576             ABIArgInfo::getExtend() : ABIArgInfo::getDirect());
5577   }
5578 
5579   if (isEmptyRecord(getContext(), RetTy, true))
5580     return ABIArgInfo::getIgnore();
5581 
5582   // Aggregates <= 8 bytes are returned in r0; other aggregates
5583   // are returned indirectly.
5584   uint64_t Size = getContext().getTypeSize(RetTy);
5585   if (Size <= 64) {
5586     // Return in the smallest viable integer type.
5587     if (Size <= 8)
5588       return ABIArgInfo::getDirect(llvm::Type::getInt8Ty(getVMContext()));
5589     if (Size <= 16)
5590       return ABIArgInfo::getDirect(llvm::Type::getInt16Ty(getVMContext()));
5591     if (Size <= 32)
5592       return ABIArgInfo::getDirect(llvm::Type::getInt32Ty(getVMContext()));
5593     return ABIArgInfo::getDirect(llvm::Type::getInt64Ty(getVMContext()));
5594   }
5595 
5596   return ABIArgInfo::getIndirect(0, /*ByVal=*/true);
5597 }
5598 
5599 llvm::Value *HexagonABIInfo::EmitVAArg(llvm::Value *VAListAddr, QualType Ty,
5600                                        CodeGenFunction &CGF) const {
5601   // FIXME: Need to handle alignment
5602   llvm::Type *BPP = CGF.Int8PtrPtrTy;
5603 
5604   CGBuilderTy &Builder = CGF.Builder;
5605   llvm::Value *VAListAddrAsBPP = Builder.CreateBitCast(VAListAddr, BPP,
5606                                                        "ap");
5607   llvm::Value *Addr = Builder.CreateLoad(VAListAddrAsBPP, "ap.cur");
5608   llvm::Type *PTy =
5609     llvm::PointerType::getUnqual(CGF.ConvertType(Ty));
5610   llvm::Value *AddrTyped = Builder.CreateBitCast(Addr, PTy);
5611 
5612   uint64_t Offset =
5613     llvm::RoundUpToAlignment(CGF.getContext().getTypeSize(Ty) / 8, 4);
5614   llvm::Value *NextAddr =
5615     Builder.CreateGEP(Addr, llvm::ConstantInt::get(CGF.Int32Ty, Offset),
5616                       "ap.next");
5617   Builder.CreateStore(NextAddr, VAListAddrAsBPP);
5618 
5619   return AddrTyped;
5620 }
5621 
5622 
5623 //===----------------------------------------------------------------------===//
5624 // SPARC v9 ABI Implementation.
5625 // Based on the SPARC Compliance Definition version 2.4.1.
5626 //
5627 // Function arguments a mapped to a nominal "parameter array" and promoted to
5628 // registers depending on their type. Each argument occupies 8 or 16 bytes in
5629 // the array, structs larger than 16 bytes are passed indirectly.
5630 //
5631 // One case requires special care:
5632 //
5633 //   struct mixed {
5634 //     int i;
5635 //     float f;
5636 //   };
5637 //
5638 // When a struct mixed is passed by value, it only occupies 8 bytes in the
5639 // parameter array, but the int is passed in an integer register, and the float
5640 // is passed in a floating point register. This is represented as two arguments
5641 // with the LLVM IR inreg attribute:
5642 //
5643 //   declare void f(i32 inreg %i, float inreg %f)
5644 //
5645 // The code generator will only allocate 4 bytes from the parameter array for
5646 // the inreg arguments. All other arguments are allocated a multiple of 8
5647 // bytes.
5648 //
5649 namespace {
5650 class SparcV9ABIInfo : public ABIInfo {
5651 public:
5652   SparcV9ABIInfo(CodeGenTypes &CGT) : ABIInfo(CGT) {}
5653 
5654 private:
5655   ABIArgInfo classifyType(QualType RetTy, unsigned SizeLimit) const;
5656   void computeInfo(CGFunctionInfo &FI) const override;
5657   llvm::Value *EmitVAArg(llvm::Value *VAListAddr, QualType Ty,
5658                          CodeGenFunction &CGF) const override;
5659 
5660   // Coercion type builder for structs passed in registers. The coercion type
5661   // serves two purposes:
5662   //
5663   // 1. Pad structs to a multiple of 64 bits, so they are passed 'left-aligned'
5664   //    in registers.
5665   // 2. Expose aligned floating point elements as first-level elements, so the
5666   //    code generator knows to pass them in floating point registers.
5667   //
5668   // We also compute the InReg flag which indicates that the struct contains
5669   // aligned 32-bit floats.
5670   //
5671   struct CoerceBuilder {
5672     llvm::LLVMContext &Context;
5673     const llvm::DataLayout &DL;
5674     SmallVector<llvm::Type*, 8> Elems;
5675     uint64_t Size;
5676     bool InReg;
5677 
5678     CoerceBuilder(llvm::LLVMContext &c, const llvm::DataLayout &dl)
5679       : Context(c), DL(dl), Size(0), InReg(false) {}
5680 
5681     // Pad Elems with integers until Size is ToSize.
5682     void pad(uint64_t ToSize) {
5683       assert(ToSize >= Size && "Cannot remove elements");
5684       if (ToSize == Size)
5685         return;
5686 
5687       // Finish the current 64-bit word.
5688       uint64_t Aligned = llvm::RoundUpToAlignment(Size, 64);
5689       if (Aligned > Size && Aligned <= ToSize) {
5690         Elems.push_back(llvm::IntegerType::get(Context, Aligned - Size));
5691         Size = Aligned;
5692       }
5693 
5694       // Add whole 64-bit words.
5695       while (Size + 64 <= ToSize) {
5696         Elems.push_back(llvm::Type::getInt64Ty(Context));
5697         Size += 64;
5698       }
5699 
5700       // Final in-word padding.
5701       if (Size < ToSize) {
5702         Elems.push_back(llvm::IntegerType::get(Context, ToSize - Size));
5703         Size = ToSize;
5704       }
5705     }
5706 
5707     // Add a floating point element at Offset.
5708     void addFloat(uint64_t Offset, llvm::Type *Ty, unsigned Bits) {
5709       // Unaligned floats are treated as integers.
5710       if (Offset % Bits)
5711         return;
5712       // The InReg flag is only required if there are any floats < 64 bits.
