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Reid Spencer5f016e22007-07-11 17:01:13 +00001//===--- CGDecl.cpp - Emit LLVM Code for declarations ---------------------===//
2//
3// The LLVM Compiler Infrastructure
4//
Chris Lattner0bc735f2007-12-29 19:59:25 +00005// This file is distributed under the University of Illinois Open Source
6// License. See LICENSE.TXT for details.
Reid Spencer5f016e22007-07-11 17:01:13 +00007//
8//===----------------------------------------------------------------------===//
9//
10// This contains code to emit Decl nodes as LLVM code.
11//
12//===----------------------------------------------------------------------===//
13
Sanjiv Guptacc9b1632008-05-30 10:30:31 +000014#include "CGDebugInfo.h"
Reid Spencer5f016e22007-07-11 17:01:13 +000015#include "CodeGenFunction.h"
Anders Carlsson1a86b332007-10-17 00:52:43 +000016#include "CodeGenModule.h"
Daniel Dunbarde7fb842008-08-11 05:00:27 +000017#include "clang/AST/ASTContext.h"
Ken Dyckbdc601b2009-12-22 14:23:30 +000018#include "clang/AST/CharUnits.h"
Daniel Dunbarc4a1dea2008-08-11 05:35:13 +000019#include "clang/AST/Decl.h"
Anders Carlsson19567ee2008-08-25 01:38:19 +000020#include "clang/AST/DeclObjC.h"
Nate Begeman8bd4afe2008-04-19 04:17:09 +000021#include "clang/Basic/SourceManager.h"
Chris Lattner2621fd12008-05-08 05:58:21 +000022#include "clang/Basic/TargetInfo.h"
Chandler Carruth06057ce2010-06-15 23:19:56 +000023#include "clang/Frontend/CodeGenOptions.h"
Anders Carlsson1a86b332007-10-17 00:52:43 +000024#include "llvm/GlobalVariable.h"
Anders Carlsson5d463152008-12-12 07:38:43 +000025#include "llvm/Intrinsics.h"
Mike Stumpdab514f2009-03-04 03:23:46 +000026#include "llvm/Target/TargetData.h"
Reid Spencer5f016e22007-07-11 17:01:13 +000027#include "llvm/Type.h"
28using namespace clang;
29using namespace CodeGen;
30
31
32void CodeGenFunction::EmitDecl(const Decl &D) {
Reid Spencer5f016e22007-07-11 17:01:13 +000033 switch (D.getKind()) {
Douglas Gregor08688ac2010-04-23 02:02:43 +000034 case Decl::TranslationUnit:
35 case Decl::Namespace:
36 case Decl::UnresolvedUsingTypename:
37 case Decl::ClassTemplateSpecialization:
38 case Decl::ClassTemplatePartialSpecialization:
39 case Decl::TemplateTypeParm:
40 case Decl::UnresolvedUsingValue:
Sean Hunt9a555912010-05-30 07:21:58 +000041 case Decl::NonTypeTemplateParm:
Douglas Gregor08688ac2010-04-23 02:02:43 +000042 case Decl::CXXMethod:
43 case Decl::CXXConstructor:
44 case Decl::CXXDestructor:
45 case Decl::CXXConversion:
46 case Decl::Field:
Francois Pichet41f5e662010-11-21 06:49:41 +000047 case Decl::IndirectField:
Douglas Gregor08688ac2010-04-23 02:02:43 +000048 case Decl::ObjCIvar:
49 case Decl::ObjCAtDefsField:
Chris Lattneraa9fc462007-10-08 21:37:32 +000050 case Decl::ParmVar:
Douglas Gregor08688ac2010-04-23 02:02:43 +000051 case Decl::ImplicitParam:
52 case Decl::ClassTemplate:
53 case Decl::FunctionTemplate:
Richard Smith3e4c6c42011-05-05 21:57:07 +000054 case Decl::TypeAliasTemplate:
Douglas Gregor08688ac2010-04-23 02:02:43 +000055 case Decl::TemplateTemplateParm:
56 case Decl::ObjCMethod:
57 case Decl::ObjCCategory:
58 case Decl::ObjCProtocol:
59 case Decl::ObjCInterface:
60 case Decl::ObjCCategoryImpl:
61 case Decl::ObjCImplementation:
62 case Decl::ObjCProperty:
63 case Decl::ObjCCompatibleAlias:
Abramo Bagnara6206d532010-06-05 05:09:32 +000064 case Decl::AccessSpec:
Douglas Gregor08688ac2010-04-23 02:02:43 +000065 case Decl::LinkageSpec:
66 case Decl::ObjCPropertyImpl:
67 case Decl::ObjCClass:
68 case Decl::ObjCForwardProtocol:
69 case Decl::FileScopeAsm:
70 case Decl::Friend:
71 case Decl::FriendTemplate:
72 case Decl::Block:
Devang Patel12e6d832011-04-05 20:28:21 +000073 assert(0 && "Declaration should not be in declstmts!");
Reid Spencer5f016e22007-07-11 17:01:13 +000074 case Decl::Function: // void X();
Argyrios Kyrtzidis35bc0822008-10-15 00:42:39 +000075 case Decl::Record: // struct/union/class X;
Reid Spencer5f016e22007-07-11 17:01:13 +000076 case Decl::Enum: // enum X;
Mike Stump1eb44332009-09-09 15:08:12 +000077 case Decl::EnumConstant: // enum ? { X = ? }
Argyrios Kyrtzidis35bc0822008-10-15 00:42:39 +000078 case Decl::CXXRecord: // struct/union/class X; [C++]
Daniel Dunbarfa133a12009-11-23 00:07:06 +000079 case Decl::Using: // using X; [C++]
80 case Decl::UsingShadow:
81 case Decl::UsingDirective: // using namespace X; [C++]
Douglas Gregor08688ac2010-04-23 02:02:43 +000082 case Decl::NamespaceAlias:
Anders Carlsson7b0ca3f2009-12-03 17:26:31 +000083 case Decl::StaticAssert: // static_assert(X, ""); [C++0x]
Chris Lattner4ae493c2011-02-18 02:08:43 +000084 case Decl::Label: // __label__ x;
Reid Spencer5f016e22007-07-11 17:01:13 +000085 // None of these decls require codegen support.
