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/Frontend/CodeGenOptions.h"
21 #include "llvm/ADT/Triple.h"
22 #include "llvm/IR/DataLayout.h"
23 #include "llvm/IR/Type.h"
24 #include "llvm/Support/raw_ostream.h"
25 using namespace clang;
26 using namespace CodeGen;
27 
28 static void AssignToArrayRange(CodeGen::CGBuilderTy &Builder,
29                                llvm::Value *Array,
30                                llvm::Value *Value,
31                                unsigned FirstIndex,
32                                unsigned LastIndex) {
33   // Alternatively, we could emit this as a loop in the source.
34   for (unsigned I = FirstIndex; I <= LastIndex; ++I) {
35     llvm::Value *Cell = Builder.CreateConstInBoundsGEP1_32(Array, I);
36     Builder.CreateStore(Value, Cell);
37   }
38 }
39 
40 static bool isAggregateTypeForABI(QualType T) {
41   return !CodeGenFunction::hasScalarEvaluationKind(T) ||
42          T->isMemberFunctionPointerType();
43 }
44 
45 ABIInfo::~ABIInfo() {}
46 
47 static bool isRecordReturnIndirect(const RecordType *RT,
48                                    CGCXXABI &CXXABI) {
49   const CXXRecordDecl *RD = dyn_cast<CXXRecordDecl>(RT->getDecl());
50   if (!RD)
51     return false;
52   return CXXABI.isReturnTypeIndirect(RD);
53 }
54 
55 
56 static bool isRecordReturnIndirect(QualType T, CGCXXABI &CXXABI) {
57   const RecordType *RT = T->getAs<RecordType>();
58   if (!RT)
59     return false;
60   return isRecordReturnIndirect(RT, CXXABI);
61 }
62 
63 static CGCXXABI::RecordArgABI getRecordArgABI(const RecordType *RT,
64                                               CGCXXABI &CXXABI) {
65   const CXXRecordDecl *RD = dyn_cast<CXXRecordDecl>(RT->getDecl());
66   if (!RD)
67     return CGCXXABI::RAA_Default;
68   return CXXABI.getRecordArgABI(RD);
69 }
70 
71 static CGCXXABI::RecordArgABI getRecordArgABI(QualType T,
72                                               CGCXXABI &CXXABI) {
73   const RecordType *RT = T->getAs<RecordType>();
74   if (!RT)
75     return CGCXXABI::RAA_Default;
76   return getRecordArgABI(RT, CXXABI);
77 }
78 
79 CGCXXABI &ABIInfo::getCXXABI() const {
80   return CGT.getCXXABI();
81 }
82 
83 ASTContext &ABIInfo::getContext() const {
84   return CGT.getContext();
85 }
86 
87 llvm::LLVMContext &ABIInfo::getVMContext() const {
88   return CGT.getLLVMContext();
89 }
90 
91 const llvm::DataLayout &ABIInfo::getDataLayout() const {
92   return CGT.getDataLayout();
93 }
94 
95 const TargetInfo &ABIInfo::getTarget() const {
96   return CGT.getTarget();
97 }
98 
99 void ABIArgInfo::dump() const {
100   raw_ostream &OS = llvm::errs();
101   OS << "(ABIArgInfo Kind=";
102   switch (TheKind) {
103   case Direct:
104     OS << "Direct Type=";
105     if (llvm::Type *Ty = getCoerceToType())
106       Ty->print(OS);
107     else
108       OS << "null";
109     break;
110   case Extend:
111     OS << "Extend";
112     break;
113   case Ignore:
114     OS << "Ignore";
115     break;
116   case Indirect:
117     OS << "Indirect Align=" << getIndirectAlign()
118        << " ByVal=" << getIndirectByVal()
119        << " Realign=" << getIndirectRealign();
120     break;
121   case Expand:
122     OS << "Expand";
123     break;
124   }
125   OS << ")\n";
126 }
127 
128 TargetCodeGenInfo::~TargetCodeGenInfo() { delete Info; }
129 
130 // If someone can figure out a general rule for this, that would be great.
131 // It's probably just doomed to be platform-dependent, though.
132 unsigned TargetCodeGenInfo::getSizeOfUnwindException() const {
133   // Verified for:
134   //   x86-64     FreeBSD, Linux, Darwin
135   //   x86-32     FreeBSD, Linux, Darwin
136   //   PowerPC    Linux, Darwin
137   //   ARM        Darwin (*not* EABI)
138   //   AArch64    Linux
139   return 32;
140 }
141 
142 bool TargetCodeGenInfo::isNoProtoCallVariadic(const CallArgList &args,
143                                      const FunctionNoProtoType *fnType) const {
144   // The following conventions are known to require this to be false:
145   //   x86_stdcall
146   //   MIPS
147   // For everything else, we just prefer false unless we opt out.
148   return false;
149 }
150 
151 void
152 TargetCodeGenInfo::getDependentLibraryOption(llvm::StringRef Lib,
153                                              llvm::SmallString<24> &Opt) const {
154   // This assumes the user is passing a library name like "rt" instead of a
155   // filename like "librt.a/so", and that they don't care whether it's static or
156   // dynamic.
157   Opt = "-l";
158   Opt += Lib;
159 }
160 
161 static bool isEmptyRecord(ASTContext &Context, QualType T, bool AllowArrays);
162 
163 /// isEmptyField - Return true iff a the field is "empty", that is it
164 /// is an unnamed bit-field or an (array of) empty record(s).
165 static bool isEmptyField(ASTContext &Context, const FieldDecl *FD,
166                          bool AllowArrays) {
167   if (FD->isUnnamedBitfield())
168     return true;
169 
170   QualType FT = FD->getType();
171 
172   // Constant arrays of empty records count as empty, strip them off.
173   // Constant arrays of zero length always count as empty.
174   if (AllowArrays)
175     while (const ConstantArrayType *AT = Context.getAsConstantArrayType(FT)) {
176       if (AT->getSize() == 0)
177         return true;
178       FT = AT->getElementType();
179     }
180 
181   const RecordType *RT = FT->getAs<RecordType>();
182   if (!RT)
183     return false;
184 
185   // C++ record fields are never empty, at least in the Itanium ABI.
186   //
187   // FIXME: We should use a predicate for whether this behavior is true in the
188   // current ABI.
189   if (isa<CXXRecordDecl>(RT->getDecl()))
190     return false;
191 
192   return isEmptyRecord(Context, FT, AllowArrays);
193 }
194 
195 /// isEmptyRecord - Return true iff a structure contains only empty
196 /// fields. Note that a structure with a flexible array member is not
197 /// considered empty.
198 static bool isEmptyRecord(ASTContext &Context, QualType T, bool AllowArrays) {
199   const RecordType *RT = T->getAs<RecordType>();
200   if (!RT)
201     return 0;
202   const RecordDecl *RD = RT->getDecl();
203   if (RD->hasFlexibleArrayMember())
204     return false;
205 
206   // If this is a C++ record, check the bases first.
207   if (const CXXRecordDecl *CXXRD = dyn_cast<CXXRecordDecl>(RD))
208     for (CXXRecordDecl::base_class_const_iterator i = CXXRD->bases_begin(),
209            e = CXXRD->bases_end(); i != e; ++i)
210       if (!isEmptyRecord(Context, i->getType(), true))
211         return false;
212 
213   for (RecordDecl::field_iterator i = RD->field_begin(), e = RD->field_end();
214          i != e; ++i)
215     if (!isEmptyField(Context, *i, AllowArrays))
216       return false;
217   return true;
218 }
219 
220 /// isSingleElementStruct - Determine if a structure is a "single
221 /// element struct", i.e. it has exactly one non-empty field or
222 /// exactly one field which is itself a single element
223 /// struct. Structures with flexible array members are never
224 /// considered single element structs.
225 ///
226 /// \return The field declaration for the single non-empty field, if
227 /// it exists.
228 static const Type *isSingleElementStruct(QualType T, ASTContext &Context) {
229   const RecordType *RT = T->getAsStructureType();
230   if (!RT)
231     return 0;
232 
233   const RecordDecl *RD = RT->getDecl();
234   if (RD->hasFlexibleArrayMember())
235     return 0;
236 
237   const Type *Found = 0;
238 
239   // If this is a C++ record, check the bases first.
240   if (const CXXRecordDecl *CXXRD = dyn_cast<CXXRecordDecl>(RD)) {
241     for (CXXRecordDecl::base_class_const_iterator i = CXXRD->bases_begin(),
242            e = CXXRD->bases_end(); i != e; ++i) {
243       // Ignore empty records.
244       if (isEmptyRecord(Context, i->getType(), true))
245         continue;
246 
247       // If we already found an element then this isn't a single-element struct.
248       if (Found)
249         return 0;
250 
251       // If this is non-empty and not a single element struct, the composite
252       // cannot be a single element struct.
253       Found = isSingleElementStruct(i->getType(), Context);
254       if (!Found)
255         return 0;
256     }
257   }
258 
259   // Check for single element.
260   for (RecordDecl::field_iterator i = RD->field_begin(), e = RD->field_end();
261          i != e; ++i) {
262     const FieldDecl *FD = *i;
263     QualType FT = FD->getType();
264 
265     // Ignore empty fields.
266     if (isEmptyField(Context, FD, true))
267       continue;
268 
269     // If we already found an element then this isn't a single-element
270     // struct.
271     if (Found)
272       return 0;
273 
274     // Treat single element arrays as the element.
275     while (const ConstantArrayType *AT = Context.getAsConstantArrayType(FT)) {
276       if (AT->getSize().getZExtValue() != 1)
277         break;
278       FT = AT->getElementType();
279     }
280 
281     if (!isAggregateTypeForABI(FT)) {
282       Found = FT.getTypePtr();
283     } else {
284       Found = isSingleElementStruct(FT, Context);
285       if (!Found)
286         return 0;
287     }
288   }
289 
290   // We don't consider a struct a single-element struct if it has
291   // padding beyond the element type.
292   if (Found && Context.getTypeSize(Found) != Context.getTypeSize(T))
293     return 0;
294 
295   return Found;
296 }
297 
298 static bool is32Or64BitBasicType(QualType Ty, ASTContext &Context) {
299   // Treat complex types as the element type.
300   if (const ComplexType *CTy = Ty->getAs<ComplexType>())
301     Ty = CTy->getElementType();
302 
303   // Check for a type which we know has a simple scalar argument-passing
304   // convention without any padding.  (We're specifically looking for 32
305   // and 64-bit integer and integer-equivalents, float, and double.)
306   if (!Ty->getAs<BuiltinType>() && !Ty->hasPointerRepresentation() &&
307       !Ty->isEnumeralType() && !Ty->isBlockPointerType())
308     return false;
309 
310   uint64_t Size = Context.getTypeSize(Ty);
311   return Size == 32 || Size == 64;
312 }
313 
314 /// canExpandIndirectArgument - Test whether an argument type which is to be
315 /// passed indirectly (on the stack) would have the equivalent layout if it was
316 /// expanded into separate arguments. If so, we prefer to do the latter to avoid
317 /// inhibiting optimizations.
318 ///
319 // FIXME: This predicate is missing many cases, currently it just follows
320 // llvm-gcc (checks that all fields are 32-bit or 64-bit primitive types). We
321 // should probably make this smarter, or better yet make the LLVM backend
322 // capable of handling it.
323 static bool canExpandIndirectArgument(QualType Ty, ASTContext &Context) {
324   // We can only expand structure types.
325   const RecordType *RT = Ty->getAs<RecordType>();
326   if (!RT)
327     return false;
328 
329   // We can only expand (C) structures.
330   //
331   // FIXME: This needs to be generalized to handle classes as well.
332   const RecordDecl *RD = RT->getDecl();
333   if (!RD->isStruct() || isa<CXXRecordDecl>(RD))
334     return false;
335 
336   uint64_t Size = 0;
337 
338   for (RecordDecl::field_iterator i = RD->field_begin(), e = RD->field_end();
339          i != e; ++i) {
340     const FieldDecl *FD = *i;
341 
342     if (!is32Or64BitBasicType(FD->getType(), Context))
343       return false;
344 
345     // FIXME: Reject bit-fields wholesale; there are two problems, we don't know
346     // how to expand them yet, and the predicate for telling if a bitfield still
347     // counts as "basic" is more complicated than what we were doing previously.
348     if (FD->isBitField())
349       return false;
350 
351     Size += Context.getTypeSize(FD->getType());
352   }
353 
354   // Make sure there are not any holes in the struct.
355   if (Size != Context.getTypeSize(Ty))
356     return false;
357 
358   return true;
359 }
360 
361 namespace {
362 /// DefaultABIInfo - The default implementation for ABI specific
363 /// details. This implementation provides information which results in
364 /// self-consistent and sensible LLVM IR generation, but does not
365 /// conform to any particular ABI.
366 class DefaultABIInfo : public ABIInfo {
367 public:
368   DefaultABIInfo(CodeGen::CodeGenTypes &CGT) : ABIInfo(CGT) {}
369 
370   ABIArgInfo classifyReturnType(QualType RetTy) const;
371   ABIArgInfo classifyArgumentType(QualType RetTy) const;
372 
373   virtual void computeInfo(CGFunctionInfo &FI) const {
374     FI.getReturnInfo() = classifyReturnType(FI.getReturnType());
375     for (CGFunctionInfo::arg_iterator it = FI.arg_begin(), ie = FI.arg_end();
376          it != ie; ++it)
377       it->info = classifyArgumentType(it->type);
378   }
379 
380   virtual llvm::Value *EmitVAArg(llvm::Value *VAListAddr, QualType Ty,
381                                  CodeGenFunction &CGF) const;
382 };
383 
384 class DefaultTargetCodeGenInfo : public TargetCodeGenInfo {
385 public:
386   DefaultTargetCodeGenInfo(CodeGen::CodeGenTypes &CGT)
387     : TargetCodeGenInfo(new DefaultABIInfo(CGT)) {}
388 };
389 
390 llvm::Value *DefaultABIInfo::EmitVAArg(llvm::Value *VAListAddr, QualType Ty,
391                                        CodeGenFunction &CGF) const {
392   return 0;
393 }
394 
395 ABIArgInfo DefaultABIInfo::classifyArgumentType(QualType Ty) const {
396   if (isAggregateTypeForABI(Ty)) {
397     // Records with non trivial destructors/constructors should not be passed
398     // by value.
399     if (isRecordReturnIndirect(Ty, getCXXABI()))
400       return ABIArgInfo::getIndirect(0, /*ByVal=*/false);
401 
402     return ABIArgInfo::getIndirect(0);
403   }
404 
405   // Treat an enum type as its underlying type.
406   if (const EnumType *EnumTy = Ty->getAs<EnumType>())
407     Ty = EnumTy->getDecl()->getIntegerType();
408 
409   return (Ty->isPromotableIntegerType() ?
410           ABIArgInfo::getExtend() : ABIArgInfo::getDirect());
411 }
412 
413 ABIArgInfo DefaultABIInfo::classifyReturnType(QualType RetTy) const {
414   if (RetTy->isVoidType())
415     return ABIArgInfo::getIgnore();
416 
417   if (isAggregateTypeForABI(RetTy))
418     return ABIArgInfo::getIndirect(0);
419 
420   // Treat an enum type as its underlying type.
421   if (const EnumType *EnumTy = RetTy->getAs<EnumType>())
422     RetTy = EnumTy->getDecl()->getIntegerType();
423 
424   return (RetTy->isPromotableIntegerType() ?
425           ABIArgInfo::getExtend() : ABIArgInfo::getDirect());
426 }
427 
428 //===----------------------------------------------------------------------===//
429 // le32/PNaCl bitcode ABI Implementation
430 //
431 // This is a simplified version of the x86_32 ABI.  Arguments and return values
432 // are always passed on the stack.
433 //===----------------------------------------------------------------------===//
434 
435 class PNaClABIInfo : public ABIInfo {
436  public:
437   PNaClABIInfo(CodeGen::CodeGenTypes &CGT) : ABIInfo(CGT) {}
438 
439   ABIArgInfo classifyReturnType(QualType RetTy) const;
440   ABIArgInfo classifyArgumentType(QualType RetTy) const;
441 
442   virtual void computeInfo(CGFunctionInfo &FI) const;
443   virtual llvm::Value *EmitVAArg(llvm::Value *VAListAddr, QualType Ty,
444                                  CodeGenFunction &CGF) const;
445 };
446 
447 class PNaClTargetCodeGenInfo : public TargetCodeGenInfo {
448  public:
449   PNaClTargetCodeGenInfo(CodeGen::CodeGenTypes &CGT)
450     : TargetCodeGenInfo(new PNaClABIInfo(CGT)) {}
451 };
452 
453 void PNaClABIInfo::computeInfo(CGFunctionInfo &FI) const {
454     FI.getReturnInfo() = classifyReturnType(FI.getReturnType());
455 
456     for (CGFunctionInfo::arg_iterator it = FI.arg_begin(), ie = FI.arg_end();
457          it != ie; ++it)
458       it->info = classifyArgumentType(it->type);
459   }
460 
461 llvm::Value *PNaClABIInfo::EmitVAArg(llvm::Value *VAListAddr, QualType Ty,
462                                        CodeGenFunction &CGF) const {
463   return 0;
464 }
465 
466 /// \brief Classify argument of given type \p Ty.
467 ABIArgInfo PNaClABIInfo::classifyArgumentType(QualType Ty) const {
468   if (isAggregateTypeForABI(Ty)) {
469     if (CGCXXABI::RecordArgABI RAA = getRecordArgABI(Ty, getCXXABI()))
470       return ABIArgInfo::getIndirect(0, RAA == CGCXXABI::RAA_DirectInMemory);
471     return ABIArgInfo::getIndirect(0);
472   } else if (const EnumType *EnumTy = Ty->getAs<EnumType>()) {
473     // Treat an enum type as its underlying type.
474     Ty = EnumTy->getDecl()->getIntegerType();
475   } else if (Ty->isFloatingType()) {
476     // Floating-point types don't go inreg.
477     return ABIArgInfo::getDirect();
478   }
479 
480   return (Ty->isPromotableIntegerType() ?
481           ABIArgInfo::getExtend() : ABIArgInfo::getDirect());
482 }
483 
484 ABIArgInfo PNaClABIInfo::classifyReturnType(QualType RetTy) const {
485   if (RetTy->isVoidType())
486     return ABIArgInfo::getIgnore();
487 
488   // In the PNaCl ABI we always return records/structures on the stack.
489   if (isAggregateTypeForABI(RetTy))
490     return ABIArgInfo::getIndirect(0);
491 
492   // Treat an enum type as its underlying type.
493   if (const EnumType *EnumTy = RetTy->getAs<EnumType>())
494     RetTy = EnumTy->getDecl()->getIntegerType();
495 
496   return (RetTy->isPromotableIntegerType() ?
497           ABIArgInfo::getExtend() : ABIArgInfo::getDirect());
498 }
499 
500 /// IsX86_MMXType - Return true if this is an MMX type.
501 bool IsX86_MMXType(llvm::Type *IRType) {
502   // Return true if the type is an MMX type <2 x i32>, <4 x i16>, or <8 x i8>.
503   return IRType->isVectorTy() && IRType->getPrimitiveSizeInBits() == 64 &&
504     cast<llvm::VectorType>(IRType)->getElementType()->isIntegerTy() &&
505     IRType->getScalarSizeInBits() != 64;
506 }
507 
508 static llvm::Type* X86AdjustInlineAsmType(CodeGen::CodeGenFunction &CGF,
509                                           StringRef Constraint,
510                                           llvm::Type* Ty) {
511   if ((Constraint == "y" || Constraint == "&y") && Ty->isVectorTy()) {
512     if (cast<llvm::VectorType>(Ty)->getBitWidth() != 64) {
513       // Invalid MMX constraint
514       return 0;
515     }
516 
517     return llvm::Type::getX86_MMXTy(CGF.getLLVMContext());
518   }
519 
520   // No operation needed
521   return Ty;
522 }
523 
524 //===----------------------------------------------------------------------===//
525 // X86-32 ABI Implementation
526 //===----------------------------------------------------------------------===//
527 
528 /// X86_32ABIInfo - The X86-32 ABI information.
529 class X86_32ABIInfo : public ABIInfo {
530   enum Class {
531     Integer,
532     Float
533   };
534 
535   static const unsigned MinABIStackAlignInBytes = 4;
536 
537   bool IsDarwinVectorABI;
538   bool IsSmallStructInRegABI;
539   bool IsWin32StructABI;
540   unsigned DefaultNumRegisterParameters;
541 
542   static bool isRegisterSize(unsigned Size) {
543     return (Size == 8 || Size == 16 || Size == 32 || Size == 64);
544   }
545 
546   static bool shouldReturnTypeInRegister(QualType Ty, ASTContext &Context,
547                                           unsigned callingConvention);
548 
549   /// getIndirectResult - Give a source type \arg Ty, return a suitable result
550   /// such that the argument will be passed in memory.
551   ABIArgInfo getIndirectResult(QualType Ty, bool ByVal,
552                                unsigned &FreeRegs) const;
553 
554   /// \brief Return the alignment to use for the given type on the stack.
555   unsigned getTypeStackAlignInBytes(QualType Ty, unsigned Align) const;
556 
557   Class classify(QualType Ty) const;
558   ABIArgInfo classifyReturnType(QualType RetTy,
559                                 unsigned callingConvention) const;
560   ABIArgInfo classifyArgumentType(QualType RetTy, unsigned &FreeRegs,
561                                   bool IsFastCall) const;
562   bool shouldUseInReg(QualType Ty, unsigned &FreeRegs,
563                       bool IsFastCall, bool &NeedsPadding) const;
564 
565 public:
566 
567   virtual void computeInfo(CGFunctionInfo &FI) const;
568   virtual llvm::Value *EmitVAArg(llvm::Value *VAListAddr, QualType Ty,
569                                  CodeGenFunction &CGF) const;
570 
571   X86_32ABIInfo(CodeGen::CodeGenTypes &CGT, bool d, bool p, bool w,
572                 unsigned r)
573     : ABIInfo(CGT), IsDarwinVectorABI(d), IsSmallStructInRegABI(p),
574       IsWin32StructABI(w), DefaultNumRegisterParameters(r) {}
575 };
576 
577 class X86_32TargetCodeGenInfo : public TargetCodeGenInfo {
578 public:
579   X86_32TargetCodeGenInfo(CodeGen::CodeGenTypes &CGT,
580       bool d, bool p, bool w, unsigned r)
581     :TargetCodeGenInfo(new X86_32ABIInfo(CGT, d, p, w, r)) {}
582 
583   static bool isStructReturnInRegABI(
584       const llvm::Triple &Triple, const CodeGenOptions &Opts);
585 
586   void SetTargetAttributes(const Decl *D, llvm::GlobalValue *GV,
587                            CodeGen::CodeGenModule &CGM) const;
588 
589   int getDwarfEHStackPointer(CodeGen::CodeGenModule &CGM) const {
590     // Darwin uses different dwarf register numbers for EH.
591     if (CGM.getTarget().getTriple().isOSDarwin()) return 5;
592     return 4;
593   }
594 
595   bool initDwarfEHRegSizeTable(CodeGen::CodeGenFunction &CGF,
596                                llvm::Value *Address) const;
597 
598   llvm::Type* adjustInlineAsmType(CodeGen::CodeGenFunction &CGF,
599                                   StringRef Constraint,
600                                   llvm::Type* Ty) const {
601     return X86AdjustInlineAsmType(CGF, Constraint, Ty);
602   }
603 
604   llvm::Constant *getUBSanFunctionSignature(CodeGen::CodeGenModule &CGM) const {
605     unsigned Sig = (0xeb << 0) |  // jmp rel8
606                    (0x06 << 8) |  //           .+0x08
607                    ('F' << 16) |
608                    ('T' << 24);
609     return llvm::ConstantInt::get(CGM.Int32Ty, Sig);
610   }
611 
612 };
613 
614 }
615 
616 /// shouldReturnTypeInRegister - Determine if the given type should be
617 /// passed in a register (for the Darwin ABI).
618 bool X86_32ABIInfo::shouldReturnTypeInRegister(QualType Ty,
619                                                ASTContext &Context,
620                                                unsigned callingConvention) {
621   uint64_t Size = Context.getTypeSize(Ty);
622 
623   // Type must be register sized.
624   if (!isRegisterSize(Size))
625     return false;
626 
627   if (Ty->isVectorType()) {
628     // 64- and 128- bit vectors inside structures are not returned in
629     // registers.
630     if (Size == 64 || Size == 128)
631       return false;
632 
633     return true;
634   }
635 
636   // If this is a builtin, pointer, enum, complex type, member pointer, or
637   // member function pointer it is ok.
638   if (Ty->getAs<BuiltinType>() || Ty->hasPointerRepresentation() ||
639       Ty->isAnyComplexType() || Ty->isEnumeralType() ||
640       Ty->isBlockPointerType() || Ty->isMemberPointerType())
641     return true;
642 
643   // Arrays are treated like records.
644   if (const ConstantArrayType *AT = Context.getAsConstantArrayType(Ty))
645     return shouldReturnTypeInRegister(AT->getElementType(), Context,
646                                       callingConvention);
647 
648   // Otherwise, it must be a record type.
649   const RecordType *RT = Ty->getAs<RecordType>();
650   if (!RT) return false;
651 
652   // FIXME: Traverse bases here too.
653 
654   // For thiscall conventions, structures will never be returned in
655   // a register.  This is for compatibility with the MSVC ABI
656   if (callingConvention == llvm::CallingConv::X86_ThisCall &&
657       RT->isStructureType()) {
658     return false;
659   }
660 
661   // Structure types are passed in register if all fields would be
662   // passed in a register.
663   for (RecordDecl::field_iterator i = RT->getDecl()->field_begin(),
664          e = RT->getDecl()->field_end(); i != e; ++i) {
665     const FieldDecl *FD = *i;
666 
667     // Empty fields are ignored.
668     if (isEmptyField(Context, FD, true))
669       continue;
670 
671     // Check fields recursively.
672     if (!shouldReturnTypeInRegister(FD->getType(), Context,
673                                     callingConvention))
674       return false;
675   }
676   return true;
677 }
678 
679 ABIArgInfo X86_32ABIInfo::classifyReturnType(QualType RetTy,
680                                             unsigned callingConvention) const {
681   if (RetTy->isVoidType())
682     return ABIArgInfo::getIgnore();
683 
684   if (const VectorType *VT = RetTy->getAs<VectorType>()) {
685     // On Darwin, some vectors are returned in registers.
686     if (IsDarwinVectorABI) {
687       uint64_t Size = getContext().getTypeSize(RetTy);
688 
689       // 128-bit vectors are a special case; they are returned in
690       // registers and we need to make sure to pick a type the LLVM
691       // backend will like.
692       if (Size == 128)
693         return ABIArgInfo::getDirect(llvm::VectorType::get(
694                   llvm::Type::getInt64Ty(getVMContext()), 2));
695 
696       // Always return in register if it fits in a general purpose
697       // register, or if it is 64 bits and has a single element.
698       if ((Size == 8 || Size == 16 || Size == 32) ||
699           (Size == 64 && VT->getNumElements() == 1))
700         return ABIArgInfo::getDirect(llvm::IntegerType::get(getVMContext(),
701                                                             Size));
702 
703       return ABIArgInfo::getIndirect(0);
704     }
705 
706     return ABIArgInfo::getDirect();
707   }
708 
709   if (isAggregateTypeForABI(RetTy)) {
710     if (const RecordType *RT = RetTy->getAs<RecordType>()) {
711       if (isRecordReturnIndirect(RT, getCXXABI()))
712         return ABIArgInfo::getIndirect(0, /*ByVal=*/false);
713 
714       // Structures with flexible arrays are always indirect.
715       if (RT->getDecl()->hasFlexibleArrayMember())
716         return ABIArgInfo::getIndirect(0);
717     }
718 
719     // If specified, structs and unions are always indirect.
720     if (!IsSmallStructInRegABI && !RetTy->isAnyComplexType())
721       return ABIArgInfo::getIndirect(0);
722 
723     // Small structures which are register sized are generally returned
724     // in a register.
725     if (X86_32ABIInfo::shouldReturnTypeInRegister(RetTy, getContext(),
726                                                   callingConvention)) {
727       uint64_t Size = getContext().getTypeSize(RetTy);
728 
729       // As a special-case, if the struct is a "single-element" struct, and
730       // the field is of type "float" or "double", return it in a
731       // floating-point register. (MSVC does not apply this special case.)
732       // We apply a similar transformation for pointer types to improve the
733       // quality of the generated IR.
734       if (const Type *SeltTy = isSingleElementStruct(RetTy, getContext()))
735         if ((!IsWin32StructABI && SeltTy->isRealFloatingType())
736             || SeltTy->hasPointerRepresentation())
737           return ABIArgInfo::getDirect(CGT.ConvertType(QualType(SeltTy, 0)));
738 
739       // FIXME: We should be able to narrow this integer in cases with dead
740       // padding.
741       return ABIArgInfo::getDirect(llvm::IntegerType::get(getVMContext(),Size));
742     }
743 
744     return ABIArgInfo::getIndirect(0);
745   }
746 
747   // Treat an enum type as its underlying type.
748   if (const EnumType *EnumTy = RetTy->getAs<EnumType>())
749     RetTy = EnumTy->getDecl()->getIntegerType();
750 
751   return (RetTy->isPromotableIntegerType() ?
752           ABIArgInfo::getExtend() : ABIArgInfo::getDirect());
753 }
754 
755 static bool isSSEVectorType(ASTContext &Context, QualType Ty) {
756   return Ty->getAs<VectorType>() && Context.getTypeSize(Ty) == 128;
757 }
758 
759 static bool isRecordWithSSEVectorType(ASTContext &Context, QualType Ty) {
760   const RecordType *RT = Ty->getAs<RecordType>();
761   if (!RT)
762     return 0;
763   const RecordDecl *RD = RT->getDecl();
764 
765   // If this is a C++ record, check the bases first.
766   if (const CXXRecordDecl *CXXRD = dyn_cast<CXXRecordDecl>(RD))
767     for (CXXRecordDecl::base_class_const_iterator i = CXXRD->bases_begin(),
768            e = CXXRD->bases_end(); i != e; ++i)
769       if (!isRecordWithSSEVectorType(Context, i->getType()))
770         return false;
771 
772   for (RecordDecl::field_iterator i = RD->field_begin(), e = RD->field_end();
773        i != e; ++i) {
774     QualType FT = i->getType();
775 
776     if (isSSEVectorType(Context, FT))
777       return true;
778 
779     if (isRecordWithSSEVectorType(Context, FT))
780       return true;
781   }
782 
783   return false;
784 }
785 
786 unsigned X86_32ABIInfo::getTypeStackAlignInBytes(QualType Ty,
787                                                  unsigned Align) const {
788   // Otherwise, if the alignment is less than or equal to the minimum ABI
789   // alignment, just use the default; the backend will handle this.
790   if (Align <= MinABIStackAlignInBytes)
791     return 0; // Use default alignment.
792 
793   // On non-Darwin, the stack type alignment is always 4.
794   if (!IsDarwinVectorABI) {
795     // Set explicit alignment, since we may need to realign the top.
796     return MinABIStackAlignInBytes;
797   }
798 
799   // Otherwise, if the type contains an SSE vector type, the alignment is 16.
800   if (Align >= 16 && (isSSEVectorType(getContext(), Ty) ||
801                       isRecordWithSSEVectorType(getContext(), Ty)))
802     return 16;
803 
804   return MinABIStackAlignInBytes;
805 }
806 
807 ABIArgInfo X86_32ABIInfo::getIndirectResult(QualType Ty, bool ByVal,
808                                             unsigned &FreeRegs) const {
809   if (!ByVal) {
810     if (FreeRegs) {
811       --FreeRegs; // Non byval indirects just use one pointer.
812       return ABIArgInfo::getIndirectInReg(0, false);
813     }
814     return ABIArgInfo::getIndirect(0, false);
815   }
816 
817   // Compute the byval alignment.
818   unsigned TypeAlign = getContext().getTypeAlign(Ty) / 8;
819   unsigned StackAlign = getTypeStackAlignInBytes(Ty, TypeAlign);
820   if (StackAlign == 0)
821     return ABIArgInfo::getIndirect(4);
822 
823   // If the stack alignment is less than the type alignment, realign the
824   // argument.
