1 //===---- TargetInfo.cpp - Encapsulate target details -----------*- C++ -*-===//
2 //
3 //                     The LLVM Compiler Infrastructure
4 //
5 // This file is distributed under the University of Illinois Open Source
6 // License. See LICENSE.TXT for details.
7 //
8 //===----------------------------------------------------------------------===//
9 //
10 // These classes wrap the information about a call or function
11 // definition used to handle ABI compliancy.
12 //
13 //===----------------------------------------------------------------------===//
14 
15 #include "TargetInfo.h"
16 #include "ABIInfo.h"
17 #include "CGCXXABI.h"
18 #include "CodeGenFunction.h"
19 #include "clang/AST/RecordLayout.h"
20 #include "clang/CodeGen/CGFunctionInfo.h"
21 #include "clang/Frontend/CodeGenOptions.h"
22 #include "llvm/ADT/Triple.h"
23 #include "llvm/IR/DataLayout.h"
24 #include "llvm/IR/Type.h"
25 #include "llvm/Support/raw_ostream.h"
26 using namespace clang;
27 using namespace CodeGen;
28 
29 static void AssignToArrayRange(CodeGen::CGBuilderTy &Builder,
30                                llvm::Value *Array,
31                                llvm::Value *Value,
32                                unsigned FirstIndex,
33                                unsigned LastIndex) {
34   // Alternatively, we could emit this as a loop in the source.
35   for (unsigned I = FirstIndex; I <= LastIndex; ++I) {
36     llvm::Value *Cell = Builder.CreateConstInBoundsGEP1_32(Array, I);
37     Builder.CreateStore(Value, Cell);
38   }
39 }
40 
41 static bool isAggregateTypeForABI(QualType T) {
42   return !CodeGenFunction::hasScalarEvaluationKind(T) ||
43          T->isMemberFunctionPointerType();
44 }
45 
46 ABIInfo::~ABIInfo() {}
47 
48 static bool isRecordReturnIndirect(const RecordType *RT,
49                                    CGCXXABI &CXXABI) {
50   const CXXRecordDecl *RD = dyn_cast<CXXRecordDecl>(RT->getDecl());
51   if (!RD)
52     return false;
53   return CXXABI.isReturnTypeIndirect(RD);
54 }
55 
56 
57 static bool isRecordReturnIndirect(QualType T, CGCXXABI &CXXABI) {
58   const RecordType *RT = T->getAs<RecordType>();
59   if (!RT)
60     return false;
61   return isRecordReturnIndirect(RT, CXXABI);
62 }
63 
64 static CGCXXABI::RecordArgABI getRecordArgABI(const RecordType *RT,
65                                               CGCXXABI &CXXABI) {
66   const CXXRecordDecl *RD = dyn_cast<CXXRecordDecl>(RT->getDecl());
67   if (!RD)
68     return CGCXXABI::RAA_Default;
69   return CXXABI.getRecordArgABI(RD);
70 }
71 
72 static CGCXXABI::RecordArgABI getRecordArgABI(QualType T,
73                                               CGCXXABI &CXXABI) {
74   const RecordType *RT = T->getAs<RecordType>();
75   if (!RT)
76     return CGCXXABI::RAA_Default;
77   return getRecordArgABI(RT, CXXABI);
78 }
79 
80 CGCXXABI &ABIInfo::getCXXABI() const {
81   return CGT.getCXXABI();
82 }
83 
84 ASTContext &ABIInfo::getContext() const {
85   return CGT.getContext();
86 }
87 
88 llvm::LLVMContext &ABIInfo::getVMContext() const {
89   return CGT.getLLVMContext();
90 }
91 
92 const llvm::DataLayout &ABIInfo::getDataLayout() const {
93   return CGT.getDataLayout();
94 }
95 
96 const TargetInfo &ABIInfo::getTarget() const {
97   return CGT.getTarget();
98 }
99 
100 void ABIArgInfo::dump() const {
101   raw_ostream &OS = llvm::errs();
102   OS << "(ABIArgInfo Kind=";
103   switch (TheKind) {
104   case Direct:
105     OS << "Direct Type=";
106     if (llvm::Type *Ty = getCoerceToType())
107       Ty->print(OS);
108     else
109       OS << "null";
110     break;
111   case Extend:
112     OS << "Extend";
113     break;
114   case Ignore:
115     OS << "Ignore";
116     break;
117   case Indirect:
118     OS << "Indirect Align=" << getIndirectAlign()
119        << " ByVal=" << getIndirectByVal()
120        << " Realign=" << getIndirectRealign();
121     break;
122   case Expand:
123     OS << "Expand";
124     break;
125   }
126   OS << ")\n";
127 }
128 
129 TargetCodeGenInfo::~TargetCodeGenInfo() { delete Info; }
130 
131 // If someone can figure out a general rule for this, that would be great.
132 // It's probably just doomed to be platform-dependent, though.
133 unsigned TargetCodeGenInfo::getSizeOfUnwindException() const {
134   // Verified for:
135   //   x86-64     FreeBSD, Linux, Darwin
136   //   x86-32     FreeBSD, Linux, Darwin
137   //   PowerPC    Linux, Darwin
138   //   ARM        Darwin (*not* EABI)
139   //   AArch64    Linux
140   return 32;
141 }
142 
143 bool TargetCodeGenInfo::isNoProtoCallVariadic(const CallArgList &args,
144                                      const FunctionNoProtoType *fnType) const {
145   // The following conventions are known to require this to be false:
146   //   x86_stdcall
147   //   MIPS
148   // For everything else, we just prefer false unless we opt out.
149   return false;
150 }
151 
152 void
153 TargetCodeGenInfo::getDependentLibraryOption(llvm::StringRef Lib,
154                                              llvm::SmallString<24> &Opt) const {
155   // This assumes the user is passing a library name like "rt" instead of a
156   // filename like "librt.a/so", and that they don't care whether it's static or
157   // dynamic.
158   Opt = "-l";
159   Opt += Lib;
160 }
161 
162 static bool isEmptyRecord(ASTContext &Context, QualType T, bool AllowArrays);
163 
164 /// isEmptyField - Return true iff a the field is "empty", that is it
165 /// is an unnamed bit-field or an (array of) empty record(s).
166 static bool isEmptyField(ASTContext &Context, const FieldDecl *FD,
167                          bool AllowArrays) {
168   if (FD->isUnnamedBitfield())
169     return true;
170 
171   QualType FT = FD->getType();
172 
173   // Constant arrays of empty records count as empty, strip them off.
174   // Constant arrays of zero length always count as empty.
175   if (AllowArrays)
176     while (const ConstantArrayType *AT = Context.getAsConstantArrayType(FT)) {
177       if (AT->getSize() == 0)
178         return true;
179       FT = AT->getElementType();
180     }
181 
182   const RecordType *RT = FT->getAs<RecordType>();
183   if (!RT)
184     return false;
185 
186   // C++ record fields are never empty, at least in the Itanium ABI.
187   //
188   // FIXME: We should use a predicate for whether this behavior is true in the
189   // current ABI.
190   if (isa<CXXRecordDecl>(RT->getDecl()))
191     return false;
192 
193   return isEmptyRecord(Context, FT, AllowArrays);
194 }
195 
196 /// isEmptyRecord - Return true iff a structure contains only empty
197 /// fields. Note that a structure with a flexible array member is not
198 /// considered empty.
199 static bool isEmptyRecord(ASTContext &Context, QualType T, bool AllowArrays) {
200   const RecordType *RT = T->getAs<RecordType>();
201   if (!RT)
202     return 0;
203   const RecordDecl *RD = RT->getDecl();
204   if (RD->hasFlexibleArrayMember())
205     return false;
206 
207   // If this is a C++ record, check the bases first.
208   if (const CXXRecordDecl *CXXRD = dyn_cast<CXXRecordDecl>(RD))
209     for (CXXRecordDecl::base_class_const_iterator i = CXXRD->bases_begin(),
210            e = CXXRD->bases_end(); i != e; ++i)
211       if (!isEmptyRecord(Context, i->getType(), true))
212         return false;
213 
214   for (RecordDecl::field_iterator i = RD->field_begin(), e = RD->field_end();
215          i != e; ++i)
216     if (!isEmptyField(Context, *i, AllowArrays))
217       return false;
218   return true;
219 }
220 
221 /// isSingleElementStruct - Determine if a structure is a "single
222 /// element struct", i.e. it has exactly one non-empty field or
223 /// exactly one field which is itself a single element
224 /// struct. Structures with flexible array members are never
225 /// considered single element structs.
226 ///
227 /// \return The field declaration for the single non-empty field, if
228 /// it exists.
229 static const Type *isSingleElementStruct(QualType T, ASTContext &Context) {
230   const RecordType *RT = T->getAsStructureType();
231   if (!RT)
232     return 0;
233 
234   const RecordDecl *RD = RT->getDecl();
235   if (RD->hasFlexibleArrayMember())
236     return 0;
237 
238   const Type *Found = 0;
239 
240   // If this is a C++ record, check the bases first.
241   if (const CXXRecordDecl *CXXRD = dyn_cast<CXXRecordDecl>(RD)) {
242     for (CXXRecordDecl::base_class_const_iterator i = CXXRD->bases_begin(),
243            e = CXXRD->bases_end(); i != e; ++i) {
244       // Ignore empty records.
245       if (isEmptyRecord(Context, i->getType(), true))
246         continue;
247 
248       // If we already found an element then this isn't a single-element struct.
249       if (Found)
250         return 0;
251 
252       // If this is non-empty and not a single element struct, the composite
253       // cannot be a single element struct.
254       Found = isSingleElementStruct(i->getType(), Context);
255       if (!Found)
256         return 0;
257     }
258   }
259 
260   // Check for single element.
261   for (RecordDecl::field_iterator i = RD->field_begin(), e = RD->field_end();
262          i != e; ++i) {
263     const FieldDecl *FD = *i;
264     QualType FT = FD->getType();
265 
266     // Ignore empty fields.
267     if (isEmptyField(Context, FD, true))
268       continue;
269 
270     // If we already found an element then this isn't a single-element
271     // struct.
272     if (Found)
273       return 0;
274 
275     // Treat single element arrays as the element.
276     while (const ConstantArrayType *AT = Context.getAsConstantArrayType(FT)) {
277       if (AT->getSize().getZExtValue() != 1)
278         break;
279       FT = AT->getElementType();
280     }
281 
282     if (!isAggregateTypeForABI(FT)) {
283       Found = FT.getTypePtr();
284     } else {
285       Found = isSingleElementStruct(FT, Context);
286       if (!Found)
287         return 0;
288     }
289   }
290 
291   // We don't consider a struct a single-element struct if it has
292   // padding beyond the element type.
293   if (Found && Context.getTypeSize(Found) != Context.getTypeSize(T))
294     return 0;
295 
296   return Found;
297 }
298 
299 static bool is32Or64BitBasicType(QualType Ty, ASTContext &Context) {
300   // Treat complex types as the element type.
301   if (const ComplexType *CTy = Ty->getAs<ComplexType>())
302     Ty = CTy->getElementType();
303 
304   // Check for a type which we know has a simple scalar argument-passing
305   // convention without any padding.  (We're specifically looking for 32
306   // and 64-bit integer and integer-equivalents, float, and double.)
307   if (!Ty->getAs<BuiltinType>() && !Ty->hasPointerRepresentation() &&
308       !Ty->isEnumeralType() && !Ty->isBlockPointerType())
309     return false;
310 
311   uint64_t Size = Context.getTypeSize(Ty);
312   return Size == 32 || Size == 64;
313 }
314 
315 /// canExpandIndirectArgument - Test whether an argument type which is to be
316 /// passed indirectly (on the stack) would have the equivalent layout if it was
317 /// expanded into separate arguments. If so, we prefer to do the latter to avoid
318 /// inhibiting optimizations.
319 ///
320 // FIXME: This predicate is missing many cases, currently it just follows
321 // llvm-gcc (checks that all fields are 32-bit or 64-bit primitive types). We
322 // should probably make this smarter, or better yet make the LLVM backend
323 // capable of handling it.
324 static bool canExpandIndirectArgument(QualType Ty, ASTContext &Context) {
325   // We can only expand structure types.
326   const RecordType *RT = Ty->getAs<RecordType>();
327   if (!RT)
328     return false;
329 
330   // We can only expand (C) structures.
331   //
332   // FIXME: This needs to be generalized to handle classes as well.
333   const RecordDecl *RD = RT->getDecl();
334   if (!RD->isStruct() || isa<CXXRecordDecl>(RD))
335     return false;
336 
337   uint64_t Size = 0;
338 
339   for (RecordDecl::field_iterator i = RD->field_begin(), e = RD->field_end();
340          i != e; ++i) {
341     const FieldDecl *FD = *i;
342 
343     if (!is32Or64BitBasicType(FD->getType(), Context))
344       return false;
345 
346     // FIXME: Reject bit-fields wholesale; there are two problems, we don't know
347     // how to expand them yet, and the predicate for telling if a bitfield still
348     // counts as "basic" is more complicated than what we were doing previously.
349     if (FD->isBitField())
350       return false;
351 
352     Size += Context.getTypeSize(FD->getType());
353   }
354 
355   // Make sure there are not any holes in the struct.
356   if (Size != Context.getTypeSize(Ty))
357     return false;
358 
359   return true;
360 }
361 
362 namespace {
363 /// DefaultABIInfo - The default implementation for ABI specific
364 /// details. This implementation provides information which results in
365 /// self-consistent and sensible LLVM IR generation, but does not
366 /// conform to any particular ABI.
367 class DefaultABIInfo : public ABIInfo {
368 public:
369   DefaultABIInfo(CodeGen::CodeGenTypes &CGT) : ABIInfo(CGT) {}
370 
371   ABIArgInfo classifyReturnType(QualType RetTy) const;
372   ABIArgInfo classifyArgumentType(QualType RetTy) const;
373 
374   virtual void computeInfo(CGFunctionInfo &FI) const {
375     FI.getReturnInfo() = classifyReturnType(FI.getReturnType());
376     for (CGFunctionInfo::arg_iterator it = FI.arg_begin(), ie = FI.arg_end();
377          it != ie; ++it)
378       it->info = classifyArgumentType(it->type);
379   }
380 
381   virtual llvm::Value *EmitVAArg(llvm::Value *VAListAddr, QualType Ty,
382                                  CodeGenFunction &CGF) const;
383 };
384 
385 class DefaultTargetCodeGenInfo : public TargetCodeGenInfo {
386 public:
387   DefaultTargetCodeGenInfo(CodeGen::CodeGenTypes &CGT)
388     : TargetCodeGenInfo(new DefaultABIInfo(CGT)) {}
389 };
390 
391 llvm::Value *DefaultABIInfo::EmitVAArg(llvm::Value *VAListAddr, QualType Ty,
392                                        CodeGenFunction &CGF) const {
393   return 0;
394 }
395 
396 ABIArgInfo DefaultABIInfo::classifyArgumentType(QualType Ty) const {
397   if (isAggregateTypeForABI(Ty)) {
398     // Records with non-trivial destructors/constructors should not be passed
399     // by value.
400     if (isRecordReturnIndirect(Ty, getCXXABI()))
401       return ABIArgInfo::getIndirect(0, /*ByVal=*/false);
402 
403     return ABIArgInfo::getIndirect(0);
404   }
405 
406   // Treat an enum type as its underlying type.
407   if (const EnumType *EnumTy = Ty->getAs<EnumType>())
408     Ty = EnumTy->getDecl()->getIntegerType();
409 
410   return (Ty->isPromotableIntegerType() ?
411           ABIArgInfo::getExtend() : ABIArgInfo::getDirect());
412 }
413 
414 ABIArgInfo DefaultABIInfo::classifyReturnType(QualType RetTy) const {
415   if (RetTy->isVoidType())
416     return ABIArgInfo::getIgnore();
417 
418   if (isAggregateTypeForABI(RetTy))
419     return ABIArgInfo::getIndirect(0);
420 
421   // Treat an enum type as its underlying type.
422   if (const EnumType *EnumTy = RetTy->getAs<EnumType>())
423     RetTy = EnumTy->getDecl()->getIntegerType();
424 
425   return (RetTy->isPromotableIntegerType() ?
426           ABIArgInfo::getExtend() : ABIArgInfo::getDirect());
427 }
428 
429 //===----------------------------------------------------------------------===//
430 // le32/PNaCl bitcode ABI Implementation
431 //
432 // This is a simplified version of the x86_32 ABI.  Arguments and return values
433 // are always passed on the stack.
434 //===----------------------------------------------------------------------===//
435 
436 class PNaClABIInfo : public ABIInfo {
437  public:
438   PNaClABIInfo(CodeGen::CodeGenTypes &CGT) : ABIInfo(CGT) {}
439 
440   ABIArgInfo classifyReturnType(QualType RetTy) const;
441   ABIArgInfo classifyArgumentType(QualType RetTy) const;
442 
443   virtual void computeInfo(CGFunctionInfo &FI) const;
444   virtual llvm::Value *EmitVAArg(llvm::Value *VAListAddr, QualType Ty,
445                                  CodeGenFunction &CGF) const;
446 };
447 
448 class PNaClTargetCodeGenInfo : public TargetCodeGenInfo {
449  public:
450   PNaClTargetCodeGenInfo(CodeGen::CodeGenTypes &CGT)
451     : TargetCodeGenInfo(new PNaClABIInfo(CGT)) {}
452 };
453 
454 void PNaClABIInfo::computeInfo(CGFunctionInfo &FI) const {
455     FI.getReturnInfo() = classifyReturnType(FI.getReturnType());
456 
457     for (CGFunctionInfo::arg_iterator it = FI.arg_begin(), ie = FI.arg_end();
458          it != ie; ++it)
459       it->info = classifyArgumentType(it->type);
460   }
461 
462 llvm::Value *PNaClABIInfo::EmitVAArg(llvm::Value *VAListAddr, QualType Ty,
463                                        CodeGenFunction &CGF) const {
464   return 0;
465 }
466 
467 /// \brief Classify argument of given type \p Ty.
468 ABIArgInfo PNaClABIInfo::classifyArgumentType(QualType Ty) const {
469   if (isAggregateTypeForABI(Ty)) {
470     if (CGCXXABI::RecordArgABI RAA = getRecordArgABI(Ty, getCXXABI()))
471       return ABIArgInfo::getIndirect(0, RAA == CGCXXABI::RAA_DirectInMemory);
472     return ABIArgInfo::getIndirect(0);
473   } else if (const EnumType *EnumTy = Ty->getAs<EnumType>()) {
474     // Treat an enum type as its underlying type.
475     Ty = EnumTy->getDecl()->getIntegerType();
476   } else if (Ty->isFloatingType()) {
477     // Floating-point types don't go inreg.
478     return ABIArgInfo::getDirect();
479   }
480 
481   return (Ty->isPromotableIntegerType() ?
482           ABIArgInfo::getExtend() : ABIArgInfo::getDirect());
483 }
484 
485 ABIArgInfo PNaClABIInfo::classifyReturnType(QualType RetTy) const {
486   if (RetTy->isVoidType())
487     return ABIArgInfo::getIgnore();
488 
489   // In the PNaCl ABI we always return records/structures on the stack.
490   if (isAggregateTypeForABI(RetTy))
491     return ABIArgInfo::getIndirect(0);
492 
493   // Treat an enum type as its underlying type.
494   if (const EnumType *EnumTy = RetTy->getAs<EnumType>())
495     RetTy = EnumTy->getDecl()->getIntegerType();
496 
497   return (RetTy->isPromotableIntegerType() ?
498           ABIArgInfo::getExtend() : ABIArgInfo::getDirect());
499 }
500 
501 /// IsX86_MMXType - Return true if this is an MMX type.
502 bool IsX86_MMXType(llvm::Type *IRType) {
503   // Return true if the type is an MMX type <2 x i32>, <4 x i16>, or <8 x i8>.
504   return IRType->isVectorTy() && IRType->getPrimitiveSizeInBits() == 64 &&
505     cast<llvm::VectorType>(IRType)->getElementType()->isIntegerTy() &&
506     IRType->getScalarSizeInBits() != 64;
507 }
508 
509 static llvm::Type* X86AdjustInlineAsmType(CodeGen::CodeGenFunction &CGF,
510                                           StringRef Constraint,
511                                           llvm::Type* Ty) {
512   if ((Constraint == "y" || Constraint == "&y") && Ty->isVectorTy()) {
513     if (cast<llvm::VectorType>(Ty)->getBitWidth() != 64) {
514       // Invalid MMX constraint
515       return 0;
516     }
517 
518     return llvm::Type::getX86_MMXTy(CGF.getLLVMContext());
519   }
520 
521   // No operation needed
522   return Ty;
523 }
524 
525 //===----------------------------------------------------------------------===//
526 // X86-32 ABI Implementation
527 //===----------------------------------------------------------------------===//
528 
529 /// \brief Similar to llvm::CCState, but for Clang.
530 struct CCState {
531   CCState(unsigned CC) : CC(CC), FreeRegs(0) {}
532 
533   unsigned CC;
534   unsigned FreeRegs;
535 };
536 
537 /// X86_32ABIInfo - The X86-32 ABI information.
538 class X86_32ABIInfo : public ABIInfo {
539   enum Class {
540     Integer,
541     Float
542   };
543 
544   static const unsigned MinABIStackAlignInBytes = 4;
545 
546   bool IsDarwinVectorABI;
547   bool IsSmallStructInRegABI;
548   bool IsWin32StructABI;
549   unsigned DefaultNumRegisterParameters;
550 
551   static bool isRegisterSize(unsigned Size) {
552     return (Size == 8 || Size == 16 || Size == 32 || Size == 64);
553   }
554 
555   static bool shouldReturnTypeInRegister(QualType Ty, ASTContext &Context,
556                                           unsigned callingConvention);
557 
558   /// getIndirectResult - Give a source type \arg Ty, return a suitable result
559   /// such that the argument will be passed in memory.
560   ABIArgInfo getIndirectResult(QualType Ty, bool ByVal, CCState &State) const;
561 
562   ABIArgInfo getIndirectReturnResult(CCState &State) const;
563 
564   /// \brief Return the alignment to use for the given type on the stack.
565   unsigned getTypeStackAlignInBytes(QualType Ty, unsigned Align) const;
566 
567   Class classify(QualType Ty) const;
568   ABIArgInfo classifyReturnType(QualType RetTy, CCState &State) const;
569   ABIArgInfo classifyArgumentType(QualType RetTy, CCState &State) const;
570   bool shouldUseInReg(QualType Ty, CCState &State, bool &NeedsPadding) const;
571 
572 public:
573 
574   virtual void computeInfo(CGFunctionInfo &FI) const;
575   virtual llvm::Value *EmitVAArg(llvm::Value *VAListAddr, QualType Ty,
576                                  CodeGenFunction &CGF) const;
577 
578   X86_32ABIInfo(CodeGen::CodeGenTypes &CGT, bool d, bool p, bool w,
579                 unsigned r)
580     : ABIInfo(CGT), IsDarwinVectorABI(d), IsSmallStructInRegABI(p),
581       IsWin32StructABI(w), DefaultNumRegisterParameters(r) {}
582 };
583 
584 class X86_32TargetCodeGenInfo : public TargetCodeGenInfo {
585 public:
586   X86_32TargetCodeGenInfo(CodeGen::CodeGenTypes &CGT,
587       bool d, bool p, bool w, unsigned r)
588     :TargetCodeGenInfo(new X86_32ABIInfo(CGT, d, p, w, r)) {}
589 
590   static bool isStructReturnInRegABI(
591       const llvm::Triple &Triple, const CodeGenOptions &Opts);
592 
593   void SetTargetAttributes(const Decl *D, llvm::GlobalValue *GV,
594                            CodeGen::CodeGenModule &CGM) const;
595 
596   int getDwarfEHStackPointer(CodeGen::CodeGenModule &CGM) const {
597     // Darwin uses different dwarf register numbers for EH.
598     if (CGM.getTarget().getTriple().isOSDarwin()) return 5;
599     return 4;
600   }
601 
602   bool initDwarfEHRegSizeTable(CodeGen::CodeGenFunction &CGF,
603                                llvm::Value *Address) const;
604 
605   llvm::Type* adjustInlineAsmType(CodeGen::CodeGenFunction &CGF,
606                                   StringRef Constraint,
607                                   llvm::Type* Ty) const {
608     return X86AdjustInlineAsmType(CGF, Constraint, Ty);
609   }
610 
611   llvm::Constant *getUBSanFunctionSignature(CodeGen::CodeGenModule &CGM) const {
612     unsigned Sig = (0xeb << 0) |  // jmp rel8
613                    (0x06 << 8) |  //           .+0x08
614                    ('F' << 16) |
615                    ('T' << 24);
616     return llvm::ConstantInt::get(CGM.Int32Ty, Sig);
617   }
618 
619 };
620 
621 }
622 
623 /// shouldReturnTypeInRegister - Determine if the given type should be
624 /// passed in a register (for the Darwin ABI).
625 bool X86_32ABIInfo::shouldReturnTypeInRegister(QualType Ty,
626                                                ASTContext &Context,
627                                                unsigned callingConvention) {
628   uint64_t Size = Context.getTypeSize(Ty);
629 
630   // Type must be register sized.
631   if (!isRegisterSize(Size))
632     return false;
633 
634   if (Ty->isVectorType()) {
635     // 64- and 128- bit vectors inside structures are not returned in
636     // registers.
637     if (Size == 64 || Size == 128)
638       return false;
639 
640     return true;
641   }
642 
643   // If this is a builtin, pointer, enum, complex type, member pointer, or
644   // member function pointer it is ok.
645   if (Ty->getAs<BuiltinType>() || Ty->hasPointerRepresentation() ||
646       Ty->isAnyComplexType() || Ty->isEnumeralType() ||
647       Ty->isBlockPointerType() || Ty->isMemberPointerType())
648     return true;
649 
650   // Arrays are treated like records.
651   if (const ConstantArrayType *AT = Context.getAsConstantArrayType(Ty))
652     return shouldReturnTypeInRegister(AT->getElementType(), Context,
653                                       callingConvention);
654 
655   // Otherwise, it must be a record type.
656   const RecordType *RT = Ty->getAs<RecordType>();
657   if (!RT) return false;
658 
659   // FIXME: Traverse bases here too.
660 
661   // For thiscall conventions, structures will never be returned in
662   // a register.  This is for compatibility with the MSVC ABI
663   if (callingConvention == llvm::CallingConv::X86_ThisCall &&
664       RT->isStructureType()) {
665     return false;
666   }
667 
668   // Structure types are passed in register if all fields would be
669   // passed in a register.
670   for (RecordDecl::field_iterator i = RT->getDecl()->field_begin(),
671          e = RT->getDecl()->field_end(); i != e; ++i) {
672     const FieldDecl *FD = *i;
673 
674     // Empty fields are ignored.
675     if (isEmptyField(Context, FD, true))
676       continue;
677 
678     // Check fields recursively.
679     if (!shouldReturnTypeInRegister(FD->getType(), Context,
680                                     callingConvention))
681       return false;
682   }
683   return true;
684 }
685 
686 ABIArgInfo X86_32ABIInfo::getIndirectReturnResult(CCState &State) const {
687   // If the return value is indirect, then the hidden argument is consuming one
688   // integer register.
689   if (State.FreeRegs) {
690     --State.FreeRegs;
691     return ABIArgInfo::getIndirectInReg(/*Align=*/0, /*ByVal=*/false);
692   }
693   return ABIArgInfo::getIndirect(/*Align=*/0, /*ByVal=*/false);
694 }
695 
696 ABIArgInfo X86_32ABIInfo::classifyReturnType(QualType RetTy,
697                                              CCState &State) const {
698   if (RetTy->isVoidType())
699     return ABIArgInfo::getIgnore();
700 
701   if (const VectorType *VT = RetTy->getAs<VectorType>()) {
702     // On Darwin, some vectors are returned in registers.
703     if (IsDarwinVectorABI) {
704       uint64_t Size = getContext().getTypeSize(RetTy);
705 
706       // 128-bit vectors are a special case; they are returned in
707       // registers and we need to make sure to pick a type the LLVM
708       // backend will like.
709       if (Size == 128)
710         return ABIArgInfo::getDirect(llvm::VectorType::get(
711                   llvm::Type::getInt64Ty(getVMContext()), 2));
712 
713       // Always return in register if it fits in a general purpose
714       // register, or if it is 64 bits and has a single element.
715       if ((Size == 8 || Size == 16 || Size == 32) ||
716           (Size == 64 && VT->getNumElements() == 1))
717         return ABIArgInfo::getDirect(llvm::IntegerType::get(getVMContext(),
718                                                             Size));
719 
720       return getIndirectReturnResult(State);
721     }
722 
723     return ABIArgInfo::getDirect();
724   }
725 
726   if (isAggregateTypeForABI(RetTy)) {
727     if (const RecordType *RT = RetTy->getAs<RecordType>()) {
728       if (isRecordReturnIndirect(RT, getCXXABI()))
729         return getIndirectReturnResult(State);
730 
731       // Structures with flexible arrays are always indirect.
732       if (RT->getDecl()->hasFlexibleArrayMember())
733         return getIndirectReturnResult(State);
734     }
735 
736     // If specified, structs and unions are always indirect.
737     if (!IsSmallStructInRegABI && !RetTy->isAnyComplexType())
738       return getIndirectReturnResult(State);
739 
740     // Small structures which are register sized are generally returned
741     // in a register.
742     if (X86_32ABIInfo::shouldReturnTypeInRegister(RetTy, getContext(),
743                                                   State.CC)) {
744       uint64_t Size = getContext().getTypeSize(RetTy);
745 
746       // As a special-case, if the struct is a "single-element" struct, and
747       // the field is of type "float" or "double", return it in a
748       // floating-point register. (MSVC does not apply this special case.)
749       // We apply a similar transformation for pointer types to improve the
750       // quality of the generated IR.
751       if (const Type *SeltTy = isSingleElementStruct(RetTy, getContext()))
752         if ((!IsWin32StructABI && SeltTy->isRealFloatingType())
753             || SeltTy->hasPointerRepresentation())
754           return ABIArgInfo::getDirect(CGT.ConvertType(QualType(SeltTy, 0)));
755 
756       // FIXME: We should be able to narrow this integer in cases with dead
757       // padding.
758       return ABIArgInfo::getDirect(llvm::IntegerType::get(getVMContext(),Size));
759     }
760 
761     return getIndirectReturnResult(State);
762   }
763 
764   // Treat an enum type as its underlying type.
765   if (const EnumType *EnumTy = RetTy->getAs<EnumType>())
766     RetTy = EnumTy->getDecl()->getIntegerType();
767 
768   return (RetTy->isPromotableIntegerType() ?
769           ABIArgInfo::getExtend() : ABIArgInfo::getDirect());
770 }
771 
772 static bool isSSEVectorType(ASTContext &Context, QualType Ty) {
773   return Ty->getAs<VectorType>() && Context.getTypeSize(Ty) == 128;
774 }
775 
776 static bool isRecordWithSSEVectorType(ASTContext &Context, QualType Ty) {
777   const RecordType *RT = Ty->getAs<RecordType>();
778   if (!RT)
779     return 0;
780   const RecordDecl *RD = RT->getDecl();
781 
782   // If this is a C++ record, check the bases first.
783   if (const CXXRecordDecl *CXXRD = dyn_cast<CXXRecordDecl>(RD))
784     for (CXXRecordDecl::base_class_const_iterator i = CXXRD->bases_begin(),
785            e = CXXRD->bases_end(); i != e; ++i)
786       if (!isRecordWithSSEVectorType(Context, i->getType()))
787         return false;
788 
789   for (RecordDecl::field_iterator i = RD->field_begin(), e = RD->field_end();
790        i != e; ++i) {
791     QualType FT = i->getType();
792 
793     if (isSSEVectorType(Context, FT))
794       return true;
795 
796     if (isRecordWithSSEVectorType(Context, FT))
797       return true;
798   }
799 
800   return false;
801 }
802 
803 unsigned X86_32ABIInfo::getTypeStackAlignInBytes(QualType Ty,
804                                                  unsigned Align) const {
805   // Otherwise, if the alignment is less than or equal to the minimum ABI
806   // alignment, just use the default; the backend will handle this.
807   if (Align <= MinABIStackAlignInBytes)
808     return 0; // Use default alignment.
809 
810   // On non-Darwin, the stack type alignment is always 4.
811   if (!IsDarwinVectorABI) {
812     // Set explicit alignment, since we may need to realign the top.
813     return MinABIStackAlignInBytes;
814   }
815 
816   // Otherwise, if the type contains an SSE vector type, the alignment is 16.
817   if (Align >= 16 && (isSSEVectorType(getContext(), Ty) ||
818                       isRecordWithSSEVectorType(getContext(), Ty)))
819     return 16;
820 
821   return MinABIStackAlignInBytes;
822 }
823 
824 ABIArgInfo X86_32ABIInfo::getIndirectResult(QualType Ty, bool ByVal,
825                                             CCState &State) const {
826   if (!ByVal) {
827     if (State.FreeRegs) {
828       --State.FreeRegs; // Non-byval indirects just use one pointer.