86 return;
Mike Stump1eb44332009-09-09 15:08:12 +000087
Daniel Dunbar662174c82008-08-29 17:28:43 +000088 case Decl::Var: {
89 const VarDecl &VD = cast<VarDecl>(D);
John McCallb6bbcc92010-10-15 04:57:14 +000090 assert(VD.isLocalVarDecl() &&
Daniel Dunbar662174c82008-08-29 17:28:43 +000091 "Should not see file-scope variables inside a function!");
John McCallb6bbcc92010-10-15 04:57:14 +000092 return EmitVarDecl(VD);
Reid Spencer5f016e22007-07-11 17:01:13 +000093 }
Mike Stump1eb44332009-09-09 15:08:12 +000094
Richard Smith162e1c12011-04-15 14:24:37 +000095 case Decl::Typedef: // typedef int X;
96 case Decl::TypeAlias: { // using X = int; [C++0x]
97 const TypedefNameDecl &TD = cast<TypedefNameDecl>(D);
Anders Carlssonfcdbb932008-12-20 21:51:53 +000098 QualType Ty = TD.getUnderlyingType();
Mike Stump1eb44332009-09-09 15:08:12 +000099
Anders Carlssonfcdbb932008-12-20 21:51:53 +0000100 if (Ty->isVariablyModifiedType())
101 EmitVLASize(Ty);
102 }
Daniel Dunbar662174c82008-08-29 17:28:43 +0000103 }
Reid Spencer5f016e22007-07-11 17:01:13 +0000104}
105
John McCallb6bbcc92010-10-15 04:57:14 +0000106/// EmitVarDecl - This method handles emission of any variable declaration
Reid Spencer5f016e22007-07-11 17:01:13 +0000107/// inside a function, including static vars etc.
John McCallb6bbcc92010-10-15 04:57:14 +0000108void CodeGenFunction::EmitVarDecl(const VarDecl &D) {
Reid Spencer5f016e22007-07-11 17:01:13 +0000109 switch (D.getStorageClass()) {
John McCalld931b082010-08-26 03:08:43 +0000110 case SC_None:
111 case SC_Auto:
112 case SC_Register:
John McCallb6bbcc92010-10-15 04:57:14 +0000113 return EmitAutoVarDecl(D);
John McCalld931b082010-08-26 03:08:43 +0000114 case SC_Static: {
Anders Carlssonf6b89a12010-02-07 02:03:08 +0000115 llvm::GlobalValue::LinkageTypes Linkage =
116 llvm::GlobalValue::InternalLinkage;
117
John McCall8b242332010-05-25 04:30:21 +0000118 // If the function definition has some sort of weak linkage, its
119 // static variables should also be weak so that they get properly
120 // uniqued. We can't do this in C, though, because there's no
121 // standard way to agree on which variables are the same (i.e.
122 // there's no mangling).
123 if (getContext().getLangOptions().CPlusPlus)
124 if (llvm::GlobalValue::isWeakForLinker(CurFn->getLinkage()))
125 Linkage = CurFn->getLinkage();
Anders Carlssonf6b89a12010-02-07 02:03:08 +0000126
John McCallb6bbcc92010-10-15 04:57:14 +0000127 return EmitStaticVarDecl(D, Linkage);
Anders Carlssonf6b89a12010-02-07 02:03:08 +0000128 }
John McCalld931b082010-08-26 03:08:43 +0000129 case SC_Extern:
130 case SC_PrivateExtern:
Lauro Ramos Venanciofea90b82008-02-16 22:30:38 +0000131 // Don't emit it now, allow it to be emitted lazily on its first use.
132 return;
Reid Spencer5f016e22007-07-11 17:01:13 +0000133 }
Daniel Dunbar5466c7b2009-04-14 02:25:56 +0000134
135 assert(0 && "Unknown storage class");
Reid Spencer5f016e22007-07-11 17:01:13 +0000136}
137
Chris Lattner761acc12009-12-05 08:22:11 +0000138static std::string GetStaticDeclName(CodeGenFunction &CGF, const VarDecl &D,
139 const char *Separator) {
140 CodeGenModule &CGM = CGF.CGM;
John McCallf746aa62010-03-19 23:29:14 +0000141 if (CGF.getContext().getLangOptions().CPlusPlus) {
Anders Carlsson9a20d552010-06-22 16:16:50 +0000142 llvm::StringRef Name = CGM.getMangledName(&D);
143 return Name.str();
John McCallf746aa62010-03-19 23:29:14 +0000144 }
Chris Lattner761acc12009-12-05 08:22:11 +0000145
146 std::string ContextName;
Fariborz Jahanianfaa5bfc2010-11-30 23:07:14 +0000147 if (!CGF.CurFuncDecl) {
148 // Better be in a block declared in global scope.
