CGCXX.cpp revision f9a883c27e3b5724a5a59499691fa109eb5032f8 
1//===--- CGDecl.cpp - Emit LLVM Code for declarations ---------------------===//
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// This contains code dealing with C++ code generation.
11//
12//===----------------------------------------------------------------------===//
13
14// We might split this into multiple files if it gets too unwieldy
15
16#include "CodeGenFunction.h"
17#include "CodeGenModule.h"
18#include "Mangle.h"
19#include "clang/AST/ASTContext.h"
20#include "clang/AST/RecordLayout.h"
21#include "clang/AST/Decl.h"
22#include "clang/AST/DeclCXX.h"
23#include "clang/AST/DeclObjC.h"
24#include "llvm/ADT/StringExtras.h"
25using namespace clang;
26using namespace CodeGen;
27
28void
29CodeGenFunction::EmitCXXGlobalDtorRegistration(const CXXDestructorDecl *Dtor,
30                                               llvm::Constant *DeclPtr) {
31  // FIXME: This is ABI dependent and we use the Itanium ABI.
32
33  const llvm::Type *Int8PtrTy =
34    llvm::PointerType::getUnqual(llvm::Type::getInt8Ty(VMContext));
35
36  std::vector<const llvm::Type *> Params;
37  Params.push_back(Int8PtrTy);
38
39  // Get the destructor function type
40  const llvm::Type *DtorFnTy =
41    llvm::FunctionType::get(llvm::Type::getVoidTy(VMContext), Params, false);
42  DtorFnTy = llvm::PointerType::getUnqual(DtorFnTy);
43
44  Params.clear();
45  Params.push_back(DtorFnTy);
46  Params.push_back(Int8PtrTy);
47  Params.push_back(Int8PtrTy);
48
49  // Get the __cxa_atexit function type
50  // extern "C" int __cxa_atexit ( void (*f)(void *), void *p, void *d );
51  const llvm::FunctionType *AtExitFnTy =
52    llvm::FunctionType::get(ConvertType(getContext().IntTy), Params, false);
53
54  llvm::Constant *AtExitFn = CGM.CreateRuntimeFunction(AtExitFnTy,
55                                                       "__cxa_atexit");
56
57  llvm::Constant *Handle = CGM.CreateRuntimeVariable(Int8PtrTy,
58                                                     "__dso_handle");
59
60  llvm::Constant *DtorFn = CGM.GetAddrOfCXXDestructor(Dtor, Dtor_Complete);
61
62  llvm::Value *Args[3] = { llvm::ConstantExpr::getBitCast(DtorFn, DtorFnTy),
63                           llvm::ConstantExpr::getBitCast(DeclPtr, Int8PtrTy),
64                           llvm::ConstantExpr::getBitCast(Handle, Int8PtrTy) };
65  Builder.CreateCall(AtExitFn, &Args[0], llvm::array_endof(Args));
66}
67
68void CodeGenFunction::EmitCXXGlobalVarDeclInit(const VarDecl &D,
69                                               llvm::Constant *DeclPtr) {
70  assert(D.hasGlobalStorage() &&
71         "VarDecl must have global storage!");
72
73  const Expr *Init = D.getInit();
74  QualType T = D.getType();
75
76  if (T->isReferenceType()) {
77    ErrorUnsupported(Init, "global variable that binds to a reference");
78  } else if (!hasAggregateLLVMType(T)) {
79    llvm::Value *V = EmitScalarExpr(Init);
80    EmitStoreOfScalar(V, DeclPtr, T.isVolatileQualified(), T);
81  } else if (T->isAnyComplexType()) {
82    EmitComplexExprIntoAddr(Init, DeclPtr, T.isVolatileQualified());
83  } else {
84    EmitAggExpr(Init, DeclPtr, T.isVolatileQualified());
85
86    if (const RecordType *RT = T->getAs<RecordType>()) {
87      CXXRecordDecl *RD = cast<CXXRecordDecl>(RT->getDecl());
88      if (!RD->hasTrivialDestructor())
89        EmitCXXGlobalDtorRegistration(RD->getDestructor(getContext()), DeclPtr);
90    }
91  }
92}
93
94void
95CodeGenModule::EmitCXXGlobalInitFunc() {
96  if (CXXGlobalInits.empty())
97    return;
98
99  const llvm::FunctionType *FTy = llvm::FunctionType::get(llvm::Type::getVoidTy(VMContext),
100                                                          false);
101
102  // Create our global initialization function.
103  // FIXME: Should this be tweakable by targets?
104  llvm::Function *Fn =
105    llvm::Function::Create(FTy, llvm::GlobalValue::InternalLinkage,
106                           "__cxx_global_initialization", &TheModule);
107
108  CodeGenFunction(*this).GenerateCXXGlobalInitFunc(Fn,
109                                                   &CXXGlobalInits[0],
110                                                   CXXGlobalInits.size());
111  AddGlobalCtor(Fn);
112}
113
114void CodeGenFunction::GenerateCXXGlobalInitFunc(llvm::Function *Fn,
115                                                const VarDecl **Decls,
116                                                unsigned NumDecls) {
117  StartFunction(0, getContext().VoidTy, Fn, FunctionArgList(),
118                SourceLocation());
119
120  for (unsigned i = 0; i != NumDecls; ++i) {
121    const VarDecl *D = Decls[i];
122
123    llvm::Constant *DeclPtr = CGM.GetAddrOfGlobalVar(D);
124    EmitCXXGlobalVarDeclInit(*D, DeclPtr);
125  }
126  FinishFunction();
127}
128
129void
130CodeGenFunction::EmitStaticCXXBlockVarDeclInit(const VarDecl &D,
131                                               llvm::GlobalVariable *GV) {
132  // FIXME: This should use __cxa_guard_{acquire,release}?
133
134  assert(!getContext().getLangOptions().ThreadsafeStatics &&
135         "thread safe statics are currently not supported!");
136
137  llvm::SmallString<256> GuardVName;
138  llvm::raw_svector_ostream GuardVOut(GuardVName);
139  mangleGuardVariable(&D, getContext(), GuardVOut);
140
141  // Create the guard variable.
142  llvm::GlobalValue *GuardV =
143    new llvm::GlobalVariable(CGM.getModule(), llvm::Type::getInt64Ty(VMContext), false,
144                             GV->getLinkage(),
145                             llvm::Constant::getNullValue(llvm::Type::getInt64Ty(VMContext)),
146                             GuardVName.str());
147
148  // Load the first byte of the guard variable.
149  const llvm::Type *PtrTy = llvm::PointerType::get(llvm::Type::getInt8Ty(VMContext), 0);
150  llvm::Value *V = Builder.CreateLoad(Builder.CreateBitCast(GuardV, PtrTy),
151                                      "tmp");
152
153  // Compare it against 0.
154  llvm::Value *nullValue = llvm::Constant::getNullValue(llvm::Type::getInt8Ty(VMContext));
155  llvm::Value *ICmp = Builder.CreateICmpEQ(V, nullValue , "tobool");
156
157  llvm::BasicBlock *InitBlock = createBasicBlock("init");
158  llvm::BasicBlock *EndBlock = createBasicBlock("init.end");
159
160  // If the guard variable is 0, jump to the initializer code.
161  Builder.CreateCondBr(ICmp, InitBlock, EndBlock);
162
163  EmitBlock(InitBlock);
164
165  EmitCXXGlobalVarDeclInit(D, GV);
166
167  Builder.CreateStore(llvm::ConstantInt::get(llvm::Type::getInt8Ty(VMContext), 1),
168                      Builder.CreateBitCast(GuardV, PtrTy));
169
170  EmitBlock(EndBlock);
171}
172
173RValue CodeGenFunction::EmitCXXMemberCall(const CXXMethodDecl *MD,
174                                          llvm::Value *Callee,
175                                          llvm::Value *This,
176                                          CallExpr::const_arg_iterator ArgBeg,
177                                          CallExpr::const_arg_iterator ArgEnd) {
178  assert(MD->isInstance() &&
179         "Trying to emit a member call expr on a static method!");
180
181  const FunctionProtoType *FPT = MD->getType()->getAsFunctionProtoType();
182
183  CallArgList Args;
184
185  // Push the this ptr.
186  Args.push_back(std::make_pair(RValue::get(This),
187                                MD->getThisType(getContext())));
188
189  // And the rest of the call args
190  EmitCallArgs(Args, FPT, ArgBeg, ArgEnd);
191
192  QualType ResultType = MD->getType()->getAsFunctionType()->getResultType();
193  return EmitCall(CGM.getTypes().getFunctionInfo(ResultType, Args),
194                  Callee, Args, MD);
195}
196
197RValue CodeGenFunction::EmitCXXMemberCallExpr(const CXXMemberCallExpr *CE) {
198  const MemberExpr *ME = cast<MemberExpr>(CE->getCallee());
199  const CXXMethodDecl *MD = cast<CXXMethodDecl>(ME->getMemberDecl());
200
201  const FunctionProtoType *FPT = MD->getType()->getAsFunctionProtoType();
202
203  const llvm::Type *Ty =
204    CGM.getTypes().GetFunctionType(CGM.getTypes().getFunctionInfo(MD),
205                                   FPT->isVariadic());
206  llvm::Value *This;
207
208  if (ME->isArrow())
209    This = EmitScalarExpr(ME->getBase());
210  else {
211    LValue BaseLV = EmitLValue(ME->getBase());
212    This = BaseLV.getAddress();
213  }
214
215  // C++ [class.virtual]p12:
216  //   Explicit qualification with the scope operator (5.1) suppresses the
217  //   virtual call mechanism.
218  llvm::Value *Callee;
219  if (MD->isVirtual() && !ME->hasQualifier())
220    Callee = BuildVirtualCall(MD, This, Ty);
221  else
222    Callee = CGM.GetAddrOfFunction(GlobalDecl(MD), Ty);
223
224  return EmitCXXMemberCall(MD, Callee, This,
225                           CE->arg_begin(), CE->arg_end());
226}
227
228RValue
229CodeGenFunction::EmitCXXOperatorMemberCallExpr(const CXXOperatorCallExpr *E,
230                                               const CXXMethodDecl *MD) {
231  assert(MD->isInstance() &&
232         "Trying to emit a member call expr on a static method!");
233
234  if (MD->isCopyAssignment()) {
235    const CXXRecordDecl *ClassDecl = cast<CXXRecordDecl>(MD->getDeclContext());
236    if (ClassDecl->hasTrivialCopyAssignment()) {
237      assert(!ClassDecl->hasUserDeclaredCopyAssignment() &&
238             "EmitCXXOperatorMemberCallExpr - user declared copy assignment");
239      llvm::Value *This = EmitLValue(E->getArg(0)).getAddress();
240      llvm::Value *Src = EmitLValue(E->getArg(1)).getAddress();
241      QualType Ty = E->getType();
242      EmitAggregateCopy(This, Src, Ty);
243      return RValue::get(This);
244    }
245  }
246
247  const FunctionProtoType *FPT = MD->getType()->getAsFunctionProtoType();
248  const llvm::Type *Ty =
249  CGM.getTypes().GetFunctionType(CGM.getTypes().getFunctionInfo(MD),
250                                 FPT->isVariadic());
251  llvm::Constant *Callee = CGM.GetAddrOfFunction(GlobalDecl(MD), Ty);
252
253  llvm::Value *This = EmitLValue(E->getArg(0)).getAddress();
254
255  return EmitCXXMemberCall(MD, Callee, This,
256                           E->arg_begin() + 1, E->arg_end());
257}
258
259RValue
260CodeGenFunction::EmitCXXFunctionalCastExpr(const CXXFunctionalCastExpr *E) {
261  assert((E->getCastKind() == CastExpr::CK_UserDefinedConversion) &&
262         "EmitCXXFunctionalCastExpr - called with wrong cast");
263
264  CXXMethodDecl *MD = E->getTypeConversionMethod();
265  assert(MD && "EmitCXXFunctionalCastExpr - null conversion method");
266  assert(isa<CXXConversionDecl>(MD) && "EmitCXXFunctionalCastExpr - not"
267         " method decl");
268  const FunctionProtoType *FPT = MD->getType()->getAsFunctionProtoType();
269
270  const llvm::Type *Ty =
271    CGM.getTypes().GetFunctionType(CGM.getTypes().getFunctionInfo(MD),
272                                   FPT->isVariadic());
273  llvm::Constant *Callee = CGM.GetAddrOfFunction(GlobalDecl(MD), Ty);
274  llvm::Value *This = EmitLValue(E->getSubExpr()).getAddress();
275  RValue RV = EmitCXXMemberCall(MD, Callee, This, 0, 0);
276  if (RV.isAggregate())
277    RV = RValue::get(RV.getAggregateAddr());
278  return RV;
279}
280
281llvm::Value *CodeGenFunction::LoadCXXThis() {
282  assert(isa<CXXMethodDecl>(CurFuncDecl) &&
283         "Must be in a C++ member function decl to load 'this'");
284  assert(cast<CXXMethodDecl>(CurFuncDecl)->isInstance() &&
285         "Must be in a C++ member function decl to load 'this'");
286
287  // FIXME: What if we're inside a block?
