TargetInfo.cpp revision adfa45ffd67d1959cb1ff8cec88ad2ff3ffb7798
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 "CodeGenFunction.h"
18#include "clang/AST/RecordLayout.h"
19#include "clang/Frontend/CodeGenOptions.h"
20#include "llvm/Type.h"
21#include "llvm/Target/TargetData.h"
22#include "llvm/ADT/Triple.h"
23#include "llvm/Support/raw_ostream.h"
24using namespace clang;
25using namespace CodeGen;
26
27static void AssignToArrayRange(CodeGen::CGBuilderTy &Builder,
28                               llvm::Value *Array,
29                               llvm::Value *Value,
30                               unsigned FirstIndex,
31                               unsigned LastIndex) {
32  // Alternatively, we could emit this as a loop in the source.
33  for (unsigned I = FirstIndex; I <= LastIndex; ++I) {
34    llvm::Value *Cell = Builder.CreateConstInBoundsGEP1_32(Array, I);
35    Builder.CreateStore(Value, Cell);
36  }
37}
38
39static bool isAggregateTypeForABI(QualType T) {
40  return CodeGenFunction::hasAggregateLLVMType(T) ||
41         T->isMemberFunctionPointerType();
42}
43
44ABIInfo::~ABIInfo() {}
45
46ASTContext &ABIInfo::getContext() const {
47  return CGT.getContext();
48}
49
50llvm::LLVMContext &ABIInfo::getVMContext() const {
51  return CGT.getLLVMContext();
52}
53
54const llvm::TargetData &ABIInfo::getTargetData() const {
55  return CGT.getTargetData();
56}
57
58
59void ABIArgInfo::dump() const {
60  raw_ostream &OS = llvm::errs();
61  OS << "(ABIArgInfo Kind=";
62  switch (TheKind) {
63  case Direct:
64    OS << "Direct Type=";
65    if (llvm::Type *Ty = getCoerceToType())
66      Ty->print(OS);
67    else
68      OS << "null";
69    break;
70  case Extend:
71    OS << "Extend";
72    break;
73  case Ignore:
74    OS << "Ignore";
75    break;
76  case Indirect:
77    OS << "Indirect Align=" << getIndirectAlign()
78       << " ByVal=" << getIndirectByVal()
79       << " Realign=" << getIndirectRealign();
80    break;
81  case Expand:
82    OS << "Expand";
83    break;
84  }
85  OS << ")\n";
86}
87
88TargetCodeGenInfo::~TargetCodeGenInfo() { delete Info; }
89
90// If someone can figure out a general rule for this, that would be great.
91// It's probably just doomed to be platform-dependent, though.
92unsigned TargetCodeGenInfo::getSizeOfUnwindException() const {
93  // Verified for:
94  //   x86-64     FreeBSD, Linux, Darwin
95  //   x86-32     FreeBSD, Linux, Darwin
96  //   PowerPC    Linux, Darwin
97  //   ARM        Darwin (*not* EABI)
98  return 32;
99}
100
101bool TargetCodeGenInfo::isNoProtoCallVariadic(const CallArgList &args,
102                                     const FunctionNoProtoType *fnType) const {
103  // The following conventions are known to require this to be false:
104  //   x86_stdcall
105  //   MIPS
106  // For everything else, we just prefer false unless we opt out.
107  return false;
108}
109
110static bool isEmptyRecord(ASTContext &Context, QualType T, bool AllowArrays);
111
112/// isEmptyField - Return true iff a the field is "empty", that is it
113/// is an unnamed bit-field or an (array of) empty record(s).
114static bool isEmptyField(ASTContext &Context, const FieldDecl *FD,
115                         bool AllowArrays) {
116  if (FD->isUnnamedBitfield())
117    return true;
118
119  QualType FT = FD->getType();
120
121  // Constant arrays of empty records count as empty, strip them off.
122  // Constant arrays of zero length always count as empty.
123  if (AllowArrays)
124    while (const ConstantArrayType *AT = Context.getAsConstantArrayType(FT)) {
125      if (AT->getSize() == 0)
126        return true;
127      FT = AT->getElementType();
128    }
129
130  const RecordType *RT = FT->getAs<RecordType>();
131  if (!RT)
132    return false;
133
134  // C++ record fields are never empty, at least in the Itanium ABI.
135  //
136  // FIXME: We should use a predicate for whether this behavior is true in the
137  // current ABI.
138  if (isa<CXXRecordDecl>(RT->getDecl()))
139    return false;
140
141  return isEmptyRecord(Context, FT, AllowArrays);
142}
143
144/// isEmptyRecord - Return true iff a structure contains only empty
145/// fields. Note that a structure with a flexible array member is not
146/// considered empty.
147static bool isEmptyRecord(ASTContext &Context, QualType T, bool AllowArrays) {
148  const RecordType *RT = T->getAs<RecordType>();
149  if (!RT)
150    return 0;
151  const RecordDecl *RD = RT->getDecl();
152  if (RD->hasFlexibleArrayMember())
153    return false;
154
155  // If this is a C++ record, check the bases first.
156  if (const CXXRecordDecl *CXXRD = dyn_cast<CXXRecordDecl>(RD))
157    for (CXXRecordDecl::base_class_const_iterator i = CXXRD->bases_begin(),
158           e = CXXRD->bases_end(); i != e; ++i)
159      if (!isEmptyRecord(Context, i->getType(), true))
160        return false;
161
162  for (RecordDecl::field_iterator i = RD->field_begin(), e = RD->field_end();
163         i != e; ++i)
164    if (!isEmptyField(Context, *i, AllowArrays))
165      return false;
166  return true;
167}
168
169/// hasNonTrivialDestructorOrCopyConstructor - Determine if a type has either
170/// a non-trivial destructor or a non-trivial copy constructor.
171static bool hasNonTrivialDestructorOrCopyConstructor(const RecordType *RT) {
172  const CXXRecordDecl *RD = dyn_cast<CXXRecordDecl>(RT->getDecl());
173  if (!RD)
174    return false;
175
176  return !RD->hasTrivialDestructor() || !RD->hasTrivialCopyConstructor();
177}
178
179/// isRecordWithNonTrivialDestructorOrCopyConstructor - Determine if a type is
180/// a record type with either a non-trivial destructor or a non-trivial copy
181/// constructor.
182static bool isRecordWithNonTrivialDestructorOrCopyConstructor(QualType T) {
183  const RecordType *RT = T->getAs<RecordType>();
184  if (!RT)
185    return false;
186
187  return hasNonTrivialDestructorOrCopyConstructor(RT);
188}
189
190/// isSingleElementStruct - Determine if a structure is a "single
191/// element struct", i.e. it has exactly one non-empty field or
192/// exactly one field which is itself a single element
193/// struct. Structures with flexible array members are never
194/// considered single element structs.
195///
196/// \return The field declaration for the single non-empty field, if
197/// it exists.
198static const Type *isSingleElementStruct(QualType T, ASTContext &Context) {
199  const RecordType *RT = T->getAsStructureType();
200  if (!RT)
201    return 0;
202
203  const RecordDecl *RD = RT->getDecl();
204  if (RD->hasFlexibleArrayMember())
205    return 0;
206
207  const Type *Found = 0;
208
209  // If this is a C++ record, check the bases first.
210  if (const CXXRecordDecl *CXXRD = dyn_cast<CXXRecordDecl>(RD)) {
211    for (CXXRecordDecl::base_class_const_iterator i = CXXRD->bases_begin(),
212           e = CXXRD->bases_end(); i != e; ++i) {
213      // Ignore empty records.
214      if (isEmptyRecord(Context, i->getType(), true))
215        continue;
216
217      // If we already found an element then this isn't a single-element struct.
218      if (Found)
219        return 0;
220
221      // If this is non-empty and not a single element struct, the composite
222      // cannot be a single element struct.
223      Found = isSingleElementStruct(i->getType(), Context);
224      if (!Found)
225        return 0;
226    }
227  }
228
229  // Check for single element.
230  for (RecordDecl::field_iterator i = RD->field_begin(), e = RD->field_end();
231         i != e; ++i) {
232    const FieldDecl *FD = *i;
233    QualType FT = FD->getType();
234
235    // Ignore empty fields.
236    if (isEmptyField(Context, FD, true))
237      continue;
238
239    // If we already found an element then this isn't a single-element
240    // struct.
241    if (Found)
242      return 0;
243
244    // Treat single element arrays as the element.
245    while (const ConstantArrayType *AT = Context.getAsConstantArrayType(FT)) {
246      if (AT->getSize().getZExtValue() != 1)
247        break;
248      FT = AT->getElementType();
249    }
250
251    if (!isAggregateTypeForABI(FT)) {
252      Found = FT.getTypePtr();
253    } else {
254      Found = isSingleElementStruct(FT, Context);
255      if (!Found)
256        return 0;
257    }
258  }
259
260  // We don't consider a struct a single-element struct if it has
261  // padding beyond the element type.
262  if (Found && Context.getTypeSize(Found) != Context.getTypeSize(T))
263    return 0;
264
265  return Found;
266}
267
268static bool is32Or64BitBasicType(QualType Ty, ASTContext &Context) {
269  if (!Ty->getAs<BuiltinType>() && !Ty->hasPointerRepresentation() &&
270      !Ty->isAnyComplexType() && !Ty->isEnumeralType() &&
271      !Ty->isBlockPointerType())
272    return false;
273
274  uint64_t Size = Context.getTypeSize(Ty);
275  return Size == 32 || Size == 64;
276}
277
278/// canExpandIndirectArgument - Test whether an argument type which is to be
279/// passed indirectly (on the stack) would have the equivalent layout if it was
280/// expanded into separate arguments. If so, we prefer to do the latter to avoid
281/// inhibiting optimizations.
282///
283// FIXME: This predicate is missing many cases, currently it just follows
284// llvm-gcc (checks that all fields are 32-bit or 64-bit primitive types). We
285// should probably make this smarter, or better yet make the LLVM backend
286// capable of handling it.
287static bool canExpandIndirectArgument(QualType Ty, ASTContext &Context) {
288  // We can only expand structure types.
289  const RecordType *RT = Ty->getAs<RecordType>();
290  if (!RT)
291    return false;
292
293  // We can only expand (C) structures.
294  //
295  // FIXME: This needs to be generalized to handle classes as well.
296  const RecordDecl *RD = RT->getDecl();
297  if (!RD->isStruct() || isa<CXXRecordDecl>(RD))
298    return false;
299
300  uint64_t Size = 0;
301
302  for (RecordDecl::field_iterator i = RD->field_begin(), e = RD->field_end();
303         i != e; ++i) {
304    const FieldDecl *FD = *i;
305
306    if (!is32Or64BitBasicType(FD->getType(), Context))
307      return false;
308
309    // FIXME: Reject bit-fields wholesale; there are two problems, we don't know
310    // how to expand them yet, and the predicate for telling if a bitfield still
311    // counts as "basic" is more complicated than what we were doing previously.
312    if (FD->isBitField())
313      return false;
314
315    Size += Context.getTypeSize(FD->getType());
316  }
317
318  // Make sure there are not any holes in the struct.
319  if (Size != Context.getTypeSize(Ty))
320    return false;
321
322  return true;
323}
324
325namespace {
326/// DefaultABIInfo - The default implementation for ABI specific
327/// details. This implementation provides information which results in
328/// self-consistent and sensible LLVM IR generation, but does not
329/// conform to any particular ABI.
330class DefaultABIInfo : public ABIInfo {
331public:
332  DefaultABIInfo(CodeGen::CodeGenTypes &CGT) : ABIInfo(CGT) {}
333
334  ABIArgInfo classifyReturnType(QualType RetTy) const;
335  ABIArgInfo classifyArgumentType(QualType RetTy) const;
336
337  virtual void computeInfo(CGFunctionInfo &FI) const {
338    FI.getReturnInfo() = classifyReturnType(FI.getReturnType());
339    for (CGFunctionInfo::arg_iterator it = FI.arg_begin(), ie = FI.arg_end();
340         it != ie; ++it)
341      it->info = classifyArgumentType(it->type);
342  }
343
344  virtual llvm::Value *EmitVAArg(llvm::Value *VAListAddr, QualType Ty,
345                                 CodeGenFunction &CGF) const;
346};
347
348class DefaultTargetCodeGenInfo : public TargetCodeGenInfo {
349public:
350  DefaultTargetCodeGenInfo(CodeGen::CodeGenTypes &CGT)
351    : TargetCodeGenInfo(new DefaultABIInfo(CGT)) {}
352};
353
354llvm::Value *DefaultABIInfo::EmitVAArg(llvm::Value *VAListAddr, QualType Ty,
355                                       CodeGenFunction &CGF) const {
356  return 0;
357}
358
359ABIArgInfo DefaultABIInfo::classifyArgumentType(QualType Ty) const {
360  if (isAggregateTypeForABI(Ty)) {
361    // Records with non trivial destructors/constructors should not be passed
362    // by value.
363    if (isRecordWithNonTrivialDestructorOrCopyConstructor(Ty))
364      return ABIArgInfo::getIndirect(0, /*ByVal=*/false);
365
366    return ABIArgInfo::getIndirect(0);
367  }
368
369  // Treat an enum type as its underlying type.
370  if (const EnumType *EnumTy = Ty->getAs<EnumType>())
371    Ty = EnumTy->getDecl()->getIntegerType();
372
373  return (Ty->isPromotableIntegerType() ?
374          ABIArgInfo::getExtend() : ABIArgInfo::getDirect());
375}
376
377ABIArgInfo DefaultABIInfo::classifyReturnType(QualType RetTy) const {
378  if (RetTy->isVoidType())
379    return ABIArgInfo::getIgnore();
380
381  if (isAggregateTypeForABI(RetTy))
382    return ABIArgInfo::getIndirect(0);
383
384  // Treat an enum type as its underlying type.
385  if (const EnumType *EnumTy = RetTy->getAs<EnumType>())
386    RetTy = EnumTy->getDecl()->getIntegerType();
387
388  return (RetTy->isPromotableIntegerType() ?
389          ABIArgInfo::getExtend() : ABIArgInfo::getDirect());
390}
391
392/// UseX86_MMXType - Return true if this is an MMX type that should use the
393/// special x86_mmx type.
394bool UseX86_MMXType(llvm::Type *IRType) {
395  // If the type is an MMX type <2 x i32>, <4 x i16>, or <8 x i8>, use the
396  // special x86_mmx type.
397  return IRType->isVectorTy() && IRType->getPrimitiveSizeInBits() == 64 &&
398    cast<llvm::VectorType>(IRType)->getElementType()->isIntegerTy() &&
399    IRType->getScalarSizeInBits() != 64;
400}
401
402static llvm::Type* X86AdjustInlineAsmType(CodeGen::CodeGenFunction &CGF,
403                                          StringRef Constraint,
404                                          llvm::Type* Ty) {
405  if ((Constraint == "y" || Constraint == "&y") && Ty->isVectorTy())
406    return llvm::Type::getX86_MMXTy(CGF.getLLVMContext());
407  return Ty;
408}
409
410//===----------------------------------------------------------------------===//
411// X86-32 ABI Implementation
412//===----------------------------------------------------------------------===//
413
414/// X86_32ABIInfo - The X86-32 ABI information.
415class X86_32ABIInfo : public ABIInfo {
416  static const unsigned MinABIStackAlignInBytes = 4;
417
418  bool IsDarwinVectorABI;
419  bool IsSmallStructInRegABI;
420  bool IsMMXDisabled;
421  bool IsWin32FloatStructABI;
422
423  static bool isRegisterSize(unsigned Size) {
424    return (Size == 8 || Size == 16 || Size == 32 || Size == 64);
425  }
426
427  static bool shouldReturnTypeInRegister(QualType Ty, ASTContext &Context,
428                                          unsigned callingConvention);
429
430  /// getIndirectResult - Give a source type \arg Ty, return a suitable result
431  /// such that the argument will be passed in memory.
432  ABIArgInfo getIndirectResult(QualType Ty, bool ByVal = true) const;
433
434  /// \brief Return the alignment to use for the given type on the stack.
435  unsigned getTypeStackAlignInBytes(QualType Ty, unsigned Align) const;
436
437public:
438
439  ABIArgInfo classifyReturnType(QualType RetTy,
440                                unsigned callingConvention) const;
441  ABIArgInfo classifyArgumentType(QualType RetTy) const;
442
443  virtual void computeInfo(CGFunctionInfo &FI) const {
444    FI.getReturnInfo() = classifyReturnType(FI.getReturnType(),
445                                            FI.getCallingConvention());
446    for (CGFunctionInfo::arg_iterator it = FI.arg_begin(), ie = FI.arg_end();
447         it != ie; ++it)
448      it->info = classifyArgumentType(it->type);
449  }
450
451  virtual llvm::Value *EmitVAArg(llvm::Value *VAListAddr, QualType Ty,
452                                 CodeGenFunction &CGF) const;
453
454  X86_32ABIInfo(CodeGen::CodeGenTypes &CGT, bool d, bool p, bool m, bool w)
455    : ABIInfo(CGT), IsDarwinVectorABI(d), IsSmallStructInRegABI(p),
456      IsMMXDisabled(m), IsWin32FloatStructABI(w) {}
457};
458
459class X86_32TargetCodeGenInfo : public TargetCodeGenInfo {
460public:
461  X86_32TargetCodeGenInfo(CodeGen::CodeGenTypes &CGT,
462      bool d, bool p, bool m, bool w)
463    :TargetCodeGenInfo(new X86_32ABIInfo(CGT, d, p, m, w)) {}
464
465  void SetTargetAttributes(const Decl *D, llvm::GlobalValue *GV,
466                           CodeGen::CodeGenModule &CGM) const;
467
468  int getDwarfEHStackPointer(CodeGen::CodeGenModule &CGM) const {
469    // Darwin uses different dwarf register numbers for EH.
470    if (CGM.isTargetDarwin()) return 5;
471
472    return 4;
473  }
474
475  bool initDwarfEHRegSizeTable(CodeGen::CodeGenFunction &CGF,
476                               llvm::Value *Address) const;
477
478  llvm::Type* adjustInlineAsmType(CodeGen::CodeGenFunction &CGF,
479                                  StringRef Constraint,
480                                  llvm::Type* Ty) const {
481    return X86AdjustInlineAsmType(CGF, Constraint, Ty);
482  }
483
484};
485
486}
487
488/// shouldReturnTypeInRegister - Determine if the given type should be
489/// passed in a register (for the Darwin ABI).
490bool X86_32ABIInfo::shouldReturnTypeInRegister(QualType Ty,
491                                               ASTContext &Context,
492                                               unsigned callingConvention) {
493  uint64_t Size = Context.getTypeSize(Ty);
494
495  // Type must be register sized.
496  if (!isRegisterSize(Size))
497    return false;
498
499  if (Ty->isVectorType()) {
500    // 64- and 128- bit vectors inside structures are not returned in
501    // registers.
502    if (Size == 64 || Size == 128)
503      return false;
504
505    return true;
506  }
507
508  // If this is a builtin, pointer, enum, complex type, member pointer, or
509  // member function pointer it is ok.
510  if (Ty->getAs<BuiltinType>() || Ty->hasPointerRepresentation() ||
511      Ty->isAnyComplexType() || Ty->isEnumeralType() ||
512      Ty->isBlockPointerType() || Ty->isMemberPointerType())
513    return true;
514
515  // Arrays are treated like records.
516  if (const ConstantArrayType *AT = Context.getAsConstantArrayType(Ty))
517    return shouldReturnTypeInRegister(AT->getElementType(), Context,
518                                      callingConvention);
519
520  // Otherwise, it must be a record type.
521  const RecordType *RT = Ty->getAs<RecordType>();
522  if (!RT) return false;
523
524  // FIXME: Traverse bases here too.
525
526  // For thiscall conventions, structures will never be returned in
527  // a register.  This is for compatibility with the MSVC ABI
528  if (callingConvention == llvm::CallingConv::X86_ThisCall &&
529      RT->isStructureType()) {
530    return false;
531  }
532
533  // Structure types are passed in register if all fields would be
534  // passed in a register.
535  for (RecordDecl::field_iterator i = RT->getDecl()->field_begin(),
536         e = RT->getDecl()->field_end(); i != e; ++i) {
537    const FieldDecl *FD = *i;
538
539    // Empty fields are ignored.
540    if (isEmptyField(Context, FD, true))
541      continue;
542
543    // Check fields recursively.
544    if (!shouldReturnTypeInRegister(FD->getType(), Context,
545                                    callingConvention))
546      return false;
547  }
548  return true;
549}
550
551ABIArgInfo X86_32ABIInfo::classifyReturnType(QualType RetTy,
552                                            unsigned callingConvention) const {
553  if (RetTy->isVoidType())
554    return ABIArgInfo::getIgnore();
555
556  if (const VectorType *VT = RetTy->getAs<VectorType>()) {
557    // On Darwin, some vectors are returned in registers.
558    if (IsDarwinVectorABI) {
559      uint64_t Size = getContext().getTypeSize(RetTy);
560
561      // 128-bit vectors are a special case; they are returned in
562      // registers and we need to make sure to pick a type the LLVM
563      // backend will like.
564      if (Size == 128)
565        return ABIArgInfo::getDirect(llvm::VectorType::get(
566                  llvm::Type::getInt64Ty(getVMContext()), 2));
567
568      // Always return in register if it fits in a general purpose
569      // register, or if it is 64 bits and has a single element.