5713       if (Bits < 64)
5714         InReg = true;
5715       pad(Offset);
5716       Elems.push_back(Ty);
5717       Size = Offset + Bits;
5718     }
5719 
5720     // Add a struct type to the coercion type, starting at Offset (in bits).
5721     void addStruct(uint64_t Offset, llvm::StructType *StrTy) {
5722       const llvm::StructLayout *Layout = DL.getStructLayout(StrTy);
5723       for (unsigned i = 0, e = StrTy->getNumElements(); i != e; ++i) {
5724         llvm::Type *ElemTy = StrTy->getElementType(i);
5725         uint64_t ElemOffset = Offset + Layout->getElementOffsetInBits(i);
5726         switch (ElemTy->getTypeID()) {
5727         case llvm::Type::StructTyID:
5728           addStruct(ElemOffset, cast<llvm::StructType>(ElemTy));
5729           break;
5730         case llvm::Type::FloatTyID:
5731           addFloat(ElemOffset, ElemTy, 32);
5732           break;
5733         case llvm::Type::DoubleTyID:
5734           addFloat(ElemOffset, ElemTy, 64);
5735           break;
5736         case llvm::Type::FP128TyID:
5737           addFloat(ElemOffset, ElemTy, 128);
5738           break;
5739         case llvm::Type::PointerTyID:
5740           if (ElemOffset % 64 == 0) {
5741             pad(ElemOffset);
5742             Elems.push_back(ElemTy);
5743             Size += 64;
5744           }
5745           break;
5746         default:
5747           break;
5748         }
5749       }
5750     }
5751 
5752     // Check if Ty is a usable substitute for the coercion type.
5753     bool isUsableType(llvm::StructType *Ty) const {
5754       if (Ty->getNumElements() != Elems.size())
5755         return false;
5756       for (unsigned i = 0, e = Elems.size(); i != e; ++i)
5757         if (Elems[i] != Ty->getElementType(i))
5758           return false;
5759       return true;
5760     }
5761 
5762     // Get the coercion type as a literal struct type.
5763     llvm::Type *getType() const {
5764       if (Elems.size() == 1)
5765         return Elems.front();
5766       else
5767         return llvm::StructType::get(Context, Elems);
5768     }
5769   };
5770 };
5771 } // end anonymous namespace
5772 
5773 ABIArgInfo
5774 SparcV9ABIInfo::classifyType(QualType Ty, unsigned SizeLimit) const {
5775   if (Ty->isVoidType())
5776     return ABIArgInfo::getIgnore();
5777 
5778   uint64_t Size = getContext().getTypeSize(Ty);
5779 
5780   // Anything too big to fit in registers is passed with an explicit indirect
5781   // pointer / sret pointer.
5782   if (Size > SizeLimit)
5783     return ABIArgInfo::getIndirect(0, /*ByVal=*/false);
5784 
5785   // Treat an enum type as its underlying type.
5786   if (const EnumType *EnumTy = Ty->getAs<EnumType>())
5787     Ty = EnumTy->getDecl()->getIntegerType();
5788 
5789   // Integer types smaller than a register are extended.
5790   if (Size < 64 && Ty->isIntegerType())
5791     return ABIArgInfo::getExtend();
5792 
5793   // Other non-aggregates go in registers.
5794   if (!isAggregateTypeForABI(Ty))
5795     return ABIArgInfo::getDirect();
5796 
5797   // If a C++ object has either a non-trivial copy constructor or a non-trivial
5798   // destructor, it is passed with an explicit indirect pointer / sret pointer.
5799   if (CGCXXABI::RecordArgABI RAA = getRecordArgABI(Ty, getCXXABI()))
5800     return ABIArgInfo::getIndirect(0, RAA == CGCXXABI::RAA_DirectInMemory);
5801 
5802   // This is a small aggregate type that should be passed in registers.
5803   // Build a coercion type from the LLVM struct type.
5804   llvm::StructType *StrTy = dyn_cast<llvm::StructType>(CGT.ConvertType(Ty));
5805   if (!StrTy)
5806     return ABIArgInfo::getDirect();
5807 
5808   CoerceBuilder CB(getVMContext(), getDataLayout());
5809   CB.addStruct(0, StrTy);
5810   CB.pad(llvm::RoundUpToAlignment(CB.DL.getTypeSizeInBits(StrTy), 64));
5811 
5812   // Try to use the original type for coercion.
5813   llvm::Type *CoerceTy = CB.isUsableType(StrTy) ? StrTy : CB.getType();
5814 
5815   if (CB.InReg)
5816     return ABIArgInfo::getDirectInReg(CoerceTy);
5817   else
5818     return ABIArgInfo::getDirect(CoerceTy);
5819 }
5820 
5821 llvm::Value *SparcV9ABIInfo::EmitVAArg(llvm::Value *VAListAddr, QualType Ty,
5822                                        CodeGenFunction &CGF) const {
5823   ABIArgInfo AI = classifyType(Ty, 16 * 8);
5824   llvm::Type *ArgTy = CGT.ConvertType(Ty);
5825   if (AI.canHaveCoerceToType() && !AI.getCoerceToType())
5826     AI.setCoerceToType(ArgTy);
5827 
5828   llvm::Type *BPP = CGF.Int8PtrPtrTy;
5829   CGBuilderTy &Builder = CGF.Builder;
5830   llvm::Value *VAListAddrAsBPP = Builder.CreateBitCast(VAListAddr, BPP, "ap");
5831   llvm::Value *Addr = Builder.CreateLoad(VAListAddrAsBPP, "ap.cur");
5832   llvm::Type *ArgPtrTy = llvm::PointerType::getUnqual(ArgTy);
5833   llvm::Value *ArgAddr;
5834   unsigned Stride;
5835 
5836   switch (AI.getKind()) {
5837   case ABIArgInfo::Expand:
5838   case ABIArgInfo::InAlloca:
5839     llvm_unreachable("Unsupported ABI kind for va_arg");
5840 
5841   case ABIArgInfo::Extend:
5842     Stride = 8;
5843     ArgAddr = Builder
5844       .CreateConstGEP1_32(Addr, 8 - getDataLayout().getTypeAllocSize(ArgTy),
5845                           "extend");
5846     break;
5847 
5848   case ABIArgInfo::Direct:
5849     Stride = getDataLayout().getTypeAllocSize(AI.getCoerceToType());
5850     ArgAddr = Addr;
5851     break;
5852 
5853   case ABIArgInfo::Indirect:
5854     Stride = 8;
5855     ArgAddr = Builder.CreateBitCast(Addr,
5856                                     llvm::PointerType::getUnqual(ArgPtrTy),
5857                                     "indirect");
5858     ArgAddr = Builder.CreateLoad(ArgAddr, "indirect.arg");
5859     break;
5860 
5861   case ABIArgInfo::Ignore:
5862     return llvm::UndefValue::get(ArgPtrTy);
5863   }
5864 
5865   // Update VAList.