149 const NamedDecl *ND = cast<NamedDecl>(&D);
150 const DeclContext *DC = ND->getDeclContext();
151 if (const BlockDecl *BD = dyn_cast<BlockDecl>(DC)) {
152 MangleBuffer Name;
Peter Collingbourne14110472011-01-13 18:57:25 +0000153 CGM.getBlockMangledName(GlobalDecl(), Name, BD);
Fariborz Jahanianfaa5bfc2010-11-30 23:07:14 +0000154 ContextName = Name.getString();
155 }
156 else
157 assert(0 && "Unknown context for block static var decl");
158 } else if (const FunctionDecl *FD = dyn_cast<FunctionDecl>(CGF.CurFuncDecl)) {
Anders Carlsson9a20d552010-06-22 16:16:50 +0000159 llvm::StringRef Name = CGM.getMangledName(FD);
160 ContextName = Name.str();
John McCallf746aa62010-03-19 23:29:14 +0000161 } else if (isa<ObjCMethodDecl>(CGF.CurFuncDecl))
Chris Lattner761acc12009-12-05 08:22:11 +0000162 ContextName = CGF.CurFn->getName();
163 else
Fariborz Jahanianfaa5bfc2010-11-30 23:07:14 +0000164 assert(0 && "Unknown context for static var decl");
Chris Lattner761acc12009-12-05 08:22:11 +0000165
166 return ContextName + Separator + D.getNameAsString();
167}
168
Daniel Dunbar0096acf2009-02-25 19:24:29 +0000169llvm::GlobalVariable *
John McCallb6bbcc92010-10-15 04:57:14 +0000170CodeGenFunction::CreateStaticVarDecl(const VarDecl &D,
171 const char *Separator,
172 llvm::GlobalValue::LinkageTypes Linkage) {
Chris Lattner8bcfc5b2008-04-06 23:10:54 +0000173 QualType Ty = D.getType();
Eli Friedman3c2b3172008-02-15 12:20:59 +0000174 assert(Ty->isConstantSizeType() && "VLAs can't be static");
Nate Begeman8bd4afe2008-04-19 04:17:09 +0000175
Chris Lattner761acc12009-12-05 08:22:11 +0000176 std::string Name = GetStaticDeclName(*this, D, Separator);
Nate Begeman8bd4afe2008-04-19 04:17:09 +0000177
Daniel Dunbar0096acf2009-02-25 19:24:29 +0000178 const llvm::Type *LTy = CGM.getTypes().ConvertTypeForMem(Ty);
Anders Carlsson41f8a132009-09-26 18:16:06 +0000179 llvm::GlobalVariable *GV =
180 new llvm::GlobalVariable(CGM.getModule(), LTy,
181 Ty.isConstant(getContext()), Linkage,
182 CGM.EmitNullConstant(D.getType()), Name, 0,
Peter Collingbourne207f4d82011-03-18 22:38:29 +0000183 D.isThreadSpecified(),
184 CGM.getContext().getTargetAddressSpace(Ty));
Ken Dyck8b752f12010-01-27 17:10:57 +0000185 GV->setAlignment(getContext().getDeclAlign(&D).getQuantity());
John McCall112c9672010-11-02 21:04:24 +0000186 if (Linkage != llvm::GlobalValue::InternalLinkage)
187 GV->setVisibility(CurFn->getVisibility());
Anders Carlsson41f8a132009-09-26 18:16:06 +0000188 return GV;
Daniel Dunbar0096acf2009-02-25 19:24:29 +0000189}
190
John McCallb6bbcc92010-10-15 04:57:14 +0000191/// AddInitializerToStaticVarDecl - Add the initializer for 'D' to the
Chris Lattner761acc12009-12-05 08:22:11 +0000192/// global variable that has already been created for it. If the initializer
193/// has a different type than GV does, this may free GV and return a different
194/// one. Otherwise it just returns GV.
195llvm::GlobalVariable *
John McCallb6bbcc92010-10-15 04:57:14 +0000196CodeGenFunction::AddInitializerToStaticVarDecl(const VarDecl &D,
197 llvm::GlobalVariable *GV) {
Chris Lattner761acc12009-12-05 08:22:11 +0000198 llvm::Constant *Init = CGM.EmitConstantExpr(D.getInit(), D.getType(), this);
John McCallbf40cb52010-07-15 23:40:35 +0000199
Chris Lattner761acc12009-12-05 08:22:11 +0000200 // If constant emission failed, then this should be a C++ static
201 // initializer.
202 if (!Init) {
203 if (!getContext().getLangOptions().CPlusPlus)
204 CGM.ErrorUnsupported(D.getInit(), "constant l-value expression");
John McCall5cd91b52010-09-08 01:44:27 +0000205 else if (Builder.GetInsertBlock()) {
Anders Carlsson071c8102010-01-26 04:02:23 +0000206 // Since we have a static initializer, this global variable can't
207 // be constant.
208 GV->setConstant(false);
John McCall5cd91b52010-09-08 01:44:27 +0000209
John McCall3030eb82010-11-06 09:44:32 +0000210 EmitCXXGuardedInit(D, GV);
Anders Carlsson071c8102010-01-26 04:02:23 +0000211 }
Chris Lattner761acc12009-12-05 08:22:11 +0000212 return GV;
213 }
John McCallbf40cb52010-07-15 23:40:35 +0000214
Chris Lattner761acc12009-12-05 08:22:11 +0000215 // The initializer may differ in type from the global. Rewrite
216 // the global to match the initializer. (We have to do this
217 // because some types, like unions, can't be completely represented
218 // in the LLVM type system.)
John McCall9c20fa92010-09-03 18:58:50 +0000219 if (GV->getType()->getElementType() != Init->getType()) {
Chris Lattner761acc12009-12-05 08:22:11 +0000220 llvm::GlobalVariable *OldGV = GV;
221
222 GV = new llvm::GlobalVariable(CGM.getModule(), Init->getType(),
223 OldGV->isConstant(),
224 OldGV->getLinkage(), Init, "",
John McCall112c9672010-11-02 21:04:24 +0000225 /*InsertBefore*/ OldGV,
226 D.isThreadSpecified(),
Peter Collingbourne207f4d82011-03-18 22:38:29 +0000227 CGM.getContext().getTargetAddressSpace(D.getType()));
John McCall112c9672010-11-02 21:04:24 +0000228 GV->setVisibility(OldGV->getVisibility());
Chris Lattner761acc12009-12-05 08:22:11 +0000229
230 // Steal the name of the old global
231 GV->takeName(OldGV);
232
233 // Replace all uses of the old global with the new global
234 llvm::Constant *NewPtrForOldDecl =
235 llvm::ConstantExpr::getBitCast(GV, OldGV->getType());
236 OldGV->replaceAllUsesWith(NewPtrForOldDecl);
237
238 // Erase the old global, since it is no longer used.
