CGCXX.cpp revision a18df0ec71c5c95fb6809d4a80050f7b218f38b5 
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  // A call to a trivial destructor requires no code generation.
182  if (const CXXDestructorDecl *Destructor = dyn_cast<CXXDestructorDecl>(MD))
183    if (Destructor->isTrivial())
184      return RValue::get(0);
185
186  const FunctionProtoType *FPT = MD->getType()->getAsFunctionProtoType();
187
188  CallArgList Args;
189
190  // Push the this ptr.
191  Args.push_back(std::make_pair(RValue::get(This),
192                                MD->getThisType(getContext())));
193
194  // And the rest of the call args
195  EmitCallArgs(Args, FPT, ArgBeg, ArgEnd);
196
197  QualType ResultType = MD->getType()->getAsFunctionType()->getResultType();
198  return EmitCall(CGM.getTypes().getFunctionInfo(ResultType, Args),
199                  Callee, Args, MD);
200}
201
202RValue CodeGenFunction::EmitCXXMemberCallExpr(const CXXMemberCallExpr *CE) {
203  const MemberExpr *ME = cast<MemberExpr>(CE->getCallee());
204  const CXXMethodDecl *MD = cast<CXXMethodDecl>(ME->getMemberDecl());
205
206  const FunctionProtoType *FPT = MD->getType()->getAsFunctionProtoType();
207
208  const llvm::Type *Ty =
209    CGM.getTypes().GetFunctionType(CGM.getTypes().getFunctionInfo(MD),
210                                   FPT->isVariadic());
211  llvm::Value *This;
212
213  if (ME->isArrow())
214    This = EmitScalarExpr(ME->getBase());
215  else {
216    LValue BaseLV = EmitLValue(ME->getBase());
217    This = BaseLV.getAddress();
218  }
219
220  // C++ [class.virtual]p12:
221  //   Explicit qualification with the scope operator (5.1) suppresses the
222  //   virtual call mechanism.
223  llvm::Value *Callee;
224  if (MD->isVirtual() && !ME->hasQualifier())
225    Callee = BuildVirtualCall(MD, This, Ty);
226  else if (const CXXDestructorDecl *Destructor
227             = dyn_cast<CXXDestructorDecl>(MD))
228    Callee = CGM.GetAddrOfFunction(GlobalDecl(Destructor, Dtor_Complete), Ty);
229  else
230    Callee = CGM.GetAddrOfFunction(GlobalDecl(MD), Ty);
231
232  return EmitCXXMemberCall(MD, Callee, This,
233                           CE->arg_begin(), CE->arg_end());
234}
235
236RValue
237CodeGenFunction::EmitCXXOperatorMemberCallExpr(const CXXOperatorCallExpr *E,
238                                               const CXXMethodDecl *MD) {
239  assert(MD->isInstance() &&
240         "Trying to emit a member call expr on a static method!");
241
242  if (MD->isCopyAssignment()) {
243    const CXXRecordDecl *ClassDecl = cast<CXXRecordDecl>(MD->getDeclContext());
244    if (ClassDecl->hasTrivialCopyAssignment()) {
245      assert(!ClassDecl->hasUserDeclaredCopyAssignment() &&
246             "EmitCXXOperatorMemberCallExpr - user declared copy assignment");
247      llvm::Value *This = EmitLValue(E->getArg(0)).getAddress();
248      llvm::Value *Src = EmitLValue(E->getArg(1)).getAddress();
249      QualType Ty = E->getType();
250      EmitAggregateCopy(This, Src, Ty);
251      return RValue::get(This);
252    }
253  }
254
255  const FunctionProtoType *FPT = MD->getType()->getAsFunctionProtoType();
256  const llvm::Type *Ty =
257    CGM.getTypes().GetFunctionType(CGM.getTypes().getFunctionInfo(MD),
258                                   FPT->isVariadic());
259  llvm::Constant *Callee = CGM.GetAddrOfFunction(GlobalDecl(MD), Ty);
260
261  llvm::Value *This = EmitLValue(E->getArg(0)).getAddress();
262
263  return EmitCXXMemberCall(MD, Callee, This,
264                           E->arg_begin() + 1, E->arg_end());
265}
266
267RValue
268CodeGenFunction::EmitCXXFunctionalCastExpr(const CXXFunctionalCastExpr *E) {
269  assert((E->getCastKind() == CastExpr::CK_UserDefinedConversion) &&
270         "EmitCXXFunctionalCastExpr - called with wrong cast");
271
272  CXXMethodDecl *MD = E->getTypeConversionMethod();
273  assert(MD && "EmitCXXFunctionalCastExpr - null conversion method");
274  assert(isa<CXXConversionDecl>(MD) && "EmitCXXFunctionalCastExpr - not"
275         " method decl");
276  const FunctionProtoType *FPT = MD->getType()->getAsFunctionProtoType();
277
278  const llvm::Type *Ty =
279    CGM.getTypes().GetFunctionType(CGM.getTypes().getFunctionInfo(MD),
280                                   FPT->isVariadic());
281  llvm::Constant *Callee = CGM.GetAddrOfFunction(GlobalDecl(MD), Ty);
282  llvm::Value *This = EmitLValue(E->getSubExpr()).getAddress();
283  RValue RV = EmitCXXMemberCall(MD, Callee, This, 0, 0);
284  if (RV.isAggregate())
285    RV = RValue::get(RV.getAggregateAddr());
286  return RV;
287}
288
289llvm::Value *CodeGenFunction::LoadCXXThis() {
290  assert(isa<CXXMethodDecl>(CurFuncDecl) &&
291         "Must be in a C++ member function decl to load 'this'");
292  assert(cast<CXXMethodDecl>(CurFuncDecl)->isInstance() &&
293         "Must be in a C++ member function decl to load 'this'");
294
295  // FIXME: What if we're inside a block?
296  // ans: See how CodeGenFunction::LoadObjCSelf() uses
297  // CodeGenFunction::BlockForwardSelf() for how to do this.
298  return Builder.CreateLoad(LocalDeclMap[CXXThisDecl], "this");
299}
300
301static bool
302GetNestedPaths(llvm::SmallVectorImpl<const CXXRecordDecl *> &NestedBasePaths,
303               const CXXRecordDecl *ClassDecl,
304               const CXXRecordDecl *BaseClassDecl) {
305  for (CXXRecordDecl::base_class_const_iterator i = ClassDecl->bases_begin(),
306      e = ClassDecl->bases_end(); i != e; ++i) {
307    if (i->isVirtual())
308      continue;
309    const CXXRecordDecl *Base =
310      cast<CXXRecordDecl>(i->getType()->getAs<RecordType>()->getDecl());
311    if (Base == BaseClassDecl) {
312      NestedBasePaths.push_back(BaseClassDecl);
313      return true;
314    }
315  }
316  // BaseClassDecl not an immediate base of ClassDecl.
317  for (CXXRecordDecl::base_class_const_iterator i = ClassDecl->bases_begin(),
318       e = ClassDecl->bases_end(); i != e; ++i) {
319    if (i->isVirtual())
320      continue;
321    const CXXRecordDecl *Base =
322      cast<CXXRecordDecl>(i->getType()->getAs<RecordType>()->getDecl());
323    if (GetNestedPaths(NestedBasePaths, Base, BaseClassDecl)) {
324      NestedBasePaths.push_back(Base);
325      return true;
326    }
327  }
328  return false;
329}
330
331llvm::Value *CodeGenFunction::AddressCXXOfBaseClass(llvm::Value *BaseValue,
332                                          const CXXRecordDecl *ClassDecl,
333                                          const CXXRecordDecl *BaseClassDecl) {
334  if (ClassDecl == BaseClassDecl)
335    return BaseValue;
336
337  llvm::Type *I8Ptr = llvm::PointerType::getUnqual(llvm::Type::getInt8Ty(VMContext));
338  llvm::SmallVector<const CXXRecordDecl *, 16> NestedBasePaths;
339  GetNestedPaths(NestedBasePaths, ClassDecl, BaseClassDecl);
340  assert(NestedBasePaths.size() > 0 &&
341         "AddressCXXOfBaseClass - inheritence path failed");
342  NestedBasePaths.push_back(ClassDecl);
343  uint64_t Offset = 0;
344
345  // Accessing a member of the base class. Must add delata to
346  // the load of 'this'.
347  for (unsigned i = NestedBasePaths.size()-1; i > 0; i--) {
348    const CXXRecordDecl *DerivedClass = NestedBasePaths[i];
349    const CXXRecordDecl *BaseClass = NestedBasePaths[i-1];
350    const ASTRecordLayout &Layout =
351      getContext().getASTRecordLayout(DerivedClass);
352    Offset += Layout.getBaseClassOffset(BaseClass) / 8;
353  }
354  llvm::Value *OffsetVal =
355    llvm::ConstantInt::get(
356                  CGM.getTypes().ConvertType(CGM.getContext().LongTy), Offset);
357  BaseValue = Builder.CreateBitCast(BaseValue, I8Ptr);
358  BaseValue = Builder.CreateGEP(BaseValue, OffsetVal, "add.ptr");
359  QualType BTy =
360    getContext().getCanonicalType(
361      getContext().getTypeDeclType(const_cast<CXXRecordDecl*>(BaseClassDecl)));
362  const llvm::Type *BasePtr = ConvertType(BTy);
363  BasePtr = llvm::PointerType::getUnqual(BasePtr);
364  BaseValue = Builder.CreateBitCast(BaseValue, BasePtr);
365  return BaseValue;
366}
367
368/// EmitCXXAggrConstructorCall - This routine essentially creates a (nested)
369/// for-loop to call the default constructor on individual members of the
370/// array. 'Array' is the array type, 'This' is llvm pointer of the start
371/// of the array and 'D' is the default costructor Decl for elements of the
372/// array. It is assumed that all relevant checks have been made by the
373/// caller.
374void
375CodeGenFunction::EmitCXXAggrConstructorCall(const CXXConstructorDecl *D,
376                                            const ArrayType *Array,
377                                            llvm::Value *This) {
378  const ConstantArrayType *CA = dyn_cast<ConstantArrayType>(Array);
379  assert(CA && "Do we support VLA for construction ?");
380
381  // Create a temporary for the loop index and initialize it with 0.
382  llvm::Value *IndexPtr = CreateTempAlloca(llvm::Type::getInt64Ty(VMContext),
383                                           "loop.index");
384  llvm::Value* zeroConstant =
385    llvm::Constant::getNullValue(llvm::Type::getInt64Ty(VMContext));
386  Builder.CreateStore(zeroConstant, IndexPtr, false);
387
388  // Start the loop with a block that tests the condition.
389  llvm::BasicBlock *CondBlock = createBasicBlock("for.cond");
390  llvm::BasicBlock *AfterFor = createBasicBlock("for.end");
391
392  EmitBlock(CondBlock);
393
394  llvm::BasicBlock *ForBody = createBasicBlock("for.body");
395
396  // Generate: if (loop-index < number-of-elements fall to the loop body,
397  // otherwise, go to the block after the for-loop.
398  uint64_t NumElements = getContext().getConstantArrayElementCount(CA);
399  llvm::Value * NumElementsPtr =
400    llvm::ConstantInt::get(llvm::Type::getInt64Ty(VMContext), NumElements);
401  llvm::Value *Counter = Builder.CreateLoad(IndexPtr);
402  llvm::Value *IsLess = Builder.CreateICmpULT(Counter, NumElementsPtr,
403                                              "isless");
404  // If the condition is true, execute the body.