5866   Addr = Builder.CreateConstGEP1_32(Addr, Stride, "ap.next");
5867   Builder.CreateStore(Addr, VAListAddrAsBPP);
5868 
5869   return Builder.CreatePointerCast(ArgAddr, ArgPtrTy, "arg.addr");
5870 }
5871 
5872 void SparcV9ABIInfo::computeInfo(CGFunctionInfo &FI) const {
5873   FI.getReturnInfo() = classifyType(FI.getReturnType(), 32 * 8);
5874   for (auto &I : FI.arguments())
5875     I.info = classifyType(I.type, 16 * 8);
5876 }
5877 
5878 namespace {
5879 class SparcV9TargetCodeGenInfo : public TargetCodeGenInfo {
5880 public:
5881   SparcV9TargetCodeGenInfo(CodeGenTypes &CGT)
5882     : TargetCodeGenInfo(new SparcV9ABIInfo(CGT)) {}
5883 
5884   int getDwarfEHStackPointer(CodeGen::CodeGenModule &M) const override {
5885     return 14;
5886   }
5887 
5888   bool initDwarfEHRegSizeTable(CodeGen::CodeGenFunction &CGF,
5889                                llvm::Value *Address) const override;
5890 };
5891 } // end anonymous namespace
5892 
5893 bool
5894 SparcV9TargetCodeGenInfo::initDwarfEHRegSizeTable(CodeGen::CodeGenFunction &CGF,
5895                                                 llvm::Value *Address) const {
5896   // This is calculated from the LLVM and GCC tables and verified
5897   // against gcc output.  AFAIK all ABIs use the same encoding.
5898 
5899   CodeGen::CGBuilderTy &Builder = CGF.Builder;
5900 
5901   llvm::IntegerType *i8 = CGF.Int8Ty;
5902   llvm::Value *Four8 = llvm::ConstantInt::get(i8, 4);
5903   llvm::Value *Eight8 = llvm::ConstantInt::get(i8, 8);
5904 
5905   // 0-31: the 8-byte general-purpose registers
5906   AssignToArrayRange(Builder, Address, Eight8, 0, 31);
5907 
5908   // 32-63: f0-31, the 4-byte floating-point registers
5909   AssignToArrayRange(Builder, Address, Four8, 32, 63);
5910 
5911   //   Y   = 64
5912   //   PSR = 65
5913   //   WIM = 66
5914   //   TBR = 67
5915   //   PC  = 68
5916   //   NPC = 69
5917   //   FSR = 70
5918   //   CSR = 71
5919   AssignToArrayRange(Builder, Address, Eight8, 64, 71);
5920 
5921   // 72-87: d0-15, the 8-byte floating-point registers
5922   AssignToArrayRange(Builder, Address, Eight8, 72, 87);
5923 
5924   return false;
5925 }
5926 
5927 
5928 //===----------------------------------------------------------------------===//
5929 // XCore ABI Implementation
5930 //===----------------------------------------------------------------------===//
5931 
5932 namespace {
5933 
5934 /// A SmallStringEnc instance is used to build up the TypeString by passing
5935 /// it by reference between functions that append to it.
5936 typedef llvm::SmallString<128> SmallStringEnc;
5937 
5938 /// TypeStringCache caches the meta encodings of Types.
5939 ///
5940 /// The reason for caching TypeStrings is two fold:
5941 ///   1. To cache a type's encoding for later uses;
5942 ///   2. As a means to break recursive member type inclusion.
5943 ///
5944 /// A cache Entry can have a Status of:
5945 ///   NonRecursive:   The type encoding is not recursive;
5946 ///   Recursive:      The type encoding is recursive;
5947 ///   Incomplete:     An incomplete TypeString;
5948 ///   IncompleteUsed: An incomplete TypeString that has been used in a
5949 ///                   Recursive type encoding.
5950 ///
5951 /// A NonRecursive entry will have all of its sub-members expanded as fully
5952 /// as possible. Whilst it may contain types which are recursive, the type
5953 /// itself is not recursive and thus its encoding may be safely used whenever
5954 /// the type is encountered.
5955 ///
5956 /// A Recursive entry will have all of its sub-members expanded as fully as
5957 /// possible. The type itself is recursive and it may contain other types which
5958 /// are recursive. The Recursive encoding must not be used during the expansion
5959 /// of a recursive type's recursive branch. For simplicity the code uses
5960 /// IncompleteCount to reject all usage of Recursive encodings for member types.
5961 ///
5962 /// An Incomplete entry is always a RecordType and only encodes its
5963 /// identifier e.g. "s(S){}". Incomplete 'StubEnc' entries are ephemeral and
5964 /// are placed into the cache during type expansion as a means to identify and
5965 /// handle recursive inclusion of types as sub-members. If there is recursion
5966 /// the entry becomes IncompleteUsed.
5967 ///
5968 /// During the expansion of a RecordType's members:
5969 ///
5970 ///   If the cache contains a NonRecursive encoding for the member type, the
5971 ///   cached encoding is used;
5972 ///
5973 ///   If the cache contains a Recursive encoding for the member type, the
5974 ///   cached encoding is 'Swapped' out, as it may be incorrect, and...
5975 ///
5976 ///   If the member is a RecordType, an Incomplete encoding is placed into the
5977 ///   cache to break potential recursive inclusion of itself as a sub-member;
5978 ///
5979 ///   Once a member RecordType has been expanded, its temporary incomplete
5980 ///   entry is removed from the cache. If a Recursive encoding was swapped out
5981 ///   it is swapped back in;
5982 ///
5983 ///   If an incomplete entry is used to expand a sub-member, the incomplete
5984 ///   entry is marked as IncompleteUsed. The cache keeps count of how many
5985 ///   IncompleteUsed entries it currently contains in IncompleteUsedCount;
5986 ///
5987 ///   If a member's encoding is found to be a NonRecursive or Recursive viz:
5988 ///   IncompleteUsedCount==0, the member's encoding is added to the cache.