239 OldGV->eraseFromParent();
240 }
241
242 GV->setInitializer(Init);
243 return GV;
244}
245
John McCallb6bbcc92010-10-15 04:57:14 +0000246void CodeGenFunction::EmitStaticVarDecl(const VarDecl &D,
Anders Carlssonf6b89a12010-02-07 02:03:08 +0000247 llvm::GlobalValue::LinkageTypes Linkage) {
Daniel Dunbara985b312009-02-25 19:45:19 +0000248 llvm::Value *&DMEntry = LocalDeclMap[&D];
249 assert(DMEntry == 0 && "Decl already exists in localdeclmap!");
Mike Stump1eb44332009-09-09 15:08:12 +0000250
John McCallb6bbcc92010-10-15 04:57:14 +0000251 llvm::GlobalVariable *GV = CreateStaticVarDecl(D, ".", Linkage);
Daniel Dunbara985b312009-02-25 19:45:19 +0000252
Daniel Dunbare5731f82009-02-25 20:08:33 +0000253 // Store into LocalDeclMap before generating initializer to handle
254 // circular references.
255 DMEntry = GV;
256
John McCallfe67f3b2010-05-04 20:45:42 +0000257 // We can't have a VLA here, but we can have a pointer to a VLA,
258 // even though that doesn't really make any sense.
Eli Friedmanc62aad82009-04-20 03:54:15 +0000259 // Make sure to evaluate VLA bounds now so that we have them for later.
260 if (D.getType()->isVariablyModifiedType())
261 EmitVLASize(D.getType());
Fariborz Jahanian09349142010-09-07 23:26:17 +0000262
263 // Local static block variables must be treated as globals as they may be
264 // referenced in their RHS initializer block-literal expresion.
265 CGM.setStaticLocalDeclAddress(&D, GV);
Eli Friedmanc62aad82009-04-20 03:54:15 +0000266
Chris Lattner761acc12009-12-05 08:22:11 +0000267 // If this value has an initializer, emit it.
268 if (D.getInit())
John McCallb6bbcc92010-10-15 04:57:14 +0000269 GV = AddInitializerToStaticVarDecl(D, GV);
Nate Begeman8bd4afe2008-04-19 04:17:09 +0000270
Chris Lattner0af95232010-03-10 23:59:59 +0000271 GV->setAlignment(getContext().getDeclAlign(&D).getQuantity());
272
Daniel Dunbar30510ab2009-02-12 23:32:54 +0000273 // FIXME: Merge attribute handling.
Argyrios Kyrtzidis40b598e2009-06-30 02:34:44 +0000274 if (const AnnotateAttr *AA = D.getAttr<AnnotateAttr>()) {
Nate Begeman8bd4afe2008-04-19 04:17:09 +0000275 SourceManager &SM = CGM.getContext().getSourceManager();
276 llvm::Constant *Ann =
Mike Stump1eb44332009-09-09 15:08:12 +0000277 CGM.EmitAnnotateAttr(GV, AA,
Chris Lattnerf7cf85b2009-01-16 07:36:28 +0000278 SM.getInstantiationLineNumber(D.getLocation()));
Nate Begeman8bd4afe2008-04-19 04:17:09 +0000279 CGM.AddAnnotation(Ann);
280 }
281
Argyrios Kyrtzidis40b598e2009-06-30 02:34:44 +0000282 if (const SectionAttr *SA = D.getAttr<SectionAttr>())
Daniel Dunbar30510ab2009-02-12 23:32:54 +0000283 GV->setSection(SA->getName());
Mike Stump1eb44332009-09-09 15:08:12 +0000284
Argyrios Kyrtzidis40b598e2009-06-30 02:34:44 +0000285 if (D.hasAttr<UsedAttr>())
Daniel Dunbar5c61d972009-02-13 22:08:43 +0000286 CGM.AddUsedGlobal(GV);
287
Daniel Dunbare5731f82009-02-25 20:08:33 +0000288 // We may have to cast the constant because of the initializer
289 // mismatch above.
290 //
291 // FIXME: It is really dangerous to store this in the map; if anyone
292 // RAUW's the GV uses of this constant will be invalid.
Eli Friedman26590522008-06-08 01:23:18 +0000293 const llvm::Type *LTy = CGM.getTypes().ConvertTypeForMem(D.getType());
Peter Collingbourne207f4d82011-03-18 22:38:29 +0000294 const llvm::Type *LPtrTy =
295 LTy->getPointerTo(CGM.getContext().getTargetAddressSpace(D.getType()));
Owen Anderson3c4972d2009-07-29 18:54:39 +0000296 DMEntry = llvm::ConstantExpr::getBitCast(GV, LPtrTy);
Sanjiv Gupta686226b2008-06-05 08:59:10 +0000297
298 // Emit global variable debug descriptor for static vars.