405  Builder.CreateCondBr(IsLess, ForBody, AfterFor);
406
407  EmitBlock(ForBody);
408
409  llvm::BasicBlock *ContinueBlock = createBasicBlock("for.inc");
410  // Inside the loop body, emit the constructor call on the array element.
411  Counter = Builder.CreateLoad(IndexPtr);
412  llvm::Value *Address = Builder.CreateInBoundsGEP(This, Counter, "arrayidx");
413  EmitCXXConstructorCall(D, Ctor_Complete, Address, 0, 0);
414
415  EmitBlock(ContinueBlock);
416
417  // Emit the increment of the loop counter.
418  llvm::Value *NextVal = llvm::ConstantInt::get(Counter->getType(), 1);
419  Counter = Builder.CreateLoad(IndexPtr);
420  NextVal = Builder.CreateAdd(Counter, NextVal, "inc");
421  Builder.CreateStore(NextVal, IndexPtr, false);
422
423  // Finally, branch back up to the condition for the next iteration.
424  EmitBranch(CondBlock);
425
426  // Emit the fall-through block.
427  EmitBlock(AfterFor, true);
428}
429
430/// EmitCXXAggrDestructorCall - calls the default destructor on array
431/// elements in reverse order of construction.
432void
433CodeGenFunction::EmitCXXAggrDestructorCall(const CXXDestructorDecl *D,
434                                           const ArrayType *Array,
435                                           llvm::Value *This) {
436  const ConstantArrayType *CA = dyn_cast<ConstantArrayType>(Array);
437  assert(CA && "Do we support VLA for destruction ?");
438  llvm::Value *One = llvm::ConstantInt::get(llvm::Type::getInt64Ty(VMContext),
439                                            1);
440  uint64_t ElementCount = getContext().getConstantArrayElementCount(CA);
441  // Create a temporary for the loop index and initialize it with count of
442  // array elements.
443  llvm::Value *IndexPtr = CreateTempAlloca(llvm::Type::getInt64Ty(VMContext),
444                                           "loop.index");
445  // Index = ElementCount;
446  llvm::Value* UpperCount =
447    llvm::ConstantInt::get(llvm::Type::getInt64Ty(VMContext), ElementCount);
448  Builder.CreateStore(UpperCount, IndexPtr, false);
449
450  // Start the loop with a block that tests the condition.
451  llvm::BasicBlock *CondBlock = createBasicBlock("for.cond");
452  llvm::BasicBlock *AfterFor = createBasicBlock("for.end");
453
454  EmitBlock(CondBlock);
455
456  llvm::BasicBlock *ForBody = createBasicBlock("for.body");
457
458  // Generate: if (loop-index != 0 fall to the loop body,
459  // otherwise, go to the block after the for-loop.
460  llvm::Value* zeroConstant =
461    llvm::Constant::getNullValue(llvm::Type::getInt64Ty(VMContext));
462  llvm::Value *Counter = Builder.CreateLoad(IndexPtr);
463  llvm::Value *IsNE = Builder.CreateICmpNE(Counter, zeroConstant,
464                                            "isne");
465  // If the condition is true, execute the body.
466  Builder.CreateCondBr(IsNE, ForBody, AfterFor);
467
468  EmitBlock(ForBody);
469
470  llvm::BasicBlock *ContinueBlock = createBasicBlock("for.inc");
471  // Inside the loop body, emit the constructor call on the array element.
472  Counter = Builder.CreateLoad(IndexPtr);
473  Counter = Builder.CreateSub(Counter, One);
474  llvm::Value *Address = Builder.CreateInBoundsGEP(This, Counter, "arrayidx");
475  EmitCXXDestructorCall(D, Dtor_Complete, Address);
476
477  EmitBlock(ContinueBlock);
478
479  // Emit the decrement of the loop counter.
480  Counter = Builder.CreateLoad(IndexPtr);
481  Counter = Builder.CreateSub(Counter, One, "dec");
482  Builder.CreateStore(Counter, IndexPtr, false);
483
484  // Finally, branch back up to the condition for the next iteration.
485  EmitBranch(CondBlock);
486
487  // Emit the fall-through block.
488  EmitBlock(AfterFor, true);
489}
490
491void
492CodeGenFunction::EmitCXXConstructorCall(const CXXConstructorDecl *D,
493                                        CXXCtorType Type,
494                                        llvm::Value *This,
495                                        CallExpr::const_arg_iterator ArgBeg,
496                                        CallExpr::const_arg_iterator ArgEnd) {
497  if (D->isCopyConstructor(getContext())) {
498    const CXXRecordDecl *ClassDecl = cast<CXXRecordDecl>(D->getDeclContext());
499    if (ClassDecl->hasTrivialCopyConstructor()) {
500      assert(!ClassDecl->hasUserDeclaredCopyConstructor() &&
501             "EmitCXXConstructorCall - user declared copy constructor");
502      const Expr *E = (*ArgBeg);
503      QualType Ty = E->getType();
504      llvm::Value *Src = EmitLValue(E).getAddress();
505      EmitAggregateCopy(This, Src, Ty);
506      return;
507    }
508  }
509
510  llvm::Value *Callee = CGM.GetAddrOfCXXConstructor(D, Type);
511
512  EmitCXXMemberCall(D, Callee, This, ArgBeg, ArgEnd);
513}
514
515void CodeGenFunction::EmitCXXDestructorCall(const CXXDestructorDecl *D,
516                                            CXXDtorType Type,
517                                            llvm::Value *This) {
518  llvm::Value *Callee = CGM.GetAddrOfCXXDestructor(D, Type);
519
520  EmitCXXMemberCall(D, Callee, This, 0, 0);
521}
522
523void
524CodeGenFunction::EmitCXXConstructExpr(llvm::Value *Dest,
525                                      const CXXConstructExpr *E) {
526  assert(Dest && "Must have a destination!");
527
528  const CXXRecordDecl *RD =
529  cast<CXXRecordDecl>(E->getType()->getAs<RecordType>()->getDecl());
530  if (RD->hasTrivialConstructor())
531    return;
532
533  // Code gen optimization to eliminate copy constructor and return
534  // its first argument instead.
535  if (getContext().getLangOptions().ElideConstructors && E->isElidable()) {
536    CXXConstructExpr::const_arg_iterator i = E->arg_begin();
537    EmitAggExpr((*i), Dest, false);
538    return;
539  }
540  // Call the constructor.
541  EmitCXXConstructorCall(E->getConstructor(), Ctor_Complete, Dest,
542                         E->arg_begin(), E->arg_end());
543}
544
545llvm::Value *CodeGenFunction::EmitCXXNewExpr(const CXXNewExpr *E) {
546  if (E->isArray()) {
547    ErrorUnsupported(E, "new[] expression");
548    return llvm::UndefValue::get(ConvertType(E->getType()));
549  }
550
551  QualType AllocType = E->getAllocatedType();
552  FunctionDecl *NewFD = E->getOperatorNew();
553  const FunctionProtoType *NewFTy = NewFD->getType()->getAsFunctionProtoType();
554
555  CallArgList NewArgs;
556
557  // The allocation size is the first argument.
558  QualType SizeTy = getContext().getSizeType();
559  llvm::Value *AllocSize =
560    llvm::ConstantInt::get(ConvertType(SizeTy),
561                           getContext().getTypeSize(AllocType) / 8);
562
563  NewArgs.push_back(std::make_pair(RValue::get(AllocSize), SizeTy));
564
565  // Emit the rest of the arguments.
566  // FIXME: Ideally, this should just use EmitCallArgs.
567  CXXNewExpr::const_arg_iterator NewArg = E->placement_arg_begin();
568
569  // First, use the types from the function type.
570  // We start at 1 here because the first argument (the allocation size)
571  // has already been emitted.
572  for (unsigned i = 1, e = NewFTy->getNumArgs(); i != e; ++i, ++NewArg) {
573    QualType ArgType = NewFTy->getArgType(i);
574
575    assert(getContext().getCanonicalType(ArgType.getNonReferenceType()).
576           getTypePtr() ==
577           getContext().getCanonicalType(NewArg->getType()).getTypePtr() &&
578           "type mismatch in call argument!");
579
580    NewArgs.push_back(std::make_pair(EmitCallArg(*NewArg, ArgType),
581                                     ArgType));
582
583  }
584
585  // Either we've emitted all the call args, or we have a call to a
586  // variadic function.
587  assert((NewArg == E->placement_arg_end() || NewFTy->isVariadic()) &&
588         "Extra arguments in non-variadic function!");
589
590  // If we still have any arguments, emit them using the type of the argument.
591  for (CXXNewExpr::const_arg_iterator NewArgEnd = E->placement_arg_end();
592       NewArg != NewArgEnd; ++NewArg) {
593    QualType ArgType = NewArg->getType();
594    NewArgs.push_back(std::make_pair(EmitCallArg(*NewArg, ArgType),
595                                     ArgType));
596  }
597
598  // Emit the call to new.
599  RValue RV =
600    EmitCall(CGM.getTypes().getFunctionInfo(NewFTy->getResultType(), NewArgs),
601             CGM.GetAddrOfFunction(GlobalDecl(NewFD)),
602             NewArgs, NewFD);
603
604  // If an allocation function is declared with an empty exception specification
605  // it returns null to indicate failure to allocate storage. [expr.new]p13.
606  // (We don't need to check for null when there's no new initializer and
607  // we're allocating a POD type).
608  bool NullCheckResult = NewFTy->hasEmptyExceptionSpec() &&
609    !(AllocType->isPODType() && !E->hasInitializer());
610
611  llvm::BasicBlock *NewNull = 0;
612  llvm::BasicBlock *NewNotNull = 0;
613  llvm::BasicBlock *NewEnd = 0;
614
615  llvm::Value *NewPtr = RV.getScalarVal();
616
617  if (NullCheckResult) {
618    NewNull = createBasicBlock("new.null");
619    NewNotNull = createBasicBlock("new.notnull");
620    NewEnd = createBasicBlock("new.end");
621
622    llvm::Value *IsNull =
623      Builder.CreateICmpEQ(NewPtr,
624                           llvm::Constant::getNullValue(NewPtr->getType()),
625                           "isnull");
626
627    Builder.CreateCondBr(IsNull, NewNull, NewNotNull);
628    EmitBlock(NewNotNull);
629  }
630
631  NewPtr = Builder.CreateBitCast(NewPtr, ConvertType(E->getType()));
632
633  if (AllocType->isPODType()) {
634    if (E->getNumConstructorArgs() > 0) {
635      assert(E->getNumConstructorArgs() == 1 &&
636             "Can only have one argument to initializer of POD type.");
637
638      const Expr *Init = E->getConstructorArg(0);
639
640      if (!hasAggregateLLVMType(AllocType))
641        Builder.CreateStore(EmitScalarExpr(Init), NewPtr);
642      else if (AllocType->isAnyComplexType())
643        EmitComplexExprIntoAddr(Init, NewPtr, AllocType.isVolatileQualified());
644      else
645        EmitAggExpr(Init, NewPtr, AllocType.isVolatileQualified());
646    }
647  } else {
648    // Call the constructor.