570      if ((Size == 8 || Size == 16 || Size == 32) ||
571          (Size == 64 && VT->getNumElements() == 1))
572        return ABIArgInfo::getDirect(llvm::IntegerType::get(getVMContext(),
573                                                            Size));
574
575      return ABIArgInfo::getIndirect(0);
576    }
577
578    return ABIArgInfo::getDirect();
579  }
580
581  if (isAggregateTypeForABI(RetTy)) {
582    if (const RecordType *RT = RetTy->getAs<RecordType>()) {
583      // Structures with either a non-trivial destructor or a non-trivial
584      // copy constructor are always indirect.
585      if (hasNonTrivialDestructorOrCopyConstructor(RT))
586        return ABIArgInfo::getIndirect(0, /*ByVal=*/false);
587
588      // Structures with flexible arrays are always indirect.
589      if (RT->getDecl()->hasFlexibleArrayMember())
590        return ABIArgInfo::getIndirect(0);
591    }
592
593    // If specified, structs and unions are always indirect.
594    if (!IsSmallStructInRegABI && !RetTy->isAnyComplexType())
595      return ABIArgInfo::getIndirect(0);
596
597    // Small structures which are register sized are generally returned
598    // in a register.
599    if (X86_32ABIInfo::shouldReturnTypeInRegister(RetTy, getContext(),
600                                                  callingConvention)) {
601      uint64_t Size = getContext().getTypeSize(RetTy);
602
603      // As a special-case, if the struct is a "single-element" struct, and
604      // the field is of type "float" or "double", return it in a
605      // floating-point register. (MSVC does not apply this special case.)
606      // We apply a similar transformation for pointer types to improve the
607      // quality of the generated IR.
608      if (const Type *SeltTy = isSingleElementStruct(RetTy, getContext()))
609        if ((!IsWin32FloatStructABI && SeltTy->isRealFloatingType())
610            || SeltTy->hasPointerRepresentation())
611          return ABIArgInfo::getDirect(CGT.ConvertType(QualType(SeltTy, 0)));
612
613      // FIXME: We should be able to narrow this integer in cases with dead
614      // padding.
615      return ABIArgInfo::getDirect(llvm::IntegerType::get(getVMContext(),Size));
616    }
617
618    return ABIArgInfo::getIndirect(0);
619  }
620
621  // Treat an enum type as its underlying type.
622  if (const EnumType *EnumTy = RetTy->getAs<EnumType>())
623    RetTy = EnumTy->getDecl()->getIntegerType();
624
625  return (RetTy->isPromotableIntegerType() ?
626          ABIArgInfo::getExtend() : ABIArgInfo::getDirect());
627}
628
629static bool isSSEVectorType(ASTContext &Context, QualType Ty) {
630  return Ty->getAs<VectorType>() && Context.getTypeSize(Ty) == 128;
631}
632
633static bool isRecordWithSSEVectorType(ASTContext &Context, QualType Ty) {
634  const RecordType *RT = Ty->getAs<RecordType>();
635  if (!RT)
636    return 0;
637  const RecordDecl *RD = RT->getDecl();
638
639  // If this is a C++ record, check the bases first.
640  if (const CXXRecordDecl *CXXRD = dyn_cast<CXXRecordDecl>(RD))
641    for (CXXRecordDecl::base_class_const_iterator i = CXXRD->bases_begin(),
642           e = CXXRD->bases_end(); i != e; ++i)
643      if (!isRecordWithSSEVectorType(Context, i->getType()))
644        return false;
645
646  for (RecordDecl::field_iterator i = RD->field_begin(), e = RD->field_end();
647       i != e; ++i) {
648    QualType FT = i->getType();
649
650    if (isSSEVectorType(Context, FT))
651      return true;
652
653    if (isRecordWithSSEVectorType(Context, FT))
654      return true;
655  }
656
657  return false;
658}
659
660unsigned X86_32ABIInfo::getTypeStackAlignInBytes(QualType Ty,
661                                                 unsigned Align) const {
662  // Otherwise, if the alignment is less than or equal to the minimum ABI
663  // alignment, just use the default; the backend will handle this.
664  if (Align <= MinABIStackAlignInBytes)
665    return 0; // Use default alignment.
666
667  // On non-Darwin, the stack type alignment is always 4.
668  if (!IsDarwinVectorABI) {
669    // Set explicit alignment, since we may need to realign the top.
670    return MinABIStackAlignInBytes;
671  }
672
673  // Otherwise, if the type contains an SSE vector type, the alignment is 16.
674  if (Align >= 16 && (isSSEVectorType(getContext(), Ty) ||
675                      isRecordWithSSEVectorType(getContext(), Ty)))
676    return 16;
677
678  return MinABIStackAlignInBytes;
679}
680
681ABIArgInfo X86_32ABIInfo::getIndirectResult(QualType Ty, bool ByVal) const {
682  if (!ByVal)
683    return ABIArgInfo::getIndirect(0, false);
684
685  // Compute the byval alignment.
686  unsigned TypeAlign = getContext().getTypeAlign(Ty) / 8;
687  unsigned StackAlign = getTypeStackAlignInBytes(Ty, TypeAlign);
688  if (StackAlign == 0)
689    return ABIArgInfo::getIndirect(4);
690
691  // If the stack alignment is less than the type alignment, realign the
692  // argument.
693  if (StackAlign < TypeAlign)
694    return ABIArgInfo::getIndirect(StackAlign, /*ByVal=*/true,
695                                   /*Realign=*/true);
696
697  return ABIArgInfo::getIndirect(StackAlign);
698}
699
700ABIArgInfo X86_32ABIInfo::classifyArgumentType(QualType Ty) const {
701  // FIXME: Set alignment on indirect arguments.
702  if (isAggregateTypeForABI(Ty)) {
703    // Structures with flexible arrays are always indirect.
704    if (const RecordType *RT = Ty->getAs<RecordType>()) {
705      // Structures with either a non-trivial destructor or a non-trivial
706      // copy constructor are always indirect.
707      if (hasNonTrivialDestructorOrCopyConstructor(RT))
708        return getIndirectResult(Ty, /*ByVal=*/false);
709
710      if (RT->getDecl()->hasFlexibleArrayMember())
711        return getIndirectResult(Ty);
712    }
713
714    // Ignore empty structs/unions.
715    if (isEmptyRecord(getContext(), Ty, true))
716      return ABIArgInfo::getIgnore();
717
718    // Expand small (<= 128-bit) record types when we know that the stack layout
719    // of those arguments will match the struct. This is important because the
720    // LLVM backend isn't smart enough to remove byval, which inhibits many
721    // optimizations.
722    if (getContext().getTypeSize(Ty) <= 4*32 &&
723        canExpandIndirectArgument(Ty, getContext()))
724      return ABIArgInfo::getExpand();
725
726    return getIndirectResult(Ty);
727  }
728
729  if (const VectorType *VT = Ty->getAs<VectorType>()) {
730    // On Darwin, some vectors are passed in memory, we handle this by passing
731    // it as an i8/i16/i32/i64.
732    if (IsDarwinVectorABI) {
733      uint64_t Size = getContext().getTypeSize(Ty);
734      if ((Size == 8 || Size == 16 || Size == 32) ||
735          (Size == 64 && VT->getNumElements() == 1))
736        return ABIArgInfo::getDirect(llvm::IntegerType::get(getVMContext(),
737                                                            Size));
738    }
739
740    llvm::Type *IRType = CGT.ConvertType(Ty);
741    if (UseX86_MMXType(IRType)) {
742      if (IsMMXDisabled)
743        return ABIArgInfo::getDirect(llvm::IntegerType::get(getVMContext(),
744                                                            64));
745      ABIArgInfo AAI = ABIArgInfo::getDirect(IRType);
746      AAI.setCoerceToType(llvm::Type::getX86_MMXTy(getVMContext()));
747      return AAI;
748    }
749
750    return ABIArgInfo::getDirect();
751  }
752
753
754  if (const EnumType *EnumTy = Ty->getAs<EnumType>())
755    Ty = EnumTy->getDecl()->getIntegerType();
756
757  return (Ty->isPromotableIntegerType() ?
758          ABIArgInfo::getExtend() : ABIArgInfo::getDirect());
759}
760
761llvm::Value *X86_32ABIInfo::EmitVAArg(llvm::Value *VAListAddr, QualType Ty,
762                                      CodeGenFunction &CGF) const {
763  llvm::Type *BPP = CGF.Int8PtrPtrTy;
764
765  CGBuilderTy &Builder = CGF.Builder;
766  llvm::Value *VAListAddrAsBPP = Builder.CreateBitCast(VAListAddr, BPP,
767                                                       "ap");
768  llvm::Value *Addr = Builder.CreateLoad(VAListAddrAsBPP, "ap.cur");
769
770  // Compute if the address needs to be aligned
771  unsigned Align = CGF.getContext().getTypeAlignInChars(Ty).getQuantity();
772  Align = getTypeStackAlignInBytes(Ty, Align);
773  Align = std::max(Align, 4U);
774  if (Align > 4) {
775    // addr = (addr + align - 1) & -align;
776    llvm::Value *Offset =
777      llvm::ConstantInt::get(CGF.Int32Ty, Align - 1);
778    Addr = CGF.Builder.CreateGEP(Addr, Offset);
779    llvm::Value *AsInt = CGF.Builder.CreatePtrToInt(Addr,
780                                                    CGF.Int32Ty);
781    llvm::Value *Mask = llvm::ConstantInt::get(CGF.Int32Ty, -Align);
782    Addr = CGF.Builder.CreateIntToPtr(CGF.Builder.CreateAnd(AsInt, Mask),
783                                      Addr->getType(),
784                                      "ap.cur.aligned");
785  }
786
787  llvm::Type *PTy =
788    llvm::PointerType::getUnqual(CGF.ConvertType(Ty));
789  llvm::Value *AddrTyped = Builder.CreateBitCast(Addr, PTy);
790
791  uint64_t Offset =
792    llvm::RoundUpToAlignment(CGF.getContext().getTypeSize(Ty) / 8, Align);
793  llvm::Value *NextAddr =
794    Builder.CreateGEP(Addr, llvm::ConstantInt::get(CGF.Int32Ty, Offset),
795                      "ap.next");
796  Builder.CreateStore(NextAddr, VAListAddrAsBPP);
797
798  return AddrTyped;
799}
800
801void X86_32TargetCodeGenInfo::SetTargetAttributes(const Decl *D,
802                                                  llvm::GlobalValue *GV,
803                                            CodeGen::CodeGenModule &CGM) const {
804  if (const FunctionDecl *FD = dyn_cast<FunctionDecl>(D)) {
805    if (FD->hasAttr<X86ForceAlignArgPointerAttr>()) {
806      // Get the LLVM function.
807      llvm::Function *Fn = cast<llvm::Function>(GV);
808
809      // Now add the 'alignstack' attribute with a value of 16.
810      Fn->addFnAttr(llvm::Attribute::constructStackAlignmentFromInt(16));
811    }
812  }
813}
814
815bool X86_32TargetCodeGenInfo::initDwarfEHRegSizeTable(
816                                               CodeGen::CodeGenFunction &CGF,
817                                               llvm::Value *Address) const {
818  CodeGen::CGBuilderTy &Builder = CGF.Builder;
819
820  llvm::Value *Four8 = llvm::ConstantInt::get(CGF.Int8Ty, 4);
821
822  // 0-7 are the eight integer registers;  the order is different
823  //   on Darwin (for EH), but the range is the same.
824  // 8 is %eip.
825  AssignToArrayRange(Builder, Address, Four8, 0, 8);
826
827  if (CGF.CGM.isTargetDarwin()) {
828    // 12-16 are st(0..4).  Not sure why we stop at 4.
829    // These have size 16, which is sizeof(long double) on
830    // platforms with 8-byte alignment for that type.
831    llvm::Value *Sixteen8 = llvm::ConstantInt::get(CGF.Int8Ty, 16);
832    AssignToArrayRange(Builder, Address, Sixteen8, 12, 16);
833
834  } else {
835    // 9 is %eflags, which doesn't get a size on Darwin for some
836    // reason.
837    Builder.CreateStore(Four8, Builder.CreateConstInBoundsGEP1_32(Address, 9));
838
839    // 11-16 are st(0..5).  Not sure why we stop at 5.
840    // These have size 12, which is sizeof(long double) on
841    // platforms with 4-byte alignment for that type.
842    llvm::Value *Twelve8 = llvm::ConstantInt::get(CGF.Int8Ty, 12);
843    AssignToArrayRange(Builder, Address, Twelve8, 11, 16);
844  }
845
846  return false;
847}
848
849//===----------------------------------------------------------------------===//
850// X86-64 ABI Implementation
851//===----------------------------------------------------------------------===//
852
853
854namespace {
855/// X86_64ABIInfo - The X86_64 ABI information.
856class X86_64ABIInfo : public ABIInfo {
857  enum Class {
858    Integer = 0,
859    SSE,
860    SSEUp,
861    X87,
862    X87Up,
863    ComplexX87,
864    NoClass,
865    Memory
866  };
867
868  /// merge - Implement the X86_64 ABI merging algorithm.
869  ///
870  /// Merge an accumulating classification \arg Accum with a field
871  /// classification \arg Field.
872  ///
873  /// \param Accum - The accumulating classification. This should
874  /// always be either NoClass or the result of a previous merge
875  /// call. In addition, this should never be Memory (the caller
876  /// should just return Memory for the aggregate).
877  static Class merge(Class Accum, Class Field);
878
879  /// postMerge - Implement the X86_64 ABI post merging algorithm.
880  ///
881  /// Post merger cleanup, reduces a malformed Hi and Lo pair to
882  /// final MEMORY or SSE classes when necessary.
883  ///
884  /// \param AggregateSize - The size of the current aggregate in
885  /// the classification process.
886  ///
887  /// \param Lo - The classification for the parts of the type
888  /// residing in the low word of the containing object.
889  ///
890  /// \param Hi - The classification for the parts of the type
891  /// residing in the higher words of the containing object.
892  ///
893  void postMerge(unsigned AggregateSize, Class &Lo, Class &Hi) const;
894
895  /// classify - Determine the x86_64 register classes in which the
896  /// given type T should be passed.
897  ///
898  /// \param Lo - The classification for the parts of the type
899  /// residing in the low word of the containing object.
900  ///
901  /// \param Hi - The classification for the parts of the type
902  /// residing in the high word of the containing object.
903  ///
904  /// \param OffsetBase - The bit offset of this type in the
905  /// containing object.  Some parameters are classified different
906  /// depending on whether they straddle an eightbyte boundary.
907  ///
908  /// If a word is unused its result will be NoClass; if a type should
909  /// be passed in Memory then at least the classification of \arg Lo
910  /// will be Memory.
911  ///
912  /// The \arg Lo class will be NoClass iff the argument is ignored.
913  ///
914  /// If the \arg Lo class is ComplexX87, then the \arg Hi class will
915  /// also be ComplexX87.
916  void classify(QualType T, uint64_t OffsetBase, Class &Lo, Class &Hi) const;
917
918  llvm::Type *GetByteVectorType(QualType Ty) const;
919  llvm::Type *GetSSETypeAtOffset(llvm::Type *IRType,
920                                 unsigned IROffset, QualType SourceTy,
921                                 unsigned SourceOffset) const;
922  llvm::Type *GetINTEGERTypeAtOffset(llvm::Type *IRType,
923                                     unsigned IROffset, QualType SourceTy,
924                                     unsigned SourceOffset) const;
925
926  /// getIndirectResult - Give a source type \arg Ty, return a suitable result
927  /// such that the argument will be returned in memory.
928  ABIArgInfo getIndirectReturnResult(QualType Ty) const;
929
930  /// getIndirectResult - Give a source type \arg Ty, return a suitable result
931  /// such that the argument will be passed in memory.
932  ///
933  /// \param freeIntRegs - The number of free integer registers remaining
934  /// available.
935  ABIArgInfo getIndirectResult(QualType Ty, unsigned freeIntRegs) const;
936
937  ABIArgInfo classifyReturnType(QualType RetTy) const;
938
939  ABIArgInfo classifyArgumentType(QualType Ty,
940                                  unsigned freeIntRegs,
941                                  unsigned &neededInt,
942                                  unsigned &neededSSE) const;
943
944  bool IsIllegalVectorType(QualType Ty) const;
945
946  /// The 0.98 ABI revision clarified a lot of ambiguities,
947  /// unfortunately in ways that were not always consistent with
948  /// certain previous compilers.  In particular, platforms which
949  /// required strict binary compatibility with older versions of GCC
950  /// may need to exempt themselves.
951  bool honorsRevision0_98() const {
952    return !getContext().getTargetInfo().getTriple().isOSDarwin();
953  }
954
955  bool HasAVX;
956
957public:
958  X86_64ABIInfo(CodeGen::CodeGenTypes &CGT, bool hasavx) :
959      ABIInfo(CGT), HasAVX(hasavx) {}
960
961  bool isPassedUsingAVXType(QualType type) const {
962    unsigned neededInt, neededSSE;
963    // The freeIntRegs argument doesn't matter here.
964    ABIArgInfo info = classifyArgumentType(type, 0, neededInt, neededSSE);
965    if (info.isDirect()) {
966      llvm::Type *ty = info.getCoerceToType();
967      if (llvm::VectorType *vectorTy = dyn_cast_or_null<llvm::VectorType>(ty))
968        return (vectorTy->getBitWidth() > 128);
969    }
970    return false;
971  }
972
973  virtual void computeInfo(CGFunctionInfo &FI) const;
974
975  virtual llvm::Value *EmitVAArg(llvm::Value *VAListAddr, QualType Ty,
976                                 CodeGenFunction &CGF) const;
977};
978
979/// WinX86_64ABIInfo - The Windows X86_64 ABI information.
980class WinX86_64ABIInfo : public ABIInfo {
981
982  ABIArgInfo classify(QualType Ty) const;
983
984public:
985  WinX86_64ABIInfo(CodeGen::CodeGenTypes &CGT) : ABIInfo(CGT) {}
986
987  virtual void computeInfo(CGFunctionInfo &FI) const;
988
989  virtual llvm::Value *EmitVAArg(llvm::Value *VAListAddr, QualType Ty,
990                                 CodeGenFunction &CGF) const;
991};
992
993class X86_64TargetCodeGenInfo : public TargetCodeGenInfo {
994public:
995  X86_64TargetCodeGenInfo(CodeGen::CodeGenTypes &CGT, bool HasAVX)
996    : TargetCodeGenInfo(new X86_64ABIInfo(CGT, HasAVX)) {}
997
998  const X86_64ABIInfo &getABIInfo() const {
999    return static_cast<const X86_64ABIInfo&>(TargetCodeGenInfo::getABIInfo());
1000  }
1001
1002  int getDwarfEHStackPointer(CodeGen::CodeGenModule &CGM) const {
1003    return 7;
1004  }
1005
1006  bool initDwarfEHRegSizeTable(CodeGen::CodeGenFunction &CGF,
1007                               llvm::Value *Address) const {
1008    llvm::Value *Eight8 = llvm::ConstantInt::get(CGF.Int8Ty, 8);
1009
1010    // 0-15 are the 16 integer registers.
1011    // 16 is %rip.
1012    AssignToArrayRange(CGF.Builder, Address, Eight8, 0, 16);
1013    return false;
1014  }
1015
1016  llvm::Type* adjustInlineAsmType(CodeGen::CodeGenFunction &CGF,
1017                                  StringRef Constraint,
1018                                  llvm::Type* Ty) const {
1019    return X86AdjustInlineAsmType(CGF, Constraint, Ty);
1020  }
1021
1022  bool isNoProtoCallVariadic(const CallArgList &args,
1023                             const FunctionNoProtoType *fnType) const {
1024    // The default CC on x86-64 sets %al to the number of SSA
1025    // registers used, and GCC sets this when calling an unprototyped
1026    // function, so we override the default behavior.  However, don't do
1027    // that when AVX types are involved: the ABI explicitly states it is
1028    // undefined, and it doesn't work in practice because of how the ABI
1029    // defines varargs anyway.
1030    if (fnType->getCallConv() == CC_Default || fnType->getCallConv() == CC_C) {
1031      bool HasAVXType = false;
1032      for (CallArgList::const_iterator
1033             it = args.begin(), ie = args.end(); it != ie; ++it) {
1034        if (getABIInfo().isPassedUsingAVXType(it->Ty)) {
1035          HasAVXType = true;
1036          break;
1037        }
1038      }
1039
1040      if (!HasAVXType)
1041        return true;
1042    }
1043
1044    return TargetCodeGenInfo::isNoProtoCallVariadic(args, fnType);
1045  }
1046
1047};
1048
1049class WinX86_64TargetCodeGenInfo : public TargetCodeGenInfo {
1050public:
1051  WinX86_64TargetCodeGenInfo(CodeGen::CodeGenTypes &CGT)
1052    : TargetCodeGenInfo(new WinX86_64ABIInfo(CGT)) {}
1053
1054  int getDwarfEHStackPointer(CodeGen::CodeGenModule &CGM) const {
1055    return 7;
1056  }
1057
1058  bool initDwarfEHRegSizeTable(CodeGen::CodeGenFunction &CGF,
1059                               llvm::Value *Address) const {
1060    llvm::Value *Eight8 = llvm::ConstantInt::get(CGF.Int8Ty, 8);
1061
1062    // 0-15 are the 16 integer registers.