Anders Carlssone896d982009-02-13 08:11:52 +0000299 CGDebugInfo *DI = getDebugInfo();
Mike Stump4451bd92009-02-20 00:19:45 +0000300 if (DI) {
Daniel Dunbar66031a52008-10-17 16:15:48 +0000301 DI->setLocation(D.getLocation());
Sanjiv Gupta686226b2008-06-05 08:59:10 +0000302 DI->EmitGlobalVariable(static_cast<llvm::GlobalVariable *>(GV), &D);
303 }
Anders Carlsson1a86b332007-10-17 00:52:43 +0000304}
Mike Stump1eb44332009-09-09 15:08:12 +0000305
John McCallda65ea82010-07-13 20:32:21 +0000306namespace {
John McCall1f0fca52010-07-21 07:22:38 +0000307 struct CallArrayDtor : EHScopeStack::Cleanup {
John McCallda65ea82010-07-13 20:32:21 +0000308 CallArrayDtor(const CXXDestructorDecl *Dtor,
309 const ConstantArrayType *Type,
310 llvm::Value *Loc)
311 : Dtor(Dtor), Type(Type), Loc(Loc) {}
312
313 const CXXDestructorDecl *Dtor;
314 const ConstantArrayType *Type;
315 llvm::Value *Loc;
316
317 void Emit(CodeGenFunction &CGF, bool IsForEH) {
318 QualType BaseElementTy = CGF.getContext().getBaseElementType(Type);
319 const llvm::Type *BasePtr = CGF.ConvertType(BaseElementTy);
320 BasePtr = llvm::PointerType::getUnqual(BasePtr);
321 llvm::Value *BaseAddrPtr = CGF.Builder.CreateBitCast(Loc, BasePtr);
322 CGF.EmitCXXAggrDestructorCall(Dtor, Type, BaseAddrPtr);
323 }
324 };
325
John McCall1f0fca52010-07-21 07:22:38 +0000326 struct CallVarDtor : EHScopeStack::Cleanup {
John McCallda65ea82010-07-13 20:32:21 +0000327 CallVarDtor(const CXXDestructorDecl *Dtor,
328 llvm::Value *NRVOFlag,
329 llvm::Value *Loc)
330 : Dtor(Dtor), NRVOFlag(NRVOFlag), Loc(Loc) {}
331
332 const CXXDestructorDecl *Dtor;
333 llvm::Value *NRVOFlag;
334 llvm::Value *Loc;
335
336 void Emit(CodeGenFunction &CGF, bool IsForEH) {
337 // Along the exceptions path we always execute the dtor.
338 bool NRVO = !IsForEH && NRVOFlag;
339
340 llvm::BasicBlock *SkipDtorBB = 0;
341 if (NRVO) {
342 // If we exited via NRVO, we skip the destructor call.
343 llvm::BasicBlock *RunDtorBB = CGF.createBasicBlock("nrvo.unused");
344 SkipDtorBB = CGF.createBasicBlock("nrvo.skipdtor");
345 llvm::Value *DidNRVO = CGF.Builder.CreateLoad(NRVOFlag, "nrvo.val");
346 CGF.Builder.CreateCondBr(DidNRVO, SkipDtorBB, RunDtorBB);
347 CGF.EmitBlock(RunDtorBB);
348 }
349
350 CGF.EmitCXXDestructorCall(Dtor, Dtor_Complete,
351 /*ForVirtualBase=*/false, Loc);
352
353 if (NRVO) CGF.EmitBlock(SkipDtorBB);
354 }
355 };
356}
357
John McCalld8715092010-07-21 06:13:08 +0000358namespace {
John McCall1f0fca52010-07-21 07:22:38 +0000359 struct CallStackRestore : EHScopeStack::Cleanup {
John McCalld8715092010-07-21 06:13:08 +0000360 llvm::Value *Stack;
361 CallStackRestore(llvm::Value *Stack) : Stack(Stack) {}
362 void Emit(CodeGenFunction &CGF, bool IsForEH) {
363 llvm::Value *V = CGF.Builder.CreateLoad(Stack, "tmp");
364 llvm::Value *F = CGF.CGM.getIntrinsic(llvm::Intrinsic::stackrestore);
365 CGF.Builder.CreateCall(F, V);
366 }
367 };
368
John McCall1f0fca52010-07-21 07:22:38 +0000369 struct CallCleanupFunction : EHScopeStack::Cleanup {
John McCalld8715092010-07-21 06:13:08 +0000370 llvm::Constant *CleanupFn;
371 const CGFunctionInfo &FnInfo;
John McCalld8715092010-07-21 06:13:08 +0000372 const VarDecl &Var;
373
374 CallCleanupFunction(llvm::Constant *CleanupFn, const CGFunctionInfo *Info,
John McCall34695852011-02-22 06:44:22 +0000375 const VarDecl *Var)
376 : CleanupFn(CleanupFn), FnInfo(*Info), Var(*Var) {}
John McCalld8715092010-07-21 06:13:08 +0000377
378 void Emit(CodeGenFunction &CGF, bool IsForEH) {
John McCall34695852011-02-22 06:44:22 +0000379 DeclRefExpr DRE(const_cast<VarDecl*>(&Var), Var.getType(), VK_LValue,
380 SourceLocation());
381 // Compute the address of the local variable, in case it's a byref
382 // or something.
383 llvm::Value *Addr = CGF.EmitDeclRefLValue(&DRE).getAddress();
384
John McCalld8715092010-07-21 06:13:08 +0000385 // In some cases, the type of the function argument will be different from
386 // the type of the pointer. An example of this is
387 // void f(void* arg);
388 // __attribute__((cleanup(f))) void *g;
389 //
390 // To fix this we insert a bitcast here.
391 QualType ArgTy = FnInfo.arg_begin()->type;
392 llvm::Value *Arg =
393 CGF.Builder.CreateBitCast(Addr, CGF.ConvertType(ArgTy));
394
395 CallArgList Args;
Eli Friedman04c9a492011-05-02 17:57:46 +0000396 Args.add(RValue::get(Arg),
397 CGF.getContext().getPointerType(Var.getType()));
John McCalld8715092010-07-21 06:13:08 +0000398 CGF.EmitCall(FnInfo, CleanupFn, ReturnValueSlot(), Args);
399 }
400 };
John McCalld8715092010-07-21 06:13:08 +0000401}
402
Chris Lattner94cd0112010-12-01 02:05:19 +0000403
404/// canEmitInitWithFewStoresAfterMemset - Decide whether we can emit the
405/// non-zero parts of the specified initializer with equal or fewer than
406/// NumStores scalar stores.
407static bool canEmitInitWithFewStoresAfterMemset(llvm::Constant *Init,
408 unsigned &NumStores) {
Chris Lattner70b02942010-12-02 01:58:41 +0000409 // Zero and Undef never requires any extra stores.