649    CXXConstructorDecl *Ctor = E->getConstructor();
650
651    EmitCXXConstructorCall(Ctor, Ctor_Complete, NewPtr,
652                           E->constructor_arg_begin(),
653                           E->constructor_arg_end());
654  }
655
656  if (NullCheckResult) {
657    Builder.CreateBr(NewEnd);
658    EmitBlock(NewNull);
659    Builder.CreateBr(NewEnd);
660    EmitBlock(NewEnd);
661
662    llvm::PHINode *PHI = Builder.CreatePHI(NewPtr->getType());
663    PHI->reserveOperandSpace(2);
664    PHI->addIncoming(NewPtr, NewNotNull);
665    PHI->addIncoming(llvm::Constant::getNullValue(NewPtr->getType()), NewNull);
666
667    NewPtr = PHI;
668  }
669
670  return NewPtr;
671}
672
673void CodeGenFunction::EmitCXXDeleteExpr(const CXXDeleteExpr *E) {
674  if (E->isArrayForm()) {
675    ErrorUnsupported(E, "delete[] expression");
676    return;
677  };
678
679  QualType DeleteTy =
680    E->getArgument()->getType()->getAs<PointerType>()->getPointeeType();
681
682  llvm::Value *Ptr = EmitScalarExpr(E->getArgument());
683
684  // Null check the pointer.
685  llvm::BasicBlock *DeleteNotNull = createBasicBlock("delete.notnull");
686  llvm::BasicBlock *DeleteEnd = createBasicBlock("delete.end");
687
688  llvm::Value *IsNull =
689    Builder.CreateICmpEQ(Ptr, llvm::Constant::getNullValue(Ptr->getType()),
690                         "isnull");
691
692  Builder.CreateCondBr(IsNull, DeleteEnd, DeleteNotNull);
693  EmitBlock(DeleteNotNull);
694
695  // Call the destructor if necessary.
696  if (const RecordType *RT = DeleteTy->getAs<RecordType>()) {
697    if (CXXRecordDecl *RD = dyn_cast<CXXRecordDecl>(RT->getDecl())) {
698      if (!RD->hasTrivialDestructor()) {
699        const CXXDestructorDecl *Dtor = RD->getDestructor(getContext());
700        if (Dtor->isVirtual()) {
701          ErrorUnsupported(E, "delete expression with virtual destructor");
702          return;
703        }
704
705        EmitCXXDestructorCall(Dtor, Dtor_Complete, Ptr);
706      }
707    }
708  }
709
710  // Call delete.
711  FunctionDecl *DeleteFD = E->getOperatorDelete();
712  const FunctionProtoType *DeleteFTy =
713    DeleteFD->getType()->getAsFunctionProtoType();
714
715  CallArgList DeleteArgs;
716
717  QualType ArgTy = DeleteFTy->getArgType(0);
718  llvm::Value *DeletePtr = Builder.CreateBitCast(Ptr, ConvertType(ArgTy));
719  DeleteArgs.push_back(std::make_pair(RValue::get(DeletePtr), ArgTy));
720
721  // Emit the call to delete.
722  EmitCall(CGM.getTypes().getFunctionInfo(DeleteFTy->getResultType(),
723                                          DeleteArgs),
724           CGM.GetAddrOfFunction(GlobalDecl(DeleteFD)),
725           DeleteArgs, DeleteFD);
726
727  EmitBlock(DeleteEnd);
728}
729
730void CodeGenModule::EmitCXXConstructors(const CXXConstructorDecl *D) {
731  EmitGlobal(GlobalDecl(D, Ctor_Complete));
732  EmitGlobal(GlobalDecl(D, Ctor_Base));
733}
734
735void CodeGenModule::EmitCXXConstructor(const CXXConstructorDecl *D,
736                                       CXXCtorType Type) {
737
738  llvm::Function *Fn = GetAddrOfCXXConstructor(D, Type);
739
740  CodeGenFunction(*this).GenerateCode(D, Fn);
741
742  SetFunctionDefinitionAttributes(D, Fn);
743  SetLLVMFunctionAttributesForDefinition(D, Fn);
744}
745
746llvm::Function *
747CodeGenModule::GetAddrOfCXXConstructor(const CXXConstructorDecl *D,
748                                       CXXCtorType Type) {
749  const llvm::FunctionType *FTy =
750    getTypes().GetFunctionType(getTypes().getFunctionInfo(D), false);
751
752  const char *Name = getMangledCXXCtorName(D, Type);
753  return cast<llvm::Function>(
754                      GetOrCreateLLVMFunction(Name, FTy, GlobalDecl(D, Type)));
755}
756
757const char *CodeGenModule::getMangledCXXCtorName(const CXXConstructorDecl *D,
758                                                 CXXCtorType Type) {
759  llvm::SmallString<256> Name;
760  llvm::raw_svector_ostream Out(Name);
761  mangleCXXCtor(D, Type, Context, Out);
762
763  Name += '\0';
764  return UniqueMangledName(Name.begin(), Name.end());
765}
766
767void CodeGenModule::EmitCXXDestructors(const CXXDestructorDecl *D) {
768  EmitCXXDestructor(D, Dtor_Complete);
769  EmitCXXDestructor(D, Dtor_Base);
770}
771
772void CodeGenModule::EmitCXXDestructor(const CXXDestructorDecl *D,
773                                      CXXDtorType Type) {
774  llvm::Function *Fn = GetAddrOfCXXDestructor(D, Type);
775
776  CodeGenFunction(*this).GenerateCode(D, Fn);
777
778  SetFunctionDefinitionAttributes(D, Fn);
779  SetLLVMFunctionAttributesForDefinition(D, Fn);
780}
781
782llvm::Function *
783CodeGenModule::GetAddrOfCXXDestructor(const CXXDestructorDecl *D,
784                                      CXXDtorType Type) {
785  const llvm::FunctionType *FTy =
786    getTypes().GetFunctionType(getTypes().getFunctionInfo(D), false);
787
788  const char *Name = getMangledCXXDtorName(D, Type);
789  return cast<llvm::Function>(
790                      GetOrCreateLLVMFunction(Name, FTy, GlobalDecl(D, Type)));
791}
792
793const char *CodeGenModule::getMangledCXXDtorName(const CXXDestructorDecl *D,
794                                                 CXXDtorType Type) {
795  llvm::SmallString<256> Name;
796  llvm::raw_svector_ostream Out(Name);
797  mangleCXXDtor(D, Type, Context, Out);
798
799  Name += '\0';
800  return UniqueMangledName(Name.begin(), Name.end());
801}
802
803llvm::Constant *CodeGenModule::GenerateRtti(const CXXRecordDecl *RD) {
804  llvm::Type *Ptr8Ty;
805  Ptr8Ty = llvm::PointerType::get(llvm::Type::getInt8Ty(VMContext), 0);
806  llvm::Constant *Rtti = llvm::Constant::getNullValue(Ptr8Ty);
807
808  if (!getContext().getLangOptions().Rtti)
809    return Rtti;
810
811  llvm::SmallString<256> OutName;
812  llvm::raw_svector_ostream Out(OutName);
813  QualType ClassTy;
814  ClassTy = getContext().getTagDeclType(RD);
815  mangleCXXRtti(ClassTy, getContext(), Out);
816  llvm::GlobalVariable::LinkageTypes linktype;
817  linktype = llvm::GlobalValue::WeakAnyLinkage;
818  std::vector<llvm::Constant *> info;
819  // assert(0 && "FIXME: implement rtti descriptor");
820  // FIXME: descriptor
821  info.push_back(llvm::Constant::getNullValue(Ptr8Ty));
822  // assert(0 && "FIXME: implement rtti ts");
823  // FIXME: TS
824  info.push_back(llvm::Constant::getNullValue(Ptr8Ty));
825
826  llvm::Constant *C;
827  llvm::ArrayType *type = llvm::ArrayType::get(Ptr8Ty, info.size());
828  C = llvm::ConstantArray::get(type, info);
829  Rtti = new llvm::GlobalVariable(getModule(), type, true, linktype, C,
830                                  Out.str());
831  Rtti = llvm::ConstantExpr::getBitCast(Rtti, Ptr8Ty);
832  return Rtti;
833}
834
835class VtableBuilder {
836public:
837  /// Index_t - Vtable index type.
838  typedef uint64_t Index_t;
839private:
840  std::vector<llvm::Constant *> &methods;
841  std::vector<llvm::Constant *> submethods;
842  llvm::Type *Ptr8Ty;
843  /// Class - The most derived class that this vtable is being built for.
844  const CXXRecordDecl *Class;
845  /// BLayout - Layout for the most derived class that this vtable is being
846  /// built for.
847  const ASTRecordLayout &BLayout;
848  llvm::SmallSet<const CXXRecordDecl *, 32> IndirectPrimary;
849  llvm::SmallSet<const CXXRecordDecl *, 32> SeenVBase;
850  llvm::Constant *rtti;
851  llvm::LLVMContext &VMContext;
852  CodeGenModule &CGM;  // Per-module state.
853  /// Index - Maps a method decl into a vtable index.  Useful for virtual
854  /// dispatch codegen.
855  llvm::DenseMap<const CXXMethodDecl *, Index_t> Index;
856  llvm::DenseMap<const CXXMethodDecl *, Index_t> VCall;
857  llvm::DenseMap<const CXXMethodDecl *, Index_t> VCallOffset;
858  typedef llvm::DenseMap<const CXXMethodDecl *,
859                         std::pair<Index_t, Index_t> > Thunks_t;
860  Thunks_t Thunks;
861  std::vector<Index_t> VCalls;
862  typedef CXXRecordDecl::method_iterator method_iter;
863  // FIXME: Linkage should follow vtable
864  const bool Extern;
865  const uint32_t LLVMPointerWidth;
866  Index_t extra;
867public:
868  VtableBuilder(std::vector<llvm::Constant *> &meth,
869                const CXXRecordDecl *c,
870                CodeGenModule &cgm)
871    : methods(meth), Class(c), BLayout(cgm.getContext().getASTRecordLayout(c)),
872      rtti(cgm.GenerateRtti(c)), VMContext(cgm.getModule().getContext()),
873      CGM(cgm), Extern(true),
874      LLVMPointerWidth(cgm.getContext().Target.getPointerWidth(0)) {
875    Ptr8Ty = llvm::PointerType::get(llvm::Type::getInt8Ty(VMContext), 0);
876  }
877
878  llvm::DenseMap<const CXXMethodDecl *, Index_t> &getIndex() { return Index; }
879
880  llvm::Constant *wrap(Index_t i) {
881    llvm::Constant *m;
882    m = llvm::ConstantInt::get(llvm::Type::getInt64Ty(VMContext), i);
883    return llvm::ConstantExpr::getIntToPtr(m, Ptr8Ty);
884  }
885
886  llvm::Constant *wrap(llvm::Constant *m) {
887    return llvm::ConstantExpr::getBitCast(m, Ptr8Ty);
888  }
889
890  void GenerateVBaseOffsets(std::vector<llvm::Constant *> &offsets,
891                            const CXXRecordDecl *RD, uint64_t Offset) {
892    for (CXXRecordDecl::base_class_const_iterator i =RD->bases_begin(),
893           e = RD->bases_end(); i != e; ++i) {
894      const CXXRecordDecl *Base =
895        cast<CXXRecordDecl>(i->getType()->getAs<RecordType>()->getDecl());
896      if (i->isVirtual() && !SeenVBase.count(Base)) {
897        SeenVBase.insert(Base);
898        int64_t BaseOffset = -(Offset/8) + BLayout.getVBaseClassOffset(Base)/8;
899        llvm::Constant *m = wrap(BaseOffset);
900        m = wrap((0?700:0) + BaseOffset);
901        offsets.push_back(m);
902      }
903      GenerateVBaseOffsets(offsets, Base, Offset);
904    }
905  }
906
907  void StartNewTable() {
908    SeenVBase.clear();
909  }
910
911  bool OverrideMethod(const CXXMethodDecl *MD, llvm::Constant *m,
912                      bool MorallyVirtual, Index_t Offset,
913                      std::vector<llvm::Constant *> &submethods,
914                      Index_t AddressPoint) {
915    typedef CXXMethodDecl::method_iterator meth_iter;
916
917    // FIXME: Don't like the nested loops.  For very large inheritance
918    // heirarchies we could have a table on the side with the final overridder
919    // and just replace each instance of an overridden method once.  Would be
920    // nice to measure the cost/benefit on real code.