288  // ans: See how CodeGenFunction::LoadObjCSelf() uses
289  // CodeGenFunction::BlockForwardSelf() for how to do this.
290  return Builder.CreateLoad(LocalDeclMap[CXXThisDecl], "this");
291}
292
293static bool
294GetNestedPaths(llvm::SmallVectorImpl<const CXXRecordDecl *> &NestedBasePaths,
295               const CXXRecordDecl *ClassDecl,
296               const CXXRecordDecl *BaseClassDecl) {
297  for (CXXRecordDecl::base_class_const_iterator i = ClassDecl->bases_begin(),
298      e = ClassDecl->bases_end(); i != e; ++i) {
299    if (i->isVirtual())
300      continue;
301    const CXXRecordDecl *Base =
302      cast<CXXRecordDecl>(i->getType()->getAs<RecordType>()->getDecl());
303    if (Base == BaseClassDecl) {
304      NestedBasePaths.push_back(BaseClassDecl);
305      return true;
306    }
307  }
308  // BaseClassDecl not an immediate base of ClassDecl.
309  for (CXXRecordDecl::base_class_const_iterator i = ClassDecl->bases_begin(),
310       e = ClassDecl->bases_end(); i != e; ++i) {
311    if (i->isVirtual())
312      continue;
313    const CXXRecordDecl *Base =
314      cast<CXXRecordDecl>(i->getType()->getAs<RecordType>()->getDecl());
315    if (GetNestedPaths(NestedBasePaths, Base, BaseClassDecl)) {
316      NestedBasePaths.push_back(Base);
317      return true;
318    }
319  }
320  return false;
321}
322
323llvm::Value *CodeGenFunction::AddressCXXOfBaseClass(llvm::Value *BaseValue,
324                                          const CXXRecordDecl *ClassDecl,
325                                          const CXXRecordDecl *BaseClassDecl) {
326  if (ClassDecl == BaseClassDecl)
327    return BaseValue;
328
329  llvm::Type *I8Ptr = llvm::PointerType::getUnqual(llvm::Type::getInt8Ty(VMContext));
330  llvm::SmallVector<const CXXRecordDecl *, 16> NestedBasePaths;
331  GetNestedPaths(NestedBasePaths, ClassDecl, BaseClassDecl);
332  assert(NestedBasePaths.size() > 0 &&
333         "AddressCXXOfBaseClass - inheritence path failed");
334  NestedBasePaths.push_back(ClassDecl);
335  uint64_t Offset = 0;
336
337  // Accessing a member of the base class. Must add delata to
338  // the load of 'this'.
339  for (unsigned i = NestedBasePaths.size()-1; i > 0; i--) {
340    const CXXRecordDecl *DerivedClass = NestedBasePaths[i];
341    const CXXRecordDecl *BaseClass = NestedBasePaths[i-1];
342    const ASTRecordLayout &Layout =
343      getContext().getASTRecordLayout(DerivedClass);
344    Offset += Layout.getBaseClassOffset(BaseClass) / 8;
345  }
346  llvm::Value *OffsetVal =
347    llvm::ConstantInt::get(
348                  CGM.getTypes().ConvertType(CGM.getContext().LongTy), Offset);
349  BaseValue = Builder.CreateBitCast(BaseValue, I8Ptr);
350  BaseValue = Builder.CreateGEP(BaseValue, OffsetVal, "add.ptr");
351  QualType BTy =
352    getContext().getCanonicalType(
353      getContext().getTypeDeclType(const_cast<CXXRecordDecl*>(BaseClassDecl)));
354  const llvm::Type *BasePtr = ConvertType(BTy);
355  BasePtr = llvm::PointerType::getUnqual(BasePtr);
356  BaseValue = Builder.CreateBitCast(BaseValue, BasePtr);
357  return BaseValue;
358}
359
360/// EmitCXXAggrConstructorCall - This routine essentially creates a (nested)
361/// for-loop to call the default constructor on individual members of the
362/// array. 'Array' is the array type, 'This' is llvm pointer of the start
363/// of the array and 'D' is the default costructor Decl for elements of the
364/// array. It is assumed that all relevant checks have been made by the
365/// caller.
366void
367CodeGenFunction::EmitCXXAggrConstructorCall(const CXXConstructorDecl *D,
368                                            const ArrayType *Array,
369                                            llvm::Value *This) {
370  const ConstantArrayType *CA = dyn_cast<ConstantArrayType>(Array);
371  assert(CA && "Do we support VLA for construction ?");
372
373  // Create a temporary for the loop index and initialize it with 0.
374  llvm::Value *IndexPtr = CreateTempAlloca(llvm::Type::getInt64Ty(VMContext),
375                                           "loop.index");
376  llvm::Value* zeroConstant =
377    llvm::Constant::getNullValue(llvm::Type::getInt64Ty(VMContext));
378  Builder.CreateStore(zeroConstant, IndexPtr, false);
379
380  // Start the loop with a block that tests the condition.
381  llvm::BasicBlock *CondBlock = createBasicBlock("for.cond");
382  llvm::BasicBlock *AfterFor = createBasicBlock("for.end");
383
384  EmitBlock(CondBlock);
385
386  llvm::BasicBlock *ForBody = createBasicBlock("for.body");
387
388  // Generate: if (loop-index < number-of-elements fall to the loop body,
389  // otherwise, go to the block after the for-loop.
390  uint64_t NumElements = getContext().getConstantArrayElementCount(CA);
391  llvm::Value * NumElementsPtr =
392    llvm::ConstantInt::get(llvm::Type::getInt64Ty(VMContext), NumElements);
393  llvm::Value *Counter = Builder.CreateLoad(IndexPtr);
394  llvm::Value *IsLess = Builder.CreateICmpULT(Counter, NumElementsPtr,
395                                              "isless");
396  // If the condition is true, execute the body.
397  Builder.CreateCondBr(IsLess, ForBody, AfterFor);
398
399  EmitBlock(ForBody);
400
401  llvm::BasicBlock *ContinueBlock = createBasicBlock("for.inc");
402  // Inside the loop body, emit the constructor call on the array element.
403  Counter = Builder.CreateLoad(IndexPtr);
404  llvm::Value *Address = Builder.CreateInBoundsGEP(This, Counter, "arrayidx");
405  EmitCXXConstructorCall(D, Ctor_Complete, Address, 0, 0);
406
407  EmitBlock(ContinueBlock);
408
409  // Emit the increment of the loop counter.
410  llvm::Value *NextVal = llvm::ConstantInt::get(Counter->getType(), 1);
411  Counter = Builder.CreateLoad(IndexPtr);
412  NextVal = Builder.CreateAdd(Counter, NextVal, "inc");
413  Builder.CreateStore(NextVal, IndexPtr, false);
414
415  // Finally, branch back up to the condition for the next iteration.
416  EmitBranch(CondBlock);
417
418  // Emit the fall-through block.
419  EmitBlock(AfterFor, true);
420}
421
422/// EmitCXXAggrDestructorCall - calls the default destructor on array
423/// elements in reverse order of construction.
424void
425CodeGenFunction::EmitCXXAggrDestructorCall(const CXXDestructorDecl *D,
426                                           const ArrayType *Array,
427                                           llvm::Value *This) {
428  const ConstantArrayType *CA = dyn_cast<ConstantArrayType>(Array);
429  assert(CA && "Do we support VLA for destruction ?");
430  llvm::Value *One = llvm::ConstantInt::get(llvm::Type::getInt64Ty(VMContext),
431                                            1);
432  uint64_t ElementCount = getContext().getConstantArrayElementCount(CA);
433  // Create a temporary for the loop index and initialize it with count of
434  // array elements.
435  llvm::Value *IndexPtr = CreateTempAlloca(llvm::Type::getInt64Ty(VMContext),
436                                           "loop.index");
437  // Index = ElementCount;
438  llvm::Value* UpperCount =
439    llvm::ConstantInt::get(llvm::Type::getInt64Ty(VMContext), ElementCount);
440  Builder.CreateStore(UpperCount, IndexPtr, false);
441
442  // Start the loop with a block that tests the condition.
443  llvm::BasicBlock *CondBlock = createBasicBlock("for.cond");
444  llvm::BasicBlock *AfterFor = createBasicBlock("for.end");
445
446  EmitBlock(CondBlock);
447
448  llvm::BasicBlock *ForBody = createBasicBlock("for.body");
449
450  // Generate: if (loop-index != 0 fall to the loop body,
451  // otherwise, go to the block after the for-loop.
452  llvm::Value* zeroConstant =
453    llvm::Constant::getNullValue(llvm::Type::getInt64Ty(VMContext));
454  llvm::Value *Counter = Builder.CreateLoad(IndexPtr);
455  llvm::Value *IsNE = Builder.CreateICmpNE(Counter, zeroConstant,
456                                            "isne");
457  // If the condition is true, execute the body.
458  Builder.CreateCondBr(IsNE, ForBody, AfterFor);
459
460  EmitBlock(ForBody);
461
462  llvm::BasicBlock *ContinueBlock = createBasicBlock("for.inc");
463  // Inside the loop body, emit the constructor call on the array element.
464  Counter = Builder.CreateLoad(IndexPtr);
465  Counter = Builder.CreateSub(Counter, One);
466  llvm::Value *Address = Builder.CreateInBoundsGEP(This, Counter, "arrayidx");
467  EmitCXXDestructorCall(D, Dtor_Complete, Address);
468
469  EmitBlock(ContinueBlock);
470
471  // Emit the decrement of the loop counter.
472  Counter = Builder.CreateLoad(IndexPtr);
473  Counter = Builder.CreateSub(Counter, One, "dec");
474  Builder.CreateStore(Counter, IndexPtr, false);
475
476  // Finally, branch back up to the condition for the next iteration.
477  EmitBranch(CondBlock);
478
479  // Emit the fall-through block.