1063    // 16 is %rip.
1064    AssignToArrayRange(CGF.Builder, Address, Eight8, 0, 16);
1065    return false;
1066  }
1067};
1068
1069}
1070
1071void X86_64ABIInfo::postMerge(unsigned AggregateSize, Class &Lo,
1072                              Class &Hi) const {
1073  // AMD64-ABI 3.2.3p2: Rule 5. Then a post merger cleanup is done:
1074  //
1075  // (a) If one of the classes is Memory, the whole argument is passed in
1076  //     memory.
1077  //
1078  // (b) If X87UP is not preceded by X87, the whole argument is passed in
1079  //     memory.
1080  //
1081  // (c) If the size of the aggregate exceeds two eightbytes and the first
1082  //     eightbyte isn't SSE or any other eightbyte isn't SSEUP, the whole
1083  //     argument is passed in memory. NOTE: This is necessary to keep the
1084  //     ABI working for processors that don't support the __m256 type.
1085  //
1086  // (d) If SSEUP is not preceded by SSE or SSEUP, it is converted to SSE.
1087  //
1088  // Some of these are enforced by the merging logic.  Others can arise
1089  // only with unions; for example:
1090  //   union { _Complex double; unsigned; }
1091  //
1092  // Note that clauses (b) and (c) were added in 0.98.
1093  //
1094  if (Hi == Memory)
1095    Lo = Memory;
1096  if (Hi == X87Up && Lo != X87 && honorsRevision0_98())
1097    Lo = Memory;
1098  if (AggregateSize > 128 && (Lo != SSE || Hi != SSEUp))
1099    Lo = Memory;
1100  if (Hi == SSEUp && Lo != SSE)
1101    Hi = SSE;
1102}
1103
1104X86_64ABIInfo::Class X86_64ABIInfo::merge(Class Accum, Class Field) {
1105  // AMD64-ABI 3.2.3p2: Rule 4. Each field of an object is
1106  // classified recursively so that always two fields are
1107  // considered. The resulting class is calculated according to
1108  // the classes of the fields in the eightbyte:
1109  //
1110  // (a) If both classes are equal, this is the resulting class.
1111  //
1112  // (b) If one of the classes is NO_CLASS, the resulting class is
1113  // the other class.
1114  //
1115  // (c) If one of the classes is MEMORY, the result is the MEMORY
1116  // class.
1117  //
1118  // (d) If one of the classes is INTEGER, the result is the
1119  // INTEGER.
1120  //
1121  // (e) If one of the classes is X87, X87UP, COMPLEX_X87 class,
1122  // MEMORY is used as class.
1123  //
1124  // (f) Otherwise class SSE is used.
1125
1126  // Accum should never be memory (we should have returned) or
1127  // ComplexX87 (because this cannot be passed in a structure).
1128  assert((Accum != Memory && Accum != ComplexX87) &&
1129         "Invalid accumulated classification during merge.");
1130  if (Accum == Field || Field == NoClass)
1131    return Accum;
1132  if (Field == Memory)
1133    return Memory;
1134  if (Accum == NoClass)
1135    return Field;
1136  if (Accum == Integer || Field == Integer)
1137    return Integer;
1138  if (Field == X87 || Field == X87Up || Field == ComplexX87 ||
1139      Accum == X87 || Accum == X87Up)
1140    return Memory;
1141  return SSE;
1142}
1143
1144void X86_64ABIInfo::classify(QualType Ty, uint64_t OffsetBase,
1145                             Class &Lo, Class &Hi) const {
1146  // FIXME: This code can be simplified by introducing a simple value class for
1147  // Class pairs with appropriate constructor methods for the various
1148  // situations.
1149
1150  // FIXME: Some of the split computations are wrong; unaligned vectors
1151  // shouldn't be passed in registers for example, so there is no chance they
1152  // can straddle an eightbyte. Verify & simplify.
1153
1154  Lo = Hi = NoClass;
1155
1156  Class &Current = OffsetBase < 64 ? Lo : Hi;
1157  Current = Memory;
1158
1159  if (const BuiltinType *BT = Ty->getAs<BuiltinType>()) {
1160    BuiltinType::Kind k = BT->getKind();
1161
1162    if (k == BuiltinType::Void) {
1163      Current = NoClass;
1164    } else if (k == BuiltinType::Int128 || k == BuiltinType::UInt128) {
1165      Lo = Integer;
1166      Hi = Integer;
1167    } else if (k >= BuiltinType::Bool && k <= BuiltinType::LongLong) {
1168      Current = Integer;
1169    } else if (k == BuiltinType::Float || k == BuiltinType::Double) {
1170      Current = SSE;
1171    } else if (k == BuiltinType::LongDouble) {
1172      Lo = X87;
1173      Hi = X87Up;
1174    }
1175    // FIXME: _Decimal32 and _Decimal64 are SSE.
1176    // FIXME: _float128 and _Decimal128 are (SSE, SSEUp).
1177    return;
1178  }
1179
1180  if (const EnumType *ET = Ty->getAs<EnumType>()) {
1181    // Classify the underlying integer type.
1182    classify(ET->getDecl()->getIntegerType(), OffsetBase, Lo, Hi);
1183    return;
1184  }
1185
1186  if (Ty->hasPointerRepresentation()) {
1187    Current = Integer;
1188    return;
1189  }
1190
1191  if (Ty->isMemberPointerType()) {
1192    if (Ty->isMemberFunctionPointerType())
1193      Lo = Hi = Integer;
1194    else
1195      Current = Integer;
1196    return;
1197  }
1198
1199  if (const VectorType *VT = Ty->getAs<VectorType>()) {
1200    uint64_t Size = getContext().getTypeSize(VT);
1201    if (Size == 32) {
1202      // gcc passes all <4 x char>, <2 x short>, <1 x int>, <1 x
1203      // float> as integer.
1204      Current = Integer;
1205
1206      // If this type crosses an eightbyte boundary, it should be
1207      // split.
1208      uint64_t EB_Real = (OffsetBase) / 64;
1209      uint64_t EB_Imag = (OffsetBase + Size - 1) / 64;
1210      if (EB_Real != EB_Imag)
1211        Hi = Lo;
1212    } else if (Size == 64) {
1213      // gcc passes <1 x double> in memory. :(
1214      if (VT->getElementType()->isSpecificBuiltinType(BuiltinType::Double))
1215        return;
1216
1217      // gcc passes <1 x long long> as INTEGER.
1218      if (VT->getElementType()->isSpecificBuiltinType(BuiltinType::LongLong) ||
1219          VT->getElementType()->isSpecificBuiltinType(BuiltinType::ULongLong) ||
1220          VT->getElementType()->isSpecificBuiltinType(BuiltinType::Long) ||
1221          VT->getElementType()->isSpecificBuiltinType(BuiltinType::ULong))
1222        Current = Integer;
1223      else
1224        Current = SSE;
1225
1226      // If this type crosses an eightbyte boundary, it should be
1227      // split.
1228      if (OffsetBase && OffsetBase != 64)
1229        Hi = Lo;
1230    } else if (Size == 128 || (HasAVX && Size == 256)) {
1231      // Arguments of 256-bits are split into four eightbyte chunks. The
1232      // least significant one belongs to class SSE and all the others to class
1233      // SSEUP. The original Lo and Hi design considers that types can't be
1234      // greater than 128-bits, so a 64-bit split in Hi and Lo makes sense.
1235      // This design isn't correct for 256-bits, but since there're no cases
1236      // where the upper parts would need to be inspected, avoid adding
1237      // complexity and just consider Hi to match the 64-256 part.
1238      Lo = SSE;
1239      Hi = SSEUp;
1240    }
1241    return;
1242  }
1243
1244  if (const ComplexType *CT = Ty->getAs<ComplexType>()) {
1245    QualType ET = getContext().getCanonicalType(CT->getElementType());
1246
1247    uint64_t Size = getContext().getTypeSize(Ty);
1248    if (ET->isIntegralOrEnumerationType()) {
1249      if (Size <= 64)
1250        Current = Integer;
1251      else if (Size <= 128)
1252        Lo = Hi = Integer;
1253    } else if (ET == getContext().FloatTy)
1254      Current = SSE;
1255    else if (ET == getContext().DoubleTy)
1256      Lo = Hi = SSE;
1257    else if (ET == getContext().LongDoubleTy)
1258      Current = ComplexX87;
1259
1260    // If this complex type crosses an eightbyte boundary then it
1261    // should be split.
1262    uint64_t EB_Real = (OffsetBase) / 64;
1263    uint64_t EB_Imag = (OffsetBase + getContext().getTypeSize(ET)) / 64;
1264    if (Hi == NoClass && EB_Real != EB_Imag)
1265      Hi = Lo;
1266
1267    return;
1268  }
1269
1270  if (const ConstantArrayType *AT = getContext().getAsConstantArrayType(Ty)) {
1271    // Arrays are treated like structures.
1272
1273    uint64_t Size = getContext().getTypeSize(Ty);
1274
1275    // AMD64-ABI 3.2.3p2: Rule 1. If the size of an object is larger
1276    // than four eightbytes, ..., it has class MEMORY.
1277    if (Size > 256)
1278      return;
1279
1280    // AMD64-ABI 3.2.3p2: Rule 1. If ..., or it contains unaligned
1281    // fields, it has class MEMORY.
1282    //
1283    // Only need to check alignment of array base.
1284    if (OffsetBase % getContext().getTypeAlign(AT->getElementType()))
1285      return;
1286
1287    // Otherwise implement simplified merge. We could be smarter about
1288    // this, but it isn't worth it and would be harder to verify.
1289    Current = NoClass;
1290    uint64_t EltSize = getContext().getTypeSize(AT->getElementType());
1291    uint64_t ArraySize = AT->getSize().getZExtValue();
1292
1293    // The only case a 256-bit wide vector could be used is when the array
1294    // contains a single 256-bit element. Since Lo and Hi logic isn't extended
1295    // to work for sizes wider than 128, early check and fallback to memory.
1296    if (Size > 128 && EltSize != 256)
1297      return;
1298
1299    for (uint64_t i=0, Offset=OffsetBase; i<ArraySize; ++i, Offset += EltSize) {
1300      Class FieldLo, FieldHi;
1301      classify(AT->getElementType(), Offset, FieldLo, FieldHi);
1302      Lo = merge(Lo, FieldLo);
1303      Hi = merge(Hi, FieldHi);
1304      if (Lo == Memory || Hi == Memory)
1305        break;
1306    }
1307
1308    postMerge(Size, Lo, Hi);
1309    assert((Hi != SSEUp || Lo == SSE) && "Invalid SSEUp array classification.");
1310    return;
1311  }
1312
1313  if (const RecordType *RT = Ty->getAs<RecordType>()) {
1314    uint64_t Size = getContext().getTypeSize(Ty);
1315
1316    // AMD64-ABI 3.2.3p2: Rule 1. If the size of an object is larger
1317    // than four eightbytes, ..., it has class MEMORY.
1318    if (Size > 256)
1319      return;
1320
1321    // AMD64-ABI 3.2.3p2: Rule 2. If a C++ object has either a non-trivial
1322    // copy constructor or a non-trivial destructor, it is passed by invisible
1323    // reference.
1324    if (hasNonTrivialDestructorOrCopyConstructor(RT))
1325      return;
1326
1327    const RecordDecl *RD = RT->getDecl();
1328
1329    // Assume variable sized types are passed in memory.
1330    if (RD->hasFlexibleArrayMember())
1331      return;
1332
1333    const ASTRecordLayout &Layout = getContext().getASTRecordLayout(RD);
1334
1335    // Reset Lo class, this will be recomputed.
1336    Current = NoClass;
1337
1338    // If this is a C++ record, classify the bases first.
1339    if (const CXXRecordDecl *CXXRD = dyn_cast<CXXRecordDecl>(RD)) {
1340      for (CXXRecordDecl::base_class_const_iterator i = CXXRD->bases_begin(),
1341             e = CXXRD->bases_end(); i != e; ++i) {
1342        assert(!i->isVirtual() && !i->getType()->isDependentType() &&
1343               "Unexpected base class!");
1344        const CXXRecordDecl *Base =
1345          cast<CXXRecordDecl>(i->getType()->getAs<RecordType>()->getDecl());
1346
1347        // Classify this field.
1348        //
1349        // AMD64-ABI 3.2.3p2: Rule 3. If the size of the aggregate exceeds a
1350        // single eightbyte, each is classified separately. Each eightbyte gets
1351        // initialized to class NO_CLASS.
1352        Class FieldLo, FieldHi;
1353        uint64_t Offset =
1354          OffsetBase + getContext().toBits(Layout.getBaseClassOffset(Base));
1355        classify(i->getType(), Offset, FieldLo, FieldHi);
1356        Lo = merge(Lo, FieldLo);
1357        Hi = merge(Hi, FieldHi);
1358        if (Lo == Memory || Hi == Memory)
1359          break;
1360      }
1361    }
1362
1363    // Classify the fields one at a time, merging the results.
1364    unsigned idx = 0;
1365    for (RecordDecl::field_iterator i = RD->field_begin(), e = RD->field_end();
1366           i != e; ++i, ++idx) {
1367      uint64_t Offset = OffsetBase + Layout.getFieldOffset(idx);
1368      bool BitField = i->isBitField();
1369
1370      // AMD64-ABI 3.2.3p2: Rule 1. If the size of an object is larger than
1371      // four eightbytes, or it contains unaligned fields, it has class MEMORY.
1372      //
1373      // The only case a 256-bit wide vector could be used is when the struct
1374      // contains a single 256-bit element. Since Lo and Hi logic isn't extended
1375      // to work for sizes wider than 128, early check and fallback to memory.
1376      //
1377      if (Size > 128 && getContext().getTypeSize(i->getType()) != 256) {
1378        Lo = Memory;
1379        return;
1380      }
1381      // Note, skip this test for bit-fields, see below.
1382      if (!BitField && Offset % getContext().getTypeAlign(i->getType())) {
1383        Lo = Memory;
1384        return;
1385      }
1386
1387      // Classify this field.
1388      //
1389      // AMD64-ABI 3.2.3p2: Rule 3. If the size of the aggregate
1390      // exceeds a single eightbyte, each is classified
1391      // separately. Each eightbyte gets initialized to class
1392      // NO_CLASS.
1393      Class FieldLo, FieldHi;
1394
1395      // Bit-fields require special handling, they do not force the
1396      // structure to be passed in memory even if unaligned, and
1397      // therefore they can straddle an eightbyte.
1398      if (BitField) {
1399        // Ignore padding bit-fields.
1400        if (i->isUnnamedBitfield())
1401          continue;
1402
1403        uint64_t Offset = OffsetBase + Layout.getFieldOffset(idx);
1404        uint64_t Size = i->getBitWidthValue(getContext());
1405
1406        uint64_t EB_Lo = Offset / 64;
1407        uint64_t EB_Hi = (Offset + Size - 1) / 64;
1408        FieldLo = FieldHi = NoClass;
1409        if (EB_Lo) {
1410          assert(EB_Hi == EB_Lo && "Invalid classification, type > 16 bytes.");
1411          FieldLo = NoClass;
1412          FieldHi = Integer;
1413        } else {
1414          FieldLo = Integer;
1415          FieldHi = EB_Hi ? Integer : NoClass;
1416        }
1417      } else
1418        classify(i->getType(), Offset, FieldLo, FieldHi);
1419      Lo = merge(Lo, FieldLo);
1420      Hi = merge(Hi, FieldHi);
1421      if (Lo == Memory || Hi == Memory)
1422        break;
1423    }
1424
1425    postMerge(Size, Lo, Hi);
1426  }
1427}
1428
1429ABIArgInfo X86_64ABIInfo::getIndirectReturnResult(QualType Ty) const {
1430  // If this is a scalar LLVM value then assume LLVM will pass it in the right
1431  // place naturally.
1432  if (!isAggregateTypeForABI(Ty)) {
1433    // Treat an enum type as its underlying type.
1434    if (const EnumType *EnumTy = Ty->getAs<EnumType>())
1435      Ty = EnumTy->getDecl()->getIntegerType();
1436
1437    return (Ty->isPromotableIntegerType() ?
1438            ABIArgInfo::getExtend() : ABIArgInfo::getDirect());
1439  }
1440
1441  return ABIArgInfo::getIndirect(0);
1442}
1443
1444bool X86_64ABIInfo::IsIllegalVectorType(QualType Ty) const {
1445  if (const VectorType *VecTy = Ty->getAs<VectorType>()) {
1446    uint64_t Size = getContext().getTypeSize(VecTy);
1447    unsigned LargestVector = HasAVX ? 256 : 128;
1448    if (Size <= 64 || Size > LargestVector)
1449      return true;
1450  }
1451
1452  return false;
1453}
1454
1455ABIArgInfo X86_64ABIInfo::getIndirectResult(QualType Ty,
1456                                            unsigned freeIntRegs) const {
1457  // If this is a scalar LLVM value then assume LLVM will pass it in the right
1458  // place naturally.
1459  //
1460  // This assumption is optimistic, as there could be free registers available
1461  // when we need to pass this argument in memory, and LLVM could try to pass
1462  // the argument in the free register. This does not seem to happen currently,
1463  // but this code would be much safer if we could mark the argument with
1464  // 'onstack'. See PR12193.
1465  if (!isAggregateTypeForABI(Ty) && !IsIllegalVectorType(Ty)) {
1466    // Treat an enum type as its underlying type.
1467    if (const EnumType *EnumTy = Ty->getAs<EnumType>())
1468      Ty = EnumTy->getDecl()->getIntegerType();
1469
1470    return (Ty->isPromotableIntegerType() ?
1471            ABIArgInfo::getExtend() : ABIArgInfo::getDirect());
1472  }
1473
1474  if (isRecordWithNonTrivialDestructorOrCopyConstructor(Ty))
1475    return ABIArgInfo::getIndirect(0, /*ByVal=*/false);
1476
1477  // Compute the byval alignment. We specify the alignment of the byval in all
1478  // cases so that the mid-level optimizer knows the alignment of the byval.
1479  unsigned Align = std::max(getContext().getTypeAlign(Ty) / 8, 8U);
1480
1481  // Attempt to avoid passing indirect results using byval when possible. This
1482  // is important for good codegen.
1483  //
1484  // We do this by coercing the value into a scalar type which the backend can
1485  // handle naturally (i.e., without using byval).
1486  //
1487  // For simplicity, we currently only do this when we have exhausted all of the
1488  // free integer registers. Doing this when there are free integer registers
1489  // would require more care, as we would have to ensure that the coerced value
1490  // did not claim the unused register. That would require either reording the
1491  // arguments to the function (so that any subsequent inreg values came first),
1492  // or only doing this optimization when there were no following arguments that
1493  // might be inreg.
1494  //
1495  // We currently expect it to be rare (particularly in well written code) for
1496  // arguments to be passed on the stack when there are still free integer
1497  // registers available (this would typically imply large structs being passed
1498  // by value), so this seems like a fair tradeoff for now.
1499  //
1500  // We can revisit this if the backend grows support for 'onstack' parameter
1501  // attributes. See PR12193.
1502  if (freeIntRegs == 0) {
1503    uint64_t Size = getContext().getTypeSize(Ty);
1504
1505    // If this type fits in an eightbyte, coerce it into the matching integral
1506    // type, which will end up on the stack (with alignment 8).
1507    if (Align == 8 && Size <= 64)
1508      return ABIArgInfo::getDirect(llvm::IntegerType::get(getVMContext(),
1509                                                          Size));
1510  }
1511
1512  return ABIArgInfo::getIndirect(Align);
1513}
1514
1515/// GetByteVectorType - The ABI specifies that a value should be passed in an
1516/// full vector XMM/YMM register.  Pick an LLVM IR type that will be passed as a
1517/// vector register.
1518llvm::Type *X86_64ABIInfo::GetByteVectorType(QualType Ty) const {
1519  llvm::Type *IRType = CGT.ConvertType(Ty);
1520
1521  // Wrapper structs that just contain vectors are passed just like vectors,
1522  // strip them off if present.
1523  llvm::StructType *STy = dyn_cast<llvm::StructType>(IRType);
1524  while (STy && STy->getNumElements() == 1) {
1525    IRType = STy->getElementType(0);
1526    STy = dyn_cast<llvm::StructType>(IRType);
1527  }
1528
1529  // If the preferred type is a 16-byte vector, prefer to pass it.
1530  if (llvm::VectorType *VT = dyn_cast<llvm::VectorType>(IRType)){
1531    llvm::Type *EltTy = VT->getElementType();
1532    unsigned BitWidth = VT->getBitWidth();
1533    if ((BitWidth >= 128 && BitWidth <= 256) &&
1534        (EltTy->isFloatTy() || EltTy->isDoubleTy() ||
1535         EltTy->isIntegerTy(8) || EltTy->isIntegerTy(16) ||
1536         EltTy->isIntegerTy(32) || EltTy->isIntegerTy(64) ||
1537         EltTy->isIntegerTy(128)))
1538      return VT;
1539  }
1540
1541  return llvm::VectorType::get(llvm::Type::getDoubleTy(getVMContext()), 2);
1542}
1543
1544/// BitsContainNoUserData - Return true if the specified [start,end) bit range
1545/// is known to either be off the end of the specified type or being in
1546/// alignment padding.  The user type specified is known to be at most 128 bits
1547/// in size, and have passed through X86_64ABIInfo::classify with a successful
1548/// classification that put one of the two halves in the INTEGER class.