921
922    for (meth_iter mi = MD->begin_overridden_methods(),
923           e = MD->end_overridden_methods();
924         mi != e; ++mi) {
925      const CXXMethodDecl *OMD = *mi;
926      llvm::Constant *om;
927      om = CGM.GetAddrOfFunction(GlobalDecl(OMD), Ptr8Ty);
928      om = llvm::ConstantExpr::getBitCast(om, Ptr8Ty);
929
930      for (Index_t i = AddressPoint, e = submethods.size();
931           i != e; ++i) {
932        // FIXME: begin_overridden_methods might be too lax, covariance */
933        if (submethods[i] != om)
934          continue;
935        submethods[i] = m;
936        Index[MD] = i - AddressPoint;
937
938        Thunks.erase(OMD);
939        if (MorallyVirtual) {
940          VCallOffset[MD] = Offset/8;
941          Index_t &idx = VCall[OMD];
942          if (idx == 0) {
943            idx = VCalls.size()+1;
944            VCalls.push_back(0);
945          }
946          VCalls[idx] = Offset/8 - VCallOffset[OMD];
947          VCall[MD] = idx;
948          // FIXME: 0?
949          Thunks[MD] = std::make_pair(0, -((idx+extra+2)*LLVMPointerWidth/8));
950          return true;
951        }
952#if 0
953        // FIXME: finish off
954        int64_t O = VCallOffset[OMD] - Offset/8;
955        if (O) {
956          Thunks[MD] = std::make_pair(O, 0);
957        }
958#endif
959        return true;
960      }
961    }
962
963    return false;
964  }
965
966  void InstallThunks(Index_t AddressPoint) {
967    for (Thunks_t::iterator i = Thunks.begin(), e = Thunks.end();
968         i != e; ++i) {
969      const CXXMethodDecl *MD = i->first;
970      Index_t idx = Index[MD];
971      Index_t nv_O = i->second.first;
972      Index_t v_O = i->second.second;
973      methods[AddressPoint + idx] = CGM.BuildThunk(MD, Extern, nv_O, v_O);
974    }
975    Thunks.clear();
976  }
977
978  void OverrideMethods(const CXXRecordDecl *RD, Index_t AddressPoint,
979                       bool MorallyVirtual, Index_t Offset) {
980    for (method_iter mi = RD->method_begin(), me = RD->method_end(); mi != me;
981         ++mi)
982      if (mi->isVirtual()) {
983        const CXXMethodDecl *MD = *mi;
984        llvm::Constant *m = wrap(CGM.GetAddrOfFunction(GlobalDecl(MD), Ptr8Ty));
985        OverrideMethod(MD, m, MorallyVirtual, Offset, methods, AddressPoint);
986      }
987  }
988
989  void AddMethod(const CXXMethodDecl *MD, bool MorallyVirtual, Index_t Offset) {
990    llvm::Constant *m = wrap(CGM.GetAddrOfFunction(GlobalDecl(MD), Ptr8Ty));
991    // If we can find a previously allocated slot for this, reuse it.
992    if (OverrideMethod(MD, m, MorallyVirtual, Offset, submethods, 0))
993      return;
994
995    // else allocate a new slot.
996    Index[MD] = submethods.size();
997    if (MorallyVirtual) {
998      VCallOffset[MD] = Offset/8;
999      Index_t &idx = VCall[MD];
1000      // Allocate the first one, after that, we reuse the previous one.
1001      if (idx == 0) {
1002        idx = VCalls.size()+1;
1003        VCalls.push_back(0);
1004      }
1005    }
1006    submethods.push_back(m);
1007  }
1008
1009  void AddMethods(const CXXRecordDecl *RD, bool MorallyVirtual,
1010                  Index_t Offset) {
1011    for (method_iter mi = RD->method_begin(), me = RD->method_end(); mi != me;
1012         ++mi)
1013      if (mi->isVirtual())
1014        AddMethod(*mi, MorallyVirtual, Offset);
1015  }
1016
1017  void NonVirtualBases(const CXXRecordDecl *RD, const ASTRecordLayout &Layout,
1018                       const CXXRecordDecl *PrimaryBase,
1019                       bool PrimaryBaseWasVirtual, bool MorallyVirtual,
1020                       int64_t Offset) {
1021    for (CXXRecordDecl::base_class_const_iterator i = RD->bases_begin(),
1022           e = RD->bases_end(); i != e; ++i) {
1023      if (i->isVirtual())
1024        continue;
1025      const CXXRecordDecl *Base =
1026        cast<CXXRecordDecl>(i->getType()->getAs<RecordType>()->getDecl());
1027      if (Base != PrimaryBase || PrimaryBaseWasVirtual) {
1028        uint64_t o = Offset + Layout.getBaseClassOffset(Base);
1029        StartNewTable();
1030        Index_t AP;
1031        AP = GenerateVtableForBase(Base, MorallyVirtual, o, false, RD);
1032        OverrideMethods(RD, AP, MorallyVirtual, o);
1033        InstallThunks(AP);
1034      }
1035    }
1036  }
1037
1038  Index_t end(const CXXRecordDecl *RD, std::vector<llvm::Constant *> &offsets,
1039              const ASTRecordLayout &Layout,
1040              const CXXRecordDecl *PrimaryBase,
1041              bool PrimaryBaseWasVirtual, bool MorallyVirtual,
1042              int64_t Offset, bool ForVirtualBase) {
1043    StartNewTable();
1044    extra = 0;
1045    // FIXME: Cleanup.
1046    if (!ForVirtualBase) {
1047      // then virtual base offsets...
1048      for (std::vector<llvm::Constant *>::reverse_iterator i = offsets.rbegin(),
1049             e = offsets.rend(); i != e; ++i)
1050        methods.push_back(*i);
1051    }
1052
1053    // The vcalls come first...
1054    for (std::vector<Index_t>::iterator i=VCalls.begin(), e=VCalls.end();
1055         i < e; ++i)
1056      methods.push_back(wrap((0?600:0) + *i));
1057    VCalls.clear();
1058
1059    if (ForVirtualBase) {
1060      // then virtual base offsets...
1061      for (std::vector<llvm::Constant *>::reverse_iterator i = offsets.rbegin(),
1062             e = offsets.rend(); i != e; ++i)
1063        methods.push_back(*i);
1064    }
1065
1066    methods.push_back(wrap(-(Offset/8)));
1067    methods.push_back(rtti);
1068    Index_t AddressPoint = methods.size();
1069
1070    methods.insert(methods.end(), submethods.begin(), submethods.end());
1071    submethods.clear();
1072    InstallThunks(AddressPoint);
1073
1074    // and then the non-virtual bases.
1075    NonVirtualBases(RD, Layout, PrimaryBase, PrimaryBaseWasVirtual,
1076                    MorallyVirtual, Offset);
1077    return AddressPoint;
1078  }
1079
1080  void Primaries(const CXXRecordDecl *RD, bool MorallyVirtual, int64_t Offset) {
1081    if (!RD->isDynamicClass())
1082      return;
1083
1084    const ASTRecordLayout &Layout = CGM.getContext().getASTRecordLayout(RD);
1085    const CXXRecordDecl *PrimaryBase = Layout.getPrimaryBase();
1086    const bool PrimaryBaseWasVirtual = Layout.getPrimaryBaseWasVirtual();
1087
1088    // vtables are composed from the chain of primaries.
1089    if (PrimaryBase) {
1090      if (PrimaryBaseWasVirtual)
1091        IndirectPrimary.insert(PrimaryBase);
1092      Primaries(PrimaryBase, PrimaryBaseWasVirtual|MorallyVirtual, Offset);
1093    }
1094
1095    // And add the virtuals for the class to the primary vtable.
1096    AddMethods(RD, MorallyVirtual, Offset);
1097  }
1098
1099  int64_t GenerateVtableForBase(const CXXRecordDecl *RD,
1100                                bool MorallyVirtual = false, int64_t Offset = 0,
1101                                bool ForVirtualBase = false,
1102                                const CXXRecordDecl *FinalD = 0) {
1103    if (!RD->isDynamicClass())
1104      return 0;
1105
1106    const ASTRecordLayout &Layout = CGM.getContext().getASTRecordLayout(RD);
1107    const CXXRecordDecl *PrimaryBase = Layout.getPrimaryBase();
1108    const bool PrimaryBaseWasVirtual = Layout.getPrimaryBaseWasVirtual();
1109
1110    std::vector<llvm::Constant *> offsets;
1111    extra = 0;
1112    GenerateVBaseOffsets(offsets, RD, Offset);
1113    if (ForVirtualBase)
1114      extra = offsets.size();
1115
1116    // vtables are composed from the chain of primaries.
1117    if (PrimaryBase) {
1118      if (PrimaryBaseWasVirtual)
1119        IndirectPrimary.insert(PrimaryBase);
1120      Primaries(PrimaryBase, PrimaryBaseWasVirtual|MorallyVirtual, Offset);
1121    }
1122
1123    // And add the virtuals for the class to the primary vtable.
1124    AddMethods(RD, MorallyVirtual, Offset);
1125
1126    return end(RD, offsets, Layout, PrimaryBase, PrimaryBaseWasVirtual,
1127               MorallyVirtual, Offset, ForVirtualBase);
1128  }
1129
1130  void GenerateVtableForVBases(const CXXRecordDecl *RD) {
1131    for (CXXRecordDecl::base_class_const_iterator i = RD->bases_begin(),
1132           e = RD->bases_end(); i != e; ++i) {
1133      const CXXRecordDecl *Base =
1134        cast<CXXRecordDecl>(i->getType()->getAs<RecordType>()->getDecl());
1135      if (i->isVirtual() && !IndirectPrimary.count(Base)) {
1136        // Mark it so we don't output it twice.
1137        IndirectPrimary.insert(Base);
1138        StartNewTable();
1139        int64_t BaseOffset = BLayout.getVBaseClassOffset(Base);
1140        Index_t AP;
1141        AP = GenerateVtableForBase(Base, true, BaseOffset, true, RD);
1142        OverrideMethods(RD, AP, true, BaseOffset);
1143        InstallThunks(AP);
1144      }
1145      if (Base->getNumVBases())
1146        GenerateVtableForVBases(Base);
1147    }
1148  }
1149};
1150
1151class VtableInfo {
1152public:
1153  typedef VtableBuilder::Index_t Index_t;
1154private:
1155  CodeGenModule &CGM;  // Per-module state.
1156  /// Index_t - Vtable index type.
1157  typedef llvm::DenseMap<const CXXMethodDecl *, Index_t> ElTy;
1158  typedef llvm::DenseMap<const CXXRecordDecl *, ElTy *> MapTy;
1159  // FIXME: Move to Context.
1160  static MapTy IndexFor;
1161public:
1162  VtableInfo(CodeGenModule &cgm) : CGM(cgm) { }
1163  void register_index(const CXXRecordDecl *RD, const ElTy &e) {
1164    assert(IndexFor.find(RD) == IndexFor.end() && "Don't compute vtbl twice");
1165    // We own a copy of this, it will go away shortly.