825   if (StackAlign < TypeAlign)
826     return ABIArgInfo::getIndirect(StackAlign, /*ByVal=*/true,
827                                    /*Realign=*/true);
828 
829   return ABIArgInfo::getIndirect(StackAlign);
830 }
831 
832 X86_32ABIInfo::Class X86_32ABIInfo::classify(QualType Ty) const {
833   const Type *T = isSingleElementStruct(Ty, getContext());
834   if (!T)
835     T = Ty.getTypePtr();
836 
837   if (const BuiltinType *BT = T->getAs<BuiltinType>()) {
838     BuiltinType::Kind K = BT->getKind();
839     if (K == BuiltinType::Float || K == BuiltinType::Double)
840       return Float;
841   }
842   return Integer;
843 }
844 
845 bool X86_32ABIInfo::shouldUseInReg(QualType Ty, unsigned &FreeRegs,
846                                    bool IsFastCall, bool &NeedsPadding) const {
847   NeedsPadding = false;
848   Class C = classify(Ty);
849   if (C == Float)
850     return false;
851 
852   unsigned Size = getContext().getTypeSize(Ty);
853   unsigned SizeInRegs = (Size + 31) / 32;
854 
855   if (SizeInRegs == 0)
856     return false;
857 
858   if (SizeInRegs > FreeRegs) {
859     FreeRegs = 0;
860     return false;
861   }
862 
863   FreeRegs -= SizeInRegs;
864 
865   if (IsFastCall) {
866     if (Size > 32)
867       return false;
868 
869     if (Ty->isIntegralOrEnumerationType())
870       return true;
871 
872     if (Ty->isPointerType())
873       return true;
874 
875     if (Ty->isReferenceType())
876       return true;
877 
878     if (FreeRegs)
879       NeedsPadding = true;
880 
881     return false;
882   }
883 
884   return true;
885 }
886 
887 ABIArgInfo X86_32ABIInfo::classifyArgumentType(QualType Ty,
888                                                unsigned &FreeRegs,
889                                                bool IsFastCall) const {
890   // FIXME: Set alignment on indirect arguments.
891   if (isAggregateTypeForABI(Ty)) {
892     if (const RecordType *RT = Ty->getAs<RecordType>()) {
893       if (IsWin32StructABI)
894         return getIndirectResult(Ty, true, FreeRegs);
895 
896       if (CGCXXABI::RecordArgABI RAA = getRecordArgABI(RT, getCXXABI()))
897         return getIndirectResult(Ty, RAA == CGCXXABI::RAA_DirectInMemory, FreeRegs);
898 
899       // Structures with flexible arrays are always indirect.
900       if (RT->getDecl()->hasFlexibleArrayMember())
901         return getIndirectResult(Ty, true, FreeRegs);
902     }
903 
904     // Ignore empty structs/unions.
905     if (isEmptyRecord(getContext(), Ty, true))
906       return ABIArgInfo::getIgnore();
907 
908     llvm::LLVMContext &LLVMContext = getVMContext();
909     llvm::IntegerType *Int32 = llvm::Type::getInt32Ty(LLVMContext);
910     bool NeedsPadding;
911     if (shouldUseInReg(Ty, FreeRegs, IsFastCall, NeedsPadding)) {
912       unsigned SizeInRegs = (getContext().getTypeSize(Ty) + 31) / 32;
913       SmallVector<llvm::Type*, 3> Elements(SizeInRegs, Int32);
914       llvm::Type *Result = llvm::StructType::get(LLVMContext, Elements);
915       return ABIArgInfo::getDirectInReg(Result);
916     }
917     llvm::IntegerType *PaddingType = NeedsPadding ? Int32 : 0;
918 
919     // Expand small (<= 128-bit) record types when we know that the stack layout
920     // of those arguments will match the struct. This is important because the
921     // LLVM backend isn't smart enough to remove byval, which inhibits many
922     // optimizations.
923     if (getContext().getTypeSize(Ty) <= 4*32 &&
924         canExpandIndirectArgument(Ty, getContext()))
925       return ABIArgInfo::getExpandWithPadding(IsFastCall, PaddingType);
926 
927     return getIndirectResult(Ty, true, FreeRegs);
928   }
929 
930   if (const VectorType *VT = Ty->getAs<VectorType>()) {
931     // On Darwin, some vectors are passed in memory, we handle this by passing
932     // it as an i8/i16/i32/i64.
933     if (IsDarwinVectorABI) {
934       uint64_t Size = getContext().getTypeSize(Ty);
935       if ((Size == 8 || Size == 16 || Size == 32) ||
936           (Size == 64 && VT->getNumElements() == 1))
937         return ABIArgInfo::getDirect(llvm::IntegerType::get(getVMContext(),
938                                                             Size));
939     }
940 
941     if (IsX86_MMXType(CGT.ConvertType(Ty)))
942       return ABIArgInfo::getDirect(llvm::IntegerType::get(getVMContext(), 64));
943 
944     return ABIArgInfo::getDirect();
945   }
946 
947 
948   if (const EnumType *EnumTy = Ty->getAs<EnumType>())
949     Ty = EnumTy->getDecl()->getIntegerType();
950 
951   bool NeedsPadding;
952   bool InReg = shouldUseInReg(Ty, FreeRegs, IsFastCall, NeedsPadding);
953 
954   if (Ty->isPromotableIntegerType()) {
955     if (InReg)
956       return ABIArgInfo::getExtendInReg();
957     return ABIArgInfo::getExtend();
958   }
959   if (InReg)
960     return ABIArgInfo::getDirectInReg();
961   return ABIArgInfo::getDirect();
962 }
963 
964 void X86_32ABIInfo::computeInfo(CGFunctionInfo &FI) const {
965   FI.getReturnInfo() = classifyReturnType(FI.getReturnType(),
966                                           FI.getCallingConvention());
967 
968   unsigned CC = FI.getCallingConvention();
969   bool IsFastCall = CC == llvm::CallingConv::X86_FastCall;
970   unsigned FreeRegs;
971   if (IsFastCall)
972     FreeRegs = 2;
973   else if (FI.getHasRegParm())
974     FreeRegs = FI.getRegParm();
975   else
976     FreeRegs = DefaultNumRegisterParameters;
977 
978   // If the return value is indirect, then the hidden argument is consuming one
979   // integer register.
980   if (FI.getReturnInfo().isIndirect() && FreeRegs) {
981     --FreeRegs;
982     ABIArgInfo &Old = FI.getReturnInfo();
983     Old = ABIArgInfo::getIndirectInReg(Old.getIndirectAlign(),
984                                        Old.getIndirectByVal(),
985                                        Old.getIndirectRealign());
986   }
987 
988   for (CGFunctionInfo::arg_iterator it = FI.arg_begin(), ie = FI.arg_end();
989        it != ie; ++it)
990     it->info = classifyArgumentType(it->type, FreeRegs, IsFastCall);
991 }
992 
993 llvm::Value *X86_32ABIInfo::EmitVAArg(llvm::Value *VAListAddr, QualType Ty,
994                                       CodeGenFunction &CGF) const {
995   llvm::Type *BPP = CGF.Int8PtrPtrTy;
996 
997   CGBuilderTy &Builder = CGF.Builder;
998   llvm::Value *VAListAddrAsBPP = Builder.CreateBitCast(VAListAddr, BPP,
999                                                        "ap");
1000   llvm::Value *Addr = Builder.CreateLoad(VAListAddrAsBPP, "ap.cur");
1001 
1002   // Compute if the address needs to be aligned
1003   unsigned Align = CGF.getContext().getTypeAlignInChars(Ty).getQuantity();
1004   Align = getTypeStackAlignInBytes(Ty, Align);
1005   Align = std::max(Align, 4U);
1006   if (Align > 4) {
1007     // addr = (addr + align - 1) & -align;
1008     llvm::Value *Offset =
1009       llvm::ConstantInt::get(CGF.Int32Ty, Align - 1);
1010     Addr = CGF.Builder.CreateGEP(Addr, Offset);
1011     llvm::Value *AsInt = CGF.Builder.CreatePtrToInt(Addr,
1012                                                     CGF.Int32Ty);
1013     llvm::Value *Mask = llvm::ConstantInt::get(CGF.Int32Ty, -Align);
1014     Addr = CGF.Builder.CreateIntToPtr(CGF.Builder.CreateAnd(AsInt, Mask),
1015                                       Addr->getType(),
1016                                       "ap.cur.aligned");
1017   }
1018 
1019   llvm::Type *PTy =
1020     llvm::PointerType::getUnqual(CGF.ConvertType(Ty));
1021   llvm::Value *AddrTyped = Builder.CreateBitCast(Addr, PTy);
1022 
1023   uint64_t Offset =
1024     llvm::RoundUpToAlignment(CGF.getContext().getTypeSize(Ty) / 8, Align);
1025   llvm::Value *NextAddr =
1026     Builder.CreateGEP(Addr, llvm::ConstantInt::get(CGF.Int32Ty, Offset),
1027                       "ap.next");
1028   Builder.CreateStore(NextAddr, VAListAddrAsBPP);
1029 
1030   return AddrTyped;
1031 }
1032 
1033 void X86_32TargetCodeGenInfo::SetTargetAttributes(const Decl *D,
1034                                                   llvm::GlobalValue *GV,
1035                                             CodeGen::CodeGenModule &CGM) const {
1036   if (const FunctionDecl *FD = dyn_cast<FunctionDecl>(D)) {
1037     if (FD->hasAttr<X86ForceAlignArgPointerAttr>()) {
1038       // Get the LLVM function.
1039       llvm::Function *Fn = cast<llvm::Function>(GV);
1040 
1041       // Now add the 'alignstack' attribute with a value of 16.
1042       llvm::AttrBuilder B;
1043       B.addStackAlignmentAttr(16);
1044       Fn->addAttributes(llvm::AttributeSet::FunctionIndex,
1045                       llvm::AttributeSet::get(CGM.getLLVMContext(),
1046                                               llvm::AttributeSet::FunctionIndex,
1047                                               B));
1048     }
1049   }
1050 }
1051 
1052 bool X86_32TargetCodeGenInfo::initDwarfEHRegSizeTable(
1053                                                CodeGen::CodeGenFunction &CGF,
1054                                                llvm::Value *Address) const {
1055   CodeGen::CGBuilderTy &Builder = CGF.Builder;
1056 
1057   llvm::Value *Four8 = llvm::ConstantInt::get(CGF.Int8Ty, 4);
1058 
1059   // 0-7 are the eight integer registers;  the order is different
1060   //   on Darwin (for EH), but the range is the same.
1061   // 8 is %eip.
1062   AssignToArrayRange(Builder, Address, Four8, 0, 8);
1063 
1064   if (CGF.CGM.getTarget().getTriple().isOSDarwin()) {
1065     // 12-16 are st(0..4).  Not sure why we stop at 4.
1066     // These have size 16, which is sizeof(long double) on
1067     // platforms with 8-byte alignment for that type.
1068     llvm::Value *Sixteen8 = llvm::ConstantInt::get(CGF.Int8Ty, 16);
1069     AssignToArrayRange(Builder, Address, Sixteen8, 12, 16);
1070 
1071   } else {
1072     // 9 is %eflags, which doesn't get a size on Darwin for some
1073     // reason.
1074     Builder.CreateStore(Four8, Builder.CreateConstInBoundsGEP1_32(Address, 9));
1075 
1076     // 11-16 are st(0..5).  Not sure why we stop at 5.
1077     // These have size 12, which is sizeof(long double) on
1078     // platforms with 4-byte alignment for that type.
1079     llvm::Value *Twelve8 = llvm::ConstantInt::get(CGF.Int8Ty, 12);
1080     AssignToArrayRange(Builder, Address, Twelve8, 11, 16);
1081   }
1082 
1083   return false;
1084 }
1085 
1086 //===----------------------------------------------------------------------===//
1087 // X86-64 ABI Implementation
1088 //===----------------------------------------------------------------------===//
1089 
1090 
1091 namespace {
1092 /// X86_64ABIInfo - The X86_64 ABI information.
1093 class X86_64ABIInfo : public ABIInfo {
1094   enum Class {
1095     Integer = 0,
1096     SSE,
1097     SSEUp,
1098     X87,
1099     X87Up,
1100     ComplexX87,
1101     NoClass,
1102     Memory
1103   };
1104 
1105   /// merge - Implement the X86_64 ABI merging algorithm.
1106   ///
1107   /// Merge an accumulating classification \arg Accum with a field
1108   /// classification \arg Field.
1109   ///
1110   /// \param Accum - The accumulating classification. This should
1111   /// always be either NoClass or the result of a previous merge
1112   /// call. In addition, this should never be Memory (the caller
1113   /// should just return Memory for the aggregate).
1114   static Class merge(Class Accum, Class Field);
1115 
1116   /// postMerge - Implement the X86_64 ABI post merging algorithm.
1117   ///
1118   /// Post merger cleanup, reduces a malformed Hi and Lo pair to
1119   /// final MEMORY or SSE classes when necessary.
1120   ///
1121   /// \param AggregateSize - The size of the current aggregate in
1122   /// the classification process.
1123   ///
1124   /// \param Lo - The classification for the parts of the type
1125   /// residing in the low word of the containing object.
1126   ///
1127   /// \param Hi - The classification for the parts of the type
1128   /// residing in the higher words of the containing object.
1129   ///
1130   void postMerge(unsigned AggregateSize, Class &Lo, Class &Hi) const;
1131 
1132   /// classify - Determine the x86_64 register classes in which the
1133   /// given type T should be passed.
1134   ///
1135   /// \param Lo - The classification for the parts of the type
1136   /// residing in the low word of the containing object.
1137   ///
1138   /// \param Hi - The classification for the parts of the type
1139   /// residing in the high word of the containing object.
1140   ///
1141   /// \param OffsetBase - The bit offset of this type in the
1142   /// containing object.  Some parameters are classified different
1143   /// depending on whether they straddle an eightbyte boundary.
1144   ///
1145   /// \param isNamedArg - Whether the argument in question is a "named"
1146   /// argument, as used in AMD64-ABI 3.5.7.
1147   ///
1148   /// If a word is unused its result will be NoClass; if a type should
1149   /// be passed in Memory then at least the classification of \arg Lo
1150   /// will be Memory.
1151   ///
1152   /// The \arg Lo class will be NoClass iff the argument is ignored.
1153   ///
1154   /// If the \arg Lo class is ComplexX87, then the \arg Hi class will
1155   /// also be ComplexX87.
1156   void classify(QualType T, uint64_t OffsetBase, Class &Lo, Class &Hi,
1157                 bool isNamedArg) const;
1158 
1159   llvm::Type *GetByteVectorType(QualType Ty) const;
1160   llvm::Type *GetSSETypeAtOffset(llvm::Type *IRType,
1161                                  unsigned IROffset, QualType SourceTy,
1162                                  unsigned SourceOffset) const;
1163   llvm::Type *GetINTEGERTypeAtOffset(llvm::Type *IRType,
1164                                      unsigned IROffset, QualType SourceTy,
1165                                      unsigned SourceOffset) const;
1166 
1167   /// getIndirectResult - Give a source type \arg Ty, return a suitable result
1168   /// such that the argument will be returned in memory.
1169   ABIArgInfo getIndirectReturnResult(QualType Ty) const;
1170 
1171   /// getIndirectResult - Give a source type \arg Ty, return a suitable result
1172   /// such that the argument will be passed in memory.
1173   ///
1174   /// \param freeIntRegs - The number of free integer registers remaining
1175   /// available.
1176   ABIArgInfo getIndirectResult(QualType Ty, unsigned freeIntRegs) const;
1177 
1178   ABIArgInfo classifyReturnType(QualType RetTy) const;
1179 
1180   ABIArgInfo classifyArgumentType(QualType Ty,
1181                                   unsigned freeIntRegs,
1182                                   unsigned &neededInt,
1183                                   unsigned &neededSSE,
1184                                   bool isNamedArg) const;
1185 
1186   bool IsIllegalVectorType(QualType Ty) const;
1187 
1188   /// The 0.98 ABI revision clarified a lot of ambiguities,
1189   /// unfortunately in ways that were not always consistent with
1190   /// certain previous compilers.  In particular, platforms which
1191   /// required strict binary compatibility with older versions of GCC
1192   /// may need to exempt themselves.
1193   bool honorsRevision0_98() const {
1194     return !getTarget().getTriple().isOSDarwin();
1195   }
1196 
1197   bool HasAVX;
1198   // Some ABIs (e.g. X32 ABI and Native Client OS) use 32 bit pointers on
1199   // 64-bit hardware.
1200   bool Has64BitPointers;
1201 
1202 public:
1203   X86_64ABIInfo(CodeGen::CodeGenTypes &CGT, bool hasavx) :
1204       ABIInfo(CGT), HasAVX(hasavx),
1205       Has64BitPointers(CGT.getDataLayout().getPointerSize(0) == 8) {
1206   }
1207 
1208   bool isPassedUsingAVXType(QualType type) const {
1209     unsigned neededInt, neededSSE;
1210     // The freeIntRegs argument doesn't matter here.
1211     ABIArgInfo info = classifyArgumentType(type, 0, neededInt, neededSSE,
1212                                            /*isNamedArg*/true);
1213     if (info.isDirect()) {
1214       llvm::Type *ty = info.getCoerceToType();
1215       if (llvm::VectorType *vectorTy = dyn_cast_or_null<llvm::VectorType>(ty))
1216         return (vectorTy->getBitWidth() > 128);
1217     }
1218     return false;
1219   }
1220 
1221   virtual void computeInfo(CGFunctionInfo &FI) const;
1222 
1223   virtual llvm::Value *EmitVAArg(llvm::Value *VAListAddr, QualType Ty,
1224                                  CodeGenFunction &CGF) const;
1225 };
1226 
1227 /// WinX86_64ABIInfo - The Windows X86_64 ABI information.
1228 class WinX86_64ABIInfo : public ABIInfo {
1229 
1230   ABIArgInfo classify(QualType Ty, bool IsReturnType) const;
1231 
1232 public:
1233   WinX86_64ABIInfo(CodeGen::CodeGenTypes &CGT) : ABIInfo(CGT) {}
1234 
1235   virtual void computeInfo(CGFunctionInfo &FI) const;
1236 
1237   virtual llvm::Value *EmitVAArg(llvm::Value *VAListAddr, QualType Ty,
1238                                  CodeGenFunction &CGF) const;
1239 };
1240 
1241 class X86_64TargetCodeGenInfo : public TargetCodeGenInfo {
1242 public:
1243   X86_64TargetCodeGenInfo(CodeGen::CodeGenTypes &CGT, bool HasAVX)
1244       : TargetCodeGenInfo(new X86_64ABIInfo(CGT, HasAVX)) {}
1245 
1246   const X86_64ABIInfo &getABIInfo() const {
1247     return static_cast<const X86_64ABIInfo&>(TargetCodeGenInfo::getABIInfo());
1248   }
1249 
1250   int getDwarfEHStackPointer(CodeGen::CodeGenModule &CGM) const {
1251     return 7;
1252   }
1253 
1254   bool initDwarfEHRegSizeTable(CodeGen::CodeGenFunction &CGF,
1255                                llvm::Value *Address) const {
1256     llvm::Value *Eight8 = llvm::ConstantInt::get(CGF.Int8Ty, 8);
1257 
1258     // 0-15 are the 16 integer registers.
1259     // 16 is %rip.
1260     AssignToArrayRange(CGF.Builder, Address, Eight8, 0, 16);
1261     return false;
1262   }
1263 
1264   llvm::Type* adjustInlineAsmType(CodeGen::CodeGenFunction &CGF,
1265                                   StringRef Constraint,
1266                                   llvm::Type* Ty) const {
1267     return X86AdjustInlineAsmType(CGF, Constraint, Ty);
1268   }
1269 
1270   bool isNoProtoCallVariadic(const CallArgList &args,
1271                              const FunctionNoProtoType *fnType) const {
1272     // The default CC on x86-64 sets %al to the number of SSA
1273     // registers used, and GCC sets this when calling an unprototyped
1274     // function, so we override the default behavior.  However, don't do
1275     // that when AVX types are involved: the ABI explicitly states it is
1276     // undefined, and it doesn't work in practice because of how the ABI
1277     // defines varargs anyway.
1278     if (fnType->getCallConv() == CC_C) {
1279       bool HasAVXType = false;
1280       for (CallArgList::const_iterator
1281              it = args.begin(), ie = args.end(); it != ie; ++it) {
1282         if (getABIInfo().isPassedUsingAVXType(it->Ty)) {
1283           HasAVXType = true;
1284           break;
1285         }
1286       }
1287 
1288       if (!HasAVXType)
1289         return true;
1290     }
1291 
1292     return TargetCodeGenInfo::isNoProtoCallVariadic(args, fnType);
1293   }
1294 
1295   llvm::Constant *getUBSanFunctionSignature(CodeGen::CodeGenModule &CGM) const {
1296     unsigned Sig = (0xeb << 0) |  // jmp rel8
1297                    (0x0a << 8) |  //           .+0x0c
1298                    ('F' << 16) |
1299                    ('T' << 24);
1300     return llvm::ConstantInt::get(CGM.Int32Ty, Sig);
1301   }
1302 
1303 };
1304 
1305 static std::string qualifyWindowsLibrary(llvm::StringRef Lib) {
1306   // If the argument does not end in .lib, automatically add the suffix. This
1307   // matches the behavior of MSVC.
1308   std::string ArgStr = Lib;
1309   if (Lib.size() <= 4 ||
1310       Lib.substr(Lib.size() - 4).compare_lower(".lib") != 0) {
1311     ArgStr += ".lib";
1312   }
1313   return ArgStr;
1314 }
1315 
1316 class WinX86_32TargetCodeGenInfo : public X86_32TargetCodeGenInfo {
1317 public:
1318   WinX86_32TargetCodeGenInfo(CodeGen::CodeGenTypes &CGT,
1319         bool d, bool p, bool w, unsigned RegParms)
1320     : X86_32TargetCodeGenInfo(CGT, d, p, w, RegParms) {}
1321 
1322   void getDependentLibraryOption(llvm::StringRef Lib,
1323                                  llvm::SmallString<24> &Opt) const {
1324     Opt = "/DEFAULTLIB:";
1325     Opt += qualifyWindowsLibrary(Lib);
1326   }
1327 
1328   void getDetectMismatchOption(llvm::StringRef Name,
1329                                llvm::StringRef Value,
1330                                llvm::SmallString<32> &Opt) const {
1331     Opt = "/FAILIFMISMATCH:\"" + Name.str() + "=" + Value.str() + "\"";
1332   }
1333 };
1334 
1335 class WinX86_64TargetCodeGenInfo : public TargetCodeGenInfo {
1336 public:
1337   WinX86_64TargetCodeGenInfo(CodeGen::CodeGenTypes &CGT)
1338     : TargetCodeGenInfo(new WinX86_64ABIInfo(CGT)) {}
1339 
1340   int getDwarfEHStackPointer(CodeGen::CodeGenModule &CGM) const {
1341     return 7;
1342   }
1343 
1344   bool initDwarfEHRegSizeTable(CodeGen::CodeGenFunction &CGF,
1345                                llvm::Value *Address) const {
1346     llvm::Value *Eight8 = llvm::ConstantInt::get(CGF.Int8Ty, 8);
1347 
1348     // 0-15 are the 16 integer registers.
1349     // 16 is %rip.
1350     AssignToArrayRange(CGF.Builder, Address, Eight8, 0, 16);
1351     return false;
1352   }
1353 
1354   void getDependentLibraryOption(llvm::StringRef Lib,
1355                                  llvm::SmallString<24> &Opt) const {
1356     Opt = "/DEFAULTLIB:";
1357     Opt += qualifyWindowsLibrary(Lib);
1358   }
1359 
1360   void getDetectMismatchOption(llvm::StringRef Name,
1361                                llvm::StringRef Value,
1362                                llvm::SmallString<32> &Opt) const {
1363     Opt = "/FAILIFMISMATCH:\"" + Name.str() + "=" + Value.str() + "\"";
1364   }
1365 };
1366 
1367 }
1368 
1369 void X86_64ABIInfo::postMerge(unsigned AggregateSize, Class &Lo,
1370                               Class &Hi) const {
1371   // AMD64-ABI 3.2.3p2: Rule 5. Then a post merger cleanup is done:
1372   //
1373   // (a) If one of the classes is Memory, the whole argument is passed in
1374   //     memory.
1375   //
1376   // (b) If X87UP is not preceded by X87, the whole argument is passed in
1377   //     memory.
1378   //
1379   // (c) If the size of the aggregate exceeds two eightbytes and the first
1380   //     eightbyte isn't SSE or any other eightbyte isn't SSEUP, the whole
1381   //     argument is passed in memory. NOTE: This is necessary to keep the
1382   //     ABI working for processors that don't support the __m256 type.
1383   //
1384   // (d) If SSEUP is not preceded by SSE or SSEUP, it is converted to SSE.
1385   //
1386   // Some of these are enforced by the merging logic.  Others can arise
1387   // only with unions; for example:
1388   //   union { _Complex double; unsigned; }
1389   //
1390   // Note that clauses (b) and (c) were added in 0.98.
1391   //
1392   if (Hi == Memory)
1393     Lo = Memory;
1394   if (Hi == X87Up && Lo != X87 && honorsRevision0_98())
1395     Lo = Memory;
1396   if (AggregateSize > 128 && (Lo != SSE || Hi != SSEUp))
1397     Lo = Memory;
1398   if (Hi == SSEUp && Lo != SSE)
1399     Hi = SSE;
1400 }
1401 
1402 X86_64ABIInfo::Class X86_64ABIInfo::merge(Class Accum, Class Field) {
1403   // AMD64-ABI 3.2.3p2: Rule 4. Each field of an object is
1404   // classified recursively so that always two fields are
1405   // considered. The resulting class is calculated according to
1406   // the classes of the fields in the eightbyte:
1407   //
1408   // (a) If both classes are equal, this is the resulting class.
1409   //
1410   // (b) If one of the classes is NO_CLASS, the resulting class is
1411   // the other class.
1412   //
1413   // (c) If one of the classes is MEMORY, the result is the MEMORY
1414   // class.
1415   //
1416   // (d) If one of the classes is INTEGER, the result is the
1417   // INTEGER.
1418   //
1419   // (e) If one of the classes is X87, X87UP, COMPLEX_X87 class,
1420   // MEMORY is used as class.
1421   //
1422   // (f) Otherwise class SSE is used.
1423 
1424   // Accum should never be memory (we should have returned) or
1425   // ComplexX87 (because this cannot be passed in a structure).
1426   assert((Accum != Memory && Accum != ComplexX87) &&
1427          "Invalid accumulated classification during merge.");
1428   if (Accum == Field || Field == NoClass)
1429     return Accum;
1430   if (Field == Memory)
1431     return Memory;
1432   if (Accum == NoClass)
1433     return Field;
1434   if (Accum == Integer || Field == Integer)
1435     return Integer;
1436   if (Field == X87 || Field == X87Up || Field == ComplexX87 ||
1437       Accum == X87 || Accum == X87Up)
1438     return Memory;
1439   return SSE;
1440 }
1441 
1442 void X86_64ABIInfo::classify(QualType Ty, uint64_t OffsetBase,
1443                              Class &Lo, Class &Hi, bool isNamedArg) const {
1444   // FIXME: This code can be simplified by introducing a simple value class for
1445   // Class pairs with appropriate constructor methods for the various
1446   // situations.
1447 
1448   // FIXME: Some of the split computations are wrong; unaligned vectors
1449   // shouldn't be passed in registers for example, so there is no chance they
1450   // can straddle an eightbyte. Verify & simplify.
1451 
1452   Lo = Hi = NoClass;
1453 
1454   Class &Current = OffsetBase < 64 ? Lo : Hi;
1455   Current = Memory;
1456 
1457   if (const BuiltinType *BT = Ty->getAs<BuiltinType>()) {
1458     BuiltinType::Kind k = BT->getKind();
1459 
1460     if (k == BuiltinType::Void) {
1461       Current = NoClass;
1462     } else if (k == BuiltinType::Int128 || k == BuiltinType::UInt128) {
1463       Lo = Integer;
1464       Hi = Integer;
1465     } else if (k >= BuiltinType::Bool && k <= BuiltinType::LongLong) {
1466       Current = Integer;
1467     } else if ((k == BuiltinType::Float || k == BuiltinType::Double) ||
1468                (k == BuiltinType::LongDouble &&
1469                 getTarget().getTriple().isOSNaCl())) {
1470       Current = SSE;
1471     } else if (k == BuiltinType::LongDouble) {
1472       Lo = X87;
1473       Hi = X87Up;
1474     }
1475     // FIXME: _Decimal32 and _Decimal64 are SSE.
1476     // FIXME: _float128 and _Decimal128 are (SSE, SSEUp).
1477     return;
1478   }
1479 
1480   if (const EnumType *ET = Ty->getAs<EnumType>()) {
1481     // Classify the underlying integer type.
1482     classify(ET->getDecl()->getIntegerType(), OffsetBase, Lo, Hi, isNamedArg);
1483     return;
1484   }
1485 
1486   if (Ty->hasPointerRepresentation()) {
1487     Current = Integer;
1488     return;
1489   }
1490 
1491   if (Ty->isMemberPointerType()) {
1492     if (Ty->isMemberFunctionPointerType() && Has64BitPointers)
1493       Lo = Hi = Integer;
1494     else
1495       Current = Integer;
1496     return;
1497   }
1498 
1499   if (const VectorType *VT = Ty->getAs<VectorType>()) {
1500     uint64_t Size = getContext().getTypeSize(VT);
1501     if (Size == 32) {
1502       // gcc passes all <4 x char>, <2 x short>, <1 x int>, <1 x
1503       // float> as integer.
1504       Current = Integer;
1505 
1506       // If this type crosses an eightbyte boundary, it should be
1507       // split.
1508       uint64_t EB_Real = (OffsetBase) / 64;
1509       uint64_t EB_Imag = (OffsetBase + Size - 1) / 64;
1510       if (EB_Real != EB_Imag)
1511         Hi = Lo;
1512     } else if (Size == 64) {
1513       // gcc passes <1 x double> in memory. :(
1514       if (VT->getElementType()->isSpecificBuiltinType(BuiltinType::Double))
1515         return;
1516 
1517       // gcc passes <1 x long long> as INTEGER.
1518       if (VT->getElementType()->isSpecificBuiltinType(BuiltinType::LongLong) ||
1519           VT->getElementType()->isSpecificBuiltinType(BuiltinType::ULongLong) ||
1520           VT->getElementType()->isSpecificBuiltinType(BuiltinType::Long) ||
1521           VT->getElementType()->isSpecificBuiltinType(BuiltinType::ULong))
1522         Current = Integer;
1523       else
1524         Current = SSE;
1525 
1526       // If this type crosses an eightbyte boundary, it should be
1527       // split.
1528       if (OffsetBase && OffsetBase != 64)
1529         Hi = Lo;
1530     } else if (Size == 128 || (HasAVX && isNamedArg && Size == 256)) {
1531       // Arguments of 256-bits are split into four eightbyte chunks. The
1532       // least significant one belongs to class SSE and all the others to class
1533       // SSEUP. The original Lo and Hi design considers that types can't be
1534       // greater than 128-bits, so a 64-bit split in Hi and Lo makes sense.
1535       // This design isn't correct for 256-bits, but since there're no cases
1536       // where the upper parts would need to be inspected, avoid adding
1537       // complexity and just consider Hi to match the 64-256 part.
1538       //
1539       // Note that per 3.5.7 of AMD64-ABI, 256-bit args are only passed in
1540       // registers if they are "named", i.e. not part of the "..." of a
1541       // variadic function.
1542       Lo = SSE;
1543       Hi = SSEUp;
1544     }
1545     return;
1546   }
1547 
1548   if (const ComplexType *CT = Ty->getAs<ComplexType>()) {
1549     QualType ET = getContext().getCanonicalType(CT->getElementType());
1550 
1551     uint64_t Size = getContext().getTypeSize(Ty);
1552     if (ET->isIntegralOrEnumerationType()) {
1553       if (Size <= 64)
1554         Current = Integer;
1555       else if (Size <= 128)
1556         Lo = Hi = Integer;
1557     } else if (ET == getContext().FloatTy)
1558       Current = SSE;
1559     else if (ET == getContext().DoubleTy ||
1560              (ET == getContext().LongDoubleTy &&
1561               getTarget().getTriple().isOSNaCl()))
1562       Lo = Hi = SSE;
1563     else if (ET == getContext().LongDoubleTy)
1564       Current = ComplexX87;
1565 
1566     // If this complex type crosses an eightbyte boundary then it
1567     // should be split.
1568     uint64_t EB_Real = (OffsetBase) / 64;
1569     uint64_t EB_Imag = (OffsetBase + getContext().getTypeSize(ET)) / 64;
1570     if (Hi == NoClass && EB_Real != EB_Imag)
1571       Hi = Lo;
1572 
1573     return;
1574   }
1575 
1576   if (const ConstantArrayType *AT = getContext().getAsConstantArrayType(Ty)) {
1577     // Arrays are treated like structures.