1549///
1550/// It is conservatively correct to return false.
1551static bool BitsContainNoUserData(QualType Ty, unsigned StartBit,
1552                                  unsigned EndBit, ASTContext &Context) {
1553  // If the bytes being queried are off the end of the type, there is no user
1554  // data hiding here.  This handles analysis of builtins, vectors and other
1555  // types that don't contain interesting padding.
1556  unsigned TySize = (unsigned)Context.getTypeSize(Ty);
1557  if (TySize <= StartBit)
1558    return true;
1559
1560  if (const ConstantArrayType *AT = Context.getAsConstantArrayType(Ty)) {
1561    unsigned EltSize = (unsigned)Context.getTypeSize(AT->getElementType());
1562    unsigned NumElts = (unsigned)AT->getSize().getZExtValue();
1563
1564    // Check each element to see if the element overlaps with the queried range.
1565    for (unsigned i = 0; i != NumElts; ++i) {
1566      // If the element is after the span we care about, then we're done..
1567      unsigned EltOffset = i*EltSize;
1568      if (EltOffset >= EndBit) break;
1569
1570      unsigned EltStart = EltOffset < StartBit ? StartBit-EltOffset :0;
1571      if (!BitsContainNoUserData(AT->getElementType(), EltStart,
1572                                 EndBit-EltOffset, Context))
1573        return false;
1574    }
1575    // If it overlaps no elements, then it is safe to process as padding.
1576    return true;
1577  }
1578
1579  if (const RecordType *RT = Ty->getAs<RecordType>()) {
1580    const RecordDecl *RD = RT->getDecl();
1581    const ASTRecordLayout &Layout = Context.getASTRecordLayout(RD);
1582
1583    // If this is a C++ record, check the bases first.
1584    if (const CXXRecordDecl *CXXRD = dyn_cast<CXXRecordDecl>(RD)) {
1585      for (CXXRecordDecl::base_class_const_iterator i = CXXRD->bases_begin(),
1586           e = CXXRD->bases_end(); i != e; ++i) {
1587        assert(!i->isVirtual() && !i->getType()->isDependentType() &&
1588               "Unexpected base class!");
1589        const CXXRecordDecl *Base =
1590          cast<CXXRecordDecl>(i->getType()->getAs<RecordType>()->getDecl());
1591
1592        // If the base is after the span we care about, ignore it.
1593        unsigned BaseOffset = Context.toBits(Layout.getBaseClassOffset(Base));
1594        if (BaseOffset >= EndBit) continue;
1595
1596        unsigned BaseStart = BaseOffset < StartBit ? StartBit-BaseOffset :0;
1597        if (!BitsContainNoUserData(i->getType(), BaseStart,
1598                                   EndBit-BaseOffset, Context))
1599          return false;
1600      }
1601    }
1602
1603    // Verify that no field has data that overlaps the region of interest.  Yes
1604    // this could be sped up a lot by being smarter about queried fields,
1605    // however we're only looking at structs up to 16 bytes, so we don't care
1606    // much.
1607    unsigned idx = 0;
1608    for (RecordDecl::field_iterator i = RD->field_begin(), e = RD->field_end();
1609         i != e; ++i, ++idx) {
1610      unsigned FieldOffset = (unsigned)Layout.getFieldOffset(idx);
1611
1612      // If we found a field after the region we care about, then we're done.
1613      if (FieldOffset >= EndBit) break;
1614
1615      unsigned FieldStart = FieldOffset < StartBit ? StartBit-FieldOffset :0;
1616      if (!BitsContainNoUserData(i->getType(), FieldStart, EndBit-FieldOffset,
1617                                 Context))
1618        return false;
1619    }
1620
1621    // If nothing in this record overlapped the area of interest, then we're
1622    // clean.
1623    return true;
1624  }
1625
1626  return false;
1627}
1628
1629/// ContainsFloatAtOffset - Return true if the specified LLVM IR type has a
1630/// float member at the specified offset.  For example, {int,{float}} has a
1631/// float at offset 4.  It is conservatively correct for this routine to return
1632/// false.
1633static bool ContainsFloatAtOffset(llvm::Type *IRType, unsigned IROffset,
1634                                  const llvm::TargetData &TD) {
1635  // Base case if we find a float.
1636  if (IROffset == 0 && IRType->isFloatTy())
1637    return true;
1638
1639  // If this is a struct, recurse into the field at the specified offset.
1640  if (llvm::StructType *STy = dyn_cast<llvm::StructType>(IRType)) {
1641    const llvm::StructLayout *SL = TD.getStructLayout(STy);
1642    unsigned Elt = SL->getElementContainingOffset(IROffset);
1643    IROffset -= SL->getElementOffset(Elt);
1644    return ContainsFloatAtOffset(STy->getElementType(Elt), IROffset, TD);
1645  }
1646
1647  // If this is an array, recurse into the field at the specified offset.
1648  if (llvm::ArrayType *ATy = dyn_cast<llvm::ArrayType>(IRType)) {
1649    llvm::Type *EltTy = ATy->getElementType();
1650    unsigned EltSize = TD.getTypeAllocSize(EltTy);
1651    IROffset -= IROffset/EltSize*EltSize;
1652    return ContainsFloatAtOffset(EltTy, IROffset, TD);
1653  }
1654
1655  return false;
1656}
1657
1658
1659/// GetSSETypeAtOffset - Return a type that will be passed by the backend in the
1660/// low 8 bytes of an XMM register, corresponding to the SSE class.
1661llvm::Type *X86_64ABIInfo::
1662GetSSETypeAtOffset(llvm::Type *IRType, unsigned IROffset,
1663                   QualType SourceTy, unsigned SourceOffset) const {
1664  // The only three choices we have are either double, <2 x float>, or float. We
1665  // pass as float if the last 4 bytes is just padding.  This happens for
1666  // structs that contain 3 floats.
1667  if (BitsContainNoUserData(SourceTy, SourceOffset*8+32,
1668                            SourceOffset*8+64, getContext()))
1669    return llvm::Type::getFloatTy(getVMContext());
1670
1671  // We want to pass as <2 x float> if the LLVM IR type contains a float at
1672  // offset+0 and offset+4.  Walk the LLVM IR type to find out if this is the
1673  // case.
1674  if (ContainsFloatAtOffset(IRType, IROffset, getTargetData()) &&
1675      ContainsFloatAtOffset(IRType, IROffset+4, getTargetData()))
1676    return llvm::VectorType::get(llvm::Type::getFloatTy(getVMContext()), 2);
1677
1678  return llvm::Type::getDoubleTy(getVMContext());
1679}
1680
1681
1682/// GetINTEGERTypeAtOffset - The ABI specifies that a value should be passed in
1683/// an 8-byte GPR.  This means that we either have a scalar or we are talking
1684/// about the high or low part of an up-to-16-byte struct.  This routine picks
1685/// the best LLVM IR type to represent this, which may be i64 or may be anything
1686/// else that the backend will pass in a GPR that works better (e.g. i8, %foo*,
1687/// etc).
1688///
1689/// PrefType is an LLVM IR type that corresponds to (part of) the IR type for
1690/// the source type.  IROffset is an offset in bytes into the LLVM IR type that
1691/// the 8-byte value references.  PrefType may be null.
1692///
1693/// SourceTy is the source level type for the entire argument.  SourceOffset is
1694/// an offset into this that we're processing (which is always either 0 or 8).
1695///
1696llvm::Type *X86_64ABIInfo::
1697GetINTEGERTypeAtOffset(llvm::Type *IRType, unsigned IROffset,
1698                       QualType SourceTy, unsigned SourceOffset) const {
1699  // If we're dealing with an un-offset LLVM IR type, then it means that we're
1700  // returning an 8-byte unit starting with it.  See if we can safely use it.
1701  if (IROffset == 0) {
1702    // Pointers and int64's always fill the 8-byte unit.
1703    if (isa<llvm::PointerType>(IRType) || IRType->isIntegerTy(64))
1704      return IRType;
1705
1706    // If we have a 1/2/4-byte integer, we can use it only if the rest of the
1707    // goodness in the source type is just tail padding.  This is allowed to
1708    // kick in for struct {double,int} on the int, but not on
1709    // struct{double,int,int} because we wouldn't return the second int.  We
1710    // have to do this analysis on the source type because we can't depend on
1711    // unions being lowered a specific way etc.
1712    if (IRType->isIntegerTy(8) || IRType->isIntegerTy(16) ||
1713        IRType->isIntegerTy(32)) {
1714      unsigned BitWidth = cast<llvm::IntegerType>(IRType)->getBitWidth();
1715
1716      if (BitsContainNoUserData(SourceTy, SourceOffset*8+BitWidth,
1717                                SourceOffset*8+64, getContext()))
1718        return IRType;
1719    }
1720  }
1721
1722  if (llvm::StructType *STy = dyn_cast<llvm::StructType>(IRType)) {
1723    // If this is a struct, recurse into the field at the specified offset.
1724    const llvm::StructLayout *SL = getTargetData().getStructLayout(STy);
1725    if (IROffset < SL->getSizeInBytes()) {
1726      unsigned FieldIdx = SL->getElementContainingOffset(IROffset);
1727      IROffset -= SL->getElementOffset(FieldIdx);
1728
1729      return GetINTEGERTypeAtOffset(STy->getElementType(FieldIdx), IROffset,
1730                                    SourceTy, SourceOffset);
1731    }
1732  }
1733
1734  if (llvm::ArrayType *ATy = dyn_cast<llvm::ArrayType>(IRType)) {
1735    llvm::Type *EltTy = ATy->getElementType();
1736    unsigned EltSize = getTargetData().getTypeAllocSize(EltTy);
1737    unsigned EltOffset = IROffset/EltSize*EltSize;
1738    return GetINTEGERTypeAtOffset(EltTy, IROffset-EltOffset, SourceTy,
1739                                  SourceOffset);
1740  }
1741
1742  // Okay, we don't have any better idea of what to pass, so we pass this in an
1743  // integer register that isn't too big to fit the rest of the struct.
1744  unsigned TySizeInBytes =
1745    (unsigned)getContext().getTypeSizeInChars(SourceTy).getQuantity();
1746
1747  assert(TySizeInBytes != SourceOffset && "Empty field?");
1748
1749  // It is always safe to classify this as an integer type up to i64 that
1750  // isn't larger than the structure.
1751  return llvm::IntegerType::get(getVMContext(),
1752                                std::min(TySizeInBytes-SourceOffset, 8U)*8);
1753}
1754
1755
1756/// GetX86_64ByValArgumentPair - Given a high and low type that can ideally
1757/// be used as elements of a two register pair to pass or return, return a
1758/// first class aggregate to represent them.  For example, if the low part of
1759/// a by-value argument should be passed as i32* and the high part as float,
1760/// return {i32*, float}.
1761static llvm::Type *
1762GetX86_64ByValArgumentPair(llvm::Type *Lo, llvm::Type *Hi,
1763                           const llvm::TargetData &TD) {
1764  // In order to correctly satisfy the ABI, we need to the high part to start
1765  // at offset 8.  If the high and low parts we inferred are both 4-byte types
1766  // (e.g. i32 and i32) then the resultant struct type ({i32,i32}) won't have
1767  // the second element at offset 8.  Check for this:
1768  unsigned LoSize = (unsigned)TD.getTypeAllocSize(Lo);
1769  unsigned HiAlign = TD.getABITypeAlignment(Hi);
1770  unsigned HiStart = llvm::TargetData::RoundUpAlignment(LoSize, HiAlign);
1771  assert(HiStart != 0 && HiStart <= 8 && "Invalid x86-64 argument pair!");
1772
1773  // To handle this, we have to increase the size of the low part so that the
1774  // second element will start at an 8 byte offset.  We can't increase the size
1775  // of the second element because it might make us access off the end of the
1776  // struct.
1777  if (HiStart != 8) {
1778    // There are only two sorts of types the ABI generation code can produce for
1779    // the low part of a pair that aren't 8 bytes in size: float or i8/i16/i32.
1780    // Promote these to a larger type.
1781    if (Lo->isFloatTy())
1782      Lo = llvm::Type::getDoubleTy(Lo->getContext());
1783    else {
1784      assert(Lo->isIntegerTy() && "Invalid/unknown lo type");
1785      Lo = llvm::Type::getInt64Ty(Lo->getContext());
1786    }
1787  }
1788
1789  llvm::StructType *Result = llvm::StructType::get(Lo, Hi, NULL);
1790
1791
1792  // Verify that the second element is at an 8-byte offset.
1793  assert(TD.getStructLayout(Result)->getElementOffset(1) == 8 &&
1794         "Invalid x86-64 argument pair!");
1795  return Result;
1796}
1797
1798ABIArgInfo X86_64ABIInfo::
1799classifyReturnType(QualType RetTy) const {
1800  // AMD64-ABI 3.2.3p4: Rule 1. Classify the return type with the
1801  // classification algorithm.
1802  X86_64ABIInfo::Class Lo, Hi;
1803  classify(RetTy, 0, Lo, Hi);
1804
1805  // Check some invariants.
1806  assert((Hi != Memory || Lo == Memory) && "Invalid memory classification.");
1807  assert((Hi != SSEUp || Lo == SSE) && "Invalid SSEUp classification.");
1808
1809  llvm::Type *ResType = 0;
1810  switch (Lo) {
1811  case NoClass:
1812    if (Hi == NoClass)
1813      return ABIArgInfo::getIgnore();
1814    // If the low part is just padding, it takes no register, leave ResType
1815    // null.
1816    assert((Hi == SSE || Hi == Integer || Hi == X87Up) &&
1817           "Unknown missing lo part");
1818    break;
1819
1820  case SSEUp:
1821  case X87Up:
1822    llvm_unreachable("Invalid classification for lo word.");
1823
1824    // AMD64-ABI 3.2.3p4: Rule 2. Types of class memory are returned via
1825    // hidden argument.
1826  case Memory:
1827    return getIndirectReturnResult(RetTy);
1828
1829    // AMD64-ABI 3.2.3p4: Rule 3. If the class is INTEGER, the next
1830    // available register of the sequence %rax, %rdx is used.
1831  case Integer:
1832    ResType = GetINTEGERTypeAtOffset(CGT.ConvertType(RetTy), 0, RetTy, 0);
1833
1834    // If we have a sign or zero extended integer, make sure to return Extend
1835    // so that the parameter gets the right LLVM IR attributes.
1836    if (Hi == NoClass && isa<llvm::IntegerType>(ResType)) {
1837      // Treat an enum type as its underlying type.
1838      if (const EnumType *EnumTy = RetTy->getAs<EnumType>())
1839        RetTy = EnumTy->getDecl()->getIntegerType();
1840
1841      if (RetTy->isIntegralOrEnumerationType() &&
1842          RetTy->isPromotableIntegerType())
1843        return ABIArgInfo::getExtend();
1844    }
1845    break;
1846
1847    // AMD64-ABI 3.2.3p4: Rule 4. If the class is SSE, the next
1848    // available SSE register of the sequence %xmm0, %xmm1 is used.
1849  case SSE:
1850    ResType = GetSSETypeAtOffset(CGT.ConvertType(RetTy), 0, RetTy, 0);
1851    break;
1852
1853    // AMD64-ABI 3.2.3p4: Rule 6. If the class is X87, the value is
1854    // returned on the X87 stack in %st0 as 80-bit x87 number.
1855  case X87:
1856    ResType = llvm::Type::getX86_FP80Ty(getVMContext());
1857    break;
1858
1859    // AMD64-ABI 3.2.3p4: Rule 8. If the class is COMPLEX_X87, the real
1860    // part of the value is returned in %st0 and the imaginary part in
1861    // %st1.
1862  case ComplexX87:
1863    assert(Hi == ComplexX87 && "Unexpected ComplexX87 classification.");
1864    ResType = llvm::StructType::get(llvm::Type::getX86_FP80Ty(getVMContext()),
1865                                    llvm::Type::getX86_FP80Ty(getVMContext()),
1866                                    NULL);
1867    break;
1868  }
1869
1870  llvm::Type *HighPart = 0;
1871  switch (Hi) {
1872    // Memory was handled previously and X87 should
1873    // never occur as a hi class.
1874  case Memory:
1875  case X87:
1876    llvm_unreachable("Invalid classification for hi word.");
1877
1878  case ComplexX87: // Previously handled.
1879  case NoClass:
1880    break;
1881
1882  case Integer:
1883    HighPart = GetINTEGERTypeAtOffset(CGT.ConvertType(RetTy), 8, RetTy, 8);
1884    if (Lo == NoClass)  // Return HighPart at offset 8 in memory.
1885      return ABIArgInfo::getDirect(HighPart, 8);
1886    break;
1887  case SSE:
1888    HighPart = GetSSETypeAtOffset(CGT.ConvertType(RetTy), 8, RetTy, 8);
1889    if (Lo == NoClass)  // Return HighPart at offset 8 in memory.
1890      return ABIArgInfo::getDirect(HighPart, 8);
1891    break;
1892
1893    // AMD64-ABI 3.2.3p4: Rule 5. If the class is SSEUP, the eightbyte
1894    // is passed in the next available eightbyte chunk if the last used
1895    // vector register.
1896    //
1897    // SSEUP should always be preceded by SSE, just widen.
1898  case SSEUp:
1899    assert(Lo == SSE && "Unexpected SSEUp classification.");
1900    ResType = GetByteVectorType(RetTy);
1901    break;
1902
1903    // AMD64-ABI 3.2.3p4: Rule 7. If the class is X87UP, the value is
1904    // returned together with the previous X87 value in %st0.
1905  case X87Up:
1906    // If X87Up is preceded by X87, we don't need to do
1907    // anything. However, in some cases with unions it may not be
1908    // preceded by X87. In such situations we follow gcc and pass the
1909    // extra bits in an SSE reg.
1910    if (Lo != X87) {
1911      HighPart = GetSSETypeAtOffset(CGT.ConvertType(RetTy), 8, RetTy, 8);
1912      if (Lo == NoClass)  // Return HighPart at offset 8 in memory.
1913        return ABIArgInfo::getDirect(HighPart, 8);
1914    }
1915    break;
1916  }
1917
1918  // If a high part was specified, merge it together with the low part.  It is
1919  // known to pass in the high eightbyte of the result.  We do this by forming a
1920  // first class struct aggregate with the high and low part: {low, high}
1921  if (HighPart)
1922    ResType = GetX86_64ByValArgumentPair(ResType, HighPart, getTargetData());
1923
1924  return ABIArgInfo::getDirect(ResType);
1925}
1926
1927ABIArgInfo X86_64ABIInfo::classifyArgumentType(
1928  QualType Ty, unsigned freeIntRegs, unsigned &neededInt, unsigned &neededSSE)
1929  const
1930{
1931  X86_64ABIInfo::Class Lo, Hi;
1932  classify(Ty, 0, Lo, Hi);
1933
1934  // Check some invariants.
1935  // FIXME: Enforce these by construction.
1936  assert((Hi != Memory || Lo == Memory) && "Invalid memory classification.");
1937  assert((Hi != SSEUp || Lo == SSE) && "Invalid SSEUp classification.");
1938
1939  neededInt = 0;
1940  neededSSE = 0;
1941  llvm::Type *ResType = 0;
1942  switch (Lo) {
1943  case NoClass:
1944    if (Hi == NoClass)
1945      return ABIArgInfo::getIgnore();
1946    // If the low part is just padding, it takes no register, leave ResType
1947    // null.
1948    assert((Hi == SSE || Hi == Integer || Hi == X87Up) &&
1949           "Unknown missing lo part");
1950    break;
1951
1952    // AMD64-ABI 3.2.3p3: Rule 1. If the class is MEMORY, pass the argument
1953    // on the stack.
1954  case Memory:
1955
1956    // AMD64-ABI 3.2.3p3: Rule 5. If the class is X87, X87UP or
1957    // COMPLEX_X87, it is passed in memory.
1958  case X87:
1959  case ComplexX87:
1960    if (isRecordWithNonTrivialDestructorOrCopyConstructor(Ty))
1961      ++neededInt;
1962    return getIndirectResult(Ty, freeIntRegs);
1963
1964  case SSEUp:
1965  case X87Up:
1966    llvm_unreachable("Invalid classification for lo word.");
1967
1968    // AMD64-ABI 3.2.3p3: Rule 2. If the class is INTEGER, the next
1969    // available register of the sequence %rdi, %rsi, %rdx, %rcx, %r8
1970    // and %r9 is used.
1971  case Integer:
1972    ++neededInt;
1973
1974    // Pick an 8-byte type based on the preferred type.
1975    ResType = GetINTEGERTypeAtOffset(CGT.ConvertType(Ty), 0, Ty, 0);
1976
1977    // If we have a sign or zero extended integer, make sure to return Extend
1978    // so that the parameter gets the right LLVM IR attributes.
1979    if (Hi == NoClass && isa<llvm::IntegerType>(ResType)) {
1980      // Treat an enum type as its underlying type.