480  EmitBlock(AfterFor, true);
481}
482
483void
484CodeGenFunction::EmitCXXConstructorCall(const CXXConstructorDecl *D,
485                                        CXXCtorType Type,
486                                        llvm::Value *This,
487                                        CallExpr::const_arg_iterator ArgBeg,
488                                        CallExpr::const_arg_iterator ArgEnd) {
489  if (D->isCopyConstructor(getContext())) {
490    const CXXRecordDecl *ClassDecl = cast<CXXRecordDecl>(D->getDeclContext());
491    if (ClassDecl->hasTrivialCopyConstructor()) {
492      assert(!ClassDecl->hasUserDeclaredCopyConstructor() &&
493             "EmitCXXConstructorCall - user declared copy constructor");
494      const Expr *E = (*ArgBeg);
495      QualType Ty = E->getType();
496      llvm::Value *Src = EmitLValue(E).getAddress();
497      EmitAggregateCopy(This, Src, Ty);
498      return;
499    }
500  }
501
502  llvm::Value *Callee = CGM.GetAddrOfCXXConstructor(D, Type);
503
504  EmitCXXMemberCall(D, Callee, This, ArgBeg, ArgEnd);
505}
506
507void CodeGenFunction::EmitCXXDestructorCall(const CXXDestructorDecl *D,
508                                            CXXDtorType Type,
509                                            llvm::Value *This) {
510  llvm::Value *Callee = CGM.GetAddrOfCXXDestructor(D, Type);
511
512  EmitCXXMemberCall(D, Callee, This, 0, 0);
513}
514
515void
516CodeGenFunction::EmitCXXConstructExpr(llvm::Value *Dest,
517                                      const CXXConstructExpr *E) {
518  assert(Dest && "Must have a destination!");
519
520  const CXXRecordDecl *RD =
521  cast<CXXRecordDecl>(E->getType()->getAs<RecordType>()->getDecl());
522  if (RD->hasTrivialConstructor())
523    return;
524
525  // Code gen optimization to eliminate copy constructor and return
526  // its first argument instead.
527  if (getContext().getLangOptions().ElideConstructors && E->isElidable()) {
528    CXXConstructExpr::const_arg_iterator i = E->arg_begin();
529    EmitAggExpr((*i), Dest, false);
530    return;
531  }
532  // Call the constructor.
533  EmitCXXConstructorCall(E->getConstructor(), Ctor_Complete, Dest,
534                         E->arg_begin(), E->arg_end());
535}
536
537llvm::Value *CodeGenFunction::EmitCXXNewExpr(const CXXNewExpr *E) {
538  if (E->isArray()) {
539    ErrorUnsupported(E, "new[] expression");
540    return llvm::UndefValue::get(ConvertType(E->getType()));
541  }
542
543  QualType AllocType = E->getAllocatedType();
544  FunctionDecl *NewFD = E->getOperatorNew();
545  const FunctionProtoType *NewFTy = NewFD->getType()->getAsFunctionProtoType();
546
547  CallArgList NewArgs;
548
549  // The allocation size is the first argument.
550  QualType SizeTy = getContext().getSizeType();
551  llvm::Value *AllocSize =
552    llvm::ConstantInt::get(ConvertType(SizeTy),
553                           getContext().getTypeSize(AllocType) / 8);
554
555  NewArgs.push_back(std::make_pair(RValue::get(AllocSize), SizeTy));
556
557  // Emit the rest of the arguments.
558  // FIXME: Ideally, this should just use EmitCallArgs.
559  CXXNewExpr::const_arg_iterator NewArg = E->placement_arg_begin();
560
561  // First, use the types from the function type.
562  // We start at 1 here because the first argument (the allocation size)
563  // has already been emitted.
564  for (unsigned i = 1, e = NewFTy->getNumArgs(); i != e; ++i, ++NewArg) {
565    QualType ArgType = NewFTy->getArgType(i);
566
567    assert(getContext().getCanonicalType(ArgType.getNonReferenceType()).
568           getTypePtr() ==
569           getContext().getCanonicalType(NewArg->getType()).getTypePtr() &&
570           "type mismatch in call argument!");
571
572    NewArgs.push_back(std::make_pair(EmitCallArg(*NewArg, ArgType),
573                                     ArgType));
574
575  }
576
577  // Either we've emitted all the call args, or we have a call to a
578  // variadic function.
579  assert((NewArg == E->placement_arg_end() || NewFTy->isVariadic()) &&
580         "Extra arguments in non-variadic function!");
581
582  // If we still have any arguments, emit them using the type of the argument.
583  for (CXXNewExpr::const_arg_iterator NewArgEnd = E->placement_arg_end();
584       NewArg != NewArgEnd; ++NewArg) {
585    QualType ArgType = NewArg->getType();
586    NewArgs.push_back(std::make_pair(EmitCallArg(*NewArg, ArgType),
587                                     ArgType));
588  }
589
590  // Emit the call to new.
591  RValue RV =
592    EmitCall(CGM.getTypes().getFunctionInfo(NewFTy->getResultType(), NewArgs),
593             CGM.GetAddrOfFunction(GlobalDecl(NewFD)),
594             NewArgs, NewFD);
595
596  // If an allocation function is declared with an empty exception specification
597  // it returns null to indicate failure to allocate storage. [expr.new]p13.
598  // (We don't need to check for null when there's no new initializer and
599  // we're allocating a POD type).
600  bool NullCheckResult = NewFTy->hasEmptyExceptionSpec() &&
601    !(AllocType->isPODType() && !E->hasInitializer());
602
603  llvm::BasicBlock *NewNull = 0;
604  llvm::BasicBlock *NewNotNull = 0;
605  llvm::BasicBlock *NewEnd = 0;
606
607  llvm::Value *NewPtr = RV.getScalarVal();
608
609  if (NullCheckResult) {
610    NewNull = createBasicBlock("new.null");
611    NewNotNull = createBasicBlock("new.notnull");
612    NewEnd = createBasicBlock("new.end");
613
614    llvm::Value *IsNull =
615      Builder.CreateICmpEQ(NewPtr,
616                           llvm::Constant::getNullValue(NewPtr->getType()),
617                           "isnull");
618
619    Builder.CreateCondBr(IsNull, NewNull, NewNotNull);
620    EmitBlock(NewNotNull);
621  }
622
623  NewPtr = Builder.CreateBitCast(NewPtr, ConvertType(E->getType()));
624
625  if (AllocType->isPODType()) {
626    if (E->getNumConstructorArgs() > 0) {
627      assert(E->getNumConstructorArgs() == 1 &&
628             "Can only have one argument to initializer of POD type.");
629
630      const Expr *Init = E->getConstructorArg(0);
631
632      if (!hasAggregateLLVMType(AllocType))
633        Builder.CreateStore(EmitScalarExpr(Init), NewPtr);
634      else if (AllocType->isAnyComplexType())
635        EmitComplexExprIntoAddr(Init, NewPtr, AllocType.isVolatileQualified());
636      else
637        EmitAggExpr(Init, NewPtr, AllocType.isVolatileQualified());
638    }
639  } else {
640    // Call the constructor.
641    CXXConstructorDecl *Ctor = E->getConstructor();
642
643    EmitCXXConstructorCall(Ctor, Ctor_Complete, NewPtr,
644                           E->constructor_arg_begin(),
645                           E->constructor_arg_end());
646  }
647
648  if (NullCheckResult) {
649    Builder.CreateBr(NewEnd);
650    EmitBlock(NewNull);
651    Builder.CreateBr(NewEnd);
652    EmitBlock(NewEnd);
653
654    llvm::PHINode *PHI = Builder.CreatePHI(NewPtr->getType());
655    PHI->reserveOperandSpace(2);
656    PHI->addIncoming(NewPtr, NewNotNull);
657    PHI->addIncoming(llvm::Constant::getNullValue(NewPtr->getType()), NewNull);
658
659    NewPtr = PHI;
660  }
661
662  return NewPtr;
663}
664
665void CodeGenFunction::EmitCXXDeleteExpr(const CXXDeleteExpr *E) {
666  if (E->isArrayForm()) {
667    ErrorUnsupported(E, "delete[] expression");
668    return;
669  };
670
671  QualType DeleteTy =
672    E->getArgument()->getType()->getAs<PointerType>()->getPointeeType();
673
674  llvm::Value *Ptr = EmitScalarExpr(E->getArgument());
675
676  // Null check the pointer.
677  llvm::BasicBlock *DeleteNotNull = createBasicBlock("delete.notnull");
678  llvm::BasicBlock *DeleteEnd = createBasicBlock("delete.end");
679
680  llvm::Value *IsNull =
681    Builder.CreateICmpEQ(Ptr, llvm::Constant::getNullValue(Ptr->getType()),
682                         "isnull");
683
684  Builder.CreateCondBr(IsNull, DeleteEnd, DeleteNotNull);
685  EmitBlock(DeleteNotNull);
686
687  // Call the destructor if necessary.
688  if (const RecordType *RT = DeleteTy->getAs<RecordType>()) {
689    if (CXXRecordDecl *RD = dyn_cast<CXXRecordDecl>(RT->getDecl())) {
690      if (!RD->hasTrivialDestructor()) {
691        const CXXDestructorDecl *Dtor = RD->getDestructor(getContext());
692        if (Dtor->isVirtual()) {
693          ErrorUnsupported(E, "delete expression with virtual destructor");
694          return;
695        }
696
697        EmitCXXDestructorCall(Dtor, Dtor_Complete, Ptr);
698      }
699    }
700  }
701
702  // Call delete.
703  FunctionDecl *DeleteFD = E->getOperatorDelete();
704  const FunctionProtoType *DeleteFTy =
705    DeleteFD->getType()->getAsFunctionProtoType();
706
707  CallArgList DeleteArgs;
708
709  QualType ArgTy = DeleteFTy->getArgType(0);
710  llvm::Value *DeletePtr = Builder.CreateBitCast(Ptr, ConvertType(ArgTy));
711  DeleteArgs.push_back(std::make_pair(RValue::get(DeletePtr), ArgTy));
712
713  // Emit the call to delete.