410 if (isa<llvm::ConstantAggregateZero>(Init) ||
411 isa<llvm::ConstantPointerNull>(Init) ||
412 isa<llvm::UndefValue>(Init))
413 return true;
414 if (isa<llvm::ConstantInt>(Init) || isa<llvm::ConstantFP>(Init) ||
415 isa<llvm::ConstantVector>(Init) || isa<llvm::BlockAddress>(Init) ||
416 isa<llvm::ConstantExpr>(Init))
417 return Init->isNullValue() || NumStores--;
418
419 // See if we can emit each element.
420 if (isa<llvm::ConstantArray>(Init) || isa<llvm::ConstantStruct>(Init)) {
421 for (unsigned i = 0, e = Init->getNumOperands(); i != e; ++i) {
422 llvm::Constant *Elt = cast<llvm::Constant>(Init->getOperand(i));
423 if (!canEmitInitWithFewStoresAfterMemset(Elt, NumStores))
424 return false;
425 }
426 return true;
427 }
Chris Lattner94cd0112010-12-01 02:05:19 +0000428
429 // Anything else is hard and scary.
430 return false;
431}
432
433/// emitStoresForInitAfterMemset - For inits that
434/// canEmitInitWithFewStoresAfterMemset returned true for, emit the scalar
435/// stores that would be required.
436static void emitStoresForInitAfterMemset(llvm::Constant *Init, llvm::Value *Loc,
John McCall34695852011-02-22 06:44:22 +0000437 bool isVolatile, CGBuilderTy &Builder) {
Chris Lattner94cd0112010-12-01 02:05:19 +0000438 // Zero doesn't require any stores.
Chris Lattner70b02942010-12-02 01:58:41 +0000439 if (isa<llvm::ConstantAggregateZero>(Init) ||
440 isa<llvm::ConstantPointerNull>(Init) ||
441 isa<llvm::UndefValue>(Init))
442 return;
Chris Lattner94cd0112010-12-01 02:05:19 +0000443
Chris Lattner70b02942010-12-02 01:58:41 +0000444 if (isa<llvm::ConstantInt>(Init) || isa<llvm::ConstantFP>(Init) ||
445 isa<llvm::ConstantVector>(Init) || isa<llvm::BlockAddress>(Init) ||
446 isa<llvm::ConstantExpr>(Init)) {
447 if (!Init->isNullValue())
John McCall34695852011-02-22 06:44:22 +0000448 Builder.CreateStore(Init, Loc, isVolatile);
Chris Lattner70b02942010-12-02 01:58:41 +0000449 return;
450 }
Chris Lattner94cd0112010-12-01 02:05:19 +0000451
Chris Lattner70b02942010-12-02 01:58:41 +0000452 assert((isa<llvm::ConstantStruct>(Init) || isa<llvm::ConstantArray>(Init)) &&
453 "Unknown value type!");
454
455 for (unsigned i = 0, e = Init->getNumOperands(); i != e; ++i) {
456 llvm::Constant *Elt = cast<llvm::Constant>(Init->getOperand(i));
457 if (Elt->isNullValue()) continue;
458
459 // Otherwise, get a pointer to the element and emit it.
460 emitStoresForInitAfterMemset(Elt, Builder.CreateConstGEP2_32(Loc, 0, i),
John McCall34695852011-02-22 06:44:22 +0000461 isVolatile, Builder);
Chris Lattner70b02942010-12-02 01:58:41 +0000462 }
Chris Lattner94cd0112010-12-01 02:05:19 +0000463}
464
465
466/// shouldUseMemSetPlusStoresToInitialize - Decide whether we should use memset
467/// plus some stores to initialize a local variable instead of using a memcpy
468/// from a constant global. It is beneficial to use memset if the global is all
469/// zeros, or mostly zeros and large.
470static bool shouldUseMemSetPlusStoresToInitialize(llvm::Constant *Init,
471 uint64_t GlobalSize) {
472 // If a global is all zeros, always use a memset.
473 if (isa<llvm::ConstantAggregateZero>(Init)) return true;
474
475
476 // If a non-zero global is <= 32 bytes, always use a memcpy. If it is large,
477 // do it if it will require 6 or fewer scalar stores.
478 // TODO: Should budget depends on the size? Avoiding a large global warrants
479 // plopping in more stores.
480 unsigned StoreBudget = 6;
481 uint64_t SizeLimit = 32;
482
483 return GlobalSize > SizeLimit &&
484 canEmitInitWithFewStoresAfterMemset(Init, StoreBudget);
485}
486
487
Nick Lewyckya9de3fa2010-12-30 20:21:55 +0000488/// EmitAutoVarDecl - Emit code and set up an entry in LocalDeclMap for a
Reid Spencer5f016e22007-07-11 17:01:13 +0000489/// variable declaration with auto, register, or no storage class specifier.
Chris Lattner2621fd12008-05-08 05:58:21 +0000490/// These turn into simple stack objects, or GlobalValues depending on target.
John McCall34695852011-02-22 06:44:22 +0000491void CodeGenFunction::EmitAutoVarDecl(const VarDecl &D) {
492 AutoVarEmission emission = EmitAutoVarAlloca(D);
493 EmitAutoVarInit(emission);
494 EmitAutoVarCleanups(emission);
495}
Reid Spencer5f016e22007-07-11 17:01:13 +0000496
John McCall34695852011-02-22 06:44:22 +0000497/// EmitAutoVarAlloca - Emit the alloca and debug information for a
498/// local variable. Does not emit initalization or destruction.
499CodeGenFunction::AutoVarEmission
500CodeGenFunction::EmitAutoVarAlloca(const VarDecl &D) {
501 QualType Ty = D.getType();
502
503 AutoVarEmission emission(D);
504
505 bool isByRef = D.hasAttr<BlocksAttr>();
506 emission.IsByRef = isByRef;
507
508 CharUnits alignment = getContext().getDeclAlign(&D);
509 emission.Alignment = alignment;
510
Reid Spencer5f016e22007-07-11 17:01:13 +0000511 llvm::Value *DeclPtr;
Eli Friedman3c2b3172008-02-15 12:20:59 +0000512 if (Ty->isConstantSizeType()) {
Chris Lattner2621fd12008-05-08 05:58:21 +0000513 if (!Target.useGlobalsForAutomaticVariables()) {
John McCall34695852011-02-22 06:44:22 +0000514 bool NRVO = getContext().getLangOptions().ElideConstructors &&
515 D.isNRVOVariable();
516
517 // If this value is a POD array or struct with a statically
518 // determinable constant initializer, there are optimizations we
519 // can do.