1981      if (const EnumType *EnumTy = Ty->getAs<EnumType>())
1982        Ty = EnumTy->getDecl()->getIntegerType();
1983
1984      if (Ty->isIntegralOrEnumerationType() &&
1985          Ty->isPromotableIntegerType())
1986        return ABIArgInfo::getExtend();
1987    }
1988
1989    break;
1990
1991    // AMD64-ABI 3.2.3p3: Rule 3. If the class is SSE, the next
1992    // available SSE register is used, the registers are taken in the
1993    // order from %xmm0 to %xmm7.
1994  case SSE: {
1995    llvm::Type *IRType = CGT.ConvertType(Ty);
1996    ResType = GetSSETypeAtOffset(IRType, 0, Ty, 0);
1997    ++neededSSE;
1998    break;
1999  }
2000  }
2001
2002  llvm::Type *HighPart = 0;
2003  switch (Hi) {
2004    // Memory was handled previously, ComplexX87 and X87 should
2005    // never occur as hi classes, and X87Up must be preceded by X87,
2006    // which is passed in memory.
2007  case Memory:
2008  case X87:
2009  case ComplexX87:
2010    llvm_unreachable("Invalid classification for hi word.");
2011
2012  case NoClass: break;
2013
2014  case Integer:
2015    ++neededInt;
2016    // Pick an 8-byte type based on the preferred type.
2017    HighPart = GetINTEGERTypeAtOffset(CGT.ConvertType(Ty), 8, Ty, 8);
2018
2019    if (Lo == NoClass)  // Pass HighPart at offset 8 in memory.
2020      return ABIArgInfo::getDirect(HighPart, 8);
2021    break;
2022
2023    // X87Up generally doesn't occur here (long double is passed in
2024    // memory), except in situations involving unions.
2025  case X87Up:
2026  case SSE:
2027    HighPart = GetSSETypeAtOffset(CGT.ConvertType(Ty), 8, Ty, 8);
2028
2029    if (Lo == NoClass)  // Pass HighPart at offset 8 in memory.
2030      return ABIArgInfo::getDirect(HighPart, 8);
2031
2032    ++neededSSE;
2033    break;
2034
2035    // AMD64-ABI 3.2.3p3: Rule 4. If the class is SSEUP, the
2036    // eightbyte is passed in the upper half of the last used SSE
2037    // register.  This only happens when 128-bit vectors are passed.
2038  case SSEUp:
2039    assert(Lo == SSE && "Unexpected SSEUp classification");
2040    ResType = GetByteVectorType(Ty);
2041    break;
2042  }
2043
2044  // If a high part was specified, merge it together with the low part.  It is
2045  // known to pass in the high eightbyte of the result.  We do this by forming a
2046  // first class struct aggregate with the high and low part: {low, high}
2047  if (HighPart)
2048    ResType = GetX86_64ByValArgumentPair(ResType, HighPart, getTargetData());
2049
2050  return ABIArgInfo::getDirect(ResType);
2051}
2052
2053void X86_64ABIInfo::computeInfo(CGFunctionInfo &FI) const {
2054
2055  FI.getReturnInfo() = classifyReturnType(FI.getReturnType());
2056
2057  // Keep track of the number of assigned registers.
2058  unsigned freeIntRegs = 6, freeSSERegs = 8;
2059
2060  // If the return value is indirect, then the hidden argument is consuming one
2061  // integer register.
2062  if (FI.getReturnInfo().isIndirect())
2063    --freeIntRegs;
2064
2065  // AMD64-ABI 3.2.3p3: Once arguments are classified, the registers
2066  // get assigned (in left-to-right order) for passing as follows...
2067  for (CGFunctionInfo::arg_iterator it = FI.arg_begin(), ie = FI.arg_end();
2068       it != ie; ++it) {
2069    unsigned neededInt, neededSSE;
2070    it->info = classifyArgumentType(it->type, freeIntRegs, neededInt,
2071                                    neededSSE);
2072
2073    // AMD64-ABI 3.2.3p3: If there are no registers available for any
2074    // eightbyte of an argument, the whole argument is passed on the
2075    // stack. If registers have already been assigned for some
2076    // eightbytes of such an argument, the assignments get reverted.
2077    if (freeIntRegs >= neededInt && freeSSERegs >= neededSSE) {
2078      freeIntRegs -= neededInt;
2079      freeSSERegs -= neededSSE;
2080    } else {
2081      it->info = getIndirectResult(it->type, freeIntRegs);
2082    }
2083  }
2084}
2085
2086static llvm::Value *EmitVAArgFromMemory(llvm::Value *VAListAddr,
2087                                        QualType Ty,
2088                                        CodeGenFunction &CGF) {
2089  llvm::Value *overflow_arg_area_p =
2090    CGF.Builder.CreateStructGEP(VAListAddr, 2, "overflow_arg_area_p");
2091  llvm::Value *overflow_arg_area =
2092    CGF.Builder.CreateLoad(overflow_arg_area_p, "overflow_arg_area");
2093
2094  // AMD64-ABI 3.5.7p5: Step 7. Align l->overflow_arg_area upwards to a 16
2095  // byte boundary if alignment needed by type exceeds 8 byte boundary.
2096  // It isn't stated explicitly in the standard, but in practice we use
2097  // alignment greater than 16 where necessary.
2098  uint64_t Align = CGF.getContext().getTypeAlign(Ty) / 8;
2099  if (Align > 8) {
2100    // overflow_arg_area = (overflow_arg_area + align - 1) & -align;
2101    llvm::Value *Offset =
2102      llvm::ConstantInt::get(CGF.Int64Ty, Align - 1);
2103    overflow_arg_area = CGF.Builder.CreateGEP(overflow_arg_area, Offset);
2104    llvm::Value *AsInt = CGF.Builder.CreatePtrToInt(overflow_arg_area,
2105                                                    CGF.Int64Ty);
2106    llvm::Value *Mask = llvm::ConstantInt::get(CGF.Int64Ty, -(uint64_t)Align);
2107    overflow_arg_area =
2108      CGF.Builder.CreateIntToPtr(CGF.Builder.CreateAnd(AsInt, Mask),
2109                                 overflow_arg_area->getType(),
2110                                 "overflow_arg_area.align");
2111  }
2112
2113  // AMD64-ABI 3.5.7p5: Step 8. Fetch type from l->overflow_arg_area.
2114  llvm::Type *LTy = CGF.ConvertTypeForMem(Ty);
2115  llvm::Value *Res =
2116    CGF.Builder.CreateBitCast(overflow_arg_area,
2117                              llvm::PointerType::getUnqual(LTy));
2118
2119  // AMD64-ABI 3.5.7p5: Step 9. Set l->overflow_arg_area to:
2120  // l->overflow_arg_area + sizeof(type).
2121  // AMD64-ABI 3.5.7p5: Step 10. Align l->overflow_arg_area upwards to
2122  // an 8 byte boundary.
2123
2124  uint64_t SizeInBytes = (CGF.getContext().getTypeSize(Ty) + 7) / 8;
2125  llvm::Value *Offset =
2126      llvm::ConstantInt::get(CGF.Int32Ty, (SizeInBytes + 7)  & ~7);
2127  overflow_arg_area = CGF.Builder.CreateGEP(overflow_arg_area, Offset,
2128                                            "overflow_arg_area.next");
2129  CGF.Builder.CreateStore(overflow_arg_area, overflow_arg_area_p);
2130
2131  // AMD64-ABI 3.5.7p5: Step 11. Return the fetched type.
2132  return Res;
2133}
2134
2135llvm::Value *X86_64ABIInfo::EmitVAArg(llvm::Value *VAListAddr, QualType Ty,
2136                                      CodeGenFunction &CGF) const {
2137  // Assume that va_list type is correct; should be pointer to LLVM type:
2138  // struct {
2139  //   i32 gp_offset;
2140  //   i32 fp_offset;
2141  //   i8* overflow_arg_area;
2142  //   i8* reg_save_area;
2143  // };
2144  unsigned neededInt, neededSSE;
2145
2146  Ty = CGF.getContext().getCanonicalType(Ty);
2147  ABIArgInfo AI = classifyArgumentType(Ty, 0, neededInt, neededSSE);
2148
2149  // AMD64-ABI 3.5.7p5: Step 1. Determine whether type may be passed
2150  // in the registers. If not go to step 7.
2151  if (!neededInt && !neededSSE)
2152    return EmitVAArgFromMemory(VAListAddr, Ty, CGF);
2153
2154  // AMD64-ABI 3.5.7p5: Step 2. Compute num_gp to hold the number of
2155  // general purpose registers needed to pass type and num_fp to hold
2156  // the number of floating point registers needed.
2157
2158  // AMD64-ABI 3.5.7p5: Step 3. Verify whether arguments fit into
2159  // registers. In the case: l->gp_offset > 48 - num_gp * 8 or
2160  // l->fp_offset > 304 - num_fp * 16 go to step 7.
2161  //
2162  // NOTE: 304 is a typo, there are (6 * 8 + 8 * 16) = 176 bytes of
2163  // register save space).
2164
2165  llvm::Value *InRegs = 0;
2166  llvm::Value *gp_offset_p = 0, *gp_offset = 0;
2167  llvm::Value *fp_offset_p = 0, *fp_offset = 0;
2168  if (neededInt) {
2169    gp_offset_p = CGF.Builder.CreateStructGEP(VAListAddr, 0, "gp_offset_p");
2170    gp_offset = CGF.Builder.CreateLoad(gp_offset_p, "gp_offset");
2171    InRegs = llvm::ConstantInt::get(CGF.Int32Ty, 48 - neededInt * 8);
2172    InRegs = CGF.Builder.CreateICmpULE(gp_offset, InRegs, "fits_in_gp");
2173  }
2174
2175  if (neededSSE) {
2176    fp_offset_p = CGF.Builder.CreateStructGEP(VAListAddr, 1, "fp_offset_p");
2177    fp_offset = CGF.Builder.CreateLoad(fp_offset_p, "fp_offset");
2178    llvm::Value *FitsInFP =
2179      llvm::ConstantInt::get(CGF.Int32Ty, 176 - neededSSE * 16);
2180    FitsInFP = CGF.Builder.CreateICmpULE(fp_offset, FitsInFP, "fits_in_fp");
2181    InRegs = InRegs ? CGF.Builder.CreateAnd(InRegs, FitsInFP) : FitsInFP;
2182  }
2183
2184  llvm::BasicBlock *InRegBlock = CGF.createBasicBlock("vaarg.in_reg");
2185  llvm::BasicBlock *InMemBlock = CGF.createBasicBlock("vaarg.in_mem");
2186  llvm::BasicBlock *ContBlock = CGF.createBasicBlock("vaarg.end");
2187  CGF.Builder.CreateCondBr(InRegs, InRegBlock, InMemBlock);
2188
2189  // Emit code to load the value if it was passed in registers.
2190
2191  CGF.EmitBlock(InRegBlock);
2192
2193  // AMD64-ABI 3.5.7p5: Step 4. Fetch type from l->reg_save_area with
2194  // an offset of l->gp_offset and/or l->fp_offset. This may require
2195  // copying to a temporary location in case the parameter is passed
2196  // in different register classes or requires an alignment greater
2197  // than 8 for general purpose registers and 16 for XMM registers.
2198  //
2199  // FIXME: This really results in shameful code when we end up needing to
2200  // collect arguments from different places; often what should result in a
2201  // simple assembling of a structure from scattered addresses has many more
2202  // loads than necessary. Can we clean this up?
2203  llvm::Type *LTy = CGF.ConvertTypeForMem(Ty);
2204  llvm::Value *RegAddr =
2205    CGF.Builder.CreateLoad(CGF.Builder.CreateStructGEP(VAListAddr, 3),
2206                           "reg_save_area");
2207  if (neededInt && neededSSE) {
2208    // FIXME: Cleanup.
2209    assert(AI.isDirect() && "Unexpected ABI info for mixed regs");
2210    llvm::StructType *ST = cast<llvm::StructType>(AI.getCoerceToType());
2211    llvm::Value *Tmp = CGF.CreateTempAlloca(ST);
2212    assert(ST->getNumElements() == 2 && "Unexpected ABI info for mixed regs");
2213    llvm::Type *TyLo = ST->getElementType(0);
2214    llvm::Type *TyHi = ST->getElementType(1);
2215    assert((TyLo->isFPOrFPVectorTy() ^ TyHi->isFPOrFPVectorTy()) &&
2216           "Unexpected ABI info for mixed regs");
2217    llvm::Type *PTyLo = llvm::PointerType::getUnqual(TyLo);
2218    llvm::Type *PTyHi = llvm::PointerType::getUnqual(TyHi);
2219    llvm::Value *GPAddr = CGF.Builder.CreateGEP(RegAddr, gp_offset);
2220    llvm::Value *FPAddr = CGF.Builder.CreateGEP(RegAddr, fp_offset);
2221    llvm::Value *RegLoAddr = TyLo->isFloatingPointTy() ? FPAddr : GPAddr;
2222    llvm::Value *RegHiAddr = TyLo->isFloatingPointTy() ? GPAddr : FPAddr;
2223    llvm::Value *V =
2224      CGF.Builder.CreateLoad(CGF.Builder.CreateBitCast(RegLoAddr, PTyLo));
2225    CGF.Builder.CreateStore(V, CGF.Builder.CreateStructGEP(Tmp, 0));
2226    V = CGF.Builder.CreateLoad(CGF.Builder.CreateBitCast(RegHiAddr, PTyHi));
2227    CGF.Builder.CreateStore(V, CGF.Builder.CreateStructGEP(Tmp, 1));
2228
2229    RegAddr = CGF.Builder.CreateBitCast(Tmp,
2230                                        llvm::PointerType::getUnqual(LTy));
2231  } else if (neededInt) {
2232    RegAddr = CGF.Builder.CreateGEP(RegAddr, gp_offset);
2233    RegAddr = CGF.Builder.CreateBitCast(RegAddr,
2234                                        llvm::PointerType::getUnqual(LTy));
2235  } else if (neededSSE == 1) {
2236    RegAddr = CGF.Builder.CreateGEP(RegAddr, fp_offset);
2237    RegAddr = CGF.Builder.CreateBitCast(RegAddr,
2238                                        llvm::PointerType::getUnqual(LTy));
2239  } else {
2240    assert(neededSSE == 2 && "Invalid number of needed registers!");
2241    // SSE registers are spaced 16 bytes apart in the register save
2242    // area, we need to collect the two eightbytes together.
2243    llvm::Value *RegAddrLo = CGF.Builder.CreateGEP(RegAddr, fp_offset);
2244    llvm::Value *RegAddrHi = CGF.Builder.CreateConstGEP1_32(RegAddrLo, 16);
2245    llvm::Type *DoubleTy = CGF.DoubleTy;
2246    llvm::Type *DblPtrTy =
2247      llvm::PointerType::getUnqual(DoubleTy);
2248    llvm::StructType *ST = llvm::StructType::get(DoubleTy,
2249                                                       DoubleTy, NULL);
2250    llvm::Value *V, *Tmp = CGF.CreateTempAlloca(ST);
2251    V = CGF.Builder.CreateLoad(CGF.Builder.CreateBitCast(RegAddrLo,
2252                                                         DblPtrTy));
2253    CGF.Builder.CreateStore(V, CGF.Builder.CreateStructGEP(Tmp, 0));
2254    V = CGF.Builder.CreateLoad(CGF.Builder.CreateBitCast(RegAddrHi,
2255                                                         DblPtrTy));
2256    CGF.Builder.CreateStore(V, CGF.Builder.CreateStructGEP(Tmp, 1));
2257    RegAddr = CGF.Builder.CreateBitCast(Tmp,
2258                                        llvm::PointerType::getUnqual(LTy));
2259  }
2260
2261  // AMD64-ABI 3.5.7p5: Step 5. Set:
2262  // l->gp_offset = l->gp_offset + num_gp * 8
2263  // l->fp_offset = l->fp_offset + num_fp * 16.
2264  if (neededInt) {
2265    llvm::Value *Offset = llvm::ConstantInt::get(CGF.Int32Ty, neededInt * 8);
2266    CGF.Builder.CreateStore(CGF.Builder.CreateAdd(gp_offset, Offset),
2267                            gp_offset_p);
2268  }
2269  if (neededSSE) {
2270    llvm::Value *Offset = llvm::ConstantInt::get(CGF.Int32Ty, neededSSE * 16);
2271    CGF.Builder.CreateStore(CGF.Builder.CreateAdd(fp_offset, Offset),
2272                            fp_offset_p);
2273  }
2274  CGF.EmitBranch(ContBlock);
2275
2276  // Emit code to load the value if it was passed in memory.
2277
2278  CGF.EmitBlock(InMemBlock);
2279  llvm::Value *MemAddr = EmitVAArgFromMemory(VAListAddr, Ty, CGF);
2280
2281  // Return the appropriate result.
2282
2283  CGF.EmitBlock(ContBlock);
2284  llvm::PHINode *ResAddr = CGF.Builder.CreatePHI(RegAddr->getType(), 2,
2285                                                 "vaarg.addr");
2286  ResAddr->addIncoming(RegAddr, InRegBlock);
2287  ResAddr->addIncoming(MemAddr, InMemBlock);
2288  return ResAddr;
2289}
2290
2291ABIArgInfo WinX86_64ABIInfo::classify(QualType Ty) const {
2292
2293  if (Ty->isVoidType())
2294    return ABIArgInfo::getIgnore();
2295
2296  if (const EnumType *EnumTy = Ty->getAs<EnumType>())
2297    Ty = EnumTy->getDecl()->getIntegerType();
2298
2299  uint64_t Size = getContext().getTypeSize(Ty);
2300
2301  if (const RecordType *RT = Ty->getAs<RecordType>()) {
2302    if (hasNonTrivialDestructorOrCopyConstructor(RT) ||
2303        RT->getDecl()->hasFlexibleArrayMember())
2304      return ABIArgInfo::getIndirect(0, /*ByVal=*/false);
2305
2306    // FIXME: mingw-w64-gcc emits 128-bit struct as i128
2307    if (Size == 128 &&
2308        getContext().getTargetInfo().getTriple().getOS()
2309          == llvm::Triple::MinGW32)
2310      return ABIArgInfo::getDirect(llvm::IntegerType::get(getVMContext(),
2311                                                          Size));
2312
2313    // MS x64 ABI requirement: "Any argument that doesn't fit in 8 bytes, or is
2314    // not 1, 2, 4, or 8 bytes, must be passed by reference."
2315    if (Size <= 64 &&
2316        (Size & (Size - 1)) == 0)
2317      return ABIArgInfo::getDirect(llvm::IntegerType::get(getVMContext(),
2318                                                          Size));
2319
2320    return ABIArgInfo::getIndirect(0, /*ByVal=*/false);
2321  }
2322
2323  if (Ty->isPromotableIntegerType())
2324    return ABIArgInfo::getExtend();
2325
2326  return ABIArgInfo::getDirect();
2327}
2328
2329void WinX86_64ABIInfo::computeInfo(CGFunctionInfo &FI) const {
2330
2331  QualType RetTy = FI.getReturnType();
2332  FI.getReturnInfo() = classify(RetTy);
2333
2334  for (CGFunctionInfo::arg_iterator it = FI.arg_begin(), ie = FI.arg_end();
2335       it != ie; ++it)
2336    it->info = classify(it->type);
2337}
2338
2339llvm::Value *WinX86_64ABIInfo::EmitVAArg(llvm::Value *VAListAddr, QualType Ty,
2340                                      CodeGenFunction &CGF) const {
2341  llvm::Type *BPP = CGF.Int8PtrPtrTy;
2342
2343  CGBuilderTy &Builder = CGF.Builder;
2344  llvm::Value *VAListAddrAsBPP = Builder.CreateBitCast(VAListAddr, BPP,
2345                                                       "ap");
2346  llvm::Value *Addr = Builder.CreateLoad(VAListAddrAsBPP, "ap.cur");
2347  llvm::Type *PTy =
2348    llvm::PointerType::getUnqual(CGF.ConvertType(Ty));
2349  llvm::Value *AddrTyped = Builder.CreateBitCast(Addr, PTy);
2350
2351  uint64_t Offset =
2352    llvm::RoundUpToAlignment(CGF.getContext().getTypeSize(Ty) / 8, 8);
2353  llvm::Value *NextAddr =
2354    Builder.CreateGEP(Addr, llvm::ConstantInt::get(CGF.Int32Ty, Offset),
2355                      "ap.next");
2356  Builder.CreateStore(NextAddr, VAListAddrAsBPP);
2357
2358  return AddrTyped;
2359}
2360
2361// PowerPC-32
2362
2363namespace {
2364class PPC32TargetCodeGenInfo : public DefaultTargetCodeGenInfo {
2365public:
2366  PPC32TargetCodeGenInfo(CodeGenTypes &CGT) : DefaultTargetCodeGenInfo(CGT) {}
2367
2368  int getDwarfEHStackPointer(CodeGen::CodeGenModule &M) const {
2369    // This is recovered from gcc output.
2370    return 1; // r1 is the dedicated stack pointer
2371  }
2372
2373  bool initDwarfEHRegSizeTable(CodeGen::CodeGenFunction &CGF,
2374                               llvm::Value *Address) const;
2375};
2376
2377}
2378
2379bool
2380PPC32TargetCodeGenInfo::initDwarfEHRegSizeTable(CodeGen::CodeGenFunction &CGF,
2381                                                llvm::Value *Address) const {
2382  // This is calculated from the LLVM and GCC tables and verified
2383  // against gcc output.  AFAIK all ABIs use the same encoding.