1578 
1579     uint64_t Size = getContext().getTypeSize(Ty);
1580 
1581     // AMD64-ABI 3.2.3p2: Rule 1. If the size of an object is larger
1582     // than four eightbytes, ..., it has class MEMORY.
1583     if (Size > 256)
1584       return;
1585 
1586     // AMD64-ABI 3.2.3p2: Rule 1. If ..., or it contains unaligned
1587     // fields, it has class MEMORY.
1588     //
1589     // Only need to check alignment of array base.
1590     if (OffsetBase % getContext().getTypeAlign(AT->getElementType()))
1591       return;
1592 
1593     // Otherwise implement simplified merge. We could be smarter about
1594     // this, but it isn't worth it and would be harder to verify.
1595     Current = NoClass;
1596     uint64_t EltSize = getContext().getTypeSize(AT->getElementType());
1597     uint64_t ArraySize = AT->getSize().getZExtValue();
1598 
1599     // The only case a 256-bit wide vector could be used is when the array
1600     // contains a single 256-bit element. Since Lo and Hi logic isn't extended
1601     // to work for sizes wider than 128, early check and fallback to memory.
1602     if (Size > 128 && EltSize != 256)
1603       return;
1604 
1605     for (uint64_t i=0, Offset=OffsetBase; i<ArraySize; ++i, Offset += EltSize) {
1606       Class FieldLo, FieldHi;
1607       classify(AT->getElementType(), Offset, FieldLo, FieldHi, isNamedArg);
1608       Lo = merge(Lo, FieldLo);
1609       Hi = merge(Hi, FieldHi);
1610       if (Lo == Memory || Hi == Memory)
1611         break;
1612     }
1613 
1614     postMerge(Size, Lo, Hi);
1615     assert((Hi != SSEUp || Lo == SSE) && "Invalid SSEUp array classification.");
1616     return;
1617   }
1618 
1619   if (const RecordType *RT = Ty->getAs<RecordType>()) {
1620     uint64_t Size = getContext().getTypeSize(Ty);
1621 
1622     // AMD64-ABI 3.2.3p2: Rule 1. If the size of an object is larger
1623     // than four eightbytes, ..., it has class MEMORY.
1624     if (Size > 256)
1625       return;
1626 
1627     // AMD64-ABI 3.2.3p2: Rule 2. If a C++ object has either a non-trivial
1628     // copy constructor or a non-trivial destructor, it is passed by invisible
1629     // reference.
1630     if (getRecordArgABI(RT, getCXXABI()))
1631       return;
1632 
1633     const RecordDecl *RD = RT->getDecl();
1634 
1635     // Assume variable sized types are passed in memory.
1636     if (RD->hasFlexibleArrayMember())
1637       return;
1638 
1639     const ASTRecordLayout &Layout = getContext().getASTRecordLayout(RD);
1640 
1641     // Reset Lo class, this will be recomputed.
1642     Current = NoClass;
1643 
1644     // If this is a C++ record, classify the bases first.
1645     if (const CXXRecordDecl *CXXRD = dyn_cast<CXXRecordDecl>(RD)) {
1646       for (CXXRecordDecl::base_class_const_iterator i = CXXRD->bases_begin(),
1647              e = CXXRD->bases_end(); i != e; ++i) {
1648         assert(!i->isVirtual() && !i->getType()->isDependentType() &&
1649                "Unexpected base class!");
1650         const CXXRecordDecl *Base =
1651           cast<CXXRecordDecl>(i->getType()->getAs<RecordType>()->getDecl());
1652 
1653         // Classify this field.
1654         //
1655         // AMD64-ABI 3.2.3p2: Rule 3. If the size of the aggregate exceeds a
1656         // single eightbyte, each is classified separately. Each eightbyte gets
1657         // initialized to class NO_CLASS.
1658         Class FieldLo, FieldHi;
1659         uint64_t Offset =
1660           OffsetBase + getContext().toBits(Layout.getBaseClassOffset(Base));
1661         classify(i->getType(), Offset, FieldLo, FieldHi, isNamedArg);
1662         Lo = merge(Lo, FieldLo);
1663         Hi = merge(Hi, FieldHi);
1664         if (Lo == Memory || Hi == Memory)
1665           break;
1666       }
1667     }
1668 
1669     // Classify the fields one at a time, merging the results.
1670     unsigned idx = 0;
1671     for (RecordDecl::field_iterator i = RD->field_begin(), e = RD->field_end();
1672            i != e; ++i, ++idx) {
1673       uint64_t Offset = OffsetBase + Layout.getFieldOffset(idx);
1674       bool BitField = i->isBitField();
1675 
1676       // AMD64-ABI 3.2.3p2: Rule 1. If the size of an object is larger than
1677       // four eightbytes, or it contains unaligned fields, it has class MEMORY.
1678       //
1679       // The only case a 256-bit wide vector could be used is when the struct
1680       // contains a single 256-bit element. Since Lo and Hi logic isn't extended
1681       // to work for sizes wider than 128, early check and fallback to memory.
1682       //
1683       if (Size > 128 && getContext().getTypeSize(i->getType()) != 256) {
1684         Lo = Memory;
1685         return;
1686       }
1687       // Note, skip this test for bit-fields, see below.
1688       if (!BitField && Offset % getContext().getTypeAlign(i->getType())) {
1689         Lo = Memory;
1690         return;
1691       }
1692 
1693       // Classify this field.
1694       //
1695       // AMD64-ABI 3.2.3p2: Rule 3. If the size of the aggregate
1696       // exceeds a single eightbyte, each is classified
1697       // separately. Each eightbyte gets initialized to class
1698       // NO_CLASS.
1699       Class FieldLo, FieldHi;
1700 
1701       // Bit-fields require special handling, they do not force the
1702       // structure to be passed in memory even if unaligned, and
1703       // therefore they can straddle an eightbyte.
1704       if (BitField) {
1705         // Ignore padding bit-fields.
1706         if (i->isUnnamedBitfield())
1707           continue;
1708 
1709         uint64_t Offset = OffsetBase + Layout.getFieldOffset(idx);
1710         uint64_t Size = i->getBitWidthValue(getContext());
1711 
1712         uint64_t EB_Lo = Offset / 64;
1713         uint64_t EB_Hi = (Offset + Size - 1) / 64;
1714 
1715         if (EB_Lo) {
1716           assert(EB_Hi == EB_Lo && "Invalid classification, type > 16 bytes.");
1717           FieldLo = NoClass;
1718           FieldHi = Integer;
1719         } else {
1720           FieldLo = Integer;
1721           FieldHi = EB_Hi ? Integer : NoClass;
1722         }
1723       } else
1724         classify(i->getType(), Offset, FieldLo, FieldHi, isNamedArg);
1725       Lo = merge(Lo, FieldLo);
1726       Hi = merge(Hi, FieldHi);
1727       if (Lo == Memory || Hi == Memory)
1728         break;
1729     }
1730 
1731     postMerge(Size, Lo, Hi);
1732   }
1733 }
1734 
1735 ABIArgInfo X86_64ABIInfo::getIndirectReturnResult(QualType Ty) const {
1736   // If this is a scalar LLVM value then assume LLVM will pass it in the right
1737   // place naturally.
1738   if (!isAggregateTypeForABI(Ty)) {
1739     // Treat an enum type as its underlying type.
1740     if (const EnumType *EnumTy = Ty->getAs<EnumType>())
1741       Ty = EnumTy->getDecl()->getIntegerType();
1742 
1743     return (Ty->isPromotableIntegerType() ?
1744             ABIArgInfo::getExtend() : ABIArgInfo::getDirect());
1745   }
1746 
1747   return ABIArgInfo::getIndirect(0);
1748 }
1749 
1750 bool X86_64ABIInfo::IsIllegalVectorType(QualType Ty) const {
1751   if (const VectorType *VecTy = Ty->getAs<VectorType>()) {
1752     uint64_t Size = getContext().getTypeSize(VecTy);
1753     unsigned LargestVector = HasAVX ? 256 : 128;
1754     if (Size <= 64 || Size > LargestVector)
1755       return true;
1756   }
1757 
1758   return false;
1759 }
1760 
1761 ABIArgInfo X86_64ABIInfo::getIndirectResult(QualType Ty,
1762                                             unsigned freeIntRegs) const {
1763   // If this is a scalar LLVM value then assume LLVM will pass it in the right
1764   // place naturally.
1765   //
1766   // This assumption is optimistic, as there could be free registers available
1767   // when we need to pass this argument in memory, and LLVM could try to pass
1768   // the argument in the free register. This does not seem to happen currently,
1769   // but this code would be much safer if we could mark the argument with
1770   // 'onstack'. See PR12193.
1771   if (!isAggregateTypeForABI(Ty) && !IsIllegalVectorType(Ty)) {
1772     // Treat an enum type as its underlying type.
1773     if (const EnumType *EnumTy = Ty->getAs<EnumType>())
1774       Ty = EnumTy->getDecl()->getIntegerType();
1775 
1776     return (Ty->isPromotableIntegerType() ?
1777             ABIArgInfo::getExtend() : ABIArgInfo::getDirect());
1778   }
1779 
1780   if (CGCXXABI::RecordArgABI RAA = getRecordArgABI(Ty, getCXXABI()))
1781     return ABIArgInfo::getIndirect(0, RAA == CGCXXABI::RAA_DirectInMemory);
1782 
1783   // Compute the byval alignment. We specify the alignment of the byval in all
1784   // cases so that the mid-level optimizer knows the alignment of the byval.
1785   unsigned Align = std::max(getContext().getTypeAlign(Ty) / 8, 8U);
1786 
1787   // Attempt to avoid passing indirect results using byval when possible. This
1788   // is important for good codegen.
1789   //
1790   // We do this by coercing the value into a scalar type which the backend can
1791   // handle naturally (i.e., without using byval).
1792   //
1793   // For simplicity, we currently only do this when we have exhausted all of the
1794   // free integer registers. Doing this when there are free integer registers
1795   // would require more care, as we would have to ensure that the coerced value
1796   // did not claim the unused register. That would require either reording the
1797   // arguments to the function (so that any subsequent inreg values came first),
1798   // or only doing this optimization when there were no following arguments that
1799   // might be inreg.
1800   //
1801   // We currently expect it to be rare (particularly in well written code) for
1802   // arguments to be passed on the stack when there are still free integer
1803   // registers available (this would typically imply large structs being passed
1804   // by value), so this seems like a fair tradeoff for now.
1805   //
1806   // We can revisit this if the backend grows support for 'onstack' parameter
1807   // attributes. See PR12193.
1808   if (freeIntRegs == 0) {
1809     uint64_t Size = getContext().getTypeSize(Ty);
1810 
1811     // If this type fits in an eightbyte, coerce it into the matching integral
1812     // type, which will end up on the stack (with alignment 8).
1813     if (Align == 8 && Size <= 64)
1814       return ABIArgInfo::getDirect(llvm::IntegerType::get(getVMContext(),
1815                                                           Size));
1816   }
1817 
1818   return ABIArgInfo::getIndirect(Align);
1819 }
1820 
1821 /// GetByteVectorType - The ABI specifies that a value should be passed in an
1822 /// full vector XMM/YMM register.  Pick an LLVM IR type that will be passed as a
1823 /// vector register.
1824 llvm::Type *X86_64ABIInfo::GetByteVectorType(QualType Ty) const {
1825   llvm::Type *IRType = CGT.ConvertType(Ty);
1826 
1827   // Wrapper structs that just contain vectors are passed just like vectors,
1828   // strip them off if present.
1829   llvm::StructType *STy = dyn_cast<llvm::StructType>(IRType);
1830   while (STy && STy->getNumElements() == 1) {
1831     IRType = STy->getElementType(0);
1832     STy = dyn_cast<llvm::StructType>(IRType);
1833   }
1834 
1835   // If the preferred type is a 16-byte vector, prefer to pass it.
1836   if (llvm::VectorType *VT = dyn_cast<llvm::VectorType>(IRType)){
1837     llvm::Type *EltTy = VT->getElementType();
1838     unsigned BitWidth = VT->getBitWidth();
1839     if ((BitWidth >= 128 && BitWidth <= 256) &&
1840         (EltTy->isFloatTy() || EltTy->isDoubleTy() ||
1841          EltTy->isIntegerTy(8) || EltTy->isIntegerTy(16) ||
1842          EltTy->isIntegerTy(32) || EltTy->isIntegerTy(64) ||
1843          EltTy->isIntegerTy(128)))
1844       return VT;
1845   }
1846 
1847   return llvm::VectorType::get(llvm::Type::getDoubleTy(getVMContext()), 2);
1848 }
1849 
1850 /// BitsContainNoUserData - Return true if the specified [start,end) bit range
1851 /// is known to either be off the end of the specified type or being in
1852 /// alignment padding.  The user type specified is known to be at most 128 bits
1853 /// in size, and have passed through X86_64ABIInfo::classify with a successful
1854 /// classification that put one of the two halves in the INTEGER class.
1855 ///
1856 /// It is conservatively correct to return false.
1857 static bool BitsContainNoUserData(QualType Ty, unsigned StartBit,
1858                                   unsigned EndBit, ASTContext &Context) {
1859   // If the bytes being queried are off the end of the type, there is no user
1860   // data hiding here.  This handles analysis of builtins, vectors and other
1861   // types that don't contain interesting padding.
1862   unsigned TySize = (unsigned)Context.getTypeSize(Ty);
1863   if (TySize <= StartBit)
1864     return true;
1865 
1866   if (const ConstantArrayType *AT = Context.getAsConstantArrayType(Ty)) {
1867     unsigned EltSize = (unsigned)Context.getTypeSize(AT->getElementType());
1868     unsigned NumElts = (unsigned)AT->getSize().getZExtValue();
1869 
1870     // Check each element to see if the element overlaps with the queried range.
1871     for (unsigned i = 0; i != NumElts; ++i) {
1872       // If the element is after the span we care about, then we're done..
1873       unsigned EltOffset = i*EltSize;
1874       if (EltOffset >= EndBit) break;
1875 
1876       unsigned EltStart = EltOffset < StartBit ? StartBit-EltOffset :0;
1877       if (!BitsContainNoUserData(AT->getElementType(), EltStart,
1878                                  EndBit-EltOffset, Context))
1879         return false;
1880     }
1881     // If it overlaps no elements, then it is safe to process as padding.
1882     return true;
1883   }
1884 
1885   if (const RecordType *RT = Ty->getAs<RecordType>()) {
1886     const RecordDecl *RD = RT->getDecl();
1887     const ASTRecordLayout &Layout = Context.getASTRecordLayout(RD);
1888 
1889     // If this is a C++ record, check the bases first.
1890     if (const CXXRecordDecl *CXXRD = dyn_cast<CXXRecordDecl>(RD)) {
1891       for (CXXRecordDecl::base_class_const_iterator i = CXXRD->bases_begin(),
1892            e = CXXRD->bases_end(); i != e; ++i) {
1893         assert(!i->isVirtual() && !i->getType()->isDependentType() &&
1894                "Unexpected base class!");
1895         const CXXRecordDecl *Base =
1896           cast<CXXRecordDecl>(i->getType()->getAs<RecordType>()->getDecl());
1897 
1898         // If the base is after the span we care about, ignore it.
1899         unsigned BaseOffset = Context.toBits(Layout.getBaseClassOffset(Base));
1900         if (BaseOffset >= EndBit) continue;
1901 
1902         unsigned BaseStart = BaseOffset < StartBit ? StartBit-BaseOffset :0;
1903         if (!BitsContainNoUserData(i->getType(), BaseStart,
1904                                    EndBit-BaseOffset, Context))
1905           return false;
1906       }
1907     }
1908 
1909     // Verify that no field has data that overlaps the region of interest.  Yes
1910     // this could be sped up a lot by being smarter about queried fields,
1911     // however we're only looking at structs up to 16 bytes, so we don't care
1912     // much.
1913     unsigned idx = 0;
1914     for (RecordDecl::field_iterator i = RD->field_begin(), e = RD->field_end();
1915          i != e; ++i, ++idx) {
1916       unsigned FieldOffset = (unsigned)Layout.getFieldOffset(idx);
1917 
1918       // If we found a field after the region we care about, then we're done.
1919       if (FieldOffset >= EndBit) break;
1920 
1921       unsigned FieldStart = FieldOffset < StartBit ? StartBit-FieldOffset :0;
1922       if (!BitsContainNoUserData(i->getType(), FieldStart, EndBit-FieldOffset,
1923                                  Context))
1924         return false;
1925     }
1926 
1927     // If nothing in this record overlapped the area of interest, then we're
1928     // clean.
1929     return true;
1930   }
1931 
1932   return false;
1933 }
1934 
1935 /// ContainsFloatAtOffset - Return true if the specified LLVM IR type has a
1936 /// float member at the specified offset.  For example, {int,{float}} has a
1937 /// float at offset 4.  It is conservatively correct for this routine to return
1938 /// false.
1939 static bool ContainsFloatAtOffset(llvm::Type *IRType, unsigned IROffset,
1940                                   const llvm::DataLayout &TD) {
1941   // Base case if we find a float.
1942   if (IROffset == 0 && IRType->isFloatTy())
1943     return true;
1944 
1945   // If this is a struct, recurse into the field at the specified offset.
1946   if (llvm::StructType *STy = dyn_cast<llvm::StructType>(IRType)) {
1947     const llvm::StructLayout *SL = TD.getStructLayout(STy);
1948     unsigned Elt = SL->getElementContainingOffset(IROffset);
1949     IROffset -= SL->getElementOffset(Elt);
1950     return ContainsFloatAtOffset(STy->getElementType(Elt), IROffset, TD);
1951   }
1952 
1953   // If this is an array, recurse into the field at the specified offset.
1954   if (llvm::ArrayType *ATy = dyn_cast<llvm::ArrayType>(IRType)) {
1955     llvm::Type *EltTy = ATy->getElementType();
1956     unsigned EltSize = TD.getTypeAllocSize(EltTy);
1957     IROffset -= IROffset/EltSize*EltSize;
1958     return ContainsFloatAtOffset(EltTy, IROffset, TD);
1959   }
1960 
1961   return false;
1962 }
1963 
1964 
1965 /// GetSSETypeAtOffset - Return a type that will be passed by the backend in the
1966 /// low 8 bytes of an XMM register, corresponding to the SSE class.
1967 llvm::Type *X86_64ABIInfo::
1968 GetSSETypeAtOffset(llvm::Type *IRType, unsigned IROffset,
1969                    QualType SourceTy, unsigned SourceOffset) const {
1970   // The only three choices we have are either double, <2 x float>, or float. We
1971   // pass as float if the last 4 bytes is just padding.  This happens for
1972   // structs that contain 3 floats.
1973   if (BitsContainNoUserData(SourceTy, SourceOffset*8+32,
1974                             SourceOffset*8+64, getContext()))
1975     return llvm::Type::getFloatTy(getVMContext());
1976 
1977   // We want to pass as <2 x float> if the LLVM IR type contains a float at
1978   // offset+0 and offset+4.  Walk the LLVM IR type to find out if this is the
1979   // case.
1980   if (ContainsFloatAtOffset(IRType, IROffset, getDataLayout()) &&
1981       ContainsFloatAtOffset(IRType, IROffset+4, getDataLayout()))
1982     return llvm::VectorType::get(llvm::Type::getFloatTy(getVMContext()), 2);
1983 
1984   return llvm::Type::getDoubleTy(getVMContext());
1985 }
1986 
1987 
1988 /// GetINTEGERTypeAtOffset - The ABI specifies that a value should be passed in
1989 /// an 8-byte GPR.  This means that we either have a scalar or we are talking
1990 /// about the high or low part of an up-to-16-byte struct.  This routine picks
1991 /// the best LLVM IR type to represent this, which may be i64 or may be anything
1992 /// else that the backend will pass in a GPR that works better (e.g. i8, %foo*,
1993 /// etc).
1994 ///
1995 /// PrefType is an LLVM IR type that corresponds to (part of) the IR type for
1996 /// the source type.  IROffset is an offset in bytes into the LLVM IR type that
1997 /// the 8-byte value references.  PrefType may be null.
1998 ///
1999 /// SourceTy is the source level type for the entire argument.  SourceOffset is
2000 /// an offset into this that we're processing (which is always either 0 or 8).
2001 ///
2002 llvm::Type *X86_64ABIInfo::
2003 GetINTEGERTypeAtOffset(llvm::Type *IRType, unsigned IROffset,
2004                        QualType SourceTy, unsigned SourceOffset) const {
2005   // If we're dealing with an un-offset LLVM IR type, then it means that we're
2006   // returning an 8-byte unit starting with it.  See if we can safely use it.
2007   if (IROffset == 0) {
2008     // Pointers and int64's always fill the 8-byte unit.
2009     if ((isa<llvm::PointerType>(IRType) && Has64BitPointers) ||
2010         IRType->isIntegerTy(64))
2011       return IRType;
2012 
2013     // If we have a 1/2/4-byte integer, we can use it only if the rest of the
2014     // goodness in the source type is just tail padding.  This is allowed to
2015     // kick in for struct {double,int} on the int, but not on
2016     // struct{double,int,int} because we wouldn't return the second int.  We
2017     // have to do this analysis on the source type because we can't depend on
2018     // unions being lowered a specific way etc.
2019     if (IRType->isIntegerTy(8) || IRType->isIntegerTy(16) ||
2020         IRType->isIntegerTy(32) ||
2021         (isa<llvm::PointerType>(IRType) && !Has64BitPointers)) {
2022       unsigned BitWidth = isa<llvm::PointerType>(IRType) ? 32 :
2023           cast<llvm::IntegerType>(IRType)->getBitWidth();
2024 
2025       if (BitsContainNoUserData(SourceTy, SourceOffset*8+BitWidth,
2026                                 SourceOffset*8+64, getContext()))
2027         return IRType;
2028     }
2029   }
2030 
2031   if (llvm::StructType *STy = dyn_cast<llvm::StructType>(IRType)) {
2032     // If this is a struct, recurse into the field at the specified offset.
2033     const llvm::StructLayout *SL = getDataLayout().getStructLayout(STy);
2034     if (IROffset < SL->getSizeInBytes()) {
2035       unsigned FieldIdx = SL->getElementContainingOffset(IROffset);
2036       IROffset -= SL->getElementOffset(FieldIdx);
2037 
2038       return GetINTEGERTypeAtOffset(STy->getElementType(FieldIdx), IROffset,
2039                                     SourceTy, SourceOffset);
2040     }
2041   }
2042 
2043   if (llvm::ArrayType *ATy = dyn_cast<llvm::ArrayType>(IRType)) {
2044     llvm::Type *EltTy = ATy->getElementType();
2045     unsigned EltSize = getDataLayout().getTypeAllocSize(EltTy);
2046     unsigned EltOffset = IROffset/EltSize*EltSize;
2047     return GetINTEGERTypeAtOffset(EltTy, IROffset-EltOffset, SourceTy,
2048                                   SourceOffset);
2049   }
2050 
2051   // Okay, we don't have any better idea of what to pass, so we pass this in an
2052   // integer register that isn't too big to fit the rest of the struct.
2053   unsigned TySizeInBytes =
2054     (unsigned)getContext().getTypeSizeInChars(SourceTy).getQuantity();
2055 
2056   assert(TySizeInBytes != SourceOffset && "Empty field?");
2057 
2058   // It is always safe to classify this as an integer type up to i64 that
2059   // isn't larger than the structure.
2060   return llvm::IntegerType::get(getVMContext(),
2061                                 std::min(TySizeInBytes-SourceOffset, 8U)*8);
2062 }
2063 
2064 
2065 /// GetX86_64ByValArgumentPair - Given a high and low type that can ideally
2066 /// be used as elements of a two register pair to pass or return, return a
2067 /// first class aggregate to represent them.  For example, if the low part of
2068 /// a by-value argument should be passed as i32* and the high part as float,
2069 /// return {i32*, float}.
2070 static llvm::Type *
2071 GetX86_64ByValArgumentPair(llvm::Type *Lo, llvm::Type *Hi,
2072                            const llvm::DataLayout &TD) {
2073   // In order to correctly satisfy the ABI, we need to the high part to start
2074   // at offset 8.  If the high and low parts we inferred are both 4-byte types
2075   // (e.g. i32 and i32) then the resultant struct type ({i32,i32}) won't have
2076   // the second element at offset 8.  Check for this:
2077   unsigned LoSize = (unsigned)TD.getTypeAllocSize(Lo);
2078   unsigned HiAlign = TD.getABITypeAlignment(Hi);
2079   unsigned HiStart = llvm::DataLayout::RoundUpAlignment(LoSize, HiAlign);
2080   assert(HiStart != 0 && HiStart <= 8 && "Invalid x86-64 argument pair!");
2081 
2082   // To handle this, we have to increase the size of the low part so that the
2083   // second element will start at an 8 byte offset.  We can't increase the size
2084   // of the second element because it might make us access off the end of the
2085   // struct.
2086   if (HiStart != 8) {
2087     // There are only two sorts of types the ABI generation code can produce for
2088     // the low part of a pair that aren't 8 bytes in size: float or i8/i16/i32.
2089     // Promote these to a larger type.
2090     if (Lo->isFloatTy())
2091       Lo = llvm::Type::getDoubleTy(Lo->getContext());
2092     else {
2093       assert(Lo->isIntegerTy() && "Invalid/unknown lo type");
2094       Lo = llvm::Type::getInt64Ty(Lo->getContext());
2095     }
2096   }
2097 
2098   llvm::StructType *Result = llvm::StructType::get(Lo, Hi, NULL);
2099 
2100 
2101   // Verify that the second element is at an 8-byte offset.
2102   assert(TD.getStructLayout(Result)->getElementOffset(1) == 8 &&
2103          "Invalid x86-64 argument pair!");
2104   return Result;
2105 }
2106 
2107 ABIArgInfo X86_64ABIInfo::
2108 classifyReturnType(QualType RetTy) const {
2109   // AMD64-ABI 3.2.3p4: Rule 1. Classify the return type with the
2110   // classification algorithm.
2111   X86_64ABIInfo::Class Lo, Hi;
2112   classify(RetTy, 0, Lo, Hi, /*isNamedArg*/ true);
2113 
2114   // Check some invariants.
2115   assert((Hi != Memory || Lo == Memory) && "Invalid memory classification.");
2116   assert((Hi != SSEUp || Lo == SSE) && "Invalid SSEUp classification.");
2117 
2118   llvm::Type *ResType = 0;
2119   switch (Lo) {
2120   case NoClass:
2121     if (Hi == NoClass)
2122       return ABIArgInfo::getIgnore();
2123     // If the low part is just padding, it takes no register, leave ResType
2124     // null.
2125     assert((Hi == SSE || Hi == Integer || Hi == X87Up) &&
2126            "Unknown missing lo part");
2127     break;
2128 
2129   case SSEUp:
2130   case X87Up:
2131     llvm_unreachable("Invalid classification for lo word.");
2132 
2133     // AMD64-ABI 3.2.3p4: Rule 2. Types of class memory are returned via
2134     // hidden argument.
2135   case Memory:
2136     return getIndirectReturnResult(RetTy);
2137 
2138     // AMD64-ABI 3.2.3p4: Rule 3. If the class is INTEGER, the next
2139     // available register of the sequence %rax, %rdx is used.
2140   case Integer:
2141     ResType = GetINTEGERTypeAtOffset(CGT.ConvertType(RetTy), 0, RetTy, 0);
2142 
2143     // If we have a sign or zero extended integer, make sure to return Extend
2144     // so that the parameter gets the right LLVM IR attributes.
2145     if (Hi == NoClass && isa<llvm::IntegerType>(ResType)) {
2146       // Treat an enum type as its underlying type.
2147       if (const EnumType *EnumTy = RetTy->getAs<EnumType>())
2148         RetTy = EnumTy->getDecl()->getIntegerType();
2149 
2150       if (RetTy->isIntegralOrEnumerationType() &&
2151           RetTy->isPromotableIntegerType())
2152         return ABIArgInfo::getExtend();
2153     }
2154     break;
2155 
2156     // AMD64-ABI 3.2.3p4: Rule 4. If the class is SSE, the next
2157     // available SSE register of the sequence %xmm0, %xmm1 is used.
2158   case SSE:
2159     ResType = GetSSETypeAtOffset(CGT.ConvertType(RetTy), 0, RetTy, 0);
2160     break;
2161 
2162     // AMD64-ABI 3.2.3p4: Rule 6. If the class is X87, the value is
2163     // returned on the X87 stack in %st0 as 80-bit x87 number.
2164   case X87:
2165     ResType = llvm::Type::getX86_FP80Ty(getVMContext());
2166     break;
2167 
2168     // AMD64-ABI 3.2.3p4: Rule 8. If the class is COMPLEX_X87, the real
2169     // part of the value is returned in %st0 and the imaginary part in
2170     // %st1.
2171   case ComplexX87:
2172     assert(Hi == ComplexX87 && "Unexpected ComplexX87 classification.");
2173     ResType = llvm::StructType::get(llvm::Type::getX86_FP80Ty(getVMContext()),
2174                                     llvm::Type::getX86_FP80Ty(getVMContext()),
2175                                     NULL);
2176     break;
2177   }
2178 
2179   llvm::Type *HighPart = 0;
2180   switch (Hi) {
2181     // Memory was handled previously and X87 should
2182     // never occur as a hi class.
2183   case Memory:
2184   case X87:
2185     llvm_unreachable("Invalid classification for hi word.");
2186 
2187   case ComplexX87: // Previously handled.
2188   case NoClass:
2189     break;
2190 
2191   case Integer:
2192     HighPart = GetINTEGERTypeAtOffset(CGT.ConvertType(RetTy), 8, RetTy, 8);
2193     if (Lo == NoClass)  // Return HighPart at offset 8 in memory.
2194       return ABIArgInfo::getDirect(HighPart, 8);
2195     break;
2196   case SSE:
2197     HighPart = GetSSETypeAtOffset(CGT.ConvertType(RetTy), 8, RetTy, 8);
2198     if (Lo == NoClass)  // Return HighPart at offset 8 in memory.
2199       return ABIArgInfo::getDirect(HighPart, 8);
2200     break;
2201 
2202     // AMD64-ABI 3.2.3p4: Rule 5. If the class is SSEUP, the eightbyte
2203     // is passed in the next available eightbyte chunk if the last used
2204     // vector register.
2205     //
2206     // SSEUP should always be preceded by SSE, just widen.
2207   case SSEUp:
2208     assert(Lo == SSE && "Unexpected SSEUp classification.");
2209     ResType = GetByteVectorType(RetTy);
2210     break;
2211 
2212     // AMD64-ABI 3.2.3p4: Rule 7. If the class is X87UP, the value is
2213     // returned together with the previous X87 value in %st0.
2214   case X87Up:
2215     // If X87Up is preceded by X87, we don't need to do
2216     // anything. However, in some cases with unions it may not be
2217     // preceded by X87. In such situations we follow gcc and pass the
2218     // extra bits in an SSE reg.
2219     if (Lo != X87) {
2220       HighPart = GetSSETypeAtOffset(CGT.ConvertType(RetTy), 8, RetTy, 8);
2221       if (Lo == NoClass)  // Return HighPart at offset 8 in memory.
2222         return ABIArgInfo::getDirect(HighPart, 8);
2223     }
2224     break;
2225   }
2226 
2227   // If a high part was specified, merge it together with the low part.  It is
2228   // known to pass in the high eightbyte of the result.  We do this by forming a
2229   // first class struct aggregate with the high and low part: {low, high}
2230   if (HighPart)
2231     ResType = GetX86_64ByValArgumentPair(ResType, HighPart, getDataLayout());
2232 
2233   return ABIArgInfo::getDirect(ResType);
2234 }
2235 
2236 ABIArgInfo X86_64ABIInfo::classifyArgumentType(
2237   QualType Ty, unsigned freeIntRegs, unsigned &neededInt, unsigned &neededSSE,
2238   bool isNamedArg)
2239   const
2240 {
2241   X86_64ABIInfo::Class Lo, Hi;
2242   classify(Ty, 0, Lo, Hi, isNamedArg);
2243 
2244   // Check some invariants.
2245   // FIXME: Enforce these by construction.
2246   assert((Hi != Memory || Lo == Memory) && "Invalid memory classification.");
2247   assert((Hi != SSEUp || Lo == SSE) && "Invalid SSEUp classification.");
2248 
2249   neededInt = 0;
2250   neededSSE = 0;
2251   llvm::Type *ResType = 0;
2252   switch (Lo) {
2253   case NoClass:
2254     if (Hi == NoClass)
2255       return ABIArgInfo::getIgnore();
2256     // If the low part is just padding, it takes no register, leave ResType
2257     // null.