829       return ABIArgInfo::getIndirectInReg(0, false);
830     }
831     return ABIArgInfo::getIndirect(0, false);
832   }
833 
834   // Compute the byval alignment.
835   unsigned TypeAlign = getContext().getTypeAlign(Ty) / 8;
836   unsigned StackAlign = getTypeStackAlignInBytes(Ty, TypeAlign);
837   if (StackAlign == 0)
838     return ABIArgInfo::getIndirect(4);
839 
840   // If the stack alignment is less than the type alignment, realign the
841   // argument.
842   if (StackAlign < TypeAlign)
843     return ABIArgInfo::getIndirect(StackAlign, /*ByVal=*/true,
844                                    /*Realign=*/true);
845 
846   return ABIArgInfo::getIndirect(StackAlign);
847 }
848 
849 X86_32ABIInfo::Class X86_32ABIInfo::classify(QualType Ty) const {
850   const Type *T = isSingleElementStruct(Ty, getContext());
851   if (!T)
852     T = Ty.getTypePtr();
853 
854   if (const BuiltinType *BT = T->getAs<BuiltinType>()) {
855     BuiltinType::Kind K = BT->getKind();
856     if (K == BuiltinType::Float || K == BuiltinType::Double)
857       return Float;
858   }
859   return Integer;
860 }
861 
862 bool X86_32ABIInfo::shouldUseInReg(QualType Ty, CCState &State,
863                                    bool &NeedsPadding) const {
864   NeedsPadding = false;
865   Class C = classify(Ty);
866   if (C == Float)
867     return false;
868 
869   unsigned Size = getContext().getTypeSize(Ty);
870   unsigned SizeInRegs = (Size + 31) / 32;
871 
872   if (SizeInRegs == 0)
873     return false;
874 
875   if (SizeInRegs > State.FreeRegs) {
876     State.FreeRegs = 0;
877     return false;
878   }
879 
880   State.FreeRegs -= SizeInRegs;
881 
882   if (State.CC == llvm::CallingConv::X86_FastCall) {
883     if (Size > 32)
884       return false;
885 
886     if (Ty->isIntegralOrEnumerationType())
887       return true;
888 
889     if (Ty->isPointerType())
890       return true;
891 
892     if (Ty->isReferenceType())
893       return true;
894 
895     if (State.FreeRegs)
896       NeedsPadding = true;
897 
898     return false;
899   }
900 
901   return true;
902 }
903 
904 ABIArgInfo X86_32ABIInfo::classifyArgumentType(QualType Ty, CCState &State) const {
905   // FIXME: Set alignment on indirect arguments.
906   if (isAggregateTypeForABI(Ty)) {
907     if (const RecordType *RT = Ty->getAs<RecordType>()) {
908       if (IsWin32StructABI)
909         return getIndirectResult(Ty, true, State);
910 
911       if (CGCXXABI::RecordArgABI RAA = getRecordArgABI(RT, getCXXABI()))
912         return getIndirectResult(Ty, RAA == CGCXXABI::RAA_DirectInMemory,
913                                  State);
914 
915       // Structures with flexible arrays are always indirect.
916       if (RT->getDecl()->hasFlexibleArrayMember())
917         return getIndirectResult(Ty, true, State);
918     }
919 
920     // Ignore empty structs/unions.
921     if (isEmptyRecord(getContext(), Ty, true))
922       return ABIArgInfo::getIgnore();
923 
924     llvm::LLVMContext &LLVMContext = getVMContext();
925     llvm::IntegerType *Int32 = llvm::Type::getInt32Ty(LLVMContext);
926     bool NeedsPadding;
927     if (shouldUseInReg(Ty, State, NeedsPadding)) {
928       unsigned SizeInRegs = (getContext().getTypeSize(Ty) + 31) / 32;
929       SmallVector<llvm::Type*, 3> Elements(SizeInRegs, Int32);
930       llvm::Type *Result = llvm::StructType::get(LLVMContext, Elements);
931       return ABIArgInfo::getDirectInReg(Result);
932     }
933     llvm::IntegerType *PaddingType = NeedsPadding ? Int32 : 0;
934 
935     // Expand small (<= 128-bit) record types when we know that the stack layout
936     // of those arguments will match the struct. This is important because the
937     // LLVM backend isn't smart enough to remove byval, which inhibits many
938     // optimizations.
939     if (getContext().getTypeSize(Ty) <= 4*32 &&
940         canExpandIndirectArgument(Ty, getContext()))
941       return ABIArgInfo::getExpandWithPadding(
942           State.CC == llvm::CallingConv::X86_FastCall, PaddingType);
943 
944     return getIndirectResult(Ty, true, State);
945   }
946 
947   if (const VectorType *VT = Ty->getAs<VectorType>()) {
948     // On Darwin, some vectors are passed in memory, we handle this by passing
949     // it as an i8/i16/i32/i64.
950     if (IsDarwinVectorABI) {
951       uint64_t Size = getContext().getTypeSize(Ty);
952       if ((Size == 8 || Size == 16 || Size == 32) ||
953           (Size == 64 && VT->getNumElements() == 1))
954         return ABIArgInfo::getDirect(llvm::IntegerType::get(getVMContext(),
955                                                             Size));
956     }
957 
958     if (IsX86_MMXType(CGT.ConvertType(Ty)))
959       return ABIArgInfo::getDirect(llvm::IntegerType::get(getVMContext(), 64));
960 
961     return ABIArgInfo::getDirect();
962   }
963 
964 
965   if (const EnumType *EnumTy = Ty->getAs<EnumType>())
966     Ty = EnumTy->getDecl()->getIntegerType();
967 
968   bool NeedsPadding;
969   bool InReg = shouldUseInReg(Ty, State, NeedsPadding);
970 
971   if (Ty->isPromotableIntegerType()) {
972     if (InReg)
973       return ABIArgInfo::getExtendInReg();
974     return ABIArgInfo::getExtend();
975   }
976   if (InReg)
977     return ABIArgInfo::getDirectInReg();
978   return ABIArgInfo::getDirect();
979 }
980 
981 void X86_32ABIInfo::computeInfo(CGFunctionInfo &FI) const {
982   CCState State(FI.getCallingConvention());
983   if (State.CC == llvm::CallingConv::X86_FastCall)
984     State.FreeRegs = 2;
985   else if (FI.getHasRegParm())
986     State.FreeRegs = FI.getRegParm();
987   else
988     State.FreeRegs = DefaultNumRegisterParameters;
989 
990   FI.getReturnInfo() = classifyReturnType(FI.getReturnType(), State);
991 
992   for (CGFunctionInfo::arg_iterator it = FI.arg_begin(), ie = FI.arg_end();
993        it != ie; ++it)
994     it->info = classifyArgumentType(it->type, State);
995 }
996 
997 llvm::Value *X86_32ABIInfo::EmitVAArg(llvm::Value *VAListAddr, QualType Ty,
998                                       CodeGenFunction &CGF) const {
999   llvm::Type *BPP = CGF.Int8PtrPtrTy;
1000 
1001   CGBuilderTy &Builder = CGF.Builder;
1002   llvm::Value *VAListAddrAsBPP = Builder.CreateBitCast(VAListAddr, BPP,
1003                                                        "ap");
1004   llvm::Value *Addr = Builder.CreateLoad(VAListAddrAsBPP, "ap.cur");
1005 
1006   // Compute if the address needs to be aligned
1007   unsigned Align = CGF.getContext().getTypeAlignInChars(Ty).getQuantity();
1008   Align = getTypeStackAlignInBytes(Ty, Align);
1009   Align = std::max(Align, 4U);
1010   if (Align > 4) {
1011     // addr = (addr + align - 1) & -align;
1012     llvm::Value *Offset =
1013       llvm::ConstantInt::get(CGF.Int32Ty, Align - 1);
1014     Addr = CGF.Builder.CreateGEP(Addr, Offset);
1015     llvm::Value *AsInt = CGF.Builder.CreatePtrToInt(Addr,
1016                                                     CGF.Int32Ty);
1017     llvm::Value *Mask = llvm::ConstantInt::get(CGF.Int32Ty, -Align);
1018     Addr = CGF.Builder.CreateIntToPtr(CGF.Builder.CreateAnd(AsInt, Mask),
1019                                       Addr->getType(),
1020                                       "ap.cur.aligned");
1021   }
1022 
1023   llvm::Type *PTy =
1024     llvm::PointerType::getUnqual(CGF.ConvertType(Ty));
1025   llvm::Value *AddrTyped = Builder.CreateBitCast(Addr, PTy);
1026 
1027   uint64_t Offset =
1028     llvm::RoundUpToAlignment(CGF.getContext().getTypeSize(Ty) / 8, Align);
1029   llvm::Value *NextAddr =
1030     Builder.CreateGEP(Addr, llvm::ConstantInt::get(CGF.Int32Ty, Offset),
1031                       "ap.next");
1032   Builder.CreateStore(NextAddr, VAListAddrAsBPP);
1033 
1034   return AddrTyped;
1035 }
1036 
1037 void X86_32TargetCodeGenInfo::SetTargetAttributes(const Decl *D,
1038                                                   llvm::GlobalValue *GV,
1039                                             CodeGen::CodeGenModule &CGM) const {
1040   if (const FunctionDecl *FD = dyn_cast<FunctionDecl>(D)) {
1041     if (FD->hasAttr<X86ForceAlignArgPointerAttr>()) {
1042       // Get the LLVM function.
1043       llvm::Function *Fn = cast<llvm::Function>(GV);
1044 
1045       // Now add the 'alignstack' attribute with a value of 16.
1046       llvm::AttrBuilder B;
1047       B.addStackAlignmentAttr(16);
1048       Fn->addAttributes(llvm::AttributeSet::FunctionIndex,
1049                       llvm::AttributeSet::get(CGM.getLLVMContext(),
1050                                               llvm::AttributeSet::FunctionIndex,
1051                                               B));
1052     }
1053   }
1054 }
1055 
1056 bool X86_32TargetCodeGenInfo::initDwarfEHRegSizeTable(
1057                                                CodeGen::CodeGenFunction &CGF,
1058                                                llvm::Value *Address) const {
1059   CodeGen::CGBuilderTy &Builder = CGF.Builder;
1060 
1061   llvm::Value *Four8 = llvm::ConstantInt::get(CGF.Int8Ty, 4);
1062 
1063   // 0-7 are the eight integer registers;  the order is different
1064   //   on Darwin (for EH), but the range is the same.
1065   // 8 is %eip.
1066   AssignToArrayRange(Builder, Address, Four8, 0, 8);
1067 
1068   if (CGF.CGM.getTarget().getTriple().isOSDarwin()) {
1069     // 12-16 are st(0..4).  Not sure why we stop at 4.
1070     // These have size 16, which is sizeof(long double) on
1071     // platforms with 8-byte alignment for that type.
1072     llvm::Value *Sixteen8 = llvm::ConstantInt::get(CGF.Int8Ty, 16);
1073     AssignToArrayRange(Builder, Address, Sixteen8, 12, 16);
1074 
1075   } else {
1076     // 9 is %eflags, which doesn't get a size on Darwin for some
1077     // reason.
1078     Builder.CreateStore(Four8, Builder.CreateConstInBoundsGEP1_32(Address, 9));
1079 
1080     // 11-16 are st(0..5).  Not sure why we stop at 5.
1081     // These have size 12, which is sizeof(long double) on
1082     // platforms with 4-byte alignment for that type.
1083     llvm::Value *Twelve8 = llvm::ConstantInt::get(CGF.Int8Ty, 12);
1084     AssignToArrayRange(Builder, Address, Twelve8, 11, 16);
1085   }
1086 
1087   return false;
1088 }
1089 
1090 //===----------------------------------------------------------------------===//
1091 // X86-64 ABI Implementation
1092 //===----------------------------------------------------------------------===//
1093 
1094 
1095 namespace {
1096 /// X86_64ABIInfo - The X86_64 ABI information.
1097 class X86_64ABIInfo : public ABIInfo {
1098   enum Class {
1099     Integer = 0,
1100     SSE,
1101     SSEUp,
1102     X87,
1103     X87Up,
1104     ComplexX87,
1105     NoClass,
1106     Memory
1107   };
1108 
1109   /// merge - Implement the X86_64 ABI merging algorithm.
1110   ///
1111   /// Merge an accumulating classification \arg Accum with a field
1112   /// classification \arg Field.
1113   ///
1114   /// \param Accum - The accumulating classification. This should
1115   /// always be either NoClass or the result of a previous merge
1116   /// call. In addition, this should never be Memory (the caller
1117   /// should just return Memory for the aggregate).
1118   static Class merge(Class Accum, Class Field);
1119 
1120   /// postMerge - Implement the X86_64 ABI post merging algorithm.
1121   ///
1122   /// Post merger cleanup, reduces a malformed Hi and Lo pair to
1123   /// final MEMORY or SSE classes when necessary.
1124   ///
1125   /// \param AggregateSize - The size of the current aggregate in
1126   /// the classification process.
1127   ///
1128   /// \param Lo - The classification for the parts of the type
1129   /// residing in the low word of the containing object.
1130   ///
1131   /// \param Hi - The classification for the parts of the type
1132   /// residing in the higher words of the containing object.
1133   ///
1134   void postMerge(unsigned AggregateSize, Class &Lo, Class &Hi) const;
1135 
1136   /// classify - Determine the x86_64 register classes in which the
1137   /// given type T should be passed.
1138   ///
1139   /// \param Lo - The classification for the parts of the type
1140   /// residing in the low word of the containing object.
1141   ///
1142   /// \param Hi - The classification for the parts of the type
1143   /// residing in the high word of the containing object.
1144   ///
1145   /// \param OffsetBase - The bit offset of this type in the
1146   /// containing object.  Some parameters are classified different
1147   /// depending on whether they straddle an eightbyte boundary.
1148   ///
1149   /// \param isNamedArg - Whether the argument in question is a "named"
1150   /// argument, as used in AMD64-ABI 3.5.7.
1151   ///
1152   /// If a word is unused its result will be NoClass; if a type should
1153   /// be passed in Memory then at least the classification of \arg Lo
1154   /// will be Memory.
1155   ///
1156   /// The \arg Lo class will be NoClass iff the argument is ignored.
1157   ///
1158   /// If the \arg Lo class is ComplexX87, then the \arg Hi class will
1159   /// also be ComplexX87.
1160   void classify(QualType T, uint64_t OffsetBase, Class &Lo, Class &Hi,
1161                 bool isNamedArg) const;
1162 
1163   llvm::Type *GetByteVectorType(QualType Ty) const;
1164   llvm::Type *GetSSETypeAtOffset(llvm::Type *IRType,
1165                                  unsigned IROffset, QualType SourceTy,
1166                                  unsigned SourceOffset) const;
1167   llvm::Type *GetINTEGERTypeAtOffset(llvm::Type *IRType,
1168                                      unsigned IROffset, QualType SourceTy,
1169                                      unsigned SourceOffset) const;
1170 
1171   /// getIndirectResult - Give a source type \arg Ty, return a suitable result
1172   /// such that the argument will be returned in memory.
1173   ABIArgInfo getIndirectReturnResult(QualType Ty) const;
1174 
1175   /// getIndirectResult - Give a source type \arg Ty, return a suitable result
1176   /// such that the argument will be passed in memory.
1177   ///
1178   /// \param freeIntRegs - The number of free integer registers remaining
1179   /// available.
1180   ABIArgInfo getIndirectResult(QualType Ty, unsigned freeIntRegs) const;
1181 
1182   ABIArgInfo classifyReturnType(QualType RetTy) const;
1183 
1184   ABIArgInfo classifyArgumentType(QualType Ty,
1185                                   unsigned freeIntRegs,
1186                                   unsigned &neededInt,
1187                                   unsigned &neededSSE,
1188                                   bool isNamedArg) const;
1189 
1190   bool IsIllegalVectorType(QualType Ty) const;
1191 
1192   /// The 0.98 ABI revision clarified a lot of ambiguities,
1193   /// unfortunately in ways that were not always consistent with
1194   /// certain previous compilers.  In particular, platforms which
1195   /// required strict binary compatibility with older versions of GCC
1196   /// may need to exempt themselves.
1197   bool honorsRevision0_98() const {
1198     return !getTarget().getTriple().isOSDarwin();
1199   }
1200 
1201   bool HasAVX;
1202   // Some ABIs (e.g. X32 ABI and Native Client OS) use 32 bit pointers on
1203   // 64-bit hardware.
1204   bool Has64BitPointers;
1205 
1206 public:
1207   X86_64ABIInfo(CodeGen::CodeGenTypes &CGT, bool hasavx) :
1208       ABIInfo(CGT), HasAVX(hasavx),
1209       Has64BitPointers(CGT.getDataLayout().getPointerSize(0) == 8) {
1210   }
1211 
1212   bool isPassedUsingAVXType(QualType type) const {
1213     unsigned neededInt, neededSSE;
1214     // The freeIntRegs argument doesn't matter here.
1215     ABIArgInfo info = classifyArgumentType(type, 0, neededInt, neededSSE,
1216                                            /*isNamedArg*/true);
1217     if (info.isDirect()) {
1218       llvm::Type *ty = info.getCoerceToType();
1219       if (llvm::VectorType *vectorTy = dyn_cast_or_null<llvm::VectorType>(ty))
1220         return (vectorTy->getBitWidth() > 128);
1221     }
1222     return false;
1223   }
1224 
1225   virtual void computeInfo(CGFunctionInfo &FI) const;
1226 
1227   virtual llvm::Value *EmitVAArg(llvm::Value *VAListAddr, QualType Ty,
1228                                  CodeGenFunction &CGF) const;
1229 };
1230 
1231 /// WinX86_64ABIInfo - The Windows X86_64 ABI information.
1232 class WinX86_64ABIInfo : public ABIInfo {
1233 
1234   ABIArgInfo classify(QualType Ty, bool IsReturnType) const;
1235 
1236 public:
1237   WinX86_64ABIInfo(CodeGen::CodeGenTypes &CGT) : ABIInfo(CGT) {}
1238 
1239   virtual void computeInfo(CGFunctionInfo &FI) const;
1240 
1241   virtual llvm::Value *EmitVAArg(llvm::Value *VAListAddr, QualType Ty,
1242                                  CodeGenFunction &CGF) const;
1243 };
1244 
1245 class X86_64TargetCodeGenInfo : public TargetCodeGenInfo {
1246 public:
1247   X86_64TargetCodeGenInfo(CodeGen::CodeGenTypes &CGT, bool HasAVX)
1248       : TargetCodeGenInfo(new X86_64ABIInfo(CGT, HasAVX)) {}
1249 
1250   const X86_64ABIInfo &getABIInfo() const {
1251     return static_cast<const X86_64ABIInfo&>(TargetCodeGenInfo::getABIInfo());
1252   }
1253 
1254   int getDwarfEHStackPointer(CodeGen::CodeGenModule &CGM) const {
1255     return 7;
1256   }
1257 
1258   bool initDwarfEHRegSizeTable(CodeGen::CodeGenFunction &CGF,
1259                                llvm::Value *Address) const {
1260     llvm::Value *Eight8 = llvm::ConstantInt::get(CGF.Int8Ty, 8);
1261 
1262     // 0-15 are the 16 integer registers.
1263     // 16 is %rip.
1264     AssignToArrayRange(CGF.Builder, Address, Eight8, 0, 16);
1265     return false;
1266   }
1267 
1268   llvm::Type* adjustInlineAsmType(CodeGen::CodeGenFunction &CGF,
1269                                   StringRef Constraint,
1270                                   llvm::Type* Ty) const {
1271     return X86AdjustInlineAsmType(CGF, Constraint, Ty);
1272   }
1273 
1274   bool isNoProtoCallVariadic(const CallArgList &args,
1275                              const FunctionNoProtoType *fnType) const {
1276     // The default CC on x86-64 sets %al to the number of SSA
1277     // registers used, and GCC sets this when calling an unprototyped
1278     // function, so we override the default behavior.  However, don't do
1279     // that when AVX types are involved: the ABI explicitly states it is
1280     // undefined, and it doesn't work in practice because of how the ABI
1281     // defines varargs anyway.
1282     if (fnType->getCallConv() == CC_C) {
1283       bool HasAVXType = false;
1284       for (CallArgList::const_iterator
1285              it = args.begin(), ie = args.end(); it != ie; ++it) {
1286         if (getABIInfo().isPassedUsingAVXType(it->Ty)) {
1287           HasAVXType = true;
1288           break;
1289         }
1290       }
1291 
1292       if (!HasAVXType)
1293         return true;
1294     }
1295 
1296     return TargetCodeGenInfo::isNoProtoCallVariadic(args, fnType);
1297   }
1298 
1299   llvm::Constant *getUBSanFunctionSignature(CodeGen::CodeGenModule &CGM) const {
1300     unsigned Sig = (0xeb << 0) |  // jmp rel8
1301                    (0x0a << 8) |  //           .+0x0c
1302                    ('F' << 16) |
1303                    ('T' << 24);
1304     return llvm::ConstantInt::get(CGM.Int32Ty, Sig);
1305   }
1306 
1307 };
1308 
1309 static std::string qualifyWindowsLibrary(llvm::StringRef Lib) {
1310   // If the argument does not end in .lib, automatically add the suffix. This
1311   // matches the behavior of MSVC.
1312   std::string ArgStr = Lib;
1313   if (!Lib.endswith_lower(".lib"))
1314     ArgStr += ".lib";
1315   return ArgStr;
1316 }
1317 
1318 class WinX86_32TargetCodeGenInfo : public X86_32TargetCodeGenInfo {
1319 public:
1320   WinX86_32TargetCodeGenInfo(CodeGen::CodeGenTypes &CGT,
1321         bool d, bool p, bool w, unsigned RegParms)
1322     : X86_32TargetCodeGenInfo(CGT, d, p, w, RegParms) {}
1323 
1324   void getDependentLibraryOption(llvm::StringRef Lib,
1325                                  llvm::SmallString<24> &Opt) const {
1326     Opt = "/DEFAULTLIB:";
1327     Opt += qualifyWindowsLibrary(Lib);
1328   }
1329 
1330   void getDetectMismatchOption(llvm::StringRef Name,
1331                                llvm::StringRef Value,
1332                                llvm::SmallString<32> &Opt) const {
1333     Opt = "/FAILIFMISMATCH:\"" + Name.str() + "=" + Value.str() + "\"";
1334   }
1335 };
1336 
1337 class WinX86_64TargetCodeGenInfo : public TargetCodeGenInfo {
1338 public:
1339   WinX86_64TargetCodeGenInfo(CodeGen::CodeGenTypes &CGT)
1340     : TargetCodeGenInfo(new WinX86_64ABIInfo(CGT)) {}
1341 
1342   int getDwarfEHStackPointer(CodeGen::CodeGenModule &CGM) const {
1343     return 7;
1344   }
1345 
1346   bool initDwarfEHRegSizeTable(CodeGen::CodeGenFunction &CGF,
1347                                llvm::Value *Address) const {
1348     llvm::Value *Eight8 = llvm::ConstantInt::get(CGF.Int8Ty, 8);
1349 
1350     // 0-15 are the 16 integer registers.
1351     // 16 is %rip.
1352     AssignToArrayRange(CGF.Builder, Address, Eight8, 0, 16);
1353     return false;
1354   }
1355 
1356   void getDependentLibraryOption(llvm::StringRef Lib,
1357                                  llvm::SmallString<24> &Opt) const {
1358     Opt = "/DEFAULTLIB:";
1359     Opt += qualifyWindowsLibrary(Lib);
1360   }
1361 
1362   void getDetectMismatchOption(llvm::StringRef Name,
1363                                llvm::StringRef Value,
1364                                llvm::SmallString<32> &Opt) const {
1365     Opt = "/FAILIFMISMATCH:\"" + Name.str() + "=" + Value.str() + "\"";
1366   }
1367 };
1368 
1369 }
1370 
1371 void X86_64ABIInfo::postMerge(unsigned AggregateSize, Class &Lo,
1372                               Class &Hi) const {
1373   // AMD64-ABI 3.2.3p2: Rule 5. Then a post merger cleanup is done:
1374   //
1375   // (a) If one of the classes is Memory, the whole argument is passed in
1376   //     memory.
1377   //
1378   // (b) If X87UP is not preceded by X87, the whole argument is passed in
1379   //     memory.
1380   //
1381   // (c) If the size of the aggregate exceeds two eightbytes and the first
1382   //     eightbyte isn't SSE or any other eightbyte isn't SSEUP, the whole
1383   //     argument is passed in memory. NOTE: This is necessary to keep the
1384   //     ABI working for processors that don't support the __m256 type.
1385   //
1386   // (d) If SSEUP is not preceded by SSE or SSEUP, it is converted to SSE.
1387   //
1388   // Some of these are enforced by the merging logic.  Others can arise
1389   // only with unions; for example:
1390   //   union { _Complex double; unsigned; }
1391   //
1392   // Note that clauses (b) and (c) were added in 0.98.
1393   //
1394   if (Hi == Memory)
1395     Lo = Memory;
1396   if (Hi == X87Up && Lo != X87 && honorsRevision0_98())
1397     Lo = Memory;
1398   if (AggregateSize > 128 && (Lo != SSE || Hi != SSEUp))
1399     Lo = Memory;
1400   if (Hi == SSEUp && Lo != SSE)
1401     Hi = SSE;
1402 }
1403 
1404 X86_64ABIInfo::Class X86_64ABIInfo::merge(Class Accum, Class Field) {
1405   // AMD64-ABI 3.2.3p2: Rule 4. Each field of an object is
1406   // classified recursively so that always two fields are
1407   // considered. The resulting class is calculated according to
1408   // the classes of the fields in the eightbyte:
1409   //
1410   // (a) If both classes are equal, this is the resulting class.
1411   //
1412   // (b) If one of the classes is NO_CLASS, the resulting class is
1413   // the other class.
1414   //
1415   // (c) If one of the classes is MEMORY, the result is the MEMORY
1416   // class.
1417   //
1418   // (d) If one of the classes is INTEGER, the result is the
1419   // INTEGER.
1420   //
1421   // (e) If one of the classes is X87, X87UP, COMPLEX_X87 class,
1422   // MEMORY is used as class.
1423   //
1424   // (f) Otherwise class SSE is used.
1425 
1426   // Accum should never be memory (we should have returned) or
1427   // ComplexX87 (because this cannot be passed in a structure).
1428   assert((Accum != Memory && Accum != ComplexX87) &&
1429          "Invalid accumulated classification during merge.");
1430   if (Accum == Field || Field == NoClass)
1431     return Accum;
1432   if (Field == Memory)
1433     return Memory;
1434   if (Accum == NoClass)
1435     return Field;
1436   if (Accum == Integer || Field == Integer)
1437     return Integer;
1438   if (Field == X87 || Field == X87Up || Field == ComplexX87 ||
1439       Accum == X87 || Accum == X87Up)
1440     return Memory;
1441   return SSE;
1442 }
1443 
1444 void X86_64ABIInfo::classify(QualType Ty, uint64_t OffsetBase,
1445                              Class &Lo, Class &Hi, bool isNamedArg) const {
1446   // FIXME: This code can be simplified by introducing a simple value class for
1447   // Class pairs with appropriate constructor methods for the various
1448   // situations.
1449 
1450   // FIXME: Some of the split computations are wrong; unaligned vectors
1451   // shouldn't be passed in registers for example, so there is no chance they
1452   // can straddle an eightbyte. Verify & simplify.
1453 
1454   Lo = Hi = NoClass;
1455 
1456   Class &Current = OffsetBase < 64 ? Lo : Hi;
1457   Current = Memory;
1458 
1459   if (const BuiltinType *BT = Ty->getAs<BuiltinType>()) {
1460     BuiltinType::Kind k = BT->getKind();
1461 
1462     if (k == BuiltinType::Void) {
1463       Current = NoClass;
1464     } else if (k == BuiltinType::Int128 || k == BuiltinType::UInt128) {
1465       Lo = Integer;
1466       Hi = Integer;
1467     } else if (k >= BuiltinType::Bool && k <= BuiltinType::LongLong) {
1468       Current = Integer;
1469     } else if ((k == BuiltinType::Float || k == BuiltinType::Double) ||
1470                (k == BuiltinType::LongDouble &&
1471                 getTarget().getTriple().isOSNaCl())) {
1472       Current = SSE;
1473     } else if (k == BuiltinType::LongDouble) {
1474       Lo = X87;
1475       Hi = X87Up;
1476     }
1477     // FIXME: _Decimal32 and _Decimal64 are SSE.
1478     // FIXME: _float128 and _Decimal128 are (SSE, SSEUp).
1479     return;
1480   }
1481 
1482   if (const EnumType *ET = Ty->getAs<EnumType>()) {
1483     // Classify the underlying integer type.
1484     classify(ET->getDecl()->getIntegerType(), OffsetBase, Lo, Hi, isNamedArg);
1485     return;
1486   }
1487 
1488   if (Ty->hasPointerRepresentation()) {
1489     Current = Integer;
1490     return;
1491   }
1492 
1493   if (Ty->isMemberPointerType()) {
1494     if (Ty->isMemberFunctionPointerType() && Has64BitPointers)
1495       Lo = Hi = Integer;
1496     else
1497       Current = Integer;
1498     return;
1499   }
1500 
1501   if (const VectorType *VT = Ty->getAs<VectorType>()) {
1502     uint64_t Size = getContext().getTypeSize(VT);
1503     if (Size == 32) {
1504       // gcc passes all <4 x char>, <2 x short>, <1 x int>, <1 x
1505       // float> as integer.
1506       Current = Integer;
1507 
1508       // If this type crosses an eightbyte boundary, it should be
1509       // split.
1510       uint64_t EB_Real = (OffsetBase) / 64;
1511       uint64_t EB_Imag = (OffsetBase + Size - 1) / 64;
1512       if (EB_Real != EB_Imag)
1513         Hi = Lo;
1514     } else if (Size == 64) {
1515       // gcc passes <1 x double> in memory. :(
1516       if (VT->getElementType()->isSpecificBuiltinType(BuiltinType::Double))
1517         return;
1518 
1519       // gcc passes <1 x long long> as INTEGER.
1520       if (VT->getElementType()->isSpecificBuiltinType(BuiltinType::LongLong) ||
1521           VT->getElementType()->isSpecificBuiltinType(BuiltinType::ULongLong) ||
1522           VT->getElementType()->isSpecificBuiltinType(BuiltinType::Long) ||
1523           VT->getElementType()->isSpecificBuiltinType(BuiltinType::ULong))
1524         Current = Integer;
1525       else
1526         Current = SSE;
1527 
1528       // If this type crosses an eightbyte boundary, it should be
1529       // split.
1530       if (OffsetBase && OffsetBase != 64)
1531         Hi = Lo;
1532     } else if (Size == 128 || (HasAVX && isNamedArg && Size == 256)) {
1533       // Arguments of 256-bits are split into four eightbyte chunks. The
1534       // least significant one belongs to class SSE and all the others to class
1535       // SSEUP. The original Lo and Hi design considers that types can't be
1536       // greater than 128-bits, so a 64-bit split in Hi and Lo makes sense.
1537       // This design isn't correct for 256-bits, but since there're no cases
1538       // where the upper parts would need to be inspected, avoid adding
1539       // complexity and just consider Hi to match the 64-256 part.
1540       //
1541       // Note that per 3.5.7 of AMD64-ABI, 256-bit args are only passed in
1542       // registers if they are "named", i.e. not part of the "..." of a
1543       // variadic function.
1544       Lo = SSE;
1545       Hi = SSEUp;
1546     }
1547     return;
1548   }
1549 
1550   if (const ComplexType *CT = Ty->getAs<ComplexType>()) {
1551     QualType ET = getContext().getCanonicalType(CT->getElementType());
1552 
1553     uint64_t Size = getContext().getTypeSize(Ty);
1554     if (ET->isIntegralOrEnumerationType()) {
1555       if (Size <= 64)
1556         Current = Integer;
1557       else if (Size <= 128)
1558         Lo = Hi = Integer;
1559     } else if (ET == getContext().FloatTy)
1560       Current = SSE;
1561     else if (ET == getContext().DoubleTy ||
1562              (ET == getContext().LongDoubleTy &&
1563               getTarget().getTriple().isOSNaCl()))
1564       Lo = Hi = SSE;
1565     else if (ET == getContext().LongDoubleTy)
1566       Current = ComplexX87;
1567 
1568     // If this complex type crosses an eightbyte boundary then it
1569     // should be split.
1570     uint64_t EB_Real = (OffsetBase) / 64;
1571     uint64_t EB_Imag = (OffsetBase + getContext().getTypeSize(ET)) / 64;
1572     if (Hi == NoClass && EB_Real != EB_Imag)
1573       Hi = Lo;
1574 
1575     return;
1576   }
1577 
1578   if (const ConstantArrayType *AT = getContext().getAsConstantArrayType(Ty)) {
1579     // Arrays are treated like structures.