714  EmitCall(CGM.getTypes().getFunctionInfo(DeleteFTy->getResultType(),
715                                          DeleteArgs),
716           CGM.GetAddrOfFunction(GlobalDecl(DeleteFD)),
717           DeleteArgs, DeleteFD);
718
719  EmitBlock(DeleteEnd);
720}
721
722void CodeGenModule::EmitCXXConstructors(const CXXConstructorDecl *D) {
723  EmitGlobal(GlobalDecl(D, Ctor_Complete));
724  EmitGlobal(GlobalDecl(D, Ctor_Base));
725}
726
727void CodeGenModule::EmitCXXConstructor(const CXXConstructorDecl *D,
728                                       CXXCtorType Type) {
729
730  llvm::Function *Fn = GetAddrOfCXXConstructor(D, Type);
731
732  CodeGenFunction(*this).GenerateCode(D, Fn);
733
734  SetFunctionDefinitionAttributes(D, Fn);
735  SetLLVMFunctionAttributesForDefinition(D, Fn);
736}
737
738llvm::Function *
739CodeGenModule::GetAddrOfCXXConstructor(const CXXConstructorDecl *D,
740                                       CXXCtorType Type) {
741  const llvm::FunctionType *FTy =
742    getTypes().GetFunctionType(getTypes().getFunctionInfo(D), false);
743
744  const char *Name = getMangledCXXCtorName(D, Type);
745  return cast<llvm::Function>(
746                      GetOrCreateLLVMFunction(Name, FTy, GlobalDecl(D, Type)));
747}
748
749const char *CodeGenModule::getMangledCXXCtorName(const CXXConstructorDecl *D,
750                                                 CXXCtorType Type) {
751  llvm::SmallString<256> Name;
752  llvm::raw_svector_ostream Out(Name);
753  mangleCXXCtor(D, Type, Context, Out);
754
755  Name += '\0';
756  return UniqueMangledName(Name.begin(), Name.end());
757}
758
759void CodeGenModule::EmitCXXDestructors(const CXXDestructorDecl *D) {
760  EmitCXXDestructor(D, Dtor_Complete);
761  EmitCXXDestructor(D, Dtor_Base);
762}
763
764void CodeGenModule::EmitCXXDestructor(const CXXDestructorDecl *D,
765                                      CXXDtorType Type) {
766  llvm::Function *Fn = GetAddrOfCXXDestructor(D, Type);
767
768  CodeGenFunction(*this).GenerateCode(D, Fn);
769
770  SetFunctionDefinitionAttributes(D, Fn);
771  SetLLVMFunctionAttributesForDefinition(D, Fn);
772}
773
774llvm::Function *
775CodeGenModule::GetAddrOfCXXDestructor(const CXXDestructorDecl *D,
776                                      CXXDtorType Type) {
777  const llvm::FunctionType *FTy =
778    getTypes().GetFunctionType(getTypes().getFunctionInfo(D), false);
779
780  const char *Name = getMangledCXXDtorName(D, Type);
781  return cast<llvm::Function>(
782                      GetOrCreateLLVMFunction(Name, FTy, GlobalDecl(D, Type)));
783}
784
785const char *CodeGenModule::getMangledCXXDtorName(const CXXDestructorDecl *D,
786                                                 CXXDtorType Type) {
787  llvm::SmallString<256> Name;
788  llvm::raw_svector_ostream Out(Name);
789  mangleCXXDtor(D, Type, Context, Out);
790
791  Name += '\0';
792  return UniqueMangledName(Name.begin(), Name.end());
793}
794
795llvm::Constant *CodeGenModule::GenerateRtti(const CXXRecordDecl *RD) {
796  llvm::Type *Ptr8Ty;
797  Ptr8Ty = llvm::PointerType::get(llvm::Type::getInt8Ty(VMContext), 0);
798  llvm::Constant *Rtti = llvm::Constant::getNullValue(Ptr8Ty);
799
800  if (!getContext().getLangOptions().Rtti)
801    return Rtti;
802
803  llvm::SmallString<256> OutName;
804  llvm::raw_svector_ostream Out(OutName);
805  QualType ClassTy;
806  ClassTy = getContext().getTagDeclType(RD);
807  mangleCXXRtti(ClassTy, getContext(), Out);
808  llvm::GlobalVariable::LinkageTypes linktype;
809  linktype = llvm::GlobalValue::WeakAnyLinkage;
810  std::vector<llvm::Constant *> info;
811  // assert(0 && "FIXME: implement rtti descriptor");
812  // FIXME: descriptor
813  info.push_back(llvm::Constant::getNullValue(Ptr8Ty));
814  // assert(0 && "FIXME: implement rtti ts");
815  // FIXME: TS
816  info.push_back(llvm::Constant::getNullValue(Ptr8Ty));
817
818  llvm::Constant *C;
819  llvm::ArrayType *type = llvm::ArrayType::get(Ptr8Ty, info.size());
820  C = llvm::ConstantArray::get(type, info);
821  Rtti = new llvm::GlobalVariable(getModule(), type, true, linktype, C,
822                                  Out.str());
823  Rtti = llvm::ConstantExpr::getBitCast(Rtti, Ptr8Ty);
824  return Rtti;
825}
826
827class VtableBuilder {
828public:
829  /// Index_t - Vtable index type.
830  typedef uint64_t Index_t;
831private:
832  std::vector<llvm::Constant *> &methods;
833  std::vector<llvm::Constant *> submethods;
834  llvm::Type *Ptr8Ty;
835  /// Class - The most derived class that this vtable is being built for.
836  const CXXRecordDecl *Class;
837  /// BLayout - Layout for the most derived class that this vtable is being
838  /// built for.
839  const ASTRecordLayout &BLayout;
840  llvm::SmallSet<const CXXRecordDecl *, 32> IndirectPrimary;
841  llvm::SmallSet<const CXXRecordDecl *, 32> SeenVBase;
842  llvm::Constant *rtti;
843  llvm::LLVMContext &VMContext;
844  CodeGenModule &CGM;  // Per-module state.
845  /// Index - Maps a method decl into a vtable index.  Useful for virtual
846  /// dispatch codegen.
847  llvm::DenseMap<const CXXMethodDecl *, Index_t> Index;
848  llvm::DenseMap<const CXXMethodDecl *, Index_t> VCall;
849  llvm::DenseMap<const CXXMethodDecl *, Index_t> VCallOffset;
850  std::vector<Index_t> VCalls;
851  typedef CXXRecordDecl::method_iterator method_iter;
852public:
853  VtableBuilder(std::vector<llvm::Constant *> &meth,
854                const CXXRecordDecl *c,
855                CodeGenModule &cgm)
856    : methods(meth), Class(c), BLayout(cgm.getContext().getASTRecordLayout(c)),
857      rtti(cgm.GenerateRtti(c)), VMContext(cgm.getModule().getContext()),
858      CGM(cgm) {
859    Ptr8Ty = llvm::PointerType::get(llvm::Type::getInt8Ty(VMContext), 0);
860  }
861
862  llvm::DenseMap<const CXXMethodDecl *, Index_t> &getIndex() { return Index; }
863
864  llvm::Constant *wrap(Index_t i) {
865    llvm::Constant *m;
866    m = llvm::ConstantInt::get(llvm::Type::getInt64Ty(VMContext), i);
867    return llvm::ConstantExpr::getIntToPtr(m, Ptr8Ty);
868  }
869
870  llvm::Constant *wrap(llvm::Constant *m) {
871    return llvm::ConstantExpr::getBitCast(m, Ptr8Ty);
872  }
873
874  void GenerateVBaseOffsets(std::vector<llvm::Constant *> &offsets,
875                            const CXXRecordDecl *RD, uint64_t Offset) {
876    for (CXXRecordDecl::base_class_const_iterator i =RD->bases_begin(),
877           e = RD->bases_end(); i != e; ++i) {
878      const CXXRecordDecl *Base =
879        cast<CXXRecordDecl>(i->getType()->getAs<RecordType>()->getDecl());
880      if (i->isVirtual() && !SeenVBase.count(Base)) {
881        SeenVBase.insert(Base);
882        int64_t BaseOffset = -(Offset/8) + BLayout.getVBaseClassOffset(Base)/8;
883        llvm::Constant *m = wrap(BaseOffset);
884        m = wrap((0?700:0) + BaseOffset);
885        offsets.push_back(m);
886      }
887      GenerateVBaseOffsets(offsets, Base, Offset);
888    }
889  }
890
891  void StartNewTable() {
892    SeenVBase.clear();
893  }
894
895  bool OverrideMethod(const CXXMethodDecl *MD, llvm::Constant *m,
896                      bool MorallyVirtual, Index_t Offset) {
897    typedef CXXMethodDecl::method_iterator meth_iter;
898
899    // FIXME: Don't like the nested loops.  For very large inheritance
900    // heirarchies we could have a table on the side with the final overridder
901    // and just replace each instance of an overridden method once.  Would be
902    // nice to measure the cost/benefit on real code.
903
904    // If we can find a previously allocated slot for this, reuse it.
905    for (meth_iter mi = MD->begin_overridden_methods(),
906           e = MD->end_overridden_methods();
907         mi != e; ++mi) {
908      const CXXMethodDecl *OMD = *mi;
909      llvm::Constant *om;
910      om = CGM.GetAddrOfFunction(GlobalDecl(OMD), Ptr8Ty);
911      om = llvm::ConstantExpr::getBitCast(om, Ptr8Ty);
912
913      for (Index_t i = 0, e = submethods.size();
914           i != e; ++i) {
915        // FIXME: begin_overridden_methods might be too lax, covariance */
916        if (submethods[i] == om) {
917          // FIXME: thunks
918          submethods[i] = m;
919          Index[MD] = i;
920          if (MorallyVirtual) {
921            VCallOffset[MD] = Offset/8;
922            VCalls[VCall[OMD]] = Offset/8 - VCallOffset[OMD];
923          }
924          // submethods[VCall[OMD]] = wrap(Offset/8 - VCallOffset[OMD]);
925          return true;
926        }
927      }
928    }
929
930    return false;
931  }
932
933  void OverrideMethods(const CXXRecordDecl *RD, Index_t AddressPoint,
934                       bool MorallyVirtual, Index_t Offset) {
935    for (method_iter mi = RD->method_begin(), me = RD->method_end(); mi != me;
936         ++mi)
937      if (mi->isVirtual()) {
938        const CXXMethodDecl *MD = *mi;
939        llvm::Constant *m = wrap(CGM.GetAddrOfFunction(GlobalDecl(MD), Ptr8Ty));
940        OverrideMethod(MD, m, MorallyVirtual, Offset);
941      }
942  }
943
944  void AddMethod(const CXXMethodDecl *MD, Index_t AddressPoint,
945                 bool MorallyVirtual, Index_t Offset) {
946    llvm::Constant *m = wrap(CGM.GetAddrOfFunction(GlobalDecl(MD), Ptr8Ty));
947    if (OverrideMethod(MD, m, MorallyVirtual, Offset))
948      return;
949
950    // else allocate a new slot.
951    Index[MD] = submethods.size();
952    // VCall[MD] = Offset;
953    if (MorallyVirtual) {
954      VCallOffset[MD] = Offset/8;
955      Index_t &idx = VCall[MD];
956      // Allocate the first one, after that, we reuse the previous one.
957      if (idx == 0) {
958        idx = VCalls.size()+1;
959        VCallOffset[MD] = Offset/8;
960        VCalls.push_back(0);
961      }
962    }
963    submethods.push_back(m);
964  }
965
966  void AddMethods(const CXXRecordDecl *RD, Index_t AddressPoint,
967                  bool MorallyVirtual, Index_t Offset) {
968    for (method_iter mi = RD->method_begin(), me = RD->method_end(); mi != me;
969         ++mi)
970      if (mi->isVirtual())
971        AddMethod(*mi, AddressPoint, MorallyVirtual, Offset);
972  }
973
974  int64_t GenerateVtableForBase(const CXXRecordDecl *RD, bool forPrimary,
975                                bool Bottom, bool MorallyVirtual,
976                                int64_t Offset, bool ForVirtualBase) {
977    llvm::Constant *m = llvm::Constant::getNullValue(Ptr8Ty);
978    int64_t AddressPoint=0;
979
980    if (RD && !RD->isDynamicClass())
981      return 0;
982
983    const ASTRecordLayout &Layout = CGM.getContext().getASTRecordLayout(RD);
984    const CXXRecordDecl *PrimaryBase = Layout.getPrimaryBase();
985    const bool PrimaryBaseWasVirtual = Layout.getPrimaryBaseWasVirtual();
986
987    std::vector<llvm::Constant *> offsets;
988    // FIXME: Audit, is this right?
989    if (Bottom && (PrimaryBase == 0 || forPrimary || !PrimaryBaseWasVirtual
990                   || Bottom))
991      GenerateVBaseOffsets(offsets, RD, Offset);
992
993    bool Top = true;
994
995    // vtables are composed from the chain of primaries.
996    if (PrimaryBase) {
997      if (PrimaryBaseWasVirtual)
998        IndirectPrimary.insert(PrimaryBase);
999      Top = false;
1000      AddressPoint = GenerateVtableForBase(PrimaryBase, true, false,
1001                                           PrimaryBaseWasVirtual|MorallyVirtual,
1002                                           Offset, PrimaryBaseWasVirtual);
1003    }
1004
1005    // And add the virtuals for the class to the primary vtable.
1006    AddMethods(RD, AddressPoint, MorallyVirtual, Offset);
1007
1008    if (!Bottom)
1009      return AddressPoint;
1010
1011    StartNewTable();
1012    // FIXME: Cleanup.