1166    new ElTy (e);
1167    IndexFor[RD] = new ElTy (e);
1168  }
1169  Index_t lookup(const CXXMethodDecl *MD) {
1170    const CXXRecordDecl *RD = MD->getParent();
1171    MapTy::iterator I = IndexFor.find(RD);
1172    if (I == IndexFor.end()) {
1173      std::vector<llvm::Constant *> methods;
1174      VtableBuilder b(methods, RD, CGM);
1175      b.GenerateVtableForBase(RD);
1176      b.GenerateVtableForVBases(RD);
1177      register_index(RD, b.getIndex());
1178      I = IndexFor.find(RD);
1179    }
1180    assert(I->second->find(MD)!=I->second->end() && "Can't find vtable index");
1181    return (*I->second)[MD];
1182  }
1183};
1184
1185// FIXME: Move to Context.
1186VtableInfo::MapTy VtableInfo::IndexFor;
1187
1188llvm::Value *CodeGenFunction::GenerateVtable(const CXXRecordDecl *RD) {
1189  llvm::SmallString<256> OutName;
1190  llvm::raw_svector_ostream Out(OutName);
1191  QualType ClassTy;
1192  ClassTy = getContext().getTagDeclType(RD);
1193  mangleCXXVtable(ClassTy, getContext(), Out);
1194  llvm::GlobalVariable::LinkageTypes linktype;
1195  linktype = llvm::GlobalValue::WeakAnyLinkage;
1196  std::vector<llvm::Constant *> methods;
1197  llvm::Type *Ptr8Ty=llvm::PointerType::get(llvm::Type::getInt8Ty(VMContext),0);
1198  int64_t Offset;
1199
1200  VtableBuilder b(methods, RD, CGM);
1201
1202  // First comes the vtables for all the non-virtual bases...
1203  Offset = b.GenerateVtableForBase(RD);
1204
1205  // then the vtables for all the virtual bases.
1206  b.GenerateVtableForVBases(RD);
1207
1208  llvm::Constant *C;
1209  llvm::ArrayType *type = llvm::ArrayType::get(Ptr8Ty, methods.size());
1210  C = llvm::ConstantArray::get(type, methods);
1211  llvm::Value *vtable = new llvm::GlobalVariable(CGM.getModule(), type, true,
1212                                                 linktype, C, Out.str());
1213  vtable = Builder.CreateBitCast(vtable, Ptr8Ty);
1214  vtable = Builder.CreateGEP(vtable,
1215                       llvm::ConstantInt::get(llvm::Type::getInt64Ty(VMContext),
1216                                              Offset*LLVMPointerWidth/8));
1217  return vtable;
1218}
1219
1220// FIXME: move to Context
1221static VtableInfo *vtableinfo;
1222
1223llvm::Constant *CodeGenFunction::GenerateThunk(llvm::Function *Fn,
1224                                               const CXXMethodDecl *MD,
1225                                               bool Extern, int64_t nv,
1226                                               int64_t v) {
1227  QualType R = MD->getType()->getAsFunctionType()->getResultType();
1228
1229  FunctionArgList Args;
1230  ImplicitParamDecl *ThisDecl =
1231    ImplicitParamDecl::Create(getContext(), 0, SourceLocation(), 0,
1232                              MD->getThisType(getContext()));
1233  Args.push_back(std::make_pair(ThisDecl, ThisDecl->getType()));
1234  for (FunctionDecl::param_const_iterator i = MD->param_begin(),
1235         e = MD->param_end();
1236       i != e; ++i) {
1237    ParmVarDecl *D = *i;
1238    Args.push_back(std::make_pair(D, D->getType()));
1239  }
1240  IdentifierInfo *II
1241    = &CGM.getContext().Idents.get("__thunk_named_foo_");
1242  FunctionDecl *FD = FunctionDecl::Create(getContext(),
1243                                          getContext().getTranslationUnitDecl(),
1244                                          SourceLocation(), II, R, 0,
1245                                          Extern
1246                                            ? FunctionDecl::Extern
1247                                            : FunctionDecl::Static,
1248                                          false, true);
1249  StartFunction(FD, R, Fn, Args, SourceLocation());
1250  // FIXME: generate body
1251  FinishFunction();
1252  return Fn;
1253}
1254
1255llvm::Constant *CodeGenModule::BuildThunk(const CXXMethodDecl *MD, bool Extern,
1256                                          int64_t nv, int64_t v) {
1257  llvm::SmallString<256> OutName;
1258  llvm::raw_svector_ostream Out(OutName);
1259  mangleThunk(MD, nv, v, getContext(), Out);
1260  llvm::GlobalVariable::LinkageTypes linktype;
1261  linktype = llvm::GlobalValue::WeakAnyLinkage;
1262  if (!Extern)
1263    linktype = llvm::GlobalValue::InternalLinkage;
1264  llvm::Type *Ptr8Ty=llvm::PointerType::get(llvm::Type::getInt8Ty(VMContext),0);
1265  const FunctionProtoType *FPT = MD->getType()->getAsFunctionProtoType();
1266  const llvm::FunctionType *FTy =
1267    getTypes().GetFunctionType(getTypes().getFunctionInfo(MD),
1268                               FPT->isVariadic());
1269
1270  llvm::Function *Fn = llvm::Function::Create(FTy, linktype, Out.str(),
1271                                              &getModule());
1272  CodeGenFunction(*this).GenerateThunk(Fn, MD, Extern, nv, v);
1273  // Fn = Builder.CreateBitCast(Fn, Ptr8Ty);
1274  llvm::Constant *m = llvm::ConstantExpr::getBitCast(Fn, Ptr8Ty);
1275  return m;
1276}
1277
1278llvm::Value *
1279CodeGenFunction::BuildVirtualCall(const CXXMethodDecl *MD, llvm::Value *&This,
1280                                  const llvm::Type *Ty) {
1281  // FIXME: If we know the dynamic type, we don't have to do a virtual dispatch.
1282
1283  // FIXME: move to Context
1284  if (vtableinfo == 0)
1285    vtableinfo = new VtableInfo(CGM);
1286
1287  VtableInfo::Index_t Idx = vtableinfo->lookup(MD);
1288
1289  Ty = llvm::PointerType::get(Ty, 0);
1290  Ty = llvm::PointerType::get(Ty, 0);
1291  Ty = llvm::PointerType::get(Ty, 0);
1292  llvm::Value *vtbl = Builder.CreateBitCast(This, Ty);
1293  vtbl = Builder.CreateLoad(vtbl);
1294  llvm::Value *vfn = Builder.CreateConstInBoundsGEP1_64(vtbl,
1295                                                        Idx, "vfn");
1296  vfn = Builder.CreateLoad(vfn);
1297  return vfn;
1298}
1299
1300/// EmitClassAggrMemberwiseCopy - This routine generates code to copy a class
1301/// array of objects from SrcValue to DestValue. Copying can be either a bitwise
1302/// copy or via a copy constructor call.
1303//  FIXME. Consolidate this with EmitCXXAggrConstructorCall.
1304void CodeGenFunction::EmitClassAggrMemberwiseCopy(llvm::Value *Dest,
1305                                            llvm::Value *Src,
1306                                            const ArrayType *Array,
1307                                            const CXXRecordDecl *BaseClassDecl,
1308                                            QualType Ty) {
1309  const ConstantArrayType *CA = dyn_cast<ConstantArrayType>(Array);
1310  assert(CA && "VLA cannot be copied over");
1311  bool BitwiseCopy = BaseClassDecl->hasTrivialCopyConstructor();
1312
1313  // Create a temporary for the loop index and initialize it with 0.
1314  llvm::Value *IndexPtr = CreateTempAlloca(llvm::Type::getInt64Ty(VMContext),
1315                                           "loop.index");
1316  llvm::Value* zeroConstant =
1317    llvm::Constant::getNullValue(llvm::Type::getInt64Ty(VMContext));
1318    Builder.CreateStore(zeroConstant, IndexPtr, false);
1319  // Start the loop with a block that tests the condition.
1320  llvm::BasicBlock *CondBlock = createBasicBlock("for.cond");
1321  llvm::BasicBlock *AfterFor = createBasicBlock("for.end");
1322
1323  EmitBlock(CondBlock);
1324
1325  llvm::BasicBlock *ForBody = createBasicBlock("for.body");
1326  // Generate: if (loop-index < number-of-elements fall to the loop body,
1327  // otherwise, go to the block after the for-loop.
1328  uint64_t NumElements = getContext().getConstantArrayElementCount(CA);
1329  llvm::Value * NumElementsPtr =
1330    llvm::ConstantInt::get(llvm::Type::getInt64Ty(VMContext), NumElements);
1331  llvm::Value *Counter = Builder.CreateLoad(IndexPtr);
1332  llvm::Value *IsLess = Builder.CreateICmpULT(Counter, NumElementsPtr,
1333                                              "isless");
1334  // If the condition is true, execute the body.
1335  Builder.CreateCondBr(IsLess, ForBody, AfterFor);
1336
1337  EmitBlock(ForBody);
1338  llvm::BasicBlock *ContinueBlock = createBasicBlock("for.inc");
1339  // Inside the loop body, emit the constructor call on the array element.
1340  Counter = Builder.CreateLoad(IndexPtr);
1341  Src = Builder.CreateInBoundsGEP(Src, Counter, "srcaddress");
1342  Dest = Builder.CreateInBoundsGEP(Dest, Counter, "destaddress");
1343  if (BitwiseCopy)
1344    EmitAggregateCopy(Dest, Src, Ty);
1345  else if (CXXConstructorDecl *BaseCopyCtor =
1346           BaseClassDecl->getCopyConstructor(getContext(), 0)) {
1347    llvm::Value *Callee = CGM.GetAddrOfCXXConstructor(BaseCopyCtor,
1348                                                      Ctor_Complete);
1349    CallArgList CallArgs;
1350    // Push the this (Dest) ptr.
1351    CallArgs.push_back(std::make_pair(RValue::get(Dest),
1352                                      BaseCopyCtor->getThisType(getContext())));
1353
1354    // Push the Src ptr.
1355    CallArgs.push_back(std::make_pair(RValue::get(Src),
1356                                      BaseCopyCtor->getParamDecl(0)->getType()));
1357    QualType ResultType =
1358      BaseCopyCtor->getType()->getAsFunctionType()->getResultType();
1359    EmitCall(CGM.getTypes().getFunctionInfo(ResultType, CallArgs),
1360             Callee, CallArgs, BaseCopyCtor);
1361  }
1362  EmitBlock(ContinueBlock);
1363
1364  // Emit the increment of the loop counter.
1365  llvm::Value *NextVal = llvm::ConstantInt::get(Counter->getType(), 1);
1366  Counter = Builder.CreateLoad(IndexPtr);
1367  NextVal = Builder.CreateAdd(Counter, NextVal, "inc");
1368  Builder.CreateStore(NextVal, IndexPtr, false);
1369
1370  // Finally, branch back up to the condition for the next iteration.
1371  EmitBranch(CondBlock);
1372
1373  // Emit the fall-through block.
1374  EmitBlock(AfterFor, true);
1375}
1376
1377/// EmitClassAggrCopyAssignment - This routine generates code to assign a class
1378/// array of objects from SrcValue to DestValue. Assignment can be either a
1379/// bitwise assignment or via a copy assignment operator function call.