1580 
1581     uint64_t Size = getContext().getTypeSize(Ty);
1582 
1583     // AMD64-ABI 3.2.3p2: Rule 1. If the size of an object is larger
1584     // than four eightbytes, ..., it has class MEMORY.
1585     if (Size > 256)
1586       return;
1587 
1588     // AMD64-ABI 3.2.3p2: Rule 1. If ..., or it contains unaligned
1589     // fields, it has class MEMORY.
1590     //
1591     // Only need to check alignment of array base.
1592     if (OffsetBase % getContext().getTypeAlign(AT->getElementType()))
1593       return;
1594 
1595     // Otherwise implement simplified merge. We could be smarter about
1596     // this, but it isn't worth it and would be harder to verify.
1597     Current = NoClass;
1598     uint64_t EltSize = getContext().getTypeSize(AT->getElementType());
1599     uint64_t ArraySize = AT->getSize().getZExtValue();
1600 
1601     // The only case a 256-bit wide vector could be used is when the array
1602     // contains a single 256-bit element. Since Lo and Hi logic isn't extended
1603     // to work for sizes wider than 128, early check and fallback to memory.
1604     if (Size > 128 && EltSize != 256)
1605       return;
1606 
1607     for (uint64_t i=0, Offset=OffsetBase; i<ArraySize; ++i, Offset += EltSize) {
1608       Class FieldLo, FieldHi;
1609       classify(AT->getElementType(), Offset, FieldLo, FieldHi, isNamedArg);
1610       Lo = merge(Lo, FieldLo);
1611       Hi = merge(Hi, FieldHi);
1612       if (Lo == Memory || Hi == Memory)
1613         break;
1614     }
1615 
1616     postMerge(Size, Lo, Hi);
1617     assert((Hi != SSEUp || Lo == SSE) && "Invalid SSEUp array classification.");
1618     return;
1619   }
1620 
1621   if (const RecordType *RT = Ty->getAs<RecordType>()) {
1622     uint64_t Size = getContext().getTypeSize(Ty);
1623 
1624     // AMD64-ABI 3.2.3p2: Rule 1. If the size of an object is larger
1625     // than four eightbytes, ..., it has class MEMORY.
1626     if (Size > 256)
1627       return;
1628 
1629     // AMD64-ABI 3.2.3p2: Rule 2. If a C++ object has either a non-trivial
1630     // copy constructor or a non-trivial destructor, it is passed by invisible
1631     // reference.
1632     if (getRecordArgABI(RT, getCXXABI()))
1633       return;
1634 
1635     const RecordDecl *RD = RT->getDecl();
1636 
1637     // Assume variable sized types are passed in memory.
1638     if (RD->hasFlexibleArrayMember())
1639       return;
1640 
1641     const ASTRecordLayout &Layout = getContext().getASTRecordLayout(RD);
1642 
1643     // Reset Lo class, this will be recomputed.
1644     Current = NoClass;
1645 
1646     // If this is a C++ record, classify the bases first.
1647     if (const CXXRecordDecl *CXXRD = dyn_cast<CXXRecordDecl>(RD)) {
1648       for (CXXRecordDecl::base_class_const_iterator i = CXXRD->bases_begin(),
1649              e = CXXRD->bases_end(); i != e; ++i) {
1650         assert(!i->isVirtual() && !i->getType()->isDependentType() &&
1651                "Unexpected base class!");
1652         const CXXRecordDecl *Base =
1653           cast<CXXRecordDecl>(i->getType()->getAs<RecordType>()->getDecl());
1654 
1655         // Classify this field.
1656         //
1657         // AMD64-ABI 3.2.3p2: Rule 3. If the size of the aggregate exceeds a
1658         // single eightbyte, each is classified separately. Each eightbyte gets
1659         // initialized to class NO_CLASS.
1660         Class FieldLo, FieldHi;
1661         uint64_t Offset =
1662           OffsetBase + getContext().toBits(Layout.getBaseClassOffset(Base));
1663         classify(i->getType(), Offset, FieldLo, FieldHi, isNamedArg);
1664         Lo = merge(Lo, FieldLo);
1665         Hi = merge(Hi, FieldHi);
1666         if (Lo == Memory || Hi == Memory)
1667           break;
1668       }
1669     }
1670 
1671     // Classify the fields one at a time, merging the results.
1672     unsigned idx = 0;
1673     for (RecordDecl::field_iterator i = RD->field_begin(), e = RD->field_end();
1674            i != e; ++i, ++idx) {
1675       uint64_t Offset = OffsetBase + Layout.getFieldOffset(idx);
1676       bool BitField = i->isBitField();
1677 
1678       // AMD64-ABI 3.2.3p2: Rule 1. If the size of an object is larger than
1679       // four eightbytes, or it contains unaligned fields, it has class MEMORY.
1680       //
1681       // The only case a 256-bit wide vector could be used is when the struct
1682       // contains a single 256-bit element. Since Lo and Hi logic isn't extended
1683       // to work for sizes wider than 128, early check and fallback to memory.
1684       //
1685       if (Size > 128 && getContext().getTypeSize(i->getType()) != 256) {
1686         Lo = Memory;
1687         return;
1688       }
1689       // Note, skip this test for bit-fields, see below.
1690       if (!BitField && Offset % getContext().getTypeAlign(i->getType())) {
1691         Lo = Memory;
1692         return;
1693       }
1694 
1695       // Classify this field.
1696       //
1697       // AMD64-ABI 3.2.3p2: Rule 3. If the size of the aggregate
1698       // exceeds a single eightbyte, each is classified
1699       // separately. Each eightbyte gets initialized to class
1700       // NO_CLASS.
1701       Class FieldLo, FieldHi;
1702 
1703       // Bit-fields require special handling, they do not force the
1704       // structure to be passed in memory even if unaligned, and
1705       // therefore they can straddle an eightbyte.
1706       if (BitField) {
1707         // Ignore padding bit-fields.
1708         if (i->isUnnamedBitfield())
1709           continue;
1710 
1711         uint64_t Offset = OffsetBase + Layout.getFieldOffset(idx);
1712         uint64_t Size = i->getBitWidthValue(getContext());
1713 
1714         uint64_t EB_Lo = Offset / 64;
1715         uint64_t EB_Hi = (Offset + Size - 1) / 64;
1716 
1717         if (EB_Lo) {
1718           assert(EB_Hi == EB_Lo && "Invalid classification, type > 16 bytes.");
1719           FieldLo = NoClass;
1720           FieldHi = Integer;
1721         } else {
1722           FieldLo = Integer;
1723           FieldHi = EB_Hi ? Integer : NoClass;
1724         }
1725       } else
1726         classify(i->getType(), Offset, FieldLo, FieldHi, isNamedArg);
1727       Lo = merge(Lo, FieldLo);
1728       Hi = merge(Hi, FieldHi);
1729       if (Lo == Memory || Hi == Memory)
1730         break;
1731     }
1732 
1733     postMerge(Size, Lo, Hi);
1734   }
1735 }
1736 
1737 ABIArgInfo X86_64ABIInfo::getIndirectReturnResult(QualType Ty) const {
1738   // If this is a scalar LLVM value then assume LLVM will pass it in the right
1739   // place naturally.
1740   if (!isAggregateTypeForABI(Ty)) {
1741     // Treat an enum type as its underlying type.
1742     if (const EnumType *EnumTy = Ty->getAs<EnumType>())
1743       Ty = EnumTy->getDecl()->getIntegerType();
1744 
1745     return (Ty->isPromotableIntegerType() ?
1746             ABIArgInfo::getExtend() : ABIArgInfo::getDirect());
1747   }
1748 
1749   return ABIArgInfo::getIndirect(0);
1750 }
1751 
1752 bool X86_64ABIInfo::IsIllegalVectorType(QualType Ty) const {
1753   if (const VectorType *VecTy = Ty->getAs<VectorType>()) {
1754     uint64_t Size = getContext().getTypeSize(VecTy);
1755     unsigned LargestVector = HasAVX ? 256 : 128;
1756     if (Size <= 64 || Size > LargestVector)
1757       return true;
1758   }
1759 
1760   return false;
1761 }
1762 
1763 ABIArgInfo X86_64ABIInfo::getIndirectResult(QualType Ty,
1764                                             unsigned freeIntRegs) const {
1765   // If this is a scalar LLVM value then assume LLVM will pass it in the right
1766   // place naturally.
1767   //
1768   // This assumption is optimistic, as there could be free registers available
1769   // when we need to pass this argument in memory, and LLVM could try to pass
1770   // the argument in the free register. This does not seem to happen currently,
1771   // but this code would be much safer if we could mark the argument with
1772   // 'onstack'. See PR12193.
1773   if (!isAggregateTypeForABI(Ty) && !IsIllegalVectorType(Ty)) {
1774     // Treat an enum type as its underlying type.
1775     if (const EnumType *EnumTy = Ty->getAs<EnumType>())
1776       Ty = EnumTy->getDecl()->getIntegerType();
1777 
1778     return (Ty->isPromotableIntegerType() ?
1779             ABIArgInfo::getExtend() : ABIArgInfo::getDirect());
1780   }
1781 
1782   if (CGCXXABI::RecordArgABI RAA = getRecordArgABI(Ty, getCXXABI()))
1783     return ABIArgInfo::getIndirect(0, RAA == CGCXXABI::RAA_DirectInMemory);
1784 
1785   // Compute the byval alignment. We specify the alignment of the byval in all
1786   // cases so that the mid-level optimizer knows the alignment of the byval.
1787   unsigned Align = std::max(getContext().getTypeAlign(Ty) / 8, 8U);
1788 
1789   // Attempt to avoid passing indirect results using byval when possible. This
1790   // is important for good codegen.
1791   //
1792   // We do this by coercing the value into a scalar type which the backend can
1793   // handle naturally (i.e., without using byval).
1794   //
1795   // For simplicity, we currently only do this when we have exhausted all of the
1796   // free integer registers. Doing this when there are free integer registers
1797   // would require more care, as we would have to ensure that the coerced value
1798   // did not claim the unused register. That would require either reording the
1799   // arguments to the function (so that any subsequent inreg values came first),
1800   // or only doing this optimization when there were no following arguments that
1801   // might be inreg.
1802   //
1803   // We currently expect it to be rare (particularly in well written code) for
1804   // arguments to be passed on the stack when there are still free integer
1805   // registers available (this would typically imply large structs being passed
1806   // by value), so this seems like a fair tradeoff for now.
1807   //
1808   // We can revisit this if the backend grows support for 'onstack' parameter
1809   // attributes. See PR12193.
1810   if (freeIntRegs == 0) {
1811     uint64_t Size = getContext().getTypeSize(Ty);
1812 
1813     // If this type fits in an eightbyte, coerce it into the matching integral
1814     // type, which will end up on the stack (with alignment 8).
1815     if (Align == 8 && Size <= 64)
1816       return ABIArgInfo::getDirect(llvm::IntegerType::get(getVMContext(),
1817                                                           Size));
1818   }
1819 
1820   return ABIArgInfo::getIndirect(Align);
1821 }
1822 
1823 /// GetByteVectorType - The ABI specifies that a value should be passed in an
1824 /// full vector XMM/YMM register.  Pick an LLVM IR type that will be passed as a
1825 /// vector register.
1826 llvm::Type *X86_64ABIInfo::GetByteVectorType(QualType Ty) const {
1827   llvm::Type *IRType = CGT.ConvertType(Ty);
1828 
1829   // Wrapper structs that just contain vectors are passed just like vectors,
1830   // strip them off if present.
1831   llvm::StructType *STy = dyn_cast<llvm::StructType>(IRType);
1832   while (STy && STy->getNumElements() == 1) {
1833     IRType = STy->getElementType(0);
1834     STy = dyn_cast<llvm::StructType>(IRType);
1835   }
1836 
1837   // If the preferred type is a 16-byte vector, prefer to pass it.
1838   if (llvm::VectorType *VT = dyn_cast<llvm::VectorType>(IRType)){
1839     llvm::Type *EltTy = VT->getElementType();
1840     unsigned BitWidth = VT->getBitWidth();
1841     if ((BitWidth >= 128 && BitWidth <= 256) &&
1842         (EltTy->isFloatTy() || EltTy->isDoubleTy() ||
1843          EltTy->isIntegerTy(8) || EltTy->isIntegerTy(16) ||
1844          EltTy->isIntegerTy(32) || EltTy->isIntegerTy(64) ||
1845          EltTy->isIntegerTy(128)))
1846       return VT;
1847   }
1848 
1849   return llvm::VectorType::get(llvm::Type::getDoubleTy(getVMContext()), 2);
1850 }
1851 
1852 /// BitsContainNoUserData - Return true if the specified [start,end) bit range
1853 /// is known to either be off the end of the specified type or being in
1854 /// alignment padding.  The user type specified is known to be at most 128 bits
1855 /// in size, and have passed through X86_64ABIInfo::classify with a successful
1856 /// classification that put one of the two halves in the INTEGER class.
1857 ///
1858 /// It is conservatively correct to return false.
1859 static bool BitsContainNoUserData(QualType Ty, unsigned StartBit,
1860                                   unsigned EndBit, ASTContext &Context) {
1861   // If the bytes being queried are off the end of the type, there is no user
1862   // data hiding here.  This handles analysis of builtins, vectors and other
1863   // types that don't contain interesting padding.
1864   unsigned TySize = (unsigned)Context.getTypeSize(Ty);
1865   if (TySize <= StartBit)
1866     return true;
1867 
1868   if (const ConstantArrayType *AT = Context.getAsConstantArrayType(Ty)) {
1869     unsigned EltSize = (unsigned)Context.getTypeSize(AT->getElementType());
1870     unsigned NumElts = (unsigned)AT->getSize().getZExtValue();
1871 
1872     // Check each element to see if the element overlaps with the queried range.
1873     for (unsigned i = 0; i != NumElts; ++i) {
1874       // If the element is after the span we care about, then we're done..
1875       unsigned EltOffset = i*EltSize;
1876       if (EltOffset >= EndBit) break;
1877 
1878       unsigned EltStart = EltOffset < StartBit ? StartBit-EltOffset :0;
1879       if (!BitsContainNoUserData(AT->getElementType(), EltStart,
1880                                  EndBit-EltOffset, Context))
1881         return false;
1882     }
1883     // If it overlaps no elements, then it is safe to process as padding.
1884     return true;
1885   }
1886 
1887   if (const RecordType *RT = Ty->getAs<RecordType>()) {
1888     const RecordDecl *RD = RT->getDecl();
1889     const ASTRecordLayout &Layout = Context.getASTRecordLayout(RD);
1890 
1891     // If this is a C++ record, check the bases first.
1892     if (const CXXRecordDecl *CXXRD = dyn_cast<CXXRecordDecl>(RD)) {
1893       for (CXXRecordDecl::base_class_const_iterator i = CXXRD->bases_begin(),
1894            e = CXXRD->bases_end(); i != e; ++i) {
1895         assert(!i->isVirtual() && !i->getType()->isDependentType() &&
1896                "Unexpected base class!");
1897         const CXXRecordDecl *Base =
1898           cast<CXXRecordDecl>(i->getType()->getAs<RecordType>()->getDecl());
1899 
1900         // If the base is after the span we care about, ignore it.
1901         unsigned BaseOffset = Context.toBits(Layout.getBaseClassOffset(Base));
1902         if (BaseOffset >= EndBit) continue;
1903 
1904         unsigned BaseStart = BaseOffset < StartBit ? StartBit-BaseOffset :0;
1905         if (!BitsContainNoUserData(i->getType(), BaseStart,
1906                                    EndBit-BaseOffset, Context))
1907           return false;
1908       }
1909     }
1910 
1911     // Verify that no field has data that overlaps the region of interest.  Yes
1912     // this could be sped up a lot by being smarter about queried fields,
1913     // however we're only looking at structs up to 16 bytes, so we don't care
1914     // much.
1915     unsigned idx = 0;
1916     for (RecordDecl::field_iterator i = RD->field_begin(), e = RD->field_end();
1917          i != e; ++i, ++idx) {
1918       unsigned FieldOffset = (unsigned)Layout.getFieldOffset(idx);
1919 
1920       // If we found a field after the region we care about, then we're done.
1921       if (FieldOffset >= EndBit) break;
1922 
1923       unsigned FieldStart = FieldOffset < StartBit ? StartBit-FieldOffset :0;
1924       if (!BitsContainNoUserData(i->getType(), FieldStart, EndBit-FieldOffset,
1925                                  Context))
1926         return false;
1927     }
1928 
1929     // If nothing in this record overlapped the area of interest, then we're
1930     // clean.
1931     return true;
1932   }
1933 
1934   return false;
1935 }
1936 
1937 /// ContainsFloatAtOffset - Return true if the specified LLVM IR type has a
1938 /// float member at the specified offset.  For example, {int,{float}} has a
1939 /// float at offset 4.  It is conservatively correct for this routine to return
1940 /// false.
1941 static bool ContainsFloatAtOffset(llvm::Type *IRType, unsigned IROffset,
1942                                   const llvm::DataLayout &TD) {
1943   // Base case if we find a float.
1944   if (IROffset == 0 && IRType->isFloatTy())
1945     return true;
1946 
1947   // If this is a struct, recurse into the field at the specified offset.
1948   if (llvm::StructType *STy = dyn_cast<llvm::StructType>(IRType)) {
1949     const llvm::StructLayout *SL = TD.getStructLayout(STy);
1950     unsigned Elt = SL->getElementContainingOffset(IROffset);
1951     IROffset -= SL->getElementOffset(Elt);
1952     return ContainsFloatAtOffset(STy->getElementType(Elt), IROffset, TD);
1953   }
1954 
1955   // If this is an array, recurse into the field at the specified offset.
1956   if (llvm::ArrayType *ATy = dyn_cast<llvm::ArrayType>(IRType)) {
1957     llvm::Type *EltTy = ATy->getElementType();
1958     unsigned EltSize = TD.getTypeAllocSize(EltTy);
1959     IROffset -= IROffset/EltSize*EltSize;
1960     return ContainsFloatAtOffset(EltTy, IROffset, TD);
1961   }
1962 
1963   return false;
1964 }
1965 
1966 
1967 /// GetSSETypeAtOffset - Return a type that will be passed by the backend in the
1968 /// low 8 bytes of an XMM register, corresponding to the SSE class.
1969 llvm::Type *X86_64ABIInfo::
1970 GetSSETypeAtOffset(llvm::Type *IRType, unsigned IROffset,
1971                    QualType SourceTy, unsigned SourceOffset) const {
1972   // The only three choices we have are either double, <2 x float>, or float. We
1973   // pass as float if the last 4 bytes is just padding.  This happens for
1974   // structs that contain 3 floats.
1975   if (BitsContainNoUserData(SourceTy, SourceOffset*8+32,
1976                             SourceOffset*8+64, getContext()))
1977     return llvm::Type::getFloatTy(getVMContext());
1978 
1979   // We want to pass as <2 x float> if the LLVM IR type contains a float at
1980   // offset+0 and offset+4.  Walk the LLVM IR type to find out if this is the
1981   // case.
1982   if (ContainsFloatAtOffset(IRType, IROffset, getDataLayout()) &&
1983       ContainsFloatAtOffset(IRType, IROffset+4, getDataLayout()))
1984     return llvm::VectorType::get(llvm::Type::getFloatTy(getVMContext()), 2);
1985 
1986   return llvm::Type::getDoubleTy(getVMContext());
1987 }
1988 
1989 
1990 /// GetINTEGERTypeAtOffset - The ABI specifies that a value should be passed in
1991 /// an 8-byte GPR.  This means that we either have a scalar or we are talking
1992 /// about the high or low part of an up-to-16-byte struct.  This routine picks
1993 /// the best LLVM IR type to represent this, which may be i64 or may be anything
1994 /// else that the backend will pass in a GPR that works better (e.g. i8, %foo*,
1995 /// etc).
1996 ///
1997 /// PrefType is an LLVM IR type that corresponds to (part of) the IR type for
1998 /// the source type.  IROffset is an offset in bytes into the LLVM IR type that
1999 /// the 8-byte value references.  PrefType may be null.
2000 ///
2001 /// SourceTy is the source level type for the entire argument.  SourceOffset is
2002 /// an offset into this that we're processing (which is always either 0 or 8).
2003 ///
2004 llvm::Type *X86_64ABIInfo::
2005 GetINTEGERTypeAtOffset(llvm::Type *IRType, unsigned IROffset,
2006                        QualType SourceTy, unsigned SourceOffset) const {
2007   // If we're dealing with an un-offset LLVM IR type, then it means that we're
2008   // returning an 8-byte unit starting with it.  See if we can safely use it.
2009   if (IROffset == 0) {
2010     // Pointers and int64's always fill the 8-byte unit.
2011     if ((isa<llvm::PointerType>(IRType) && Has64BitPointers) ||
2012         IRType->isIntegerTy(64))
2013       return IRType;
2014 
2015     // If we have a 1/2/4-byte integer, we can use it only if the rest of the
2016     // goodness in the source type is just tail padding.  This is allowed to
2017     // kick in for struct {double,int} on the int, but not on
2018     // struct{double,int,int} because we wouldn't return the second int.  We
2019     // have to do this analysis on the source type because we can't depend on
2020     // unions being lowered a specific way etc.
2021     if (IRType->isIntegerTy(8) || IRType->isIntegerTy(16) ||
2022         IRType->isIntegerTy(32) ||
2023         (isa<llvm::PointerType>(IRType) && !Has64BitPointers)) {
2024       unsigned BitWidth = isa<llvm::PointerType>(IRType) ? 32 :
2025           cast<llvm::IntegerType>(IRType)->getBitWidth();
2026 
2027       if (BitsContainNoUserData(SourceTy, SourceOffset*8+BitWidth,
2028                                 SourceOffset*8+64, getContext()))
2029         return IRType;
2030     }
2031   }
2032 
2033   if (llvm::StructType *STy = dyn_cast<llvm::StructType>(IRType)) {
2034     // If this is a struct, recurse into the field at the specified offset.
2035     const llvm::StructLayout *SL = getDataLayout().getStructLayout(STy);
2036     if (IROffset < SL->getSizeInBytes()) {
2037       unsigned FieldIdx = SL->getElementContainingOffset(IROffset);
2038       IROffset -= SL->getElementOffset(FieldIdx);
2039 
2040       return GetINTEGERTypeAtOffset(STy->getElementType(FieldIdx), IROffset,
2041                                     SourceTy, SourceOffset);
2042     }
2043   }
2044 
2045   if (llvm::ArrayType *ATy = dyn_cast<llvm::ArrayType>(IRType)) {
2046     llvm::Type *EltTy = ATy->getElementType();
2047     unsigned EltSize = getDataLayout().getTypeAllocSize(EltTy);
2048     unsigned EltOffset = IROffset/EltSize*EltSize;
2049     return GetINTEGERTypeAtOffset(EltTy, IROffset-EltOffset, SourceTy,
2050                                   SourceOffset);
2051   }
2052 
2053   // Okay, we don't have any better idea of what to pass, so we pass this in an
2054   // integer register that isn't too big to fit the rest of the struct.
2055   unsigned TySizeInBytes =
2056     (unsigned)getContext().getTypeSizeInChars(SourceTy).getQuantity();
2057 
2058   assert(TySizeInBytes != SourceOffset && "Empty field?");
2059 
2060   // It is always safe to classify this as an integer type up to i64 that
2061   // isn't larger than the structure.
2062   return llvm::IntegerType::get(getVMContext(),
2063                                 std::min(TySizeInBytes-SourceOffset, 8U)*8);
2064 }
2065 
2066 
2067 /// GetX86_64ByValArgumentPair - Given a high and low type that can ideally
2068 /// be used as elements of a two register pair to pass or return, return a
2069 /// first class aggregate to represent them.  For example, if the low part of
2070 /// a by-value argument should be passed as i32* and the high part as float,
2071 /// return {i32*, float}.
2072 static llvm::Type *
2073 GetX86_64ByValArgumentPair(llvm::Type *Lo, llvm::Type *Hi,
2074                            const llvm::DataLayout &TD) {
2075   // In order to correctly satisfy the ABI, we need to the high part to start
2076   // at offset 8.  If the high and low parts we inferred are both 4-byte types
2077   // (e.g. i32 and i32) then the resultant struct type ({i32,i32}) won't have
2078   // the second element at offset 8.  Check for this:
2079   unsigned LoSize = (unsigned)TD.getTypeAllocSize(Lo);
2080   unsigned HiAlign = TD.getABITypeAlignment(Hi);
2081   unsigned HiStart = llvm::DataLayout::RoundUpAlignment(LoSize, HiAlign);
2082   assert(HiStart != 0 && HiStart <= 8 && "Invalid x86-64 argument pair!");
2083 
2084   // To handle this, we have to increase the size of the low part so that the
2085   // second element will start at an 8 byte offset.  We can't increase the size
2086   // of the second element because it might make us access off the end of the
2087   // struct.
2088   if (HiStart != 8) {
2089     // There are only two sorts of types the ABI generation code can produce for
2090     // the low part of a pair that aren't 8 bytes in size: float or i8/i16/i32.
2091     // Promote these to a larger type.
2092     if (Lo->isFloatTy())
2093       Lo = llvm::Type::getDoubleTy(Lo->getContext());
2094     else {
2095       assert(Lo->isIntegerTy() && "Invalid/unknown lo type");
2096       Lo = llvm::Type::getInt64Ty(Lo->getContext());
2097     }
2098   }
2099 
2100   llvm::StructType *Result = llvm::StructType::get(Lo, Hi, NULL);
2101 
2102 
2103   // Verify that the second element is at an 8-byte offset.
2104   assert(TD.getStructLayout(Result)->getElementOffset(1) == 8 &&
2105          "Invalid x86-64 argument pair!");
2106   return Result;
2107 }
2108 
2109 ABIArgInfo X86_64ABIInfo::
2110 classifyReturnType(QualType RetTy) const {
2111   // AMD64-ABI 3.2.3p4: Rule 1. Classify the return type with the
2112   // classification algorithm.
2113   X86_64ABIInfo::Class Lo, Hi;
2114   classify(RetTy, 0, Lo, Hi, /*isNamedArg*/ true);
2115 
2116   // Check some invariants.
2117   assert((Hi != Memory || Lo == Memory) && "Invalid memory classification.");
2118   assert((Hi != SSEUp || Lo == SSE) && "Invalid SSEUp classification.");
2119 
2120   llvm::Type *ResType = 0;
2121   switch (Lo) {
2122   case NoClass:
2123     if (Hi == NoClass)
2124       return ABIArgInfo::getIgnore();
2125     // If the low part is just padding, it takes no register, leave ResType
2126     // null.
2127     assert((Hi == SSE || Hi == Integer || Hi == X87Up) &&
2128            "Unknown missing lo part");
2129     break;
2130 
2131   case SSEUp:
2132   case X87Up:
2133     llvm_unreachable("Invalid classification for lo word.");
2134 
2135     // AMD64-ABI 3.2.3p4: Rule 2. Types of class memory are returned via
2136     // hidden argument.
2137   case Memory:
2138     return getIndirectReturnResult(RetTy);
2139 
2140     // AMD64-ABI 3.2.3p4: Rule 3. If the class is INTEGER, the next
2141     // available register of the sequence %rax, %rdx is used.
2142   case Integer:
2143     ResType = GetINTEGERTypeAtOffset(CGT.ConvertType(RetTy), 0, RetTy, 0);
2144 
2145     // If we have a sign or zero extended integer, make sure to return Extend
2146     // so that the parameter gets the right LLVM IR attributes.
2147     if (Hi == NoClass && isa<llvm::IntegerType>(ResType)) {
2148       // Treat an enum type as its underlying type.
2149       if (const EnumType *EnumTy = RetTy->getAs<EnumType>())
2150         RetTy = EnumTy->getDecl()->getIntegerType();
2151 
2152       if (RetTy->isIntegralOrEnumerationType() &&
2153           RetTy->isPromotableIntegerType())
2154         return ABIArgInfo::getExtend();
2155     }
2156     break;
2157 
2158     // AMD64-ABI 3.2.3p4: Rule 4. If the class is SSE, the next
2159     // available SSE register of the sequence %xmm0, %xmm1 is used.
2160   case SSE:
2161     ResType = GetSSETypeAtOffset(CGT.ConvertType(RetTy), 0, RetTy, 0);
2162     break;
2163 
2164     // AMD64-ABI 3.2.3p4: Rule 6. If the class is X87, the value is
2165     // returned on the X87 stack in %st0 as 80-bit x87 number.
2166   case X87:
2167     ResType = llvm::Type::getX86_FP80Ty(getVMContext());
2168     break;
2169 
2170     // AMD64-ABI 3.2.3p4: Rule 8. If the class is COMPLEX_X87, the real
2171     // part of the value is returned in %st0 and the imaginary part in
2172     // %st1.
2173   case ComplexX87:
2174     assert(Hi == ComplexX87 && "Unexpected ComplexX87 classification.");
2175     ResType = llvm::StructType::get(llvm::Type::getX86_FP80Ty(getVMContext()),
2176                                     llvm::Type::getX86_FP80Ty(getVMContext()),
2177                                     NULL);
2178     break;
2179   }
2180 
2181   llvm::Type *HighPart = 0;
2182   switch (Hi) {
2183     // Memory was handled previously and X87 should
2184     // never occur as a hi class.
2185   case Memory:
2186   case X87:
2187     llvm_unreachable("Invalid classification for hi word.");
2188 
2189   case ComplexX87: // Previously handled.
2190   case NoClass:
2191     break;
2192 
2193   case Integer:
2194     HighPart = GetINTEGERTypeAtOffset(CGT.ConvertType(RetTy), 8, RetTy, 8);
2195     if (Lo == NoClass)  // Return HighPart at offset 8 in memory.
2196       return ABIArgInfo::getDirect(HighPart, 8);
2197     break;
2198   case SSE:
2199     HighPart = GetSSETypeAtOffset(CGT.ConvertType(RetTy), 8, RetTy, 8);
2200     if (Lo == NoClass)  // Return HighPart at offset 8 in memory.
2201       return ABIArgInfo::getDirect(HighPart, 8);
2202     break;
2203 
2204     // AMD64-ABI 3.2.3p4: Rule 5. If the class is SSEUP, the eightbyte
2205     // is passed in the next available eightbyte chunk if the last used
2206     // vector register.
2207     //
2208     // SSEUP should always be preceded by SSE, just widen.
2209   case SSEUp:
2210     assert(Lo == SSE && "Unexpected SSEUp classification.");
2211     ResType = GetByteVectorType(RetTy);
2212     break;
2213 
2214     // AMD64-ABI 3.2.3p4: Rule 7. If the class is X87UP, the value is
2215     // returned together with the previous X87 value in %st0.
2216   case X87Up:
2217     // If X87Up is preceded by X87, we don't need to do
2218     // anything. However, in some cases with unions it may not be
2219     // preceded by X87. In such situations we follow gcc and pass the
2220     // extra bits in an SSE reg.
2221     if (Lo != X87) {
2222       HighPart = GetSSETypeAtOffset(CGT.ConvertType(RetTy), 8, RetTy, 8);
2223       if (Lo == NoClass)  // Return HighPart at offset 8 in memory.
2224         return ABIArgInfo::getDirect(HighPart, 8);
2225     }
2226     break;
2227   }
2228 
2229   // If a high part was specified, merge it together with the low part.  It is
2230   // known to pass in the high eightbyte of the result.  We do this by forming a
2231   // first class struct aggregate with the high and low part: {low, high}
2232   if (HighPart)
2233     ResType = GetX86_64ByValArgumentPair(ResType, HighPart, getDataLayout());
2234 
2235   return ABIArgInfo::getDirect(ResType);
2236 }
2237 
2238 ABIArgInfo X86_64ABIInfo::classifyArgumentType(
2239   QualType Ty, unsigned freeIntRegs, unsigned &neededInt, unsigned &neededSSE,
2240   bool isNamedArg)
2241   const
2242 {
2243   X86_64ABIInfo::Class Lo, Hi;
2244   classify(Ty, 0, Lo, Hi, isNamedArg);
2245 
2246   // Check some invariants.
2247   // FIXME: Enforce these by construction.
2248   assert((Hi != Memory || Lo == Memory) && "Invalid memory classification.");
2249   assert((Hi != SSEUp || Lo == SSE) && "Invalid SSEUp classification.");
2250 
2251   neededInt = 0;
2252   neededSSE = 0;
2253   llvm::Type *ResType = 0;
2254   switch (Lo) {
2255   case NoClass:
2256     if (Hi == NoClass)
2257       return ABIArgInfo::getIgnore();
2258     // If the low part is just padding, it takes no register, leave ResType
2259     // null.