1013    if (!ForVirtualBase) {
1014      // then virtual base offsets...
1015      for (std::vector<llvm::Constant *>::reverse_iterator i = offsets.rbegin(),
1016             e = offsets.rend(); i != e; ++i)
1017        methods.push_back(*i);
1018    }
1019
1020    // The vcalls come first...
1021    for (std::vector<Index_t>::iterator i=VCalls.begin(), e=VCalls.end();
1022         i < e; ++i)
1023      methods.push_back(wrap((0?600:0) + *i));
1024    VCalls.clear();
1025
1026    if (ForVirtualBase) {
1027      // then virtual base offsets...
1028      for (std::vector<llvm::Constant *>::reverse_iterator i = offsets.rbegin(),
1029             e = offsets.rend(); i != e; ++i)
1030        methods.push_back(*i);
1031    }
1032
1033    m = wrap(-(Offset/8));
1034    methods.push_back(m);
1035    methods.push_back(rtti);
1036    AddressPoint = methods.size();
1037
1038    methods.insert(methods.end(), submethods.begin(), submethods.end());
1039    submethods.clear();
1040
1041    // and then the non-virtual bases.
1042    for (CXXRecordDecl::base_class_const_iterator i = RD->bases_begin(),
1043           e = RD->bases_end(); i != e; ++i) {
1044      if (i->isVirtual())
1045        continue;
1046      const CXXRecordDecl *Base =
1047        cast<CXXRecordDecl>(i->getType()->getAs<RecordType>()->getDecl());
1048      if (Base != PrimaryBase || PrimaryBaseWasVirtual) {
1049        uint64_t o = Offset + Layout.getBaseClassOffset(Base);
1050        StartNewTable();
1051        GenerateVtableForBase(Base, true, true, false, o, false);
1052      }
1053    }
1054    return AddressPoint;
1055  }
1056
1057  void GenerateVtableForVBases(const CXXRecordDecl *RD,
1058                               const CXXRecordDecl *Class) {
1059    for (CXXRecordDecl::base_class_const_iterator i = RD->bases_begin(),
1060           e = RD->bases_end(); i != e; ++i) {
1061      const CXXRecordDecl *Base =
1062        cast<CXXRecordDecl>(i->getType()->getAs<RecordType>()->getDecl());
1063      if (i->isVirtual() && !IndirectPrimary.count(Base)) {
1064        // Mark it so we don't output it twice.
1065        IndirectPrimary.insert(Base);
1066        StartNewTable();
1067        int64_t BaseOffset = BLayout.getVBaseClassOffset(Base);
1068        GenerateVtableForBase(Base, false, true, true, BaseOffset, true);
1069      }
1070      if (Base->getNumVBases())
1071        GenerateVtableForVBases(Base, Class);
1072    }
1073  }
1074};
1075
1076class VtableInfo {
1077public:
1078  typedef VtableBuilder::Index_t Index_t;
1079private:
1080  CodeGenModule &CGM;  // Per-module state.
1081  /// Index_t - Vtable index type.
1082  typedef llvm::DenseMap<const CXXMethodDecl *, Index_t> ElTy;
1083  typedef llvm::DenseMap<const CXXRecordDecl *, ElTy *> MapTy;
1084  // FIXME: Move to Context.
1085  static MapTy IndexFor;
1086public:
1087  VtableInfo(CodeGenModule &cgm) : CGM(cgm) { }
1088  void register_index(const CXXRecordDecl *RD, const ElTy &e) {
1089    assert(IndexFor.find(RD) == IndexFor.end() && "Don't compute vtbl twice");
1090    // We own a copy of this, it will go away shortly.
1091    new ElTy (e);
1092    IndexFor[RD] = new ElTy (e);
1093  }
1094  Index_t lookup(const CXXMethodDecl *MD) {
1095    const CXXRecordDecl *RD = MD->getParent();
1096    MapTy::iterator I = IndexFor.find(RD);
1097    if (I == IndexFor.end()) {
1098      std::vector<llvm::Constant *> methods;
1099      VtableBuilder b(methods, RD, CGM);
1100      b.GenerateVtableForBase(RD, true, true, false, 0, false);
1101      b.GenerateVtableForVBases(RD, RD);
1102      register_index(RD, b.getIndex());
1103      I = IndexFor.find(RD);
1104    }
1105    assert(I->second->find(MD)!=I->second->end() && "Can't find vtable index");
1106    return (*I->second)[MD];
1107  }
1108};
1109
1110// FIXME: Move to Context.
1111VtableInfo::MapTy VtableInfo::IndexFor;
1112
1113llvm::Value *CodeGenFunction::GenerateVtable(const CXXRecordDecl *RD) {
1114  llvm::SmallString<256> OutName;
1115  llvm::raw_svector_ostream Out(OutName);
1116  QualType ClassTy;
1117  ClassTy = getContext().getTagDeclType(RD);
1118  mangleCXXVtable(ClassTy, getContext(), Out);
1119  llvm::GlobalVariable::LinkageTypes linktype;
1120  linktype = llvm::GlobalValue::WeakAnyLinkage;
1121  std::vector<llvm::Constant *> methods;
1122  llvm::Type *Ptr8Ty=llvm::PointerType::get(llvm::Type::getInt8Ty(VMContext),0);
1123  int64_t Offset;
1124
1125  VtableBuilder b(methods, RD, CGM);
1126
1127  // First comes the vtables for all the non-virtual bases...
1128  Offset = b.GenerateVtableForBase(RD, true, true, false, 0, false);
1129
1130  // then the vtables for all the virtual bases.
1131  b.GenerateVtableForVBases(RD, RD);
1132
1133  llvm::Constant *C;
1134  llvm::ArrayType *type = llvm::ArrayType::get(Ptr8Ty, methods.size());
1135  C = llvm::ConstantArray::get(type, methods);
1136  llvm::Value *vtable = new llvm::GlobalVariable(CGM.getModule(), type, true,
1137                                                 linktype, C, Out.str());
1138  vtable = Builder.CreateBitCast(vtable, Ptr8Ty);
1139  vtable = Builder.CreateGEP(vtable,
1140                       llvm::ConstantInt::get(llvm::Type::getInt64Ty(VMContext),
1141                                              Offset*LLVMPointerWidth/8));
1142  return vtable;
1143}
1144
1145// FIXME: move to Context
1146static VtableInfo *vtableinfo;
1147
1148llvm::Value *
1149CodeGenFunction::BuildVirtualCall(const CXXMethodDecl *MD, llvm::Value *&This,
1150                                  const llvm::Type *Ty) {
1151  // FIXME: If we know the dynamic type, we don't have to do a virtual dispatch.
1152
1153  // FIXME: move to Context
1154  if (vtableinfo == 0)
1155    vtableinfo = new VtableInfo(CGM);
1156
1157  VtableInfo::Index_t Idx = vtableinfo->lookup(MD);
1158
1159  Ty = llvm::PointerType::get(Ty, 0);
1160  Ty = llvm::PointerType::get(Ty, 0);
1161  Ty = llvm::PointerType::get(Ty, 0);
1162  llvm::Value *vtbl = Builder.CreateBitCast(This, Ty);
1163  vtbl = Builder.CreateLoad(vtbl);
1164  llvm::Value *vfn = Builder.CreateConstInBoundsGEP1_64(vtbl,
1165                                                        Idx, "vfn");
1166  vfn = Builder.CreateLoad(vfn);
1167  return vfn;
1168}
1169
1170/// EmitClassAggrMemberwiseCopy - This routine generates code to copy a class
1171/// array of objects from SrcValue to DestValue. Copying can be either a bitwise
1172/// copy or via a copy constructor call.
1173//  FIXME. Consolidate this with EmitCXXAggrConstructorCall.
1174void CodeGenFunction::EmitClassAggrMemberwiseCopy(llvm::Value *Dest,
1175                                            llvm::Value *Src,
1176                                            const ArrayType *Array,
1177                                            const CXXRecordDecl *BaseClassDecl,
1178                                            QualType Ty) {
1179  const ConstantArrayType *CA = dyn_cast<ConstantArrayType>(Array);
1180  assert(CA && "VLA cannot be copied over");
1181  bool BitwiseCopy = BaseClassDecl->hasTrivialCopyConstructor();
1182
1183  // Create a temporary for the loop index and initialize it with 0.
1184  llvm::Value *IndexPtr = CreateTempAlloca(llvm::Type::getInt64Ty(VMContext),
1185                                           "loop.index");
1186  llvm::Value* zeroConstant =
1187    llvm::Constant::getNullValue(llvm::Type::getInt64Ty(VMContext));
1188    Builder.CreateStore(zeroConstant, IndexPtr, false);
1189  // Start the loop with a block that tests the condition.
1190  llvm::BasicBlock *CondBlock = createBasicBlock("for.cond");
1191  llvm::BasicBlock *AfterFor = createBasicBlock("for.end");
1192
1193  EmitBlock(CondBlock);
1194
1195  llvm::BasicBlock *ForBody = createBasicBlock("for.body");
1196  // Generate: if (loop-index < number-of-elements fall to the loop body,
1197  // otherwise, go to the block after the for-loop.
1198  uint64_t NumElements = getContext().getConstantArrayElementCount(CA);
1199  llvm::Value * NumElementsPtr =
1200    llvm::ConstantInt::get(llvm::Type::getInt64Ty(VMContext), NumElements);
1201  llvm::Value *Counter = Builder.CreateLoad(IndexPtr);
1202  llvm::Value *IsLess = Builder.CreateICmpULT(Counter, NumElementsPtr,
1203                                              "isless");
1204  // If the condition is true, execute the body.
1205  Builder.CreateCondBr(IsLess, ForBody, AfterFor);
1206
1207  EmitBlock(ForBody);
1208  llvm::BasicBlock *ContinueBlock = createBasicBlock("for.inc");
1209  // Inside the loop body, emit the constructor call on the array element.
1210  Counter = Builder.CreateLoad(IndexPtr);
1211  Src = Builder.CreateInBoundsGEP(Src, Counter, "srcaddress");
1212  Dest = Builder.CreateInBoundsGEP(Dest, Counter, "destaddress");
1213  if (BitwiseCopy)
1214    EmitAggregateCopy(Dest, Src, Ty);
1215  else if (CXXConstructorDecl *BaseCopyCtor =
1216           BaseClassDecl->getCopyConstructor(getContext(), 0)) {
1217    llvm::Value *Callee = CGM.GetAddrOfCXXConstructor(BaseCopyCtor,
1218                                                      Ctor_Complete);
1219    CallArgList CallArgs;
1220    // Push the this (Dest) ptr.
1221    CallArgs.push_back(std::make_pair(RValue::get(Dest),
1222                                      BaseCopyCtor->getThisType(getContext())));
1223
1224    // Push the Src ptr.
1225    CallArgs.push_back(std::make_pair(RValue::get(Src),
1226                                      BaseCopyCtor->getParamDecl(0)->getType()));
1227    QualType ResultType =
1228      BaseCopyCtor->getType()->getAsFunctionType()->getResultType();
1229    EmitCall(CGM.getTypes().getFunctionInfo(ResultType, CallArgs),
1230             Callee, CallArgs, BaseCopyCtor);
1231  }
1232  EmitBlock(ContinueBlock);
1233
1234  // Emit the increment of the loop counter.
1235  llvm::Value *NextVal = llvm::ConstantInt::get(Counter->getType(), 1);
1236  Counter = Builder.CreateLoad(IndexPtr);
1237  NextVal = Builder.CreateAdd(Counter, NextVal, "inc");
1238  Builder.CreateStore(NextVal, IndexPtr, false);
1239
1240  // Finally, branch back up to the condition for the next iteration.