2384
2385  CodeGen::CGBuilderTy &Builder = CGF.Builder;
2386
2387  llvm::IntegerType *i8 = CGF.Int8Ty;
2388  llvm::Value *Four8 = llvm::ConstantInt::get(i8, 4);
2389  llvm::Value *Eight8 = llvm::ConstantInt::get(i8, 8);
2390  llvm::Value *Sixteen8 = llvm::ConstantInt::get(i8, 16);
2391
2392  // 0-31: r0-31, the 4-byte general-purpose registers
2393  AssignToArrayRange(Builder, Address, Four8, 0, 31);
2394
2395  // 32-63: fp0-31, the 8-byte floating-point registers
2396  AssignToArrayRange(Builder, Address, Eight8, 32, 63);
2397
2398  // 64-76 are various 4-byte special-purpose registers:
2399  // 64: mq
2400  // 65: lr
2401  // 66: ctr
2402  // 67: ap
2403  // 68-75 cr0-7
2404  // 76: xer
2405  AssignToArrayRange(Builder, Address, Four8, 64, 76);
2406
2407  // 77-108: v0-31, the 16-byte vector registers
2408  AssignToArrayRange(Builder, Address, Sixteen8, 77, 108);
2409
2410  // 109: vrsave
2411  // 110: vscr
2412  // 111: spe_acc
2413  // 112: spefscr
2414  // 113: sfp
2415  AssignToArrayRange(Builder, Address, Four8, 109, 113);
2416
2417  return false;
2418}
2419
2420// PowerPC-64
2421
2422namespace {
2423class PPC64TargetCodeGenInfo : public DefaultTargetCodeGenInfo {
2424public:
2425  PPC64TargetCodeGenInfo(CodeGenTypes &CGT) : DefaultTargetCodeGenInfo(CGT) {}
2426
2427  int getDwarfEHStackPointer(CodeGen::CodeGenModule &M) const {
2428    // This is recovered from gcc output.
2429    return 1; // r1 is the dedicated stack pointer
2430  }
2431
2432  bool initDwarfEHRegSizeTable(CodeGen::CodeGenFunction &CGF,
2433                               llvm::Value *Address) const;
2434};
2435
2436}
2437
2438bool
2439PPC64TargetCodeGenInfo::initDwarfEHRegSizeTable(CodeGen::CodeGenFunction &CGF,
2440                                                llvm::Value *Address) const {
2441  // This is calculated from the LLVM and GCC tables and verified
2442  // against gcc output.  AFAIK all ABIs use the same encoding.
2443
2444  CodeGen::CGBuilderTy &Builder = CGF.Builder;
2445
2446  llvm::IntegerType *i8 = CGF.Int8Ty;
2447  llvm::Value *Four8 = llvm::ConstantInt::get(i8, 4);
2448  llvm::Value *Eight8 = llvm::ConstantInt::get(i8, 8);
2449  llvm::Value *Sixteen8 = llvm::ConstantInt::get(i8, 16);
2450
2451  // 0-31: r0-31, the 8-byte general-purpose registers
2452  AssignToArrayRange(Builder, Address, Eight8, 0, 31);
2453
2454  // 32-63: fp0-31, the 8-byte floating-point registers
2455  AssignToArrayRange(Builder, Address, Eight8, 32, 63);
2456
2457  // 64-76 are various 4-byte special-purpose registers:
2458  // 64: mq
2459  // 65: lr
2460  // 66: ctr
2461  // 67: ap
2462  // 68-75 cr0-7
2463  // 76: xer
2464  AssignToArrayRange(Builder, Address, Four8, 64, 76);
2465
2466  // 77-108: v0-31, the 16-byte vector registers
2467  AssignToArrayRange(Builder, Address, Sixteen8, 77, 108);
2468
2469  // 109: vrsave
2470  // 110: vscr
2471  // 111: spe_acc
2472  // 112: spefscr
2473  // 113: sfp
2474  AssignToArrayRange(Builder, Address, Four8, 109, 113);
2475
2476  return false;
2477}
2478
2479//===----------------------------------------------------------------------===//
2480// ARM ABI Implementation
2481//===----------------------------------------------------------------------===//
2482
2483namespace {
2484
2485class ARMABIInfo : public ABIInfo {
2486public:
2487  enum ABIKind {
2488    APCS = 0,
2489    AAPCS = 1,
2490    AAPCS_VFP
2491  };
2492
2493private:
2494  ABIKind Kind;
2495
2496public:
2497  ARMABIInfo(CodeGenTypes &CGT, ABIKind _Kind) : ABIInfo(CGT), Kind(_Kind) {}
2498
2499  bool isEABI() const {
2500    StringRef Env =
2501      getContext().getTargetInfo().getTriple().getEnvironmentName();
2502    return (Env == "gnueabi" || Env == "eabi" || Env == "androideabi");
2503  }
2504
2505private:
2506  ABIKind getABIKind() const { return Kind; }
2507
2508  ABIArgInfo classifyReturnType(QualType RetTy) const;
2509  ABIArgInfo classifyArgumentType(QualType RetTy) const;
2510
2511  virtual void computeInfo(CGFunctionInfo &FI) const;
2512
2513  virtual llvm::Value *EmitVAArg(llvm::Value *VAListAddr, QualType Ty,
2514                                 CodeGenFunction &CGF) const;
2515};
2516
2517class ARMTargetCodeGenInfo : public TargetCodeGenInfo {
2518public:
2519  ARMTargetCodeGenInfo(CodeGenTypes &CGT, ARMABIInfo::ABIKind K)
2520    :TargetCodeGenInfo(new ARMABIInfo(CGT, K)) {}
2521
2522  const ARMABIInfo &getABIInfo() const {
2523    return static_cast<const ARMABIInfo&>(TargetCodeGenInfo::getABIInfo());
2524  }
2525
2526  int getDwarfEHStackPointer(CodeGen::CodeGenModule &M) const {
2527    return 13;
2528  }
2529
2530  StringRef getARCRetainAutoreleasedReturnValueMarker() const {
2531    return "mov\tr7, r7\t\t@ marker for objc_retainAutoreleaseReturnValue";
2532  }
2533
2534  bool initDwarfEHRegSizeTable(CodeGen::CodeGenFunction &CGF,
2535                               llvm::Value *Address) const {
2536    llvm::Value *Four8 = llvm::ConstantInt::get(CGF.Int8Ty, 4);
2537
2538    // 0-15 are the 16 integer registers.
2539    AssignToArrayRange(CGF.Builder, Address, Four8, 0, 15);
2540    return false;
2541  }
2542
2543  unsigned getSizeOfUnwindException() const {
2544    if (getABIInfo().isEABI()) return 88;
2545    return TargetCodeGenInfo::getSizeOfUnwindException();
2546  }
2547};
2548
2549}
2550
2551void ARMABIInfo::computeInfo(CGFunctionInfo &FI) const {
2552  FI.getReturnInfo() = classifyReturnType(FI.getReturnType());
2553  for (CGFunctionInfo::arg_iterator it = FI.arg_begin(), ie = FI.arg_end();
2554       it != ie; ++it)
2555    it->info = classifyArgumentType(it->type);
2556
2557  // Always honor user-specified calling convention.
2558  if (FI.getCallingConvention() != llvm::CallingConv::C)
2559    return;
2560
2561  // Calling convention as default by an ABI.
2562  llvm::CallingConv::ID DefaultCC;
2563  if (isEABI())
2564    DefaultCC = llvm::CallingConv::ARM_AAPCS;
2565  else
2566    DefaultCC = llvm::CallingConv::ARM_APCS;
2567
2568  // If user did not ask for specific calling convention explicitly (e.g. via
2569  // pcs attribute), set effective calling convention if it's different than ABI
2570  // default.
2571  switch (getABIKind()) {
2572  case APCS:
2573    if (DefaultCC != llvm::CallingConv::ARM_APCS)
2574      FI.setEffectiveCallingConvention(llvm::CallingConv::ARM_APCS);
2575    break;
2576  case AAPCS:
2577    if (DefaultCC != llvm::CallingConv::ARM_AAPCS)
2578      FI.setEffectiveCallingConvention(llvm::CallingConv::ARM_AAPCS);
2579    break;
2580  case AAPCS_VFP:
2581    if (DefaultCC != llvm::CallingConv::ARM_AAPCS_VFP)
2582      FI.setEffectiveCallingConvention(llvm::CallingConv::ARM_AAPCS_VFP);
2583    break;
2584  }
2585}
2586
2587/// isHomogeneousAggregate - Return true if a type is an AAPCS-VFP homogeneous
2588/// aggregate.  If HAMembers is non-null, the number of base elements
2589/// contained in the type is returned through it; this is used for the
2590/// recursive calls that check aggregate component types.
2591static bool isHomogeneousAggregate(QualType Ty, const Type *&Base,
2592                                   ASTContext &Context,
2593                                   uint64_t *HAMembers = 0) {
2594  uint64_t Members = 0;
2595  if (const ConstantArrayType *AT = Context.getAsConstantArrayType(Ty)) {
2596    if (!isHomogeneousAggregate(AT->getElementType(), Base, Context, &Members))
2597      return false;
2598    Members *= AT->getSize().getZExtValue();
2599  } else if (const RecordType *RT = Ty->getAs<RecordType>()) {
2600    const RecordDecl *RD = RT->getDecl();
2601    if (RD->hasFlexibleArrayMember())
2602      return false;
2603
2604    Members = 0;
2605    for (RecordDecl::field_iterator i = RD->field_begin(), e = RD->field_end();
2606         i != e; ++i) {
2607      const FieldDecl *FD = *i;
2608      uint64_t FldMembers;
2609      if (!isHomogeneousAggregate(FD->getType(), Base, Context, &FldMembers))
2610        return false;
2611
2612      Members = (RD->isUnion() ?
2613                 std::max(Members, FldMembers) : Members + FldMembers);
2614    }
2615  } else {
2616    Members = 1;
2617    if (const ComplexType *CT = Ty->getAs<ComplexType>()) {
2618      Members = 2;
2619      Ty = CT->getElementType();
2620    }
2621
2622    // Homogeneous aggregates for AAPCS-VFP must have base types of float,
2623    // double, or 64-bit or 128-bit vectors.
2624    if (const BuiltinType *BT = Ty->getAs<BuiltinType>()) {
2625      if (BT->getKind() != BuiltinType::Float &&
2626          BT->getKind() != BuiltinType::Double &&
2627          BT->getKind() != BuiltinType::LongDouble)
2628        return false;
2629    } else if (const VectorType *VT = Ty->getAs<VectorType>()) {
2630      unsigned VecSize = Context.getTypeSize(VT);
2631      if (VecSize != 64 && VecSize != 128)
2632        return false;
2633    } else {
2634      return false;
2635    }
2636
2637    // The base type must be the same for all members.  Vector types of the
2638    // same total size are treated as being equivalent here.
2639    const Type *TyPtr = Ty.getTypePtr();
2640    if (!Base)
2641      Base = TyPtr;
2642    if (Base != TyPtr &&
2643        (!Base->isVectorType() || !TyPtr->isVectorType() ||
2644         Context.getTypeSize(Base) != Context.getTypeSize(TyPtr)))
2645      return false;
2646  }
2647
2648  // Homogeneous Aggregates can have at most 4 members of the base type.
2649  if (HAMembers)
2650    *HAMembers = Members;
2651
2652  return (Members > 0 && Members <= 4);
2653}
2654
2655ABIArgInfo ARMABIInfo::classifyArgumentType(QualType Ty) const {
2656  if (!isAggregateTypeForABI(Ty)) {
2657    // Treat an enum type as its underlying type.
2658    if (const EnumType *EnumTy = Ty->getAs<EnumType>())
2659      Ty = EnumTy->getDecl()->getIntegerType();
2660
2661    return (Ty->isPromotableIntegerType() ?
2662            ABIArgInfo::getExtend() : ABIArgInfo::getDirect());
2663  }
2664
2665  // Ignore empty records.
2666  if (isEmptyRecord(getContext(), Ty, true))
2667    return ABIArgInfo::getIgnore();
2668
2669  // Structures with either a non-trivial destructor or a non-trivial
2670  // copy constructor are always indirect.
2671  if (isRecordWithNonTrivialDestructorOrCopyConstructor(Ty))
2672    return ABIArgInfo::getIndirect(0, /*ByVal=*/false);
2673
2674  if (getABIKind() == ARMABIInfo::AAPCS_VFP) {
2675    // Homogeneous Aggregates need to be expanded.
2676    const Type *Base = 0;
2677    if (isHomogeneousAggregate(Ty, Base, getContext())) {
2678      assert(Base && "Base class should be set for homogeneous aggregate");
2679      return ABIArgInfo::getExpand();
2680    }
2681  }
2682
2683  // Otherwise, pass by coercing to a structure of the appropriate size.
2684  //
2685  // FIXME: This doesn't handle alignment > 64 bits.
2686  llvm::Type* ElemTy;
2687  unsigned SizeRegs;
2688  if (getContext().getTypeSizeInChars(Ty) <= CharUnits::fromQuantity(64)) {
2689    ElemTy = llvm::Type::getInt32Ty(getVMContext());
2690    SizeRegs = (getContext().getTypeSize(Ty) + 31) / 32;
2691  } else if (getABIKind() == ARMABIInfo::APCS) {
2692    // Initial ARM ByVal support is APCS-only.
2693    return ABIArgInfo::getIndirect(0, /*ByVal=*/true);
2694  } else {
2695    // FIXME: This is kind of nasty... but there isn't much choice
2696    // because most of the ARM calling conventions don't yet support
2697    // byval.
2698    ElemTy = llvm::Type::getInt64Ty(getVMContext());
2699    SizeRegs = (getContext().getTypeSize(Ty) + 63) / 64;
2700  }
2701
2702  llvm::Type *STy =
2703    llvm::StructType::get(llvm::ArrayType::get(ElemTy, SizeRegs), NULL);
2704  return ABIArgInfo::getDirect(STy);
2705}
2706
2707static bool isIntegerLikeType(QualType Ty, ASTContext &Context,
2708                              llvm::LLVMContext &VMContext) {
2709  // APCS, C Language Calling Conventions, Non-Simple Return Values: A structure
2710  // is called integer-like if its size is less than or equal to one word, and
2711  // the offset of each of its addressable sub-fields is zero.
2712
2713  uint64_t Size = Context.getTypeSize(Ty);
2714
2715  // Check that the type fits in a word.
2716  if (Size > 32)
2717    return false;
2718
2719  // FIXME: Handle vector types!
2720  if (Ty->isVectorType())
2721    return false;
2722
2723  // Float types are never treated as "integer like".
2724  if (Ty->isRealFloatingType())
2725    return false;
2726
2727  // If this is a builtin or pointer type then it is ok.
2728  if (Ty->getAs<BuiltinType>() || Ty->isPointerType())
2729    return true;
2730
2731  // Small complex integer types are "integer like".
2732  if (const ComplexType *CT = Ty->getAs<ComplexType>())
2733    return isIntegerLikeType(CT->getElementType(), Context, VMContext);
2734
2735  // Single element and zero sized arrays should be allowed, by the definition
2736  // above, but they are not.
2737
2738  // Otherwise, it must be a record type.
2739  const RecordType *RT = Ty->getAs<RecordType>();
2740  if (!RT) return false;
2741
2742  // Ignore records with flexible arrays.
2743  const RecordDecl *RD = RT->getDecl();
2744  if (RD->hasFlexibleArrayMember())
2745    return false;
2746
2747  // Check that all sub-fields are at offset 0, and are themselves "integer
2748  // like".
2749  const ASTRecordLayout &Layout = Context.getASTRecordLayout(RD);
2750
2751  bool HadField = false;
2752  unsigned idx = 0;
2753  for (RecordDecl::field_iterator i = RD->field_begin(), e = RD->field_end();
2754       i != e; ++i, ++idx) {
2755    const FieldDecl *FD = *i;
2756
2757    // Bit-fields are not addressable, we only need to verify they are "integer
2758    // like". We still have to disallow a subsequent non-bitfield, for example:
2759    //   struct { int : 0; int x }
2760    // is non-integer like according to gcc.
2761    if (FD->isBitField()) {
2762      if (!RD->isUnion())
2763        HadField = true;
2764
2765      if (!isIntegerLikeType(FD->getType(), Context, VMContext))
2766        return false;
2767
2768      continue;
2769    }
2770
2771    // Check if this field is at offset 0.
2772    if (Layout.getFieldOffset(idx) != 0)
2773      return false;
2774
2775    if (!isIntegerLikeType(FD->getType(), Context, VMContext))
2776      return false;
2777
2778    // Only allow at most one field in a structure. This doesn't match the
2779    // wording above, but follows gcc in situations with a field following an
2780    // empty structure.
2781    if (!RD->isUnion()) {
2782      if (HadField)
2783        return false;
2784
2785      HadField = true;
2786    }
2787  }
2788
2789  return true;
2790}
2791
2792ABIArgInfo ARMABIInfo::classifyReturnType(QualType RetTy) const {
2793  if (RetTy->isVoidType())
2794    return ABIArgInfo::getIgnore();
2795
2796  // Large vector types should be returned via memory.
2797  if (RetTy->isVectorType() && getContext().getTypeSize(RetTy) > 128)
2798    return ABIArgInfo::getIndirect(0);
2799
2800  if (!isAggregateTypeForABI(RetTy)) {
2801    // Treat an enum type as its underlying type.
2802    if (const EnumType *EnumTy = RetTy->getAs<EnumType>())
2803      RetTy = EnumTy->getDecl()->getIntegerType();
2804
2805    return (RetTy->isPromotableIntegerType() ?
2806            ABIArgInfo::getExtend() : ABIArgInfo::getDirect());
2807  }
2808
2809  // Structures with either a non-trivial destructor or a non-trivial
2810  // copy constructor are always indirect.
2811  if (isRecordWithNonTrivialDestructorOrCopyConstructor(RetTy))
2812    return ABIArgInfo::getIndirect(0, /*ByVal=*/false);
2813
2814  // Are we following APCS?
2815  if (getABIKind() == APCS) {
2816    if (isEmptyRecord(getContext(), RetTy, false))
2817      return ABIArgInfo::getIgnore();
2818
2819    // Complex types are all returned as packed integers.
2820    //
2821    // FIXME: Consider using 2 x vector types if the back end handles them
2822    // correctly.
2823    if (RetTy->isAnyComplexType())
2824      return ABIArgInfo::getDirect(llvm::IntegerType::get(getVMContext(),
2825                                              getContext().getTypeSize(RetTy)));
2826
2827    // Integer like structures are returned in r0.
2828    if (isIntegerLikeType(RetTy, getContext(), getVMContext())) {
2829      // Return in the smallest viable integer type.
2830      uint64_t Size = getContext().getTypeSize(RetTy);
2831      if (Size <= 8)
2832        return ABIArgInfo::getDirect(llvm::Type::getInt8Ty(getVMContext()));
2833      if (Size <= 16)
2834        return ABIArgInfo::getDirect(llvm::Type::getInt16Ty(getVMContext()));
2835      return ABIArgInfo::getDirect(llvm::Type::getInt32Ty(getVMContext()));
2836    }
2837
2838    // Otherwise return in memory.
2839    return ABIArgInfo::getIndirect(0);
2840  }
2841
2842  // Otherwise this is an AAPCS variant.
2843
2844  if (isEmptyRecord(getContext(), RetTy, true))
2845    return ABIArgInfo::getIgnore();
2846
2847  // Check for homogeneous aggregates with AAPCS-VFP.
2848  if (getABIKind() == AAPCS_VFP) {
2849    const Type *Base = 0;
2850    if (isHomogeneousAggregate(RetTy, Base, getContext())) {
2851      assert(Base && "Base class should be set for homogeneous aggregate");
2852      // Homogeneous Aggregates are returned directly.
2853      return ABIArgInfo::getDirect();
2854    }
2855  }
2856
2857  // Aggregates <= 4 bytes are returned in r0; other aggregates
2858  // are returned indirectly.
2859  uint64_t Size = getContext().getTypeSize(RetTy);
2860  if (Size <= 32) {
2861    // Return in the smallest viable integer type.
