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