1241  EmitBranch(CondBlock);
1242
1243  // Emit the fall-through block.
1244  EmitBlock(AfterFor, true);
1245}
1246
1247/// EmitClassAggrCopyAssignment - This routine generates code to assign a class
1248/// array of objects from SrcValue to DestValue. Assignment can be either a
1249/// bitwise assignment or via a copy assignment operator function call.
1250/// FIXME. This can be consolidated with EmitClassAggrMemberwiseCopy
1251void CodeGenFunction::EmitClassAggrCopyAssignment(llvm::Value *Dest,
1252                                            llvm::Value *Src,
1253                                            const ArrayType *Array,
1254                                            const CXXRecordDecl *BaseClassDecl,
1255                                            QualType Ty) {
1256  const ConstantArrayType *CA = dyn_cast<ConstantArrayType>(Array);
1257  assert(CA && "VLA cannot be asssigned");
1258  bool BitwiseAssign = BaseClassDecl->hasTrivialCopyAssignment();
1259
1260  // Create a temporary for the loop index and initialize it with 0.
1261  llvm::Value *IndexPtr = CreateTempAlloca(llvm::Type::getInt64Ty(VMContext),
1262                                           "loop.index");
1263  llvm::Value* zeroConstant =
1264  llvm::Constant::getNullValue(llvm::Type::getInt64Ty(VMContext));
1265  Builder.CreateStore(zeroConstant, IndexPtr, false);
1266  // Start the loop with a block that tests the condition.
1267  llvm::BasicBlock *CondBlock = createBasicBlock("for.cond");
1268  llvm::BasicBlock *AfterFor = createBasicBlock("for.end");
1269
1270  EmitBlock(CondBlock);
1271
1272  llvm::BasicBlock *ForBody = createBasicBlock("for.body");
1273  // Generate: if (loop-index < number-of-elements fall to the loop body,
1274  // otherwise, go to the block after the for-loop.
1275  uint64_t NumElements = getContext().getConstantArrayElementCount(CA);
1276  llvm::Value * NumElementsPtr =
1277  llvm::ConstantInt::get(llvm::Type::getInt64Ty(VMContext), NumElements);
1278  llvm::Value *Counter = Builder.CreateLoad(IndexPtr);
1279  llvm::Value *IsLess = Builder.CreateICmpULT(Counter, NumElementsPtr,
1280                                              "isless");
1281  // If the condition is true, execute the body.
1282  Builder.CreateCondBr(IsLess, ForBody, AfterFor);
1283
1284  EmitBlock(ForBody);
1285  llvm::BasicBlock *ContinueBlock = createBasicBlock("for.inc");
1286  // Inside the loop body, emit the assignment operator call on array element.
1287  Counter = Builder.CreateLoad(IndexPtr);
1288  Src = Builder.CreateInBoundsGEP(Src, Counter, "srcaddress");
1289  Dest = Builder.CreateInBoundsGEP(Dest, Counter, "destaddress");
1290  const CXXMethodDecl *MD = 0;
1291  if (BitwiseAssign)
1292    EmitAggregateCopy(Dest, Src, Ty);
1293  else {
1294    bool hasCopyAssign = BaseClassDecl->hasConstCopyAssignment(getContext(),
1295                                                               MD);
1296    assert(hasCopyAssign && "EmitClassAggrCopyAssignment - No user assign");
1297    (void)hasCopyAssign;
1298    const FunctionProtoType *FPT = MD->getType()->getAsFunctionProtoType();
1299    const llvm::Type *LTy =
1300    CGM.getTypes().GetFunctionType(CGM.getTypes().getFunctionInfo(MD),
1301                                   FPT->isVariadic());
1302    llvm::Constant *Callee = CGM.GetAddrOfFunction(GlobalDecl(MD), LTy);
1303
1304    CallArgList CallArgs;
1305    // Push the this (Dest) ptr.
1306    CallArgs.push_back(std::make_pair(RValue::get(Dest),
1307                                      MD->getThisType(getContext())));
1308
1309    // Push the Src ptr.
1310    CallArgs.push_back(std::make_pair(RValue::get(Src),
1311                                      MD->getParamDecl(0)->getType()));
1312    QualType ResultType =
1313    MD->getType()->getAsFunctionType()->getResultType();
1314    EmitCall(CGM.getTypes().getFunctionInfo(ResultType, CallArgs),
1315             Callee, CallArgs, MD);
1316  }
1317  EmitBlock(ContinueBlock);
1318
1319  // Emit the increment of the loop counter.
1320  llvm::Value *NextVal = llvm::ConstantInt::get(Counter->getType(), 1);
1321  Counter = Builder.CreateLoad(IndexPtr);
1322  NextVal = Builder.CreateAdd(Counter, NextVal, "inc");
1323  Builder.CreateStore(NextVal, IndexPtr, false);
1324
1325  // Finally, branch back up to the condition for the next iteration.
1326  EmitBranch(CondBlock);
1327
1328  // Emit the fall-through block.
1329  EmitBlock(AfterFor, true);
1330}
1331
1332/// EmitClassMemberwiseCopy - This routine generates code to copy a class
1333/// object from SrcValue to DestValue. Copying can be either a bitwise copy
1334/// or via a copy constructor call.
1335void CodeGenFunction::EmitClassMemberwiseCopy(
1336                        llvm::Value *Dest, llvm::Value *Src,
1337                        const CXXRecordDecl *ClassDecl,
1338                        const CXXRecordDecl *BaseClassDecl, QualType Ty) {
1339  if (ClassDecl) {
1340    Dest = AddressCXXOfBaseClass(Dest, ClassDecl, BaseClassDecl);
1341    Src = AddressCXXOfBaseClass(Src, ClassDecl, BaseClassDecl) ;
1342  }
1343  if (BaseClassDecl->hasTrivialCopyConstructor()) {
1344    EmitAggregateCopy(Dest, Src, Ty);
1345    return;
1346  }
1347
1348  if (CXXConstructorDecl *BaseCopyCtor =
1349      BaseClassDecl->getCopyConstructor(getContext(), 0)) {
1350    llvm::Value *Callee = CGM.GetAddrOfCXXConstructor(BaseCopyCtor,
1351                                                      Ctor_Complete);
1352    CallArgList CallArgs;
1353    // Push the this (Dest) ptr.
1354    CallArgs.push_back(std::make_pair(RValue::get(Dest),
1355                                      BaseCopyCtor->getThisType(getContext())));
1356
1357    // Push the Src ptr.
1358    CallArgs.push_back(std::make_pair(RValue::get(Src),
1359                       BaseCopyCtor->getParamDecl(0)->getType()));
1360    QualType ResultType =
1361    BaseCopyCtor->getType()->getAsFunctionType()->getResultType();
1362    EmitCall(CGM.getTypes().getFunctionInfo(ResultType, CallArgs),
1363             Callee, CallArgs, BaseCopyCtor);
1364  }
1365}
1366
1367/// EmitClassCopyAssignment - This routine generates code to copy assign a class
1368/// object from SrcValue to DestValue. Assignment can be either a bitwise
1369/// assignment of via an assignment operator call.
1370// FIXME. Consolidate this with EmitClassMemberwiseCopy as they share a lot.
1371void CodeGenFunction::EmitClassCopyAssignment(
1372                                        llvm::Value *Dest, llvm::Value *Src,
1373                                        const CXXRecordDecl *ClassDecl,
1374                                        const CXXRecordDecl *BaseClassDecl,
1375                                        QualType Ty) {
1376  if (ClassDecl) {
1377    Dest = AddressCXXOfBaseClass(Dest, ClassDecl, BaseClassDecl);
1378    Src = AddressCXXOfBaseClass(Src, ClassDecl, BaseClassDecl) ;
1379  }
1380  if (BaseClassDecl->hasTrivialCopyAssignment()) {
1381    EmitAggregateCopy(Dest, Src, Ty);
1382    return;
1383  }
1384
1385  const CXXMethodDecl *MD = 0;
1386  bool ConstCopyAssignOp = BaseClassDecl->hasConstCopyAssignment(getContext(),
1387                                                                 MD);
1388  assert(ConstCopyAssignOp && "EmitClassCopyAssignment - missing copy assign");
1389  (void)ConstCopyAssignOp;
1390
1391  const FunctionProtoType *FPT = MD->getType()->getAsFunctionProtoType();
1392  const llvm::Type *LTy =
1393    CGM.getTypes().GetFunctionType(CGM.getTypes().getFunctionInfo(MD),
1394                                   FPT->isVariadic());
1395  llvm::Constant *Callee = CGM.GetAddrOfFunction(GlobalDecl(MD), LTy);
1396
1397  CallArgList CallArgs;
1398  // Push the this (Dest) ptr.
1399  CallArgs.push_back(std::make_pair(RValue::get(Dest),
1400                                    MD->getThisType(getContext())));
1401
1402  // Push the Src ptr.
1403  CallArgs.push_back(std::make_pair(RValue::get(Src),
1404                                    MD->getParamDecl(0)->getType()));
1405  QualType ResultType =
1406    MD->getType()->getAsFunctionType()->getResultType();
1407  EmitCall(CGM.getTypes().getFunctionInfo(ResultType, CallArgs),
1408           Callee, CallArgs, MD);
1409}
1410
1411/// SynthesizeDefaultConstructor - synthesize a default constructor
1412void
1413CodeGenFunction::SynthesizeDefaultConstructor(const CXXConstructorDecl *CD,
1414                                              const FunctionDecl *FD,
1415                                              llvm::Function *Fn,
1416                                              const FunctionArgList &Args) {
1417  StartFunction(FD, FD->getResultType(), Fn, Args, SourceLocation());
1418  EmitCtorPrologue(CD);
1419  FinishFunction();
1420}
1421
1422/// SynthesizeCXXCopyConstructor - This routine implicitly defines body of a copy
1423/// constructor, in accordance with section 12.8 (p7 and p8) of C++03
1424/// The implicitly-defined copy constructor for class X performs a memberwise
1425/// copy of its subobjects. The order of copying is the same as the order
1426/// of initialization of bases and members in a user-defined constructor
1427/// Each subobject is copied in the manner appropriate to its type:
1428///  if the subobject is of class type, the copy constructor for the class is
1429///  used;
1430///  if the subobject is an array, each element is copied, in the manner
1431///  appropriate to the element type;
1432///  if the subobject is of scalar type, the built-in assignment operator is
1433///  used.