2260     assert((Hi == SSE || Hi == Integer || Hi == X87Up) &&
2261            "Unknown missing lo part");
2262     break;
2263 
2264     // AMD64-ABI 3.2.3p3: Rule 1. If the class is MEMORY, pass the argument
2265     // on the stack.
2266   case Memory:
2267 
2268     // AMD64-ABI 3.2.3p3: Rule 5. If the class is X87, X87UP or
2269     // COMPLEX_X87, it is passed in memory.
2270   case X87:
2271   case ComplexX87:
2272     if (getRecordArgABI(Ty, getCXXABI()) == CGCXXABI::RAA_Indirect)
2273       ++neededInt;
2274     return getIndirectResult(Ty, freeIntRegs);
2275 
2276   case SSEUp:
2277   case X87Up:
2278     llvm_unreachable("Invalid classification for lo word.");
2279 
2280     // AMD64-ABI 3.2.3p3: Rule 2. If the class is INTEGER, the next
2281     // available register of the sequence %rdi, %rsi, %rdx, %rcx, %r8
2282     // and %r9 is used.
2283   case Integer:
2284     ++neededInt;
2285 
2286     // Pick an 8-byte type based on the preferred type.
2287     ResType = GetINTEGERTypeAtOffset(CGT.ConvertType(Ty), 0, Ty, 0);
2288 
2289     // If we have a sign or zero extended integer, make sure to return Extend
2290     // so that the parameter gets the right LLVM IR attributes.
2291     if (Hi == NoClass && isa<llvm::IntegerType>(ResType)) {
2292       // Treat an enum type as its underlying type.
2293       if (const EnumType *EnumTy = Ty->getAs<EnumType>())
2294         Ty = EnumTy->getDecl()->getIntegerType();
2295 
2296       if (Ty->isIntegralOrEnumerationType() &&
2297           Ty->isPromotableIntegerType())
2298         return ABIArgInfo::getExtend();
2299     }
2300 
2301     break;
2302 
2303     // AMD64-ABI 3.2.3p3: Rule 3. If the class is SSE, the next
2304     // available SSE register is used, the registers are taken in the
2305     // order from %xmm0 to %xmm7.
2306   case SSE: {
2307     llvm::Type *IRType = CGT.ConvertType(Ty);
2308     ResType = GetSSETypeAtOffset(IRType, 0, Ty, 0);
2309     ++neededSSE;
2310     break;
2311   }
2312   }
2313 
2314   llvm::Type *HighPart = 0;
2315   switch (Hi) {
2316     // Memory was handled previously, ComplexX87 and X87 should
2317     // never occur as hi classes, and X87Up must be preceded by X87,
2318     // which is passed in memory.
2319   case Memory:
2320   case X87:
2321   case ComplexX87:
2322     llvm_unreachable("Invalid classification for hi word.");
2323 
2324   case NoClass: break;
2325 
2326   case Integer:
2327     ++neededInt;
2328     // Pick an 8-byte type based on the preferred type.
2329     HighPart = GetINTEGERTypeAtOffset(CGT.ConvertType(Ty), 8, Ty, 8);
2330 
2331     if (Lo == NoClass)  // Pass HighPart at offset 8 in memory.
2332       return ABIArgInfo::getDirect(HighPart, 8);
2333     break;
2334 
2335     // X87Up generally doesn't occur here (long double is passed in
2336     // memory), except in situations involving unions.
2337   case X87Up:
2338   case SSE:
2339     HighPart = GetSSETypeAtOffset(CGT.ConvertType(Ty), 8, Ty, 8);
2340 
2341     if (Lo == NoClass)  // Pass HighPart at offset 8 in memory.
2342       return ABIArgInfo::getDirect(HighPart, 8);
2343 
2344     ++neededSSE;
2345     break;
2346 
2347     // AMD64-ABI 3.2.3p3: Rule 4. If the class is SSEUP, the
2348     // eightbyte is passed in the upper half of the last used SSE
2349     // register.  This only happens when 128-bit vectors are passed.
2350   case SSEUp:
2351     assert(Lo == SSE && "Unexpected SSEUp classification");
2352     ResType = GetByteVectorType(Ty);
2353     break;
2354   }
2355 
2356   // If a high part was specified, merge it together with the low part.  It is
2357   // known to pass in the high eightbyte of the result.  We do this by forming a
2358   // first class struct aggregate with the high and low part: {low, high}
2359   if (HighPart)
2360     ResType = GetX86_64ByValArgumentPair(ResType, HighPart, getDataLayout());
2361 
2362   return ABIArgInfo::getDirect(ResType);
2363 }
2364 
2365 void X86_64ABIInfo::computeInfo(CGFunctionInfo &FI) const {
2366 
2367   FI.getReturnInfo() = classifyReturnType(FI.getReturnType());
2368 
2369   // Keep track of the number of assigned registers.
2370   unsigned freeIntRegs = 6, freeSSERegs = 8;
2371 
2372   // If the return value is indirect, then the hidden argument is consuming one
2373   // integer register.
2374   if (FI.getReturnInfo().isIndirect())
2375     --freeIntRegs;
2376 
2377   bool isVariadic = FI.isVariadic();
2378   unsigned numRequiredArgs = 0;
2379   if (isVariadic)
2380     numRequiredArgs = FI.getRequiredArgs().getNumRequiredArgs();
2381 
2382   // AMD64-ABI 3.2.3p3: Once arguments are classified, the registers
2383   // get assigned (in left-to-right order) for passing as follows...
2384   for (CGFunctionInfo::arg_iterator it = FI.arg_begin(), ie = FI.arg_end();
2385        it != ie; ++it) {
2386     bool isNamedArg = true;
2387     if (isVariadic)
2388       isNamedArg = (it - FI.arg_begin()) <
2389                     static_cast<signed>(numRequiredArgs);
2390 
2391     unsigned neededInt, neededSSE;
2392     it->info = classifyArgumentType(it->type, freeIntRegs, neededInt,
2393                                     neededSSE, isNamedArg);
2394 
2395     // AMD64-ABI 3.2.3p3: If there are no registers available for any
2396     // eightbyte of an argument, the whole argument is passed on the
2397     // stack. If registers have already been assigned for some
2398     // eightbytes of such an argument, the assignments get reverted.
2399     if (freeIntRegs >= neededInt && freeSSERegs >= neededSSE) {
2400       freeIntRegs -= neededInt;
2401       freeSSERegs -= neededSSE;
2402     } else {
2403       it->info = getIndirectResult(it->type, freeIntRegs);
2404     }
2405   }
2406 }
2407 
2408 static llvm::Value *EmitVAArgFromMemory(llvm::Value *VAListAddr,
2409                                         QualType Ty,
2410                                         CodeGenFunction &CGF) {
2411   llvm::Value *overflow_arg_area_p =
2412     CGF.Builder.CreateStructGEP(VAListAddr, 2, "overflow_arg_area_p");
2413   llvm::Value *overflow_arg_area =
2414     CGF.Builder.CreateLoad(overflow_arg_area_p, "overflow_arg_area");
2415 
2416   // AMD64-ABI 3.5.7p5: Step 7. Align l->overflow_arg_area upwards to a 16
2417   // byte boundary if alignment needed by type exceeds 8 byte boundary.
2418   // It isn't stated explicitly in the standard, but in practice we use
2419   // alignment greater than 16 where necessary.
2420   uint64_t Align = CGF.getContext().getTypeAlign(Ty) / 8;
2421   if (Align > 8) {
2422     // overflow_arg_area = (overflow_arg_area + align - 1) & -align;
2423     llvm::Value *Offset =
2424       llvm::ConstantInt::get(CGF.Int64Ty, Align - 1);
2425     overflow_arg_area = CGF.Builder.CreateGEP(overflow_arg_area, Offset);
2426     llvm::Value *AsInt = CGF.Builder.CreatePtrToInt(overflow_arg_area,
2427                                                     CGF.Int64Ty);
2428     llvm::Value *Mask = llvm::ConstantInt::get(CGF.Int64Ty, -(uint64_t)Align);
2429     overflow_arg_area =
2430       CGF.Builder.CreateIntToPtr(CGF.Builder.CreateAnd(AsInt, Mask),
2431                                  overflow_arg_area->getType(),
2432                                  "overflow_arg_area.align");
2433   }
2434 
2435   // AMD64-ABI 3.5.7p5: Step 8. Fetch type from l->overflow_arg_area.
2436   llvm::Type *LTy = CGF.ConvertTypeForMem(Ty);
2437   llvm::Value *Res =
2438     CGF.Builder.CreateBitCast(overflow_arg_area,
2439                               llvm::PointerType::getUnqual(LTy));
2440 
2441   // AMD64-ABI 3.5.7p5: Step 9. Set l->overflow_arg_area to:
2442   // l->overflow_arg_area + sizeof(type).
2443   // AMD64-ABI 3.5.7p5: Step 10. Align l->overflow_arg_area upwards to
2444   // an 8 byte boundary.
2445 
2446   uint64_t SizeInBytes = (CGF.getContext().getTypeSize(Ty) + 7) / 8;
2447   llvm::Value *Offset =
2448       llvm::ConstantInt::get(CGF.Int32Ty, (SizeInBytes + 7)  & ~7);
2449   overflow_arg_area = CGF.Builder.CreateGEP(overflow_arg_area, Offset,
2450                                             "overflow_arg_area.next");
2451   CGF.Builder.CreateStore(overflow_arg_area, overflow_arg_area_p);
2452 
2453   // AMD64-ABI 3.5.7p5: Step 11. Return the fetched type.
2454   return Res;
2455 }
2456 
2457 llvm::Value *X86_64ABIInfo::EmitVAArg(llvm::Value *VAListAddr, QualType Ty,
2458                                       CodeGenFunction &CGF) const {
2459   // Assume that va_list type is correct; should be pointer to LLVM type:
2460   // struct {
2461   //   i32 gp_offset;
2462   //   i32 fp_offset;
2463   //   i8* overflow_arg_area;
2464   //   i8* reg_save_area;
2465   // };
2466   unsigned neededInt, neededSSE;
2467 
2468   Ty = CGF.getContext().getCanonicalType(Ty);
2469   ABIArgInfo AI = classifyArgumentType(Ty, 0, neededInt, neededSSE,
2470                                        /*isNamedArg*/false);
2471 
2472   // AMD64-ABI 3.5.7p5: Step 1. Determine whether type may be passed
2473   // in the registers. If not go to step 7.
2474   if (!neededInt && !neededSSE)
2475     return EmitVAArgFromMemory(VAListAddr, Ty, CGF);
2476 
2477   // AMD64-ABI 3.5.7p5: Step 2. Compute num_gp to hold the number of
2478   // general purpose registers needed to pass type and num_fp to hold
2479   // the number of floating point registers needed.
2480 
2481   // AMD64-ABI 3.5.7p5: Step 3. Verify whether arguments fit into
2482   // registers. In the case: l->gp_offset > 48 - num_gp * 8 or
2483   // l->fp_offset > 304 - num_fp * 16 go to step 7.
2484   //
2485   // NOTE: 304 is a typo, there are (6 * 8 + 8 * 16) = 176 bytes of
2486   // register save space).
2487 
2488   llvm::Value *InRegs = 0;
2489   llvm::Value *gp_offset_p = 0, *gp_offset = 0;
2490   llvm::Value *fp_offset_p = 0, *fp_offset = 0;
2491   if (neededInt) {
2492     gp_offset_p = CGF.Builder.CreateStructGEP(VAListAddr, 0, "gp_offset_p");
2493     gp_offset = CGF.Builder.CreateLoad(gp_offset_p, "gp_offset");
2494     InRegs = llvm::ConstantInt::get(CGF.Int32Ty, 48 - neededInt * 8);
2495     InRegs = CGF.Builder.CreateICmpULE(gp_offset, InRegs, "fits_in_gp");
2496   }
2497 
2498   if (neededSSE) {
2499     fp_offset_p = CGF.Builder.CreateStructGEP(VAListAddr, 1, "fp_offset_p");
2500     fp_offset = CGF.Builder.CreateLoad(fp_offset_p, "fp_offset");
2501     llvm::Value *FitsInFP =
2502       llvm::ConstantInt::get(CGF.Int32Ty, 176 - neededSSE * 16);
2503     FitsInFP = CGF.Builder.CreateICmpULE(fp_offset, FitsInFP, "fits_in_fp");
2504     InRegs = InRegs ? CGF.Builder.CreateAnd(InRegs, FitsInFP) : FitsInFP;
2505   }
2506 
2507   llvm::BasicBlock *InRegBlock = CGF.createBasicBlock("vaarg.in_reg");
2508   llvm::BasicBlock *InMemBlock = CGF.createBasicBlock("vaarg.in_mem");
2509   llvm::BasicBlock *ContBlock = CGF.createBasicBlock("vaarg.end");
2510   CGF.Builder.CreateCondBr(InRegs, InRegBlock, InMemBlock);
2511 
2512   // Emit code to load the value if it was passed in registers.
2513 
2514   CGF.EmitBlock(InRegBlock);
2515 
2516   // AMD64-ABI 3.5.7p5: Step 4. Fetch type from l->reg_save_area with
2517   // an offset of l->gp_offset and/or l->fp_offset. This may require
2518   // copying to a temporary location in case the parameter is passed
2519   // in different register classes or requires an alignment greater
2520   // than 8 for general purpose registers and 16 for XMM registers.
2521   //
2522   // FIXME: This really results in shameful code when we end up needing to
2523   // collect arguments from different places; often what should result in a
2524   // simple assembling of a structure from scattered addresses has many more
2525   // loads than necessary. Can we clean this up?
2526   llvm::Type *LTy = CGF.ConvertTypeForMem(Ty);
2527   llvm::Value *RegAddr =
2528     CGF.Builder.CreateLoad(CGF.Builder.CreateStructGEP(VAListAddr, 3),
2529                            "reg_save_area");
2530   if (neededInt && neededSSE) {
2531     // FIXME: Cleanup.
2532     assert(AI.isDirect() && "Unexpected ABI info for mixed regs");
2533     llvm::StructType *ST = cast<llvm::StructType>(AI.getCoerceToType());
2534     llvm::Value *Tmp = CGF.CreateMemTemp(Ty);
2535     Tmp = CGF.Builder.CreateBitCast(Tmp, ST->getPointerTo());
2536     assert(ST->getNumElements() == 2 && "Unexpected ABI info for mixed regs");
2537     llvm::Type *TyLo = ST->getElementType(0);
2538     llvm::Type *TyHi = ST->getElementType(1);
2539     assert((TyLo->isFPOrFPVectorTy() ^ TyHi->isFPOrFPVectorTy()) &&
2540            "Unexpected ABI info for mixed regs");
2541     llvm::Type *PTyLo = llvm::PointerType::getUnqual(TyLo);
2542     llvm::Type *PTyHi = llvm::PointerType::getUnqual(TyHi);
2543     llvm::Value *GPAddr = CGF.Builder.CreateGEP(RegAddr, gp_offset);
2544     llvm::Value *FPAddr = CGF.Builder.CreateGEP(RegAddr, fp_offset);
2545     llvm::Value *RegLoAddr = TyLo->isFloatingPointTy() ? FPAddr : GPAddr;
2546     llvm::Value *RegHiAddr = TyLo->isFloatingPointTy() ? GPAddr : FPAddr;
2547     llvm::Value *V =
2548       CGF.Builder.CreateLoad(CGF.Builder.CreateBitCast(RegLoAddr, PTyLo));
2549     CGF.Builder.CreateStore(V, CGF.Builder.CreateStructGEP(Tmp, 0));
2550     V = CGF.Builder.CreateLoad(CGF.Builder.CreateBitCast(RegHiAddr, PTyHi));
2551     CGF.Builder.CreateStore(V, CGF.Builder.CreateStructGEP(Tmp, 1));
2552 
2553     RegAddr = CGF.Builder.CreateBitCast(Tmp,
2554                                         llvm::PointerType::getUnqual(LTy));
2555   } else if (neededInt) {
2556     RegAddr = CGF.Builder.CreateGEP(RegAddr, gp_offset);
2557     RegAddr = CGF.Builder.CreateBitCast(RegAddr,
2558                                         llvm::PointerType::getUnqual(LTy));
2559 
2560     // Copy to a temporary if necessary to ensure the appropriate alignment.
2561     std::pair<CharUnits, CharUnits> SizeAlign =
2562         CGF.getContext().getTypeInfoInChars(Ty);
2563     uint64_t TySize = SizeAlign.first.getQuantity();
2564     unsigned TyAlign = SizeAlign.second.getQuantity();
2565     if (TyAlign > 8) {
2566       llvm::Value *Tmp = CGF.CreateMemTemp(Ty);
2567       CGF.Builder.CreateMemCpy(Tmp, RegAddr, TySize, 8, false);
2568       RegAddr = Tmp;
2569     }
2570   } else if (neededSSE == 1) {
2571     RegAddr = CGF.Builder.CreateGEP(RegAddr, fp_offset);
2572     RegAddr = CGF.Builder.CreateBitCast(RegAddr,
2573                                         llvm::PointerType::getUnqual(LTy));
2574   } else {
2575     assert(neededSSE == 2 && "Invalid number of needed registers!");
2576     // SSE registers are spaced 16 bytes apart in the register save
2577     // area, we need to collect the two eightbytes together.
2578     llvm::Value *RegAddrLo = CGF.Builder.CreateGEP(RegAddr, fp_offset);
2579     llvm::Value *RegAddrHi = CGF.Builder.CreateConstGEP1_32(RegAddrLo, 16);
2580     llvm::Type *DoubleTy = CGF.DoubleTy;
2581     llvm::Type *DblPtrTy =
2582       llvm::PointerType::getUnqual(DoubleTy);
2583     llvm::StructType *ST = llvm::StructType::get(DoubleTy, DoubleTy, NULL);
2584     llvm::Value *V, *Tmp = CGF.CreateMemTemp(Ty);
2585     Tmp = CGF.Builder.CreateBitCast(Tmp, ST->getPointerTo());
2586     V = CGF.Builder.CreateLoad(CGF.Builder.CreateBitCast(RegAddrLo,
2587                                                          DblPtrTy));
2588     CGF.Builder.CreateStore(V, CGF.Builder.CreateStructGEP(Tmp, 0));
2589     V = CGF.Builder.CreateLoad(CGF.Builder.CreateBitCast(RegAddrHi,
2590                                                          DblPtrTy));
2591     CGF.Builder.CreateStore(V, CGF.Builder.CreateStructGEP(Tmp, 1));
2592     RegAddr = CGF.Builder.CreateBitCast(Tmp,
2593                                         llvm::PointerType::getUnqual(LTy));
2594   }
2595 
2596   // AMD64-ABI 3.5.7p5: Step 5. Set:
2597   // l->gp_offset = l->gp_offset + num_gp * 8
2598   // l->fp_offset = l->fp_offset + num_fp * 16.
2599   if (neededInt) {
2600     llvm::Value *Offset = llvm::ConstantInt::get(CGF.Int32Ty, neededInt * 8);
2601     CGF.Builder.CreateStore(CGF.Builder.CreateAdd(gp_offset, Offset),
2602                             gp_offset_p);
2603   }
2604   if (neededSSE) {
2605     llvm::Value *Offset = llvm::ConstantInt::get(CGF.Int32Ty, neededSSE * 16);
2606     CGF.Builder.CreateStore(CGF.Builder.CreateAdd(fp_offset, Offset),
2607                             fp_offset_p);
2608   }
2609   CGF.EmitBranch(ContBlock);
2610 
2611   // Emit code to load the value if it was passed in memory.
2612 
2613   CGF.EmitBlock(InMemBlock);
2614   llvm::Value *MemAddr = EmitVAArgFromMemory(VAListAddr, Ty, CGF);
2615 
2616   // Return the appropriate result.
2617 
2618   CGF.EmitBlock(ContBlock);
2619   llvm::PHINode *ResAddr = CGF.Builder.CreatePHI(RegAddr->getType(), 2,
2620                                                  "vaarg.addr");
2621   ResAddr->addIncoming(RegAddr, InRegBlock);
2622   ResAddr->addIncoming(MemAddr, InMemBlock);
2623   return ResAddr;
2624 }
2625 
2626 ABIArgInfo WinX86_64ABIInfo::classify(QualType Ty, bool IsReturnType) const {
2627 
2628   if (Ty->isVoidType())
2629     return ABIArgInfo::getIgnore();
2630 
2631   if (const EnumType *EnumTy = Ty->getAs<EnumType>())
2632     Ty = EnumTy->getDecl()->getIntegerType();
2633 
2634   uint64_t Size = getContext().getTypeSize(Ty);
2635 
2636   if (const RecordType *RT = Ty->getAs<RecordType>()) {
2637     if (IsReturnType) {
2638       if (isRecordReturnIndirect(RT, getCXXABI()))
2639         return ABIArgInfo::getIndirect(0, false);
2640     } else {
2641       if (CGCXXABI::RecordArgABI RAA = getRecordArgABI(RT, getCXXABI()))
2642         return ABIArgInfo::getIndirect(0, RAA == CGCXXABI::RAA_DirectInMemory);
2643     }
2644 
2645     if (RT->getDecl()->hasFlexibleArrayMember())
2646       return ABIArgInfo::getIndirect(0, /*ByVal=*/false);
2647 
2648     // FIXME: mingw-w64-gcc emits 128-bit struct as i128
2649     if (Size == 128 && getTarget().getTriple().getOS() == llvm::Triple::MinGW32)
2650       return ABIArgInfo::getDirect(llvm::IntegerType::get(getVMContext(),
2651                                                           Size));
2652 
2653     // MS x64 ABI requirement: "Any argument that doesn't fit in 8 bytes, or is
2654     // not 1, 2, 4, or 8 bytes, must be passed by reference."
2655     if (Size <= 64 &&
2656         (Size & (Size - 1)) == 0)
2657       return ABIArgInfo::getDirect(llvm::IntegerType::get(getVMContext(),
2658                                                           Size));
2659 
2660     return ABIArgInfo::getIndirect(0, /*ByVal=*/false);
2661   }
2662 
2663   if (Ty->isPromotableIntegerType())
2664     return ABIArgInfo::getExtend();
2665 
2666   return ABIArgInfo::getDirect();
2667 }
2668 
2669 void WinX86_64ABIInfo::computeInfo(CGFunctionInfo &FI) const {
2670 
2671   QualType RetTy = FI.getReturnType();
2672   FI.getReturnInfo() = classify(RetTy, true);
2673 
2674   for (CGFunctionInfo::arg_iterator it = FI.arg_begin(), ie = FI.arg_end();
2675        it != ie; ++it)
2676     it->info = classify(it->type, false);
2677 }
2678 
2679 llvm::Value *WinX86_64ABIInfo::EmitVAArg(llvm::Value *VAListAddr, QualType Ty,
2680                                       CodeGenFunction &CGF) const {
2681   llvm::Type *BPP = CGF.Int8PtrPtrTy;
2682 
2683   CGBuilderTy &Builder = CGF.Builder;
2684   llvm::Value *VAListAddrAsBPP = Builder.CreateBitCast(VAListAddr, BPP,
2685                                                        "ap");
2686   llvm::Value *Addr = Builder.CreateLoad(VAListAddrAsBPP, "ap.cur");
2687   llvm::Type *PTy =
2688     llvm::PointerType::getUnqual(CGF.ConvertType(Ty));
2689   llvm::Value *AddrTyped = Builder.CreateBitCast(Addr, PTy);
2690 
2691   uint64_t Offset =
2692     llvm::RoundUpToAlignment(CGF.getContext().getTypeSize(Ty) / 8, 8);
2693   llvm::Value *NextAddr =
2694     Builder.CreateGEP(Addr, llvm::ConstantInt::get(CGF.Int32Ty, Offset),
2695                       "ap.next");
2696   Builder.CreateStore(NextAddr, VAListAddrAsBPP);
2697 
2698   return AddrTyped;
2699 }
2700 
2701 namespace {
2702 
2703 class NaClX86_64ABIInfo : public ABIInfo {
2704  public:
2705   NaClX86_64ABIInfo(CodeGen::CodeGenTypes &CGT, bool HasAVX)
2706       : ABIInfo(CGT), PInfo(CGT), NInfo(CGT, HasAVX) {}
2707   virtual void computeInfo(CGFunctionInfo &FI) const;
2708   virtual llvm::Value *EmitVAArg(llvm::Value *VAListAddr, QualType Ty,
2709                                  CodeGenFunction &CGF) const;
2710  private:
2711   PNaClABIInfo PInfo;  // Used for generating calls with pnaclcall callingconv.
2712   X86_64ABIInfo NInfo; // Used for everything else.
2713 };
2714 
2715 class NaClX86_64TargetCodeGenInfo : public TargetCodeGenInfo  {
2716  public:
2717   NaClX86_64TargetCodeGenInfo(CodeGen::CodeGenTypes &CGT, bool HasAVX)
2718       : TargetCodeGenInfo(new NaClX86_64ABIInfo(CGT, HasAVX)) {}
2719 };
2720 
2721 }
2722 
2723 void NaClX86_64ABIInfo::computeInfo(CGFunctionInfo &FI) const {
2724   if (FI.getASTCallingConvention() == CC_PnaclCall)
2725     PInfo.computeInfo(FI);
2726   else
2727     NInfo.computeInfo(FI);
2728 }
2729 
2730 llvm::Value *NaClX86_64ABIInfo::EmitVAArg(llvm::Value *VAListAddr, QualType Ty,
2731                                           CodeGenFunction &CGF) const {
2732   // Always use the native convention; calling pnacl-style varargs functions
2733   // is unuspported.
2734   return NInfo.EmitVAArg(VAListAddr, Ty, CGF);
2735 }
2736 
2737 
2738 // PowerPC-32
2739 
2740 namespace {
2741 class PPC32TargetCodeGenInfo : public DefaultTargetCodeGenInfo {
2742 public:
2743   PPC32TargetCodeGenInfo(CodeGenTypes &CGT) : DefaultTargetCodeGenInfo(CGT) {}
2744 
2745   int getDwarfEHStackPointer(CodeGen::CodeGenModule &M) const {
2746     // This is recovered from gcc output.
2747     return 1; // r1 is the dedicated stack pointer
2748   }
2749 
2750   bool initDwarfEHRegSizeTable(CodeGen::CodeGenFunction &CGF,
2751                                llvm::Value *Address) const;
2752 };
2753 
2754 }
2755 
2756 bool
2757 PPC32TargetCodeGenInfo::initDwarfEHRegSizeTable(CodeGen::CodeGenFunction &CGF,
2758                                                 llvm::Value *Address) const {
2759   // This is calculated from the LLVM and GCC tables and verified
2760   // against gcc output.  AFAIK all ABIs use the same encoding.
2761 
2762   CodeGen::CGBuilderTy &Builder = CGF.Builder;
2763 
2764   llvm::IntegerType *i8 = CGF.Int8Ty;
2765   llvm::Value *Four8 = llvm::ConstantInt::get(i8, 4);
2766   llvm::Value *Eight8 = llvm::ConstantInt::get(i8, 8);
2767   llvm::Value *Sixteen8 = llvm::ConstantInt::get(i8, 16);
2768 
2769   // 0-31: r0-31, the 4-byte general-purpose registers
2770   AssignToArrayRange(Builder, Address, Four8, 0, 31);
2771 
2772   // 32-63: fp0-31, the 8-byte floating-point registers
2773   AssignToArrayRange(Builder, Address, Eight8, 32, 63);
2774 
2775   // 64-76 are various 4-byte special-purpose registers:
2776   // 64: mq
2777   // 65: lr
2778   // 66: ctr
2779   // 67: ap
2780   // 68-75 cr0-7
2781   // 76: xer
2782   AssignToArrayRange(Builder, Address, Four8, 64, 76);
2783 
2784   // 77-108: v0-31, the 16-byte vector registers
2785   AssignToArrayRange(Builder, Address, Sixteen8, 77, 108);
2786 
2787   // 109: vrsave
2788   // 110: vscr
2789   // 111: spe_acc
2790   // 112: spefscr
2791   // 113: sfp
2792   AssignToArrayRange(Builder, Address, Four8, 109, 113);
2793 
2794   return false;
2795 }
2796 
2797 // PowerPC-64
2798 
2799 namespace {
2800 /// PPC64_SVR4_ABIInfo - The 64-bit PowerPC ELF (SVR4) ABI information.
2801 class PPC64_SVR4_ABIInfo : public DefaultABIInfo {
2802 
2803 public:
2804   PPC64_SVR4_ABIInfo(CodeGen::CodeGenTypes &CGT) : DefaultABIInfo(CGT) {}
2805 
2806   bool isPromotableTypeForABI(QualType Ty) const;
2807 
2808   ABIArgInfo classifyReturnType(QualType RetTy) const;
2809   ABIArgInfo classifyArgumentType(QualType Ty) const;
2810 
2811   // TODO: We can add more logic to computeInfo to improve performance.
2812   // Example: For aggregate arguments that fit in a register, we could
2813   // use getDirectInReg (as is done below for structs containing a single
2814   // floating-point value) to avoid pushing them to memory on function
2815   // entry.  This would require changing the logic in PPCISelLowering
2816   // when lowering the parameters in the caller and args in the callee.
2817   virtual void computeInfo(CGFunctionInfo &FI) const {
2818     FI.getReturnInfo() = classifyReturnType(FI.getReturnType());
2819     for (CGFunctionInfo::arg_iterator it = FI.arg_begin(), ie = FI.arg_end();
2820          it != ie; ++it) {
2821       // We rely on the default argument classification for the most part.
2822       // One exception:  An aggregate containing a single floating-point
2823       // or vector item must be passed in a register if one is available.
2824       const Type *T = isSingleElementStruct(it->type, getContext());
2825       if (T) {
2826         const BuiltinType *BT = T->getAs<BuiltinType>();
2827         if (T->isVectorType() || (BT && BT->isFloatingPoint())) {
2828           QualType QT(T, 0);
2829           it->info = ABIArgInfo::getDirectInReg(CGT.ConvertType(QT));
2830           continue;
2831         }
2832       }
2833       it->info = classifyArgumentType(it->type);
2834     }
2835   }
2836 
2837   virtual llvm::Value *EmitVAArg(llvm::Value *VAListAddr,
2838                                  QualType Ty,
2839                                  CodeGenFunction &CGF) const;
2840 };
2841 
2842 class PPC64_SVR4_TargetCodeGenInfo : public TargetCodeGenInfo {
2843 public:
2844   PPC64_SVR4_TargetCodeGenInfo(CodeGenTypes &CGT)
2845     : TargetCodeGenInfo(new PPC64_SVR4_ABIInfo(CGT)) {}
2846 
2847   int getDwarfEHStackPointer(CodeGen::CodeGenModule &M) const {
2848     // This is recovered from gcc output.
2849     return 1; // r1 is the dedicated stack pointer
2850   }
2851 
2852   bool initDwarfEHRegSizeTable(CodeGen::CodeGenFunction &CGF,
2853                                llvm::Value *Address) const;
2854 };
2855 
2856 class PPC64TargetCodeGenInfo : public DefaultTargetCodeGenInfo {
2857 public:
2858   PPC64TargetCodeGenInfo(CodeGenTypes &CGT) : DefaultTargetCodeGenInfo(CGT) {}
2859 
2860   int getDwarfEHStackPointer(CodeGen::CodeGenModule &M) const {
2861     // This is recovered from gcc output.
2862     return 1; // r1 is the dedicated stack pointer
2863   }
2864 
2865   bool initDwarfEHRegSizeTable(CodeGen::CodeGenFunction &CGF,
2866                                llvm::Value *Address) const;
2867 };
2868 
2869 }
2870 
2871 // Return true if the ABI requires Ty to be passed sign- or zero-
2872 // extended to 64 bits.
2873 bool
2874 PPC64_SVR4_ABIInfo::isPromotableTypeForABI(QualType Ty) const {
2875   // Treat an enum type as its underlying type.
2876   if (const EnumType *EnumTy = Ty->getAs<EnumType>())
2877     Ty = EnumTy->getDecl()->getIntegerType();
2878 
2879   // Promotable integer types are required to be promoted by the ABI.
2880   if (Ty->isPromotableIntegerType())
2881     return true;
2882 
2883   // In addition to the usual promotable integer types, we also need to
2884   // extend all 32-bit types, since the ABI requires promotion to 64 bits.
2885   if (const BuiltinType *BT = Ty->getAs<BuiltinType>())
2886     switch (BT->getKind()) {
2887     case BuiltinType::Int:
2888     case BuiltinType::UInt:
2889       return true;
2890     default:
2891       break;
2892     }
2893 
2894   return false;
2895 }
2896 
2897 ABIArgInfo
2898 PPC64_SVR4_ABIInfo::classifyArgumentType(QualType Ty) const {
2899   if (Ty->isAnyComplexType())
2900     return ABIArgInfo::getDirect();
2901 
2902   if (isAggregateTypeForABI(Ty)) {
2903     if (CGCXXABI::RecordArgABI RAA = getRecordArgABI(Ty, getCXXABI()))
2904       return ABIArgInfo::getIndirect(0, RAA == CGCXXABI::RAA_DirectInMemory);
2905 
2906     return ABIArgInfo::getIndirect(0);
2907   }
2908 
2909   return (isPromotableTypeForABI(Ty) ?