2258     assert((Hi == SSE || Hi == Integer || Hi == X87Up) &&
2259            "Unknown missing lo part");
2260     break;
2261 
2262     // AMD64-ABI 3.2.3p3: Rule 1. If the class is MEMORY, pass the argument
2263     // on the stack.
2264   case Memory:
2265 
2266     // AMD64-ABI 3.2.3p3: Rule 5. If the class is X87, X87UP or
2267     // COMPLEX_X87, it is passed in memory.
2268   case X87:
2269   case ComplexX87:
2270     if (getRecordArgABI(Ty, getCXXABI()) == CGCXXABI::RAA_Indirect)
2271       ++neededInt;
2272     return getIndirectResult(Ty, freeIntRegs);
2273 
2274   case SSEUp:
2275   case X87Up:
2276     llvm_unreachable("Invalid classification for lo word.");
2277 
2278     // AMD64-ABI 3.2.3p3: Rule 2. If the class is INTEGER, the next
2279     // available register of the sequence %rdi, %rsi, %rdx, %rcx, %r8
2280     // and %r9 is used.
2281   case Integer:
2282     ++neededInt;
2283 
2284     // Pick an 8-byte type based on the preferred type.
2285     ResType = GetINTEGERTypeAtOffset(CGT.ConvertType(Ty), 0, Ty, 0);
2286 
2287     // If we have a sign or zero extended integer, make sure to return Extend
2288     // so that the parameter gets the right LLVM IR attributes.
2289     if (Hi == NoClass && isa<llvm::IntegerType>(ResType)) {
2290       // Treat an enum type as its underlying type.
2291       if (const EnumType *EnumTy = Ty->getAs<EnumType>())
2292         Ty = EnumTy->getDecl()->getIntegerType();
2293 
2294       if (Ty->isIntegralOrEnumerationType() &&
2295           Ty->isPromotableIntegerType())
2296         return ABIArgInfo::getExtend();
2297     }
2298 
2299     break;
2300 
2301     // AMD64-ABI 3.2.3p3: Rule 3. If the class is SSE, the next
2302     // available SSE register is used, the registers are taken in the
2303     // order from %xmm0 to %xmm7.
2304   case SSE: {
2305     llvm::Type *IRType = CGT.ConvertType(Ty);
2306     ResType = GetSSETypeAtOffset(IRType, 0, Ty, 0);
2307     ++neededSSE;
2308     break;
2309   }
2310   }
2311 
2312   llvm::Type *HighPart = 0;
2313   switch (Hi) {
2314     // Memory was handled previously, ComplexX87 and X87 should
2315     // never occur as hi classes, and X87Up must be preceded by X87,
2316     // which is passed in memory.
2317   case Memory:
2318   case X87:
2319   case ComplexX87:
2320     llvm_unreachable("Invalid classification for hi word.");
2321 
2322   case NoClass: break;
2323 
2324   case Integer:
2325     ++neededInt;
2326     // Pick an 8-byte type based on the preferred type.
2327     HighPart = GetINTEGERTypeAtOffset(CGT.ConvertType(Ty), 8, Ty, 8);
2328 
2329     if (Lo == NoClass)  // Pass HighPart at offset 8 in memory.
2330       return ABIArgInfo::getDirect(HighPart, 8);
2331     break;
2332 
2333     // X87Up generally doesn't occur here (long double is passed in
2334     // memory), except in situations involving unions.
2335   case X87Up:
2336   case SSE:
2337     HighPart = GetSSETypeAtOffset(CGT.ConvertType(Ty), 8, Ty, 8);
2338 
2339     if (Lo == NoClass)  // Pass HighPart at offset 8 in memory.
2340       return ABIArgInfo::getDirect(HighPart, 8);
2341 
2342     ++neededSSE;
2343     break;
2344 
2345     // AMD64-ABI 3.2.3p3: Rule 4. If the class is SSEUP, the
2346     // eightbyte is passed in the upper half of the last used SSE
2347     // register.  This only happens when 128-bit vectors are passed.
2348   case SSEUp:
2349     assert(Lo == SSE && "Unexpected SSEUp classification");
2350     ResType = GetByteVectorType(Ty);
2351     break;
2352   }
2353 
2354   // If a high part was specified, merge it together with the low part.  It is
2355   // known to pass in the high eightbyte of the result.  We do this by forming a
2356   // first class struct aggregate with the high and low part: {low, high}
2357   if (HighPart)
2358     ResType = GetX86_64ByValArgumentPair(ResType, HighPart, getDataLayout());
2359 
2360   return ABIArgInfo::getDirect(ResType);
2361 }
2362 
2363 void X86_64ABIInfo::computeInfo(CGFunctionInfo &FI) const {
2364 
2365   FI.getReturnInfo() = classifyReturnType(FI.getReturnType());
2366 
2367   // Keep track of the number of assigned registers.
2368   unsigned freeIntRegs = 6, freeSSERegs = 8;
2369 
2370   // If the return value is indirect, then the hidden argument is consuming one
2371   // integer register.
2372   if (FI.getReturnInfo().isIndirect())
2373     --freeIntRegs;
2374 
2375   bool isVariadic = FI.isVariadic();
2376   unsigned numRequiredArgs = 0;
2377   if (isVariadic)
2378     numRequiredArgs = FI.getRequiredArgs().getNumRequiredArgs();
2379 
2380   // AMD64-ABI 3.2.3p3: Once arguments are classified, the registers
2381   // get assigned (in left-to-right order) for passing as follows...
2382   for (CGFunctionInfo::arg_iterator it = FI.arg_begin(), ie = FI.arg_end();
2383        it != ie; ++it) {
2384     bool isNamedArg = true;
2385     if (isVariadic)
2386       isNamedArg = (it - FI.arg_begin()) <
2387                     static_cast<signed>(numRequiredArgs);
2388 
2389     unsigned neededInt, neededSSE;
2390     it->info = classifyArgumentType(it->type, freeIntRegs, neededInt,
2391                                     neededSSE, isNamedArg);
2392 
2393     // AMD64-ABI 3.2.3p3: If there are no registers available for any
2394     // eightbyte of an argument, the whole argument is passed on the
2395     // stack. If registers have already been assigned for some
2396     // eightbytes of such an argument, the assignments get reverted.
2397     if (freeIntRegs >= neededInt && freeSSERegs >= neededSSE) {
2398       freeIntRegs -= neededInt;
2399       freeSSERegs -= neededSSE;
2400     } else {
2401       it->info = getIndirectResult(it->type, freeIntRegs);
2402     }
2403   }
2404 }
2405 
2406 static llvm::Value *EmitVAArgFromMemory(llvm::Value *VAListAddr,
2407                                         QualType Ty,
2408                                         CodeGenFunction &CGF) {
2409   llvm::Value *overflow_arg_area_p =
2410     CGF.Builder.CreateStructGEP(VAListAddr, 2, "overflow_arg_area_p");
2411   llvm::Value *overflow_arg_area =
2412     CGF.Builder.CreateLoad(overflow_arg_area_p, "overflow_arg_area");
2413 
2414   // AMD64-ABI 3.5.7p5: Step 7. Align l->overflow_arg_area upwards to a 16
2415   // byte boundary if alignment needed by type exceeds 8 byte boundary.
2416   // It isn't stated explicitly in the standard, but in practice we use
2417   // alignment greater than 16 where necessary.
2418   uint64_t Align = CGF.getContext().getTypeAlign(Ty) / 8;
2419   if (Align > 8) {
2420     // overflow_arg_area = (overflow_arg_area + align - 1) & -align;
2421     llvm::Value *Offset =
2422       llvm::ConstantInt::get(CGF.Int64Ty, Align - 1);
2423     overflow_arg_area = CGF.Builder.CreateGEP(overflow_arg_area, Offset);
2424     llvm::Value *AsInt = CGF.Builder.CreatePtrToInt(overflow_arg_area,
2425                                                     CGF.Int64Ty);
2426     llvm::Value *Mask = llvm::ConstantInt::get(CGF.Int64Ty, -(uint64_t)Align);
2427     overflow_arg_area =
2428       CGF.Builder.CreateIntToPtr(CGF.Builder.CreateAnd(AsInt, Mask),
2429                                  overflow_arg_area->getType(),
2430                                  "overflow_arg_area.align");
2431   }
2432 
2433   // AMD64-ABI 3.5.7p5: Step 8. Fetch type from l->overflow_arg_area.
2434   llvm::Type *LTy = CGF.ConvertTypeForMem(Ty);
2435   llvm::Value *Res =
2436     CGF.Builder.CreateBitCast(overflow_arg_area,
2437                               llvm::PointerType::getUnqual(LTy));
2438 
2439   // AMD64-ABI 3.5.7p5: Step 9. Set l->overflow_arg_area to:
2440   // l->overflow_arg_area + sizeof(type).
2441   // AMD64-ABI 3.5.7p5: Step 10. Align l->overflow_arg_area upwards to
2442   // an 8 byte boundary.
2443 
2444   uint64_t SizeInBytes = (CGF.getContext().getTypeSize(Ty) + 7) / 8;
2445   llvm::Value *Offset =
2446       llvm::ConstantInt::get(CGF.Int32Ty, (SizeInBytes + 7)  & ~7);
2447   overflow_arg_area = CGF.Builder.CreateGEP(overflow_arg_area, Offset,
2448                                             "overflow_arg_area.next");
2449   CGF.Builder.CreateStore(overflow_arg_area, overflow_arg_area_p);
2450 
2451   // AMD64-ABI 3.5.7p5: Step 11. Return the fetched type.
2452   return Res;
2453 }
2454 
2455 llvm::Value *X86_64ABIInfo::EmitVAArg(llvm::Value *VAListAddr, QualType Ty,
2456                                       CodeGenFunction &CGF) const {
2457   // Assume that va_list type is correct; should be pointer to LLVM type:
2458   // struct {
2459   //   i32 gp_offset;
2460   //   i32 fp_offset;
2461   //   i8* overflow_arg_area;
2462   //   i8* reg_save_area;
2463   // };
2464   unsigned neededInt, neededSSE;
2465 
2466   Ty = CGF.getContext().getCanonicalType(Ty);
2467   ABIArgInfo AI = classifyArgumentType(Ty, 0, neededInt, neededSSE,
2468                                        /*isNamedArg*/false);
2469 
2470   // AMD64-ABI 3.5.7p5: Step 1. Determine whether type may be passed
2471   // in the registers. If not go to step 7.
2472   if (!neededInt && !neededSSE)
2473     return EmitVAArgFromMemory(VAListAddr, Ty, CGF);
2474 
2475   // AMD64-ABI 3.5.7p5: Step 2. Compute num_gp to hold the number of
2476   // general purpose registers needed to pass type and num_fp to hold
2477   // the number of floating point registers needed.
2478 
2479   // AMD64-ABI 3.5.7p5: Step 3. Verify whether arguments fit into
2480   // registers. In the case: l->gp_offset > 48 - num_gp * 8 or
2481   // l->fp_offset > 304 - num_fp * 16 go to step 7.
2482   //
2483   // NOTE: 304 is a typo, there are (6 * 8 + 8 * 16) = 176 bytes of
2484   // register save space).
2485 
2486   llvm::Value *InRegs = 0;
2487   llvm::Value *gp_offset_p = 0, *gp_offset = 0;
2488   llvm::Value *fp_offset_p = 0, *fp_offset = 0;
2489   if (neededInt) {
2490     gp_offset_p = CGF.Builder.CreateStructGEP(VAListAddr, 0, "gp_offset_p");
2491     gp_offset = CGF.Builder.CreateLoad(gp_offset_p, "gp_offset");
2492     InRegs = llvm::ConstantInt::get(CGF.Int32Ty, 48 - neededInt * 8);
2493     InRegs = CGF.Builder.CreateICmpULE(gp_offset, InRegs, "fits_in_gp");
2494   }
2495 
2496   if (neededSSE) {
2497     fp_offset_p = CGF.Builder.CreateStructGEP(VAListAddr, 1, "fp_offset_p");
2498     fp_offset = CGF.Builder.CreateLoad(fp_offset_p, "fp_offset");
2499     llvm::Value *FitsInFP =
2500       llvm::ConstantInt::get(CGF.Int32Ty, 176 - neededSSE * 16);
2501     FitsInFP = CGF.Builder.CreateICmpULE(fp_offset, FitsInFP, "fits_in_fp");
2502     InRegs = InRegs ? CGF.Builder.CreateAnd(InRegs, FitsInFP) : FitsInFP;
2503   }
2504 
2505   llvm::BasicBlock *InRegBlock = CGF.createBasicBlock("vaarg.in_reg");
2506   llvm::BasicBlock *InMemBlock = CGF.createBasicBlock("vaarg.in_mem");
2507   llvm::BasicBlock *ContBlock = CGF.createBasicBlock("vaarg.end");
2508   CGF.Builder.CreateCondBr(InRegs, InRegBlock, InMemBlock);
2509 
2510   // Emit code to load the value if it was passed in registers.
2511 
2512   CGF.EmitBlock(InRegBlock);
2513 
2514   // AMD64-ABI 3.5.7p5: Step 4. Fetch type from l->reg_save_area with
2515   // an offset of l->gp_offset and/or l->fp_offset. This may require
2516   // copying to a temporary location in case the parameter is passed
2517   // in different register classes or requires an alignment greater
2518   // than 8 for general purpose registers and 16 for XMM registers.
2519   //
2520   // FIXME: This really results in shameful code when we end up needing to
2521   // collect arguments from different places; often what should result in a
2522   // simple assembling of a structure from scattered addresses has many more
2523   // loads than necessary. Can we clean this up?
2524   llvm::Type *LTy = CGF.ConvertTypeForMem(Ty);
2525   llvm::Value *RegAddr =
2526     CGF.Builder.CreateLoad(CGF.Builder.CreateStructGEP(VAListAddr, 3),
2527                            "reg_save_area");
2528   if (neededInt && neededSSE) {
2529     // FIXME: Cleanup.
2530     assert(AI.isDirect() && "Unexpected ABI info for mixed regs");
2531     llvm::StructType *ST = cast<llvm::StructType>(AI.getCoerceToType());
2532     llvm::Value *Tmp = CGF.CreateMemTemp(Ty);
2533     Tmp = CGF.Builder.CreateBitCast(Tmp, ST->getPointerTo());
2534     assert(ST->getNumElements() == 2 && "Unexpected ABI info for mixed regs");
2535     llvm::Type *TyLo = ST->getElementType(0);
2536     llvm::Type *TyHi = ST->getElementType(1);
2537     assert((TyLo->isFPOrFPVectorTy() ^ TyHi->isFPOrFPVectorTy()) &&
2538            "Unexpected ABI info for mixed regs");
2539     llvm::Type *PTyLo = llvm::PointerType::getUnqual(TyLo);
2540     llvm::Type *PTyHi = llvm::PointerType::getUnqual(TyHi);
2541     llvm::Value *GPAddr = CGF.Builder.CreateGEP(RegAddr, gp_offset);
2542     llvm::Value *FPAddr = CGF.Builder.CreateGEP(RegAddr, fp_offset);
2543     llvm::Value *RegLoAddr = TyLo->isFloatingPointTy() ? FPAddr : GPAddr;
2544     llvm::Value *RegHiAddr = TyLo->isFloatingPointTy() ? GPAddr : FPAddr;
2545     llvm::Value *V =
2546       CGF.Builder.CreateLoad(CGF.Builder.CreateBitCast(RegLoAddr, PTyLo));
2547     CGF.Builder.CreateStore(V, CGF.Builder.CreateStructGEP(Tmp, 0));
2548     V = CGF.Builder.CreateLoad(CGF.Builder.CreateBitCast(RegHiAddr, PTyHi));
2549     CGF.Builder.CreateStore(V, CGF.Builder.CreateStructGEP(Tmp, 1));
2550 
2551     RegAddr = CGF.Builder.CreateBitCast(Tmp,
2552                                         llvm::PointerType::getUnqual(LTy));
2553   } else if (neededInt) {
2554     RegAddr = CGF.Builder.CreateGEP(RegAddr, gp_offset);
2555     RegAddr = CGF.Builder.CreateBitCast(RegAddr,
2556                                         llvm::PointerType::getUnqual(LTy));
2557 
2558     // Copy to a temporary if necessary to ensure the appropriate alignment.
2559     std::pair<CharUnits, CharUnits> SizeAlign =
2560         CGF.getContext().getTypeInfoInChars(Ty);
2561     uint64_t TySize = SizeAlign.first.getQuantity();
2562     unsigned TyAlign = SizeAlign.second.getQuantity();
2563     if (TyAlign > 8) {
2564       llvm::Value *Tmp = CGF.CreateMemTemp(Ty);
2565       CGF.Builder.CreateMemCpy(Tmp, RegAddr, TySize, 8, false);
2566       RegAddr = Tmp;
2567     }
2568   } else if (neededSSE == 1) {
2569     RegAddr = CGF.Builder.CreateGEP(RegAddr, fp_offset);
2570     RegAddr = CGF.Builder.CreateBitCast(RegAddr,
2571                                         llvm::PointerType::getUnqual(LTy));
2572   } else {
2573     assert(neededSSE == 2 && "Invalid number of needed registers!");
2574     // SSE registers are spaced 16 bytes apart in the register save
2575     // area, we need to collect the two eightbytes together.
2576     llvm::Value *RegAddrLo = CGF.Builder.CreateGEP(RegAddr, fp_offset);
2577     llvm::Value *RegAddrHi = CGF.Builder.CreateConstGEP1_32(RegAddrLo, 16);
2578     llvm::Type *DoubleTy = CGF.DoubleTy;
2579     llvm::Type *DblPtrTy =
2580       llvm::PointerType::getUnqual(DoubleTy);
2581     llvm::StructType *ST = llvm::StructType::get(DoubleTy, DoubleTy, NULL);
2582     llvm::Value *V, *Tmp = CGF.CreateMemTemp(Ty);
2583     Tmp = CGF.Builder.CreateBitCast(Tmp, ST->getPointerTo());
2584     V = CGF.Builder.CreateLoad(CGF.Builder.CreateBitCast(RegAddrLo,
2585                                                          DblPtrTy));
2586     CGF.Builder.CreateStore(V, CGF.Builder.CreateStructGEP(Tmp, 0));
2587     V = CGF.Builder.CreateLoad(CGF.Builder.CreateBitCast(RegAddrHi,
2588                                                          DblPtrTy));
2589     CGF.Builder.CreateStore(V, CGF.Builder.CreateStructGEP(Tmp, 1));
2590     RegAddr = CGF.Builder.CreateBitCast(Tmp,
2591                                         llvm::PointerType::getUnqual(LTy));
2592   }
2593 
2594   // AMD64-ABI 3.5.7p5: Step 5. Set:
2595   // l->gp_offset = l->gp_offset + num_gp * 8
2596   // l->fp_offset = l->fp_offset + num_fp * 16.
2597   if (neededInt) {
2598     llvm::Value *Offset = llvm::ConstantInt::get(CGF.Int32Ty, neededInt * 8);
2599     CGF.Builder.CreateStore(CGF.Builder.CreateAdd(gp_offset, Offset),
2600                             gp_offset_p);
2601   }
2602   if (neededSSE) {
2603     llvm::Value *Offset = llvm::ConstantInt::get(CGF.Int32Ty, neededSSE * 16);
2604     CGF.Builder.CreateStore(CGF.Builder.CreateAdd(fp_offset, Offset),
2605                             fp_offset_p);
2606   }
2607   CGF.EmitBranch(ContBlock);
2608 
2609   // Emit code to load the value if it was passed in memory.
2610 
2611   CGF.EmitBlock(InMemBlock);
2612   llvm::Value *MemAddr = EmitVAArgFromMemory(VAListAddr, Ty, CGF);
2613 
2614   // Return the appropriate result.
2615 
2616   CGF.EmitBlock(ContBlock);
2617   llvm::PHINode *ResAddr = CGF.Builder.CreatePHI(RegAddr->getType(), 2,
2618                                                  "vaarg.addr");
2619   ResAddr->addIncoming(RegAddr, InRegBlock);
2620   ResAddr->addIncoming(MemAddr, InMemBlock);
2621   return ResAddr;
2622 }
2623 
2624 ABIArgInfo WinX86_64ABIInfo::classify(QualType Ty, bool IsReturnType) const {
2625 
2626   if (Ty->isVoidType())
2627     return ABIArgInfo::getIgnore();
2628 
2629   if (const EnumType *EnumTy = Ty->getAs<EnumType>())
2630     Ty = EnumTy->getDecl()->getIntegerType();
2631 
2632   uint64_t Size = getContext().getTypeSize(Ty);
2633 
2634   if (const RecordType *RT = Ty->getAs<RecordType>()) {
2635     if (IsReturnType) {
2636       if (isRecordReturnIndirect(RT, getCXXABI()))
2637         return ABIArgInfo::getIndirect(0, false);
2638     } else {
2639       if (CGCXXABI::RecordArgABI RAA = getRecordArgABI(RT, getCXXABI()))
2640         return ABIArgInfo::getIndirect(0, RAA == CGCXXABI::RAA_DirectInMemory);
2641     }
2642 
2643     if (RT->getDecl()->hasFlexibleArrayMember())
2644       return ABIArgInfo::getIndirect(0, /*ByVal=*/false);
2645 
2646     // FIXME: mingw-w64-gcc emits 128-bit struct as i128
2647     if (Size == 128 && getTarget().getTriple().getOS() == llvm::Triple::MinGW32)
2648       return ABIArgInfo::getDirect(llvm::IntegerType::get(getVMContext(),
2649                                                           Size));
2650 
2651     // MS x64 ABI requirement: "Any argument that doesn't fit in 8 bytes, or is
2652     // not 1, 2, 4, or 8 bytes, must be passed by reference."
2653     if (Size <= 64 &&
2654         (Size & (Size - 1)) == 0)
2655       return ABIArgInfo::getDirect(llvm::IntegerType::get(getVMContext(),
2656                                                           Size));
2657 
2658     return ABIArgInfo::getIndirect(0, /*ByVal=*/false);
2659   }
2660 
2661   if (Ty->isPromotableIntegerType())
2662     return ABIArgInfo::getExtend();
2663 
2664   return ABIArgInfo::getDirect();
2665 }
2666 
2667 void WinX86_64ABIInfo::computeInfo(CGFunctionInfo &FI) const {
2668 
2669   QualType RetTy = FI.getReturnType();
2670   FI.getReturnInfo() = classify(RetTy, true);
2671 
2672   for (CGFunctionInfo::arg_iterator it = FI.arg_begin(), ie = FI.arg_end();
2673        it != ie; ++it)
2674     it->info = classify(it->type, false);
2675 }
2676 
2677 llvm::Value *WinX86_64ABIInfo::EmitVAArg(llvm::Value *VAListAddr, QualType Ty,
2678                                       CodeGenFunction &CGF) const {
2679   llvm::Type *BPP = CGF.Int8PtrPtrTy;
2680 
2681   CGBuilderTy &Builder = CGF.Builder;
2682   llvm::Value *VAListAddrAsBPP = Builder.CreateBitCast(VAListAddr, BPP,
2683                                                        "ap");
2684   llvm::Value *Addr = Builder.CreateLoad(VAListAddrAsBPP, "ap.cur");
2685   llvm::Type *PTy =
2686     llvm::PointerType::getUnqual(CGF.ConvertType(Ty));
2687   llvm::Value *AddrTyped = Builder.CreateBitCast(Addr, PTy);
2688 
2689   uint64_t Offset =
2690     llvm::RoundUpToAlignment(CGF.getContext().getTypeSize(Ty) / 8, 8);
2691   llvm::Value *NextAddr =
2692     Builder.CreateGEP(Addr, llvm::ConstantInt::get(CGF.Int32Ty, Offset),
2693                       "ap.next");
2694   Builder.CreateStore(NextAddr, VAListAddrAsBPP);
2695 
2696   return AddrTyped;
2697 }
2698 
2699 namespace {
2700 
2701 class NaClX86_64ABIInfo : public ABIInfo {
2702  public:
2703   NaClX86_64ABIInfo(CodeGen::CodeGenTypes &CGT, bool HasAVX)
2704       : ABIInfo(CGT), PInfo(CGT), NInfo(CGT, HasAVX) {}
2705   virtual void computeInfo(CGFunctionInfo &FI) const;
2706   virtual llvm::Value *EmitVAArg(llvm::Value *VAListAddr, QualType Ty,
2707                                  CodeGenFunction &CGF) const;
2708  private:
2709   PNaClABIInfo PInfo;  // Used for generating calls with pnaclcall callingconv.
2710   X86_64ABIInfo NInfo; // Used for everything else.
2711 };
2712 
2713 class NaClX86_64TargetCodeGenInfo : public TargetCodeGenInfo  {
2714  public:
2715   NaClX86_64TargetCodeGenInfo(CodeGen::CodeGenTypes &CGT, bool HasAVX)
2716       : TargetCodeGenInfo(new NaClX86_64ABIInfo(CGT, HasAVX)) {}
2717 };
2718 
2719 }
2720 
2721 void NaClX86_64ABIInfo::computeInfo(CGFunctionInfo &FI) const {
2722   if (FI.getASTCallingConvention() == CC_PnaclCall)
2723     PInfo.computeInfo(FI);
2724   else
2725     NInfo.computeInfo(FI);
2726 }
2727 
2728 llvm::Value *NaClX86_64ABIInfo::EmitVAArg(llvm::Value *VAListAddr, QualType Ty,
2729                                           CodeGenFunction &CGF) const {
2730   // Always use the native convention; calling pnacl-style varargs functions
2731   // is unuspported.
2732   return NInfo.EmitVAArg(VAListAddr, Ty, CGF);
2733 }
2734 
2735 
2736 // PowerPC-32
2737 
2738 namespace {
2739 class PPC32TargetCodeGenInfo : public DefaultTargetCodeGenInfo {
2740 public:
2741   PPC32TargetCodeGenInfo(CodeGenTypes &CGT) : DefaultTargetCodeGenInfo(CGT) {}
2742 
2743   int getDwarfEHStackPointer(CodeGen::CodeGenModule &M) const {
2744     // This is recovered from gcc output.
2745     return 1; // r1 is the dedicated stack pointer
2746   }
2747 
2748   bool initDwarfEHRegSizeTable(CodeGen::CodeGenFunction &CGF,
2749                                llvm::Value *Address) const;
2750 };
2751 
2752 }
2753 
2754 bool
2755 PPC32TargetCodeGenInfo::initDwarfEHRegSizeTable(CodeGen::CodeGenFunction &CGF,
2756                                                 llvm::Value *Address) const {
2757   // This is calculated from the LLVM and GCC tables and verified
2758   // against gcc output.  AFAIK all ABIs use the same encoding.
2759 
2760   CodeGen::CGBuilderTy &Builder = CGF.Builder;
2761 
2762   llvm::IntegerType *i8 = CGF.Int8Ty;
2763   llvm::Value *Four8 = llvm::ConstantInt::get(i8, 4);
2764   llvm::Value *Eight8 = llvm::ConstantInt::get(i8, 8);
2765   llvm::Value *Sixteen8 = llvm::ConstantInt::get(i8, 16);
2766 
2767   // 0-31: r0-31, the 4-byte general-purpose registers
2768   AssignToArrayRange(Builder, Address, Four8, 0, 31);
2769 
2770   // 32-63: fp0-31, the 8-byte floating-point registers
2771   AssignToArrayRange(Builder, Address, Eight8, 32, 63);
2772 
2773   // 64-76 are various 4-byte special-purpose registers:
2774   // 64: mq
2775   // 65: lr
2776   // 66: ctr
2777   // 67: ap
2778   // 68-75 cr0-7
2779   // 76: xer
2780   AssignToArrayRange(Builder, Address, Four8, 64, 76);
2781 
2782   // 77-108: v0-31, the 16-byte vector registers
2783   AssignToArrayRange(Builder, Address, Sixteen8, 77, 108);
2784 
2785   // 109: vrsave
2786   // 110: vscr
2787   // 111: spe_acc
2788   // 112: spefscr
2789   // 113: sfp
2790   AssignToArrayRange(Builder, Address, Four8, 109, 113);
2791 
2792   return false;
2793 }
2794 
2795 // PowerPC-64
2796 
2797 namespace {
2798 /// PPC64_SVR4_ABIInfo - The 64-bit PowerPC ELF (SVR4) ABI information.
2799 class PPC64_SVR4_ABIInfo : public DefaultABIInfo {
2800 
2801 public:
2802   PPC64_SVR4_ABIInfo(CodeGen::CodeGenTypes &CGT) : DefaultABIInfo(CGT) {}
2803 
2804   bool isPromotableTypeForABI(QualType Ty) const;
2805 
2806   ABIArgInfo classifyReturnType(QualType RetTy) const;
2807   ABIArgInfo classifyArgumentType(QualType Ty) const;
2808 
2809   // TODO: We can add more logic to computeInfo to improve performance.
2810   // Example: For aggregate arguments that fit in a register, we could
2811   // use getDirectInReg (as is done below for structs containing a single
2812   // floating-point value) to avoid pushing them to memory on function
2813   // entry.  This would require changing the logic in PPCISelLowering
2814   // when lowering the parameters in the caller and args in the callee.
2815   virtual void computeInfo(CGFunctionInfo &FI) const {
2816     FI.getReturnInfo() = classifyReturnType(FI.getReturnType());
2817     for (CGFunctionInfo::arg_iterator it = FI.arg_begin(), ie = FI.arg_end();
2818          it != ie; ++it) {
2819       // We rely on the default argument classification for the most part.
2820       // One exception:  An aggregate containing a single floating-point
2821       // or vector item must be passed in a register if one is available.
2822       const Type *T = isSingleElementStruct(it->type, getContext());
2823       if (T) {
2824         const BuiltinType *BT = T->getAs<BuiltinType>();
2825         if (T->isVectorType() || (BT && BT->isFloatingPoint())) {
2826           QualType QT(T, 0);
2827           it->info = ABIArgInfo::getDirectInReg(CGT.ConvertType(QT));
2828           continue;
2829         }
2830       }
2831       it->info = classifyArgumentType(it->type);
2832     }
2833   }
2834 
2835   virtual llvm::Value *EmitVAArg(llvm::Value *VAListAddr,
2836                                  QualType Ty,
2837                                  CodeGenFunction &CGF) const;
2838 };
2839 
2840 class PPC64_SVR4_TargetCodeGenInfo : public TargetCodeGenInfo {
2841 public:
2842   PPC64_SVR4_TargetCodeGenInfo(CodeGenTypes &CGT)
2843     : TargetCodeGenInfo(new PPC64_SVR4_ABIInfo(CGT)) {}
2844 
2845   int getDwarfEHStackPointer(CodeGen::CodeGenModule &M) const {
2846     // This is recovered from gcc output.
2847     return 1; // r1 is the dedicated stack pointer
2848   }
2849 
2850   bool initDwarfEHRegSizeTable(CodeGen::CodeGenFunction &CGF,
2851                                llvm::Value *Address) const;
2852 };
2853 
2854 class PPC64TargetCodeGenInfo : public DefaultTargetCodeGenInfo {
2855 public:
2856   PPC64TargetCodeGenInfo(CodeGenTypes &CGT) : DefaultTargetCodeGenInfo(CGT) {}
2857 
2858   int getDwarfEHStackPointer(CodeGen::CodeGenModule &M) const {
2859     // This is recovered from gcc output.
2860     return 1; // r1 is the dedicated stack pointer
2861   }
2862 
2863   bool initDwarfEHRegSizeTable(CodeGen::CodeGenFunction &CGF,
2864                                llvm::Value *Address) const;
2865 };
2866 
2867 }
2868 
2869 // Return true if the ABI requires Ty to be passed sign- or zero-
2870 // extended to 64 bits.
2871 bool
2872 PPC64_SVR4_ABIInfo::isPromotableTypeForABI(QualType Ty) const {
2873   // Treat an enum type as its underlying type.
2874   if (const EnumType *EnumTy = Ty->getAs<EnumType>())
2875     Ty = EnumTy->getDecl()->getIntegerType();
2876 
2877   // Promotable integer types are required to be promoted by the ABI.
2878   if (Ty->isPromotableIntegerType())
2879     return true;
2880 
2881   // In addition to the usual promotable integer types, we also need to
2882   // extend all 32-bit types, since the ABI requires promotion to 64 bits.