1434/// Virtual base class subobjects shall be copied only once by the
1435/// implicitly-defined copy constructor
1436
1437void CodeGenFunction::SynthesizeCXXCopyConstructor(const CXXConstructorDecl *CD,
1438                                       const FunctionDecl *FD,
1439                                       llvm::Function *Fn,
1440                                       const FunctionArgList &Args) {
1441  const CXXRecordDecl *ClassDecl = cast<CXXRecordDecl>(CD->getDeclContext());
1442  assert(!ClassDecl->hasUserDeclaredCopyConstructor() &&
1443         "SynthesizeCXXCopyConstructor - copy constructor has definition already");
1444  StartFunction(FD, FD->getResultType(), Fn, Args, SourceLocation());
1445
1446  FunctionArgList::const_iterator i = Args.begin();
1447  const VarDecl *ThisArg = i->first;
1448  llvm::Value *ThisObj = GetAddrOfLocalVar(ThisArg);
1449  llvm::Value *LoadOfThis = Builder.CreateLoad(ThisObj, "this");
1450  const VarDecl *SrcArg = (i+1)->first;
1451  llvm::Value *SrcObj = GetAddrOfLocalVar(SrcArg);
1452  llvm::Value *LoadOfSrc = Builder.CreateLoad(SrcObj);
1453
1454  for (CXXRecordDecl::base_class_const_iterator Base = ClassDecl->bases_begin();
1455       Base != ClassDecl->bases_end(); ++Base) {
1456    // FIXME. copy constrution of virtual base NYI
1457    if (Base->isVirtual())
1458      continue;
1459
1460    CXXRecordDecl *BaseClassDecl
1461      = cast<CXXRecordDecl>(Base->getType()->getAs<RecordType>()->getDecl());
1462    EmitClassMemberwiseCopy(LoadOfThis, LoadOfSrc, ClassDecl, BaseClassDecl,
1463                            Base->getType());
1464  }
1465
1466  for (CXXRecordDecl::field_iterator Field = ClassDecl->field_begin(),
1467       FieldEnd = ClassDecl->field_end();
1468       Field != FieldEnd; ++Field) {
1469    QualType FieldType = getContext().getCanonicalType((*Field)->getType());
1470    const ConstantArrayType *Array =
1471      getContext().getAsConstantArrayType(FieldType);
1472    if (Array)
1473      FieldType = getContext().getBaseElementType(FieldType);
1474
1475    if (const RecordType *FieldClassType = FieldType->getAs<RecordType>()) {
1476      CXXRecordDecl *FieldClassDecl
1477        = cast<CXXRecordDecl>(FieldClassType->getDecl());
1478      LValue LHS = EmitLValueForField(LoadOfThis, *Field, false, 0);
1479      LValue RHS = EmitLValueForField(LoadOfSrc, *Field, false, 0);
1480      if (Array) {
1481        const llvm::Type *BasePtr = ConvertType(FieldType);
1482        BasePtr = llvm::PointerType::getUnqual(BasePtr);
1483        llvm::Value *DestBaseAddrPtr =
1484          Builder.CreateBitCast(LHS.getAddress(), BasePtr);
1485        llvm::Value *SrcBaseAddrPtr =
1486          Builder.CreateBitCast(RHS.getAddress(), BasePtr);
1487        EmitClassAggrMemberwiseCopy(DestBaseAddrPtr, SrcBaseAddrPtr, Array,
1488                                    FieldClassDecl, FieldType);
1489      }
1490      else
1491        EmitClassMemberwiseCopy(LHS.getAddress(), RHS.getAddress(),
1492                                0 /*ClassDecl*/, FieldClassDecl, FieldType);
1493      continue;
1494    }
1495    // Do a built-in assignment of scalar data members.
1496    LValue LHS = EmitLValueForField(LoadOfThis, *Field, false, 0);
1497    LValue RHS = EmitLValueForField(LoadOfSrc, *Field, false, 0);
1498    RValue RVRHS = EmitLoadOfLValue(RHS, FieldType);
1499    EmitStoreThroughLValue(RVRHS, LHS, FieldType);
1500  }
1501  FinishFunction();
1502}
1503
1504/// SynthesizeCXXCopyAssignment - Implicitly define copy assignment operator.
1505/// Before the implicitly-declared copy assignment operator for a class is
1506/// implicitly defined, all implicitly- declared copy assignment operators for
1507/// its direct base classes and its nonstatic data members shall have been
1508/// implicitly defined. [12.8-p12]
1509/// The implicitly-defined copy assignment operator for class X performs
1510/// memberwise assignment of its subob- jects. The direct base classes of X are
1511/// assigned first, in the order of their declaration in
1512/// the base-specifier-list, and then the immediate nonstatic data members of X
1513/// are assigned, in the order in which they were declared in the class
1514/// definition.Each subobject is assigned in the manner appropriate to its type:
1515///   if the subobject is of class type, the copy assignment operator for the
1516///   class is used (as if by explicit qualification; that is, ignoring any
1517///   possible virtual overriding functions in more derived classes);
1518///
1519///   if the subobject is an array, each element is assigned, in the manner
1520///   appropriate to the element type;
1521///
1522///   if the subobject is of scalar type, the built-in assignment operator is
1523///   used.
1524void CodeGenFunction::SynthesizeCXXCopyAssignment(const CXXMethodDecl *CD,
1525                                                  const FunctionDecl *FD,
1526                                                  llvm::Function *Fn,
1527                                                  const FunctionArgList &Args) {
1528
1529  const CXXRecordDecl *ClassDecl = cast<CXXRecordDecl>(CD->getDeclContext());
1530  assert(!ClassDecl->hasUserDeclaredCopyAssignment() &&
1531         "SynthesizeCXXCopyAssignment - copy assignment has user declaration");
1532  StartFunction(FD, FD->getResultType(), Fn, Args, SourceLocation());
1533
1534  FunctionArgList::const_iterator i = Args.begin();
1535  const VarDecl *ThisArg = i->first;
1536  llvm::Value *ThisObj = GetAddrOfLocalVar(ThisArg);
1537  llvm::Value *LoadOfThis = Builder.CreateLoad(ThisObj, "this");
1538  const VarDecl *SrcArg = (i+1)->first;
1539  llvm::Value *SrcObj = GetAddrOfLocalVar(SrcArg);
1540  llvm::Value *LoadOfSrc = Builder.CreateLoad(SrcObj);
1541
1542  for (CXXRecordDecl::base_class_const_iterator Base = ClassDecl->bases_begin();
1543       Base != ClassDecl->bases_end(); ++Base) {
1544    // FIXME. copy assignment of virtual base NYI
1545    if (Base->isVirtual())
1546      continue;
1547
1548    CXXRecordDecl *BaseClassDecl
1549      = cast<CXXRecordDecl>(Base->getType()->getAs<RecordType>()->getDecl());
1550    EmitClassCopyAssignment(LoadOfThis, LoadOfSrc, ClassDecl, BaseClassDecl,
1551                            Base->getType());
1552  }
1553
1554  for (CXXRecordDecl::field_iterator Field = ClassDecl->field_begin(),
1555       FieldEnd = ClassDecl->field_end();
1556       Field != FieldEnd; ++Field) {
1557    QualType FieldType = getContext().getCanonicalType((*Field)->getType());
1558    const ConstantArrayType *Array =
1559      getContext().getAsConstantArrayType(FieldType);
1560    if (Array)
1561      FieldType = getContext().getBaseElementType(FieldType);
1562
1563    if (const RecordType *FieldClassType = FieldType->getAs<RecordType>()) {
1564      CXXRecordDecl *FieldClassDecl
1565      = cast<CXXRecordDecl>(FieldClassType->getDecl());
1566      LValue LHS = EmitLValueForField(LoadOfThis, *Field, false, 0);
1567      LValue RHS = EmitLValueForField(LoadOfSrc, *Field, false, 0);
1568      if (Array) {
1569        const llvm::Type *BasePtr = ConvertType(FieldType);
1570        BasePtr = llvm::PointerType::getUnqual(BasePtr);
1571        llvm::Value *DestBaseAddrPtr =
1572          Builder.CreateBitCast(LHS.getAddress(), BasePtr);
1573        llvm::Value *SrcBaseAddrPtr =
1574          Builder.CreateBitCast(RHS.getAddress(), BasePtr);
1575        EmitClassAggrCopyAssignment(DestBaseAddrPtr, SrcBaseAddrPtr, Array,
1576                                    FieldClassDecl, FieldType);
1577      }
1578      else
1579        EmitClassCopyAssignment(LHS.getAddress(), RHS.getAddress(),
1580                               0 /*ClassDecl*/, FieldClassDecl, FieldType);
1581      continue;
1582    }
1583    // Do a built-in assignment of scalar data members.
1584    LValue LHS = EmitLValueForField(LoadOfThis, *Field, false, 0);
1585    LValue RHS = EmitLValueForField(LoadOfSrc, *Field, false, 0);
1586    RValue RVRHS = EmitLoadOfLValue(RHS, FieldType);
1587    EmitStoreThroughLValue(RVRHS, LHS, FieldType);
1588  }
1589
1590  // return *this;
1591  Builder.CreateStore(LoadOfThis, ReturnValue);
1592
1593  FinishFunction();
1594}
1595
1596/// EmitCtorPrologue - This routine generates necessary code to initialize
1597/// base classes and non-static data members belonging to this constructor.
1598/// FIXME: This needs to take a CXXCtorType.
1599void CodeGenFunction::EmitCtorPrologue(const CXXConstructorDecl *CD) {
1600  const CXXRecordDecl *ClassDecl = cast<CXXRecordDecl>(CD->getDeclContext());
1601  // FIXME: Add vbase initialization
1602  llvm::Value *LoadOfThis = 0;
1603
1604  for (CXXConstructorDecl::init_const_iterator B = CD->init_begin(),
1605       E = CD->init_end();
1606       B != E; ++B) {
1607    CXXBaseOrMemberInitializer *Member = (*B);
1608    if (Member->isBaseInitializer()) {
1609      LoadOfThis = LoadCXXThis();
1610      Type *BaseType = Member->getBaseClass();
1611      CXXRecordDecl *BaseClassDecl =
1612        cast<CXXRecordDecl>(BaseType->getAs<RecordType>()->getDecl());
1613      llvm::Value *V = AddressCXXOfBaseClass(LoadOfThis, ClassDecl,
1614                                             BaseClassDecl);
1615      EmitCXXConstructorCall(Member->getConstructor(),
1616                             Ctor_Complete, V,
1617                             Member->const_arg_begin(),
1618                             Member->const_arg_end());
1619    } else {
1620      // non-static data member initilaizers.
1621      FieldDecl *Field = Member->getMember();
1622      QualType FieldType = getContext().getCanonicalType((Field)->getType());
1623      const ConstantArrayType *Array =
1624        getContext().getAsConstantArrayType(FieldType);
1625      if (Array)
1626        FieldType = getContext().getBaseElementType(FieldType);
1627
1628      LoadOfThis = LoadCXXThis();
1629      LValue LHS;
1630      if (FieldType->isReferenceType()) {
1631        // FIXME: This is really ugly; should be refactored somehow
1632        unsigned idx = CGM.getTypes().getLLVMFieldNo(Field);
1633        llvm::Value *V = Builder.CreateStructGEP(LoadOfThis, idx, "tmp");
1634        LHS = LValue::MakeAddr(V, FieldType.getCVRQualifiers(),
1635                               QualType::GCNone, FieldType.getAddressSpace());
1636      } else {
1637        LHS = EmitLValueForField(LoadOfThis, Field, false, 0);
1638      }
1639      if (FieldType->getAs<RecordType>()) {
1640        if (!Field->isAnonymousStructOrUnion()) {
1641          assert(Member->getConstructor() &&
1642                 "EmitCtorPrologue - no constructor to initialize member");
1643          if (Array) {
1644            const llvm::Type *BasePtr = ConvertType(FieldType);
1645            BasePtr = llvm::PointerType::getUnqual(BasePtr);
1646            llvm::Value *BaseAddrPtr =
1647            Builder.CreateBitCast(LHS.getAddress(), BasePtr);
1648            EmitCXXAggrConstructorCall(Member->getConstructor(),
1649                                       Array, BaseAddrPtr);
1650          }
1651          else
1652            EmitCXXConstructorCall(Member->getConstructor(),
1653                                   Ctor_Complete, LHS.getAddress(),
1654                                   Member->const_arg_begin(),
1655                                   Member->const_arg_end());
1656          continue;
1657        }
1658        else {
1659          // Initializing an anonymous union data member.