1380/// FIXME. This can be consolidated with EmitClassAggrMemberwiseCopy
1381void CodeGenFunction::EmitClassAggrCopyAssignment(llvm::Value *Dest,
1382                                            llvm::Value *Src,
1383                                            const ArrayType *Array,
1384                                            const CXXRecordDecl *BaseClassDecl,
1385                                            QualType Ty) {
1386  const ConstantArrayType *CA = dyn_cast<ConstantArrayType>(Array);
1387  assert(CA && "VLA cannot be asssigned");
1388  bool BitwiseAssign = BaseClassDecl->hasTrivialCopyAssignment();
1389
1390  // Create a temporary for the loop index and initialize it with 0.
1391  llvm::Value *IndexPtr = CreateTempAlloca(llvm::Type::getInt64Ty(VMContext),
1392                                           "loop.index");
1393  llvm::Value* zeroConstant =
1394  llvm::Constant::getNullValue(llvm::Type::getInt64Ty(VMContext));
1395  Builder.CreateStore(zeroConstant, IndexPtr, false);
1396  // Start the loop with a block that tests the condition.
1397  llvm::BasicBlock *CondBlock = createBasicBlock("for.cond");
1398  llvm::BasicBlock *AfterFor = createBasicBlock("for.end");
1399
1400  EmitBlock(CondBlock);
1401
1402  llvm::BasicBlock *ForBody = createBasicBlock("for.body");
1403  // Generate: if (loop-index < number-of-elements fall to the loop body,
1404  // otherwise, go to the block after the for-loop.
1405  uint64_t NumElements = getContext().getConstantArrayElementCount(CA);
1406  llvm::Value * NumElementsPtr =
1407  llvm::ConstantInt::get(llvm::Type::getInt64Ty(VMContext), NumElements);
1408  llvm::Value *Counter = Builder.CreateLoad(IndexPtr);
1409  llvm::Value *IsLess = Builder.CreateICmpULT(Counter, NumElementsPtr,
1410                                              "isless");
1411  // If the condition is true, execute the body.
1412  Builder.CreateCondBr(IsLess, ForBody, AfterFor);
1413
1414  EmitBlock(ForBody);
1415  llvm::BasicBlock *ContinueBlock = createBasicBlock("for.inc");
1416  // Inside the loop body, emit the assignment operator call on array element.
1417  Counter = Builder.CreateLoad(IndexPtr);
1418  Src = Builder.CreateInBoundsGEP(Src, Counter, "srcaddress");
1419  Dest = Builder.CreateInBoundsGEP(Dest, Counter, "destaddress");
1420  const CXXMethodDecl *MD = 0;
1421  if (BitwiseAssign)
1422    EmitAggregateCopy(Dest, Src, Ty);
1423  else {
1424    bool hasCopyAssign = BaseClassDecl->hasConstCopyAssignment(getContext(),
1425                                                               MD);
1426    assert(hasCopyAssign && "EmitClassAggrCopyAssignment - No user assign");
1427    (void)hasCopyAssign;
1428    const FunctionProtoType *FPT = MD->getType()->getAsFunctionProtoType();
1429    const llvm::Type *LTy =
1430    CGM.getTypes().GetFunctionType(CGM.getTypes().getFunctionInfo(MD),
1431                                   FPT->isVariadic());
1432    llvm::Constant *Callee = CGM.GetAddrOfFunction(GlobalDecl(MD), LTy);
1433
1434    CallArgList CallArgs;
1435    // Push the this (Dest) ptr.
1436    CallArgs.push_back(std::make_pair(RValue::get(Dest),
1437                                      MD->getThisType(getContext())));
1438
1439    // Push the Src ptr.
1440    CallArgs.push_back(std::make_pair(RValue::get(Src),
1441                                      MD->getParamDecl(0)->getType()));
1442    QualType ResultType = MD->getType()->getAsFunctionType()->getResultType();
1443    EmitCall(CGM.getTypes().getFunctionInfo(ResultType, CallArgs),
1444             Callee, CallArgs, MD);
1445  }
1446  EmitBlock(ContinueBlock);
1447
1448  // Emit the increment of the loop counter.
1449  llvm::Value *NextVal = llvm::ConstantInt::get(Counter->getType(), 1);
1450  Counter = Builder.CreateLoad(IndexPtr);
1451  NextVal = Builder.CreateAdd(Counter, NextVal, "inc");
1452  Builder.CreateStore(NextVal, IndexPtr, false);
1453
1454  // Finally, branch back up to the condition for the next iteration.
1455  EmitBranch(CondBlock);
1456
1457  // Emit the fall-through block.
1458  EmitBlock(AfterFor, true);
1459}
1460
1461/// EmitClassMemberwiseCopy - This routine generates code to copy a class
1462/// object from SrcValue to DestValue. Copying can be either a bitwise copy
1463/// or via a copy constructor call.
1464void CodeGenFunction::EmitClassMemberwiseCopy(
1465                        llvm::Value *Dest, llvm::Value *Src,
1466                        const CXXRecordDecl *ClassDecl,
1467                        const CXXRecordDecl *BaseClassDecl, QualType Ty) {
1468  if (ClassDecl) {
1469    Dest = AddressCXXOfBaseClass(Dest, ClassDecl, BaseClassDecl);
1470    Src = AddressCXXOfBaseClass(Src, ClassDecl, BaseClassDecl) ;
1471  }
1472  if (BaseClassDecl->hasTrivialCopyConstructor()) {
1473    EmitAggregateCopy(Dest, Src, Ty);
1474    return;
1475  }
1476
1477  if (CXXConstructorDecl *BaseCopyCtor =
1478      BaseClassDecl->getCopyConstructor(getContext(), 0)) {
1479    llvm::Value *Callee = CGM.GetAddrOfCXXConstructor(BaseCopyCtor,
1480                                                      Ctor_Complete);
1481    CallArgList CallArgs;
1482    // Push the this (Dest) ptr.
1483    CallArgs.push_back(std::make_pair(RValue::get(Dest),
1484                                      BaseCopyCtor->getThisType(getContext())));
1485
1486    // Push the Src ptr.
1487    CallArgs.push_back(std::make_pair(RValue::get(Src),
1488                       BaseCopyCtor->getParamDecl(0)->getType()));
1489    QualType ResultType =
1490    BaseCopyCtor->getType()->getAsFunctionType()->getResultType();
1491    EmitCall(CGM.getTypes().getFunctionInfo(ResultType, CallArgs),
1492             Callee, CallArgs, BaseCopyCtor);
1493  }
1494}
1495
1496/// EmitClassCopyAssignment - This routine generates code to copy assign a class
1497/// object from SrcValue to DestValue. Assignment can be either a bitwise
1498/// assignment of via an assignment operator call.
1499// FIXME. Consolidate this with EmitClassMemberwiseCopy as they share a lot.
1500void CodeGenFunction::EmitClassCopyAssignment(
1501                                        llvm::Value *Dest, llvm::Value *Src,
1502                                        const CXXRecordDecl *ClassDecl,
1503                                        const CXXRecordDecl *BaseClassDecl,
1504                                        QualType Ty) {
1505  if (ClassDecl) {
1506    Dest = AddressCXXOfBaseClass(Dest, ClassDecl, BaseClassDecl);
1507    Src = AddressCXXOfBaseClass(Src, ClassDecl, BaseClassDecl) ;
1508  }
1509  if (BaseClassDecl->hasTrivialCopyAssignment()) {
1510    EmitAggregateCopy(Dest, Src, Ty);
1511    return;
1512  }
1513
1514  const CXXMethodDecl *MD = 0;
1515  bool ConstCopyAssignOp = BaseClassDecl->hasConstCopyAssignment(getContext(),
1516                                                                 MD);
1517  assert(ConstCopyAssignOp && "EmitClassCopyAssignment - missing copy assign");
1518  (void)ConstCopyAssignOp;
1519
1520  const FunctionProtoType *FPT = MD->getType()->getAsFunctionProtoType();
1521  const llvm::Type *LTy =
1522    CGM.getTypes().GetFunctionType(CGM.getTypes().getFunctionInfo(MD),
1523                                   FPT->isVariadic());
1524  llvm::Constant *Callee = CGM.GetAddrOfFunction(GlobalDecl(MD), LTy);
1525
1526  CallArgList CallArgs;
1527  // Push the this (Dest) ptr.
1528  CallArgs.push_back(std::make_pair(RValue::get(Dest),
1529                                    MD->getThisType(getContext())));
1530
1531  // Push the Src ptr.
1532  CallArgs.push_back(std::make_pair(RValue::get(Src),
1533                                    MD->getParamDecl(0)->getType()));
1534  QualType ResultType =
1535    MD->getType()->getAsFunctionType()->getResultType();
1536  EmitCall(CGM.getTypes().getFunctionInfo(ResultType, CallArgs),
1537           Callee, CallArgs, MD);
1538}
1539
1540/// SynthesizeDefaultConstructor - synthesize a default constructor
1541void
1542CodeGenFunction::SynthesizeDefaultConstructor(const CXXConstructorDecl *CD,
1543                                              const FunctionDecl *FD,
1544                                              llvm::Function *Fn,
1545                                              const FunctionArgList &Args) {
1546  StartFunction(FD, FD->getResultType(), Fn, Args, SourceLocation());
1547  EmitCtorPrologue(CD);
1548  FinishFunction();
1549}
1550
1551/// SynthesizeCXXCopyConstructor - This routine implicitly defines body of a copy
1552/// constructor, in accordance with section 12.8 (p7 and p8) of C++03
1553/// The implicitly-defined copy constructor for class X performs a memberwise
1554/// copy of its subobjects. The order of copying is the same as the order
1555/// of initialization of bases and members in a user-defined constructor
1556/// Each subobject is copied in the manner appropriate to its type:
1557///  if the subobject is of class type, the copy constructor for the class is
1558///  used;
1559///  if the subobject is an array, each element is copied, in the manner
1560///  appropriate to the element type;
1561///  if the subobject is of scalar type, the built-in assignment operator is
1562///  used.