5989 ///   Else the member is part of a recursive type and thus the recursion has
5990 ///   been exited too soon for the encoding to be correct for the member.
5991 ///
5992 class TypeStringCache {
5993   enum Status {NonRecursive, Recursive, Incomplete, IncompleteUsed};
5994   struct Entry {
5995     std::string Str;     // The encoded TypeString for the type.
5996     enum Status State;   // Information about the encoding in 'Str'.
5997     std::string Swapped; // A temporary place holder for a Recursive encoding
5998                          // during the expansion of RecordType's members.
5999   };
6000   std::map<const IdentifierInfo *, struct Entry> Map;
6001   unsigned IncompleteCount;     // Number of Incomplete entries in the Map.
6002   unsigned IncompleteUsedCount; // Number of IncompleteUsed entries in the Map.
6003 public:
6004   TypeStringCache() : IncompleteCount(0), IncompleteUsedCount(0) {};
6005   void addIncomplete(const IdentifierInfo *ID, std::string StubEnc);
6006   bool removeIncomplete(const IdentifierInfo *ID);
6007   void addIfComplete(const IdentifierInfo *ID, StringRef Str,
6008                      bool IsRecursive);
6009   StringRef lookupStr(const IdentifierInfo *ID);
6010 };
6011 
6012 /// TypeString encodings for enum & union fields must be order.
6013 /// FieldEncoding is a helper for this ordering process.
6014 class FieldEncoding {
6015   bool HasName;
6016   std::string Enc;
6017 public:
6018   FieldEncoding(bool b, SmallStringEnc &e) : HasName(b), Enc(e.c_str()) {};
6019   StringRef str() {return Enc.c_str();};
6020   bool operator<(const FieldEncoding &rhs) const {
6021     if (HasName != rhs.HasName) return HasName;
6022     return Enc < rhs.Enc;
6023   }
6024 };
6025 
6026 class XCoreABIInfo : public DefaultABIInfo {
6027 public:
6028   XCoreABIInfo(CodeGen::CodeGenTypes &CGT) : DefaultABIInfo(CGT) {}
6029   llvm::Value *EmitVAArg(llvm::Value *VAListAddr, QualType Ty,
6030                          CodeGenFunction &CGF) const override;
6031 };
6032 
6033 class XCoreTargetCodeGenInfo : public TargetCodeGenInfo {
6034   mutable TypeStringCache TSC;
6035 public:
6036   XCoreTargetCodeGenInfo(CodeGenTypes &CGT)
6037     :TargetCodeGenInfo(new XCoreABIInfo(CGT)) {}
6038   void emitTargetMD(const Decl *D, llvm::GlobalValue *GV,
6039                     CodeGen::CodeGenModule &M) const override;
6040 };
6041 
6042 } // End anonymous namespace.
6043 
6044 llvm::Value *XCoreABIInfo::EmitVAArg(llvm::Value *VAListAddr, QualType Ty,
6045                                      CodeGenFunction &CGF) const {
6046   CGBuilderTy &Builder = CGF.Builder;
6047 
6048   // Get the VAList.
6049   llvm::Value *VAListAddrAsBPP = Builder.CreateBitCast(VAListAddr,
6050                                                        CGF.Int8PtrPtrTy);
6051   llvm::Value *AP = Builder.CreateLoad(VAListAddrAsBPP);
6052 
6053   // Handle the argument.
6054   ABIArgInfo AI = classifyArgumentType(Ty);
6055   llvm::Type *ArgTy = CGT.ConvertType(Ty);
6056   if (AI.canHaveCoerceToType() && !AI.getCoerceToType())
6057     AI.setCoerceToType(ArgTy);
6058   llvm::Type *ArgPtrTy = llvm::PointerType::getUnqual(ArgTy);
6059   llvm::Value *Val;
6060   uint64_t ArgSize = 0;
6061   switch (AI.getKind()) {
6062   case ABIArgInfo::Expand:
6063   case ABIArgInfo::InAlloca:
6064     llvm_unreachable("Unsupported ABI kind for va_arg");
6065   case ABIArgInfo::Ignore:
6066     Val = llvm::UndefValue::get(ArgPtrTy);
6067     ArgSize = 0;
6068     break;
6069   case ABIArgInfo::Extend:
6070   case ABIArgInfo::Direct:
6071     Val = Builder.CreatePointerCast(AP, ArgPtrTy);
6072     ArgSize = getDataLayout().getTypeAllocSize(AI.getCoerceToType());
6073     if (ArgSize < 4)
6074       ArgSize = 4;
6075     break;
6076   case ABIArgInfo::Indirect:
6077     llvm::Value *ArgAddr;
6078     ArgAddr = Builder.CreateBitCast(AP, llvm::PointerType::getUnqual(ArgPtrTy));
6079     ArgAddr = Builder.CreateLoad(ArgAddr);
6080     Val = Builder.CreatePointerCast(ArgAddr, ArgPtrTy);
6081     ArgSize = 4;
6082     break;
6083   }
6084 
6085   // Increment the VAList.
6086   if (ArgSize) {
6087     llvm::Value *APN = Builder.CreateConstGEP1_32(AP, ArgSize);
6088     Builder.CreateStore(APN, VAListAddrAsBPP);
6089   }
6090   return Val;
6091 }
6092 
6093 /// During the expansion of a RecordType, an incomplete TypeString is placed
6094 /// into the cache as a means to identify and break recursion.
6095 /// If there is a Recursive encoding in the cache, it is swapped out and will
6096 /// be reinserted by removeIncomplete().
6097 /// All other types of encoding should have been used rather than arriving here.
6098 void TypeStringCache::addIncomplete(const IdentifierInfo *ID,
6099                                     std::string StubEnc) {
6100   if (!ID)
6101     return;
6102   Entry &E = Map[ID];
6103   assert( (E.Str.empty() || E.State == Recursive) &&
6104          "Incorrectly use of addIncomplete");
6105   assert(!StubEnc.empty() && "Passing an empty string to addIncomplete()");
6106   E.Swapped.swap(E.Str); // swap out the Recursive
6107   E.Str.swap(StubEnc);
6108   E.State = Incomplete;
6109   ++IncompleteCount;
6110 }
6111 
6112 /// Once the RecordType has been expanded, the temporary incomplete TypeString
6113 /// must be removed from the cache.