1660          FieldDecl *anonMember = Member->getAnonUnionMember();
1661          LHS = EmitLValueForField(LHS.getAddress(), anonMember, false, 0);
1662          FieldType = anonMember->getType();
1663        }
1664      }
1665
1666      assert(Member->getNumArgs() == 1 && "Initializer count must be 1 only");
1667      Expr *RhsExpr = *Member->arg_begin();
1668      RValue RHS;
1669      if (FieldType->isReferenceType())
1670        RHS = EmitReferenceBindingToExpr(RhsExpr, FieldType,
1671                                        /*IsInitializer=*/true);
1672      else
1673        RHS = RValue::get(EmitScalarExpr(RhsExpr, true));
1674      EmitStoreThroughLValue(RHS, LHS, FieldType);
1675    }
1676  }
1677
1678  if (!CD->getNumBaseOrMemberInitializers() && !CD->isTrivial()) {
1679    // Nontrivial default constructor with no initializer list. It may still
1680    // have bases classes and/or contain non-static data members which require
1681    // construction.
1682    for (CXXRecordDecl::base_class_const_iterator Base =
1683          ClassDecl->bases_begin();
1684          Base != ClassDecl->bases_end(); ++Base) {
1685      // FIXME. copy assignment of virtual base NYI
1686      if (Base->isVirtual())
1687        continue;
1688
1689      CXXRecordDecl *BaseClassDecl
1690        = cast<CXXRecordDecl>(Base->getType()->getAs<RecordType>()->getDecl());
1691      if (BaseClassDecl->hasTrivialConstructor())
1692        continue;
1693      if (CXXConstructorDecl *BaseCX =
1694            BaseClassDecl->getDefaultConstructor(getContext())) {
1695        LoadOfThis = LoadCXXThis();
1696        llvm::Value *V = AddressCXXOfBaseClass(LoadOfThis, ClassDecl,
1697                                               BaseClassDecl);
1698        EmitCXXConstructorCall(BaseCX, Ctor_Complete, V, 0, 0);
1699      }
1700    }
1701
1702    for (CXXRecordDecl::field_iterator Field = ClassDecl->field_begin(),
1703         FieldEnd = ClassDecl->field_end();
1704         Field != FieldEnd; ++Field) {
1705      QualType FieldType = getContext().getCanonicalType((*Field)->getType());
1706      const ConstantArrayType *Array =
1707        getContext().getAsConstantArrayType(FieldType);
1708      if (Array)
1709        FieldType = getContext().getBaseElementType(FieldType);
1710      if (!FieldType->getAs<RecordType>() || Field->isAnonymousStructOrUnion())
1711        continue;
1712      const RecordType *ClassRec = FieldType->getAs<RecordType>();
1713      CXXRecordDecl *MemberClassDecl =
1714        dyn_cast<CXXRecordDecl>(ClassRec->getDecl());
1715      if (!MemberClassDecl || MemberClassDecl->hasTrivialConstructor())
1716        continue;
1717      if (CXXConstructorDecl *MamberCX =
1718            MemberClassDecl->getDefaultConstructor(getContext())) {
1719        LoadOfThis = LoadCXXThis();
1720        LValue LHS = EmitLValueForField(LoadOfThis, *Field, false, 0);
1721        if (Array) {
1722          const llvm::Type *BasePtr = ConvertType(FieldType);
1723          BasePtr = llvm::PointerType::getUnqual(BasePtr);
1724          llvm::Value *BaseAddrPtr =
1725            Builder.CreateBitCast(LHS.getAddress(), BasePtr);
1726          EmitCXXAggrConstructorCall(MamberCX, Array, BaseAddrPtr);
1727        }
1728        else
1729          EmitCXXConstructorCall(MamberCX, Ctor_Complete, LHS.getAddress(),
1730                                 0, 0);
1731      }
1732    }
1733  }
1734
1735  // Initialize the vtable pointer
1736  if (ClassDecl->isDynamicClass()) {
1737    if (!LoadOfThis)
1738      LoadOfThis = LoadCXXThis();
1739    llvm::Value *VtableField;
1740    llvm::Type *Ptr8Ty, *PtrPtr8Ty;
1741    Ptr8Ty = llvm::PointerType::get(llvm::Type::getInt8Ty(VMContext), 0);
1742    PtrPtr8Ty = llvm::PointerType::get(Ptr8Ty, 0);
1743    VtableField = Builder.CreateBitCast(LoadOfThis, PtrPtr8Ty);
1744    llvm::Value *vtable = GenerateVtable(ClassDecl);
1745    Builder.CreateStore(vtable, VtableField);
1746  }
1747}
1748
1749/// EmitDtorEpilogue - Emit all code that comes at the end of class's
1750/// destructor. This is to call destructors on members and base classes
1751/// in reverse order of their construction.
1752/// FIXME: This needs to take a CXXDtorType.
1753void CodeGenFunction::EmitDtorEpilogue(const CXXDestructorDecl *DD) {
1754  const CXXRecordDecl *ClassDecl = cast<CXXRecordDecl>(DD->getDeclContext());
1755  assert(!ClassDecl->getNumVBases() &&
1756         "FIXME: Destruction of virtual bases not supported");
1757  (void)ClassDecl;  // prevent warning.
1758
1759  for (CXXDestructorDecl::destr_const_iterator *B = DD->destr_begin(),
1760       *E = DD->destr_end(); B != E; ++B) {
1761    uintptr_t BaseOrMember = (*B);
1762    if (DD->isMemberToDestroy(BaseOrMember)) {
1763      FieldDecl *FD = DD->getMemberToDestroy(BaseOrMember);
1764      QualType FieldType = getContext().getCanonicalType((FD)->getType());
1765      const ConstantArrayType *Array =
1766        getContext().getAsConstantArrayType(FieldType);
1767      if (Array)
1768        FieldType = getContext().getBaseElementType(FieldType);
1769      const RecordType *RT = FieldType->getAs<RecordType>();
1770      CXXRecordDecl *FieldClassDecl = cast<CXXRecordDecl>(RT->getDecl());
1771      if (FieldClassDecl->hasTrivialDestructor())
1772        continue;
1773      llvm::Value *LoadOfThis = LoadCXXThis();
1774      LValue LHS = EmitLValueForField(LoadOfThis, FD, false, 0);
1775      if (Array) {
1776        const llvm::Type *BasePtr = ConvertType(FieldType);
1777        BasePtr = llvm::PointerType::getUnqual(BasePtr);
1778        llvm::Value *BaseAddrPtr =
1779          Builder.CreateBitCast(LHS.getAddress(), BasePtr);
1780        EmitCXXAggrDestructorCall(FieldClassDecl->getDestructor(getContext()),
1781                                  Array, BaseAddrPtr);
1782      }
1783      else
1784        EmitCXXDestructorCall(FieldClassDecl->getDestructor(getContext()),
1785                              Dtor_Complete, LHS.getAddress());
1786    } else {
1787      const RecordType *RT =
1788        DD->getAnyBaseClassToDestroy(BaseOrMember)->getAs<RecordType>();
1789      CXXRecordDecl *BaseClassDecl = cast<CXXRecordDecl>(RT->getDecl());
1790      if (BaseClassDecl->hasTrivialDestructor())
1791        continue;
1792      llvm::Value *V = AddressCXXOfBaseClass(LoadCXXThis(),
1793                                             ClassDecl,BaseClassDecl);
1794      EmitCXXDestructorCall(BaseClassDecl->getDestructor(getContext()),
1795                            Dtor_Complete, V);
1796    }
1797  }
1798  if (DD->getNumBaseOrMemberDestructions() || DD->isTrivial())
1799    return;
1800  // Case of destructor synthesis with fields and base classes
1801  // which have non-trivial destructors. They must be destructed in
1802  // reverse order of their construction.
1803  llvm::SmallVector<FieldDecl *, 16> DestructedFields;
1804
1805  for (CXXRecordDecl::field_iterator Field = ClassDecl->field_begin(),
1806       FieldEnd = ClassDecl->field_end();
1807       Field != FieldEnd; ++Field) {
1808    QualType FieldType = getContext().getCanonicalType((*Field)->getType());
1809    if (getContext().getAsConstantArrayType(FieldType))
1810      FieldType = getContext().getBaseElementType(FieldType);
1811    if (const RecordType *RT = FieldType->getAs<RecordType>()) {
1812      CXXRecordDecl *FieldClassDecl = cast<CXXRecordDecl>(RT->getDecl());
1813      if (FieldClassDecl->hasTrivialDestructor())
1814        continue;
1815      DestructedFields.push_back(*Field);
1816    }
1817  }
1818  if (!DestructedFields.empty())
1819    for (int i = DestructedFields.size() -1; i >= 0; --i) {
1820      FieldDecl *Field = DestructedFields[i];
1821      QualType FieldType = Field->getType();
1822      const ConstantArrayType *Array =
1823        getContext().getAsConstantArrayType(FieldType);
1824        if (Array)
1825          FieldType = getContext().getBaseElementType(FieldType);
1826      const RecordType *RT = FieldType->getAs<RecordType>();
1827      CXXRecordDecl *FieldClassDecl = cast<CXXRecordDecl>(RT->getDecl());
1828      llvm::Value *LoadOfThis = LoadCXXThis();
1829      LValue LHS = EmitLValueForField(LoadOfThis, Field, false, 0);
1830      if (Array) {
1831        const llvm::Type *BasePtr = ConvertType(FieldType);
1832        BasePtr = llvm::PointerType::getUnqual(BasePtr);
1833        llvm::Value *BaseAddrPtr =
1834        Builder.CreateBitCast(LHS.getAddress(), BasePtr);
1835        EmitCXXAggrDestructorCall(FieldClassDecl->getDestructor(getContext()),
1836                                  Array, BaseAddrPtr);
1837      }
1838      else
1839        EmitCXXDestructorCall(FieldClassDecl->getDestructor(getContext()),
1840                              Dtor_Complete, LHS.getAddress());
1841    }
1842
1843  llvm::SmallVector<CXXRecordDecl*, 4> DestructedBases;
1844  for (CXXRecordDecl::base_class_const_iterator Base = ClassDecl->bases_begin();
1845       Base != ClassDecl->bases_end(); ++Base) {
1846    // FIXME. copy assignment of virtual base NYI
1847    if (Base->isVirtual())
1848      continue;
1849
1850    CXXRecordDecl *BaseClassDecl
1851      = cast<CXXRecordDecl>(Base->getType()->getAs<RecordType>()->getDecl());
1852    if (BaseClassDecl->hasTrivialDestructor())
1853      continue;
1854    DestructedBases.push_back(BaseClassDecl);
1855  }
1856  if (DestructedBases.empty())
1857    return;
1858  for (int i = DestructedBases.size() -1; i >= 0; --i) {
1859    CXXRecordDecl *BaseClassDecl = DestructedBases[i];
1860    llvm::Value *V = AddressCXXOfBaseClass(LoadCXXThis(),
1861                                           ClassDecl,BaseClassDecl);
1862    EmitCXXDestructorCall(BaseClassDecl->getDestructor(getContext()),
1863                          Dtor_Complete, V);
1864  }
1865}
1866
1867void CodeGenFunction::SynthesizeDefaultDestructor(const CXXDestructorDecl *CD,
1868                                                  const FunctionDecl *FD,
1869                                                  llvm::Function *Fn,
1870                                                  const FunctionArgList &Args) {
1871
1872  const CXXRecordDecl *ClassDecl = cast<CXXRecordDecl>(CD->getDeclContext());
1873  assert(!ClassDecl->hasUserDeclaredDestructor() &&
1874         "SynthesizeDefaultDestructor - destructor has user declaration");
1875  (void) ClassDecl;
1876
1877  StartFunction(FD, FD->getResultType(), Fn, Args, SourceLocation());
1878  EmitDtorEpilogue(CD);
1879  FinishFunction();
1880}
1881