2910           ABIArgInfo::getExtend() : ABIArgInfo::getDirect());
2911 }
2912 
2913 ABIArgInfo
2914 PPC64_SVR4_ABIInfo::classifyReturnType(QualType RetTy) const {
2915   if (RetTy->isVoidType())
2916     return ABIArgInfo::getIgnore();
2917 
2918   if (RetTy->isAnyComplexType())
2919     return ABIArgInfo::getDirect();
2920 
2921   if (isAggregateTypeForABI(RetTy))
2922     return ABIArgInfo::getIndirect(0);
2923 
2924   return (isPromotableTypeForABI(RetTy) ?
2925           ABIArgInfo::getExtend() : ABIArgInfo::getDirect());
2926 }
2927 
2928 // Based on ARMABIInfo::EmitVAArg, adjusted for 64-bit machine.
2929 llvm::Value *PPC64_SVR4_ABIInfo::EmitVAArg(llvm::Value *VAListAddr,
2930                                            QualType Ty,
2931                                            CodeGenFunction &CGF) const {
2932   llvm::Type *BP = CGF.Int8PtrTy;
2933   llvm::Type *BPP = CGF.Int8PtrPtrTy;
2934 
2935   CGBuilderTy &Builder = CGF.Builder;
2936   llvm::Value *VAListAddrAsBPP = Builder.CreateBitCast(VAListAddr, BPP, "ap");
2937   llvm::Value *Addr = Builder.CreateLoad(VAListAddrAsBPP, "ap.cur");
2938 
2939   // Update the va_list pointer.  The pointer should be bumped by the
2940   // size of the object.  We can trust getTypeSize() except for a complex
2941   // type whose base type is smaller than a doubleword.  For these, the
2942   // size of the object is 16 bytes; see below for further explanation.
2943   unsigned SizeInBytes = CGF.getContext().getTypeSize(Ty) / 8;
2944   QualType BaseTy;
2945   unsigned CplxBaseSize = 0;
2946 
2947   if (const ComplexType *CTy = Ty->getAs<ComplexType>()) {
2948     BaseTy = CTy->getElementType();
2949     CplxBaseSize = CGF.getContext().getTypeSize(BaseTy) / 8;
2950     if (CplxBaseSize < 8)
2951       SizeInBytes = 16;
2952   }
2953 
2954   unsigned Offset = llvm::RoundUpToAlignment(SizeInBytes, 8);
2955   llvm::Value *NextAddr =
2956     Builder.CreateGEP(Addr, llvm::ConstantInt::get(CGF.Int64Ty, Offset),
2957                       "ap.next");
2958   Builder.CreateStore(NextAddr, VAListAddrAsBPP);
2959 
2960   // If we have a complex type and the base type is smaller than 8 bytes,
2961   // the ABI calls for the real and imaginary parts to be right-adjusted
2962   // in separate doublewords.  However, Clang expects us to produce a
2963   // pointer to a structure with the two parts packed tightly.  So generate
2964   // loads of the real and imaginary parts relative to the va_list pointer,
2965   // and store them to a temporary structure.
2966   if (CplxBaseSize && CplxBaseSize < 8) {
2967     llvm::Value *RealAddr = Builder.CreatePtrToInt(Addr, CGF.Int64Ty);
2968     llvm::Value *ImagAddr = RealAddr;
2969     RealAddr = Builder.CreateAdd(RealAddr, Builder.getInt64(8 - CplxBaseSize));
2970     ImagAddr = Builder.CreateAdd(ImagAddr, Builder.getInt64(16 - CplxBaseSize));
2971     llvm::Type *PBaseTy = llvm::PointerType::getUnqual(CGF.ConvertType(BaseTy));
2972     RealAddr = Builder.CreateIntToPtr(RealAddr, PBaseTy);
2973     ImagAddr = Builder.CreateIntToPtr(ImagAddr, PBaseTy);
2974     llvm::Value *Real = Builder.CreateLoad(RealAddr, false, ".vareal");
2975     llvm::Value *Imag = Builder.CreateLoad(ImagAddr, false, ".vaimag");
2976     llvm::Value *Ptr = CGF.CreateTempAlloca(CGT.ConvertTypeForMem(Ty),
2977                                             "vacplx");
2978     llvm::Value *RealPtr = Builder.CreateStructGEP(Ptr, 0, ".real");
2979     llvm::Value *ImagPtr = Builder.CreateStructGEP(Ptr, 1, ".imag");
2980     Builder.CreateStore(Real, RealPtr, false);
2981     Builder.CreateStore(Imag, ImagPtr, false);
2982     return Ptr;
2983   }
2984 
2985   // If the argument is smaller than 8 bytes, it is right-adjusted in
2986   // its doubleword slot.  Adjust the pointer to pick it up from the
2987   // correct offset.
2988   if (SizeInBytes < 8) {
2989     llvm::Value *AddrAsInt = Builder.CreatePtrToInt(Addr, CGF.Int64Ty);
2990     AddrAsInt = Builder.CreateAdd(AddrAsInt, Builder.getInt64(8 - SizeInBytes));
2991     Addr = Builder.CreateIntToPtr(AddrAsInt, BP);
2992   }
2993 
2994   llvm::Type *PTy = llvm::PointerType::getUnqual(CGF.ConvertType(Ty));
2995   return Builder.CreateBitCast(Addr, PTy);
2996 }
2997 
2998 static bool
2999 PPC64_initDwarfEHRegSizeTable(CodeGen::CodeGenFunction &CGF,
3000                               llvm::Value *Address) {
3001   // This is calculated from the LLVM and GCC tables and verified
3002   // against gcc output.  AFAIK all ABIs use the same encoding.
3003 
3004   CodeGen::CGBuilderTy &Builder = CGF.Builder;
3005 
3006   llvm::IntegerType *i8 = CGF.Int8Ty;
3007   llvm::Value *Four8 = llvm::ConstantInt::get(i8, 4);
3008   llvm::Value *Eight8 = llvm::ConstantInt::get(i8, 8);
3009   llvm::Value *Sixteen8 = llvm::ConstantInt::get(i8, 16);
3010 
3011   // 0-31: r0-31, the 8-byte general-purpose registers
3012   AssignToArrayRange(Builder, Address, Eight8, 0, 31);
3013 
3014   // 32-63: fp0-31, the 8-byte floating-point registers
3015   AssignToArrayRange(Builder, Address, Eight8, 32, 63);
3016 
3017   // 64-76 are various 4-byte special-purpose registers:
3018   // 64: mq
3019   // 65: lr
3020   // 66: ctr
3021   // 67: ap
3022   // 68-75 cr0-7
3023   // 76: xer
3024   AssignToArrayRange(Builder, Address, Four8, 64, 76);
3025 
3026   // 77-108: v0-31, the 16-byte vector registers
3027   AssignToArrayRange(Builder, Address, Sixteen8, 77, 108);
3028 
3029   // 109: vrsave
3030   // 110: vscr
3031   // 111: spe_acc
3032   // 112: spefscr
3033   // 113: sfp
3034   AssignToArrayRange(Builder, Address, Four8, 109, 113);
3035 
3036   return false;
3037 }
3038 
3039 bool
3040 PPC64_SVR4_TargetCodeGenInfo::initDwarfEHRegSizeTable(
3041   CodeGen::CodeGenFunction &CGF,
3042   llvm::Value *Address) const {
3043 
3044   return PPC64_initDwarfEHRegSizeTable(CGF, Address);
3045 }
3046 
3047 bool
3048 PPC64TargetCodeGenInfo::initDwarfEHRegSizeTable(CodeGen::CodeGenFunction &CGF,
3049                                                 llvm::Value *Address) const {
3050 
3051   return PPC64_initDwarfEHRegSizeTable(CGF, Address);
3052 }
3053 
3054 //===----------------------------------------------------------------------===//
3055 // ARM ABI Implementation
3056 //===----------------------------------------------------------------------===//
3057 
3058 namespace {
3059 
3060 class ARMABIInfo : public ABIInfo {
3061 public:
3062   enum ABIKind {
3063     APCS = 0,
3064     AAPCS = 1,
3065     AAPCS_VFP
3066   };
3067 
3068 private:
3069   ABIKind Kind;
3070 
3071 public:
3072   ARMABIInfo(CodeGenTypes &CGT, ABIKind _Kind) : ABIInfo(CGT), Kind(_Kind) {
3073     setRuntimeCC();
3074   }
3075 
3076   bool isEABI() const {
3077     switch (getTarget().getTriple().getEnvironment()) {
3078     case llvm::Triple::Android:
3079     case llvm::Triple::EABI:
3080     case llvm::Triple::EABIHF:
3081     case llvm::Triple::GNUEABI:
3082     case llvm::Triple::GNUEABIHF:
3083       return true;
3084     default:
3085       return false;
3086     }
3087   }
3088 
3089   bool isEABIHF() const {
3090     switch (getTarget().getTriple().getEnvironment()) {
3091     case llvm::Triple::EABIHF:
3092     case llvm::Triple::GNUEABIHF:
3093       return true;
3094     default:
3095       return false;
3096     }
3097   }
3098 
3099   ABIKind getABIKind() const { return Kind; }
3100 
3101 private:
3102   ABIArgInfo classifyReturnType(QualType RetTy, bool isVariadic) const;
3103   ABIArgInfo classifyArgumentType(QualType RetTy, int *VFPRegs,
3104                                   unsigned &AllocatedVFP,
3105                                   bool &IsHA, bool isVariadic) const;
3106   bool isIllegalVectorType(QualType Ty) const;
3107 
3108   virtual void computeInfo(CGFunctionInfo &FI) const;
3109 
3110   virtual llvm::Value *EmitVAArg(llvm::Value *VAListAddr, QualType Ty,
3111                                  CodeGenFunction &CGF) const;
3112 
3113   llvm::CallingConv::ID getLLVMDefaultCC() const;
3114   llvm::CallingConv::ID getABIDefaultCC() const;
3115   void setRuntimeCC();
3116 };
3117 
3118 class ARMTargetCodeGenInfo : public TargetCodeGenInfo {
3119 public:
3120   ARMTargetCodeGenInfo(CodeGenTypes &CGT, ARMABIInfo::ABIKind K)
3121     :TargetCodeGenInfo(new ARMABIInfo(CGT, K)) {}
3122 
3123   const ARMABIInfo &getABIInfo() const {
3124     return static_cast<const ARMABIInfo&>(TargetCodeGenInfo::getABIInfo());
3125   }
3126 
3127   int getDwarfEHStackPointer(CodeGen::CodeGenModule &M) const {
3128     return 13;
3129   }
3130 
3131   StringRef getARCRetainAutoreleasedReturnValueMarker() const {
3132     return "mov\tr7, r7\t\t@ marker for objc_retainAutoreleaseReturnValue";
3133   }
3134 
3135   bool initDwarfEHRegSizeTable(CodeGen::CodeGenFunction &CGF,
3136                                llvm::Value *Address) const {
3137     llvm::Value *Four8 = llvm::ConstantInt::get(CGF.Int8Ty, 4);
3138 
3139     // 0-15 are the 16 integer registers.
3140     AssignToArrayRange(CGF.Builder, Address, Four8, 0, 15);
3141     return false;
3142   }
3143 
3144   unsigned getSizeOfUnwindException() const {
3145     if (getABIInfo().isEABI()) return 88;
3146     return TargetCodeGenInfo::getSizeOfUnwindException();
3147   }
3148 
3149   void SetTargetAttributes(const Decl *D, llvm::GlobalValue *GV,
3150                            CodeGen::CodeGenModule &CGM) const {
3151     const FunctionDecl *FD = dyn_cast<FunctionDecl>(D);
3152     if (!FD)
3153       return;
3154 
3155     const ARMInterruptAttr *Attr = FD->getAttr<ARMInterruptAttr>();
3156     if (!Attr)
3157       return;
3158 
3159     const char *Kind;
3160     switch (Attr->getInterrupt()) {
3161     case ARMInterruptAttr::Generic: Kind = ""; break;
3162     case ARMInterruptAttr::IRQ:     Kind = "IRQ"; break;
3163     case ARMInterruptAttr::FIQ:     Kind = "FIQ"; break;
3164     case ARMInterruptAttr::SWI:     Kind = "SWI"; break;
3165     case ARMInterruptAttr::ABORT:   Kind = "ABORT"; break;
3166     case ARMInterruptAttr::UNDEF:   Kind = "UNDEF"; break;
3167     }
3168 
3169     llvm::Function *Fn = cast<llvm::Function>(GV);
3170 
3171     Fn->addFnAttr("interrupt", Kind);
3172 
3173     if (cast<ARMABIInfo>(getABIInfo()).getABIKind() == ARMABIInfo::APCS)
3174       return;
3175 
3176     // AAPCS guarantees that sp will be 8-byte aligned on any public interface,
3177     // however this is not necessarily true on taking any interrupt. Instruct
3178     // the backend to perform a realignment as part of the function prologue.
3179     llvm::AttrBuilder B;
3180     B.addStackAlignmentAttr(8);
3181     Fn->addAttributes(llvm::AttributeSet::FunctionIndex,
3182                       llvm::AttributeSet::get(CGM.getLLVMContext(),
3183                                               llvm::AttributeSet::FunctionIndex,
3184                                               B));
3185   }
3186 
3187 };
3188 
3189 }
3190 
3191 void ARMABIInfo::computeInfo(CGFunctionInfo &FI) const {
3192   // To correctly handle Homogeneous Aggregate, we need to keep track of the
3193   // VFP registers allocated so far.
3194   // C.1.vfp If the argument is a VFP CPRC and there are sufficient consecutive
3195   // VFP registers of the appropriate type unallocated then the argument is
3196   // allocated to the lowest-numbered sequence of such registers.
3197   // C.2.vfp If the argument is a VFP CPRC then any VFP registers that are
3198   // unallocated are marked as unavailable.
3199   unsigned AllocatedVFP = 0;
3200   int VFPRegs[16] = { 0 };
3201   FI.getReturnInfo() = classifyReturnType(FI.getReturnType(), FI.isVariadic());
3202   for (CGFunctionInfo::arg_iterator it = FI.arg_begin(), ie = FI.arg_end();
3203        it != ie; ++it) {
3204     unsigned PreAllocation = AllocatedVFP;
3205     bool IsHA = false;
3206     // 6.1.2.3 There is one VFP co-processor register class using registers
3207     // s0-s15 (d0-d7) for passing arguments.
3208     const unsigned NumVFPs = 16;
3209     it->info = classifyArgumentType(it->type, VFPRegs, AllocatedVFP, IsHA, FI.isVariadic());
3210     // If we do not have enough VFP registers for the HA, any VFP registers
3211     // that are unallocated are marked as unavailable. To achieve this, we add
3212     // padding of (NumVFPs - PreAllocation) floats.
3213     // Note that IsHA will only be set when using the AAPCS-VFP calling convention,
3214     // and the callee is not variadic.
3215     if (IsHA && AllocatedVFP > NumVFPs && PreAllocation < NumVFPs) {
3216       llvm::Type *PaddingTy = llvm::ArrayType::get(
3217           llvm::Type::getFloatTy(getVMContext()), NumVFPs - PreAllocation);
3218       it->info = ABIArgInfo::getExpandWithPadding(false, PaddingTy);
3219     }
3220   }
3221 
3222   // Always honor user-specified calling convention.
3223   if (FI.getCallingConvention() != llvm::CallingConv::C)
3224     return;
3225 
3226   llvm::CallingConv::ID cc = getRuntimeCC();
3227   if (cc != llvm::CallingConv::C)
3228     FI.setEffectiveCallingConvention(cc);
3229 }
3230 
3231 /// Return the default calling convention that LLVM will use.
3232 llvm::CallingConv::ID ARMABIInfo::getLLVMDefaultCC() const {
3233   // The default calling convention that LLVM will infer.
3234   if (isEABIHF())
3235     return llvm::CallingConv::ARM_AAPCS_VFP;
3236   else if (isEABI())
3237     return llvm::CallingConv::ARM_AAPCS;
3238   else
3239     return llvm::CallingConv::ARM_APCS;
3240 }
3241 
3242 /// Return the calling convention that our ABI would like us to use
3243 /// as the C calling convention.
3244 llvm::CallingConv::ID ARMABIInfo::getABIDefaultCC() const {
3245   switch (getABIKind()) {
3246   case APCS: return llvm::CallingConv::ARM_APCS;
3247   case AAPCS: return llvm::CallingConv::ARM_AAPCS;
3248   case AAPCS_VFP: return llvm::CallingConv::ARM_AAPCS_VFP;
3249   }
3250   llvm_unreachable("bad ABI kind");
3251 }
3252 
3253 void ARMABIInfo::setRuntimeCC() {
3254   assert(getRuntimeCC() == llvm::CallingConv::C);
3255 
3256   // Don't muddy up the IR with a ton of explicit annotations if
3257   // they'd just match what LLVM will infer from the triple.
3258   llvm::CallingConv::ID abiCC = getABIDefaultCC();
3259   if (abiCC != getLLVMDefaultCC())
3260     RuntimeCC = abiCC;
3261 }
3262 
3263 /// isHomogeneousAggregate - Return true if a type is an AAPCS-VFP homogeneous
3264 /// aggregate.  If HAMembers is non-null, the number of base elements
3265 /// contained in the type is returned through it; this is used for the
3266 /// recursive calls that check aggregate component types.
3267 static bool isHomogeneousAggregate(QualType Ty, const Type *&Base,
3268                                    ASTContext &Context,
3269                                    uint64_t *HAMembers = 0) {
3270   uint64_t Members = 0;
3271   if (const ConstantArrayType *AT = Context.getAsConstantArrayType(Ty)) {
3272     if (!isHomogeneousAggregate(AT->getElementType(), Base, Context, &Members))
3273       return false;
3274     Members *= AT->getSize().getZExtValue();
3275   } else if (const RecordType *RT = Ty->getAs<RecordType>()) {
3276     const RecordDecl *RD = RT->getDecl();
3277     if (RD->hasFlexibleArrayMember())
3278       return false;
3279 
3280     Members = 0;
3281     for (RecordDecl::field_iterator i = RD->field_begin(), e = RD->field_end();
3282          i != e; ++i) {
3283       const FieldDecl *FD = *i;
3284       uint64_t FldMembers;
3285       if (!isHomogeneousAggregate(FD->getType(), Base, Context, &FldMembers))
3286         return false;
3287 
3288       Members = (RD->isUnion() ?
3289                  std::max(Members, FldMembers) : Members + FldMembers);
3290     }
3291   } else {
3292     Members = 1;
3293     if (const ComplexType *CT = Ty->getAs<ComplexType>()) {
3294       Members = 2;
3295       Ty = CT->getElementType();
3296     }
3297 
3298     // Homogeneous aggregates for AAPCS-VFP must have base types of float,
3299     // double, or 64-bit or 128-bit vectors.
3300     if (const BuiltinType *BT = Ty->getAs<BuiltinType>()) {
3301       if (BT->getKind() != BuiltinType::Float &&
3302           BT->getKind() != BuiltinType::Double &&
3303           BT->getKind() != BuiltinType::LongDouble)
3304         return false;
3305     } else if (const VectorType *VT = Ty->getAs<VectorType>()) {
3306       unsigned VecSize = Context.getTypeSize(VT);
3307       if (VecSize != 64 && VecSize != 128)
3308         return false;
3309     } else {
3310       return false;
3311     }
3312 
3313     // The base type must be the same for all members.  Vector types of the
3314     // same total size are treated as being equivalent here.
3315     const Type *TyPtr = Ty.getTypePtr();
3316     if (!Base)
3317       Base = TyPtr;
3318     if (Base != TyPtr &&
3319         (!Base->isVectorType() || !TyPtr->isVectorType() ||
3320          Context.getTypeSize(Base) != Context.getTypeSize(TyPtr)))
3321       return false;
3322   }
3323 
3324   // Homogeneous Aggregates can have at most 4 members of the base type.
3325   if (HAMembers)
3326     *HAMembers = Members;
3327 
3328   return (Members > 0 && Members <= 4);
3329 }
3330 
3331 /// markAllocatedVFPs - update VFPRegs according to the alignment and
3332 /// number of VFP registers (unit is S register) requested.
3333 static void markAllocatedVFPs(int *VFPRegs, unsigned &AllocatedVFP,
3334                               unsigned Alignment,
3335                               unsigned NumRequired) {
3336   // Early Exit.
3337   if (AllocatedVFP >= 16)
3338     return;
3339   // C.1.vfp If the argument is a VFP CPRC and there are sufficient consecutive
3340   // VFP registers of the appropriate type unallocated then the argument is
3341   // allocated to the lowest-numbered sequence of such registers.
3342   for (unsigned I = 0; I < 16; I += Alignment) {
3343     bool FoundSlot = true;
3344     for (unsigned J = I, JEnd = I + NumRequired; J < JEnd; J++)
3345       if (J >= 16 || VFPRegs[J]) {
3346          FoundSlot = false;
3347          break;
3348       }
3349     if (FoundSlot) {
3350       for (unsigned J = I, JEnd = I + NumRequired; J < JEnd; J++)
3351         VFPRegs[J] = 1;
3352       AllocatedVFP += NumRequired;
3353       return;
3354     }
3355   }
3356   // C.2.vfp If the argument is a VFP CPRC then any VFP registers that are
3357   // unallocated are marked as unavailable.
3358   for (unsigned I = 0; I < 16; I++)
3359     VFPRegs[I] = 1;
3360   AllocatedVFP = 17; // We do not have enough VFP registers.
3361 }
3362 
3363 ABIArgInfo ARMABIInfo::classifyArgumentType(QualType Ty, int *VFPRegs,
3364                                             unsigned &AllocatedVFP,
3365                                             bool &IsHA, bool isVariadic) const {
3366   // We update number of allocated VFPs according to
3367   // 6.1.2.1 The following argument types are VFP CPRCs:
3368   //   A single-precision floating-point type (including promoted
3369   //   half-precision types); A double-precision floating-point type;
3370   //   A 64-bit or 128-bit containerized vector type; Homogeneous Aggregate
3371   //   with a Base Type of a single- or double-precision floating-point type,
3372   //   64-bit containerized vectors or 128-bit containerized vectors with one
3373   //   to four Elements.
3374 
3375   // Handle illegal vector types here.
3376   if (isIllegalVectorType(Ty)) {
3377     uint64_t Size = getContext().getTypeSize(Ty);
3378     if (Size <= 32) {
3379       llvm::Type *ResType =
3380           llvm::Type::getInt32Ty(getVMContext());
3381       return ABIArgInfo::getDirect(ResType);
3382     }
3383     if (Size == 64) {
3384       llvm::Type *ResType = llvm::VectorType::get(
3385           llvm::Type::getInt32Ty(getVMContext()), 2);
3386       markAllocatedVFPs(VFPRegs, AllocatedVFP, 2, 2);
3387       return ABIArgInfo::getDirect(ResType);
3388     }
3389     if (Size == 128) {
3390       llvm::Type *ResType = llvm::VectorType::get(
3391           llvm::Type::getInt32Ty(getVMContext()), 4);
3392       markAllocatedVFPs(VFPRegs, AllocatedVFP, 4, 4);
3393       return ABIArgInfo::getDirect(ResType);
3394     }
3395     return ABIArgInfo::getIndirect(0, /*ByVal=*/false);
3396   }
3397   // Update VFPRegs for legal vector types.
3398   if (const VectorType *VT = Ty->getAs<VectorType>()) {
3399     uint64_t Size = getContext().getTypeSize(VT);
3400     // Size of a legal vector should be power of 2 and above 64.
3401     markAllocatedVFPs(VFPRegs, AllocatedVFP, Size >= 128 ? 4 : 2, Size / 32);
3402   }
3403   // Update VFPRegs for floating point types.
3404   if (const BuiltinType *BT = Ty->getAs<BuiltinType>()) {
3405     if (BT->getKind() == BuiltinType::Half ||
3406         BT->getKind() == BuiltinType::Float)
3407       markAllocatedVFPs(VFPRegs, AllocatedVFP, 1, 1);
3408     if (BT->getKind() == BuiltinType::Double ||
3409         BT->getKind() == BuiltinType::LongDouble)
3410       markAllocatedVFPs(VFPRegs, AllocatedVFP, 2, 2);
3411   }
3412 
3413   if (!isAggregateTypeForABI(Ty)) {
3414     // Treat an enum type as its underlying type.
3415     if (const EnumType *EnumTy = Ty->getAs<EnumType>())
3416       Ty = EnumTy->getDecl()->getIntegerType();
3417 
3418     return (Ty->isPromotableIntegerType() ?
3419             ABIArgInfo::getExtend() : ABIArgInfo::getDirect());
3420   }
3421 
3422   if (CGCXXABI::RecordArgABI RAA = getRecordArgABI(Ty, getCXXABI()))
3423     return ABIArgInfo::getIndirect(0, RAA == CGCXXABI::RAA_DirectInMemory);
3424 
3425   // Ignore empty records.
3426   if (isEmptyRecord(getContext(), Ty, true))
3427     return ABIArgInfo::getIgnore();
3428 
3429   if (getABIKind() == ARMABIInfo::AAPCS_VFP && !isVariadic) {
3430     // Homogeneous Aggregates need to be expanded when we can fit the aggregate
3431     // into VFP registers.
3432     const Type *Base = 0;
3433     uint64_t Members = 0;
3434     if (isHomogeneousAggregate(Ty, Base, getContext(), &Members)) {
3435       assert(Base && "Base class should be set for homogeneous aggregate");
3436       // Base can be a floating-point or a vector.
3437       if (Base->isVectorType()) {
3438         // ElementSize is in number of floats.
3439         unsigned ElementSize = getContext().getTypeSize(Base) == 64 ? 2 : 4;
3440         markAllocatedVFPs(VFPRegs, AllocatedVFP, ElementSize,
3441                           Members * ElementSize);
3442       } else if (Base->isSpecificBuiltinType(BuiltinType::Float))
3443         markAllocatedVFPs(VFPRegs, AllocatedVFP, 1, Members);
3444       else {
3445         assert(Base->isSpecificBuiltinType(BuiltinType::Double) ||
3446                Base->isSpecificBuiltinType(BuiltinType::LongDouble));
3447         markAllocatedVFPs(VFPRegs, AllocatedVFP, 2, Members * 2);
3448       }
3449       IsHA = true;
3450       return ABIArgInfo::getExpand();
3451     }
3452   }
3453 
3454   // Support byval for ARM.
3455   // The ABI alignment for APCS is 4-byte and for AAPCS at least 4-byte and at
3456   // most 8-byte. We realign the indirect argument if type alignment is bigger
3457   // than ABI alignment.
3458   uint64_t ABIAlign = 4;
3459   uint64_t TyAlign = getContext().getTypeAlign(Ty) / 8;
3460   if (getABIKind() == ARMABIInfo::AAPCS_VFP ||
3461       getABIKind() == ARMABIInfo::AAPCS)
3462     ABIAlign = std::min(std::max(TyAlign, (uint64_t)4), (uint64_t)8);
3463   if (getContext().getTypeSizeInChars(Ty) > CharUnits::fromQuantity(64)) {
3464     return ABIArgInfo::getIndirect(0, /*ByVal=*/true,
3465            /*Realign=*/TyAlign > ABIAlign);
3466   }
3467 
3468   // Otherwise, pass by coercing to a structure of the appropriate size.
3469   llvm::Type* ElemTy;
3470   unsigned SizeRegs;
3471   // FIXME: Try to match the types of the arguments more accurately where
3472   // we can.
3473   if (getContext().getTypeAlign(Ty) <= 32) {
3474     ElemTy = llvm::Type::getInt32Ty(getVMContext());
3475     SizeRegs = (getContext().getTypeSize(Ty) + 31) / 32;
3476   } else {
3477     ElemTy = llvm::Type::getInt64Ty(getVMContext());
3478     SizeRegs = (getContext().getTypeSize(Ty) + 63) / 64;
3479   }
3480 
3481   llvm::Type *STy =
3482     llvm::StructType::get(llvm::ArrayType::get(ElemTy, SizeRegs), NULL);
3483   return ABIArgInfo::getDirect(STy);
3484 }
3485 
3486 static bool isIntegerLikeType(QualType Ty, ASTContext &Context,
3487                               llvm::LLVMContext &VMContext) {
3488   // APCS, C Language Calling Conventions, Non-Simple Return Values: A structure
3489   // is called integer-like if its size is less than or equal to one word, and
3490   // the offset of each of its addressable sub-fields is zero.
3491 
3492   uint64_t Size = Context.getTypeSize(Ty);
3493 
3494   // Check that the type fits in a word.
3495   if (Size > 32)
3496     return false;
3497 
3498   // FIXME: Handle vector types!
3499   if (Ty->isVectorType())
3500     return false;
3501 
3502   // Float types are never treated as "integer like".
3503   if (Ty->isRealFloatingType())
3504     return false;
3505 
3506   // If this is a builtin or pointer type then it is ok.
3507   if (Ty->getAs<BuiltinType>() || Ty->isPointerType())
3508     return true;
3509 
3510   // Small complex integer types are "integer like".
3511   if (const ComplexType *CT = Ty->getAs<ComplexType>())
3512     return isIntegerLikeType(CT->getElementType(), Context, VMContext);
3513 
3514   // Single element and zero sized arrays should be allowed, by the definition
3515   // above, but they are not.
3516 
3517   // Otherwise, it must be a record type.
3518   const RecordType *RT = Ty->getAs<RecordType>();
3519   if (!RT) return false;
3520 
3521   // Ignore records with flexible arrays.
3522   const RecordDecl *RD = RT->getDecl();
3523   if (RD->hasFlexibleArrayMember())
3524     return false;
3525 
3526   // Check that all sub-fields are at offset 0, and are themselves "integer
3527   // like".
3528   const ASTRecordLayout &Layout = Context.getASTRecordLayout(RD);
3529 
3530   bool HadField = false;
3531   unsigned idx = 0;
3532   for (RecordDecl::field_iterator i = RD->field_begin(), e = RD->field_end();
3533        i != e; ++i, ++idx) {
3534     const FieldDecl *FD = *i;
3535 
3536     // Bit-fields are not addressable, we only need to verify they are "integer
3537     // like". We still have to disallow a subsequent non-bitfield, for example:
3538     //   struct { int : 0; int x }
3539     // is non-integer like according to gcc.
3540     if (FD->isBitField()) {
3541       if (!RD->isUnion())
3542         HadField = true;
3543 
3544       if (!isIntegerLikeType(FD->getType(), Context, VMContext))
3545         return false;
3546 
3547       continue;
3548     }
3549 
3550     // Check if this field is at offset 0.
3551     if (Layout.getFieldOffset(idx) != 0)
3552       return false;
3553 
3554     if (!isIntegerLikeType(FD->getType(), Context, VMContext))
3555       return false;
3556 
3557     // Only allow at most one field in a structure. This doesn't match the
3558     // wording above, but follows gcc in situations with a field following an
3559     // empty structure.
3560     if (!RD->isUnion()) {
3561       if (HadField)
3562         return false;
3563 
3564       HadField = true;
3565     }
3566   }
3567 
3568   return true;
3569 }
3570 
3571 ABIArgInfo ARMABIInfo::classifyReturnType(QualType RetTy, bool isVariadic) const {
3572   if (RetTy->isVoidType())
3573     return ABIArgInfo::getIgnore();
3574 
3575   // Large vector types should be returned via memory.
3576   if (RetTy->isVectorType() && getContext().getTypeSize(RetTy) > 128)
3577     return ABIArgInfo::getIndirect(0);
3578 
3579   if (!isAggregateTypeForABI(RetTy)) {
3580     // Treat an enum type as its underlying type.
3581     if (const EnumType *EnumTy = RetTy->getAs<EnumType>())
3582       RetTy = EnumTy->getDecl()->getIntegerType();
3583 
3584     return (RetTy->isPromotableIntegerType() ?
3585             ABIArgInfo::getExtend() : ABIArgInfo::getDirect());
3586   }
3587 
3588   // Structures with either a non-trivial destructor or a non-trivial
3589   // copy constructor are always indirect.
3590   if (isRecordReturnIndirect(RetTy, getCXXABI()))
3591     return ABIArgInfo::getIndirect(0, /*ByVal=*/false);
3592 
3593   // Are we following APCS?
3594   if (getABIKind() == APCS) {
3595     if (isEmptyRecord(getContext(), RetTy, false))
3596       return ABIArgInfo::getIgnore();
3597 
3598     // Complex types are all returned as packed integers.
3599     //
3600     // FIXME: Consider using 2 x vector types if the back end handles them
3601     // correctly.
3602     if (RetTy->isAnyComplexType())
3603       return ABIArgInfo::getDirect(llvm::IntegerType::get(getVMContext(),
3604                                               getContext().getTypeSize(RetTy)));
3605 
3606     // Integer like structures are returned in r0.