6114 /// If a Recursive was swapped out by addIncomplete(), it will be replaced.
6115 /// Returns true if the RecordType was defined recursively.
6116 bool TypeStringCache::removeIncomplete(const IdentifierInfo *ID) {
6117   if (!ID)
6118     return false;
6119   auto I = Map.find(ID);
6120   assert(I != Map.end() && "Entry not present");
6121   Entry &E = I->second;
6122   assert( (E.State == Incomplete ||
6123            E.State == IncompleteUsed) &&
6124          "Entry must be an incomplete type");
6125   bool IsRecursive = false;
6126   if (E.State == IncompleteUsed) {
6127     // We made use of our Incomplete encoding, thus we are recursive.
6128     IsRecursive = true;
6129     --IncompleteUsedCount;
6130   }
6131   if (E.Swapped.empty())
6132     Map.erase(I);
6133   else {
6134     // Swap the Recursive back.
6135     E.Swapped.swap(E.Str);
6136     E.Swapped.clear();
6137     E.State = Recursive;
6138   }
6139   --IncompleteCount;
6140   return IsRecursive;
6141 }
6142 
6143 /// Add the encoded TypeString to the cache only if it is NonRecursive or
6144 /// Recursive (viz: all sub-members were expanded as fully as possible).
6145 void TypeStringCache::addIfComplete(const IdentifierInfo *ID, StringRef Str,
6146                                     bool IsRecursive) {
6147   if (!ID || IncompleteUsedCount)
6148     return; // No key or it is is an incomplete sub-type so don't add.
6149   Entry &E = Map[ID];
6150   if (IsRecursive && !E.Str.empty()) {
6151     assert(E.State==Recursive && E.Str.size() == Str.size() &&
6152            "This is not the same Recursive entry");
6153     // The parent container was not recursive after all, so we could have used
6154     // this Recursive sub-member entry after all, but we assumed the worse when
6155     // we started viz: IncompleteCount!=0.
6156     return;
6157   }
6158   assert(E.Str.empty() && "Entry already present");
6159   E.Str = Str.str();
6160   E.State = IsRecursive? Recursive : NonRecursive;
6161 }
6162 
6163 /// Return a cached TypeString encoding for the ID. If there isn't one, or we
6164 /// are recursively expanding a type (IncompleteCount != 0) and the cached
6165 /// encoding is Recursive, return an empty StringRef.
6166 StringRef TypeStringCache::lookupStr(const IdentifierInfo *ID) {
6167   if (!ID)
6168     return StringRef();   // We have no key.
6169   auto I = Map.find(ID);
6170   if (I == Map.end())
6171     return StringRef();   // We have no encoding.
6172   Entry &E = I->second;
6173   if (E.State == Recursive && IncompleteCount)
6174     return StringRef();   // We don't use Recursive encodings for member types.
6175 
6176   if (E.State == Incomplete) {
6177     // The incomplete type is being used to break out of recursion.
6178     E.State = IncompleteUsed;
6179     ++IncompleteUsedCount;
6180   }
6181   return E.Str.c_str();
6182 }
6183 
6184 /// The XCore ABI includes a type information section that communicates symbol
6185 /// type information to the linker. The linker uses this information to verify
6186 /// safety/correctness of things such as array bound and pointers et al.
6187 /// The ABI only requires C (and XC) language modules to emit TypeStrings.
6188 /// This type information (TypeString) is emitted into meta data for all global
6189 /// symbols: definitions, declarations, functions & variables.
6190 ///
6191 /// The TypeString carries type, qualifier, name, size & value details.
6192 /// Please see 'Tools Development Guide' section 2.16.2 for format details:
6193 /// <https://www.xmos.com/download/public/Tools-Development-Guide%28X9114A%29.pdf>
6194 /// The output is tested by test/CodeGen/xcore-stringtype.c.
6195 ///
6196 static bool getTypeString(SmallStringEnc &Enc, const Decl *D,
6197                           CodeGen::CodeGenModule &CGM, TypeStringCache &TSC);
6198 
6199 /// XCore uses emitTargetMD to emit TypeString metadata for global symbols.
6200 void XCoreTargetCodeGenInfo::emitTargetMD(const Decl *D, llvm::GlobalValue *GV,
6201                                           CodeGen::CodeGenModule &CGM) const {
6202   SmallStringEnc Enc;
6203   if (getTypeString(Enc, D, CGM, TSC)) {
6204     llvm::LLVMContext &Ctx = CGM.getModule().getContext();
6205     llvm::SmallVector<llvm::Value *, 2> MDVals;
6206     MDVals.push_back(GV);
6207     MDVals.push_back(llvm::MDString::get(Ctx, Enc.str()));
6208     llvm::NamedMDNode *MD =
6209       CGM.getModule().getOrInsertNamedMetadata("xcore.typestrings");
6210     MD->addOperand(llvm::MDNode::get(Ctx, MDVals));
6211   }
6212 }
6213 
6214 static bool appendType(SmallStringEnc &Enc, QualType QType,
6215                        const CodeGen::CodeGenModule &CGM,
6216                        TypeStringCache &TSC);
6217 
6218 /// Helper function for appendRecordType().
6219 /// Builds a SmallVector containing the encoded field types in declaration order.
6220 static bool extractFieldType(SmallVectorImpl<FieldEncoding> &FE,
6221                              const RecordDecl *RD,
6222                              const CodeGen::CodeGenModule &CGM,
6223                              TypeStringCache &TSC) {
6224   for (RecordDecl::field_iterator I = RD->field_begin(), E = RD->field_end();
6225        I != E; ++I) {
6226     SmallStringEnc Enc;
6227     Enc += "m(";
6228     Enc += I->getName();
6229     Enc += "){";
6230     if (I->isBitField()) {
6231       Enc += "b(";
6232       llvm::raw_svector_ostream OS(Enc);
6233       OS.resync();
6234       OS << I->getBitWidthValue(CGM.getContext());
6235       OS.flush();
6236       Enc += ':';
6237     }
6238     if (!appendType(Enc, I->getType(), CGM, TSC))
6239       return false;
6240     if (I->isBitField())
6241       Enc += ')';
6242     Enc += '}';
6243     FE.push_back(FieldEncoding(!I->getName().empty(), Enc));
6244   }
6245   return true;
6246 }
6247 
6248 /// Appends structure and union types to Enc and adds encoding to cache.