2883   if (const BuiltinType *BT = Ty->getAs<BuiltinType>())
2884     switch (BT->getKind()) {
2885     case BuiltinType::Int:
2886     case BuiltinType::UInt:
2887       return true;
2888     default:
2889       break;
2890     }
2891 
2892   return false;
2893 }
2894 
2895 ABIArgInfo
2896 PPC64_SVR4_ABIInfo::classifyArgumentType(QualType Ty) const {
2897   if (Ty->isAnyComplexType())
2898     return ABIArgInfo::getDirect();
2899 
2900   if (isAggregateTypeForABI(Ty)) {
2901     if (CGCXXABI::RecordArgABI RAA = getRecordArgABI(Ty, getCXXABI()))
2902       return ABIArgInfo::getIndirect(0, RAA == CGCXXABI::RAA_DirectInMemory);
2903 
2904     return ABIArgInfo::getIndirect(0);
2905   }
2906 
2907   return (isPromotableTypeForABI(Ty) ?
2908           ABIArgInfo::getExtend() : ABIArgInfo::getDirect());
2909 }
2910 
2911 ABIArgInfo
2912 PPC64_SVR4_ABIInfo::classifyReturnType(QualType RetTy) const {
2913   if (RetTy->isVoidType())
2914     return ABIArgInfo::getIgnore();
2915 
2916   if (RetTy->isAnyComplexType())
2917     return ABIArgInfo::getDirect();
2918 
2919   if (isAggregateTypeForABI(RetTy))
2920     return ABIArgInfo::getIndirect(0);
2921 
2922   return (isPromotableTypeForABI(RetTy) ?
2923           ABIArgInfo::getExtend() : ABIArgInfo::getDirect());
2924 }
2925 
2926 // Based on ARMABIInfo::EmitVAArg, adjusted for 64-bit machine.
2927 llvm::Value *PPC64_SVR4_ABIInfo::EmitVAArg(llvm::Value *VAListAddr,
2928                                            QualType Ty,
2929                                            CodeGenFunction &CGF) const {
2930   llvm::Type *BP = CGF.Int8PtrTy;
2931   llvm::Type *BPP = CGF.Int8PtrPtrTy;
2932 
2933   CGBuilderTy &Builder = CGF.Builder;
2934   llvm::Value *VAListAddrAsBPP = Builder.CreateBitCast(VAListAddr, BPP, "ap");
2935   llvm::Value *Addr = Builder.CreateLoad(VAListAddrAsBPP, "ap.cur");
2936 
2937   // Update the va_list pointer.  The pointer should be bumped by the
2938   // size of the object.  We can trust getTypeSize() except for a complex
2939   // type whose base type is smaller than a doubleword.  For these, the
2940   // size of the object is 16 bytes; see below for further explanation.
2941   unsigned SizeInBytes = CGF.getContext().getTypeSize(Ty) / 8;
2942   QualType BaseTy;
2943   unsigned CplxBaseSize = 0;
2944 
2945   if (const ComplexType *CTy = Ty->getAs<ComplexType>()) {
2946     BaseTy = CTy->getElementType();
2947     CplxBaseSize = CGF.getContext().getTypeSize(BaseTy) / 8;
2948     if (CplxBaseSize < 8)
2949       SizeInBytes = 16;
2950   }
2951 
2952   unsigned Offset = llvm::RoundUpToAlignment(SizeInBytes, 8);
2953   llvm::Value *NextAddr =
2954     Builder.CreateGEP(Addr, llvm::ConstantInt::get(CGF.Int64Ty, Offset),
2955                       "ap.next");
2956   Builder.CreateStore(NextAddr, VAListAddrAsBPP);
2957 
2958   // If we have a complex type and the base type is smaller than 8 bytes,
2959   // the ABI calls for the real and imaginary parts to be right-adjusted
2960   // in separate doublewords.  However, Clang expects us to produce a
2961   // pointer to a structure with the two parts packed tightly.  So generate
2962   // loads of the real and imaginary parts relative to the va_list pointer,
2963   // and store them to a temporary structure.
2964   if (CplxBaseSize && CplxBaseSize < 8) {
2965     llvm::Value *RealAddr = Builder.CreatePtrToInt(Addr, CGF.Int64Ty);
2966     llvm::Value *ImagAddr = RealAddr;
2967     RealAddr = Builder.CreateAdd(RealAddr, Builder.getInt64(8 - CplxBaseSize));
2968     ImagAddr = Builder.CreateAdd(ImagAddr, Builder.getInt64(16 - CplxBaseSize));
2969     llvm::Type *PBaseTy = llvm::PointerType::getUnqual(CGF.ConvertType(BaseTy));
2970     RealAddr = Builder.CreateIntToPtr(RealAddr, PBaseTy);
2971     ImagAddr = Builder.CreateIntToPtr(ImagAddr, PBaseTy);
2972     llvm::Value *Real = Builder.CreateLoad(RealAddr, false, ".vareal");
2973     llvm::Value *Imag = Builder.CreateLoad(ImagAddr, false, ".vaimag");
2974     llvm::Value *Ptr = CGF.CreateTempAlloca(CGT.ConvertTypeForMem(Ty),
2975                                             "vacplx");
2976     llvm::Value *RealPtr = Builder.CreateStructGEP(Ptr, 0, ".real");
2977     llvm::Value *ImagPtr = Builder.CreateStructGEP(Ptr, 1, ".imag");
2978     Builder.CreateStore(Real, RealPtr, false);
2979     Builder.CreateStore(Imag, ImagPtr, false);
2980     return Ptr;
2981   }
2982 
2983   // If the argument is smaller than 8 bytes, it is right-adjusted in
2984   // its doubleword slot.  Adjust the pointer to pick it up from the
2985   // correct offset.
2986   if (SizeInBytes < 8) {
2987     llvm::Value *AddrAsInt = Builder.CreatePtrToInt(Addr, CGF.Int64Ty);
2988     AddrAsInt = Builder.CreateAdd(AddrAsInt, Builder.getInt64(8 - SizeInBytes));
2989     Addr = Builder.CreateIntToPtr(AddrAsInt, BP);
2990   }
2991 
2992   llvm::Type *PTy = llvm::PointerType::getUnqual(CGF.ConvertType(Ty));
2993   return Builder.CreateBitCast(Addr, PTy);
2994 }
2995 
2996 static bool
2997 PPC64_initDwarfEHRegSizeTable(CodeGen::CodeGenFunction &CGF,
2998                               llvm::Value *Address) {
2999   // This is calculated from the LLVM and GCC tables and verified
3000   // against gcc output.  AFAIK all ABIs use the same encoding.
3001 
3002   CodeGen::CGBuilderTy &Builder = CGF.Builder;
3003 
3004   llvm::IntegerType *i8 = CGF.Int8Ty;
3005   llvm::Value *Four8 = llvm::ConstantInt::get(i8, 4);
3006   llvm::Value *Eight8 = llvm::ConstantInt::get(i8, 8);
3007   llvm::Value *Sixteen8 = llvm::ConstantInt::get(i8, 16);
3008 
3009   // 0-31: r0-31, the 8-byte general-purpose registers
3010   AssignToArrayRange(Builder, Address, Eight8, 0, 31);
3011 
3012   // 32-63: fp0-31, the 8-byte floating-point registers
3013   AssignToArrayRange(Builder, Address, Eight8, 32, 63);
3014 
3015   // 64-76 are various 4-byte special-purpose registers:
3016   // 64: mq
3017   // 65: lr
3018   // 66: ctr
3019   // 67: ap
3020   // 68-75 cr0-7
3021   // 76: xer
3022   AssignToArrayRange(Builder, Address, Four8, 64, 76);
3023 
3024   // 77-108: v0-31, the 16-byte vector registers
3025   AssignToArrayRange(Builder, Address, Sixteen8, 77, 108);
3026 
3027   // 109: vrsave
3028   // 110: vscr
3029   // 111: spe_acc
3030   // 112: spefscr
3031   // 113: sfp
3032   AssignToArrayRange(Builder, Address, Four8, 109, 113);
3033 
3034   return false;
3035 }
3036 
3037 bool
3038 PPC64_SVR4_TargetCodeGenInfo::initDwarfEHRegSizeTable(
3039   CodeGen::CodeGenFunction &CGF,
3040   llvm::Value *Address) const {
3041 
3042   return PPC64_initDwarfEHRegSizeTable(CGF, Address);
3043 }
3044 
3045 bool
3046 PPC64TargetCodeGenInfo::initDwarfEHRegSizeTable(CodeGen::CodeGenFunction &CGF,
3047                                                 llvm::Value *Address) const {
3048 
3049   return PPC64_initDwarfEHRegSizeTable(CGF, Address);
3050 }
3051 
3052 //===----------------------------------------------------------------------===//
3053 // ARM ABI Implementation
3054 //===----------------------------------------------------------------------===//
3055 
3056 namespace {
3057 
3058 class ARMABIInfo : public ABIInfo {
3059 public:
3060   enum ABIKind {
3061     APCS = 0,
3062     AAPCS = 1,
3063     AAPCS_VFP
3064   };
3065 
3066 private:
3067   ABIKind Kind;
3068 
3069 public:
3070   ARMABIInfo(CodeGenTypes &CGT, ABIKind _Kind) : ABIInfo(CGT), Kind(_Kind) {
3071     setRuntimeCC();
3072   }
3073 
3074   bool isEABI() const {
3075     StringRef Env = getTarget().getTriple().getEnvironmentName();
3076     return (Env == "gnueabi" || Env == "eabi" ||
3077             Env == "android" || Env == "androideabi");
3078   }
3079 
3080   ABIKind getABIKind() const { return Kind; }
3081 
3082 private:
3083   ABIArgInfo classifyReturnType(QualType RetTy) const;
3084   ABIArgInfo classifyArgumentType(QualType RetTy, int *VFPRegs,
3085                                   unsigned &AllocatedVFP,
3086                                   bool &IsHA) const;
3087   bool isIllegalVectorType(QualType Ty) const;
3088 
3089   virtual void computeInfo(CGFunctionInfo &FI) const;
3090 
3091   virtual llvm::Value *EmitVAArg(llvm::Value *VAListAddr, QualType Ty,
3092                                  CodeGenFunction &CGF) const;
3093 
3094   llvm::CallingConv::ID getLLVMDefaultCC() const;
3095   llvm::CallingConv::ID getABIDefaultCC() const;
3096   void setRuntimeCC();
3097 };
3098 
3099 class ARMTargetCodeGenInfo : public TargetCodeGenInfo {
3100 public:
3101   ARMTargetCodeGenInfo(CodeGenTypes &CGT, ARMABIInfo::ABIKind K)
3102     :TargetCodeGenInfo(new ARMABIInfo(CGT, K)) {}
3103 
3104   const ARMABIInfo &getABIInfo() const {
3105     return static_cast<const ARMABIInfo&>(TargetCodeGenInfo::getABIInfo());
3106   }
3107 
3108   int getDwarfEHStackPointer(CodeGen::CodeGenModule &M) const {
3109     return 13;
3110   }
3111 
3112   StringRef getARCRetainAutoreleasedReturnValueMarker() const {
3113     return "mov\tr7, r7\t\t@ marker for objc_retainAutoreleaseReturnValue";
3114   }
3115 
3116   bool initDwarfEHRegSizeTable(CodeGen::CodeGenFunction &CGF,
3117                                llvm::Value *Address) const {
3118     llvm::Value *Four8 = llvm::ConstantInt::get(CGF.Int8Ty, 4);
3119 
3120     // 0-15 are the 16 integer registers.
3121     AssignToArrayRange(CGF.Builder, Address, Four8, 0, 15);
3122     return false;
3123   }
3124 
3125   unsigned getSizeOfUnwindException() const {
3126     if (getABIInfo().isEABI()) return 88;
3127     return TargetCodeGenInfo::getSizeOfUnwindException();
3128   }
3129 
3130   void SetTargetAttributes(const Decl *D, llvm::GlobalValue *GV,
3131                            CodeGen::CodeGenModule &CGM) const {
3132     const FunctionDecl *FD = dyn_cast<FunctionDecl>(D);
3133     if (!FD)
3134       return;
3135 
3136     const ARMInterruptAttr *Attr = FD->getAttr<ARMInterruptAttr>();
3137     if (!Attr)
3138       return;
3139 
3140     const char *Kind;
3141     switch (Attr->getInterrupt()) {
3142     case ARMInterruptAttr::Generic: Kind = ""; break;
3143     case ARMInterruptAttr::IRQ:     Kind = "IRQ"; break;
3144     case ARMInterruptAttr::FIQ:     Kind = "FIQ"; break;
3145     case ARMInterruptAttr::SWI:     Kind = "SWI"; break;
3146     case ARMInterruptAttr::ABORT:   Kind = "ABORT"; break;
3147     case ARMInterruptAttr::UNDEF:   Kind = "UNDEF"; break;
3148     }
3149 
3150     llvm::Function *Fn = cast<llvm::Function>(GV);
3151 
3152     Fn->addFnAttr("interrupt", Kind);
3153 
3154     if (cast<ARMABIInfo>(getABIInfo()).getABIKind() == ARMABIInfo::APCS)
3155       return;
3156 
3157     // AAPCS guarantees that sp will be 8-byte aligned on any public interface,
3158     // however this is not necessarily true on taking any interrupt. Instruct
3159     // the backend to perform a realignment as part of the function prologue.
3160     llvm::AttrBuilder B;
3161     B.addStackAlignmentAttr(8);
3162     Fn->addAttributes(llvm::AttributeSet::FunctionIndex,
3163                       llvm::AttributeSet::get(CGM.getLLVMContext(),
3164                                               llvm::AttributeSet::FunctionIndex,
3165                                               B));
3166   }
3167 
3168 };
3169 
3170 }
3171 
3172 void ARMABIInfo::computeInfo(CGFunctionInfo &FI) const {
3173   // To correctly handle Homogeneous Aggregate, we need to keep track of the
3174   // VFP registers allocated so far.
3175   // C.1.vfp If the argument is a VFP CPRC and there are sufficient consecutive
3176   // VFP registers of the appropriate type unallocated then the argument is
3177   // allocated to the lowest-numbered sequence of such registers.
3178   // C.2.vfp If the argument is a VFP CPRC then any VFP registers that are
3179   // unallocated are marked as unavailable.
3180   unsigned AllocatedVFP = 0;
3181   int VFPRegs[16] = { 0 };
3182   FI.getReturnInfo() = classifyReturnType(FI.getReturnType());
3183   for (CGFunctionInfo::arg_iterator it = FI.arg_begin(), ie = FI.arg_end();
3184        it != ie; ++it) {
3185     unsigned PreAllocation = AllocatedVFP;
3186     bool IsHA = false;
3187     // 6.1.2.3 There is one VFP co-processor register class using registers
3188     // s0-s15 (d0-d7) for passing arguments.
3189     const unsigned NumVFPs = 16;
3190     it->info = classifyArgumentType(it->type, VFPRegs, AllocatedVFP, IsHA);
3191     // If we do not have enough VFP registers for the HA, any VFP registers
3192     // that are unallocated are marked as unavailable. To achieve this, we add
3193     // padding of (NumVFPs - PreAllocation) floats.
3194     if (IsHA && AllocatedVFP > NumVFPs && PreAllocation < NumVFPs) {
3195       llvm::Type *PaddingTy = llvm::ArrayType::get(
3196           llvm::Type::getFloatTy(getVMContext()), NumVFPs - PreAllocation);
3197       it->info = ABIArgInfo::getExpandWithPadding(false, PaddingTy);
3198     }
3199   }
3200 
3201   // Always honor user-specified calling convention.
3202   if (FI.getCallingConvention() != llvm::CallingConv::C)
3203     return;
3204 
3205   llvm::CallingConv::ID cc = getRuntimeCC();
3206   if (cc != llvm::CallingConv::C)
3207     FI.setEffectiveCallingConvention(cc);
3208 }
3209 
3210 /// Return the default calling convention that LLVM will use.
3211 llvm::CallingConv::ID ARMABIInfo::getLLVMDefaultCC() const {
3212   // The default calling convention that LLVM will infer.
3213   if (getTarget().getTriple().getEnvironmentName()=="gnueabihf")
3214     return llvm::CallingConv::ARM_AAPCS_VFP;
3215   else if (isEABI())
3216     return llvm::CallingConv::ARM_AAPCS;
3217   else
3218     return llvm::CallingConv::ARM_APCS;
3219 }
3220 
3221 /// Return the calling convention that our ABI would like us to use
3222 /// as the C calling convention.
3223 llvm::CallingConv::ID ARMABIInfo::getABIDefaultCC() const {
3224   switch (getABIKind()) {
3225   case APCS: return llvm::CallingConv::ARM_APCS;
3226   case AAPCS: return llvm::CallingConv::ARM_AAPCS;
3227   case AAPCS_VFP: return llvm::CallingConv::ARM_AAPCS_VFP;
3228   }
3229   llvm_unreachable("bad ABI kind");
3230 }
3231 
3232 void ARMABIInfo::setRuntimeCC() {
3233   assert(getRuntimeCC() == llvm::CallingConv::C);
3234 
3235   // Don't muddy up the IR with a ton of explicit annotations if
3236   // they'd just match what LLVM will infer from the triple.
3237   llvm::CallingConv::ID abiCC = getABIDefaultCC();
3238   if (abiCC != getLLVMDefaultCC())
3239     RuntimeCC = abiCC;
3240 }
3241 
3242 /// isHomogeneousAggregate - Return true if a type is an AAPCS-VFP homogeneous
3243 /// aggregate.  If HAMembers is non-null, the number of base elements
3244 /// contained in the type is returned through it; this is used for the
3245 /// recursive calls that check aggregate component types.
3246 static bool isHomogeneousAggregate(QualType Ty, const Type *&Base,
3247                                    ASTContext &Context,
3248                                    uint64_t *HAMembers = 0) {
3249   uint64_t Members = 0;
3250   if (const ConstantArrayType *AT = Context.getAsConstantArrayType(Ty)) {
3251     if (!isHomogeneousAggregate(AT->getElementType(), Base, Context, &Members))
3252       return false;
3253     Members *= AT->getSize().getZExtValue();
3254   } else if (const RecordType *RT = Ty->getAs<RecordType>()) {
3255     const RecordDecl *RD = RT->getDecl();
3256     if (RD->hasFlexibleArrayMember())
3257       return false;
3258 
3259     Members = 0;
3260     for (RecordDecl::field_iterator i = RD->field_begin(), e = RD->field_end();
3261          i != e; ++i) {
3262       const FieldDecl *FD = *i;
3263       uint64_t FldMembers;
3264       if (!isHomogeneousAggregate(FD->getType(), Base, Context, &FldMembers))
3265         return false;
3266 
3267       Members = (RD->isUnion() ?
3268                  std::max(Members, FldMembers) : Members + FldMembers);
3269     }
3270   } else {
3271     Members = 1;
3272     if (const ComplexType *CT = Ty->getAs<ComplexType>()) {
3273       Members = 2;
3274       Ty = CT->getElementType();
3275     }
3276 
3277     // Homogeneous aggregates for AAPCS-VFP must have base types of float,
3278     // double, or 64-bit or 128-bit vectors.
3279     if (const BuiltinType *BT = Ty->getAs<BuiltinType>()) {
3280       if (BT->getKind() != BuiltinType::Float &&
3281           BT->getKind() != BuiltinType::Double &&
3282           BT->getKind() != BuiltinType::LongDouble)
3283         return false;
3284     } else if (const VectorType *VT = Ty->getAs<VectorType>()) {
3285       unsigned VecSize = Context.getTypeSize(VT);
3286       if (VecSize != 64 && VecSize != 128)
3287         return false;
3288     } else {
3289       return false;
3290     }
3291 
3292     // The base type must be the same for all members.  Vector types of the
3293     // same total size are treated as being equivalent here.
3294     const Type *TyPtr = Ty.getTypePtr();
3295     if (!Base)
3296       Base = TyPtr;
3297     if (Base != TyPtr &&
3298         (!Base->isVectorType() || !TyPtr->isVectorType() ||
3299          Context.getTypeSize(Base) != Context.getTypeSize(TyPtr)))
3300       return false;
3301   }
3302 
3303   // Homogeneous Aggregates can have at most 4 members of the base type.
3304   if (HAMembers)
3305     *HAMembers = Members;
3306 
3307   return (Members > 0 && Members <= 4);
3308 }
3309 
3310 /// markAllocatedVFPs - update VFPRegs according to the alignment and
3311 /// number of VFP registers (unit is S register) requested.
3312 static void markAllocatedVFPs(int *VFPRegs, unsigned &AllocatedVFP,
3313                               unsigned Alignment,
3314                               unsigned NumRequired) {
3315   // Early Exit.
3316   if (AllocatedVFP >= 16)
3317     return;
3318   // C.1.vfp If the argument is a VFP CPRC and there are sufficient consecutive
3319   // VFP registers of the appropriate type unallocated then the argument is
3320   // allocated to the lowest-numbered sequence of such registers.
3321   for (unsigned I = 0; I < 16; I += Alignment) {
3322     bool FoundSlot = true;
3323     for (unsigned J = I, JEnd = I + NumRequired; J < JEnd; J++)
3324       if (J >= 16 || VFPRegs[J]) {
3325          FoundSlot = false;
3326          break;
3327       }
3328     if (FoundSlot) {
3329       for (unsigned J = I, JEnd = I + NumRequired; J < JEnd; J++)
3330         VFPRegs[J] = 1;
3331       AllocatedVFP += NumRequired;
3332       return;
3333     }
3334   }
3335   // C.2.vfp If the argument is a VFP CPRC then any VFP registers that are
3336   // unallocated are marked as unavailable.
3337   for (unsigned I = 0; I < 16; I++)
3338     VFPRegs[I] = 1;
3339   AllocatedVFP = 17; // We do not have enough VFP registers.
3340 }
3341 
3342 ABIArgInfo ARMABIInfo::classifyArgumentType(QualType Ty, int *VFPRegs,
3343                                             unsigned &AllocatedVFP,
3344                                             bool &IsHA) const {
3345   // We update number of allocated VFPs according to
3346   // 6.1.2.1 The following argument types are VFP CPRCs:
3347   //   A single-precision floating-point type (including promoted
3348   //   half-precision types); A double-precision floating-point type;
3349   //   A 64-bit or 128-bit containerized vector type; Homogeneous Aggregate
3350   //   with a Base Type of a single- or double-precision floating-point type,
3351   //   64-bit containerized vectors or 128-bit containerized vectors with one
3352   //   to four Elements.
3353 
3354   // Handle illegal vector types here.
3355   if (isIllegalVectorType(Ty)) {
3356     uint64_t Size = getContext().getTypeSize(Ty);
3357     if (Size <= 32) {
3358       llvm::Type *ResType =
3359           llvm::Type::getInt32Ty(getVMContext());
3360       return ABIArgInfo::getDirect(ResType);
3361     }
3362     if (Size == 64) {
3363       llvm::Type *ResType = llvm::VectorType::get(
3364           llvm::Type::getInt32Ty(getVMContext()), 2);
3365       markAllocatedVFPs(VFPRegs, AllocatedVFP, 2, 2);
3366       return ABIArgInfo::getDirect(ResType);
3367     }
3368     if (Size == 128) {
3369       llvm::Type *ResType = llvm::VectorType::get(
3370           llvm::Type::getInt32Ty(getVMContext()), 4);
3371       markAllocatedVFPs(VFPRegs, AllocatedVFP, 4, 4);
3372       return ABIArgInfo::getDirect(ResType);
3373     }
3374     return ABIArgInfo::getIndirect(0, /*ByVal=*/false);
3375   }
3376   // Update VFPRegs for legal vector types.
3377   if (const VectorType *VT = Ty->getAs<VectorType>()) {
3378     uint64_t Size = getContext().getTypeSize(VT);
3379     // Size of a legal vector should be power of 2 and above 64.
3380     markAllocatedVFPs(VFPRegs, AllocatedVFP, Size >= 128 ? 4 : 2, Size / 32);
3381   }
3382   // Update VFPRegs for floating point types.
3383   if (const BuiltinType *BT = Ty->getAs<BuiltinType>()) {
3384     if (BT->getKind() == BuiltinType::Half ||
3385         BT->getKind() == BuiltinType::Float)
3386       markAllocatedVFPs(VFPRegs, AllocatedVFP, 1, 1);
3387     if (BT->getKind() == BuiltinType::Double ||
3388         BT->getKind() == BuiltinType::LongDouble)
3389       markAllocatedVFPs(VFPRegs, AllocatedVFP, 2, 2);
3390   }
3391 
3392   if (!isAggregateTypeForABI(Ty)) {
3393     // Treat an enum type as its underlying type.
3394     if (const EnumType *EnumTy = Ty->getAs<EnumType>())
3395       Ty = EnumTy->getDecl()->getIntegerType();
3396 
3397     return (Ty->isPromotableIntegerType() ?
3398             ABIArgInfo::getExtend() : ABIArgInfo::getDirect());
3399   }
3400 
3401   if (CGCXXABI::RecordArgABI RAA = getRecordArgABI(Ty, getCXXABI()))
3402     return ABIArgInfo::getIndirect(0, RAA == CGCXXABI::RAA_DirectInMemory);
3403 
3404   // Ignore empty records.
3405   if (isEmptyRecord(getContext(), Ty, true))
3406     return ABIArgInfo::getIgnore();
3407 
3408   if (getABIKind() == ARMABIInfo::AAPCS_VFP) {
3409     // Homogeneous Aggregates need to be expanded when we can fit the aggregate
3410     // into VFP registers.
3411     const Type *Base = 0;
3412     uint64_t Members = 0;
3413     if (isHomogeneousAggregate(Ty, Base, getContext(), &Members)) {
3414       assert(Base && "Base class should be set for homogeneous aggregate");
3415       // Base can be a floating-point or a vector.
3416       if (Base->isVectorType()) {
3417         // ElementSize is in number of floats.
3418         unsigned ElementSize = getContext().getTypeSize(Base) == 64 ? 2 : 4;
3419         markAllocatedVFPs(VFPRegs, AllocatedVFP, ElementSize,
3420                           Members * ElementSize);
3421       } else if (Base->isSpecificBuiltinType(BuiltinType::Float))
3422         markAllocatedVFPs(VFPRegs, AllocatedVFP, 1, Members);
3423       else {
3424         assert(Base->isSpecificBuiltinType(BuiltinType::Double) ||
3425                Base->isSpecificBuiltinType(BuiltinType::LongDouble));
3426         markAllocatedVFPs(VFPRegs, AllocatedVFP, 2, Members * 2);
3427       }
3428       IsHA = true;
3429       return ABIArgInfo::getExpand();
3430     }
3431   }
3432 
3433   // Support byval for ARM.
3434   // The ABI alignment for APCS is 4-byte and for AAPCS at least 4-byte and at
3435   // most 8-byte. We realign the indirect argument if type alignment is bigger
3436   // than ABI alignment.
3437   uint64_t ABIAlign = 4;
3438   uint64_t TyAlign = getContext().getTypeAlign(Ty) / 8;
3439   if (getABIKind() == ARMABIInfo::AAPCS_VFP ||
3440       getABIKind() == ARMABIInfo::AAPCS)
3441     ABIAlign = std::min(std::max(TyAlign, (uint64_t)4), (uint64_t)8);
3442   if (getContext().getTypeSizeInChars(Ty) > CharUnits::fromQuantity(64)) {
3443     return ABIArgInfo::getIndirect(0, /*ByVal=*/true,
3444            /*Realign=*/TyAlign > ABIAlign);
3445   }
3446 
3447   // Otherwise, pass by coercing to a structure of the appropriate size.
3448   llvm::Type* ElemTy;
3449   unsigned SizeRegs;
3450   // FIXME: Try to match the types of the arguments more accurately where
3451   // we can.
3452   if (getContext().getTypeAlign(Ty) <= 32) {
3453     ElemTy = llvm::Type::getInt32Ty(getVMContext());
3454     SizeRegs = (getContext().getTypeSize(Ty) + 31) / 32;
3455   } else {
3456     ElemTy = llvm::Type::getInt64Ty(getVMContext());
3457     SizeRegs = (getContext().getTypeSize(Ty) + 63) / 64;
3458   }
3459 
3460   llvm::Type *STy =
3461     llvm::StructType::get(llvm::ArrayType::get(ElemTy, SizeRegs), NULL);
3462   return ABIArgInfo::getDirect(STy);
3463 }
3464 
3465 static bool isIntegerLikeType(QualType Ty, ASTContext &Context,
3466                               llvm::LLVMContext &VMContext) {
3467   // APCS, C Language Calling Conventions, Non-Simple Return Values: A structure
3468   // is called integer-like if its size is less than or equal to one word, and
3469   // the offset of each of its addressable sub-fields is zero.
3470 
3471   uint64_t Size = Context.getTypeSize(Ty);
3472 
3473   // Check that the type fits in a word.
3474   if (Size > 32)
3475     return false;
3476 
3477   // FIXME: Handle vector types!
3478   if (Ty->isVectorType())
3479     return false;
3480 
3481   // Float types are never treated as "integer like".
3482   if (Ty->isRealFloatingType())
3483     return false;
3484 
3485   // If this is a builtin or pointer type then it is ok.
3486   if (Ty->getAs<BuiltinType>() || Ty->isPointerType())
3487     return true;
3488 
3489   // Small complex integer types are "integer like".
3490   if (const ComplexType *CT = Ty->getAs<ComplexType>())
3491     return isIntegerLikeType(CT->getElementType(), Context, VMContext);
3492 
3493   // Single element and zero sized arrays should be allowed, by the definition
3494   // above, but they are not.
3495 
3496   // Otherwise, it must be a record type.
3497   const RecordType *RT = Ty->getAs<RecordType>();
3498   if (!RT) return false;
3499 
3500   // Ignore records with flexible arrays.
3501   const RecordDecl *RD = RT->getDecl();
3502   if (RD->hasFlexibleArrayMember())
3503     return false;
3504 
3505   // Check that all sub-fields are at offset 0, and are themselves "integer
3506   // like".
3507   const ASTRecordLayout &Layout = Context.getASTRecordLayout(RD);
3508 
3509   bool HadField = false;
3510   unsigned idx = 0;
3511   for (RecordDecl::field_iterator i = RD->field_begin(), e = RD->field_end();
3512        i != e; ++i, ++idx) {
3513     const FieldDecl *FD = *i;
3514 
3515     // Bit-fields are not addressable, we only need to verify they are "integer
3516     // like". We still have to disallow a subsequent non-bitfield, for example:
3517     //   struct { int : 0; int x }
3518     // is non-integer like according to gcc.
3519     if (FD->isBitField()) {
3520       if (!RD->isUnion())
3521         HadField = true;
3522 
3523       if (!isIntegerLikeType(FD->getType(), Context, VMContext))
3524         return false;
3525 
3526       continue;
3527     }
3528 
3529     // Check if this field is at offset 0.
3530     if (Layout.getFieldOffset(idx) != 0)
3531       return false;
3532 
3533     if (!isIntegerLikeType(FD->getType(), Context, VMContext))
3534       return false;
3535 
3536     // Only allow at most one field in a structure. This doesn't match the
3537     // wording above, but follows gcc in situations with a field following an
3538     // empty structure.
3539     if (!RD->isUnion()) {
3540       if (HadField)
3541         return false;
3542 
3543       HadField = true;
3544     }
3545   }
3546 
3547   return true;
3548 }
3549 
3550 ABIArgInfo ARMABIInfo::classifyReturnType(QualType RetTy) const {
3551   if (RetTy->isVoidType())
3552     return ABIArgInfo::getIgnore();
3553 
3554   // Large vector types should be returned via memory.
3555   if (RetTy->isVectorType() && getContext().getTypeSize(RetTy) > 128)
3556     return ABIArgInfo::getIndirect(0);
3557 
3558   if (!isAggregateTypeForABI(RetTy)) {
3559     // Treat an enum type as its underlying type.
3560     if (const EnumType *EnumTy = RetTy->getAs<EnumType>())
3561       RetTy = EnumTy->getDecl()->getIntegerType();
3562 
3563     return (RetTy->isPromotableIntegerType() ?
3564             ABIArgInfo::getExtend() : ABIArgInfo::getDirect());
3565   }
3566 
3567   // Structures with either a non-trivial destructor or a non-trivial
3568   // copy constructor are always indirect.
3569   if (isRecordReturnIndirect(RetTy, getCXXABI()))
3570     return ABIArgInfo::getIndirect(0, /*ByVal=*/false);
3571 
3572   // Are we following APCS?
3573   if (getABIKind() == APCS) {
3574     if (isEmptyRecord(getContext(), RetTy, false))
3575       return ABIArgInfo::getIgnore();
3576 
3577     // Complex types are all returned as packed integers.
3578     //
3579     // FIXME: Consider using 2 x vector types if the back end handles them
3580     // correctly.
3581     if (RetTy->isAnyComplexType())
3582       return ABIArgInfo::getDirect(llvm::IntegerType::get(getVMContext(),
3583                                               getContext().getTypeSize(RetTy)));
3584 
3585     // Integer like structures are returned in r0.