1563/// Virtual base class subobjects shall be copied only once by the
1564/// implicitly-defined copy constructor
1565
1566void CodeGenFunction::SynthesizeCXXCopyConstructor(const CXXConstructorDecl *CD,
1567                                       const FunctionDecl *FD,
1568                                       llvm::Function *Fn,
1569                                       const FunctionArgList &Args) {
1570  const CXXRecordDecl *ClassDecl = cast<CXXRecordDecl>(CD->getDeclContext());
1571  assert(!ClassDecl->hasUserDeclaredCopyConstructor() &&
1572         "SynthesizeCXXCopyConstructor - copy constructor has definition already");
1573  StartFunction(FD, FD->getResultType(), Fn, Args, SourceLocation());
1574
1575  FunctionArgList::const_iterator i = Args.begin();
1576  const VarDecl *ThisArg = i->first;
1577  llvm::Value *ThisObj = GetAddrOfLocalVar(ThisArg);
1578  llvm::Value *LoadOfThis = Builder.CreateLoad(ThisObj, "this");
1579  const VarDecl *SrcArg = (i+1)->first;
1580  llvm::Value *SrcObj = GetAddrOfLocalVar(SrcArg);
1581  llvm::Value *LoadOfSrc = Builder.CreateLoad(SrcObj);
1582
1583  for (CXXRecordDecl::base_class_const_iterator Base = ClassDecl->bases_begin();
1584       Base != ClassDecl->bases_end(); ++Base) {
1585    // FIXME. copy constrution of virtual base NYI
1586    if (Base->isVirtual())
1587      continue;
1588
1589    CXXRecordDecl *BaseClassDecl
1590      = cast<CXXRecordDecl>(Base->getType()->getAs<RecordType>()->getDecl());
1591    EmitClassMemberwiseCopy(LoadOfThis, LoadOfSrc, ClassDecl, BaseClassDecl,
1592                            Base->getType());
1593  }
1594
1595  for (CXXRecordDecl::field_iterator Field = ClassDecl->field_begin(),
1596       FieldEnd = ClassDecl->field_end();
1597       Field != FieldEnd; ++Field) {
1598    QualType FieldType = getContext().getCanonicalType((*Field)->getType());
1599    const ConstantArrayType *Array =
1600      getContext().getAsConstantArrayType(FieldType);
1601    if (Array)
1602      FieldType = getContext().getBaseElementType(FieldType);
1603
1604    if (const RecordType *FieldClassType = FieldType->getAs<RecordType>()) {
1605      CXXRecordDecl *FieldClassDecl
1606        = cast<CXXRecordDecl>(FieldClassType->getDecl());
1607      LValue LHS = EmitLValueForField(LoadOfThis, *Field, false, 0);
1608      LValue RHS = EmitLValueForField(LoadOfSrc, *Field, false, 0);
1609      if (Array) {
1610        const llvm::Type *BasePtr = ConvertType(FieldType);
1611        BasePtr = llvm::PointerType::getUnqual(BasePtr);
1612        llvm::Value *DestBaseAddrPtr =
1613          Builder.CreateBitCast(LHS.getAddress(), BasePtr);
1614        llvm::Value *SrcBaseAddrPtr =
1615          Builder.CreateBitCast(RHS.getAddress(), BasePtr);
1616        EmitClassAggrMemberwiseCopy(DestBaseAddrPtr, SrcBaseAddrPtr, Array,
1617                                    FieldClassDecl, FieldType);
1618      }
1619      else
1620        EmitClassMemberwiseCopy(LHS.getAddress(), RHS.getAddress(),
1621                                0 /*ClassDecl*/, FieldClassDecl, FieldType);
1622      continue;
1623    }
1624    // Do a built-in assignment of scalar data members.
1625    LValue LHS = EmitLValueForField(LoadOfThis, *Field, false, 0);
1626    LValue RHS = EmitLValueForField(LoadOfSrc, *Field, false, 0);
1627    RValue RVRHS = EmitLoadOfLValue(RHS, FieldType);
1628    EmitStoreThroughLValue(RVRHS, LHS, FieldType);
1629  }
1630  FinishFunction();
1631}
1632
1633/// SynthesizeCXXCopyAssignment - Implicitly define copy assignment operator.
1634/// Before the implicitly-declared copy assignment operator for a class is
1635/// implicitly defined, all implicitly- declared copy assignment operators for
1636/// its direct base classes and its nonstatic data members shall have been
1637/// implicitly defined. [12.8-p12]
1638/// The implicitly-defined copy assignment operator for class X performs
1639/// memberwise assignment of its subob- jects. The direct base classes of X are
1640/// assigned first, in the order of their declaration in
1641/// the base-specifier-list, and then the immediate nonstatic data members of X
1642/// are assigned, in the order in which they were declared in the class
1643/// definition.Each subobject is assigned in the manner appropriate to its type:
1644///   if the subobject is of class type, the copy assignment operator for the
1645///   class is used (as if by explicit qualification; that is, ignoring any
1646///   possible virtual overriding functions in more derived classes);
1647///
1648///   if the subobject is an array, each element is assigned, in the manner
1649///   appropriate to the element type;
1650///
1651///   if the subobject is of scalar type, the built-in assignment operator is
1652///   used.
1653void CodeGenFunction::SynthesizeCXXCopyAssignment(const CXXMethodDecl *CD,
1654                                                  const FunctionDecl *FD,
1655                                                  llvm::Function *Fn,
1656                                                  const FunctionArgList &Args) {
1657
1658  const CXXRecordDecl *ClassDecl = cast<CXXRecordDecl>(CD->getDeclContext());
1659  assert(!ClassDecl->hasUserDeclaredCopyAssignment() &&
1660         "SynthesizeCXXCopyAssignment - copy assignment has user declaration");
1661  StartFunction(FD, FD->getResultType(), Fn, Args, SourceLocation());
1662
1663  FunctionArgList::const_iterator i = Args.begin();
1664  const VarDecl *ThisArg = i->first;
1665  llvm::Value *ThisObj = GetAddrOfLocalVar(ThisArg);
1666  llvm::Value *LoadOfThis = Builder.CreateLoad(ThisObj, "this");
1667  const VarDecl *SrcArg = (i+1)->first;
1668  llvm::Value *SrcObj = GetAddrOfLocalVar(SrcArg);
1669  llvm::Value *LoadOfSrc = Builder.CreateLoad(SrcObj);
1670
1671  for (CXXRecordDecl::base_class_const_iterator Base = ClassDecl->bases_begin();
1672       Base != ClassDecl->bases_end(); ++Base) {
1673    // FIXME. copy assignment of virtual base NYI
1674    if (Base->isVirtual())
1675      continue;
1676
1677    CXXRecordDecl *BaseClassDecl
1678      = cast<CXXRecordDecl>(Base->getType()->getAs<RecordType>()->getDecl());
1679    EmitClassCopyAssignment(LoadOfThis, LoadOfSrc, ClassDecl, BaseClassDecl,
1680                            Base->getType());
1681  }
1682
1683  for (CXXRecordDecl::field_iterator Field = ClassDecl->field_begin(),
1684       FieldEnd = ClassDecl->field_end();
1685       Field != FieldEnd; ++Field) {
1686    QualType FieldType = getContext().getCanonicalType((*Field)->getType());
1687    const ConstantArrayType *Array =
1688      getContext().getAsConstantArrayType(FieldType);
1689    if (Array)
1690      FieldType = getContext().getBaseElementType(FieldType);
1691
1692    if (const RecordType *FieldClassType = FieldType->getAs<RecordType>()) {
1693      CXXRecordDecl *FieldClassDecl
1694      = cast<CXXRecordDecl>(FieldClassType->getDecl());
1695      LValue LHS = EmitLValueForField(LoadOfThis, *Field, false, 0);
1696      LValue RHS = EmitLValueForField(LoadOfSrc, *Field, false, 0);
1697      if (Array) {
1698        const llvm::Type *BasePtr = ConvertType(FieldType);
1699        BasePtr = llvm::PointerType::getUnqual(BasePtr);
1700        llvm::Value *DestBaseAddrPtr =
1701          Builder.CreateBitCast(LHS.getAddress(), BasePtr);
1702        llvm::Value *SrcBaseAddrPtr =
1703          Builder.CreateBitCast(RHS.getAddress(), BasePtr);
1704        EmitClassAggrCopyAssignment(DestBaseAddrPtr, SrcBaseAddrPtr, Array,
1705                                    FieldClassDecl, FieldType);
1706      }
1707      else
1708        EmitClassCopyAssignment(LHS.getAddress(), RHS.getAddress(),
1709                               0 /*ClassDecl*/, FieldClassDecl, FieldType);
1710      continue;
1711    }
1712    // Do a built-in assignment of scalar data members.
1713    LValue LHS = EmitLValueForField(LoadOfThis, *Field, false, 0);
1714    LValue RHS = EmitLValueForField(LoadOfSrc, *Field, false, 0);
1715    RValue RVRHS = EmitLoadOfLValue(RHS, FieldType);
1716    EmitStoreThroughLValue(RVRHS, LHS, FieldType);
1717  }
1718
1719  // return *this;
1720  Builder.CreateStore(LoadOfThis, ReturnValue);
1721
1722  FinishFunction();
1723}
1724
1725/// EmitCtorPrologue - This routine generates necessary code to initialize
1726/// base classes and non-static data members belonging to this constructor.
1727/// FIXME: This needs to take a CXXCtorType.
1728void CodeGenFunction::EmitCtorPrologue(const CXXConstructorDecl *CD) {
1729  const CXXRecordDecl *ClassDecl = cast<CXXRecordDecl>(CD->getDeclContext());
1730  // FIXME: Add vbase initialization
1731  llvm::Value *LoadOfThis = 0;
1732
1733  for (CXXConstructorDecl::init_const_iterator B = CD->init_begin(),
1734       E = CD->init_end();
1735       B != E; ++B) {
1736    CXXBaseOrMemberInitializer *Member = (*B);
1737    if (Member->isBaseInitializer()) {
1738      LoadOfThis = LoadCXXThis();
1739      Type *BaseType = Member->getBaseClass();
1740      CXXRecordDecl *BaseClassDecl =
1741        cast<CXXRecordDecl>(BaseType->getAs<RecordType>()->getDecl());
1742      llvm::Value *V = AddressCXXOfBaseClass(LoadOfThis, ClassDecl,
1743                                             BaseClassDecl);
1744      EmitCXXConstructorCall(Member->getConstructor(),
1745                             Ctor_Complete, V,
1746                             Member->const_arg_begin(),
1747                             Member->const_arg_end());
1748    } else {
1749      // non-static data member initilaizers.
1750      FieldDecl *Field = Member->getMember();
1751      QualType FieldType = getContext().getCanonicalType((Field)->getType());
1752      const ConstantArrayType *Array =
1753        getContext().getAsConstantArrayType(FieldType);
1754      if (Array)
1755        FieldType = getContext().getBaseElementType(FieldType);
1756
1757      LoadOfThis = LoadCXXThis();
1758      LValue LHS;
1759      if (FieldType->isReferenceType()) {
1760        // FIXME: This is really ugly; should be refactored somehow
1761        unsigned idx = CGM.getTypes().getLLVMFieldNo(Field);
1762        llvm::Value *V = Builder.CreateStructGEP(LoadOfThis, idx, "tmp");
1763        LHS = LValue::MakeAddr(V, FieldType.getCVRQualifiers(),
1764                               QualType::GCNone, FieldType.getAddressSpace());
1765      } else {
1766        LHS = EmitLValueForField(LoadOfThis, Field, false, 0);
1767      }
1768      if (FieldType->getAs<RecordType>()) {
1769        if (!Field->isAnonymousStructOrUnion()) {
1770          assert(Member->getConstructor() &&
1771                 "EmitCtorPrologue - no constructor to initialize member");
1772          if (Array) {
1773            const llvm::Type *BasePtr = ConvertType(FieldType);
1774            BasePtr = llvm::PointerType::getUnqual(BasePtr);
1775            llvm::Value *BaseAddrPtr =
1776            Builder.CreateBitCast(LHS.getAddress(), BasePtr);
1777            EmitCXXAggrConstructorCall(Member->getConstructor(),
1778                                       Array, BaseAddrPtr);
1779          }
1780          else
1781            EmitCXXConstructorCall(Member->getConstructor(),
1782                                   Ctor_Complete, LHS.getAddress(),
1783                                   Member->const_arg_begin(),
1784                                   Member->const_arg_end());
1785          continue;
1786        }
1787        else {
1788          // Initializing an anonymous union data member.