3607     if (isIntegerLikeType(RetTy, getContext(), getVMContext())) {
3608       // Return in the smallest viable integer type.
3609       uint64_t Size = getContext().getTypeSize(RetTy);
3610       if (Size <= 8)
3611         return ABIArgInfo::getDirect(llvm::Type::getInt8Ty(getVMContext()));
3612       if (Size <= 16)
3613         return ABIArgInfo::getDirect(llvm::Type::getInt16Ty(getVMContext()));
3614       return ABIArgInfo::getDirect(llvm::Type::getInt32Ty(getVMContext()));
3615     }
3616 
3617     // Otherwise return in memory.
3618     return ABIArgInfo::getIndirect(0);
3619   }
3620 
3621   // Otherwise this is an AAPCS variant.
3622 
3623   if (isEmptyRecord(getContext(), RetTy, true))
3624     return ABIArgInfo::getIgnore();
3625 
3626   // Check for homogeneous aggregates with AAPCS-VFP.
3627   if (getABIKind() == AAPCS_VFP && !isVariadic) {
3628     const Type *Base = 0;
3629     if (isHomogeneousAggregate(RetTy, Base, getContext())) {
3630       assert(Base && "Base class should be set for homogeneous aggregate");
3631       // Homogeneous Aggregates are returned directly.
3632       return ABIArgInfo::getDirect();
3633     }
3634   }
3635 
3636   // Aggregates <= 4 bytes are returned in r0; other aggregates
3637   // are returned indirectly.
3638   uint64_t Size = getContext().getTypeSize(RetTy);
3639   if (Size <= 32) {
3640     // Return in the smallest viable integer type.
3641     if (Size <= 8)
3642       return ABIArgInfo::getDirect(llvm::Type::getInt8Ty(getVMContext()));
3643     if (Size <= 16)
3644       return ABIArgInfo::getDirect(llvm::Type::getInt16Ty(getVMContext()));
3645     return ABIArgInfo::getDirect(llvm::Type::getInt32Ty(getVMContext()));
3646   }
3647 
3648   return ABIArgInfo::getIndirect(0);
3649 }
3650 
3651 /// isIllegalVector - check whether Ty is an illegal vector type.
3652 bool ARMABIInfo::isIllegalVectorType(QualType Ty) const {
3653   if (const VectorType *VT = Ty->getAs<VectorType>()) {
3654     // Check whether VT is legal.
3655     unsigned NumElements = VT->getNumElements();
3656     uint64_t Size = getContext().getTypeSize(VT);
3657     // NumElements should be power of 2.
3658     if ((NumElements & (NumElements - 1)) != 0)
3659       return true;
3660     // Size should be greater than 32 bits.
3661     return Size <= 32;
3662   }
3663   return false;
3664 }
3665 
3666 llvm::Value *ARMABIInfo::EmitVAArg(llvm::Value *VAListAddr, QualType Ty,
3667                                    CodeGenFunction &CGF) const {
3668   llvm::Type *BP = CGF.Int8PtrTy;
3669   llvm::Type *BPP = CGF.Int8PtrPtrTy;
3670 
3671   CGBuilderTy &Builder = CGF.Builder;
3672   llvm::Value *VAListAddrAsBPP = Builder.CreateBitCast(VAListAddr, BPP, "ap");
3673   llvm::Value *Addr = Builder.CreateLoad(VAListAddrAsBPP, "ap.cur");
3674 
3675   if (isEmptyRecord(getContext(), Ty, true)) {
3676     // These are ignored for parameter passing purposes.
3677     llvm::Type *PTy = llvm::PointerType::getUnqual(CGF.ConvertType(Ty));
3678     return Builder.CreateBitCast(Addr, PTy);
3679   }
3680 
3681   uint64_t Size = CGF.getContext().getTypeSize(Ty) / 8;
3682   uint64_t TyAlign = CGF.getContext().getTypeAlign(Ty) / 8;
3683   bool IsIndirect = false;
3684 
3685   // The ABI alignment for 64-bit or 128-bit vectors is 8 for AAPCS and 4 for
3686   // APCS. For AAPCS, the ABI alignment is at least 4-byte and at most 8-byte.
3687   if (getABIKind() == ARMABIInfo::AAPCS_VFP ||
3688       getABIKind() == ARMABIInfo::AAPCS)
3689     TyAlign = std::min(std::max(TyAlign, (uint64_t)4), (uint64_t)8);
3690   else
3691     TyAlign = 4;
3692   // Use indirect if size of the illegal vector is bigger than 16 bytes.
3693   if (isIllegalVectorType(Ty) && Size > 16) {
3694     IsIndirect = true;
3695     Size = 4;
3696     TyAlign = 4;
3697   }
3698 
3699   // Handle address alignment for ABI alignment > 4 bytes.
3700   if (TyAlign > 4) {
3701     assert((TyAlign & (TyAlign - 1)) == 0 &&
3702            "Alignment is not power of 2!");
3703     llvm::Value *AddrAsInt = Builder.CreatePtrToInt(Addr, CGF.Int32Ty);
3704     AddrAsInt = Builder.CreateAdd(AddrAsInt, Builder.getInt32(TyAlign - 1));
3705     AddrAsInt = Builder.CreateAnd(AddrAsInt, Builder.getInt32(~(TyAlign - 1)));
3706     Addr = Builder.CreateIntToPtr(AddrAsInt, BP, "ap.align");
3707   }
3708 
3709   uint64_t Offset =
3710     llvm::RoundUpToAlignment(Size, 4);
3711   llvm::Value *NextAddr =
3712     Builder.CreateGEP(Addr, llvm::ConstantInt::get(CGF.Int32Ty, Offset),
3713                       "ap.next");
3714   Builder.CreateStore(NextAddr, VAListAddrAsBPP);
3715 
3716   if (IsIndirect)
3717     Addr = Builder.CreateLoad(Builder.CreateBitCast(Addr, BPP));
3718   else if (TyAlign < CGF.getContext().getTypeAlign(Ty) / 8) {
3719     // We can't directly cast ap.cur to pointer to a vector type, since ap.cur
3720     // may not be correctly aligned for the vector type. We create an aligned
3721     // temporary space and copy the content over from ap.cur to the temporary
3722     // space. This is necessary if the natural alignment of the type is greater
3723     // than the ABI alignment.
3724     llvm::Type *I8PtrTy = Builder.getInt8PtrTy();
3725     CharUnits CharSize = getContext().getTypeSizeInChars(Ty);
3726     llvm::Value *AlignedTemp = CGF.CreateTempAlloca(CGF.ConvertType(Ty),
3727                                                     "var.align");
3728     llvm::Value *Dst = Builder.CreateBitCast(AlignedTemp, I8PtrTy);
3729     llvm::Value *Src = Builder.CreateBitCast(Addr, I8PtrTy);
3730     Builder.CreateMemCpy(Dst, Src,
3731         llvm::ConstantInt::get(CGF.IntPtrTy, CharSize.getQuantity()),
3732         TyAlign, false);
3733     Addr = AlignedTemp; //The content is in aligned location.
3734   }
3735   llvm::Type *PTy =
3736     llvm::PointerType::getUnqual(CGF.ConvertType(Ty));
3737   llvm::Value *AddrTyped = Builder.CreateBitCast(Addr, PTy);
3738 
3739   return AddrTyped;
3740 }
3741 
3742 namespace {
3743 
3744 class NaClARMABIInfo : public ABIInfo {
3745  public:
3746   NaClARMABIInfo(CodeGen::CodeGenTypes &CGT, ARMABIInfo::ABIKind Kind)
3747       : ABIInfo(CGT), PInfo(CGT), NInfo(CGT, Kind) {}
3748   virtual void computeInfo(CGFunctionInfo &FI) const;
3749   virtual llvm::Value *EmitVAArg(llvm::Value *VAListAddr, QualType Ty,
3750                                  CodeGenFunction &CGF) const;
3751  private:
3752   PNaClABIInfo PInfo; // Used for generating calls with pnaclcall callingconv.
3753   ARMABIInfo NInfo; // Used for everything else.
3754 };
3755 
3756 class NaClARMTargetCodeGenInfo : public TargetCodeGenInfo  {
3757  public:
3758   NaClARMTargetCodeGenInfo(CodeGen::CodeGenTypes &CGT, ARMABIInfo::ABIKind Kind)
3759       : TargetCodeGenInfo(new NaClARMABIInfo(CGT, Kind)) {}
3760 };
3761 
3762 }
3763 
3764 void NaClARMABIInfo::computeInfo(CGFunctionInfo &FI) const {
3765   if (FI.getASTCallingConvention() == CC_PnaclCall)
3766     PInfo.computeInfo(FI);
3767   else
3768     static_cast<const ABIInfo&>(NInfo).computeInfo(FI);
3769 }
3770 
3771 llvm::Value *NaClARMABIInfo::EmitVAArg(llvm::Value *VAListAddr, QualType Ty,
3772                                        CodeGenFunction &CGF) const {
3773   // Always use the native convention; calling pnacl-style varargs functions
3774   // is unsupported.
3775   return static_cast<const ABIInfo&>(NInfo).EmitVAArg(VAListAddr, Ty, CGF);
3776 }
3777 
3778 //===----------------------------------------------------------------------===//
3779 // AArch64 ABI Implementation
3780 //===----------------------------------------------------------------------===//
3781 
3782 namespace {
3783 
3784 class AArch64ABIInfo : public ABIInfo {
3785 public:
3786   AArch64ABIInfo(CodeGenTypes &CGT) : ABIInfo(CGT) {}
3787 
3788 private:
3789   // The AArch64 PCS is explicit about return types and argument types being
3790   // handled identically, so we don't need to draw a distinction between
3791   // Argument and Return classification.
3792   ABIArgInfo classifyGenericType(QualType Ty, int &FreeIntRegs,
3793                                  int &FreeVFPRegs) const;
3794 
3795   ABIArgInfo tryUseRegs(QualType Ty, int &FreeRegs, int RegsNeeded, bool IsInt,
3796                         llvm::Type *DirectTy = 0) const;
3797 
3798   virtual void computeInfo(CGFunctionInfo &FI) const;
3799 
3800   virtual llvm::Value *EmitVAArg(llvm::Value *VAListAddr, QualType Ty,
3801                                  CodeGenFunction &CGF) const;
3802 };
3803 
3804 class AArch64TargetCodeGenInfo : public TargetCodeGenInfo {
3805 public:
3806   AArch64TargetCodeGenInfo(CodeGenTypes &CGT)
3807     :TargetCodeGenInfo(new AArch64ABIInfo(CGT)) {}
3808 
3809   const AArch64ABIInfo &getABIInfo() const {
3810     return static_cast<const AArch64ABIInfo&>(TargetCodeGenInfo::getABIInfo());
3811   }
3812 
3813   int getDwarfEHStackPointer(CodeGen::CodeGenModule &M) const {
3814     return 31;
3815   }
3816 
3817   bool initDwarfEHRegSizeTable(CodeGen::CodeGenFunction &CGF,
3818                                llvm::Value *Address) const {
3819     // 0-31 are x0-x30 and sp: 8 bytes each
3820     llvm::Value *Eight8 = llvm::ConstantInt::get(CGF.Int8Ty, 8);
3821     AssignToArrayRange(CGF.Builder, Address, Eight8, 0, 31);
3822 
3823     // 64-95 are v0-v31: 16 bytes each
3824     llvm::Value *Sixteen8 = llvm::ConstantInt::get(CGF.Int8Ty, 16);
3825     AssignToArrayRange(CGF.Builder, Address, Sixteen8, 64, 95);
3826 
3827     return false;
3828   }
3829 
3830 };
3831 
3832 }
3833 
3834 void AArch64ABIInfo::computeInfo(CGFunctionInfo &FI) const {
3835   int FreeIntRegs = 8, FreeVFPRegs = 8;
3836 
3837   FI.getReturnInfo() = classifyGenericType(FI.getReturnType(),
3838                                            FreeIntRegs, FreeVFPRegs);
3839 
3840   FreeIntRegs = FreeVFPRegs = 8;
3841   for (CGFunctionInfo::arg_iterator it = FI.arg_begin(), ie = FI.arg_end();
3842        it != ie; ++it) {
3843     it->info = classifyGenericType(it->type, FreeIntRegs, FreeVFPRegs);
3844 
3845   }
3846 }
3847 
3848 ABIArgInfo
3849 AArch64ABIInfo::tryUseRegs(QualType Ty, int &FreeRegs, int RegsNeeded,
3850                            bool IsInt, llvm::Type *DirectTy) const {
3851   if (FreeRegs >= RegsNeeded) {
3852     FreeRegs -= RegsNeeded;
3853     return ABIArgInfo::getDirect(DirectTy);
3854   }
3855 
3856   llvm::Type *Padding = 0;
3857 
3858   // We need padding so that later arguments don't get filled in anyway. That
3859   // wouldn't happen if only ByVal arguments followed in the same category, but
3860   // a large structure will simply seem to be a pointer as far as LLVM is
3861   // concerned.
3862   if (FreeRegs > 0) {
3863     if (IsInt)
3864       Padding = llvm::Type::getInt64Ty(getVMContext());
3865     else
3866       Padding = llvm::Type::getFloatTy(getVMContext());
3867 
3868     // Either [N x i64] or [N x float].
3869     Padding = llvm::ArrayType::get(Padding, FreeRegs);
3870     FreeRegs = 0;
3871   }
3872 
3873   return ABIArgInfo::getIndirect(getContext().getTypeAlign(Ty) / 8,
3874                                  /*IsByVal=*/ true, /*Realign=*/ false,
3875                                  Padding);
3876 }
3877 
3878 
3879 ABIArgInfo AArch64ABIInfo::classifyGenericType(QualType Ty,
3880                                                int &FreeIntRegs,
3881                                                int &FreeVFPRegs) const {
3882   // Can only occurs for return, but harmless otherwise.
3883   if (Ty->isVoidType())
3884     return ABIArgInfo::getIgnore();
3885 
3886   // Large vector types should be returned via memory. There's no such concept
3887   // in the ABI, but they'd be over 16 bytes anyway so no matter how they're
3888   // classified they'd go into memory (see B.3).
3889   if (Ty->isVectorType() && getContext().getTypeSize(Ty) > 128) {
3890     if (FreeIntRegs > 0)
3891       --FreeIntRegs;
3892     return ABIArgInfo::getIndirect(0, /*ByVal=*/false);
3893   }
3894 
3895   // All non-aggregate LLVM types have a concrete ABI representation so they can
3896   // be passed directly. After this block we're guaranteed to be in a
3897   // complicated case.
3898   if (!isAggregateTypeForABI(Ty)) {
3899     // Treat an enum type as its underlying type.
3900     if (const EnumType *EnumTy = Ty->getAs<EnumType>())
3901       Ty = EnumTy->getDecl()->getIntegerType();
3902 
3903     if (Ty->isFloatingType() || Ty->isVectorType())
3904       return tryUseRegs(Ty, FreeVFPRegs, /*RegsNeeded=*/ 1, /*IsInt=*/ false);
3905 
3906     assert(getContext().getTypeSize(Ty) <= 128 &&
3907            "unexpectedly large scalar type");
3908 
3909     int RegsNeeded = getContext().getTypeSize(Ty) > 64 ? 2 : 1;
3910 
3911     // If the type may need padding registers to ensure "alignment", we must be
3912     // careful when this is accounted for. Increasing the effective size covers
3913     // all cases.
3914     if (getContext().getTypeAlign(Ty) == 128)
3915       RegsNeeded += FreeIntRegs % 2 != 0;
3916 
3917     return tryUseRegs(Ty, FreeIntRegs, RegsNeeded, /*IsInt=*/ true);
3918   }
3919 
3920   if (CGCXXABI::RecordArgABI RAA = getRecordArgABI(Ty, getCXXABI())) {
3921     if (FreeIntRegs > 0 && RAA == CGCXXABI::RAA_Indirect)
3922       --FreeIntRegs;
3923     return ABIArgInfo::getIndirect(0, RAA == CGCXXABI::RAA_DirectInMemory);
3924   }
3925 
3926   if (isEmptyRecord(getContext(), Ty, true)) {
3927     if (!getContext().getLangOpts().CPlusPlus) {
3928       // Empty structs outside C++ mode are a GNU extension, so no ABI can
3929       // possibly tell us what to do. It turns out (I believe) that GCC ignores
3930       // the object for parameter-passsing purposes.
3931       return ABIArgInfo::getIgnore();
3932     }
3933 
3934     // The combination of C++98 9p5 (sizeof(struct) != 0) and the pseudocode
3935     // description of va_arg in the PCS require that an empty struct does
3936     // actually occupy space for parameter-passing. I'm hoping for a
3937     // clarification giving an explicit paragraph to point to in future.
3938     return tryUseRegs(Ty, FreeIntRegs, /*RegsNeeded=*/ 1, /*IsInt=*/ true,
3939                       llvm::Type::getInt8Ty(getVMContext()));
3940   }
3941 
3942   // Homogeneous vector aggregates get passed in registers or on the stack.
3943   const Type *Base = 0;
3944   uint64_t NumMembers = 0;
3945   if (isHomogeneousAggregate(Ty, Base, getContext(), &NumMembers)) {
3946     assert(Base && "Base class should be set for homogeneous aggregate");
3947     // Homogeneous aggregates are passed and returned directly.
3948     return tryUseRegs(Ty, FreeVFPRegs, /*RegsNeeded=*/ NumMembers,
3949                       /*IsInt=*/ false);
3950   }
3951 
3952   uint64_t Size = getContext().getTypeSize(Ty);
3953   if (Size <= 128) {
3954     // Small structs can use the same direct type whether they're in registers
3955     // or on the stack.
3956     llvm::Type *BaseTy;
3957     unsigned NumBases;
3958     int SizeInRegs = (Size + 63) / 64;
3959 
3960     if (getContext().getTypeAlign(Ty) == 128) {
3961       BaseTy = llvm::Type::getIntNTy(getVMContext(), 128);
3962       NumBases = 1;
3963 
3964       // If the type may need padding registers to ensure "alignment", we must
3965       // be careful when this is accounted for. Increasing the effective size
3966       // covers all cases.
3967       SizeInRegs += FreeIntRegs % 2 != 0;
3968     } else {
3969       BaseTy = llvm::Type::getInt64Ty(getVMContext());
3970       NumBases = SizeInRegs;
3971     }
3972     llvm::Type *DirectTy = llvm::ArrayType::get(BaseTy, NumBases);
3973 
3974     return tryUseRegs(Ty, FreeIntRegs, /*RegsNeeded=*/ SizeInRegs,
3975                       /*IsInt=*/ true, DirectTy);
3976   }
3977 
3978   // If the aggregate is > 16 bytes, it's passed and returned indirectly. In
3979   // LLVM terms the return uses an "sret" pointer, but that's handled elsewhere.
3980   --FreeIntRegs;
3981   return ABIArgInfo::getIndirect(0, /* byVal = */ false);
3982 }
3983 
3984 llvm::Value *AArch64ABIInfo::EmitVAArg(llvm::Value *VAListAddr, QualType Ty,
3985                                        CodeGenFunction &CGF) const {
3986   // The AArch64 va_list type and handling is specified in the Procedure Call
3987   // Standard, section B.4:
3988   //
3989   // struct {
3990   //   void *__stack;
3991   //   void *__gr_top;
3992   //   void *__vr_top;
3993   //   int __gr_offs;
3994   //   int __vr_offs;
3995   // };
3996 
3997   assert(!CGF.CGM.getDataLayout().isBigEndian()
3998          && "va_arg not implemented for big-endian AArch64");
3999 
4000   int FreeIntRegs = 8, FreeVFPRegs = 8;
4001   Ty = CGF.getContext().getCanonicalType(Ty);
4002   ABIArgInfo AI = classifyGenericType(Ty, FreeIntRegs, FreeVFPRegs);
4003 
4004   llvm::BasicBlock *MaybeRegBlock = CGF.createBasicBlock("vaarg.maybe_reg");
4005   llvm::BasicBlock *InRegBlock = CGF.createBasicBlock("vaarg.in_reg");
4006   llvm::BasicBlock *OnStackBlock = CGF.createBasicBlock("vaarg.on_stack");
4007   llvm::BasicBlock *ContBlock = CGF.createBasicBlock("vaarg.end");
4008 
4009   llvm::Value *reg_offs_p = 0, *reg_offs = 0;
4010   int reg_top_index;
4011   int RegSize;
4012   if (FreeIntRegs < 8) {
4013     assert(FreeVFPRegs == 8 && "Arguments never split between int & VFP regs");
4014     // 3 is the field number of __gr_offs
4015     reg_offs_p = CGF.Builder.CreateStructGEP(VAListAddr, 3, "gr_offs_p");
4016     reg_offs = CGF.Builder.CreateLoad(reg_offs_p, "gr_offs");
4017     reg_top_index = 1; // field number for __gr_top
4018     RegSize = 8 * (8 - FreeIntRegs);
4019   } else {
4020     assert(FreeVFPRegs < 8 && "Argument must go in VFP or int regs");
4021     // 4 is the field number of __vr_offs.
4022     reg_offs_p = CGF.Builder.CreateStructGEP(VAListAddr, 4, "vr_offs_p");
4023     reg_offs = CGF.Builder.CreateLoad(reg_offs_p, "vr_offs");
4024     reg_top_index = 2; // field number for __vr_top
4025     RegSize = 16 * (8 - FreeVFPRegs);
4026   }
4027 
4028   //=======================================
4029   // Find out where argument was passed
4030   //=======================================
4031 
4032   // If reg_offs >= 0 we're already using the stack for this type of
4033   // argument. We don't want to keep updating reg_offs (in case it overflows,
4034   // though anyone passing 2GB of arguments, each at most 16 bytes, deserves
4035   // whatever they get).
4036   llvm::Value *UsingStack = 0;
4037   UsingStack = CGF.Builder.CreateICmpSGE(reg_offs,
4038                                          llvm::ConstantInt::get(CGF.Int32Ty, 0));
4039 
4040   CGF.Builder.CreateCondBr(UsingStack, OnStackBlock, MaybeRegBlock);
4041 
4042   // Otherwise, at least some kind of argument could go in these registers, the
4043   // quesiton is whether this particular type is too big.
4044   CGF.EmitBlock(MaybeRegBlock);
4045 
4046   // Integer arguments may need to correct register alignment (for example a
4047   // "struct { __int128 a; };" gets passed in x_2N, x_{2N+1}). In this case we
4048   // align __gr_offs to calculate the potential address.
4049   if (FreeIntRegs < 8 && AI.isDirect() && getContext().getTypeAlign(Ty) > 64) {
4050     int Align = getContext().getTypeAlign(Ty) / 8;
4051 
4052     reg_offs = CGF.Builder.CreateAdd(reg_offs,
4053                                  llvm::ConstantInt::get(CGF.Int32Ty, Align - 1),
4054                                  "align_regoffs");
4055     reg_offs = CGF.Builder.CreateAnd(reg_offs,
4056                                     llvm::ConstantInt::get(CGF.Int32Ty, -Align),
4057                                     "aligned_regoffs");
4058   }
4059 
4060   // Update the gr_offs/vr_offs pointer for next call to va_arg on this va_list.
4061   llvm::Value *NewOffset = 0;
4062   NewOffset = CGF.Builder.CreateAdd(reg_offs,
4063                                     llvm::ConstantInt::get(CGF.Int32Ty, RegSize),
4064                                     "new_reg_offs");
4065   CGF.Builder.CreateStore(NewOffset, reg_offs_p);
4066 
4067   // Now we're in a position to decide whether this argument really was in
4068   // registers or not.
4069   llvm::Value *InRegs = 0;
4070   InRegs = CGF.Builder.CreateICmpSLE(NewOffset,
4071                                      llvm::ConstantInt::get(CGF.Int32Ty, 0),
4072                                      "inreg");
4073 
4074   CGF.Builder.CreateCondBr(InRegs, InRegBlock, OnStackBlock);
4075 
4076   //=======================================
4077   // Argument was in registers
4078   //=======================================
4079 
4080   // Now we emit the code for if the argument was originally passed in
4081   // registers. First start the appropriate block:
4082   CGF.EmitBlock(InRegBlock);
4083 
4084   llvm::Value *reg_top_p = 0, *reg_top = 0;
4085   reg_top_p = CGF.Builder.CreateStructGEP(VAListAddr, reg_top_index, "reg_top_p");
4086   reg_top = CGF.Builder.CreateLoad(reg_top_p, "reg_top");
4087   llvm::Value *BaseAddr = CGF.Builder.CreateGEP(reg_top, reg_offs);
4088   llvm::Value *RegAddr = 0;
4089   llvm::Type *MemTy = llvm::PointerType::getUnqual(CGF.ConvertTypeForMem(Ty));
4090 
4091   if (!AI.isDirect()) {
4092     // If it's been passed indirectly (actually a struct), whatever we find from
4093     // stored registers or on the stack will actually be a struct **.
4094     MemTy = llvm::PointerType::getUnqual(MemTy);
4095   }
4096 
4097   const Type *Base = 0;
4098   uint64_t NumMembers;
4099   if (isHomogeneousAggregate(Ty, Base, getContext(), &NumMembers)
4100       && NumMembers > 1) {
4101     // Homogeneous aggregates passed in registers will have their elements split
4102     // and stored 16-bytes apart regardless of size (they're notionally in qN,
4103     // qN+1, ...). We reload and store into a temporary local variable
4104     // contiguously.
4105     assert(AI.isDirect() && "Homogeneous aggregates should be passed directly");
4106     llvm::Type *BaseTy = CGF.ConvertType(QualType(Base, 0));
4107     llvm::Type *HFATy = llvm::ArrayType::get(BaseTy, NumMembers);
4108     llvm::Value *Tmp = CGF.CreateTempAlloca(HFATy);
4109 
4110     for (unsigned i = 0; i < NumMembers; ++i) {
4111       llvm::Value *BaseOffset = llvm::ConstantInt::get(CGF.Int32Ty, 16 * i);
4112       llvm::Value *LoadAddr = CGF.Builder.CreateGEP(BaseAddr, BaseOffset);
4113       LoadAddr = CGF.Builder.CreateBitCast(LoadAddr,
4114                                            llvm::PointerType::getUnqual(BaseTy));
4115       llvm::Value *StoreAddr = CGF.Builder.CreateStructGEP(Tmp, i);
4116 
4117       llvm::Value *Elem = CGF.Builder.CreateLoad(LoadAddr);
4118       CGF.Builder.CreateStore(Elem, StoreAddr);
4119     }
4120 
4121     RegAddr = CGF.Builder.CreateBitCast(Tmp, MemTy);
4122   } else {
4123     // Otherwise the object is contiguous in memory
4124     RegAddr = CGF.Builder.CreateBitCast(BaseAddr, MemTy);
4125   }
4126 
4127   CGF.EmitBranch(ContBlock);
4128 
4129   //=======================================
4130   // Argument was on the stack
4131   //=======================================
4132   CGF.EmitBlock(OnStackBlock);
4133 
4134   llvm::Value *stack_p = 0, *OnStackAddr = 0;
4135   stack_p = CGF.Builder.CreateStructGEP(VAListAddr, 0, "stack_p");
4136   OnStackAddr = CGF.Builder.CreateLoad(stack_p, "stack");
4137 
4138   // Again, stack arguments may need realigmnent. In this case both integer and
4139   // floating-point ones might be affected.
4140   if (AI.isDirect() && getContext().getTypeAlign(Ty) > 64) {
4141     int Align = getContext().getTypeAlign(Ty) / 8;
4142 
4143     OnStackAddr = CGF.Builder.CreatePtrToInt(OnStackAddr, CGF.Int64Ty);
4144 
4145     OnStackAddr = CGF.Builder.CreateAdd(OnStackAddr,
4146                                  llvm::ConstantInt::get(CGF.Int64Ty, Align - 1),
4147                                  "align_stack");
4148     OnStackAddr = CGF.Builder.CreateAnd(OnStackAddr,
4149                                     llvm::ConstantInt::get(CGF.Int64Ty, -Align),
4150                                     "align_stack");
4151 
4152     OnStackAddr = CGF.Builder.CreateIntToPtr(OnStackAddr, CGF.Int8PtrTy);
4153   }
4154 
4155   uint64_t StackSize;
4156   if (AI.isDirect())
4157     StackSize = getContext().getTypeSize(Ty) / 8;
4158   else
4159     StackSize = 8;
4160 
4161   // All stack slots are 8 bytes
4162   StackSize = llvm::RoundUpToAlignment(StackSize, 8);
4163 
4164   llvm::Value *StackSizeC = llvm::ConstantInt::get(CGF.Int32Ty, StackSize);
4165   llvm::Value *NewStack = CGF.Builder.CreateGEP(OnStackAddr, StackSizeC,
4166                                                 "new_stack");
4167 
4168   // Write the new value of __stack for the next call to va_arg
4169   CGF.Builder.CreateStore(NewStack, stack_p);
4170 
4171   OnStackAddr = CGF.Builder.CreateBitCast(OnStackAddr, MemTy);
4172 
4173   CGF.EmitBranch(ContBlock);
4174 
4175   //=======================================
4176   // Tidy up
4177   //=======================================
4178   CGF.EmitBlock(ContBlock);
4179 
4180   llvm::PHINode *ResAddr = CGF.Builder.CreatePHI(MemTy, 2, "vaarg.addr");
4181   ResAddr->addIncoming(RegAddr, InRegBlock);
4182   ResAddr->addIncoming(OnStackAddr, OnStackBlock);
4183 
4184   if (AI.isDirect())
4185     return ResAddr;
4186 
4187   return CGF.Builder.CreateLoad(ResAddr, "vaarg.addr");
4188 }
4189 
4190 //===----------------------------------------------------------------------===//
4191 // NVPTX ABI Implementation
4192 //===----------------------------------------------------------------------===//
4193 
4194 namespace {
4195 
4196 class NVPTXABIInfo : public ABIInfo {
4197 public:
4198   NVPTXABIInfo(CodeGenTypes &CGT) : ABIInfo(CGT) {}
4199 
4200   ABIArgInfo classifyReturnType(QualType RetTy) const;
4201   ABIArgInfo classifyArgumentType(QualType Ty) const;
4202 
4203   virtual void computeInfo(CGFunctionInfo &FI) const;
4204   virtual llvm::Value *EmitVAArg(llvm::Value *VAListAddr, QualType Ty,
4205                                  CodeGenFunction &CFG) const;
4206 };
4207 
4208 class NVPTXTargetCodeGenInfo : public TargetCodeGenInfo {
4209 public:
4210   NVPTXTargetCodeGenInfo(CodeGenTypes &CGT)
4211     : TargetCodeGenInfo(new NVPTXABIInfo(CGT)) {}
4212 
4213   virtual void SetTargetAttributes(const Decl *D, llvm::GlobalValue *GV,
4214                                    CodeGen::CodeGenModule &M) const;
4215 private:
4216   static void addKernelMetadata(llvm::Function *F);
4217 };
4218 
4219 ABIArgInfo NVPTXABIInfo::classifyReturnType(QualType RetTy) const {
4220   if (RetTy->isVoidType())
4221     return ABIArgInfo::getIgnore();
4222 
4223   // note: this is different from default ABI
4224   if (!RetTy->isScalarType())
4225     return ABIArgInfo::getDirect();
4226 
4227   // Treat an enum type as its underlying type.
4228   if (const EnumType *EnumTy = RetTy->getAs<EnumType>())
4229     RetTy = EnumTy->getDecl()->getIntegerType();
4230 
4231   return (RetTy->isPromotableIntegerType() ?
4232           ABIArgInfo::getExtend() : ABIArgInfo::getDirect());
4233 }
4234 
4235 ABIArgInfo NVPTXABIInfo::classifyArgumentType(QualType Ty) const {
4236   // Treat an enum type as its underlying type.
4237   if (const EnumType *EnumTy = Ty->getAs<EnumType>())
4238     Ty = EnumTy->getDecl()->getIntegerType();
4239 
4240   return (Ty->isPromotableIntegerType() ?
4241           ABIArgInfo::getExtend() : ABIArgInfo::getDirect());
4242 }
4243 
4244 void NVPTXABIInfo::computeInfo(CGFunctionInfo &FI) const {
4245   FI.getReturnInfo() = classifyReturnType(FI.getReturnType());
4246   for (CGFunctionInfo::arg_iterator it = FI.arg_begin(), ie = FI.arg_end();
4247        it != ie; ++it)
4248     it->info = classifyArgumentType(it->type);
4249 
4250   // Always honor user-specified calling convention.