6249 /// Recursively calls appendType (via extractFieldType) for each field.
6250 /// Union types have their fields ordered according to the ABI.
6251 static bool appendRecordType(SmallStringEnc &Enc, const RecordType *RT,
6252                              const CodeGen::CodeGenModule &CGM,
6253                              TypeStringCache &TSC, const IdentifierInfo *ID) {
6254   // Append the cached TypeString if we have one.
6255   StringRef TypeString = TSC.lookupStr(ID);
6256   if (!TypeString.empty()) {
6257     Enc += TypeString;
6258     return true;
6259   }
6260 
6261   // Start to emit an incomplete TypeString.
6262   size_t Start = Enc.size();
6263   Enc += (RT->isUnionType()? 'u' : 's');
6264   Enc += '(';
6265   if (ID)
6266     Enc += ID->getName();
6267   Enc += "){";
6268 
6269   // We collect all encoded fields and order as necessary.
6270   bool IsRecursive = false;
6271   const RecordDecl *RD = RT->getDecl()->getDefinition();
6272   if (RD && !RD->field_empty()) {
6273     // An incomplete TypeString stub is placed in the cache for this RecordType
6274     // so that recursive calls to this RecordType will use it whilst building a
6275     // complete TypeString for this RecordType.
6276     SmallVector<FieldEncoding, 16> FE;
6277     std::string StubEnc(Enc.substr(Start).str());
6278     StubEnc += '}';  // StubEnc now holds a valid incomplete TypeString.
6279     TSC.addIncomplete(ID, std::move(StubEnc));
6280     if (!extractFieldType(FE, RD, CGM, TSC)) {
6281       (void) TSC.removeIncomplete(ID);
6282       return false;
6283     }
6284     IsRecursive = TSC.removeIncomplete(ID);
6285     // The ABI requires unions to be sorted but not structures.
6286     // See FieldEncoding::operator< for sort algorithm.
6287     if (RT->isUnionType())
6288       std::sort(FE.begin(), FE.end());
6289     // We can now complete the TypeString.
6290     unsigned E = FE.size();
6291     for (unsigned I = 0; I != E; ++I) {
6292       if (I)
6293         Enc += ',';
6294       Enc += FE[I].str();
6295     }
6296   }
6297   Enc += '}';
6298   TSC.addIfComplete(ID, Enc.substr(Start), IsRecursive);
6299   return true;
6300 }
6301 
6302 /// Appends enum types to Enc and adds the encoding to the cache.
6303 static bool appendEnumType(SmallStringEnc &Enc, const EnumType *ET,
6304                            TypeStringCache &TSC,
6305                            const IdentifierInfo *ID) {
6306   // Append the cached TypeString if we have one.
6307   StringRef TypeString = TSC.lookupStr(ID);
6308   if (!TypeString.empty()) {
6309     Enc += TypeString;
6310     return true;
6311   }
6312 
6313   size_t Start = Enc.size();
6314   Enc += "e(";
6315   if (ID)
6316     Enc += ID->getName();
6317   Enc += "){";
6318 
6319   // We collect all encoded enumerations and order them alphanumerically.
6320   if (const EnumDecl *ED = ET->getDecl()->getDefinition()) {
6321     SmallVector<FieldEncoding, 16> FE;
6322     for (auto I = ED->enumerator_begin(), E = ED->enumerator_end(); I != E;
6323          ++I) {
6324       SmallStringEnc EnumEnc;
6325       EnumEnc += "m(";
6326       EnumEnc += I->getName();
6327       EnumEnc += "){";
6328       I->getInitVal().toString(EnumEnc);
6329       EnumEnc += '}';
6330       FE.push_back(FieldEncoding(!I->getName().empty(), EnumEnc));
6331     }
6332     std::sort(FE.begin(), FE.end());
6333     unsigned E = FE.size();
6334     for (unsigned I = 0; I != E; ++I) {
6335       if (I)
6336         Enc += ',';
6337       Enc += FE[I].str();
6338     }
6339   }
6340   Enc += '}';
6341   TSC.addIfComplete(ID, Enc.substr(Start), false);
6342   return true;
6343 }
6344 
6345 /// Appends type's qualifier to Enc.
6346 /// This is done prior to appending the type's encoding.
6347 static void appendQualifier(SmallStringEnc &Enc, QualType QT) {
6348   // Qualifiers are emitted in alphabetical order.
6349   static const char *Table[] = {"","c:","r:","cr:","v:","cv:","rv:","crv:"};
6350   int Lookup = 0;
6351   if (QT.isConstQualified())
6352     Lookup += 1<<0;
6353   if (QT.isRestrictQualified())
6354     Lookup += 1<<1;
6355   if (QT.isVolatileQualified())
6356     Lookup += 1<<2;
6357   Enc += Table[Lookup];
6358 }
6359 
6360 /// Appends built-in types to Enc.
6361 static bool appendBuiltinType(SmallStringEnc &Enc, const BuiltinType *BT) {
6362   const char *EncType;
6363   switch (BT->getKind()) {
6364     case BuiltinType::Void:
6365       EncType = "0";
6366       break;
6367     case BuiltinType::Bool:
6368       EncType = "b";
6369       break;
6370     case BuiltinType::Char_U:
6371       EncType = "uc";
6372       break;
6373     case BuiltinType::UChar:
6374       EncType = "uc";
6375       break;
6376     case BuiltinType::SChar:
6377       EncType = "sc";
6378       break;
6379     case BuiltinType::UShort:
6380       EncType = "us";
6381       break;
6382     case BuiltinType::Short:
6383       EncType = "ss";
6384       break;
6385     case BuiltinType::UInt:
6386       EncType = "ui";
6387       break;
6388     case BuiltinType::Int:
6389       EncType = "si";
6390       break;
6391     case BuiltinType::ULong:
6392       EncType = "ul";
6393       break;
6394     case BuiltinType::Long:
6395       EncType = "sl";
6396       break;
6397     case BuiltinType::ULongLong:
6398       EncType = "ull";
6399       break;
6400     case BuiltinType::LongLong:
6401       EncType = "sll";
6402       break;
6403     case BuiltinType::Float:
6404       EncType = "ft";
6405       break;
6406     case BuiltinType::Double:
6407       EncType = "d";
6408       break;
6409     case BuiltinType::LongDouble:
6410       EncType = "ld";
6411       break;
6412     default:
6413       return false;
6414   }
6415   Enc += EncType;
6416   return true;
6417 }
6418 
6419 /// Appends a pointer encoding to Enc before calling appendType for the pointee.