1789          FieldDecl *anonMember = Member->getAnonUnionMember();
1790          LHS = EmitLValueForField(LHS.getAddress(), anonMember,
1791                                   /*IsUnion=*/true, 0);
1792          FieldType = anonMember->getType();
1793        }
1794      }
1795
1796      assert(Member->getNumArgs() == 1 && "Initializer count must be 1 only");
1797      Expr *RhsExpr = *Member->arg_begin();
1798      RValue RHS;
1799      if (FieldType->isReferenceType())
1800        RHS = EmitReferenceBindingToExpr(RhsExpr, FieldType,
1801                                        /*IsInitializer=*/true);
1802      else
1803        RHS = RValue::get(EmitScalarExpr(RhsExpr, true));
1804      EmitStoreThroughLValue(RHS, LHS, FieldType);
1805    }
1806  }
1807
1808  if (!CD->getNumBaseOrMemberInitializers() && !CD->isTrivial()) {
1809    // Nontrivial default constructor with no initializer list. It may still
1810    // have bases classes and/or contain non-static data members which require
1811    // construction.
1812    for (CXXRecordDecl::base_class_const_iterator Base =
1813          ClassDecl->bases_begin();
1814          Base != ClassDecl->bases_end(); ++Base) {
1815      // FIXME. copy assignment of virtual base NYI
1816      if (Base->isVirtual())
1817        continue;
1818
1819      CXXRecordDecl *BaseClassDecl
1820        = cast<CXXRecordDecl>(Base->getType()->getAs<RecordType>()->getDecl());
1821      if (BaseClassDecl->hasTrivialConstructor())
1822        continue;
1823      if (CXXConstructorDecl *BaseCX =
1824            BaseClassDecl->getDefaultConstructor(getContext())) {
1825        LoadOfThis = LoadCXXThis();
1826        llvm::Value *V = AddressCXXOfBaseClass(LoadOfThis, ClassDecl,
1827                                               BaseClassDecl);
1828        EmitCXXConstructorCall(BaseCX, Ctor_Complete, V, 0, 0);
1829      }
1830    }
1831
1832    for (CXXRecordDecl::field_iterator Field = ClassDecl->field_begin(),
1833         FieldEnd = ClassDecl->field_end();
1834         Field != FieldEnd; ++Field) {
1835      QualType FieldType = getContext().getCanonicalType((*Field)->getType());
1836      const ConstantArrayType *Array =
1837        getContext().getAsConstantArrayType(FieldType);
1838      if (Array)
1839        FieldType = getContext().getBaseElementType(FieldType);
1840      if (!FieldType->getAs<RecordType>() || Field->isAnonymousStructOrUnion())
1841        continue;
1842      const RecordType *ClassRec = FieldType->getAs<RecordType>();
1843      CXXRecordDecl *MemberClassDecl =
1844        dyn_cast<CXXRecordDecl>(ClassRec->getDecl());
1845      if (!MemberClassDecl || MemberClassDecl->hasTrivialConstructor())
1846        continue;
1847      if (CXXConstructorDecl *MamberCX =
1848            MemberClassDecl->getDefaultConstructor(getContext())) {
1849        LoadOfThis = LoadCXXThis();
1850        LValue LHS = EmitLValueForField(LoadOfThis, *Field, false, 0);
1851        if (Array) {
1852          const llvm::Type *BasePtr = ConvertType(FieldType);
1853          BasePtr = llvm::PointerType::getUnqual(BasePtr);
1854          llvm::Value *BaseAddrPtr =
1855            Builder.CreateBitCast(LHS.getAddress(), BasePtr);
1856          EmitCXXAggrConstructorCall(MamberCX, Array, BaseAddrPtr);
1857        }
1858        else
1859          EmitCXXConstructorCall(MamberCX, Ctor_Complete, LHS.getAddress(),
1860                                 0, 0);
1861      }
1862    }
1863  }
1864
1865  // Initialize the vtable pointer
1866  if (ClassDecl->isDynamicClass()) {
1867    if (!LoadOfThis)
1868      LoadOfThis = LoadCXXThis();
1869    llvm::Value *VtableField;
1870    llvm::Type *Ptr8Ty, *PtrPtr8Ty;
1871    Ptr8Ty = llvm::PointerType::get(llvm::Type::getInt8Ty(VMContext), 0);
1872    PtrPtr8Ty = llvm::PointerType::get(Ptr8Ty, 0);
1873    VtableField = Builder.CreateBitCast(LoadOfThis, PtrPtr8Ty);
1874    llvm::Value *vtable = GenerateVtable(ClassDecl);
1875    Builder.CreateStore(vtable, VtableField);
1876  }
1877}
1878
1879/// EmitDtorEpilogue - Emit all code that comes at the end of class's
1880/// destructor. This is to call destructors on members and base classes
1881/// in reverse order of their construction.
1882/// FIXME: This needs to take a CXXDtorType.
1883void CodeGenFunction::EmitDtorEpilogue(const CXXDestructorDecl *DD) {
1884  const CXXRecordDecl *ClassDecl = cast<CXXRecordDecl>(DD->getDeclContext());
1885  assert(!ClassDecl->getNumVBases() &&
1886         "FIXME: Destruction of virtual bases not supported");
1887  (void)ClassDecl;  // prevent warning.
1888
1889  for (CXXDestructorDecl::destr_const_iterator *B = DD->destr_begin(),
1890       *E = DD->destr_end(); B != E; ++B) {
1891    uintptr_t BaseOrMember = (*B);
1892    if (DD->isMemberToDestroy(BaseOrMember)) {
1893      FieldDecl *FD = DD->getMemberToDestroy(BaseOrMember);
1894      QualType FieldType = getContext().getCanonicalType((FD)->getType());
1895      const ConstantArrayType *Array =
1896        getContext().getAsConstantArrayType(FieldType);
1897      if (Array)
1898        FieldType = getContext().getBaseElementType(FieldType);
1899      const RecordType *RT = FieldType->getAs<RecordType>();
1900      CXXRecordDecl *FieldClassDecl = cast<CXXRecordDecl>(RT->getDecl());
1901      if (FieldClassDecl->hasTrivialDestructor())
1902        continue;
1903      llvm::Value *LoadOfThis = LoadCXXThis();
1904      LValue LHS = EmitLValueForField(LoadOfThis, FD, false, 0);
1905      if (Array) {
1906        const llvm::Type *BasePtr = ConvertType(FieldType);
1907        BasePtr = llvm::PointerType::getUnqual(BasePtr);
1908        llvm::Value *BaseAddrPtr =
1909          Builder.CreateBitCast(LHS.getAddress(), BasePtr);
1910        EmitCXXAggrDestructorCall(FieldClassDecl->getDestructor(getContext()),
1911                                  Array, BaseAddrPtr);
1912      }
1913      else
1914        EmitCXXDestructorCall(FieldClassDecl->getDestructor(getContext()),
1915                              Dtor_Complete, LHS.getAddress());
1916    } else {
1917      const RecordType *RT =
1918        DD->getAnyBaseClassToDestroy(BaseOrMember)->getAs<RecordType>();
1919      CXXRecordDecl *BaseClassDecl = cast<CXXRecordDecl>(RT->getDecl());
1920      if (BaseClassDecl->hasTrivialDestructor())
1921        continue;
1922      llvm::Value *V = AddressCXXOfBaseClass(LoadCXXThis(),
1923                                             ClassDecl,BaseClassDecl);
1924      EmitCXXDestructorCall(BaseClassDecl->getDestructor(getContext()),
1925                            Dtor_Complete, V);
1926    }
1927  }
1928  if (DD->getNumBaseOrMemberDestructions() || DD->isTrivial())
1929    return;
1930  // Case of destructor synthesis with fields and base classes
1931  // which have non-trivial destructors. They must be destructed in
1932  // reverse order of their construction.
1933  llvm::SmallVector<FieldDecl *, 16> DestructedFields;
1934
1935  for (CXXRecordDecl::field_iterator Field = ClassDecl->field_begin(),
1936       FieldEnd = ClassDecl->field_end();
1937       Field != FieldEnd; ++Field) {
1938    QualType FieldType = getContext().getCanonicalType((*Field)->getType());
1939    if (getContext().getAsConstantArrayType(FieldType))
1940      FieldType = getContext().getBaseElementType(FieldType);
1941    if (const RecordType *RT = FieldType->getAs<RecordType>()) {
1942      CXXRecordDecl *FieldClassDecl = cast<CXXRecordDecl>(RT->getDecl());
1943      if (FieldClassDecl->hasTrivialDestructor())
1944        continue;
1945      DestructedFields.push_back(*Field);
1946    }
1947  }
1948  if (!DestructedFields.empty())
1949    for (int i = DestructedFields.size() -1; i >= 0; --i) {
1950      FieldDecl *Field = DestructedFields[i];
1951      QualType FieldType = Field->getType();
1952      const ConstantArrayType *Array =
1953        getContext().getAsConstantArrayType(FieldType);
1954        if (Array)
1955          FieldType = getContext().getBaseElementType(FieldType);
1956      const RecordType *RT = FieldType->getAs<RecordType>();
1957      CXXRecordDecl *FieldClassDecl = cast<CXXRecordDecl>(RT->getDecl());
1958      llvm::Value *LoadOfThis = LoadCXXThis();
1959      LValue LHS = EmitLValueForField(LoadOfThis, Field, false, 0);
1960      if (Array) {
1961        const llvm::Type *BasePtr = ConvertType(FieldType);
1962        BasePtr = llvm::PointerType::getUnqual(BasePtr);
1963        llvm::Value *BaseAddrPtr =
1964        Builder.CreateBitCast(LHS.getAddress(), BasePtr);
1965        EmitCXXAggrDestructorCall(FieldClassDecl->getDestructor(getContext()),
1966                                  Array, BaseAddrPtr);
1967      }
1968      else
1969        EmitCXXDestructorCall(FieldClassDecl->getDestructor(getContext()),
1970                              Dtor_Complete, LHS.getAddress());
1971    }
1972
1973  llvm::SmallVector<CXXRecordDecl*, 4> DestructedBases;
1974  for (CXXRecordDecl::base_class_const_iterator Base = ClassDecl->bases_begin();
1975       Base != ClassDecl->bases_end(); ++Base) {
1976    // FIXME. copy assignment of virtual base NYI
1977    if (Base->isVirtual())
1978      continue;
1979
1980    CXXRecordDecl *BaseClassDecl
1981      = cast<CXXRecordDecl>(Base->getType()->getAs<RecordType>()->getDecl());
1982    if (BaseClassDecl->hasTrivialDestructor())
1983      continue;
1984    DestructedBases.push_back(BaseClassDecl);
1985  }
1986  if (DestructedBases.empty())
1987    return;
1988  for (int i = DestructedBases.size() -1; i >= 0; --i) {
1989    CXXRecordDecl *BaseClassDecl = DestructedBases[i];
1990    llvm::Value *V = AddressCXXOfBaseClass(LoadCXXThis(),
1991                                           ClassDecl,BaseClassDecl);
1992    EmitCXXDestructorCall(BaseClassDecl->getDestructor(getContext()),
1993                          Dtor_Complete, V);
1994  }
1995}
1996
1997void CodeGenFunction::SynthesizeDefaultDestructor(const CXXDestructorDecl *CD,
1998                                                  const FunctionDecl *FD,
1999                                                  llvm::Function *Fn,
2000                                                  const FunctionArgList &Args) {
2001
2002  const CXXRecordDecl *ClassDecl = cast<CXXRecordDecl>(CD->getDeclContext());
2003  assert(!ClassDecl->hasUserDeclaredDestructor() &&
2004         "SynthesizeDefaultDestructor - destructor has user declaration");
2005  (void) ClassDecl;
2006
2007  StartFunction(FD, FD->getResultType(), Fn, Args, SourceLocation());
2008  EmitDtorEpilogue(CD);
2009  FinishFunction();
2010}
2011