4251   if (FI.getCallingConvention() != llvm::CallingConv::C)
4252     return;
4253 
4254   FI.setEffectiveCallingConvention(getRuntimeCC());
4255 }
4256 
4257 llvm::Value *NVPTXABIInfo::EmitVAArg(llvm::Value *VAListAddr, QualType Ty,
4258                                      CodeGenFunction &CFG) const {
4259   llvm_unreachable("NVPTX does not support varargs");
4260 }
4261 
4262 void NVPTXTargetCodeGenInfo::
4263 SetTargetAttributes(const Decl *D, llvm::GlobalValue *GV,
4264                     CodeGen::CodeGenModule &M) const{
4265   const FunctionDecl *FD = dyn_cast<FunctionDecl>(D);
4266   if (!FD) return;
4267 
4268   llvm::Function *F = cast<llvm::Function>(GV);
4269 
4270   // Perform special handling in OpenCL mode
4271   if (M.getLangOpts().OpenCL) {
4272     // Use OpenCL function attributes to check for kernel functions
4273     // By default, all functions are device functions
4274     if (FD->hasAttr<OpenCLKernelAttr>()) {
4275       // OpenCL __kernel functions get kernel metadata
4276       addKernelMetadata(F);
4277       // And kernel functions are not subject to inlining
4278       F->addFnAttr(llvm::Attribute::NoInline);
4279     }
4280   }
4281 
4282   // Perform special handling in CUDA mode.
4283   if (M.getLangOpts().CUDA) {
4284     // CUDA __global__ functions get a kernel metadata entry.  Since
4285     // __global__ functions cannot be called from the device, we do not
4286     // need to set the noinline attribute.
4287     if (FD->hasAttr<CUDAGlobalAttr>())
4288       addKernelMetadata(F);
4289   }
4290 }
4291 
4292 void NVPTXTargetCodeGenInfo::addKernelMetadata(llvm::Function *F) {
4293   llvm::Module *M = F->getParent();
4294   llvm::LLVMContext &Ctx = M->getContext();
4295 
4296   // Get "nvvm.annotations" metadata node
4297   llvm::NamedMDNode *MD = M->getOrInsertNamedMetadata("nvvm.annotations");
4298 
4299   // Create !{<func-ref>, metadata !"kernel", i32 1} node
4300   llvm::SmallVector<llvm::Value *, 3> MDVals;
4301   MDVals.push_back(F);
4302   MDVals.push_back(llvm::MDString::get(Ctx, "kernel"));
4303   MDVals.push_back(llvm::ConstantInt::get(llvm::Type::getInt32Ty(Ctx), 1));
4304 
4305   // Append metadata to nvvm.annotations
4306   MD->addOperand(llvm::MDNode::get(Ctx, MDVals));
4307 }
4308 
4309 }
4310 
4311 //===----------------------------------------------------------------------===//
4312 // SystemZ ABI Implementation
4313 //===----------------------------------------------------------------------===//
4314 
4315 namespace {
4316 
4317 class SystemZABIInfo : public ABIInfo {
4318 public:
4319   SystemZABIInfo(CodeGenTypes &CGT) : ABIInfo(CGT) {}
4320 
4321   bool isPromotableIntegerType(QualType Ty) const;
4322   bool isCompoundType(QualType Ty) const;
4323   bool isFPArgumentType(QualType Ty) const;
4324 
4325   ABIArgInfo classifyReturnType(QualType RetTy) const;
4326   ABIArgInfo classifyArgumentType(QualType ArgTy) const;
4327 
4328   virtual void computeInfo(CGFunctionInfo &FI) const {
4329     FI.getReturnInfo() = classifyReturnType(FI.getReturnType());
4330     for (CGFunctionInfo::arg_iterator it = FI.arg_begin(), ie = FI.arg_end();
4331          it != ie; ++it)
4332       it->info = classifyArgumentType(it->type);
4333   }
4334 
4335   virtual llvm::Value *EmitVAArg(llvm::Value *VAListAddr, QualType Ty,
4336                                  CodeGenFunction &CGF) const;
4337 };
4338 
4339 class SystemZTargetCodeGenInfo : public TargetCodeGenInfo {
4340 public:
4341   SystemZTargetCodeGenInfo(CodeGenTypes &CGT)
4342     : TargetCodeGenInfo(new SystemZABIInfo(CGT)) {}
4343 };
4344 
4345 }
4346 
4347 bool SystemZABIInfo::isPromotableIntegerType(QualType Ty) const {
4348   // Treat an enum type as its underlying type.
4349   if (const EnumType *EnumTy = Ty->getAs<EnumType>())
4350     Ty = EnumTy->getDecl()->getIntegerType();
4351 
4352   // Promotable integer types are required to be promoted by the ABI.
4353   if (Ty->isPromotableIntegerType())
4354     return true;
4355 
4356   // 32-bit values must also be promoted.
4357   if (const BuiltinType *BT = Ty->getAs<BuiltinType>())
4358     switch (BT->getKind()) {
4359     case BuiltinType::Int:
4360     case BuiltinType::UInt:
4361       return true;
4362     default:
4363       return false;
4364     }
4365   return false;
4366 }
4367 
4368 bool SystemZABIInfo::isCompoundType(QualType Ty) const {
4369   return Ty->isAnyComplexType() || isAggregateTypeForABI(Ty);
4370 }
4371 
4372 bool SystemZABIInfo::isFPArgumentType(QualType Ty) const {
4373   if (const BuiltinType *BT = Ty->getAs<BuiltinType>())
4374     switch (BT->getKind()) {
4375     case BuiltinType::Float:
4376     case BuiltinType::Double:
4377       return true;
4378     default:
4379       return false;
4380     }
4381 
4382   if (const RecordType *RT = Ty->getAsStructureType()) {
4383     const RecordDecl *RD = RT->getDecl();
4384     bool Found = false;
4385 
4386     // If this is a C++ record, check the bases first.
4387     if (const CXXRecordDecl *CXXRD = dyn_cast<CXXRecordDecl>(RD))
4388       for (CXXRecordDecl::base_class_const_iterator I = CXXRD->bases_begin(),
4389              E = CXXRD->bases_end(); I != E; ++I) {
4390         QualType Base = I->getType();
4391 
4392         // Empty bases don't affect things either way.
4393         if (isEmptyRecord(getContext(), Base, true))
4394           continue;
4395 
4396         if (Found)
4397           return false;
4398         Found = isFPArgumentType(Base);
4399         if (!Found)
4400           return false;
4401       }
4402 
4403     // Check the fields.
4404     for (RecordDecl::field_iterator I = RD->field_begin(),
4405            E = RD->field_end(); I != E; ++I) {
4406       const FieldDecl *FD = *I;
4407 
4408       // Empty bitfields don't affect things either way.
4409       // Unlike isSingleElementStruct(), empty structure and array fields
4410       // do count.  So do anonymous bitfields that aren't zero-sized.
4411       if (FD->isBitField() && FD->getBitWidthValue(getContext()) == 0)
4412         return true;
4413 
4414       // Unlike isSingleElementStruct(), arrays do not count.
4415       // Nested isFPArgumentType structures still do though.
4416       if (Found)
4417         return false;
4418       Found = isFPArgumentType(FD->getType());
4419       if (!Found)
4420         return false;
4421     }
4422 
4423     // Unlike isSingleElementStruct(), trailing padding is allowed.
4424     // An 8-byte aligned struct s { float f; } is passed as a double.
4425     return Found;
4426   }
4427 
4428   return false;
4429 }
4430 
4431 llvm::Value *SystemZABIInfo::EmitVAArg(llvm::Value *VAListAddr, QualType Ty,
4432                                        CodeGenFunction &CGF) const {
4433   // Assume that va_list type is correct; should be pointer to LLVM type:
4434   // struct {
4435   //   i64 __gpr;
4436   //   i64 __fpr;
4437   //   i8 *__overflow_arg_area;
4438   //   i8 *__reg_save_area;
4439   // };
4440 
4441   // Every argument occupies 8 bytes and is passed by preference in either
4442   // GPRs or FPRs.
4443   Ty = CGF.getContext().getCanonicalType(Ty);
4444   ABIArgInfo AI = classifyArgumentType(Ty);
4445   bool InFPRs = isFPArgumentType(Ty);
4446 
4447   llvm::Type *APTy = llvm::PointerType::getUnqual(CGF.ConvertTypeForMem(Ty));
4448   bool IsIndirect = AI.isIndirect();
4449   unsigned UnpaddedBitSize;
4450   if (IsIndirect) {
4451     APTy = llvm::PointerType::getUnqual(APTy);
4452     UnpaddedBitSize = 64;
4453   } else
4454     UnpaddedBitSize = getContext().getTypeSize(Ty);
4455   unsigned PaddedBitSize = 64;
4456   assert((UnpaddedBitSize <= PaddedBitSize) && "Invalid argument size.");
4457 
4458   unsigned PaddedSize = PaddedBitSize / 8;
4459   unsigned Padding = (PaddedBitSize - UnpaddedBitSize) / 8;
4460 
4461   unsigned MaxRegs, RegCountField, RegSaveIndex, RegPadding;
4462   if (InFPRs) {
4463     MaxRegs = 4; // Maximum of 4 FPR arguments
4464     RegCountField = 1; // __fpr
4465     RegSaveIndex = 16; // save offset for f0
4466     RegPadding = 0; // floats are passed in the high bits of an FPR
4467   } else {
4468     MaxRegs = 5; // Maximum of 5 GPR arguments
4469     RegCountField = 0; // __gpr
4470     RegSaveIndex = 2; // save offset for r2
4471     RegPadding = Padding; // values are passed in the low bits of a GPR
4472   }
4473 
4474   llvm::Value *RegCountPtr =
4475     CGF.Builder.CreateStructGEP(VAListAddr, RegCountField, "reg_count_ptr");
4476   llvm::Value *RegCount = CGF.Builder.CreateLoad(RegCountPtr, "reg_count");
4477   llvm::Type *IndexTy = RegCount->getType();
4478   llvm::Value *MaxRegsV = llvm::ConstantInt::get(IndexTy, MaxRegs);
4479   llvm::Value *InRegs = CGF.Builder.CreateICmpULT(RegCount, MaxRegsV,
4480 						  "fits_in_regs");
4481 
4482   llvm::BasicBlock *InRegBlock = CGF.createBasicBlock("vaarg.in_reg");
4483   llvm::BasicBlock *InMemBlock = CGF.createBasicBlock("vaarg.in_mem");
4484   llvm::BasicBlock *ContBlock = CGF.createBasicBlock("vaarg.end");
4485   CGF.Builder.CreateCondBr(InRegs, InRegBlock, InMemBlock);
4486 
4487   // Emit code to load the value if it was passed in registers.
4488   CGF.EmitBlock(InRegBlock);
4489 
4490   // Work out the address of an argument register.
4491   llvm::Value *PaddedSizeV = llvm::ConstantInt::get(IndexTy, PaddedSize);
4492   llvm::Value *ScaledRegCount =
4493     CGF.Builder.CreateMul(RegCount, PaddedSizeV, "scaled_reg_count");
4494   llvm::Value *RegBase =
4495     llvm::ConstantInt::get(IndexTy, RegSaveIndex * PaddedSize + RegPadding);
4496   llvm::Value *RegOffset =
4497     CGF.Builder.CreateAdd(ScaledRegCount, RegBase, "reg_offset");
4498   llvm::Value *RegSaveAreaPtr =
4499     CGF.Builder.CreateStructGEP(VAListAddr, 3, "reg_save_area_ptr");
4500   llvm::Value *RegSaveArea =
4501     CGF.Builder.CreateLoad(RegSaveAreaPtr, "reg_save_area");
4502   llvm::Value *RawRegAddr =
4503     CGF.Builder.CreateGEP(RegSaveArea, RegOffset, "raw_reg_addr");
4504   llvm::Value *RegAddr =
4505     CGF.Builder.CreateBitCast(RawRegAddr, APTy, "reg_addr");
4506 
4507   // Update the register count
4508   llvm::Value *One = llvm::ConstantInt::get(IndexTy, 1);
4509   llvm::Value *NewRegCount =
4510     CGF.Builder.CreateAdd(RegCount, One, "reg_count");
4511   CGF.Builder.CreateStore(NewRegCount, RegCountPtr);
4512   CGF.EmitBranch(ContBlock);
4513 
4514   // Emit code to load the value if it was passed in memory.
4515   CGF.EmitBlock(InMemBlock);
4516 
4517   // Work out the address of a stack argument.
4518   llvm::Value *OverflowArgAreaPtr =
4519     CGF.Builder.CreateStructGEP(VAListAddr, 2, "overflow_arg_area_ptr");
4520   llvm::Value *OverflowArgArea =
4521     CGF.Builder.CreateLoad(OverflowArgAreaPtr, "overflow_arg_area");
4522   llvm::Value *PaddingV = llvm::ConstantInt::get(IndexTy, Padding);
4523   llvm::Value *RawMemAddr =
4524     CGF.Builder.CreateGEP(OverflowArgArea, PaddingV, "raw_mem_addr");
4525   llvm::Value *MemAddr =
4526     CGF.Builder.CreateBitCast(RawMemAddr, APTy, "mem_addr");
4527 
4528   // Update overflow_arg_area_ptr pointer
4529   llvm::Value *NewOverflowArgArea =
4530     CGF.Builder.CreateGEP(OverflowArgArea, PaddedSizeV, "overflow_arg_area");
4531   CGF.Builder.CreateStore(NewOverflowArgArea, OverflowArgAreaPtr);
4532   CGF.EmitBranch(ContBlock);
4533 
4534   // Return the appropriate result.
4535   CGF.EmitBlock(ContBlock);
4536   llvm::PHINode *ResAddr = CGF.Builder.CreatePHI(APTy, 2, "va_arg.addr");
4537   ResAddr->addIncoming(RegAddr, InRegBlock);
4538   ResAddr->addIncoming(MemAddr, InMemBlock);
4539 
4540   if (IsIndirect)
4541     return CGF.Builder.CreateLoad(ResAddr, "indirect_arg");
4542 
4543   return ResAddr;
4544 }
4545 
4546 bool X86_32TargetCodeGenInfo::isStructReturnInRegABI(
4547     const llvm::Triple &Triple, const CodeGenOptions &Opts) {
4548   assert(Triple.getArch() == llvm::Triple::x86);
4549 
4550   switch (Opts.getStructReturnConvention()) {
4551   case CodeGenOptions::SRCK_Default:
4552     break;
4553   case CodeGenOptions::SRCK_OnStack:  // -fpcc-struct-return
4554     return false;
4555   case CodeGenOptions::SRCK_InRegs:  // -freg-struct-return
4556     return true;
4557   }
4558 
4559   if (Triple.isOSDarwin())
4560     return true;
4561 
4562   switch (Triple.getOS()) {
4563   case llvm::Triple::Cygwin:
4564   case llvm::Triple::MinGW32:
4565   case llvm::Triple::AuroraUX:
4566   case llvm::Triple::DragonFly:
4567   case llvm::Triple::FreeBSD:
4568   case llvm::Triple::OpenBSD:
4569   case llvm::Triple::Bitrig:
4570   case llvm::Triple::Win32:
4571     return true;
4572   default:
4573     return false;
4574   }
4575 }
4576 
4577 ABIArgInfo SystemZABIInfo::classifyReturnType(QualType RetTy) const {
4578   if (RetTy->isVoidType())
4579     return ABIArgInfo::getIgnore();
4580   if (isCompoundType(RetTy) || getContext().getTypeSize(RetTy) > 64)
4581     return ABIArgInfo::getIndirect(0);
4582   return (isPromotableIntegerType(RetTy) ?
4583           ABIArgInfo::getExtend() : ABIArgInfo::getDirect());
4584 }
4585 
4586 ABIArgInfo SystemZABIInfo::classifyArgumentType(QualType Ty) const {
4587   // Handle the generic C++ ABI.
4588   if (CGCXXABI::RecordArgABI RAA = getRecordArgABI(Ty, getCXXABI()))
4589     return ABIArgInfo::getIndirect(0, RAA == CGCXXABI::RAA_DirectInMemory);
4590 
4591   // Integers and enums are extended to full register width.
4592   if (isPromotableIntegerType(Ty))
4593     return ABIArgInfo::getExtend();
4594 
4595   // Values that are not 1, 2, 4 or 8 bytes in size are passed indirectly.
4596   uint64_t Size = getContext().getTypeSize(Ty);
4597   if (Size != 8 && Size != 16 && Size != 32 && Size != 64)
4598     return ABIArgInfo::getIndirect(0, /*ByVal=*/false);
4599 
4600   // Handle small structures.
4601   if (const RecordType *RT = Ty->getAs<RecordType>()) {
4602     // Structures with flexible arrays have variable length, so really
4603     // fail the size test above.
4604     const RecordDecl *RD = RT->getDecl();
4605     if (RD->hasFlexibleArrayMember())
4606       return ABIArgInfo::getIndirect(0, /*ByVal=*/false);
4607 
4608     // The structure is passed as an unextended integer, a float, or a double.
4609     llvm::Type *PassTy;
4610     if (isFPArgumentType(Ty)) {
4611       assert(Size == 32 || Size == 64);
4612       if (Size == 32)
4613         PassTy = llvm::Type::getFloatTy(getVMContext());
4614       else
4615         PassTy = llvm::Type::getDoubleTy(getVMContext());
4616     } else
4617       PassTy = llvm::IntegerType::get(getVMContext(), Size);
4618     return ABIArgInfo::getDirect(PassTy);
4619   }
4620 
4621   // Non-structure compounds are passed indirectly.
4622   if (isCompoundType(Ty))
4623     return ABIArgInfo::getIndirect(0, /*ByVal=*/false);
4624 
4625   return ABIArgInfo::getDirect(0);
4626 }
4627 
4628 //===----------------------------------------------------------------------===//
4629 // MSP430 ABI Implementation
4630 //===----------------------------------------------------------------------===//
4631 
4632 namespace {
4633 
4634 class MSP430TargetCodeGenInfo : public TargetCodeGenInfo {
4635 public:
4636   MSP430TargetCodeGenInfo(CodeGenTypes &CGT)
4637     : TargetCodeGenInfo(new DefaultABIInfo(CGT)) {}
4638   void SetTargetAttributes(const Decl *D, llvm::GlobalValue *GV,
4639                            CodeGen::CodeGenModule &M) const;
4640 };
4641 
4642 }
4643 
4644 void MSP430TargetCodeGenInfo::SetTargetAttributes(const Decl *D,
4645                                                   llvm::GlobalValue *GV,
4646                                              CodeGen::CodeGenModule &M) const {
4647   if (const FunctionDecl *FD = dyn_cast<FunctionDecl>(D)) {
4648     if (const MSP430InterruptAttr *attr = FD->getAttr<MSP430InterruptAttr>()) {
4649       // Handle 'interrupt' attribute:
4650       llvm::Function *F = cast<llvm::Function>(GV);
4651 
4652       // Step 1: Set ISR calling convention.
4653       F->setCallingConv(llvm::CallingConv::MSP430_INTR);
4654 
4655       // Step 2: Add attributes goodness.
4656       F->addFnAttr(llvm::Attribute::NoInline);
4657 
4658       // Step 3: Emit ISR vector alias.
4659       unsigned Num = attr->getNumber() / 2;
4660       new llvm::GlobalAlias(GV->getType(), llvm::Function::ExternalLinkage,
4661                             "__isr_" + Twine(Num),
4662                             GV, &M.getModule());
4663     }
4664   }
4665 }
4666 
4667 //===----------------------------------------------------------------------===//
4668 // MIPS ABI Implementation.  This works for both little-endian and
4669 // big-endian variants.
4670 //===----------------------------------------------------------------------===//
4671 
4672 namespace {
4673 class MipsABIInfo : public ABIInfo {
4674   bool IsO32;
4675   unsigned MinABIStackAlignInBytes, StackAlignInBytes;
4676   void CoerceToIntArgs(uint64_t TySize,
4677                        SmallVectorImpl<llvm::Type *> &ArgList) const;
4678   llvm::Type* HandleAggregates(QualType Ty, uint64_t TySize) const;
4679   llvm::Type* returnAggregateInRegs(QualType RetTy, uint64_t Size) const;
4680   llvm::Type* getPaddingType(uint64_t Align, uint64_t Offset) const;
4681 public:
4682   MipsABIInfo(CodeGenTypes &CGT, bool _IsO32) :
4683     ABIInfo(CGT), IsO32(_IsO32), MinABIStackAlignInBytes(IsO32 ? 4 : 8),
4684     StackAlignInBytes(IsO32 ? 8 : 16) {}
4685 
4686   ABIArgInfo classifyReturnType(QualType RetTy) const;
4687   ABIArgInfo classifyArgumentType(QualType RetTy, uint64_t &Offset) const;
4688   virtual void computeInfo(CGFunctionInfo &FI) const;
4689   virtual llvm::Value *EmitVAArg(llvm::Value *VAListAddr, QualType Ty,
4690                                  CodeGenFunction &CGF) const;
4691 };
4692 
4693 class MIPSTargetCodeGenInfo : public TargetCodeGenInfo {
4694   unsigned SizeOfUnwindException;
4695 public:
4696   MIPSTargetCodeGenInfo(CodeGenTypes &CGT, bool IsO32)
4697     : TargetCodeGenInfo(new MipsABIInfo(CGT, IsO32)),
4698       SizeOfUnwindException(IsO32 ? 24 : 32) {}
4699 
4700   int getDwarfEHStackPointer(CodeGen::CodeGenModule &CGM) const {
4701     return 29;
4702   }
4703 
4704   void SetTargetAttributes(const Decl *D, llvm::GlobalValue *GV,
4705                            CodeGen::CodeGenModule &CGM) const {
4706     const FunctionDecl *FD = dyn_cast<FunctionDecl>(D);
4707     if (!FD) return;
4708     llvm::Function *Fn = cast<llvm::Function>(GV);
4709     if (FD->hasAttr<Mips16Attr>()) {
4710       Fn->addFnAttr("mips16");
4711     }
4712     else if (FD->hasAttr<NoMips16Attr>()) {
4713       Fn->addFnAttr("nomips16");
4714     }
4715   }
4716 
4717   bool initDwarfEHRegSizeTable(CodeGen::CodeGenFunction &CGF,
4718                                llvm::Value *Address) const;
4719 
4720   unsigned getSizeOfUnwindException() const {
4721     return SizeOfUnwindException;
4722   }
4723 };
4724 }
4725 
4726 void MipsABIInfo::CoerceToIntArgs(uint64_t TySize,
4727                                   SmallVectorImpl<llvm::Type *> &ArgList) const {
4728   llvm::IntegerType *IntTy =
4729     llvm::IntegerType::get(getVMContext(), MinABIStackAlignInBytes * 8);
4730 
4731   // Add (TySize / MinABIStackAlignInBytes) args of IntTy.
4732   for (unsigned N = TySize / (MinABIStackAlignInBytes * 8); N; --N)
4733     ArgList.push_back(IntTy);
4734 
4735   // If necessary, add one more integer type to ArgList.
4736   unsigned R = TySize % (MinABIStackAlignInBytes * 8);
4737 
4738   if (R)
4739     ArgList.push_back(llvm::IntegerType::get(getVMContext(), R));
4740 }
4741 
4742 // In N32/64, an aligned double precision floating point field is passed in
4743 // a register.
4744 llvm::Type* MipsABIInfo::HandleAggregates(QualType Ty, uint64_t TySize) const {
4745   SmallVector<llvm::Type*, 8> ArgList, IntArgList;
4746 
4747   if (IsO32) {
4748     CoerceToIntArgs(TySize, ArgList);
4749     return llvm::StructType::get(getVMContext(), ArgList);
4750   }
4751 
4752   if (Ty->isComplexType())
4753     return CGT.ConvertType(Ty);
4754 
4755   const RecordType *RT = Ty->getAs<RecordType>();
4756 
4757   // Unions/vectors are passed in integer registers.
4758   if (!RT || !RT->isStructureOrClassType()) {
4759     CoerceToIntArgs(TySize, ArgList);
4760     return llvm::StructType::get(getVMContext(), ArgList);
4761   }
4762 
4763   const RecordDecl *RD = RT->getDecl();
4764   const ASTRecordLayout &Layout = getContext().getASTRecordLayout(RD);
4765   assert(!(TySize % 8) && "Size of structure must be multiple of 8.");
4766 
4767   uint64_t LastOffset = 0;
4768   unsigned idx = 0;
4769   llvm::IntegerType *I64 = llvm::IntegerType::get(getVMContext(), 64);
4770 
4771   // Iterate over fields in the struct/class and check if there are any aligned
4772   // double fields.
4773   for (RecordDecl::field_iterator i = RD->field_begin(), e = RD->field_end();
4774        i != e; ++i, ++idx) {
4775     const QualType Ty = i->getType();
4776     const BuiltinType *BT = Ty->getAs<BuiltinType>();
4777 
4778     if (!BT || BT->getKind() != BuiltinType::Double)
4779       continue;
4780 
4781     uint64_t Offset = Layout.getFieldOffset(idx);
4782     if (Offset % 64) // Ignore doubles that are not aligned.
4783       continue;
4784 
4785     // Add ((Offset - LastOffset) / 64) args of type i64.
4786     for (unsigned j = (Offset - LastOffset) / 64; j > 0; --j)
4787       ArgList.push_back(I64);
4788 
4789     // Add double type.
4790     ArgList.push_back(llvm::Type::getDoubleTy(getVMContext()));
4791     LastOffset = Offset + 64;
4792   }
4793 
4794   CoerceToIntArgs(TySize - LastOffset, IntArgList);
4795   ArgList.append(IntArgList.begin(), IntArgList.end());
4796 
4797   return llvm::StructType::get(getVMContext(), ArgList);
4798 }
4799 
4800 llvm::Type *MipsABIInfo::getPaddingType(uint64_t OrigOffset,
4801                                         uint64_t Offset) const {
4802   if (OrigOffset + MinABIStackAlignInBytes > Offset)
4803     return 0;
4804 
4805   return llvm::IntegerType::get(getVMContext(), (Offset - OrigOffset) * 8);
4806 }
4807 
4808 ABIArgInfo
4809 MipsABIInfo::classifyArgumentType(QualType Ty, uint64_t &Offset) const {
4810   uint64_t OrigOffset = Offset;
4811   uint64_t TySize = getContext().getTypeSize(Ty);
4812   uint64_t Align = getContext().getTypeAlign(Ty) / 8;
4813 
4814   Align = std::min(std::max(Align, (uint64_t)MinABIStackAlignInBytes),
4815                    (uint64_t)StackAlignInBytes);
4816   unsigned CurrOffset = llvm::RoundUpToAlignment(Offset, Align);
4817   Offset = CurrOffset + llvm::RoundUpToAlignment(TySize, Align * 8) / 8;
4818 
4819   if (isAggregateTypeForABI(Ty) || Ty->isVectorType()) {
4820     // Ignore empty aggregates.
4821     if (TySize == 0)
4822       return ABIArgInfo::getIgnore();
4823 
4824     if (CGCXXABI::RecordArgABI RAA = getRecordArgABI(Ty, getCXXABI())) {
4825       Offset = OrigOffset + MinABIStackAlignInBytes;
4826       return ABIArgInfo::getIndirect(0, RAA == CGCXXABI::RAA_DirectInMemory);
4827     }
4828 
4829     // If we have reached here, aggregates are passed directly by coercing to
4830     // another structure type. Padding is inserted if the offset of the
4831     // aggregate is unaligned.
4832     return ABIArgInfo::getDirect(HandleAggregates(Ty, TySize), 0,
4833                                  getPaddingType(OrigOffset, CurrOffset));
4834   }
4835 
4836   // Treat an enum type as its underlying type.
4837   if (const EnumType *EnumTy = Ty->getAs<EnumType>())
4838     Ty = EnumTy->getDecl()->getIntegerType();
4839 
4840   if (Ty->isPromotableIntegerType())
4841     return ABIArgInfo::getExtend();
4842 
4843   return ABIArgInfo::getDirect(
4844       0, 0, IsO32 ? 0 : getPaddingType(OrigOffset, CurrOffset));
4845 }
4846 
4847 llvm::Type*
4848 MipsABIInfo::returnAggregateInRegs(QualType RetTy, uint64_t Size) const {
4849   const RecordType *RT = RetTy->getAs<RecordType>();
4850   SmallVector<llvm::Type*, 8> RTList;
4851 
4852   if (RT && RT->isStructureOrClassType()) {
4853     const RecordDecl *RD = RT->getDecl();
4854     const ASTRecordLayout &Layout = getContext().getASTRecordLayout(RD);
4855     unsigned FieldCnt = Layout.getFieldCount();
4856 
4857     // N32/64 returns struct/classes in floating point registers if the
4858     // following conditions are met:
4859     // 1. The size of the struct/class is no larger than 128-bit.
4860     // 2. The struct/class has one or two fields all of which are floating
4861     //    point types.
4862     // 3. The offset of the first field is zero (this follows what gcc does).
4863     //
4864     // Any other composite results are returned in integer registers.
4865     //
4866     if (FieldCnt && (FieldCnt <= 2) && !Layout.getFieldOffset(0)) {
4867       RecordDecl::field_iterator b = RD->field_begin(), e = RD->field_end();
4868       for (; b != e; ++b) {
4869         const BuiltinType *BT = b->getType()->getAs<BuiltinType>();
4870 
4871         if (!BT || !BT->isFloatingPoint())
4872           break;
4873 
4874         RTList.push_back(CGT.ConvertType(b->getType()));
4875       }
4876 
4877       if (b == e)
4878         return llvm::StructType::get(getVMContext(), RTList,
4879                                      RD->hasAttr<PackedAttr>());
4880 
4881       RTList.clear();
4882     }
4883   }
4884 
4885   CoerceToIntArgs(Size, RTList);
4886   return llvm::StructType::get(getVMContext(), RTList);
4887 }
4888 
4889 ABIArgInfo MipsABIInfo::classifyReturnType(QualType RetTy) const {
4890   uint64_t Size = getContext().getTypeSize(RetTy);
4891 
4892   if (RetTy->isVoidType() || Size == 0)
4893     return ABIArgInfo::getIgnore();
4894 
4895   if (isAggregateTypeForABI(RetTy) || RetTy->isVectorType()) {
4896     if (isRecordReturnIndirect(RetTy, getCXXABI()))
4897       return ABIArgInfo::getIndirect(0);
4898 
4899     if (Size <= 128) {
4900       if (RetTy->isAnyComplexType())
4901         return ABIArgInfo::getDirect();
4902 
4903       // O32 returns integer vectors in registers.
4904       if (IsO32 && RetTy->isVectorType() && !RetTy->hasFloatingRepresentation())
4905         return ABIArgInfo::getDirect(returnAggregateInRegs(RetTy, Size));
4906 
4907       if (!IsO32)
4908         return ABIArgInfo::getDirect(returnAggregateInRegs(RetTy, Size));
4909     }
4910 
4911     return ABIArgInfo::getIndirect(0);
4912   }
4913 
4914   // Treat an enum type as its underlying type.
4915   if (const EnumType *EnumTy = RetTy->getAs<EnumType>())
4916     RetTy = EnumTy->getDecl()->getIntegerType();
4917 
4918   return (RetTy->isPromotableIntegerType() ?
4919           ABIArgInfo::getExtend() : ABIArgInfo::getDirect());
4920 }
4921 
4922 void MipsABIInfo::computeInfo(CGFunctionInfo &FI) const {
4923   ABIArgInfo &RetInfo = FI.getReturnInfo();
4924   RetInfo = classifyReturnType(FI.getReturnType());
4925 
4926   // Check if a pointer to an aggregate is passed as a hidden argument.
4927   uint64_t Offset = RetInfo.isIndirect() ? MinABIStackAlignInBytes : 0;
4928 
4929   for (CGFunctionInfo::arg_iterator it = FI.arg_begin(), ie = FI.arg_end();
4930        it != ie; ++it)
4931     it->info = classifyArgumentType(it->type, Offset);
4932 }
4933 
4934 llvm::Value* MipsABIInfo::EmitVAArg(llvm::Value *VAListAddr, QualType Ty,
4935                                     CodeGenFunction &CGF) const {
4936   llvm::Type *BP = CGF.Int8PtrTy;
4937   llvm::Type *BPP = CGF.Int8PtrPtrTy;
4938 
4939   CGBuilderTy &Builder = CGF.Builder;
4940   llvm::Value *VAListAddrAsBPP = Builder.CreateBitCast(VAListAddr, BPP, "ap");
4941   llvm::Value *Addr = Builder.CreateLoad(VAListAddrAsBPP, "ap.cur");
4942   int64_t TypeAlign = getContext().getTypeAlign(Ty) / 8;
4943   llvm::Type *PTy = llvm::PointerType::getUnqual(CGF.ConvertType(Ty));
4944   llvm::Value *AddrTyped;
4945   unsigned PtrWidth = getTarget().getPointerWidth(0);
4946   llvm::IntegerType *IntTy = (PtrWidth == 32) ? CGF.Int32Ty : CGF.Int64Ty;
4947 
4948   if (TypeAlign > MinABIStackAlignInBytes) {
4949     llvm::Value *AddrAsInt = CGF.Builder.CreatePtrToInt(Addr, IntTy);
4950     llvm::Value *Inc = llvm::ConstantInt::get(IntTy, TypeAlign - 1);
4951     llvm::Value *Mask = llvm::ConstantInt::get(IntTy, -TypeAlign);
4952     llvm::Value *Add = CGF.Builder.CreateAdd(AddrAsInt, Inc);
4953     llvm::Value *And = CGF.Builder.CreateAnd(Add, Mask);
4954     AddrTyped = CGF.Builder.CreateIntToPtr(And, PTy);
4955   }
4956   else
4957     AddrTyped = Builder.CreateBitCast(Addr, PTy);
4958 
4959   llvm::Value *AlignedAddr = Builder.CreateBitCast(AddrTyped, BP);
4960   TypeAlign = std::max((unsigned)TypeAlign, MinABIStackAlignInBytes);
4961   uint64_t Offset =
4962     llvm::RoundUpToAlignment(CGF.getContext().getTypeSize(Ty) / 8, TypeAlign);
4963   llvm::Value *NextAddr =
4964     Builder.CreateGEP(AlignedAddr, llvm::ConstantInt::get(IntTy, Offset),
4965                       "ap.next");
4966   Builder.CreateStore(NextAddr, VAListAddrAsBPP);
4967 
4968   return AddrTyped;
4969 }
4970 
4971 bool
4972 MIPSTargetCodeGenInfo::initDwarfEHRegSizeTable(CodeGen::CodeGenFunction &CGF,
4973                                                llvm::Value *Address) const {
4974   // This information comes from gcc's implementation, which seems to
4975   // as canonical as it gets.