6420 static bool appendPointerType(SmallStringEnc &Enc, const PointerType *PT,
6421                               const CodeGen::CodeGenModule &CGM,
6422                               TypeStringCache &TSC) {
6423   Enc += "p(";
6424   if (!appendType(Enc, PT->getPointeeType(), CGM, TSC))
6425     return false;
6426   Enc += ')';
6427   return true;
6428 }
6429 
6430 /// Appends array encoding to Enc before calling appendType for the element.
6431 static bool appendArrayType(SmallStringEnc &Enc, QualType QT,
6432                             const ArrayType *AT,
6433                             const CodeGen::CodeGenModule &CGM,
6434                             TypeStringCache &TSC, StringRef NoSizeEnc) {
6435   if (AT->getSizeModifier() != ArrayType::Normal)
6436     return false;
6437   Enc += "a(";
6438   if (const ConstantArrayType *CAT = dyn_cast<ConstantArrayType>(AT))
6439     CAT->getSize().toStringUnsigned(Enc);
6440   else
6441     Enc += NoSizeEnc; // Global arrays use "*", otherwise it is "".
6442   Enc += ':';
6443   // The Qualifiers should be attached to the type rather than the array.
6444   appendQualifier(Enc, QT);
6445   if (!appendType(Enc, AT->getElementType(), CGM, TSC))
6446     return false;
6447   Enc += ')';
6448   return true;
6449 }
6450 
6451 /// Appends a function encoding to Enc, calling appendType for the return type
6452 /// and the arguments.
6453 static bool appendFunctionType(SmallStringEnc &Enc, const FunctionType *FT,
6454                              const CodeGen::CodeGenModule &CGM,
6455                              TypeStringCache &TSC) {
6456   Enc += "f{";
6457   if (!appendType(Enc, FT->getReturnType(), CGM, TSC))
6458     return false;
6459   Enc += "}(";
6460   if (const FunctionProtoType *FPT = FT->getAs<FunctionProtoType>()) {
6461     // N.B. we are only interested in the adjusted param types.
6462     auto I = FPT->param_type_begin();
6463     auto E = FPT->param_type_end();
6464     if (I != E) {
6465       do {
6466         if (!appendType(Enc, *I, CGM, TSC))
6467           return false;
6468         ++I;
6469         if (I != E)
6470           Enc += ',';
6471       } while (I != E);
6472       if (FPT->isVariadic())
6473         Enc += ",va";
6474     } else {
6475       if (FPT->isVariadic())
6476         Enc += "va";
6477       else
6478         Enc += '0';
6479     }
6480   }
6481   Enc += ')';
6482   return true;
6483 }
6484 
6485 /// Handles the type's qualifier before dispatching a call to handle specific
6486 /// type encodings.
6487 static bool appendType(SmallStringEnc &Enc, QualType QType,
6488                        const CodeGen::CodeGenModule &CGM,
6489                        TypeStringCache &TSC) {
6490 
6491   QualType QT = QType.getCanonicalType();
6492 
6493   if (const ArrayType *AT = QT->getAsArrayTypeUnsafe())
6494     // The Qualifiers should be attached to the type rather than the array.
6495     // Thus we don't call appendQualifier() here.
6496     return appendArrayType(Enc, QT, AT, CGM, TSC, "");
6497 
6498   appendQualifier(Enc, QT);
6499 
6500   if (const BuiltinType *BT = QT->getAs<BuiltinType>())
6501     return appendBuiltinType(Enc, BT);
6502 
6503   if (const PointerType *PT = QT->getAs<PointerType>())
6504     return appendPointerType(Enc, PT, CGM, TSC);
6505 
6506   if (const EnumType *ET = QT->getAs<EnumType>())
6507     return appendEnumType(Enc, ET, TSC, QT.getBaseTypeIdentifier());
6508 
6509   if (const RecordType *RT = QT->getAsStructureType())
6510     return appendRecordType(Enc, RT, CGM, TSC, QT.getBaseTypeIdentifier());
6511 
6512   if (const RecordType *RT = QT->getAsUnionType())
6513     return appendRecordType(Enc, RT, CGM, TSC, QT.getBaseTypeIdentifier());
6514 
6515   if (const FunctionType *FT = QT->getAs<FunctionType>())
6516     return appendFunctionType(Enc, FT, CGM, TSC);
6517 
6518   return false;
6519 }
6520 
6521 static bool getTypeString(SmallStringEnc &Enc, const Decl *D,
6522                           CodeGen::CodeGenModule &CGM, TypeStringCache &TSC) {
6523   if (!D)
6524     return false;
6525 
6526   if (const FunctionDecl *FD = dyn_cast<FunctionDecl>(D)) {
6527     if (FD->getLanguageLinkage() != CLanguageLinkage)
6528       return false;
6529     return appendType(Enc, FD->getType(), CGM, TSC);
6530   }
6531 
6532   if (const VarDecl *VD = dyn_cast<VarDecl>(D)) {
6533     if (VD->getLanguageLinkage() != CLanguageLinkage)
6534       return false;
6535     QualType QT = VD->getType().getCanonicalType();
6536     if (const ArrayType *AT = QT->getAsArrayTypeUnsafe()) {
6537       // Global ArrayTypes are given a size of '*' if the size is unknown.
6538       // The Qualifiers should be attached to the type rather than the array.
6539       // Thus we don't call appendQualifier() here.