520 // TODO: we can potentially constant-evaluate non-POD structs and
521 // arrays as long as the initialization is trivial (e.g. if they
522 // have a non-trivial destructor, but not a non-trivial constructor).
523 if (D.getInit() &&
524 (Ty->isArrayType() || Ty->isRecordType()) && Ty->isPODType() &&
John McCall4204f072010-08-02 21:13:48 +0000525 D.getInit()->isConstantInitializer(getContext(), false)) {
John McCall34695852011-02-22 06:44:22 +0000526
527 // If the variable's a const type, and it's neither an NRVO
528 // candidate nor a __block variable, emit it as a global instead.
529 if (CGM.getCodeGenOpts().MergeAllConstants && Ty.isConstQualified() &&
530 !NRVO && !isByRef) {
Douglas Gregor4707b9a2011-03-06 23:28:21 +0000531 EmitStaticVarDecl(D, llvm::GlobalValue::InternalLinkage);
John McCall34695852011-02-22 06:44:22 +0000532
533 emission.Address = 0; // signal this condition to later callbacks
534 assert(emission.wasEmittedAsGlobal());
535 return emission;
Tanya Lattner59876c22009-11-04 01:18:09 +0000536 }
John McCall34695852011-02-22 06:44:22 +0000537
538 // Otherwise, tell the initialization code that we're in this case.
539 emission.IsConstantAggregate = true;
Tanya Lattner59876c22009-11-04 01:18:09 +0000540 }
541
Douglas Gregord86c4772010-05-15 06:46:45 +0000542 // A normal fixed sized variable becomes an alloca in the entry block,
543 // unless it's an NRVO variable.
Eli Friedmana3460ac2009-03-04 04:25:14 +0000544 const llvm::Type *LTy = ConvertTypeForMem(Ty);
Douglas Gregord86c4772010-05-15 06:46:45 +0000545
546 if (NRVO) {
547 // The named return value optimization: allocate this variable in the
548 // return slot, so that we can elide the copy when returning this
549 // variable (C++0x [class.copy]p34).
550 DeclPtr = ReturnValue;
Douglas Gregor3d91bbc2010-05-17 15:52:46 +0000551
552 if (const RecordType *RecordTy = Ty->getAs<RecordType>()) {
553 if (!cast<CXXRecordDecl>(RecordTy->getDecl())->hasTrivialDestructor()) {
554 // Create a flag that is used to indicate when the NRVO was applied
555 // to this variable. Set it to zero to indicate that NRVO was not
556 // applied.
Chris Lattner4c53dc12010-12-01 01:47:15 +0000557 llvm::Value *Zero = Builder.getFalse();
John McCall34695852011-02-22 06:44:22 +0000558 llvm::Value *NRVOFlag = CreateTempAlloca(Zero->getType(), "nrvo");
Nick Lewyckya03733b2011-02-16 23:59:08 +0000559 EnsureInsertPoint();
Douglas Gregor3d91bbc2010-05-17 15:52:46 +0000560 Builder.CreateStore(Zero, NRVOFlag);
561
562 // Record the NRVO flag for this variable.
563 NRVOFlags[&D] = NRVOFlag;
John McCall34695852011-02-22 06:44:22 +0000564 emission.NRVOFlag = NRVOFlag;
Douglas Gregor3d91bbc2010-05-17 15:52:46 +0000565 }
566 }
Douglas Gregord86c4772010-05-15 06:46:45 +0000567 } else {
568 if (isByRef)
569 LTy = BuildByRefType(&D);
570
571 llvm::AllocaInst *Alloc = CreateTempAlloca(LTy);
572 Alloc->setName(D.getNameAsString());
Mike Stump1eb44332009-09-09 15:08:12 +0000573
John McCall34695852011-02-22 06:44:22 +0000574 CharUnits allocaAlignment = alignment;
Douglas Gregord86c4772010-05-15 06:46:45 +0000575 if (isByRef)
John McCall34695852011-02-22 06:44:22 +0000576 allocaAlignment = std::max(allocaAlignment,
Ken Dyck06f486e2011-01-18 02:01:14 +0000577 getContext().toCharUnitsFromBits(Target.getPointerAlign(0)));
John McCall34695852011-02-22 06:44:22 +0000578 Alloc->setAlignment(allocaAlignment.getQuantity());
Douglas Gregord86c4772010-05-15 06:46:45 +0000579 DeclPtr = Alloc;
580 }
Chris Lattner2621fd12008-05-08 05:58:21 +0000581 } else {
582 // Targets that don't support recursion emit locals as globals.
583 const char *Class =
John McCalld931b082010-08-26 03:08:43 +0000584 D.getStorageClass() == SC_Register ? ".reg." : ".auto.";
John McCallb6bbcc92010-10-15 04:57:14 +0000585 DeclPtr = CreateStaticVarDecl(D, Class,
586 llvm::GlobalValue::InternalLinkage);
Chris Lattner2621fd12008-05-08 05:58:21 +0000587 }
Mike Stump1eb44332009-09-09 15:08:12 +0000588
Daniel Dunbard286f052009-07-19 06:58:07 +0000589 // FIXME: Can this happen?
Anders Carlsson60d35412008-12-20 20:46:34 +0000590 if (Ty->isVariablyModifiedType())
591 EmitVLASize(Ty);
Reid Spencer5f016e22007-07-11 17:01:13 +0000592 } else {
Daniel Dunbard286f052009-07-19 06:58:07 +0000593 EnsureInsertPoint();
594
Anders Carlsson5ecb1b92009-02-09 20:41:50 +0000595 if (!DidCallStackSave) {
Anders Carlsson5d463152008-12-12 07:38:43 +0000596 // Save the stack.