4976 
4977   // Everything on MIPS is 4 bytes.  Double-precision FP registers
4978   // are aliased to pairs of single-precision FP registers.
4979   llvm::Value *Four8 = llvm::ConstantInt::get(CGF.Int8Ty, 4);
4980 
4981   // 0-31 are the general purpose registers, $0 - $31.
4982   // 32-63 are the floating-point registers, $f0 - $f31.
4983   // 64 and 65 are the multiply/divide registers, $hi and $lo.
4984   // 66 is the (notional, I think) register for signal-handler return.
4985   AssignToArrayRange(CGF.Builder, Address, Four8, 0, 65);
4986 
4987   // 67-74 are the floating-point status registers, $fcc0 - $fcc7.
4988   // They are one bit wide and ignored here.
4989 
4990   // 80-111 are the coprocessor 0 registers, $c0r0 - $c0r31.
4991   // (coprocessor 1 is the FP unit)
4992   // 112-143 are the coprocessor 2 registers, $c2r0 - $c2r31.
4993   // 144-175 are the coprocessor 3 registers, $c3r0 - $c3r31.
4994   // 176-181 are the DSP accumulator registers.
4995   AssignToArrayRange(CGF.Builder, Address, Four8, 80, 181);
4996   return false;
4997 }
4998 
4999 //===----------------------------------------------------------------------===//
5000 // TCE ABI Implementation (see http://tce.cs.tut.fi). Uses mostly the defaults.
5001 // Currently subclassed only to implement custom OpenCL C function attribute
5002 // handling.
5003 //===----------------------------------------------------------------------===//
5004 
5005 namespace {
5006 
5007 class TCETargetCodeGenInfo : public DefaultTargetCodeGenInfo {
5008 public:
5009   TCETargetCodeGenInfo(CodeGenTypes &CGT)
5010     : DefaultTargetCodeGenInfo(CGT) {}
5011 
5012   virtual void SetTargetAttributes(const Decl *D, llvm::GlobalValue *GV,
5013                                    CodeGen::CodeGenModule &M) const;
5014 };
5015 
5016 void TCETargetCodeGenInfo::SetTargetAttributes(const Decl *D,
5017                                                llvm::GlobalValue *GV,
5018                                                CodeGen::CodeGenModule &M) const {
5019   const FunctionDecl *FD = dyn_cast<FunctionDecl>(D);
5020   if (!FD) return;
5021 
5022   llvm::Function *F = cast<llvm::Function>(GV);
5023 
5024   if (M.getLangOpts().OpenCL) {
5025     if (FD->hasAttr<OpenCLKernelAttr>()) {
5026       // OpenCL C Kernel functions are not subject to inlining
5027       F->addFnAttr(llvm::Attribute::NoInline);
5028       const ReqdWorkGroupSizeAttr *Attr = FD->getAttr<ReqdWorkGroupSizeAttr>();
5029       if (Attr) {
5030         // Convert the reqd_work_group_size() attributes to metadata.
5031         llvm::LLVMContext &Context = F->getContext();
5032         llvm::NamedMDNode *OpenCLMetadata =
5033             M.getModule().getOrInsertNamedMetadata("opencl.kernel_wg_size_info");
5034 
5035         SmallVector<llvm::Value*, 5> Operands;
5036         Operands.push_back(F);
5037 
5038         Operands.push_back(llvm::Constant::getIntegerValue(M.Int32Ty,
5039                              llvm::APInt(32, Attr->getXDim())));
5040         Operands.push_back(llvm::Constant::getIntegerValue(M.Int32Ty,
5041                              llvm::APInt(32, Attr->getYDim())));
5042         Operands.push_back(llvm::Constant::getIntegerValue(M.Int32Ty,
5043                              llvm::APInt(32, Attr->getZDim())));
5044 
5045         // Add a boolean constant operand for "required" (true) or "hint" (false)
5046         // for implementing the work_group_size_hint attr later. Currently
5047         // always true as the hint is not yet implemented.
5048         Operands.push_back(llvm::ConstantInt::getTrue(Context));
5049         OpenCLMetadata->addOperand(llvm::MDNode::get(Context, Operands));
5050       }
5051     }
5052   }
5053 }
5054 
5055 }
5056 
5057 //===----------------------------------------------------------------------===//
5058 // Hexagon ABI Implementation
5059 //===----------------------------------------------------------------------===//
5060 
5061 namespace {
5062 
5063 class HexagonABIInfo : public ABIInfo {
5064 
5065 
5066 public:
5067   HexagonABIInfo(CodeGenTypes &CGT) : ABIInfo(CGT) {}
5068 
5069 private:
5070 
5071   ABIArgInfo classifyReturnType(QualType RetTy) const;
5072   ABIArgInfo classifyArgumentType(QualType RetTy) const;
5073 
5074   virtual void computeInfo(CGFunctionInfo &FI) const;
5075 
5076   virtual llvm::Value *EmitVAArg(llvm::Value *VAListAddr, QualType Ty,
5077                                  CodeGenFunction &CGF) const;
5078 };
5079 
5080 class HexagonTargetCodeGenInfo : public TargetCodeGenInfo {
5081 public:
5082   HexagonTargetCodeGenInfo(CodeGenTypes &CGT)
5083     :TargetCodeGenInfo(new HexagonABIInfo(CGT)) {}
5084 
5085   int getDwarfEHStackPointer(CodeGen::CodeGenModule &M) const {
5086     return 29;
5087   }
5088 };
5089 
5090 }
5091 
5092 void HexagonABIInfo::computeInfo(CGFunctionInfo &FI) const {
5093   FI.getReturnInfo() = classifyReturnType(FI.getReturnType());
5094   for (CGFunctionInfo::arg_iterator it = FI.arg_begin(), ie = FI.arg_end();
5095        it != ie; ++it)
5096     it->info = classifyArgumentType(it->type);
5097 }
5098 
5099 ABIArgInfo HexagonABIInfo::classifyArgumentType(QualType Ty) const {
5100   if (!isAggregateTypeForABI(Ty)) {
5101     // Treat an enum type as its underlying type.
5102     if (const EnumType *EnumTy = Ty->getAs<EnumType>())
5103       Ty = EnumTy->getDecl()->getIntegerType();
5104 
5105     return (Ty->isPromotableIntegerType() ?
5106             ABIArgInfo::getExtend() : ABIArgInfo::getDirect());
5107   }
5108 
5109   // Ignore empty records.
5110   if (isEmptyRecord(getContext(), Ty, true))
5111     return ABIArgInfo::getIgnore();
5112 
5113   if (CGCXXABI::RecordArgABI RAA = getRecordArgABI(Ty, getCXXABI()))
5114     return ABIArgInfo::getIndirect(0, RAA == CGCXXABI::RAA_DirectInMemory);
5115 
5116   uint64_t Size = getContext().getTypeSize(Ty);
5117   if (Size > 64)
5118     return ABIArgInfo::getIndirect(0, /*ByVal=*/true);
5119     // Pass in the smallest viable integer type.
5120   else if (Size > 32)
5121       return ABIArgInfo::getDirect(llvm::Type::getInt64Ty(getVMContext()));
5122   else if (Size > 16)
5123       return ABIArgInfo::getDirect(llvm::Type::getInt32Ty(getVMContext()));
5124   else if (Size > 8)
5125       return ABIArgInfo::getDirect(llvm::Type::getInt16Ty(getVMContext()));
5126   else
5127       return ABIArgInfo::getDirect(llvm::Type::getInt8Ty(getVMContext()));
5128 }
5129 
5130 ABIArgInfo HexagonABIInfo::classifyReturnType(QualType RetTy) const {
5131   if (RetTy->isVoidType())
5132     return ABIArgInfo::getIgnore();
5133 
5134   // Large vector types should be returned via memory.
5135   if (RetTy->isVectorType() && getContext().getTypeSize(RetTy) > 64)
5136     return ABIArgInfo::getIndirect(0);
5137 
5138   if (!isAggregateTypeForABI(RetTy)) {
5139     // Treat an enum type as its underlying type.
5140     if (const EnumType *EnumTy = RetTy->getAs<EnumType>())
5141       RetTy = EnumTy->getDecl()->getIntegerType();
5142 
5143     return (RetTy->isPromotableIntegerType() ?
5144             ABIArgInfo::getExtend() : ABIArgInfo::getDirect());
5145   }
5146 
5147   // Structures with either a non-trivial destructor or a non-trivial
5148   // copy constructor are always indirect.
5149   if (isRecordReturnIndirect(RetTy, getCXXABI()))
5150     return ABIArgInfo::getIndirect(0, /*ByVal=*/false);
5151 
5152   if (isEmptyRecord(getContext(), RetTy, true))
5153     return ABIArgInfo::getIgnore();
5154 
5155   // Aggregates <= 8 bytes are returned in r0; other aggregates
5156   // are returned indirectly.
5157   uint64_t Size = getContext().getTypeSize(RetTy);
5158   if (Size <= 64) {
5159     // Return in the smallest viable integer type.
5160     if (Size <= 8)
5161       return ABIArgInfo::getDirect(llvm::Type::getInt8Ty(getVMContext()));
5162     if (Size <= 16)
5163       return ABIArgInfo::getDirect(llvm::Type::getInt16Ty(getVMContext()));
5164     if (Size <= 32)
5165       return ABIArgInfo::getDirect(llvm::Type::getInt32Ty(getVMContext()));
5166     return ABIArgInfo::getDirect(llvm::Type::getInt64Ty(getVMContext()));
5167   }
5168 
5169   return ABIArgInfo::getIndirect(0, /*ByVal=*/true);
5170 }
5171 
5172 llvm::Value *HexagonABIInfo::EmitVAArg(llvm::Value *VAListAddr, QualType Ty,
5173                                        CodeGenFunction &CGF) const {
5174   // FIXME: Need to handle alignment
5175   llvm::Type *BPP = CGF.Int8PtrPtrTy;
5176 
5177   CGBuilderTy &Builder = CGF.Builder;
5178   llvm::Value *VAListAddrAsBPP = Builder.CreateBitCast(VAListAddr, BPP,
5179                                                        "ap");
5180   llvm::Value *Addr = Builder.CreateLoad(VAListAddrAsBPP, "ap.cur");
5181   llvm::Type *PTy =
5182     llvm::PointerType::getUnqual(CGF.ConvertType(Ty));
5183   llvm::Value *AddrTyped = Builder.CreateBitCast(Addr, PTy);
5184 
5185   uint64_t Offset =
5186     llvm::RoundUpToAlignment(CGF.getContext().getTypeSize(Ty) / 8, 4);
5187   llvm::Value *NextAddr =
5188     Builder.CreateGEP(Addr, llvm::ConstantInt::get(CGF.Int32Ty, Offset),
5189                       "ap.next");
5190   Builder.CreateStore(NextAddr, VAListAddrAsBPP);
5191 
5192   return AddrTyped;
5193 }
5194 
5195 
5196 //===----------------------------------------------------------------------===//
5197 // SPARC v9 ABI Implementation.
5198 // Based on the SPARC Compliance Definition version 2.4.1.
5199 //
5200 // Function arguments a mapped to a nominal "parameter array" and promoted to
5201 // registers depending on their type. Each argument occupies 8 or 16 bytes in
5202 // the array, structs larger than 16 bytes are passed indirectly.
5203 //
5204 // One case requires special care:
5205 //
5206 //   struct mixed {
5207 //     int i;
5208 //     float f;
5209 //   };
5210 //
5211 // When a struct mixed is passed by value, it only occupies 8 bytes in the
5212 // parameter array, but the int is passed in an integer register, and the float
5213 // is passed in a floating point register. This is represented as two arguments
5214 // with the LLVM IR inreg attribute:
5215 //
5216 //   declare void f(i32 inreg %i, float inreg %f)
5217 //
5218 // The code generator will only allocate 4 bytes from the parameter array for
5219 // the inreg arguments. All other arguments are allocated a multiple of 8
5220 // bytes.
5221 //
5222 namespace {
5223 class SparcV9ABIInfo : public ABIInfo {
5224 public:
5225   SparcV9ABIInfo(CodeGenTypes &CGT) : ABIInfo(CGT) {}
5226 
5227 private:
5228   ABIArgInfo classifyType(QualType RetTy, unsigned SizeLimit) const;
5229   virtual void computeInfo(CGFunctionInfo &FI) const;
5230   virtual llvm::Value *EmitVAArg(llvm::Value *VAListAddr, QualType Ty,
5231                                  CodeGenFunction &CGF) const;
5232 
5233   // Coercion type builder for structs passed in registers. The coercion type
5234   // serves two purposes:
5235   //
5236   // 1. Pad structs to a multiple of 64 bits, so they are passed 'left-aligned'
5237   //    in registers.
5238   // 2. Expose aligned floating point elements as first-level elements, so the
5239   //    code generator knows to pass them in floating point registers.
5240   //
5241   // We also compute the InReg flag which indicates that the struct contains
5242   // aligned 32-bit floats.
5243   //
5244   struct CoerceBuilder {
5245     llvm::LLVMContext &Context;
5246     const llvm::DataLayout &DL;
5247     SmallVector<llvm::Type*, 8> Elems;
5248     uint64_t Size;
5249     bool InReg;
5250 
5251     CoerceBuilder(llvm::LLVMContext &c, const llvm::DataLayout &dl)
5252       : Context(c), DL(dl), Size(0), InReg(false) {}
5253 
5254     // Pad Elems with integers until Size is ToSize.
5255     void pad(uint64_t ToSize) {
5256       assert(ToSize >= Size && "Cannot remove elements");
5257       if (ToSize == Size)
5258         return;
5259 
5260       // Finish the current 64-bit word.
5261       uint64_t Aligned = llvm::RoundUpToAlignment(Size, 64);
5262       if (Aligned > Size && Aligned <= ToSize) {
5263         Elems.push_back(llvm::IntegerType::get(Context, Aligned - Size));
5264         Size = Aligned;
5265       }
5266 
5267       // Add whole 64-bit words.
5268       while (Size + 64 <= ToSize) {
5269         Elems.push_back(llvm::Type::getInt64Ty(Context));
5270         Size += 64;
5271       }
5272 
5273       // Final in-word padding.
5274       if (Size < ToSize) {
5275         Elems.push_back(llvm::IntegerType::get(Context, ToSize - Size));
5276         Size = ToSize;
5277       }
5278     }
5279 
5280     // Add a floating point element at Offset.
5281     void addFloat(uint64_t Offset, llvm::Type *Ty, unsigned Bits) {
5282       // Unaligned floats are treated as integers.
5283       if (Offset % Bits)
5284         return;
5285       // The InReg flag is only required if there are any floats < 64 bits.
5286       if (Bits < 64)
5287         InReg = true;
5288       pad(Offset);
5289       Elems.push_back(Ty);
5290       Size = Offset + Bits;
5291     }
5292 
5293     // Add a struct type to the coercion type, starting at Offset (in bits).
5294     void addStruct(uint64_t Offset, llvm::StructType *StrTy) {
5295       const llvm::StructLayout *Layout = DL.getStructLayout(StrTy);
5296       for (unsigned i = 0, e = StrTy->getNumElements(); i != e; ++i) {
5297         llvm::Type *ElemTy = StrTy->getElementType(i);
5298         uint64_t ElemOffset = Offset + Layout->getElementOffsetInBits(i);
5299         switch (ElemTy->getTypeID()) {
5300         case llvm::Type::StructTyID:
5301           addStruct(ElemOffset, cast<llvm::StructType>(ElemTy));
5302           break;
5303         case llvm::Type::FloatTyID:
5304           addFloat(ElemOffset, ElemTy, 32);
5305           break;
5306         case llvm::Type::DoubleTyID:
5307           addFloat(ElemOffset, ElemTy, 64);
5308           break;
5309         case llvm::Type::FP128TyID:
5310           addFloat(ElemOffset, ElemTy, 128);
5311           break;
5312         case llvm::Type::PointerTyID:
5313           if (ElemOffset % 64 == 0) {
5314             pad(ElemOffset);
5315             Elems.push_back(ElemTy);
5316             Size += 64;
5317           }
5318           break;
5319         default:
5320           break;
5321         }
5322       }
5323     }
5324 
5325     // Check if Ty is a usable substitute for the coercion type.
5326     bool isUsableType(llvm::StructType *Ty) const {
5327       if (Ty->getNumElements() != Elems.size())
5328         return false;
5329       for (unsigned i = 0, e = Elems.size(); i != e; ++i)
5330         if (Elems[i] != Ty->getElementType(i))
5331           return false;
5332       return true;
5333     }
5334 
5335     // Get the coercion type as a literal struct type.
5336     llvm::Type *getType() const {
5337       if (Elems.size() == 1)
5338         return Elems.front();
5339       else
5340         return llvm::StructType::get(Context, Elems);
5341     }
5342   };
5343 };
5344 } // end anonymous namespace
5345 
5346 ABIArgInfo
5347 SparcV9ABIInfo::classifyType(QualType Ty, unsigned SizeLimit) const {
5348   if (Ty->isVoidType())
5349     return ABIArgInfo::getIgnore();
5350 
5351   uint64_t Size = getContext().getTypeSize(Ty);
5352 
5353   // Anything too big to fit in registers is passed with an explicit indirect
5354   // pointer / sret pointer.
5355   if (Size > SizeLimit)
5356     return ABIArgInfo::getIndirect(0, /*ByVal=*/false);
5357 
5358   // Treat an enum type as its underlying type.
5359   if (const EnumType *EnumTy = Ty->getAs<EnumType>())
5360     Ty = EnumTy->getDecl()->getIntegerType();
5361 
5362   // Integer types smaller than a register are extended.
5363   if (Size < 64 && Ty->isIntegerType())
5364     return ABIArgInfo::getExtend();
5365 
5366   // Other non-aggregates go in registers.
5367   if (!isAggregateTypeForABI(Ty))
5368     return ABIArgInfo::getDirect();
5369 
5370   // If a C++ object has either a non-trivial copy constructor or a non-trivial
5371   // destructor, it is passed with an explicit indirect pointer / sret pointer.
5372   if (CGCXXABI::RecordArgABI RAA = getRecordArgABI(Ty, getCXXABI()))
5373     return ABIArgInfo::getIndirect(0, RAA == CGCXXABI::RAA_DirectInMemory);
5374 
5375   // This is a small aggregate type that should be passed in registers.
5376   // Build a coercion type from the LLVM struct type.
5377   llvm::StructType *StrTy = dyn_cast<llvm::StructType>(CGT.ConvertType(Ty));
5378   if (!StrTy)
5379     return ABIArgInfo::getDirect();
5380 
5381   CoerceBuilder CB(getVMContext(), getDataLayout());
5382   CB.addStruct(0, StrTy);
5383   CB.pad(llvm::RoundUpToAlignment(CB.DL.getTypeSizeInBits(StrTy), 64));
5384 
5385   // Try to use the original type for coercion.
5386   llvm::Type *CoerceTy = CB.isUsableType(StrTy) ? StrTy : CB.getType();
5387 
5388   if (CB.InReg)
5389     return ABIArgInfo::getDirectInReg(CoerceTy);
5390   else
5391     return ABIArgInfo::getDirect(CoerceTy);
5392 }
5393 
5394 llvm::Value *SparcV9ABIInfo::EmitVAArg(llvm::Value *VAListAddr, QualType Ty,
5395                                        CodeGenFunction &CGF) const {
5396   ABIArgInfo AI = classifyType(Ty, 16 * 8);
5397   llvm::Type *ArgTy = CGT.ConvertType(Ty);
5398   if (AI.canHaveCoerceToType() && !AI.getCoerceToType())
5399     AI.setCoerceToType(ArgTy);
5400 
5401   llvm::Type *BPP = CGF.Int8PtrPtrTy;
5402   CGBuilderTy &Builder = CGF.Builder;
5403   llvm::Value *VAListAddrAsBPP = Builder.CreateBitCast(VAListAddr, BPP, "ap");
5404   llvm::Value *Addr = Builder.CreateLoad(VAListAddrAsBPP, "ap.cur");
5405   llvm::Type *ArgPtrTy = llvm::PointerType::getUnqual(ArgTy);
5406   llvm::Value *ArgAddr;
5407   unsigned Stride;
5408 
5409   switch (AI.getKind()) {
5410   case ABIArgInfo::Expand:
5411     llvm_unreachable("Unsupported ABI kind for va_arg");
5412 
5413   case ABIArgInfo::Extend:
5414     Stride = 8;
5415     ArgAddr = Builder
5416       .CreateConstGEP1_32(Addr, 8 - getDataLayout().getTypeAllocSize(ArgTy),
5417                           "extend");
5418     break;
5419 
5420   case ABIArgInfo::Direct:
5421     Stride = getDataLayout().getTypeAllocSize(AI.getCoerceToType());
5422     ArgAddr = Addr;
5423     break;
5424 
5425   case ABIArgInfo::Indirect:
5426     Stride = 8;
5427     ArgAddr = Builder.CreateBitCast(Addr,
5428                                     llvm::PointerType::getUnqual(ArgPtrTy),
5429                                     "indirect");
5430     ArgAddr = Builder.CreateLoad(ArgAddr, "indirect.arg");
5431     break;
5432 
5433   case ABIArgInfo::Ignore:
5434     return llvm::UndefValue::get(ArgPtrTy);
5435   }
5436 
5437   // Update VAList.
5438   Addr = Builder.CreateConstGEP1_32(Addr, Stride, "ap.next");
5439   Builder.CreateStore(Addr, VAListAddrAsBPP);
5440 
5441   return Builder.CreatePointerCast(ArgAddr, ArgPtrTy, "arg.addr");
5442 }
5443 
5444 void SparcV9ABIInfo::computeInfo(CGFunctionInfo &FI) const {
5445   FI.getReturnInfo() = classifyType(FI.getReturnType(), 32 * 8);
5446   for (CGFunctionInfo::arg_iterator it = FI.arg_begin(), ie = FI.arg_end();
5447        it != ie; ++it)
5448     it->info = classifyType(it->type, 16 * 8);
5449 }
5450 
5451 namespace {
5452 class SparcV9TargetCodeGenInfo : public TargetCodeGenInfo {
5453 public:
5454   SparcV9TargetCodeGenInfo(CodeGenTypes &CGT)
5455     : TargetCodeGenInfo(new SparcV9ABIInfo(CGT)) {}
5456 };
5457 } // end anonymous namespace
5458 
5459 
5460 //===----------------------------------------------------------------------===//
5461 // Xcore ABI Implementation
5462 //===----------------------------------------------------------------------===//
5463 namespace {
5464 class XCoreABIInfo : public DefaultABIInfo {
5465 public:
5466   XCoreABIInfo(CodeGen::CodeGenTypes &CGT) : DefaultABIInfo(CGT) {}
5467   virtual llvm::Value *EmitVAArg(llvm::Value *VAListAddr, QualType Ty,
5468                                  CodeGenFunction &CGF) const;
5469 };
5470 
5471 class XcoreTargetCodeGenInfo : public TargetCodeGenInfo {
5472 public:
5473   XcoreTargetCodeGenInfo(CodeGenTypes &CGT)
5474     :TargetCodeGenInfo(new XCoreABIInfo(CGT)) {}
5475 };
5476 } // End anonymous namespace.
5477 
5478 llvm::Value *XCoreABIInfo::EmitVAArg(llvm::Value *VAListAddr, QualType Ty,
5479                                      CodeGenFunction &CGF) const {
5480   CGBuilderTy &Builder = CGF.Builder;
5481 
5482   // Get the VAList.
5483   llvm::Value *VAListAddrAsBPP = Builder.CreateBitCast(VAListAddr,
5484                                                        CGF.Int8PtrPtrTy);
5485   llvm::Value *AP = Builder.CreateLoad(VAListAddrAsBPP);
5486 
5487   // Handle the argument.
5488   ABIArgInfo AI = classifyArgumentType(Ty);
5489   llvm::Type *ArgTy = CGT.ConvertType(Ty);
5490   if (AI.canHaveCoerceToType() && !AI.getCoerceToType())
5491     AI.setCoerceToType(ArgTy);
5492   llvm::Type *ArgPtrTy = llvm::PointerType::getUnqual(ArgTy);
5493   llvm::Value *Val;
5494   uint64_t ArgSize = 0;
5495   switch (AI.getKind()) {
5496   case ABIArgInfo::Expand:
5497     llvm_unreachable("Unsupported ABI kind for va_arg");
5498   case ABIArgInfo::Ignore:
5499     Val = llvm::UndefValue::get(ArgPtrTy);
5500     ArgSize = 0;
5501     break;
5502   case ABIArgInfo::Extend:
5503   case ABIArgInfo::Direct:
5504     Val = Builder.CreatePointerCast(AP, ArgPtrTy);
5505     ArgSize = getDataLayout().getTypeAllocSize(AI.getCoerceToType());
5506     if (ArgSize < 4)
5507       ArgSize = 4;
5508     break;
5509   case ABIArgInfo::Indirect:
5510     llvm::Value *ArgAddr;
5511     ArgAddr = Builder.CreateBitCast(AP, llvm::PointerType::getUnqual(ArgPtrTy));
5512     ArgAddr = Builder.CreateLoad(ArgAddr);
5513     Val = Builder.CreatePointerCast(ArgAddr, ArgPtrTy);
5514     ArgSize = 4;
5515     break;
5516   }
5517 
5518   // Increment the VAList.
5519   if (ArgSize) {
5520     llvm::Value *APN = Builder.CreateConstGEP1_32(AP, ArgSize);
5521     Builder.CreateStore(APN, VAListAddrAsBPP);
5522   }
5523   return Val;
5524 }
5525 
5526 //===----------------------------------------------------------------------===//
5527 // Driver code
5528 //===----------------------------------------------------------------------===//
5529 
5530 const TargetCodeGenInfo &CodeGenModule::getTargetCodeGenInfo() {
5531   if (TheTargetCodeGenInfo)
5532     return *TheTargetCodeGenInfo;
5533 
5534   const llvm::Triple &Triple = getTarget().getTriple();
5535   switch (Triple.getArch()) {
5536   default:
5537     return *(TheTargetCodeGenInfo = new DefaultTargetCodeGenInfo(Types));
5538 
5539   case llvm::Triple::le32:
5540     return *(TheTargetCodeGenInfo = new PNaClTargetCodeGenInfo(Types));
5541   case llvm::Triple::mips:
5542   case llvm::Triple::mipsel:
5543     return *(TheTargetCodeGenInfo = new MIPSTargetCodeGenInfo(Types, true));
5544 
5545   case llvm::Triple::mips64:
5546   case llvm::Triple::mips64el:
5547     return *(TheTargetCodeGenInfo = new MIPSTargetCodeGenInfo(Types, false));
5548 
5549   case llvm::Triple::aarch64:
5550     return *(TheTargetCodeGenInfo = new AArch64TargetCodeGenInfo(Types));
5551 
5552   case llvm::Triple::arm:
5553   case llvm::Triple::thumb:
5554     {
5555       ARMABIInfo::ABIKind Kind = ARMABIInfo::AAPCS;
5556       if (strcmp(getTarget().getABI(), "apcs-gnu") == 0)
5557         Kind = ARMABIInfo::APCS;
5558       else if (CodeGenOpts.FloatABI == "hard" ||
5559                (CodeGenOpts.FloatABI != "soft" &&
5560                 Triple.getEnvironment() == llvm::Triple::GNUEABIHF))
5561         Kind = ARMABIInfo::AAPCS_VFP;
5562 
5563       switch (Triple.getOS()) {
5564         case llvm::Triple::NaCl:
5565           return *(TheTargetCodeGenInfo =
5566                    new NaClARMTargetCodeGenInfo(Types, Kind));
5567         default:
5568           return *(TheTargetCodeGenInfo =
5569                    new ARMTargetCodeGenInfo(Types, Kind));
5570       }
5571     }
5572 
5573   case llvm::Triple::ppc:
5574     return *(TheTargetCodeGenInfo = new PPC32TargetCodeGenInfo(Types));
5575   case llvm::Triple::ppc64:
5576     if (Triple.isOSBinFormatELF())
5577       return *(TheTargetCodeGenInfo = new PPC64_SVR4_TargetCodeGenInfo(Types));
5578     else
5579       return *(TheTargetCodeGenInfo = new PPC64TargetCodeGenInfo(Types));
5580   case llvm::Triple::ppc64le:
5581     assert(Triple.isOSBinFormatELF() && "PPC64 LE non-ELF not supported!");
5582     return *(TheTargetCodeGenInfo = new PPC64_SVR4_TargetCodeGenInfo(Types));
5583 
5584   case llvm::Triple::nvptx:
5585   case llvm::Triple::nvptx64:
5586     return *(TheTargetCodeGenInfo = new NVPTXTargetCodeGenInfo(Types));
5587 
5588   case llvm::Triple::msp430:
5589     return *(TheTargetCodeGenInfo = new MSP430TargetCodeGenInfo(Types));
5590 
5591   case llvm::Triple::systemz:
5592     return *(TheTargetCodeGenInfo = new SystemZTargetCodeGenInfo(Types));
5593 
5594   case llvm::Triple::tce:
5595     return *(TheTargetCodeGenInfo = new TCETargetCodeGenInfo(Types));
5596 
5597   case llvm::Triple::x86: {
5598     bool IsDarwinVectorABI = Triple.isOSDarwin();
5599     bool IsSmallStructInRegABI =
5600         X86_32TargetCodeGenInfo::isStructReturnInRegABI(Triple, CodeGenOpts);
5601     bool IsWin32FloatStructABI = (Triple.getOS() == llvm::Triple::Win32);
5602 
5603     if (Triple.getOS() == llvm::Triple::Win32) {
5604       return *(TheTargetCodeGenInfo =
5605                new WinX86_32TargetCodeGenInfo(Types,
5606                                               IsDarwinVectorABI, IsSmallStructInRegABI,
5607                                               IsWin32FloatStructABI,
5608                                               CodeGenOpts.NumRegisterParameters));
5609     } else {
5610       return *(TheTargetCodeGenInfo =
5611                new X86_32TargetCodeGenInfo(Types,
5612                                            IsDarwinVectorABI, IsSmallStructInRegABI,
5613                                            IsWin32FloatStructABI,
5614                                            CodeGenOpts.NumRegisterParameters));
5615     }
5616   }
5617 
5618   case llvm::Triple::x86_64: {
5619     bool HasAVX = strcmp(getTarget().getABI(), "avx") == 0;
5620 
5621     switch (Triple.getOS()) {
5622     case llvm::Triple::Win32:
5623     case llvm::Triple::MinGW32:
5624     case llvm::Triple::Cygwin:
5625       return *(TheTargetCodeGenInfo = new WinX86_64TargetCodeGenInfo(Types));
5626     case llvm::Triple::NaCl:
5627       return *(TheTargetCodeGenInfo = new NaClX86_64TargetCodeGenInfo(Types,
5628                                                                       HasAVX));
5629     default:
5630       return *(TheTargetCodeGenInfo = new X86_64TargetCodeGenInfo(Types,
5631                                                                   HasAVX));
5632     }
5633   }
5634   case llvm::Triple::hexagon:
5635     return *(TheTargetCodeGenInfo = new HexagonTargetCodeGenInfo(Types));
5636   case llvm::Triple::sparcv9:
5637     return *(TheTargetCodeGenInfo = new SparcV9TargetCodeGenInfo(Types));
5638   case llvm::Triple::xcore:
5639     return *(TheTargetCodeGenInfo = new XcoreTargetCodeGenInfo(Types));
5640 
5641   }
5642 }
5643