3586     if (isIntegerLikeType(RetTy, getContext(), getVMContext())) {
3587       // Return in the smallest viable integer type.
3588       uint64_t Size = getContext().getTypeSize(RetTy);
3589       if (Size <= 8)
3590         return ABIArgInfo::getDirect(llvm::Type::getInt8Ty(getVMContext()));
3591       if (Size <= 16)
3592         return ABIArgInfo::getDirect(llvm::Type::getInt16Ty(getVMContext()));
3593       return ABIArgInfo::getDirect(llvm::Type::getInt32Ty(getVMContext()));
3594     }
3595 
3596     // Otherwise return in memory.
3597     return ABIArgInfo::getIndirect(0);
3598   }
3599 
3600   // Otherwise this is an AAPCS variant.
3601 
3602   if (isEmptyRecord(getContext(), RetTy, true))
3603     return ABIArgInfo::getIgnore();
3604 
3605   // Check for homogeneous aggregates with AAPCS-VFP.
3606   if (getABIKind() == AAPCS_VFP) {
3607     const Type *Base = 0;
3608     if (isHomogeneousAggregate(RetTy, Base, getContext())) {
3609       assert(Base && "Base class should be set for homogeneous aggregate");
3610       // Homogeneous Aggregates are returned directly.
3611       return ABIArgInfo::getDirect();
3612     }
3613   }
3614 
3615   // Aggregates <= 4 bytes are returned in r0; other aggregates
3616   // are returned indirectly.
3617   uint64_t Size = getContext().getTypeSize(RetTy);
3618   if (Size <= 32) {
3619     // Return in the smallest viable integer type.
3620     if (Size <= 8)
3621       return ABIArgInfo::getDirect(llvm::Type::getInt8Ty(getVMContext()));
3622     if (Size <= 16)
3623       return ABIArgInfo::getDirect(llvm::Type::getInt16Ty(getVMContext()));
3624     return ABIArgInfo::getDirect(llvm::Type::getInt32Ty(getVMContext()));
3625   }
3626 
3627   return ABIArgInfo::getIndirect(0);
3628 }
3629 
3630 /// isIllegalVector - check whether Ty is an illegal vector type.
3631 bool ARMABIInfo::isIllegalVectorType(QualType Ty) const {
3632   if (const VectorType *VT = Ty->getAs<VectorType>()) {
3633     // Check whether VT is legal.
3634     unsigned NumElements = VT->getNumElements();
3635     uint64_t Size = getContext().getTypeSize(VT);
3636     // NumElements should be power of 2.
3637     if ((NumElements & (NumElements - 1)) != 0)
3638       return true;
3639     // Size should be greater than 32 bits.
3640     return Size <= 32;
3641   }
3642   return false;
3643 }
3644 
3645 llvm::Value *ARMABIInfo::EmitVAArg(llvm::Value *VAListAddr, QualType Ty,
3646                                    CodeGenFunction &CGF) const {
3647   llvm::Type *BP = CGF.Int8PtrTy;
3648   llvm::Type *BPP = CGF.Int8PtrPtrTy;
3649 
3650   CGBuilderTy &Builder = CGF.Builder;
3651   llvm::Value *VAListAddrAsBPP = Builder.CreateBitCast(VAListAddr, BPP, "ap");
3652   llvm::Value *Addr = Builder.CreateLoad(VAListAddrAsBPP, "ap.cur");
3653 
3654   if (isEmptyRecord(getContext(), Ty, true)) {
3655     // These are ignored for parameter passing purposes.
3656     llvm::Type *PTy = llvm::PointerType::getUnqual(CGF.ConvertType(Ty));
3657     return Builder.CreateBitCast(Addr, PTy);
3658   }
3659 
3660   uint64_t Size = CGF.getContext().getTypeSize(Ty) / 8;
3661   uint64_t TyAlign = CGF.getContext().getTypeAlign(Ty) / 8;
3662   bool IsIndirect = false;
3663 
3664   // The ABI alignment for 64-bit or 128-bit vectors is 8 for AAPCS and 4 for
3665   // APCS. For AAPCS, the ABI alignment is at least 4-byte and at most 8-byte.
3666   if (getABIKind() == ARMABIInfo::AAPCS_VFP ||
3667       getABIKind() == ARMABIInfo::AAPCS)
3668     TyAlign = std::min(std::max(TyAlign, (uint64_t)4), (uint64_t)8);
3669   else
3670     TyAlign = 4;
3671   // Use indirect if size of the illegal vector is bigger than 16 bytes.
3672   if (isIllegalVectorType(Ty) && Size > 16) {
3673     IsIndirect = true;
3674     Size = 4;
3675     TyAlign = 4;
3676   }
3677 
3678   // Handle address alignment for ABI alignment > 4 bytes.
3679   if (TyAlign > 4) {
3680     assert((TyAlign & (TyAlign - 1)) == 0 &&
3681            "Alignment is not power of 2!");
3682     llvm::Value *AddrAsInt = Builder.CreatePtrToInt(Addr, CGF.Int32Ty);
3683     AddrAsInt = Builder.CreateAdd(AddrAsInt, Builder.getInt32(TyAlign - 1));
3684     AddrAsInt = Builder.CreateAnd(AddrAsInt, Builder.getInt32(~(TyAlign - 1)));
3685     Addr = Builder.CreateIntToPtr(AddrAsInt, BP, "ap.align");
3686   }
3687 
3688   uint64_t Offset =
3689     llvm::RoundUpToAlignment(Size, 4);
3690   llvm::Value *NextAddr =
3691     Builder.CreateGEP(Addr, llvm::ConstantInt::get(CGF.Int32Ty, Offset),
3692                       "ap.next");
3693   Builder.CreateStore(NextAddr, VAListAddrAsBPP);
3694 
3695   if (IsIndirect)
3696     Addr = Builder.CreateLoad(Builder.CreateBitCast(Addr, BPP));
3697   else if (TyAlign < CGF.getContext().getTypeAlign(Ty) / 8) {
3698     // We can't directly cast ap.cur to pointer to a vector type, since ap.cur
3699     // may not be correctly aligned for the vector type. We create an aligned
3700     // temporary space and copy the content over from ap.cur to the temporary
3701     // space. This is necessary if the natural alignment of the type is greater
3702     // than the ABI alignment.
3703     llvm::Type *I8PtrTy = Builder.getInt8PtrTy();
3704     CharUnits CharSize = getContext().getTypeSizeInChars(Ty);
3705     llvm::Value *AlignedTemp = CGF.CreateTempAlloca(CGF.ConvertType(Ty),
3706                                                     "var.align");
3707     llvm::Value *Dst = Builder.CreateBitCast(AlignedTemp, I8PtrTy);
3708     llvm::Value *Src = Builder.CreateBitCast(Addr, I8PtrTy);
3709     Builder.CreateMemCpy(Dst, Src,
3710         llvm::ConstantInt::get(CGF.IntPtrTy, CharSize.getQuantity()),
3711         TyAlign, false);
3712     Addr = AlignedTemp; //The content is in aligned location.
3713   }
3714   llvm::Type *PTy =
3715     llvm::PointerType::getUnqual(CGF.ConvertType(Ty));
3716   llvm::Value *AddrTyped = Builder.CreateBitCast(Addr, PTy);
3717 
3718   return AddrTyped;
3719 }
3720 
3721 namespace {
3722 
3723 class NaClARMABIInfo : public ABIInfo {
3724  public:
3725   NaClARMABIInfo(CodeGen::CodeGenTypes &CGT, ARMABIInfo::ABIKind Kind)
3726       : ABIInfo(CGT), PInfo(CGT), NInfo(CGT, Kind) {}
3727   virtual void computeInfo(CGFunctionInfo &FI) const;
3728   virtual llvm::Value *EmitVAArg(llvm::Value *VAListAddr, QualType Ty,
3729                                  CodeGenFunction &CGF) const;
3730  private:
3731   PNaClABIInfo PInfo; // Used for generating calls with pnaclcall callingconv.
3732   ARMABIInfo NInfo; // Used for everything else.
3733 };
3734 
3735 class NaClARMTargetCodeGenInfo : public TargetCodeGenInfo  {
3736  public:
3737   NaClARMTargetCodeGenInfo(CodeGen::CodeGenTypes &CGT, ARMABIInfo::ABIKind Kind)
3738       : TargetCodeGenInfo(new NaClARMABIInfo(CGT, Kind)) {}
3739 };
3740 
3741 }
3742 
3743 void NaClARMABIInfo::computeInfo(CGFunctionInfo &FI) const {
3744   if (FI.getASTCallingConvention() == CC_PnaclCall)
3745     PInfo.computeInfo(FI);
3746   else
3747     static_cast<const ABIInfo&>(NInfo).computeInfo(FI);
3748 }
3749 
3750 llvm::Value *NaClARMABIInfo::EmitVAArg(llvm::Value *VAListAddr, QualType Ty,
3751                                        CodeGenFunction &CGF) const {
3752   // Always use the native convention; calling pnacl-style varargs functions
3753   // is unsupported.
3754   return static_cast<const ABIInfo&>(NInfo).EmitVAArg(VAListAddr, Ty, CGF);
3755 }
3756 
3757 //===----------------------------------------------------------------------===//
3758 // AArch64 ABI Implementation
3759 //===----------------------------------------------------------------------===//
3760 
3761 namespace {
3762 
3763 class AArch64ABIInfo : public ABIInfo {
3764 public:
3765   AArch64ABIInfo(CodeGenTypes &CGT) : ABIInfo(CGT) {}
3766 
3767 private:
3768   // The AArch64 PCS is explicit about return types and argument types being
3769   // handled identically, so we don't need to draw a distinction between
3770   // Argument and Return classification.
3771   ABIArgInfo classifyGenericType(QualType Ty, int &FreeIntRegs,
3772                                  int &FreeVFPRegs) const;
3773 
3774   ABIArgInfo tryUseRegs(QualType Ty, int &FreeRegs, int RegsNeeded, bool IsInt,
3775                         llvm::Type *DirectTy = 0) const;
3776 
3777   virtual void computeInfo(CGFunctionInfo &FI) const;
3778 
3779   virtual llvm::Value *EmitVAArg(llvm::Value *VAListAddr, QualType Ty,
3780                                  CodeGenFunction &CGF) const;
3781 };
3782 
3783 class AArch64TargetCodeGenInfo : public TargetCodeGenInfo {
3784 public:
3785   AArch64TargetCodeGenInfo(CodeGenTypes &CGT)
3786     :TargetCodeGenInfo(new AArch64ABIInfo(CGT)) {}
3787 
3788   const AArch64ABIInfo &getABIInfo() const {
3789     return static_cast<const AArch64ABIInfo&>(TargetCodeGenInfo::getABIInfo());
3790   }
3791 
3792   int getDwarfEHStackPointer(CodeGen::CodeGenModule &M) const {
3793     return 31;
3794   }
3795 
3796   bool initDwarfEHRegSizeTable(CodeGen::CodeGenFunction &CGF,
3797                                llvm::Value *Address) const {
3798     // 0-31 are x0-x30 and sp: 8 bytes each
3799     llvm::Value *Eight8 = llvm::ConstantInt::get(CGF.Int8Ty, 8);
3800     AssignToArrayRange(CGF.Builder, Address, Eight8, 0, 31);
3801 
3802     // 64-95 are v0-v31: 16 bytes each
3803     llvm::Value *Sixteen8 = llvm::ConstantInt::get(CGF.Int8Ty, 16);
3804     AssignToArrayRange(CGF.Builder, Address, Sixteen8, 64, 95);
3805 
3806     return false;
3807   }
3808 
3809 };
3810 
3811 }
3812 
3813 void AArch64ABIInfo::computeInfo(CGFunctionInfo &FI) const {
3814   int FreeIntRegs = 8, FreeVFPRegs = 8;
3815 
3816   FI.getReturnInfo() = classifyGenericType(FI.getReturnType(),
3817                                            FreeIntRegs, FreeVFPRegs);
3818 
3819   FreeIntRegs = FreeVFPRegs = 8;
3820   for (CGFunctionInfo::arg_iterator it = FI.arg_begin(), ie = FI.arg_end();
3821        it != ie; ++it) {
3822     it->info = classifyGenericType(it->type, FreeIntRegs, FreeVFPRegs);
3823 
3824   }
3825 }
3826 
3827 ABIArgInfo
3828 AArch64ABIInfo::tryUseRegs(QualType Ty, int &FreeRegs, int RegsNeeded,
3829                            bool IsInt, llvm::Type *DirectTy) const {
3830   if (FreeRegs >= RegsNeeded) {
3831     FreeRegs -= RegsNeeded;
3832     return ABIArgInfo::getDirect(DirectTy);
3833   }
3834 
3835   llvm::Type *Padding = 0;
3836 
3837   // We need padding so that later arguments don't get filled in anyway. That
3838   // wouldn't happen if only ByVal arguments followed in the same category, but
3839   // a large structure will simply seem to be a pointer as far as LLVM is
3840   // concerned.
3841   if (FreeRegs > 0) {
3842     if (IsInt)
3843       Padding = llvm::Type::getInt64Ty(getVMContext());
3844     else
3845       Padding = llvm::Type::getFloatTy(getVMContext());
3846 
3847     // Either [N x i64] or [N x float].
3848     Padding = llvm::ArrayType::get(Padding, FreeRegs);
3849     FreeRegs = 0;
3850   }
3851 
3852   return ABIArgInfo::getIndirect(getContext().getTypeAlign(Ty) / 8,
3853                                  /*IsByVal=*/ true, /*Realign=*/ false,
3854                                  Padding);
3855 }
3856 
3857 
3858 ABIArgInfo AArch64ABIInfo::classifyGenericType(QualType Ty,
3859                                                int &FreeIntRegs,
3860                                                int &FreeVFPRegs) const {
3861   // Can only occurs for return, but harmless otherwise.
3862   if (Ty->isVoidType())
3863     return ABIArgInfo::getIgnore();
3864 
3865   // Large vector types should be returned via memory. There's no such concept
3866   // in the ABI, but they'd be over 16 bytes anyway so no matter how they're
3867   // classified they'd go into memory (see B.3).
3868   if (Ty->isVectorType() && getContext().getTypeSize(Ty) > 128) {
3869     if (FreeIntRegs > 0)
3870       --FreeIntRegs;
3871     return ABIArgInfo::getIndirect(0, /*ByVal=*/false);
3872   }
3873 
3874   // All non-aggregate LLVM types have a concrete ABI representation so they can
3875   // be passed directly. After this block we're guaranteed to be in a
3876   // complicated case.
3877   if (!isAggregateTypeForABI(Ty)) {
3878     // Treat an enum type as its underlying type.
3879     if (const EnumType *EnumTy = Ty->getAs<EnumType>())
3880       Ty = EnumTy->getDecl()->getIntegerType();
3881 
3882     if (Ty->isFloatingType() || Ty->isVectorType())
3883       return tryUseRegs(Ty, FreeVFPRegs, /*RegsNeeded=*/ 1, /*IsInt=*/ false);
3884 
3885     assert(getContext().getTypeSize(Ty) <= 128 &&
3886            "unexpectedly large scalar type");
3887 
3888     int RegsNeeded = getContext().getTypeSize(Ty) > 64 ? 2 : 1;
3889 
3890     // If the type may need padding registers to ensure "alignment", we must be
3891     // careful when this is accounted for. Increasing the effective size covers
3892     // all cases.
3893     if (getContext().getTypeAlign(Ty) == 128)
3894       RegsNeeded += FreeIntRegs % 2 != 0;
3895 
3896     return tryUseRegs(Ty, FreeIntRegs, RegsNeeded, /*IsInt=*/ true);
3897   }
3898 
3899   if (CGCXXABI::RecordArgABI RAA = getRecordArgABI(Ty, getCXXABI())) {
3900     if (FreeIntRegs > 0 && RAA == CGCXXABI::RAA_Indirect)
3901       --FreeIntRegs;
3902     return ABIArgInfo::getIndirect(0, RAA == CGCXXABI::RAA_DirectInMemory);
3903   }
3904 
3905   if (isEmptyRecord(getContext(), Ty, true)) {
3906     if (!getContext().getLangOpts().CPlusPlus) {
3907       // Empty structs outside C++ mode are a GNU extension, so no ABI can
3908       // possibly tell us what to do. It turns out (I believe) that GCC ignores
3909       // the object for parameter-passsing purposes.
3910       return ABIArgInfo::getIgnore();
3911     }
3912 
3913     // The combination of C++98 9p5 (sizeof(struct) != 0) and the pseudocode
3914     // description of va_arg in the PCS require that an empty struct does
3915     // actually occupy space for parameter-passing. I'm hoping for a
3916     // clarification giving an explicit paragraph to point to in future.
3917     return tryUseRegs(Ty, FreeIntRegs, /*RegsNeeded=*/ 1, /*IsInt=*/ true,
3918                       llvm::Type::getInt8Ty(getVMContext()));
3919   }
3920 
3921   // Homogeneous vector aggregates get passed in registers or on the stack.
3922   const Type *Base = 0;
3923   uint64_t NumMembers = 0;
3924   if (isHomogeneousAggregate(Ty, Base, getContext(), &NumMembers)) {
3925     assert(Base && "Base class should be set for homogeneous aggregate");
3926     // Homogeneous aggregates are passed and returned directly.
3927     return tryUseRegs(Ty, FreeVFPRegs, /*RegsNeeded=*/ NumMembers,
3928                       /*IsInt=*/ false);
3929   }
3930 
3931   uint64_t Size = getContext().getTypeSize(Ty);
3932   if (Size <= 128) {
3933     // Small structs can use the same direct type whether they're in registers
3934     // or on the stack.
3935     llvm::Type *BaseTy;
3936     unsigned NumBases;
3937     int SizeInRegs = (Size + 63) / 64;
3938 
3939     if (getContext().getTypeAlign(Ty) == 128) {
3940       BaseTy = llvm::Type::getIntNTy(getVMContext(), 128);
3941       NumBases = 1;
3942 
3943       // If the type may need padding registers to ensure "alignment", we must
3944       // be careful when this is accounted for. Increasing the effective size
3945       // covers all cases.
3946       SizeInRegs += FreeIntRegs % 2 != 0;
3947     } else {
3948       BaseTy = llvm::Type::getInt64Ty(getVMContext());
3949       NumBases = SizeInRegs;
3950     }
3951     llvm::Type *DirectTy = llvm::ArrayType::get(BaseTy, NumBases);
3952 
3953     return tryUseRegs(Ty, FreeIntRegs, /*RegsNeeded=*/ SizeInRegs,
3954                       /*IsInt=*/ true, DirectTy);
3955   }
3956 
3957   // If the aggregate is > 16 bytes, it's passed and returned indirectly. In
3958   // LLVM terms the return uses an "sret" pointer, but that's handled elsewhere.
3959   --FreeIntRegs;
3960   return ABIArgInfo::getIndirect(0, /* byVal = */ false);
3961 }
3962 
3963 llvm::Value *AArch64ABIInfo::EmitVAArg(llvm::Value *VAListAddr, QualType Ty,
3964                                        CodeGenFunction &CGF) const {
3965   // The AArch64 va_list type and handling is specified in the Procedure Call
3966   // Standard, section B.4:
3967   //
3968   // struct {
3969   //   void *__stack;
3970   //   void *__gr_top;
3971   //   void *__vr_top;
3972   //   int __gr_offs;
3973   //   int __vr_offs;
3974   // };
3975 
3976   assert(!CGF.CGM.getDataLayout().isBigEndian()
3977          && "va_arg not implemented for big-endian AArch64");
3978 
3979   int FreeIntRegs = 8, FreeVFPRegs = 8;
3980   Ty = CGF.getContext().getCanonicalType(Ty);
3981   ABIArgInfo AI = classifyGenericType(Ty, FreeIntRegs, FreeVFPRegs);
3982 
3983   llvm::BasicBlock *MaybeRegBlock = CGF.createBasicBlock("vaarg.maybe_reg");
3984   llvm::BasicBlock *InRegBlock = CGF.createBasicBlock("vaarg.in_reg");
3985   llvm::BasicBlock *OnStackBlock = CGF.createBasicBlock("vaarg.on_stack");
3986   llvm::BasicBlock *ContBlock = CGF.createBasicBlock("vaarg.end");
3987 
3988   llvm::Value *reg_offs_p = 0, *reg_offs = 0;
3989   int reg_top_index;
3990   int RegSize;
3991   if (FreeIntRegs < 8) {
3992     assert(FreeVFPRegs == 8 && "Arguments never split between int & VFP regs");
3993     // 3 is the field number of __gr_offs
3994     reg_offs_p = CGF.Builder.CreateStructGEP(VAListAddr, 3, "gr_offs_p");
3995     reg_offs = CGF.Builder.CreateLoad(reg_offs_p, "gr_offs");
3996     reg_top_index = 1; // field number for __gr_top
3997     RegSize = 8 * (8 - FreeIntRegs);
3998   } else {
3999     assert(FreeVFPRegs < 8 && "Argument must go in VFP or int regs");
4000     // 4 is the field number of __vr_offs.
4001     reg_offs_p = CGF.Builder.CreateStructGEP(VAListAddr, 4, "vr_offs_p");
4002     reg_offs = CGF.Builder.CreateLoad(reg_offs_p, "vr_offs");
4003     reg_top_index = 2; // field number for __vr_top
4004     RegSize = 16 * (8 - FreeVFPRegs);
4005   }
4006 
4007   //=======================================
4008   // Find out where argument was passed
4009   //=======================================
4010 
4011   // If reg_offs >= 0 we're already using the stack for this type of
4012   // argument. We don't want to keep updating reg_offs (in case it overflows,
4013   // though anyone passing 2GB of arguments, each at most 16 bytes, deserves
4014   // whatever they get).
4015   llvm::Value *UsingStack = 0;
4016   UsingStack = CGF.Builder.CreateICmpSGE(reg_offs,
4017                                          llvm::ConstantInt::get(CGF.Int32Ty, 0));
4018 
4019   CGF.Builder.CreateCondBr(UsingStack, OnStackBlock, MaybeRegBlock);
4020 
4021   // Otherwise, at least some kind of argument could go in these registers, the
4022   // quesiton is whether this particular type is too big.
4023   CGF.EmitBlock(MaybeRegBlock);
4024 
4025   // Integer arguments may need to correct register alignment (for example a
4026   // "struct { __int128 a; };" gets passed in x_2N, x_{2N+1}). In this case we
4027   // align __gr_offs to calculate the potential address.
4028   if (FreeIntRegs < 8 && AI.isDirect() && getContext().getTypeAlign(Ty) > 64) {
4029     int Align = getContext().getTypeAlign(Ty) / 8;
4030 
4031     reg_offs = CGF.Builder.CreateAdd(reg_offs,
4032                                  llvm::ConstantInt::get(CGF.Int32Ty, Align - 1),
4033                                  "align_regoffs");
4034     reg_offs = CGF.Builder.CreateAnd(reg_offs,
4035                                     llvm::ConstantInt::get(CGF.Int32Ty, -Align),
4036                                     "aligned_regoffs");
4037   }
4038 
4039   // Update the gr_offs/vr_offs pointer for next call to va_arg on this va_list.
4040   llvm::Value *NewOffset = 0;
4041   NewOffset = CGF.Builder.CreateAdd(reg_offs,
4042                                     llvm::ConstantInt::get(CGF.Int32Ty, RegSize),
4043                                     "new_reg_offs");
4044   CGF.Builder.CreateStore(NewOffset, reg_offs_p);
4045 
4046   // Now we're in a position to decide whether this argument really was in
4047   // registers or not.
4048   llvm::Value *InRegs = 0;
4049   InRegs = CGF.Builder.CreateICmpSLE(NewOffset,
4050                                      llvm::ConstantInt::get(CGF.Int32Ty, 0),
4051                                      "inreg");
4052 
4053   CGF.Builder.CreateCondBr(InRegs, InRegBlock, OnStackBlock);
4054 
4055   //=======================================
4056   // Argument was in registers
4057   //=======================================
4058 
4059   // Now we emit the code for if the argument was originally passed in
4060   // registers. First start the appropriate block:
4061   CGF.EmitBlock(InRegBlock);
4062 
4063   llvm::Value *reg_top_p = 0, *reg_top = 0;
4064   reg_top_p = CGF.Builder.CreateStructGEP(VAListAddr, reg_top_index, "reg_top_p");
4065   reg_top = CGF.Builder.CreateLoad(reg_top_p, "reg_top");
4066   llvm::Value *BaseAddr = CGF.Builder.CreateGEP(reg_top, reg_offs);
4067   llvm::Value *RegAddr = 0;
4068   llvm::Type *MemTy = llvm::PointerType::getUnqual(CGF.ConvertTypeForMem(Ty));
4069 
4070   if (!AI.isDirect()) {
4071     // If it's been passed indirectly (actually a struct), whatever we find from
4072     // stored registers or on the stack will actually be a struct **.
4073     MemTy = llvm::PointerType::getUnqual(MemTy);
4074   }
4075 
4076   const Type *Base = 0;
4077   uint64_t NumMembers;
4078   if (isHomogeneousAggregate(Ty, Base, getContext(), &NumMembers)
4079       && NumMembers > 1) {
4080     // Homogeneous aggregates passed in registers will have their elements split
4081     // and stored 16-bytes apart regardless of size (they're notionally in qN,
4082     // qN+1, ...). We reload and store into a temporary local variable
4083     // contiguously.
4084     assert(AI.isDirect() && "Homogeneous aggregates should be passed directly");
4085     llvm::Type *BaseTy = CGF.ConvertType(QualType(Base, 0));
4086     llvm::Type *HFATy = llvm::ArrayType::get(BaseTy, NumMembers);
4087     llvm::Value *Tmp = CGF.CreateTempAlloca(HFATy);
4088 
4089     for (unsigned i = 0; i < NumMembers; ++i) {
4090       llvm::Value *BaseOffset = llvm::ConstantInt::get(CGF.Int32Ty, 16 * i);
4091       llvm::Value *LoadAddr = CGF.Builder.CreateGEP(BaseAddr, BaseOffset);
4092       LoadAddr = CGF.Builder.CreateBitCast(LoadAddr,
4093                                            llvm::PointerType::getUnqual(BaseTy));
4094       llvm::Value *StoreAddr = CGF.Builder.CreateStructGEP(Tmp, i);
4095 
4096       llvm::Value *Elem = CGF.Builder.CreateLoad(LoadAddr);
4097       CGF.Builder.CreateStore(Elem, StoreAddr);
4098     }
4099 
4100     RegAddr = CGF.Builder.CreateBitCast(Tmp, MemTy);
4101   } else {
4102     // Otherwise the object is contiguous in memory
4103     RegAddr = CGF.Builder.CreateBitCast(BaseAddr, MemTy);
4104   }
4105 
4106   CGF.EmitBranch(ContBlock);
4107 
4108   //=======================================
4109   // Argument was on the stack
4110   //=======================================
4111   CGF.EmitBlock(OnStackBlock);
4112 
4113   llvm::Value *stack_p = 0, *OnStackAddr = 0;
4114   stack_p = CGF.Builder.CreateStructGEP(VAListAddr, 0, "stack_p");
4115   OnStackAddr = CGF.Builder.CreateLoad(stack_p, "stack");
4116 
4117   // Again, stack arguments may need realigmnent. In this case both integer and
4118   // floating-point ones might be affected.
4119   if (AI.isDirect() && getContext().getTypeAlign(Ty) > 64) {
4120     int Align = getContext().getTypeAlign(Ty) / 8;
4121 
4122     OnStackAddr = CGF.Builder.CreatePtrToInt(OnStackAddr, CGF.Int64Ty);
4123 
4124     OnStackAddr = CGF.Builder.CreateAdd(OnStackAddr,
4125                                  llvm::ConstantInt::get(CGF.Int64Ty, Align - 1),
4126                                  "align_stack");
4127     OnStackAddr = CGF.Builder.CreateAnd(OnStackAddr,
4128                                     llvm::ConstantInt::get(CGF.Int64Ty, -Align),
4129                                     "align_stack");
4130 
4131     OnStackAddr = CGF.Builder.CreateIntToPtr(OnStackAddr, CGF.Int8PtrTy);
4132   }
4133 
4134   uint64_t StackSize;
4135   if (AI.isDirect())
4136     StackSize = getContext().getTypeSize(Ty) / 8;
4137   else
4138     StackSize = 8;
4139 
4140   // All stack slots are 8 bytes
4141   StackSize = llvm::RoundUpToAlignment(StackSize, 8);
4142 
4143   llvm::Value *StackSizeC = llvm::ConstantInt::get(CGF.Int32Ty, StackSize);
4144   llvm::Value *NewStack = CGF.Builder.CreateGEP(OnStackAddr, StackSizeC,
4145                                                 "new_stack");
4146 
4147   // Write the new value of __stack for the next call to va_arg
4148   CGF.Builder.CreateStore(NewStack, stack_p);
4149 
4150   OnStackAddr = CGF.Builder.CreateBitCast(OnStackAddr, MemTy);
4151 
4152   CGF.EmitBranch(ContBlock);
4153 
4154   //=======================================
4155   // Tidy up
4156   //=======================================
4157   CGF.EmitBlock(ContBlock);
4158 
4159   llvm::PHINode *ResAddr = CGF.Builder.CreatePHI(MemTy, 2, "vaarg.addr");
4160   ResAddr->addIncoming(RegAddr, InRegBlock);
4161   ResAddr->addIncoming(OnStackAddr, OnStackBlock);
4162 
4163   if (AI.isDirect())
4164     return ResAddr;
4165 
4166   return CGF.Builder.CreateLoad(ResAddr, "vaarg.addr");
4167 }
4168 
4169 //===----------------------------------------------------------------------===//
4170 // NVPTX ABI Implementation
4171 //===----------------------------------------------------------------------===//
4172 
4173 namespace {
4174 
4175 class NVPTXABIInfo : public ABIInfo {
4176 public:
4177   NVPTXABIInfo(CodeGenTypes &CGT) : ABIInfo(CGT) {}
4178 
4179   ABIArgInfo classifyReturnType(QualType RetTy) const;
4180   ABIArgInfo classifyArgumentType(QualType Ty) const;
4181 
4182   virtual void computeInfo(CGFunctionInfo &FI) const;
4183   virtual llvm::Value *EmitVAArg(llvm::Value *VAListAddr, QualType Ty,
4184                                  CodeGenFunction &CFG) const;
4185 };
4186 
4187 class NVPTXTargetCodeGenInfo : public TargetCodeGenInfo {
4188 public:
4189   NVPTXTargetCodeGenInfo(CodeGenTypes &CGT)
4190     : TargetCodeGenInfo(new NVPTXABIInfo(CGT)) {}
4191 
4192   virtual void SetTargetAttributes(const Decl *D, llvm::GlobalValue *GV,
4193                                    CodeGen::CodeGenModule &M) const;
4194 private:
4195   static void addKernelMetadata(llvm::Function *F);
4196 };
4197 
4198 ABIArgInfo NVPTXABIInfo::classifyReturnType(QualType RetTy) const {
4199   if (RetTy->isVoidType())
4200     return ABIArgInfo::getIgnore();
4201   if (isAggregateTypeForABI(RetTy))
4202     return ABIArgInfo::getIndirect(0);
4203   return ABIArgInfo::getDirect();
4204 }
4205 
4206 ABIArgInfo NVPTXABIInfo::classifyArgumentType(QualType Ty) const {
4207   if (isAggregateTypeForABI(Ty))
4208     return ABIArgInfo::getIndirect(0);
4209 
4210   return ABIArgInfo::getDirect();
4211 }
4212 
4213 void NVPTXABIInfo::computeInfo(CGFunctionInfo &FI) const {
4214   FI.getReturnInfo() = classifyReturnType(FI.getReturnType());
4215   for (CGFunctionInfo::arg_iterator it = FI.arg_begin(), ie = FI.arg_end();
4216        it != ie; ++it)
4217     it->info = classifyArgumentType(it->type);
4218 
4219   // Always honor user-specified calling convention.