2862    if (Size <= 8)
2863      return ABIArgInfo::getDirect(llvm::Type::getInt8Ty(getVMContext()));
2864    if (Size <= 16)
2865      return ABIArgInfo::getDirect(llvm::Type::getInt16Ty(getVMContext()));
2866    return ABIArgInfo::getDirect(llvm::Type::getInt32Ty(getVMContext()));
2867  }
2868
2869  return ABIArgInfo::getIndirect(0);
2870}
2871
2872llvm::Value *ARMABIInfo::EmitVAArg(llvm::Value *VAListAddr, QualType Ty,
2873                                   CodeGenFunction &CGF) const {
2874  llvm::Type *BP = CGF.Int8PtrTy;
2875  llvm::Type *BPP = CGF.Int8PtrPtrTy;
2876
2877  CGBuilderTy &Builder = CGF.Builder;
2878  llvm::Value *VAListAddrAsBPP = Builder.CreateBitCast(VAListAddr, BPP, "ap");
2879  llvm::Value *Addr = Builder.CreateLoad(VAListAddrAsBPP, "ap.cur");
2880  // Handle address alignment for type alignment > 32 bits
2881  uint64_t TyAlign = CGF.getContext().getTypeAlign(Ty) / 8;
2882  if (TyAlign > 4) {
2883    assert((TyAlign & (TyAlign - 1)) == 0 &&
2884           "Alignment is not power of 2!");
2885    llvm::Value *AddrAsInt = Builder.CreatePtrToInt(Addr, CGF.Int32Ty);
2886    AddrAsInt = Builder.CreateAdd(AddrAsInt, Builder.getInt32(TyAlign - 1));
2887    AddrAsInt = Builder.CreateAnd(AddrAsInt, Builder.getInt32(~(TyAlign - 1)));
2888    Addr = Builder.CreateIntToPtr(AddrAsInt, BP);
2889  }
2890  llvm::Type *PTy =
2891    llvm::PointerType::getUnqual(CGF.ConvertType(Ty));
2892  llvm::Value *AddrTyped = Builder.CreateBitCast(Addr, PTy);
2893
2894  uint64_t Offset =
2895    llvm::RoundUpToAlignment(CGF.getContext().getTypeSize(Ty) / 8, 4);
2896  llvm::Value *NextAddr =
2897    Builder.CreateGEP(Addr, llvm::ConstantInt::get(CGF.Int32Ty, Offset),
2898                      "ap.next");
2899  Builder.CreateStore(NextAddr, VAListAddrAsBPP);
2900
2901  return AddrTyped;
2902}
2903
2904//===----------------------------------------------------------------------===//
2905// NVPTX ABI Implementation
2906//===----------------------------------------------------------------------===//
2907
2908namespace {
2909
2910class NVPTXABIInfo : public ABIInfo {
2911public:
2912  NVPTXABIInfo(CodeGenTypes &CGT) : ABIInfo(CGT) {}
2913
2914  ABIArgInfo classifyReturnType(QualType RetTy) const;
2915  ABIArgInfo classifyArgumentType(QualType Ty) const;
2916
2917  virtual void computeInfo(CGFunctionInfo &FI) const;
2918  virtual llvm::Value *EmitVAArg(llvm::Value *VAListAddr, QualType Ty,
2919                                 CodeGenFunction &CFG) const;
2920};
2921
2922class NVPTXTargetCodeGenInfo : public TargetCodeGenInfo {
2923public:
2924  NVPTXTargetCodeGenInfo(CodeGenTypes &CGT)
2925    : TargetCodeGenInfo(new NVPTXABIInfo(CGT)) {}
2926
2927  virtual void SetTargetAttributes(const Decl *D, llvm::GlobalValue *GV,
2928                                   CodeGen::CodeGenModule &M) const;
2929};
2930
2931ABIArgInfo NVPTXABIInfo::classifyReturnType(QualType RetTy) const {
2932  if (RetTy->isVoidType())
2933    return ABIArgInfo::getIgnore();
2934  if (isAggregateTypeForABI(RetTy))
2935    return ABIArgInfo::getIndirect(0);
2936  return ABIArgInfo::getDirect();
2937}
2938
2939ABIArgInfo NVPTXABIInfo::classifyArgumentType(QualType Ty) const {
2940  if (isAggregateTypeForABI(Ty))
2941    return ABIArgInfo::getIndirect(0);
2942
2943  return ABIArgInfo::getDirect();
2944}
2945
2946void NVPTXABIInfo::computeInfo(CGFunctionInfo &FI) const {
2947  FI.getReturnInfo() = classifyReturnType(FI.getReturnType());
2948  for (CGFunctionInfo::arg_iterator it = FI.arg_begin(), ie = FI.arg_end();
2949       it != ie; ++it)
2950    it->info = classifyArgumentType(it->type);
2951
2952  // Always honor user-specified calling convention.
2953  if (FI.getCallingConvention() != llvm::CallingConv::C)
2954    return;
2955
2956  // Calling convention as default by an ABI.
2957  // We're still using the PTX_Kernel/PTX_Device calling conventions here,
2958  // but we should switch to NVVM metadata later on.
2959  llvm::CallingConv::ID DefaultCC;
2960  const LangOptions &LangOpts = getContext().getLangOpts();
2961  if (LangOpts.OpenCL || LangOpts.CUDA) {
2962    // If we are in OpenCL or CUDA mode, then default to device functions
2963    DefaultCC = llvm::CallingConv::PTX_Device;
2964  } else {
2965    // If we are in standard C/C++ mode, use the triple to decide on the default
2966    StringRef Env =
2967      getContext().getTargetInfo().getTriple().getEnvironmentName();
2968    if (Env == "device")
2969      DefaultCC = llvm::CallingConv::PTX_Device;
2970    else
2971      DefaultCC = llvm::CallingConv::PTX_Kernel;
2972  }
2973  FI.setEffectiveCallingConvention(DefaultCC);
2974
2975}
2976
2977llvm::Value *NVPTXABIInfo::EmitVAArg(llvm::Value *VAListAddr, QualType Ty,
2978                                     CodeGenFunction &CFG) const {
2979  llvm_unreachable("NVPTX does not support varargs");
2980}
2981
2982void NVPTXTargetCodeGenInfo::
2983SetTargetAttributes(const Decl *D, llvm::GlobalValue *GV,
2984                    CodeGen::CodeGenModule &M) const{
2985  const FunctionDecl *FD = dyn_cast<FunctionDecl>(D);
2986  if (!FD) return;
2987
2988  llvm::Function *F = cast<llvm::Function>(GV);
2989
2990  // Perform special handling in OpenCL mode
2991  if (M.getLangOpts().OpenCL) {
2992    // Use OpenCL function attributes to set proper calling conventions
2993    // By default, all functions are device functions
2994    if (FD->hasAttr<OpenCLKernelAttr>()) {
2995      // OpenCL __kernel functions get a kernel calling convention
2996      F->setCallingConv(llvm::CallingConv::PTX_Kernel);
2997      // And kernel functions are not subject to inlining
2998      F->addFnAttr(llvm::Attribute::NoInline);
2999    }
3000  }
3001
3002  // Perform special handling in CUDA mode.
3003  if (M.getLangOpts().CUDA) {
3004    // CUDA __global__ functions get a kernel calling convention.  Since
3005    // __global__ functions cannot be called from the device, we do not
3006    // need to set the noinline attribute.
3007    if (FD->getAttr<CUDAGlobalAttr>())
3008      F->setCallingConv(llvm::CallingConv::PTX_Kernel);
3009  }
3010}
3011
3012}
3013
3014//===----------------------------------------------------------------------===//
3015// MBlaze ABI Implementation
3016//===----------------------------------------------------------------------===//
3017
3018namespace {
3019
3020class MBlazeABIInfo : public ABIInfo {
3021public:
3022  MBlazeABIInfo(CodeGenTypes &CGT) : ABIInfo(CGT) {}
3023
3024  bool isPromotableIntegerType(QualType Ty) const;
3025
3026  ABIArgInfo classifyReturnType(QualType RetTy) const;
3027  ABIArgInfo classifyArgumentType(QualType RetTy) const;
3028
3029  virtual void computeInfo(CGFunctionInfo &FI) const {
3030    FI.getReturnInfo() = classifyReturnType(FI.getReturnType());
3031    for (CGFunctionInfo::arg_iterator it = FI.arg_begin(), ie = FI.arg_end();
3032         it != ie; ++it)
3033      it->info = classifyArgumentType(it->type);
3034  }
3035
3036  virtual llvm::Value *EmitVAArg(llvm::Value *VAListAddr, QualType Ty,
3037                                 CodeGenFunction &CGF) const;
3038};
3039
3040class MBlazeTargetCodeGenInfo : public TargetCodeGenInfo {
3041public:
3042  MBlazeTargetCodeGenInfo(CodeGenTypes &CGT)
3043    : TargetCodeGenInfo(new MBlazeABIInfo(CGT)) {}
3044  void SetTargetAttributes(const Decl *D, llvm::GlobalValue *GV,
3045                           CodeGen::CodeGenModule &M) const;
3046};
3047
3048}
3049
3050bool MBlazeABIInfo::isPromotableIntegerType(QualType Ty) const {
3051  // MBlaze ABI requires all 8 and 16 bit quantities to be extended.
3052  if (const BuiltinType *BT = Ty->getAs<BuiltinType>())
3053    switch (BT->getKind()) {
3054    case BuiltinType::Bool:
3055    case BuiltinType::Char_S:
3056    case BuiltinType::Char_U:
3057    case BuiltinType::SChar:
3058    case BuiltinType::UChar:
3059    case BuiltinType::Short:
3060    case BuiltinType::UShort:
3061      return true;
3062    default:
3063      return false;
3064    }
3065  return false;
3066}
3067
3068llvm::Value *MBlazeABIInfo::EmitVAArg(llvm::Value *VAListAddr, QualType Ty,
3069                                      CodeGenFunction &CGF) const {
3070  // FIXME: Implement
3071  return 0;
3072}
3073
3074
3075ABIArgInfo MBlazeABIInfo::classifyReturnType(QualType RetTy) const {
3076  if (RetTy->isVoidType())
3077    return ABIArgInfo::getIgnore();
3078  if (isAggregateTypeForABI(RetTy))
3079    return ABIArgInfo::getIndirect(0);
3080
3081  return (isPromotableIntegerType(RetTy) ?
3082          ABIArgInfo::getExtend() : ABIArgInfo::getDirect());
3083}
3084
3085ABIArgInfo MBlazeABIInfo::classifyArgumentType(QualType Ty) const {
3086  if (isAggregateTypeForABI(Ty))
3087    return ABIArgInfo::getIndirect(0);
3088
3089  return (isPromotableIntegerType(Ty) ?
3090          ABIArgInfo::getExtend() : ABIArgInfo::getDirect());
3091}
3092
3093void MBlazeTargetCodeGenInfo::SetTargetAttributes(const Decl *D,
3094                                                  llvm::GlobalValue *GV,
3095                                                  CodeGen::CodeGenModule &M)
3096                                                  const {
3097  const FunctionDecl *FD = dyn_cast<FunctionDecl>(D);
3098  if (!FD) return;
3099
3100  llvm::CallingConv::ID CC = llvm::CallingConv::C;
3101  if (FD->hasAttr<MBlazeInterruptHandlerAttr>())
3102    CC = llvm::CallingConv::MBLAZE_INTR;
3103  else if (FD->hasAttr<MBlazeSaveVolatilesAttr>())
3104    CC = llvm::CallingConv::MBLAZE_SVOL;
3105
3106  if (CC != llvm::CallingConv::C) {
3107      // Handle 'interrupt_handler' attribute:
3108      llvm::Function *F = cast<llvm::Function>(GV);
3109
3110      // Step 1: Set ISR calling convention.
3111      F->setCallingConv(CC);
3112
3113      // Step 2: Add attributes goodness.
3114      F->addFnAttr(llvm::Attribute::NoInline);
3115  }
3116
3117  // Step 3: Emit _interrupt_handler alias.
3118  if (CC == llvm::CallingConv::MBLAZE_INTR)
3119    new llvm::GlobalAlias(GV->getType(), llvm::Function::ExternalLinkage,
3120                          "_interrupt_handler", GV, &M.getModule());
3121}
3122
3123
3124//===----------------------------------------------------------------------===//
3125// MSP430 ABI Implementation
3126//===----------------------------------------------------------------------===//
3127
3128namespace {
3129
3130class MSP430TargetCodeGenInfo : public TargetCodeGenInfo {
3131public:
3132  MSP430TargetCodeGenInfo(CodeGenTypes &CGT)
3133    : TargetCodeGenInfo(new DefaultABIInfo(CGT)) {}
3134  void SetTargetAttributes(const Decl *D, llvm::GlobalValue *GV,
3135                           CodeGen::CodeGenModule &M) const;
3136};
3137
3138}
3139
3140void MSP430TargetCodeGenInfo::SetTargetAttributes(const Decl *D,
3141                                                  llvm::GlobalValue *GV,
3142                                             CodeGen::CodeGenModule &M) const {
3143  if (const FunctionDecl *FD = dyn_cast<FunctionDecl>(D)) {
3144    if (const MSP430InterruptAttr *attr = FD->getAttr<MSP430InterruptAttr>()) {
3145      // Handle 'interrupt' attribute:
3146      llvm::Function *F = cast<llvm::Function>(GV);
3147
3148      // Step 1: Set ISR calling convention.
3149      F->setCallingConv(llvm::CallingConv::MSP430_INTR);
3150
3151      // Step 2: Add attributes goodness.
3152      F->addFnAttr(llvm::Attribute::NoInline);
3153
3154      // Step 3: Emit ISR vector alias.
3155      unsigned Num = attr->getNumber() + 0xffe0;
3156      new llvm::GlobalAlias(GV->getType(), llvm::Function::ExternalLinkage,
3157                            "vector_" + Twine::utohexstr(Num),
3158                            GV, &M.getModule());
3159    }
3160  }
3161}
3162
3163//===----------------------------------------------------------------------===//
3164// MIPS ABI Implementation.  This works for both little-endian and
3165// big-endian variants.
3166//===----------------------------------------------------------------------===//
3167
3168namespace {
3169class MipsABIInfo : public ABIInfo {
3170  bool IsO32;
3171  unsigned MinABIStackAlignInBytes, StackAlignInBytes;
3172  void CoerceToIntArgs(uint64_t TySize,
3173                       SmallVector<llvm::Type*, 8> &ArgList) const;
3174  llvm::Type* HandleAggregates(QualType Ty, uint64_t TySize) const;
3175  llvm::Type* returnAggregateInRegs(QualType RetTy, uint64_t Size) const;
3176  llvm::Type* getPaddingType(uint64_t Align, uint64_t Offset) const;
3177public:
3178  MipsABIInfo(CodeGenTypes &CGT, bool _IsO32) :
3179    ABIInfo(CGT), IsO32(_IsO32), MinABIStackAlignInBytes(IsO32 ? 4 : 8),
3180    StackAlignInBytes(IsO32 ? 8 : 16) {}
3181
3182  ABIArgInfo classifyReturnType(QualType RetTy) const;
3183  ABIArgInfo classifyArgumentType(QualType RetTy, uint64_t &Offset) const;
3184  virtual void computeInfo(CGFunctionInfo &FI) const;
3185  virtual llvm::Value *EmitVAArg(llvm::Value *VAListAddr, QualType Ty,
3186                                 CodeGenFunction &CGF) const;
3187};
3188
3189class MIPSTargetCodeGenInfo : public TargetCodeGenInfo {
3190  unsigned SizeOfUnwindException;
3191public:
3192  MIPSTargetCodeGenInfo(CodeGenTypes &CGT, bool IsO32)
3193    : TargetCodeGenInfo(new MipsABIInfo(CGT, IsO32)),
3194      SizeOfUnwindException(IsO32 ? 24 : 32) {}
3195
3196  int getDwarfEHStackPointer(CodeGen::CodeGenModule &CGM) const {
3197    return 29;
3198  }
3199
3200  bool initDwarfEHRegSizeTable(CodeGen::CodeGenFunction &CGF,
3201                               llvm::Value *Address) const;
3202
3203  unsigned getSizeOfUnwindException() const {
3204    return SizeOfUnwindException;
3205  }
3206};
3207}
3208
3209void MipsABIInfo::CoerceToIntArgs(uint64_t TySize,
3210                                  SmallVector<llvm::Type*, 8> &ArgList) const {
3211  llvm::IntegerType *IntTy =
3212    llvm::IntegerType::get(getVMContext(), MinABIStackAlignInBytes * 8);
3213
3214  // Add (TySize / MinABIStackAlignInBytes) args of IntTy.
3215  for (unsigned N = TySize / (MinABIStackAlignInBytes * 8); N; --N)
3216    ArgList.push_back(IntTy);
3217
3218  // If necessary, add one more integer type to ArgList.
3219  unsigned R = TySize % (MinABIStackAlignInBytes * 8);
3220
3221  if (R)
3222    ArgList.push_back(llvm::IntegerType::get(getVMContext(), R));
3223}
3224
3225// In N32/64, an aligned double precision floating point field is passed in
3226// a register.
3227llvm::Type* MipsABIInfo::HandleAggregates(QualType Ty, uint64_t TySize) const {
3228  SmallVector<llvm::Type*, 8> ArgList, IntArgList;
3229
3230  if (IsO32) {
3231    CoerceToIntArgs(TySize, ArgList);
3232    return llvm::StructType::get(getVMContext(), ArgList);
3233  }
3234
3235  if (Ty->isComplexType())
3236    return CGT.ConvertType(Ty);
3237
3238  const RecordType *RT = Ty->getAs<RecordType>();
3239
3240  // Unions/vectors are passed in integer registers.
3241  if (!RT || !RT->isStructureOrClassType()) {
3242    CoerceToIntArgs(TySize, ArgList);
3243    return llvm::StructType::get(getVMContext(), ArgList);
3244  }
3245
3246  const RecordDecl *RD = RT->getDecl();
3247  const ASTRecordLayout &Layout = getContext().getASTRecordLayout(RD);
3248  assert(!(TySize % 8) && "Size of structure must be multiple of 8.");
3249
3250  uint64_t LastOffset = 0;
3251  unsigned idx = 0;
3252  llvm::IntegerType *I64 = llvm::IntegerType::get(getVMContext(), 64);
3253
3254  // Iterate over fields in the struct/class and check if there are any aligned
3255  // double fields.
3256  for (RecordDecl::field_iterator i = RD->field_begin(), e = RD->field_end();
3257       i != e; ++i, ++idx) {
3258    const QualType Ty = i->getType();
3259    const BuiltinType *BT = Ty->getAs<BuiltinType>();
3260
3261    if (!BT || BT->getKind() != BuiltinType::Double)
3262      continue;
3263
3264    uint64_t Offset = Layout.getFieldOffset(idx);
3265    if (Offset % 64) // Ignore doubles that are not aligned.
3266      continue;
3267
3268    // Add ((Offset - LastOffset) / 64) args of type i64.
3269    for (unsigned j = (Offset - LastOffset) / 64; j > 0; --j)
3270      ArgList.push_back(I64);
3271
3272    // Add double type.
3273    ArgList.push_back(llvm::Type::getDoubleTy(getVMContext()));
3274    LastOffset = Offset + 64;
3275  }
3276
3277  CoerceToIntArgs(TySize - LastOffset, IntArgList);
3278  ArgList.append(IntArgList.begin(), IntArgList.end());
3279
3280  return llvm::StructType::get(getVMContext(), ArgList);
3281}
3282
3283llvm::Type *MipsABIInfo::getPaddingType(uint64_t Align, uint64_t Offset) const {
3284  assert((Offset % MinABIStackAlignInBytes) == 0);
3285
3286  if ((Align - 1) & Offset)
3287    return llvm::IntegerType::get(getVMContext(), MinABIStackAlignInBytes * 8);
3288
3289  return 0;
3290}
3291
3292ABIArgInfo
3293MipsABIInfo::classifyArgumentType(QualType Ty, uint64_t &Offset) const {
3294  uint64_t OrigOffset = Offset;
3295  uint64_t TySize = getContext().getTypeSize(Ty);
3296  uint64_t Align = getContext().getTypeAlign(Ty) / 8;
3297
3298  Align = std::min(std::max(Align, (uint64_t)MinABIStackAlignInBytes),
3299                   (uint64_t)StackAlignInBytes);
3300  Offset = llvm::RoundUpToAlignment(Offset, Align);
3301  Offset += llvm::RoundUpToAlignment(TySize, Align * 8) / 8;
3302
3303  if (isAggregateTypeForABI(Ty) || Ty->isVectorType()) {
3304    // Ignore empty aggregates.
3305    if (TySize == 0)
3306      return ABIArgInfo::getIgnore();
3307
3308    // Records with non trivial destructors/constructors should not be passed
3309    // by value.
3310    if (isRecordWithNonTrivialDestructorOrCopyConstructor(Ty)) {
3311      Offset = OrigOffset + MinABIStackAlignInBytes;
3312      return ABIArgInfo::getIndirect(0, /*ByVal=*/false);
3313    }
3314
3315    // If we have reached here, aggregates are passed directly by coercing to
3316    // another structure type. Padding is inserted if the offset of the
3317    // aggregate is unaligned.
3318    return ABIArgInfo::getDirect(HandleAggregates(Ty, TySize), 0,
3319                                 getPaddingType(Align, OrigOffset));
3320  }
3321
3322  // Treat an enum type as its underlying type.
3323  if (const EnumType *EnumTy = Ty->getAs<EnumType>())
3324    Ty = EnumTy->getDecl()->getIntegerType();
3325
3326  if (Ty->isPromotableIntegerType())
3327    return ABIArgInfo::getExtend();
3328
3329  return ABIArgInfo::getDirect(0, 0, getPaddingType(Align, OrigOffset));
3330}
3331
3332llvm::Type*
3333MipsABIInfo::returnAggregateInRegs(QualType RetTy, uint64_t Size) const {
3334  const RecordType *RT = RetTy->getAs<RecordType>();
3335  SmallVector<llvm::Type*, 8> RTList;
3336
3337  if (RT && RT->isStructureOrClassType()) {
3338    const RecordDecl *RD = RT->getDecl();
3339    const ASTRecordLayout &Layout = getContext().getASTRecordLayout(RD);
3340    unsigned FieldCnt = Layout.getFieldCount();
3341
3342    // N32/64 returns struct/classes in floating point registers if the
3343    // following conditions are met:
3344    // 1. The size of the struct/class is no larger than 128-bit.