6540       return appendArrayType(Enc, QT, AT, CGM, TSC, "*");
6541     }
6542     return appendType(Enc, QT, CGM, TSC);
6543   }
6544   return false;
6545 }
6546 
6547 
6548 //===----------------------------------------------------------------------===//
6549 // Driver code
6550 //===----------------------------------------------------------------------===//
6551 
6552 const TargetCodeGenInfo &CodeGenModule::getTargetCodeGenInfo() {
6553   if (TheTargetCodeGenInfo)
6554     return *TheTargetCodeGenInfo;
6555 
6556   const llvm::Triple &Triple = getTarget().getTriple();
6557   switch (Triple.getArch()) {
6558   default:
6559     return *(TheTargetCodeGenInfo = new DefaultTargetCodeGenInfo(Types));
6560 
6561   case llvm::Triple::le32:
6562     return *(TheTargetCodeGenInfo = new PNaClTargetCodeGenInfo(Types));
6563   case llvm::Triple::mips:
6564   case llvm::Triple::mipsel:
6565     return *(TheTargetCodeGenInfo = new MIPSTargetCodeGenInfo(Types, true));
6566 
6567   case llvm::Triple::mips64:
6568   case llvm::Triple::mips64el:
6569     return *(TheTargetCodeGenInfo = new MIPSTargetCodeGenInfo(Types, false));
6570 
6571   case llvm::Triple::aarch64:
6572   case llvm::Triple::aarch64_be:
6573   case llvm::Triple::arm64:
6574   case llvm::Triple::arm64_be: {
6575     AArch64ABIInfo::ABIKind Kind = AArch64ABIInfo::AAPCS;
6576     if (getTarget().getABI() == "darwinpcs")
6577       Kind = AArch64ABIInfo::DarwinPCS;
6578 
6579     return *(TheTargetCodeGenInfo = new AArch64TargetCodeGenInfo(Types, Kind));
6580   }
6581 
6582   case llvm::Triple::arm:
6583   case llvm::Triple::armeb:
6584   case llvm::Triple::thumb:
6585   case llvm::Triple::thumbeb:
6586     {
6587       ARMABIInfo::ABIKind Kind = ARMABIInfo::AAPCS;
6588       if (getTarget().getABI() == "apcs-gnu")
6589         Kind = ARMABIInfo::APCS;
6590       else if (CodeGenOpts.FloatABI == "hard" ||
6591                (CodeGenOpts.FloatABI != "soft" &&
6592                 Triple.getEnvironment() == llvm::Triple::GNUEABIHF))
6593         Kind = ARMABIInfo::AAPCS_VFP;
6594 
6595       switch (Triple.getOS()) {
6596         case llvm::Triple::NaCl:
6597           return *(TheTargetCodeGenInfo =
6598                    new NaClARMTargetCodeGenInfo(Types, Kind));
6599         default:
6600           return *(TheTargetCodeGenInfo =
6601                    new ARMTargetCodeGenInfo(Types, Kind));
6602       }
6603     }
6604 
6605   case llvm::Triple::ppc:
6606     return *(TheTargetCodeGenInfo = new PPC32TargetCodeGenInfo(Types));
6607   case llvm::Triple::ppc64:
6608     if (Triple.isOSBinFormatELF())
6609       return *(TheTargetCodeGenInfo = new PPC64_SVR4_TargetCodeGenInfo(Types));
6610     else
6611       return *(TheTargetCodeGenInfo = new PPC64TargetCodeGenInfo(Types));
6612   case llvm::Triple::ppc64le:
6613     assert(Triple.isOSBinFormatELF() && "PPC64 LE non-ELF not supported!");
6614     return *(TheTargetCodeGenInfo = new PPC64_SVR4_TargetCodeGenInfo(Types));
6615 
6616   case llvm::Triple::nvptx:
6617   case llvm::Triple::nvptx64:
6618     return *(TheTargetCodeGenInfo = new NVPTXTargetCodeGenInfo(Types));
6619 
6620   case llvm::Triple::msp430:
6621     return *(TheTargetCodeGenInfo = new MSP430TargetCodeGenInfo(Types));
6622 
6623   case llvm::Triple::systemz:
6624     return *(TheTargetCodeGenInfo = new SystemZTargetCodeGenInfo(Types));
6625 
6626   case llvm::Triple::tce:
6627     return *(TheTargetCodeGenInfo = new TCETargetCodeGenInfo(Types));
6628 
6629   case llvm::Triple::x86: {
6630     bool IsDarwinVectorABI = Triple.isOSDarwin();
6631     bool IsSmallStructInRegABI =
6632         X86_32TargetCodeGenInfo::isStructReturnInRegABI(Triple, CodeGenOpts);
6633     bool IsWin32FloatStructABI = Triple.isWindowsMSVCEnvironment();
6634 
6635     if (Triple.getOS() == llvm::Triple::Win32) {
6636       return *(TheTargetCodeGenInfo =
6637                new WinX86_32TargetCodeGenInfo(Types,
6638                                               IsDarwinVectorABI, IsSmallStructInRegABI,
6639                                               IsWin32FloatStructABI,
6640                                               CodeGenOpts.NumRegisterParameters));
6641     } else {
6642       return *(TheTargetCodeGenInfo =
6643                new X86_32TargetCodeGenInfo(Types,
6644                                            IsDarwinVectorABI, IsSmallStructInRegABI,
6645                                            IsWin32FloatStructABI,
6646                                            CodeGenOpts.NumRegisterParameters));
6647     }
6648   }
6649 
6650   case llvm::Triple::x86_64: {
6651     bool HasAVX = getTarget().getABI() == "avx";
6652 
6653     switch (Triple.getOS()) {
6654     case llvm::Triple::Win32:
6655       return *(TheTargetCodeGenInfo = new WinX86_64TargetCodeGenInfo(Types));
6656     case llvm::Triple::NaCl:
6657       return *(TheTargetCodeGenInfo = new NaClX86_64TargetCodeGenInfo(Types,
6658                                                                       HasAVX));
6659     default:
6660       return *(TheTargetCodeGenInfo = new X86_64TargetCodeGenInfo(Types,
6661                                                                   HasAVX));
6662     }
6663   }
6664   case llvm::Triple::hexagon:
6665     return *(TheTargetCodeGenInfo = new HexagonTargetCodeGenInfo(Types));
6666   case llvm::Triple::sparcv9:
6667     return *(TheTargetCodeGenInfo = new SparcV9TargetCodeGenInfo(Types));
6668   case llvm::Triple::xcore:
6669     return *(TheTargetCodeGenInfo = new XCoreTargetCodeGenInfo(Types));
6670   }
6671 }
6672