4220   if (FI.getCallingConvention() != llvm::CallingConv::C)
4221     return;
4222 
4223   FI.setEffectiveCallingConvention(getRuntimeCC());
4224 }
4225 
4226 llvm::Value *NVPTXABIInfo::EmitVAArg(llvm::Value *VAListAddr, QualType Ty,
4227                                      CodeGenFunction &CFG) const {
4228   llvm_unreachable("NVPTX does not support varargs");
4229 }
4230 
4231 void NVPTXTargetCodeGenInfo::
4232 SetTargetAttributes(const Decl *D, llvm::GlobalValue *GV,
4233                     CodeGen::CodeGenModule &M) const{
4234   const FunctionDecl *FD = dyn_cast<FunctionDecl>(D);
4235   if (!FD) return;
4236 
4237   llvm::Function *F = cast<llvm::Function>(GV);
4238 
4239   // Perform special handling in OpenCL mode
4240   if (M.getLangOpts().OpenCL) {
4241     // Use OpenCL function attributes to check for kernel functions
4242     // By default, all functions are device functions
4243     if (FD->hasAttr<OpenCLKernelAttr>()) {
4244       // OpenCL __kernel functions get kernel metadata
4245       addKernelMetadata(F);
4246       // And kernel functions are not subject to inlining
4247       F->addFnAttr(llvm::Attribute::NoInline);
4248     }
4249   }
4250 
4251   // Perform special handling in CUDA mode.
4252   if (M.getLangOpts().CUDA) {
4253     // CUDA __global__ functions get a kernel metadata entry.  Since
4254     // __global__ functions cannot be called from the device, we do not
4255     // need to set the noinline attribute.
4256     if (FD->getAttr<CUDAGlobalAttr>())
4257       addKernelMetadata(F);
4258   }
4259 }
4260 
4261 void NVPTXTargetCodeGenInfo::addKernelMetadata(llvm::Function *F) {
4262   llvm::Module *M = F->getParent();
4263   llvm::LLVMContext &Ctx = M->getContext();
4264 
4265   // Get "nvvm.annotations" metadata node
4266   llvm::NamedMDNode *MD = M->getOrInsertNamedMetadata("nvvm.annotations");
4267 
4268   // Create !{<func-ref>, metadata !"kernel", i32 1} node
4269   llvm::SmallVector<llvm::Value *, 3> MDVals;
4270   MDVals.push_back(F);
4271   MDVals.push_back(llvm::MDString::get(Ctx, "kernel"));
4272   MDVals.push_back(llvm::ConstantInt::get(llvm::Type::getInt32Ty(Ctx), 1));
4273 
4274   // Append metadata to nvvm.annotations
4275   MD->addOperand(llvm::MDNode::get(Ctx, MDVals));
4276 }
4277 
4278 }
4279 
4280 //===----------------------------------------------------------------------===//
4281 // SystemZ ABI Implementation
4282 //===----------------------------------------------------------------------===//
4283 
4284 namespace {
4285 
4286 class SystemZABIInfo : public ABIInfo {
4287 public:
4288   SystemZABIInfo(CodeGenTypes &CGT) : ABIInfo(CGT) {}
4289 
4290   bool isPromotableIntegerType(QualType Ty) const;
4291   bool isCompoundType(QualType Ty) const;
4292   bool isFPArgumentType(QualType Ty) const;
4293 
4294   ABIArgInfo classifyReturnType(QualType RetTy) const;
4295   ABIArgInfo classifyArgumentType(QualType ArgTy) const;
4296 
4297   virtual void computeInfo(CGFunctionInfo &FI) const {
4298     FI.getReturnInfo() = classifyReturnType(FI.getReturnType());
4299     for (CGFunctionInfo::arg_iterator it = FI.arg_begin(), ie = FI.arg_end();
4300          it != ie; ++it)
4301       it->info = classifyArgumentType(it->type);
4302   }
4303 
4304   virtual llvm::Value *EmitVAArg(llvm::Value *VAListAddr, QualType Ty,
4305                                  CodeGenFunction &CGF) const;
4306 };
4307 
4308 class SystemZTargetCodeGenInfo : public TargetCodeGenInfo {
4309 public:
4310   SystemZTargetCodeGenInfo(CodeGenTypes &CGT)
4311     : TargetCodeGenInfo(new SystemZABIInfo(CGT)) {}
4312 };
4313 
4314 }
4315 
4316 bool SystemZABIInfo::isPromotableIntegerType(QualType Ty) const {
4317   // Treat an enum type as its underlying type.
4318   if (const EnumType *EnumTy = Ty->getAs<EnumType>())
4319     Ty = EnumTy->getDecl()->getIntegerType();
4320 
4321   // Promotable integer types are required to be promoted by the ABI.
4322   if (Ty->isPromotableIntegerType())
4323     return true;
4324 
4325   // 32-bit values must also be promoted.
4326   if (const BuiltinType *BT = Ty->getAs<BuiltinType>())
4327     switch (BT->getKind()) {
4328     case BuiltinType::Int:
4329     case BuiltinType::UInt:
4330       return true;
4331     default:
4332       return false;
4333     }
4334   return false;
4335 }
4336 
4337 bool SystemZABIInfo::isCompoundType(QualType Ty) const {
4338   return Ty->isAnyComplexType() || isAggregateTypeForABI(Ty);
4339 }
4340 
4341 bool SystemZABIInfo::isFPArgumentType(QualType Ty) const {
4342   if (const BuiltinType *BT = Ty->getAs<BuiltinType>())
4343     switch (BT->getKind()) {
4344     case BuiltinType::Float:
4345     case BuiltinType::Double:
4346       return true;
4347     default:
4348       return false;
4349     }
4350 
4351   if (const RecordType *RT = Ty->getAsStructureType()) {
4352     const RecordDecl *RD = RT->getDecl();
4353     bool Found = false;
4354 
4355     // If this is a C++ record, check the bases first.
4356     if (const CXXRecordDecl *CXXRD = dyn_cast<CXXRecordDecl>(RD))
4357       for (CXXRecordDecl::base_class_const_iterator I = CXXRD->bases_begin(),
4358              E = CXXRD->bases_end(); I != E; ++I) {
4359         QualType Base = I->getType();
4360 
4361         // Empty bases don't affect things either way.
4362         if (isEmptyRecord(getContext(), Base, true))
4363           continue;
4364 
4365         if (Found)
4366           return false;
4367         Found = isFPArgumentType(Base);
4368         if (!Found)
4369           return false;
4370       }
4371 
4372     // Check the fields.
4373     for (RecordDecl::field_iterator I = RD->field_begin(),
4374            E = RD->field_end(); I != E; ++I) {
4375       const FieldDecl *FD = *I;
4376 
4377       // Empty bitfields don't affect things either way.
4378       // Unlike isSingleElementStruct(), empty structure and array fields
4379       // do count.  So do anonymous bitfields that aren't zero-sized.
4380       if (FD->isBitField() && FD->getBitWidthValue(getContext()) == 0)
4381         return true;
4382 
4383       // Unlike isSingleElementStruct(), arrays do not count.
4384       // Nested isFPArgumentType structures still do though.
4385       if (Found)
4386         return false;
4387       Found = isFPArgumentType(FD->getType());
4388       if (!Found)
4389         return false;
4390     }
4391 
4392     // Unlike isSingleElementStruct(), trailing padding is allowed.
4393     // An 8-byte aligned struct s { float f; } is passed as a double.
4394     return Found;
4395   }
4396 
4397   return false;
4398 }
4399 
4400 llvm::Value *SystemZABIInfo::EmitVAArg(llvm::Value *VAListAddr, QualType Ty,
4401                                        CodeGenFunction &CGF) const {
4402   // Assume that va_list type is correct; should be pointer to LLVM type:
4403   // struct {
4404   //   i64 __gpr;
4405   //   i64 __fpr;
4406   //   i8 *__overflow_arg_area;
4407   //   i8 *__reg_save_area;
4408   // };
4409 
4410   // Every argument occupies 8 bytes and is passed by preference in either
4411   // GPRs or FPRs.
4412   Ty = CGF.getContext().getCanonicalType(Ty);
4413   ABIArgInfo AI = classifyArgumentType(Ty);
4414   bool InFPRs = isFPArgumentType(Ty);
4415 
4416   llvm::Type *APTy = llvm::PointerType::getUnqual(CGF.ConvertTypeForMem(Ty));
4417   bool IsIndirect = AI.isIndirect();
4418   unsigned UnpaddedBitSize;
4419   if (IsIndirect) {
4420     APTy = llvm::PointerType::getUnqual(APTy);
4421     UnpaddedBitSize = 64;
4422   } else
4423     UnpaddedBitSize = getContext().getTypeSize(Ty);
4424   unsigned PaddedBitSize = 64;
4425   assert((UnpaddedBitSize <= PaddedBitSize) && "Invalid argument size.");
4426 
4427   unsigned PaddedSize = PaddedBitSize / 8;
4428   unsigned Padding = (PaddedBitSize - UnpaddedBitSize) / 8;
4429 
4430   unsigned MaxRegs, RegCountField, RegSaveIndex, RegPadding;
4431   if (InFPRs) {
4432     MaxRegs = 4; // Maximum of 4 FPR arguments
4433     RegCountField = 1; // __fpr
4434     RegSaveIndex = 16; // save offset for f0
4435     RegPadding = 0; // floats are passed in the high bits of an FPR
4436   } else {
4437     MaxRegs = 5; // Maximum of 5 GPR arguments
4438     RegCountField = 0; // __gpr
4439     RegSaveIndex = 2; // save offset for r2
4440     RegPadding = Padding; // values are passed in the low bits of a GPR
4441   }
4442 
4443   llvm::Value *RegCountPtr =
4444     CGF.Builder.CreateStructGEP(VAListAddr, RegCountField, "reg_count_ptr");
4445   llvm::Value *RegCount = CGF.Builder.CreateLoad(RegCountPtr, "reg_count");
4446   llvm::Type *IndexTy = RegCount->getType();
4447   llvm::Value *MaxRegsV = llvm::ConstantInt::get(IndexTy, MaxRegs);
4448   llvm::Value *InRegs = CGF.Builder.CreateICmpULT(RegCount, MaxRegsV,
4449 						  "fits_in_regs");
4450 
4451   llvm::BasicBlock *InRegBlock = CGF.createBasicBlock("vaarg.in_reg");
4452   llvm::BasicBlock *InMemBlock = CGF.createBasicBlock("vaarg.in_mem");
4453   llvm::BasicBlock *ContBlock = CGF.createBasicBlock("vaarg.end");
4454   CGF.Builder.CreateCondBr(InRegs, InRegBlock, InMemBlock);
4455 
4456   // Emit code to load the value if it was passed in registers.
4457   CGF.EmitBlock(InRegBlock);
4458 
4459   // Work out the address of an argument register.
4460   llvm::Value *PaddedSizeV = llvm::ConstantInt::get(IndexTy, PaddedSize);
4461   llvm::Value *ScaledRegCount =
4462     CGF.Builder.CreateMul(RegCount, PaddedSizeV, "scaled_reg_count");
4463   llvm::Value *RegBase =
4464     llvm::ConstantInt::get(IndexTy, RegSaveIndex * PaddedSize + RegPadding);
4465   llvm::Value *RegOffset =
4466     CGF.Builder.CreateAdd(ScaledRegCount, RegBase, "reg_offset");
4467   llvm::Value *RegSaveAreaPtr =
4468     CGF.Builder.CreateStructGEP(VAListAddr, 3, "reg_save_area_ptr");
4469   llvm::Value *RegSaveArea =
4470     CGF.Builder.CreateLoad(RegSaveAreaPtr, "reg_save_area");
4471   llvm::Value *RawRegAddr =
4472     CGF.Builder.CreateGEP(RegSaveArea, RegOffset, "raw_reg_addr");
4473   llvm::Value *RegAddr =
4474     CGF.Builder.CreateBitCast(RawRegAddr, APTy, "reg_addr");
4475 
4476   // Update the register count
4477   llvm::Value *One = llvm::ConstantInt::get(IndexTy, 1);
4478   llvm::Value *NewRegCount =
4479     CGF.Builder.CreateAdd(RegCount, One, "reg_count");
4480   CGF.Builder.CreateStore(NewRegCount, RegCountPtr);
4481   CGF.EmitBranch(ContBlock);
4482 
4483   // Emit code to load the value if it was passed in memory.
4484   CGF.EmitBlock(InMemBlock);
4485 
4486   // Work out the address of a stack argument.
4487   llvm::Value *OverflowArgAreaPtr =
4488     CGF.Builder.CreateStructGEP(VAListAddr, 2, "overflow_arg_area_ptr");
4489   llvm::Value *OverflowArgArea =
4490     CGF.Builder.CreateLoad(OverflowArgAreaPtr, "overflow_arg_area");
4491   llvm::Value *PaddingV = llvm::ConstantInt::get(IndexTy, Padding);
4492   llvm::Value *RawMemAddr =
4493     CGF.Builder.CreateGEP(OverflowArgArea, PaddingV, "raw_mem_addr");
4494   llvm::Value *MemAddr =
4495     CGF.Builder.CreateBitCast(RawMemAddr, APTy, "mem_addr");
4496 
4497   // Update overflow_arg_area_ptr pointer
4498   llvm::Value *NewOverflowArgArea =
4499     CGF.Builder.CreateGEP(OverflowArgArea, PaddedSizeV, "overflow_arg_area");
4500   CGF.Builder.CreateStore(NewOverflowArgArea, OverflowArgAreaPtr);
4501   CGF.EmitBranch(ContBlock);
4502 
4503   // Return the appropriate result.
4504   CGF.EmitBlock(ContBlock);
4505   llvm::PHINode *ResAddr = CGF.Builder.CreatePHI(APTy, 2, "va_arg.addr");
4506   ResAddr->addIncoming(RegAddr, InRegBlock);
4507   ResAddr->addIncoming(MemAddr, InMemBlock);
4508 
4509   if (IsIndirect)
4510     return CGF.Builder.CreateLoad(ResAddr, "indirect_arg");
4511 
4512   return ResAddr;
4513 }
4514 
4515 bool X86_32TargetCodeGenInfo::isStructReturnInRegABI(
4516     const llvm::Triple &Triple, const CodeGenOptions &Opts) {
4517   assert(Triple.getArch() == llvm::Triple::x86);
4518 
4519   switch (Opts.getStructReturnConvention()) {
4520   case CodeGenOptions::SRCK_Default:
4521     break;
4522   case CodeGenOptions::SRCK_OnStack:  // -fpcc-struct-return
4523     return false;
4524   case CodeGenOptions::SRCK_InRegs:  // -freg-struct-return
4525     return true;
4526   }
4527 
4528   if (Triple.isOSDarwin())
4529     return true;
4530 
4531   switch (Triple.getOS()) {
4532   case llvm::Triple::Cygwin:
4533   case llvm::Triple::MinGW32:
4534   case llvm::Triple::AuroraUX:
4535   case llvm::Triple::DragonFly:
4536   case llvm::Triple::FreeBSD:
4537   case llvm::Triple::OpenBSD:
4538   case llvm::Triple::Bitrig:
4539   case llvm::Triple::Win32:
4540     return true;
4541   default:
4542     return false;
4543   }
4544 }
4545 
4546 ABIArgInfo SystemZABIInfo::classifyReturnType(QualType RetTy) const {
4547   if (RetTy->isVoidType())
4548     return ABIArgInfo::getIgnore();
4549   if (isCompoundType(RetTy) || getContext().getTypeSize(RetTy) > 64)
4550     return ABIArgInfo::getIndirect(0);
4551   return (isPromotableIntegerType(RetTy) ?
4552           ABIArgInfo::getExtend() : ABIArgInfo::getDirect());
4553 }
4554 
4555 ABIArgInfo SystemZABIInfo::classifyArgumentType(QualType Ty) const {
4556   // Handle the generic C++ ABI.
4557   if (CGCXXABI::RecordArgABI RAA = getRecordArgABI(Ty, getCXXABI()))
4558     return ABIArgInfo::getIndirect(0, RAA == CGCXXABI::RAA_DirectInMemory);
4559 
4560   // Integers and enums are extended to full register width.
4561   if (isPromotableIntegerType(Ty))
4562     return ABIArgInfo::getExtend();
4563 
4564   // Values that are not 1, 2, 4 or 8 bytes in size are passed indirectly.
4565   uint64_t Size = getContext().getTypeSize(Ty);
4566   if (Size != 8 && Size != 16 && Size != 32 && Size != 64)
4567     return ABIArgInfo::getIndirect(0);
4568 
4569   // Handle small structures.
4570   if (const RecordType *RT = Ty->getAs<RecordType>()) {
4571     // Structures with flexible arrays have variable length, so really
4572     // fail the size test above.
4573     const RecordDecl *RD = RT->getDecl();
4574     if (RD->hasFlexibleArrayMember())
4575       return ABIArgInfo::getIndirect(0);
4576 
4577     // The structure is passed as an unextended integer, a float, or a double.
4578     llvm::Type *PassTy;
4579     if (isFPArgumentType(Ty)) {
4580       assert(Size == 32 || Size == 64);
4581       if (Size == 32)
4582         PassTy = llvm::Type::getFloatTy(getVMContext());
4583       else
4584         PassTy = llvm::Type::getDoubleTy(getVMContext());
4585     } else
4586       PassTy = llvm::IntegerType::get(getVMContext(), Size);
4587     return ABIArgInfo::getDirect(PassTy);
4588   }
4589 
4590   // Non-structure compounds are passed indirectly.
4591   if (isCompoundType(Ty))
4592     return ABIArgInfo::getIndirect(0);
4593 
4594   return ABIArgInfo::getDirect(0);
4595 }
4596 
4597 //===----------------------------------------------------------------------===//
4598 // MSP430 ABI Implementation
4599 //===----------------------------------------------------------------------===//
4600 
4601 namespace {
4602 
4603 class MSP430TargetCodeGenInfo : public TargetCodeGenInfo {
4604 public:
4605   MSP430TargetCodeGenInfo(CodeGenTypes &CGT)
4606     : TargetCodeGenInfo(new DefaultABIInfo(CGT)) {}
4607   void SetTargetAttributes(const Decl *D, llvm::GlobalValue *GV,
4608                            CodeGen::CodeGenModule &M) const;
4609 };
4610 
4611 }
4612 
4613 void MSP430TargetCodeGenInfo::SetTargetAttributes(const Decl *D,
4614                                                   llvm::GlobalValue *GV,
4615                                              CodeGen::CodeGenModule &M) const {
4616   if (const FunctionDecl *FD = dyn_cast<FunctionDecl>(D)) {
4617     if (const MSP430InterruptAttr *attr = FD->getAttr<MSP430InterruptAttr>()) {
4618       // Handle 'interrupt' attribute:
4619       llvm::Function *F = cast<llvm::Function>(GV);
4620 
4621       // Step 1: Set ISR calling convention.
4622       F->setCallingConv(llvm::CallingConv::MSP430_INTR);
4623 
4624       // Step 2: Add attributes goodness.
4625       F->addFnAttr(llvm::Attribute::NoInline);
4626 
4627       // Step 3: Emit ISR vector alias.
4628       unsigned Num = attr->getNumber() / 2;
4629       new llvm::GlobalAlias(GV->getType(), llvm::Function::ExternalLinkage,
4630                             "__isr_" + Twine(Num),
4631                             GV, &M.getModule());
4632     }
4633   }
4634 }
4635 
4636 //===----------------------------------------------------------------------===//
4637 // MIPS ABI Implementation.  This works for both little-endian and
4638 // big-endian variants.
4639 //===----------------------------------------------------------------------===//
4640 
4641 namespace {
4642 class MipsABIInfo : public ABIInfo {
4643   bool IsO32;
4644   unsigned MinABIStackAlignInBytes, StackAlignInBytes;
4645   void CoerceToIntArgs(uint64_t TySize,
4646                        SmallVectorImpl<llvm::Type *> &ArgList) const;
4647   llvm::Type* HandleAggregates(QualType Ty, uint64_t TySize) const;
4648   llvm::Type* returnAggregateInRegs(QualType RetTy, uint64_t Size) const;
4649   llvm::Type* getPaddingType(uint64_t Align, uint64_t Offset) const;
4650 public:
4651   MipsABIInfo(CodeGenTypes &CGT, bool _IsO32, bool HasFP64) :
4652     ABIInfo(CGT), IsO32(_IsO32), MinABIStackAlignInBytes(IsO32 ? 4 : 8),
4653     StackAlignInBytes(IsO32 && !HasFP64 ? 8 : 16) {}
4654 
4655   ABIArgInfo classifyReturnType(QualType RetTy) const;
4656   ABIArgInfo classifyArgumentType(QualType RetTy, uint64_t &Offset) const;
4657   virtual void computeInfo(CGFunctionInfo &FI) const;
4658   virtual llvm::Value *EmitVAArg(llvm::Value *VAListAddr, QualType Ty,
4659                                  CodeGenFunction &CGF) const;
4660 };
4661 
4662 class MIPSTargetCodeGenInfo : public TargetCodeGenInfo {
4663   unsigned SizeOfUnwindException;
4664 public:
4665   MIPSTargetCodeGenInfo(CodeGenTypes &CGT, bool IsO32, const TargetInfo &Info)
4666     : TargetCodeGenInfo(new MipsABIInfo(CGT, IsO32, Info.hasFeature("fp64"))),
4667       SizeOfUnwindException(IsO32 ? 24 : 32) {}
4668 
4669   int getDwarfEHStackPointer(CodeGen::CodeGenModule &CGM) const {
4670     return 29;
4671   }
4672 
4673   void SetTargetAttributes(const Decl *D, llvm::GlobalValue *GV,
4674                            CodeGen::CodeGenModule &CGM) const {
4675     const FunctionDecl *FD = dyn_cast<FunctionDecl>(D);
4676     if (!FD) return;
4677     llvm::Function *Fn = cast<llvm::Function>(GV);
4678     if (FD->hasAttr<Mips16Attr>()) {
4679       Fn->addFnAttr("mips16");
4680     }
4681     else if (FD->hasAttr<NoMips16Attr>()) {
4682       Fn->addFnAttr("nomips16");
4683     }
4684   }
4685 
4686   bool initDwarfEHRegSizeTable(CodeGen::CodeGenFunction &CGF,
4687                                llvm::Value *Address) const;
4688 
4689   unsigned getSizeOfUnwindException() const {
4690     return SizeOfUnwindException;
4691   }
4692 };
4693 }
4694 
4695 void MipsABIInfo::CoerceToIntArgs(uint64_t TySize,
4696                                   SmallVectorImpl<llvm::Type *> &ArgList) const {
4697   llvm::IntegerType *IntTy =
4698     llvm::IntegerType::get(getVMContext(), MinABIStackAlignInBytes * 8);
4699 
4700   // Add (TySize / MinABIStackAlignInBytes) args of IntTy.
4701   for (unsigned N = TySize / (MinABIStackAlignInBytes * 8); N; --N)
4702     ArgList.push_back(IntTy);
4703 
4704   // If necessary, add one more integer type to ArgList.
4705   unsigned R = TySize % (MinABIStackAlignInBytes * 8);
4706 
4707   if (R)
4708     ArgList.push_back(llvm::IntegerType::get(getVMContext(), R));
4709 }
4710 
4711 // In N32/64, an aligned double precision floating point field is passed in
4712 // a register.
4713 llvm::Type* MipsABIInfo::HandleAggregates(QualType Ty, uint64_t TySize) const {
4714   SmallVector<llvm::Type*, 8> ArgList, IntArgList;
4715 
4716   if (IsO32) {
4717     CoerceToIntArgs(TySize, ArgList);
4718     return llvm::StructType::get(getVMContext(), ArgList);
4719   }
4720 
4721   if (Ty->isComplexType())
4722     return CGT.ConvertType(Ty);
4723 
4724   const RecordType *RT = Ty->getAs<RecordType>();
4725 
4726   // Unions/vectors are passed in integer registers.
4727   if (!RT || !RT->isStructureOrClassType()) {
4728     CoerceToIntArgs(TySize, ArgList);
4729     return llvm::StructType::get(getVMContext(), ArgList);
4730   }
4731 
4732   const RecordDecl *RD = RT->getDecl();
4733   const ASTRecordLayout &Layout = getContext().getASTRecordLayout(RD);
4734   assert(!(TySize % 8) && "Size of structure must be multiple of 8.");
4735 
4736   uint64_t LastOffset = 0;
4737   unsigned idx = 0;
4738   llvm::IntegerType *I64 = llvm::IntegerType::get(getVMContext(), 64);
4739 
4740   // Iterate over fields in the struct/class and check if there are any aligned
4741   // double fields.
4742   for (RecordDecl::field_iterator i = RD->field_begin(), e = RD->field_end();
4743        i != e; ++i, ++idx) {
4744     const QualType Ty = i->getType();
4745     const BuiltinType *BT = Ty->getAs<BuiltinType>();
4746 
4747     if (!BT || BT->getKind() != BuiltinType::Double)
4748       continue;
4749 
4750     uint64_t Offset = Layout.getFieldOffset(idx);
4751     if (Offset % 64) // Ignore doubles that are not aligned.
4752       continue;
4753 
4754     // Add ((Offset - LastOffset) / 64) args of type i64.
4755     for (unsigned j = (Offset - LastOffset) / 64; j > 0; --j)
4756       ArgList.push_back(I64);
4757 
4758     // Add double type.
4759     ArgList.push_back(llvm::Type::getDoubleTy(getVMContext()));
4760     LastOffset = Offset + 64;
4761   }
4762 
4763   CoerceToIntArgs(TySize - LastOffset, IntArgList);
4764   ArgList.append(IntArgList.begin(), IntArgList.end());
4765 
4766   return llvm::StructType::get(getVMContext(), ArgList);
4767 }
4768 
4769 llvm::Type *MipsABIInfo::getPaddingType(uint64_t OrigOffset,
4770                                         uint64_t Offset) const {
4771   if (OrigOffset + MinABIStackAlignInBytes > Offset)
4772     return 0;
4773 
4774   return llvm::IntegerType::get(getVMContext(), (Offset - OrigOffset) * 8);
4775 }
4776 
4777 ABIArgInfo
4778 MipsABIInfo::classifyArgumentType(QualType Ty, uint64_t &Offset) const {
4779   uint64_t OrigOffset = Offset;
4780   uint64_t TySize = getContext().getTypeSize(Ty);
4781   uint64_t Align = getContext().getTypeAlign(Ty) / 8;
4782 
4783   Align = std::min(std::max(Align, (uint64_t)MinABIStackAlignInBytes),
4784                    (uint64_t)StackAlignInBytes);
4785   unsigned CurrOffset = llvm::RoundUpToAlignment(Offset, Align);
4786   Offset = CurrOffset + llvm::RoundUpToAlignment(TySize, Align * 8) / 8;
4787 
4788   if (isAggregateTypeForABI(Ty) || Ty->isVectorType()) {
4789     // Ignore empty aggregates.
4790     if (TySize == 0)
4791       return ABIArgInfo::getIgnore();
4792 
4793     if (CGCXXABI::RecordArgABI RAA = getRecordArgABI(Ty, getCXXABI())) {
4794       Offset = OrigOffset + MinABIStackAlignInBytes;
4795       return ABIArgInfo::getIndirect(0, RAA == CGCXXABI::RAA_DirectInMemory);
4796     }
4797 
4798     // If we have reached here, aggregates are passed directly by coercing to
4799     // another structure type. Padding is inserted if the offset of the
4800     // aggregate is unaligned.
4801     return ABIArgInfo::getDirect(HandleAggregates(Ty, TySize), 0,
4802                                  getPaddingType(OrigOffset, CurrOffset));
4803   }
4804 
4805   // Treat an enum type as its underlying type.
4806   if (const EnumType *EnumTy = Ty->getAs<EnumType>())
4807     Ty = EnumTy->getDecl()->getIntegerType();
4808 
4809   if (Ty->isPromotableIntegerType())
4810     return ABIArgInfo::getExtend();
4811 
4812   return ABIArgInfo::getDirect(
4813       0, 0, IsO32 ? 0 : getPaddingType(OrigOffset, CurrOffset));
4814 }
4815 
4816 llvm::Type*
4817 MipsABIInfo::returnAggregateInRegs(QualType RetTy, uint64_t Size) const {
4818   const RecordType *RT = RetTy->getAs<RecordType>();
4819   SmallVector<llvm::Type*, 8> RTList;
4820 
4821   if (RT && RT->isStructureOrClassType()) {
4822     const RecordDecl *RD = RT->getDecl();
4823     const ASTRecordLayout &Layout = getContext().getASTRecordLayout(RD);
4824     unsigned FieldCnt = Layout.getFieldCount();
4825 
4826     // N32/64 returns struct/classes in floating point registers if the
4827     // following conditions are met:
4828     // 1. The size of the struct/class is no larger than 128-bit.
4829     // 2. The struct/class has one or two fields all of which are floating
4830     //    point types.
4831     // 3. The offset of the first field is zero (this follows what gcc does).
4832     //
4833     // Any other composite results are returned in integer registers.
4834     //
4835     if (FieldCnt && (FieldCnt <= 2) && !Layout.getFieldOffset(0)) {
4836       RecordDecl::field_iterator b = RD->field_begin(), e = RD->field_end();
4837       for (; b != e; ++b) {
4838         const BuiltinType *BT = b->getType()->getAs<BuiltinType>();
4839 
4840         if (!BT || !BT->isFloatingPoint())
4841           break;
4842 
4843         RTList.push_back(CGT.ConvertType(b->getType()));
4844       }
4845 
4846       if (b == e)
4847         return llvm::StructType::get(getVMContext(), RTList,
4848                                      RD->hasAttr<PackedAttr>());
4849 
4850       RTList.clear();
4851     }
4852   }
4853 
4854   CoerceToIntArgs(Size, RTList);
4855   return llvm::StructType::get(getVMContext(), RTList);
4856 }
4857 
4858 ABIArgInfo MipsABIInfo::classifyReturnType(QualType RetTy) const {
4859   uint64_t Size = getContext().getTypeSize(RetTy);
4860 
4861   if (RetTy->isVoidType() || Size == 0)
4862     return ABIArgInfo::getIgnore();
4863 
4864   if (isAggregateTypeForABI(RetTy) || RetTy->isVectorType()) {
4865     if (isRecordReturnIndirect(RetTy, getCXXABI()))
4866       return ABIArgInfo::getIndirect(0);
4867 
4868     if (Size <= 128) {
4869       if (RetTy->isAnyComplexType())
4870         return ABIArgInfo::getDirect();
4871 
4872       // O32 returns integer vectors in registers.
4873       if (IsO32 && RetTy->isVectorType() && !RetTy->hasFloatingRepresentation())
4874         return ABIArgInfo::getDirect(returnAggregateInRegs(RetTy, Size));
4875 
4876       if (!IsO32)
4877         return ABIArgInfo::getDirect(returnAggregateInRegs(RetTy, Size));
4878     }
4879 
4880     return ABIArgInfo::getIndirect(0);
4881   }
4882 
4883   // Treat an enum type as its underlying type.
4884   if (const EnumType *EnumTy = RetTy->getAs<EnumType>())
4885     RetTy = EnumTy->getDecl()->getIntegerType();
4886 
4887   return (RetTy->isPromotableIntegerType() ?
4888           ABIArgInfo::getExtend() : ABIArgInfo::getDirect());
4889 }
4890 
4891 void MipsABIInfo::computeInfo(CGFunctionInfo &FI) const {
4892   ABIArgInfo &RetInfo = FI.getReturnInfo();
4893   RetInfo = classifyReturnType(FI.getReturnType());
4894 
4895   // Check if a pointer to an aggregate is passed as a hidden argument.
4896   uint64_t Offset = RetInfo.isIndirect() ? MinABIStackAlignInBytes : 0;
4897 
4898   for (CGFunctionInfo::arg_iterator it = FI.arg_begin(), ie = FI.arg_end();
4899        it != ie; ++it)
4900     it->info = classifyArgumentType(it->type, Offset);
4901 }
4902 
4903 llvm::Value* MipsABIInfo::EmitVAArg(llvm::Value *VAListAddr, QualType Ty,
4904                                     CodeGenFunction &CGF) const {
4905   llvm::Type *BP = CGF.Int8PtrTy;
4906   llvm::Type *BPP = CGF.Int8PtrPtrTy;
4907 
4908   CGBuilderTy &Builder = CGF.Builder;
4909   llvm::Value *VAListAddrAsBPP = Builder.CreateBitCast(VAListAddr, BPP, "ap");
4910   llvm::Value *Addr = Builder.CreateLoad(VAListAddrAsBPP, "ap.cur");
4911   int64_t TypeAlign = getContext().getTypeAlign(Ty) / 8;
4912   llvm::Type *PTy = llvm::PointerType::getUnqual(CGF.ConvertType(Ty));
4913   llvm::Value *AddrTyped;
4914   unsigned PtrWidth = getTarget().getPointerWidth(0);
4915   llvm::IntegerType *IntTy = (PtrWidth == 32) ? CGF.Int32Ty : CGF.Int64Ty;
4916 
4917   if (TypeAlign > MinABIStackAlignInBytes) {
4918     llvm::Value *AddrAsInt = CGF.Builder.CreatePtrToInt(Addr, IntTy);
4919     llvm::Value *Inc = llvm::ConstantInt::get(IntTy, TypeAlign - 1);
4920     llvm::Value *Mask = llvm::ConstantInt::get(IntTy, -TypeAlign);
4921     llvm::Value *Add = CGF.Builder.CreateAdd(AddrAsInt, Inc);
4922     llvm::Value *And = CGF.Builder.CreateAnd(Add, Mask);
4923     AddrTyped = CGF.Builder.CreateIntToPtr(And, PTy);
4924   }
4925   else
4926     AddrTyped = Builder.CreateBitCast(Addr, PTy);
4927 
4928   llvm::Value *AlignedAddr = Builder.CreateBitCast(AddrTyped, BP);
4929   TypeAlign = std::max((unsigned)TypeAlign, MinABIStackAlignInBytes);
4930   uint64_t Offset =
4931     llvm::RoundUpToAlignment(CGF.getContext().getTypeSize(Ty) / 8, TypeAlign);
4932   llvm::Value *NextAddr =
4933     Builder.CreateGEP(AlignedAddr, llvm::ConstantInt::get(IntTy, Offset),
4934                       "ap.next");
4935   Builder.CreateStore(NextAddr, VAListAddrAsBPP);
4936 
4937   return AddrTyped;
4938 }
4939 
4940 bool
4941 MIPSTargetCodeGenInfo::initDwarfEHRegSizeTable(CodeGen::CodeGenFunction &CGF,
4942                                                llvm::Value *Address) const {
4943   // This information comes from gcc's implementation, which seems to
4944   // as canonical as it gets.