3345    // 2. The struct/class has one or two fields all of which are floating
3346    //    point types.
3347    // 3. The offset of the first field is zero (this follows what gcc does).
3348    //
3349    // Any other composite results are returned in integer registers.
3350    //
3351    if (FieldCnt && (FieldCnt <= 2) && !Layout.getFieldOffset(0)) {
3352      RecordDecl::field_iterator b = RD->field_begin(), e = RD->field_end();
3353      for (; b != e; ++b) {
3354        const BuiltinType *BT = b->getType()->getAs<BuiltinType>();
3355
3356        if (!BT || !BT->isFloatingPoint())
3357          break;
3358
3359        RTList.push_back(CGT.ConvertType(b->getType()));
3360      }
3361
3362      if (b == e)
3363        return llvm::StructType::get(getVMContext(), RTList,
3364                                     RD->hasAttr<PackedAttr>());
3365
3366      RTList.clear();
3367    }
3368  }
3369
3370  CoerceToIntArgs(Size, RTList);
3371  return llvm::StructType::get(getVMContext(), RTList);
3372}
3373
3374ABIArgInfo MipsABIInfo::classifyReturnType(QualType RetTy) const {
3375  uint64_t Size = getContext().getTypeSize(RetTy);
3376
3377  if (RetTy->isVoidType() || Size == 0)
3378    return ABIArgInfo::getIgnore();
3379
3380  if (isAggregateTypeForABI(RetTy) || RetTy->isVectorType()) {
3381    if (Size <= 128) {
3382      if (RetTy->isAnyComplexType())
3383        return ABIArgInfo::getDirect();
3384
3385      // O32 returns integer vectors in registers.
3386      if (IsO32 && RetTy->isVectorType() && !RetTy->hasFloatingRepresentation())
3387        return ABIArgInfo::getDirect(returnAggregateInRegs(RetTy, Size));
3388
3389      if (!IsO32 && !isRecordWithNonTrivialDestructorOrCopyConstructor(RetTy))
3390        return ABIArgInfo::getDirect(returnAggregateInRegs(RetTy, Size));
3391    }
3392
3393    return ABIArgInfo::getIndirect(0);
3394  }
3395
3396  // Treat an enum type as its underlying type.
3397  if (const EnumType *EnumTy = RetTy->getAs<EnumType>())
3398    RetTy = EnumTy->getDecl()->getIntegerType();
3399
3400  return (RetTy->isPromotableIntegerType() ?
3401          ABIArgInfo::getExtend() : ABIArgInfo::getDirect());
3402}
3403
3404void MipsABIInfo::computeInfo(CGFunctionInfo &FI) const {
3405  ABIArgInfo &RetInfo = FI.getReturnInfo();
3406  RetInfo = classifyReturnType(FI.getReturnType());
3407
3408  // Check if a pointer to an aggregate is passed as a hidden argument.
3409  uint64_t Offset = RetInfo.isIndirect() ? MinABIStackAlignInBytes : 0;
3410
3411  for (CGFunctionInfo::arg_iterator it = FI.arg_begin(), ie = FI.arg_end();
3412       it != ie; ++it)
3413    it->info = classifyArgumentType(it->type, Offset);
3414}
3415
3416llvm::Value* MipsABIInfo::EmitVAArg(llvm::Value *VAListAddr, QualType Ty,
3417                                    CodeGenFunction &CGF) const {
3418  llvm::Type *BP = CGF.Int8PtrTy;
3419  llvm::Type *BPP = CGF.Int8PtrPtrTy;
3420
3421  CGBuilderTy &Builder = CGF.Builder;
3422  llvm::Value *VAListAddrAsBPP = Builder.CreateBitCast(VAListAddr, BPP, "ap");
3423  llvm::Value *Addr = Builder.CreateLoad(VAListAddrAsBPP, "ap.cur");
3424  int64_t TypeAlign = getContext().getTypeAlign(Ty) / 8;
3425  llvm::Type *PTy = llvm::PointerType::getUnqual(CGF.ConvertType(Ty));
3426  llvm::Value *AddrTyped;
3427  unsigned PtrWidth = getContext().getTargetInfo().getPointerWidth(0);
3428  llvm::IntegerType *IntTy = (PtrWidth == 32) ? CGF.Int32Ty : CGF.Int64Ty;
3429
3430  if (TypeAlign > MinABIStackAlignInBytes) {
3431    llvm::Value *AddrAsInt = CGF.Builder.CreatePtrToInt(Addr, IntTy);
3432    llvm::Value *Inc = llvm::ConstantInt::get(IntTy, TypeAlign - 1);
3433    llvm::Value *Mask = llvm::ConstantInt::get(IntTy, -TypeAlign);
3434    llvm::Value *Add = CGF.Builder.CreateAdd(AddrAsInt, Inc);
3435    llvm::Value *And = CGF.Builder.CreateAnd(Add, Mask);
3436    AddrTyped = CGF.Builder.CreateIntToPtr(And, PTy);
3437  }
3438  else
3439    AddrTyped = Builder.CreateBitCast(Addr, PTy);
3440
3441  llvm::Value *AlignedAddr = Builder.CreateBitCast(AddrTyped, BP);
3442  TypeAlign = std::max((unsigned)TypeAlign, MinABIStackAlignInBytes);
3443  uint64_t Offset =
3444    llvm::RoundUpToAlignment(CGF.getContext().getTypeSize(Ty) / 8, TypeAlign);
3445  llvm::Value *NextAddr =
3446    Builder.CreateGEP(AlignedAddr, llvm::ConstantInt::get(IntTy, Offset),
3447                      "ap.next");
3448  Builder.CreateStore(NextAddr, VAListAddrAsBPP);
3449
3450  return AddrTyped;
3451}
3452
3453bool
3454MIPSTargetCodeGenInfo::initDwarfEHRegSizeTable(CodeGen::CodeGenFunction &CGF,
3455                                               llvm::Value *Address) const {
3456  // This information comes from gcc's implementation, which seems to
3457  // as canonical as it gets.
3458
3459  // Everything on MIPS is 4 bytes.  Double-precision FP registers
3460  // are aliased to pairs of single-precision FP registers.
3461  llvm::Value *Four8 = llvm::ConstantInt::get(CGF.Int8Ty, 4);
3462
3463  // 0-31 are the general purpose registers, $0 - $31.
3464  // 32-63 are the floating-point registers, $f0 - $f31.
3465  // 64 and 65 are the multiply/divide registers, $hi and $lo.
3466  // 66 is the (notional, I think) register for signal-handler return.
3467  AssignToArrayRange(CGF.Builder, Address, Four8, 0, 65);
3468
3469  // 67-74 are the floating-point status registers, $fcc0 - $fcc7.
3470  // They are one bit wide and ignored here.
3471
3472  // 80-111 are the coprocessor 0 registers, $c0r0 - $c0r31.
3473  // (coprocessor 1 is the FP unit)
3474  // 112-143 are the coprocessor 2 registers, $c2r0 - $c2r31.
3475  // 144-175 are the coprocessor 3 registers, $c3r0 - $c3r31.
3476  // 176-181 are the DSP accumulator registers.
3477  AssignToArrayRange(CGF.Builder, Address, Four8, 80, 181);
3478  return false;
3479}
3480
3481//===----------------------------------------------------------------------===//
3482// TCE ABI Implementation (see http://tce.cs.tut.fi). Uses mostly the defaults.
3483// Currently subclassed only to implement custom OpenCL C function attribute
3484// handling.
3485//===----------------------------------------------------------------------===//
3486
3487namespace {
3488
3489class TCETargetCodeGenInfo : public DefaultTargetCodeGenInfo {
3490public:
3491  TCETargetCodeGenInfo(CodeGenTypes &CGT)
3492    : DefaultTargetCodeGenInfo(CGT) {}
3493
3494  virtual void SetTargetAttributes(const Decl *D, llvm::GlobalValue *GV,
3495                                   CodeGen::CodeGenModule &M) const;
3496};
3497
3498void TCETargetCodeGenInfo::SetTargetAttributes(const Decl *D,
3499                                               llvm::GlobalValue *GV,
3500                                               CodeGen::CodeGenModule &M) const {
3501  const FunctionDecl *FD = dyn_cast<FunctionDecl>(D);
3502  if (!FD) return;
3503
3504  llvm::Function *F = cast<llvm::Function>(GV);
3505
3506  if (M.getLangOpts().OpenCL) {
3507    if (FD->hasAttr<OpenCLKernelAttr>()) {
3508      // OpenCL C Kernel functions are not subject to inlining
3509      F->addFnAttr(llvm::Attribute::NoInline);
3510
3511      if (FD->hasAttr<ReqdWorkGroupSizeAttr>()) {
3512
3513        // Convert the reqd_work_group_size() attributes to metadata.
3514        llvm::LLVMContext &Context = F->getContext();
3515        llvm::NamedMDNode *OpenCLMetadata =
3516            M.getModule().getOrInsertNamedMetadata("opencl.kernel_wg_size_info");
3517
3518        SmallVector<llvm::Value*, 5> Operands;
3519        Operands.push_back(F);
3520
3521        Operands.push_back(llvm::Constant::getIntegerValue(M.Int32Ty,
3522                             llvm::APInt(32,
3523                             FD->getAttr<ReqdWorkGroupSizeAttr>()->getXDim())));
3524        Operands.push_back(llvm::Constant::getIntegerValue(M.Int32Ty,
3525                             llvm::APInt(32,
3526                               FD->getAttr<ReqdWorkGroupSizeAttr>()->getYDim())));
3527        Operands.push_back(llvm::Constant::getIntegerValue(M.Int32Ty,
3528                             llvm::APInt(32,
3529                               FD->getAttr<ReqdWorkGroupSizeAttr>()->getZDim())));
3530
3531        // Add a boolean constant operand for "required" (true) or "hint" (false)
3532        // for implementing the work_group_size_hint attr later. Currently
3533        // always true as the hint is not yet implemented.
3534        Operands.push_back(llvm::ConstantInt::getTrue(Context));
3535        OpenCLMetadata->addOperand(llvm::MDNode::get(Context, Operands));
3536      }
3537    }
3538  }
3539}
3540
3541}
3542
3543//===----------------------------------------------------------------------===//
3544// Hexagon ABI Implementation
3545//===----------------------------------------------------------------------===//
3546
3547namespace {
3548
3549class HexagonABIInfo : public ABIInfo {
3550
3551
3552public:
3553  HexagonABIInfo(CodeGenTypes &CGT) : ABIInfo(CGT) {}
3554
3555private:
3556
3557  ABIArgInfo classifyReturnType(QualType RetTy) const;
3558  ABIArgInfo classifyArgumentType(QualType RetTy) const;
3559
3560  virtual void computeInfo(CGFunctionInfo &FI) const;
3561
3562  virtual llvm::Value *EmitVAArg(llvm::Value *VAListAddr, QualType Ty,
3563                                 CodeGenFunction &CGF) const;
3564};
3565
3566class HexagonTargetCodeGenInfo : public TargetCodeGenInfo {
3567public:
3568  HexagonTargetCodeGenInfo(CodeGenTypes &CGT)
3569    :TargetCodeGenInfo(new HexagonABIInfo(CGT)) {}
3570
3571  int getDwarfEHStackPointer(CodeGen::CodeGenModule &M) const {
3572    return 29;
3573  }
3574};
3575
3576}
3577
3578void HexagonABIInfo::computeInfo(CGFunctionInfo &FI) const {
3579  FI.getReturnInfo() = classifyReturnType(FI.getReturnType());
3580  for (CGFunctionInfo::arg_iterator it = FI.arg_begin(), ie = FI.arg_end();
3581       it != ie; ++it)
3582    it->info = classifyArgumentType(it->type);
3583}
3584
3585ABIArgInfo HexagonABIInfo::classifyArgumentType(QualType Ty) const {
3586  if (!isAggregateTypeForABI(Ty)) {
3587    // Treat an enum type as its underlying type.
3588    if (const EnumType *EnumTy = Ty->getAs<EnumType>())
3589      Ty = EnumTy->getDecl()->getIntegerType();
3590
3591    return (Ty->isPromotableIntegerType() ?
3592            ABIArgInfo::getExtend() : ABIArgInfo::getDirect());
3593  }
3594
3595  // Ignore empty records.
3596  if (isEmptyRecord(getContext(), Ty, true))
3597    return ABIArgInfo::getIgnore();
3598
3599  // Structures with either a non-trivial destructor or a non-trivial
3600  // copy constructor are always indirect.
3601  if (isRecordWithNonTrivialDestructorOrCopyConstructor(Ty))
3602    return ABIArgInfo::getIndirect(0, /*ByVal=*/false);
3603
3604  uint64_t Size = getContext().getTypeSize(Ty);
3605  if (Size > 64)
3606    return ABIArgInfo::getIndirect(0, /*ByVal=*/true);
3607    // Pass in the smallest viable integer type.
3608  else if (Size > 32)
3609      return ABIArgInfo::getDirect(llvm::Type::getInt64Ty(getVMContext()));
3610  else if (Size > 16)
3611      return ABIArgInfo::getDirect(llvm::Type::getInt32Ty(getVMContext()));
3612  else if (Size > 8)
3613      return ABIArgInfo::getDirect(llvm::Type::getInt16Ty(getVMContext()));
3614  else
3615      return ABIArgInfo::getDirect(llvm::Type::getInt8Ty(getVMContext()));
3616}
3617
3618ABIArgInfo HexagonABIInfo::classifyReturnType(QualType RetTy) const {
3619  if (RetTy->isVoidType())
3620    return ABIArgInfo::getIgnore();
3621
3622  // Large vector types should be returned via memory.
3623  if (RetTy->isVectorType() && getContext().getTypeSize(RetTy) > 64)
3624    return ABIArgInfo::getIndirect(0);
3625
3626  if (!isAggregateTypeForABI(RetTy)) {
3627    // Treat an enum type as its underlying type.
3628    if (const EnumType *EnumTy = RetTy->getAs<EnumType>())
3629      RetTy = EnumTy->getDecl()->getIntegerType();
3630
3631    return (RetTy->isPromotableIntegerType() ?
3632            ABIArgInfo::getExtend() : ABIArgInfo::getDirect());
3633  }
3634
3635  // Structures with either a non-trivial destructor or a non-trivial
3636  // copy constructor are always indirect.
3637  if (isRecordWithNonTrivialDestructorOrCopyConstructor(RetTy))
3638    return ABIArgInfo::getIndirect(0, /*ByVal=*/false);
3639
3640  if (isEmptyRecord(getContext(), RetTy, true))
3641    return ABIArgInfo::getIgnore();
3642
3643  // Aggregates <= 8 bytes are returned in r0; other aggregates
3644  // are returned indirectly.
3645  uint64_t Size = getContext().getTypeSize(RetTy);
3646  if (Size <= 64) {
3647    // Return in the smallest viable integer type.
3648    if (Size <= 8)
3649      return ABIArgInfo::getDirect(llvm::Type::getInt8Ty(getVMContext()));
3650    if (Size <= 16)
3651      return ABIArgInfo::getDirect(llvm::Type::getInt16Ty(getVMContext()));
3652    if (Size <= 32)
3653      return ABIArgInfo::getDirect(llvm::Type::getInt32Ty(getVMContext()));
3654    return ABIArgInfo::getDirect(llvm::Type::getInt64Ty(getVMContext()));
3655  }
3656
3657  return ABIArgInfo::getIndirect(0, /*ByVal=*/true);
3658}
3659
3660llvm::Value *HexagonABIInfo::EmitVAArg(llvm::Value *VAListAddr, QualType Ty,
3661                                       CodeGenFunction &CGF) const {
3662  // FIXME: Need to handle alignment
3663  llvm::Type *BPP = CGF.Int8PtrPtrTy;
3664
3665  CGBuilderTy &Builder = CGF.Builder;
3666  llvm::Value *VAListAddrAsBPP = Builder.CreateBitCast(VAListAddr, BPP,
3667                                                       "ap");
3668  llvm::Value *Addr = Builder.CreateLoad(VAListAddrAsBPP, "ap.cur");
3669  llvm::Type *PTy =
3670    llvm::PointerType::getUnqual(CGF.ConvertType(Ty));
3671  llvm::Value *AddrTyped = Builder.CreateBitCast(Addr, PTy);
3672
3673  uint64_t Offset =
3674    llvm::RoundUpToAlignment(CGF.getContext().getTypeSize(Ty) / 8, 4);
3675  llvm::Value *NextAddr =
3676    Builder.CreateGEP(Addr, llvm::ConstantInt::get(CGF.Int32Ty, Offset),
3677                      "ap.next");
3678  Builder.CreateStore(NextAddr, VAListAddrAsBPP);
3679
3680  return AddrTyped;
3681}
3682
3683
3684const TargetCodeGenInfo &CodeGenModule::getTargetCodeGenInfo() {
3685  if (TheTargetCodeGenInfo)
3686    return *TheTargetCodeGenInfo;
3687
3688  const llvm::Triple &Triple = getContext().getTargetInfo().getTriple();
3689  switch (Triple.getArch()) {
3690  default:
3691    return *(TheTargetCodeGenInfo = new DefaultTargetCodeGenInfo(Types));
3692
3693  case llvm::Triple::mips:
3694  case llvm::Triple::mipsel:
3695    return *(TheTargetCodeGenInfo = new MIPSTargetCodeGenInfo(Types, true));
3696
3697  case llvm::Triple::mips64:
3698  case llvm::Triple::mips64el:
3699    return *(TheTargetCodeGenInfo = new MIPSTargetCodeGenInfo(Types, false));
3700
3701  case llvm::Triple::arm:
3702  case llvm::Triple::thumb:
3703    {
3704      ARMABIInfo::ABIKind Kind = ARMABIInfo::AAPCS;
3705
3706      if (strcmp(getContext().getTargetInfo().getABI(), "apcs-gnu") == 0)
3707        Kind = ARMABIInfo::APCS;
3708      else if (CodeGenOpts.FloatABI == "hard")
3709        Kind = ARMABIInfo::AAPCS_VFP;
3710
3711      return *(TheTargetCodeGenInfo = new ARMTargetCodeGenInfo(Types, Kind));
3712    }
3713
3714  case llvm::Triple::ppc:
3715    return *(TheTargetCodeGenInfo = new PPC32TargetCodeGenInfo(Types));
3716  case llvm::Triple::ppc64:
3717    return *(TheTargetCodeGenInfo = new PPC64TargetCodeGenInfo(Types));
3718
3719  case llvm::Triple::nvptx:
3720  case llvm::Triple::nvptx64:
3721    return *(TheTargetCodeGenInfo = new NVPTXTargetCodeGenInfo(Types));
3722
3723  case llvm::Triple::mblaze:
3724    return *(TheTargetCodeGenInfo = new MBlazeTargetCodeGenInfo(Types));
3725
3726  case llvm::Triple::msp430:
3727    return *(TheTargetCodeGenInfo = new MSP430TargetCodeGenInfo(Types));
3728
3729  case llvm::Triple::tce:
3730    return *(TheTargetCodeGenInfo = new TCETargetCodeGenInfo(Types));
3731
3732  case llvm::Triple::x86: {
3733    bool DisableMMX = strcmp(getContext().getTargetInfo().getABI(), "no-mmx") == 0;
3734
3735    if (Triple.isOSDarwin())
3736      return *(TheTargetCodeGenInfo =
3737               new X86_32TargetCodeGenInfo(
3738                 Types, true, true, DisableMMX, false));
3739
3740    switch (Triple.getOS()) {
3741    case llvm::Triple::Cygwin:
3742    case llvm::Triple::MinGW32:
3743    case llvm::Triple::AuroraUX:
3744    case llvm::Triple::DragonFly:
3745    case llvm::Triple::FreeBSD:
3746    case llvm::Triple::OpenBSD:
3747      return *(TheTargetCodeGenInfo =
3748               new X86_32TargetCodeGenInfo(
3749                 Types, false, true, DisableMMX, false));
3750
3751    case llvm::Triple::Win32:
3752      return *(TheTargetCodeGenInfo =
3753               new X86_32TargetCodeGenInfo(
3754                 Types, false, true, DisableMMX, true));
3755
3756    default:
3757      return *(TheTargetCodeGenInfo =
3758               new X86_32TargetCodeGenInfo(
3759                 Types, false, false, DisableMMX, false));
3760    }
3761  }
3762
3763  case llvm::Triple::x86_64: {
3764    bool HasAVX = strcmp(getContext().getTargetInfo().getABI(), "avx") == 0;
3765
3766    switch (Triple.getOS()) {
3767    case llvm::Triple::Win32:
3768    case llvm::Triple::MinGW32:
3769    case llvm::Triple::Cygwin:
3770      return *(TheTargetCodeGenInfo = new WinX86_64TargetCodeGenInfo(Types));
3771    default:
3772      return *(TheTargetCodeGenInfo = new X86_64TargetCodeGenInfo(Types,
3773                                                                  HasAVX));
3774    }
3775  }
3776  case llvm::Triple::hexagon:
3777    return *(TheTargetCodeGenInfo = new HexagonTargetCodeGenInfo(Types));
3778  }
3779}
3780