4945 
4946   // Everything on MIPS is 4 bytes.  Double-precision FP registers
4947   // are aliased to pairs of single-precision FP registers.
4948   llvm::Value *Four8 = llvm::ConstantInt::get(CGF.Int8Ty, 4);
4949 
4950   // 0-31 are the general purpose registers, $0 - $31.
4951   // 32-63 are the floating-point registers, $f0 - $f31.
4952   // 64 and 65 are the multiply/divide registers, $hi and $lo.
4953   // 66 is the (notional, I think) register for signal-handler return.
4954   AssignToArrayRange(CGF.Builder, Address, Four8, 0, 65);
4955 
4956   // 67-74 are the floating-point status registers, $fcc0 - $fcc7.
4957   // They are one bit wide and ignored here.
4958 
4959   // 80-111 are the coprocessor 0 registers, $c0r0 - $c0r31.
4960   // (coprocessor 1 is the FP unit)
4961   // 112-143 are the coprocessor 2 registers, $c2r0 - $c2r31.
4962   // 144-175 are the coprocessor 3 registers, $c3r0 - $c3r31.
4963   // 176-181 are the DSP accumulator registers.
4964   AssignToArrayRange(CGF.Builder, Address, Four8, 80, 181);
4965   return false;
4966 }
4967 
4968 //===----------------------------------------------------------------------===//
4969 // TCE ABI Implementation (see http://tce.cs.tut.fi). Uses mostly the defaults.
4970 // Currently subclassed only to implement custom OpenCL C function attribute
4971 // handling.
4972 //===----------------------------------------------------------------------===//
4973 
4974 namespace {
4975 
4976 class TCETargetCodeGenInfo : public DefaultTargetCodeGenInfo {
4977 public:
4978   TCETargetCodeGenInfo(CodeGenTypes &CGT)
4979     : DefaultTargetCodeGenInfo(CGT) {}
4980 
4981   virtual void SetTargetAttributes(const Decl *D, llvm::GlobalValue *GV,
4982                                    CodeGen::CodeGenModule &M) const;
4983 };
4984 
4985 void TCETargetCodeGenInfo::SetTargetAttributes(const Decl *D,
4986                                                llvm::GlobalValue *GV,
4987                                                CodeGen::CodeGenModule &M) const {
4988   const FunctionDecl *FD = dyn_cast<FunctionDecl>(D);
4989   if (!FD) return;
4990 
4991   llvm::Function *F = cast<llvm::Function>(GV);
4992 
4993   if (M.getLangOpts().OpenCL) {
4994     if (FD->hasAttr<OpenCLKernelAttr>()) {
4995       // OpenCL C Kernel functions are not subject to inlining
4996       F->addFnAttr(llvm::Attribute::NoInline);
4997 
4998       if (FD->hasAttr<ReqdWorkGroupSizeAttr>()) {
4999 
5000         // Convert the reqd_work_group_size() attributes to metadata.
5001         llvm::LLVMContext &Context = F->getContext();
5002         llvm::NamedMDNode *OpenCLMetadata =
5003             M.getModule().getOrInsertNamedMetadata("opencl.kernel_wg_size_info");
5004 
5005         SmallVector<llvm::Value*, 5> Operands;
5006         Operands.push_back(F);
5007 
5008         Operands.push_back(llvm::Constant::getIntegerValue(M.Int32Ty,
5009                              llvm::APInt(32,
5010                              FD->getAttr<ReqdWorkGroupSizeAttr>()->getXDim())));
5011         Operands.push_back(llvm::Constant::getIntegerValue(M.Int32Ty,
5012                              llvm::APInt(32,
5013                                FD->getAttr<ReqdWorkGroupSizeAttr>()->getYDim())));
5014         Operands.push_back(llvm::Constant::getIntegerValue(M.Int32Ty,
5015                              llvm::APInt(32,
5016                                FD->getAttr<ReqdWorkGroupSizeAttr>()->getZDim())));
5017 
5018         // Add a boolean constant operand for "required" (true) or "hint" (false)
5019         // for implementing the work_group_size_hint attr later. Currently
5020         // always true as the hint is not yet implemented.
5021         Operands.push_back(llvm::ConstantInt::getTrue(Context));
5022         OpenCLMetadata->addOperand(llvm::MDNode::get(Context, Operands));
5023       }
5024     }
5025   }
5026 }
5027 
5028 }
5029 
5030 //===----------------------------------------------------------------------===//
5031 // Hexagon ABI Implementation
5032 //===----------------------------------------------------------------------===//
5033 
5034 namespace {
5035 
5036 class HexagonABIInfo : public ABIInfo {
5037 
5038 
5039 public:
5040   HexagonABIInfo(CodeGenTypes &CGT) : ABIInfo(CGT) {}
5041 
5042 private:
5043 
5044   ABIArgInfo classifyReturnType(QualType RetTy) const;
5045   ABIArgInfo classifyArgumentType(QualType RetTy) const;
5046 
5047   virtual void computeInfo(CGFunctionInfo &FI) const;
5048 
5049   virtual llvm::Value *EmitVAArg(llvm::Value *VAListAddr, QualType Ty,
5050                                  CodeGenFunction &CGF) const;
5051 };
5052 
5053 class HexagonTargetCodeGenInfo : public TargetCodeGenInfo {
5054 public:
5055   HexagonTargetCodeGenInfo(CodeGenTypes &CGT)
5056     :TargetCodeGenInfo(new HexagonABIInfo(CGT)) {}
5057 
5058   int getDwarfEHStackPointer(CodeGen::CodeGenModule &M) const {
5059     return 29;
5060   }
5061 };
5062 
5063 }
5064 
5065 void HexagonABIInfo::computeInfo(CGFunctionInfo &FI) const {
5066   FI.getReturnInfo() = classifyReturnType(FI.getReturnType());
5067   for (CGFunctionInfo::arg_iterator it = FI.arg_begin(), ie = FI.arg_end();
5068        it != ie; ++it)
5069     it->info = classifyArgumentType(it->type);
5070 }
5071 
5072 ABIArgInfo HexagonABIInfo::classifyArgumentType(QualType Ty) const {
5073   if (!isAggregateTypeForABI(Ty)) {
5074     // Treat an enum type as its underlying type.
5075     if (const EnumType *EnumTy = Ty->getAs<EnumType>())
5076       Ty = EnumTy->getDecl()->getIntegerType();
5077 
5078     return (Ty->isPromotableIntegerType() ?
5079             ABIArgInfo::getExtend() : ABIArgInfo::getDirect());
5080   }
5081 
5082   // Ignore empty records.
5083   if (isEmptyRecord(getContext(), Ty, true))
5084     return ABIArgInfo::getIgnore();
5085 
5086   if (CGCXXABI::RecordArgABI RAA = getRecordArgABI(Ty, getCXXABI()))
5087     return ABIArgInfo::getIndirect(0, RAA == CGCXXABI::RAA_DirectInMemory);
5088 
5089   uint64_t Size = getContext().getTypeSize(Ty);
5090   if (Size > 64)
5091     return ABIArgInfo::getIndirect(0, /*ByVal=*/true);
5092     // Pass in the smallest viable integer type.
5093   else if (Size > 32)
5094       return ABIArgInfo::getDirect(llvm::Type::getInt64Ty(getVMContext()));
5095   else if (Size > 16)
5096       return ABIArgInfo::getDirect(llvm::Type::getInt32Ty(getVMContext()));
5097   else if (Size > 8)
5098       return ABIArgInfo::getDirect(llvm::Type::getInt16Ty(getVMContext()));
5099   else
5100       return ABIArgInfo::getDirect(llvm::Type::getInt8Ty(getVMContext()));
5101 }
5102 
5103 ABIArgInfo HexagonABIInfo::classifyReturnType(QualType RetTy) const {
5104   if (RetTy->isVoidType())
5105     return ABIArgInfo::getIgnore();
5106 
5107   // Large vector types should be returned via memory.
5108   if (RetTy->isVectorType() && getContext().getTypeSize(RetTy) > 64)
5109     return ABIArgInfo::getIndirect(0);
5110 
5111   if (!isAggregateTypeForABI(RetTy)) {
5112     // Treat an enum type as its underlying type.
5113     if (const EnumType *EnumTy = RetTy->getAs<EnumType>())
5114       RetTy = EnumTy->getDecl()->getIntegerType();
5115 
5116     return (RetTy->isPromotableIntegerType() ?
5117             ABIArgInfo::getExtend() : ABIArgInfo::getDirect());
5118   }
5119 
5120   // Structures with either a non-trivial destructor or a non-trivial
5121   // copy constructor are always indirect.
5122   if (isRecordReturnIndirect(RetTy, getCXXABI()))
5123     return ABIArgInfo::getIndirect(0, /*ByVal=*/false);
5124 
5125   if (isEmptyRecord(getContext(), RetTy, true))
5126     return ABIArgInfo::getIgnore();
5127 
5128   // Aggregates <= 8 bytes are returned in r0; other aggregates
5129   // are returned indirectly.
5130   uint64_t Size = getContext().getTypeSize(RetTy);
5131   if (Size <= 64) {
5132     // Return in the smallest viable integer type.
5133     if (Size <= 8)
5134       return ABIArgInfo::getDirect(llvm::Type::getInt8Ty(getVMContext()));
5135     if (Size <= 16)
5136       return ABIArgInfo::getDirect(llvm::Type::getInt16Ty(getVMContext()));
5137     if (Size <= 32)
5138       return ABIArgInfo::getDirect(llvm::Type::getInt32Ty(getVMContext()));
5139     return ABIArgInfo::getDirect(llvm::Type::getInt64Ty(getVMContext()));
5140   }
5141 
5142   return ABIArgInfo::getIndirect(0, /*ByVal=*/true);
5143 }
5144 
5145 llvm::Value *HexagonABIInfo::EmitVAArg(llvm::Value *VAListAddr, QualType Ty,
5146                                        CodeGenFunction &CGF) const {
5147   // FIXME: Need to handle alignment
5148   llvm::Type *BPP = CGF.Int8PtrPtrTy;
5149 
5150   CGBuilderTy &Builder = CGF.Builder;
5151   llvm::Value *VAListAddrAsBPP = Builder.CreateBitCast(VAListAddr, BPP,
5152                                                        "ap");
5153   llvm::Value *Addr = Builder.CreateLoad(VAListAddrAsBPP, "ap.cur");
5154   llvm::Type *PTy =
5155     llvm::PointerType::getUnqual(CGF.ConvertType(Ty));
5156   llvm::Value *AddrTyped = Builder.CreateBitCast(Addr, PTy);
5157 
5158   uint64_t Offset =
5159     llvm::RoundUpToAlignment(CGF.getContext().getTypeSize(Ty) / 8, 4);
5160   llvm::Value *NextAddr =
5161     Builder.CreateGEP(Addr, llvm::ConstantInt::get(CGF.Int32Ty, Offset),
5162                       "ap.next");
5163   Builder.CreateStore(NextAddr, VAListAddrAsBPP);
5164 
5165   return AddrTyped;
5166 }
5167 
5168 
5169 //===----------------------------------------------------------------------===//
5170 // SPARC v9 ABI Implementation.
5171 // Based on the SPARC Compliance Definition version 2.4.1.
5172 //
5173 // Function arguments a mapped to a nominal "parameter array" and promoted to
5174 // registers depending on their type. Each argument occupies 8 or 16 bytes in
5175 // the array, structs larger than 16 bytes are passed indirectly.
5176 //
5177 // One case requires special care:
5178 //
5179 //   struct mixed {
5180 //     int i;
5181 //     float f;
5182 //   };
5183 //
5184 // When a struct mixed is passed by value, it only occupies 8 bytes in the
5185 // parameter array, but the int is passed in an integer register, and the float
5186 // is passed in a floating point register. This is represented as two arguments
5187 // with the LLVM IR inreg attribute:
5188 //
5189 //   declare void f(i32 inreg %i, float inreg %f)
5190 //
5191 // The code generator will only allocate 4 bytes from the parameter array for
5192 // the inreg arguments. All other arguments are allocated a multiple of 8
5193 // bytes.
5194 //
5195 namespace {
5196 class SparcV9ABIInfo : public ABIInfo {
5197 public:
5198   SparcV9ABIInfo(CodeGenTypes &CGT) : ABIInfo(CGT) {}
5199 
5200 private:
5201   ABIArgInfo classifyType(QualType RetTy, unsigned SizeLimit) const;
5202   virtual void computeInfo(CGFunctionInfo &FI) const;
5203   virtual llvm::Value *EmitVAArg(llvm::Value *VAListAddr, QualType Ty,
5204                                  CodeGenFunction &CGF) const;
5205 
5206   // Coercion type builder for structs passed in registers. The coercion type
5207   // serves two purposes:
5208   //
5209   // 1. Pad structs to a multiple of 64 bits, so they are passed 'left-aligned'
5210   //    in registers.
5211   // 2. Expose aligned floating point elements as first-level elements, so the
5212   //    code generator knows to pass them in floating point registers.
5213   //
5214   // We also compute the InReg flag which indicates that the struct contains
5215   // aligned 32-bit floats.
5216   //
5217   struct CoerceBuilder {
5218     llvm::LLVMContext &Context;
5219     const llvm::DataLayout &DL;
5220     SmallVector<llvm::Type*, 8> Elems;
5221     uint64_t Size;
5222     bool InReg;
5223 
5224     CoerceBuilder(llvm::LLVMContext &c, const llvm::DataLayout &dl)
5225       : Context(c), DL(dl), Size(0), InReg(false) {}
5226 
5227     // Pad Elems with integers until Size is ToSize.
5228     void pad(uint64_t ToSize) {
5229       assert(ToSize >= Size && "Cannot remove elements");
5230       if (ToSize == Size)
5231         return;
5232 
5233       // Finish the current 64-bit word.
5234       uint64_t Aligned = llvm::RoundUpToAlignment(Size, 64);
5235       if (Aligned > Size && Aligned <= ToSize) {
5236         Elems.push_back(llvm::IntegerType::get(Context, Aligned - Size));
5237         Size = Aligned;
5238       }
5239 
5240       // Add whole 64-bit words.
5241       while (Size + 64 <= ToSize) {
5242         Elems.push_back(llvm::Type::getInt64Ty(Context));
5243         Size += 64;
5244       }
5245 
5246       // Final in-word padding.
5247       if (Size < ToSize) {
5248         Elems.push_back(llvm::IntegerType::get(Context, ToSize - Size));
5249         Size = ToSize;
5250       }
5251     }
5252 
5253     // Add a floating point element at Offset.
5254     void addFloat(uint64_t Offset, llvm::Type *Ty, unsigned Bits) {
5255       // Unaligned floats are treated as integers.
5256       if (Offset % Bits)
5257         return;
5258       // The InReg flag is only required if there are any floats < 64 bits.
5259       if (Bits < 64)
5260         InReg = true;
5261       pad(Offset);
5262       Elems.push_back(Ty);
5263       Size = Offset + Bits;
5264     }
5265 
5266     // Add a struct type to the coercion type, starting at Offset (in bits).
5267     void addStruct(uint64_t Offset, llvm::StructType *StrTy) {
5268       const llvm::StructLayout *Layout = DL.getStructLayout(StrTy);
5269       for (unsigned i = 0, e = StrTy->getNumElements(); i != e; ++i) {
5270         llvm::Type *ElemTy = StrTy->getElementType(i);
5271         uint64_t ElemOffset = Offset + Layout->getElementOffsetInBits(i);
5272         switch (ElemTy->getTypeID()) {
5273         case llvm::Type::StructTyID:
5274           addStruct(ElemOffset, cast<llvm::StructType>(ElemTy));
5275           break;
5276         case llvm::Type::FloatTyID:
5277           addFloat(ElemOffset, ElemTy, 32);
5278           break;
5279         case llvm::Type::DoubleTyID:
5280           addFloat(ElemOffset, ElemTy, 64);
5281           break;
5282         case llvm::Type::FP128TyID:
5283           addFloat(ElemOffset, ElemTy, 128);
5284           break;
5285         case llvm::Type::PointerTyID:
5286           if (ElemOffset % 64 == 0) {
5287             pad(ElemOffset);
5288             Elems.push_back(ElemTy);
5289             Size += 64;
5290           }
5291           break;
5292         default:
5293           break;
5294         }
5295       }
5296     }
5297 
5298     // Check if Ty is a usable substitute for the coercion type.
5299     bool isUsableType(llvm::StructType *Ty) const {
5300       if (Ty->getNumElements() != Elems.size())
5301         return false;
5302       for (unsigned i = 0, e = Elems.size(); i != e; ++i)
5303         if (Elems[i] != Ty->getElementType(i))
5304           return false;
5305       return true;
5306     }
5307 
5308     // Get the coercion type as a literal struct type.
5309     llvm::Type *getType() const {
5310       if (Elems.size() == 1)
5311         return Elems.front();
5312       else
5313         return llvm::StructType::get(Context, Elems);
5314     }
5315   };
5316 };
5317 } // end anonymous namespace
5318 
5319 ABIArgInfo
5320 SparcV9ABIInfo::classifyType(QualType Ty, unsigned SizeLimit) const {
5321   if (Ty->isVoidType())
5322     return ABIArgInfo::getIgnore();
5323 
5324   uint64_t Size = getContext().getTypeSize(Ty);
5325 
5326   // Anything too big to fit in registers is passed with an explicit indirect
5327   // pointer / sret pointer.
5328   if (Size > SizeLimit)
5329     return ABIArgInfo::getIndirect(0, /*ByVal=*/false);
5330 
5331   // Treat an enum type as its underlying type.
5332   if (const EnumType *EnumTy = Ty->getAs<EnumType>())
5333     Ty = EnumTy->getDecl()->getIntegerType();
5334 
5335   // Integer types smaller than a register are extended.
5336   if (Size < 64 && Ty->isIntegerType())
5337     return ABIArgInfo::getExtend();
5338 
5339   // Other non-aggregates go in registers.
5340   if (!isAggregateTypeForABI(Ty))
5341     return ABIArgInfo::getDirect();
5342 
5343   // This is a small aggregate type that should be passed in registers.
5344   // Build a coercion type from the LLVM struct type.
5345   llvm::StructType *StrTy = dyn_cast<llvm::StructType>(CGT.ConvertType(Ty));
5346   if (!StrTy)
5347     return ABIArgInfo::getDirect();
5348 
5349   CoerceBuilder CB(getVMContext(), getDataLayout());
5350   CB.addStruct(0, StrTy);
5351   CB.pad(llvm::RoundUpToAlignment(CB.DL.getTypeSizeInBits(StrTy), 64));
5352 
5353   // Try to use the original type for coercion.
5354   llvm::Type *CoerceTy = CB.isUsableType(StrTy) ? StrTy : CB.getType();
5355 
5356   if (CB.InReg)
5357     return ABIArgInfo::getDirectInReg(CoerceTy);
5358   else
5359     return ABIArgInfo::getDirect(CoerceTy);
5360 }
5361 
5362 llvm::Value *SparcV9ABIInfo::EmitVAArg(llvm::Value *VAListAddr, QualType Ty,
5363                                        CodeGenFunction &CGF) const {
5364   ABIArgInfo AI = classifyType(Ty, 16 * 8);
5365   llvm::Type *ArgTy = CGT.ConvertType(Ty);
5366   if (AI.canHaveCoerceToType() && !AI.getCoerceToType())
5367     AI.setCoerceToType(ArgTy);
5368 
5369   llvm::Type *BPP = CGF.Int8PtrPtrTy;
5370   CGBuilderTy &Builder = CGF.Builder;
5371   llvm::Value *VAListAddrAsBPP = Builder.CreateBitCast(VAListAddr, BPP, "ap");
5372   llvm::Value *Addr = Builder.CreateLoad(VAListAddrAsBPP, "ap.cur");
5373   llvm::Type *ArgPtrTy = llvm::PointerType::getUnqual(ArgTy);
5374   llvm::Value *ArgAddr;
5375   unsigned Stride;
5376 
5377   switch (AI.getKind()) {
5378   case ABIArgInfo::Expand:
5379     llvm_unreachable("Unsupported ABI kind for va_arg");
5380 
5381   case ABIArgInfo::Extend:
5382     Stride = 8;
5383     ArgAddr = Builder
5384       .CreateConstGEP1_32(Addr, 8 - getDataLayout().getTypeAllocSize(ArgTy),
5385                           "extend");
5386     break;
5387 
5388   case ABIArgInfo::Direct:
5389     Stride = getDataLayout().getTypeAllocSize(AI.getCoerceToType());
5390     ArgAddr = Addr;
5391     break;
5392 
5393   case ABIArgInfo::Indirect:
5394     Stride = 8;
5395     ArgAddr = Builder.CreateBitCast(Addr,
5396                                     llvm::PointerType::getUnqual(ArgPtrTy),
5397                                     "indirect");
5398     ArgAddr = Builder.CreateLoad(ArgAddr, "indirect.arg");
5399     break;
5400 
5401   case ABIArgInfo::Ignore:
5402     return llvm::UndefValue::get(ArgPtrTy);
5403   }
5404 
5405   // Update VAList.
5406   Addr = Builder.CreateConstGEP1_32(Addr, Stride, "ap.next");
5407   Builder.CreateStore(Addr, VAListAddrAsBPP);
5408 
5409   return Builder.CreatePointerCast(ArgAddr, ArgPtrTy, "arg.addr");
5410 }
5411 
5412 void SparcV9ABIInfo::computeInfo(CGFunctionInfo &FI) const {
5413   FI.getReturnInfo() = classifyType(FI.getReturnType(), 32 * 8);
5414   for (CGFunctionInfo::arg_iterator it = FI.arg_begin(), ie = FI.arg_end();
5415        it != ie; ++it)
5416     it->info = classifyType(it->type, 16 * 8);
5417 }
5418 
5419 namespace {
5420 class SparcV9TargetCodeGenInfo : public TargetCodeGenInfo {
5421 public:
5422   SparcV9TargetCodeGenInfo(CodeGenTypes &CGT)
5423     : TargetCodeGenInfo(new SparcV9ABIInfo(CGT)) {}
5424 };
5425 } // end anonymous namespace
5426 
5427 
5428 //===----------------------------------------------------------------------===//
5429 // Xcore ABI Implementation
5430 //===----------------------------------------------------------------------===//
5431 namespace {
5432 class XCoreABIInfo : public DefaultABIInfo {
5433 public:
5434   XCoreABIInfo(CodeGen::CodeGenTypes &CGT) : DefaultABIInfo(CGT) {}
5435   virtual llvm::Value *EmitVAArg(llvm::Value *VAListAddr, QualType Ty,
5436                                  CodeGenFunction &CGF) const;
5437 };
5438 
5439 class XcoreTargetCodeGenInfo : public TargetCodeGenInfo {
5440 public:
5441   XcoreTargetCodeGenInfo(CodeGenTypes &CGT)
5442     :TargetCodeGenInfo(new XCoreABIInfo(CGT)) {}
5443 };
5444 } // End anonymous namespace.
5445 
5446 llvm::Value *XCoreABIInfo::EmitVAArg(llvm::Value *VAListAddr, QualType Ty,
5447                                      CodeGenFunction &CGF) const {
5448   CGBuilderTy &Builder = CGF.Builder;
5449 
5450   // Get the VAList.
5451   llvm::Value *VAListAddrAsBPP = Builder.CreateBitCast(VAListAddr,
5452                                                        CGF.Int8PtrPtrTy);
5453   llvm::Value *AP = Builder.CreateLoad(VAListAddrAsBPP);
5454 
5455   // Handle the argument.
5456   ABIArgInfo AI = classifyArgumentType(Ty);
5457   llvm::Type *ArgTy = CGT.ConvertType(Ty);
5458   if (AI.canHaveCoerceToType() && !AI.getCoerceToType())
5459     AI.setCoerceToType(ArgTy);
5460   llvm::Type *ArgPtrTy = llvm::PointerType::getUnqual(ArgTy);
5461   llvm::Value *Val;
5462   uint64_t ArgSize = 0;
5463   switch (AI.getKind()) {
5464   case ABIArgInfo::Expand:
5465     llvm_unreachable("Unsupported ABI kind for va_arg");
5466   case ABIArgInfo::Ignore:
5467     Val = llvm::UndefValue::get(ArgPtrTy);
5468     ArgSize = 0;
5469     break;
5470   case ABIArgInfo::Extend:
5471   case ABIArgInfo::Direct:
5472     Val = Builder.CreatePointerCast(AP, ArgPtrTy);
5473     ArgSize = getDataLayout().getTypeAllocSize(AI.getCoerceToType());
5474     if (ArgSize < 4)
5475       ArgSize = 4;
5476     break;
5477   case ABIArgInfo::Indirect:
5478     llvm::Value *ArgAddr;
5479     ArgAddr = Builder.CreateBitCast(AP, llvm::PointerType::getUnqual(ArgPtrTy));
5480     ArgAddr = Builder.CreateLoad(ArgAddr);
5481     Val = Builder.CreatePointerCast(ArgAddr, ArgPtrTy);
5482     ArgSize = 4;
5483     break;
5484   }
5485 
5486   // Increment the VAList.
5487   if (ArgSize) {
5488     llvm::Value *APN = Builder.CreateConstGEP1_32(AP, ArgSize);
5489     Builder.CreateStore(APN, VAListAddrAsBPP);
5490   }
5491   return Val;
5492 }
5493 
5494 //===----------------------------------------------------------------------===//
5495 // Driver code
5496 //===----------------------------------------------------------------------===//
5497 
5498 const TargetCodeGenInfo &CodeGenModule::getTargetCodeGenInfo() {
5499   if (TheTargetCodeGenInfo)
5500     return *TheTargetCodeGenInfo;
5501 
5502   const llvm::Triple &Triple = getTarget().getTriple();
5503   switch (Triple.getArch()) {
5504   default:
5505     return *(TheTargetCodeGenInfo = new DefaultTargetCodeGenInfo(Types));
5506 
5507   case llvm::Triple::le32:
5508     return *(TheTargetCodeGenInfo = new PNaClTargetCodeGenInfo(Types));
5509   case llvm::Triple::mips:
5510   case llvm::Triple::mipsel:
5511     return *(TheTargetCodeGenInfo = new MIPSTargetCodeGenInfo(Types, true,
5512                                                               getTarget()));
5513   case llvm::Triple::mips64:
5514   case llvm::Triple::mips64el:
5515     return *(TheTargetCodeGenInfo = new MIPSTargetCodeGenInfo(Types, false,
5516                                                               getTarget()));
5517   case llvm::Triple::aarch64:
5518     return *(TheTargetCodeGenInfo = new AArch64TargetCodeGenInfo(Types));
5519 
5520   case llvm::Triple::arm:
5521   case llvm::Triple::thumb:
5522     {
5523       ARMABIInfo::ABIKind Kind = ARMABIInfo::AAPCS;
5524       if (strcmp(getTarget().getABI(), "apcs-gnu") == 0)
5525         Kind = ARMABIInfo::APCS;
5526       else if (CodeGenOpts.FloatABI == "hard" ||
5527                (CodeGenOpts.FloatABI != "soft" &&
5528                 Triple.getEnvironment() == llvm::Triple::GNUEABIHF))
5529         Kind = ARMABIInfo::AAPCS_VFP;
5530 
5531       switch (Triple.getOS()) {
5532         case llvm::Triple::NaCl:
5533           return *(TheTargetCodeGenInfo =
5534                    new NaClARMTargetCodeGenInfo(Types, Kind));
5535         default:
5536           return *(TheTargetCodeGenInfo =
5537                    new ARMTargetCodeGenInfo(Types, Kind));
5538       }
5539     }
5540 
5541   case llvm::Triple::ppc:
5542     return *(TheTargetCodeGenInfo = new PPC32TargetCodeGenInfo(Types));
5543   case llvm::Triple::ppc64:
5544     if (Triple.isOSBinFormatELF())
5545       return *(TheTargetCodeGenInfo = new PPC64_SVR4_TargetCodeGenInfo(Types));
5546     else
5547       return *(TheTargetCodeGenInfo = new PPC64TargetCodeGenInfo(Types));
5548   case llvm::Triple::ppc64le:
5549     assert(Triple.isOSBinFormatELF() && "PPC64 LE non-ELF not supported!");
5550     return *(TheTargetCodeGenInfo = new PPC64_SVR4_TargetCodeGenInfo(Types));
5551 
5552   case llvm::Triple::nvptx:
5553   case llvm::Triple::nvptx64:
5554     return *(TheTargetCodeGenInfo = new NVPTXTargetCodeGenInfo(Types));
5555 
5556   case llvm::Triple::msp430:
5557     return *(TheTargetCodeGenInfo = new MSP430TargetCodeGenInfo(Types));
5558 
5559   case llvm::Triple::systemz:
5560     return *(TheTargetCodeGenInfo = new SystemZTargetCodeGenInfo(Types));
5561 
5562   case llvm::Triple::tce:
5563     return *(TheTargetCodeGenInfo = new TCETargetCodeGenInfo(Types));
5564 
5565   case llvm::Triple::x86: {
5566     bool IsDarwinVectorABI = Triple.isOSDarwin();
5567     bool IsSmallStructInRegABI =
5568         X86_32TargetCodeGenInfo::isStructReturnInRegABI(Triple, CodeGenOpts);
5569     bool IsWin32FloatStructABI = (Triple.getOS() == llvm::Triple::Win32);
5570 
5571     if (Triple.getOS() == llvm::Triple::Win32) {
5572       return *(TheTargetCodeGenInfo =
5573                new WinX86_32TargetCodeGenInfo(Types,
5574                                               IsDarwinVectorABI, IsSmallStructInRegABI,
5575                                               IsWin32FloatStructABI,
5576                                               CodeGenOpts.NumRegisterParameters));
5577     } else {
5578       return *(TheTargetCodeGenInfo =
5579                new X86_32TargetCodeGenInfo(Types,
5580                                            IsDarwinVectorABI, IsSmallStructInRegABI,
5581                                            IsWin32FloatStructABI,
5582                                            CodeGenOpts.NumRegisterParameters));
5583     }
5584   }
5585 
5586   case llvm::Triple::x86_64: {
5587     bool HasAVX = strcmp(getTarget().getABI(), "avx") == 0;
5588 
5589     switch (Triple.getOS()) {
5590     case llvm::Triple::Win32:
5591     case llvm::Triple::MinGW32:
5592     case llvm::Triple::Cygwin:
5593       return *(TheTargetCodeGenInfo = new WinX86_64TargetCodeGenInfo(Types));
5594     case llvm::Triple::NaCl:
5595       return *(TheTargetCodeGenInfo = new NaClX86_64TargetCodeGenInfo(Types,
5596                                                                       HasAVX));
5597     default:
5598       return *(TheTargetCodeGenInfo = new X86_64TargetCodeGenInfo(Types,
5599                                                                   HasAVX));
5600     }
5601   }
5602   case llvm::Triple::hexagon:
5603     return *(TheTargetCodeGenInfo = new HexagonTargetCodeGenInfo(Types));
5604   case llvm::Triple::sparcv9:
5605     return *(TheTargetCodeGenInfo = new SparcV9TargetCodeGenInfo(Types));
5606   case llvm::Triple::xcore:
5607     return *(TheTargetCodeGenInfo = new XcoreTargetCodeGenInfo(Types));
5608 
5609   }
5610 }
5611