John McCalld16c2cf2011-02-08 08:22:06 +0000597 llvm::Value *Stack = CreateTempAlloca(Int8PtrTy, "saved_stack");
Mike Stump1eb44332009-09-09 15:08:12 +0000598
Anders Carlsson5d463152008-12-12 07:38:43 +0000599 llvm::Value *F = CGM.getIntrinsic(llvm::Intrinsic::stacksave);
600 llvm::Value *V = Builder.CreateCall(F);
Mike Stump1eb44332009-09-09 15:08:12 +0000601
Anders Carlsson5d463152008-12-12 07:38:43 +0000602 Builder.CreateStore(V, Stack);
Anders Carlsson5ecb1b92009-02-09 20:41:50 +0000603
604 DidCallStackSave = true;
Mike Stump1eb44332009-09-09 15:08:12 +0000605
John McCalld8715092010-07-21 06:13:08 +0000606 // Push a cleanup block and restore the stack there.
John McCall3ad32c82011-01-28 08:37:24 +0000607 // FIXME: in general circumstances, this should be an EH cleanup.
John McCall1f0fca52010-07-21 07:22:38 +0000608 EHStack.pushCleanup<CallStackRestore>(NormalCleanup, Stack);
Anders Carlsson5d463152008-12-12 07:38:43 +0000609 }
Mike Stump1eb44332009-09-09 15:08:12 +0000610
Anders Carlsson5d463152008-12-12 07:38:43 +0000611 // Get the element type.
Mike Stump1eb44332009-09-09 15:08:12 +0000612 const llvm::Type *LElemTy = ConvertTypeForMem(Ty);
Peter Collingbourne207f4d82011-03-18 22:38:29 +0000613 const llvm::Type *LElemPtrTy =
614 LElemTy->getPointerTo(CGM.getContext().getTargetAddressSpace(Ty));
Anders Carlsson5d463152008-12-12 07:38:43 +0000615
Anders Carlsson60d35412008-12-20 20:46:34 +0000616 llvm::Value *VLASize = EmitVLASize(Ty);
Anders Carlsson5d463152008-12-12 07:38:43 +0000617
618 // Allocate memory for the array.
Anders Carlsson41f8a132009-09-26 18:16:06 +0000619 llvm::AllocaInst *VLA =
John McCalld16c2cf2011-02-08 08:22:06 +0000620 Builder.CreateAlloca(llvm::Type::getInt8Ty(getLLVMContext()), VLASize, "vla");
John McCall34695852011-02-22 06:44:22 +0000621 VLA->setAlignment(alignment.getQuantity());
Anders Carlsson41f8a132009-09-26 18:16:06 +0000622
Eli Friedman8f39f5e2008-12-20 23:11:59 +0000623 DeclPtr = Builder.CreateBitCast(VLA, LElemPtrTy, "tmp");
Reid Spencer5f016e22007-07-11 17:01:13 +0000624 }
Eli Friedman8f39f5e2008-12-20 23:11:59 +0000625
Reid Spencer5f016e22007-07-11 17:01:13 +0000626 llvm::Value *&DMEntry = LocalDeclMap[&D];
627 assert(DMEntry == 0 && "Decl already exists in localdeclmap!");
628 DMEntry = DeclPtr;
John McCall34695852011-02-22 06:44:22 +0000629 emission.Address = DeclPtr;
Sanjiv Guptacc9b1632008-05-30 10:30:31 +0000630
631 // Emit debug info for local var declaration.
Devang Patelc594abd2011-06-03 19:21:47 +0000632 if (HaveInsertPoint())
633 if (CGDebugInfo *DI = getDebugInfo()) {
634 DI->setLocation(D.getLocation());
635 DI->UpdateLineDirectiveRegion(Builder);
636 DI->EmitStopPoint(Builder);
637 if (Target.useGlobalsForAutomaticVariables()) {
638 DI->EmitGlobalVariable(static_cast<llvm::GlobalVariable *>(DeclPtr), &D);
639 } else
640 DI->EmitDeclareOfAutoVariable(&D, DeclPtr, Builder);
641 }
Sanjiv Guptacc9b1632008-05-30 10:30:31 +0000642
John McCall34695852011-02-22 06:44:22 +0000643 return emission;
644}
645
646/// Determines whether the given __block variable is potentially
647/// captured by the given expression.
648static bool isCapturedBy(const VarDecl &var, const Expr *e) {
649 // Skip the most common kinds of expressions that make
650 // hierarchy-walking expensive.
651 e = e->IgnoreParenCasts();
652
653 if (const BlockExpr *be = dyn_cast<BlockExpr>(e)) {
654 const BlockDecl *block = be->getBlockDecl();
655 for (BlockDecl::capture_const_iterator i = block->capture_begin(),
656 e = block->capture_end(); i != e; ++i) {
657 if (i->getVariable() == &var)
658 return true;
659 }
660
661 // No need to walk into the subexpressions.
662 return false;
663 }
664
665 for (Stmt::const_child_range children = e->children(); children; ++children)
666 if (isCapturedBy(var, cast<Expr>(*children)))
667 return true;
668
669 return false;
670}
671
672void CodeGenFunction::EmitAutoVarInit(const AutoVarEmission &emission) {
John McCall57b3b6a2011-02-22 07:16:58 +0000673 assert(emission.Variable && "emission was not valid!");
674
John McCall34695852011-02-22 06:44:22 +0000675 // If this was emitted as a global constant, we're done.
676 if (emission.wasEmittedAsGlobal()) return;
677
John McCall57b3b6a2011-02-22 07:16:58 +0000678 const VarDecl &D = *emission.Variable;
John McCall34695852011-02-22 06:44:22 +0000679 QualType type = D.getType();
680
Chris Lattner19785962007-07-12 00:39:48 +0000681 // If this local has an initializer, emit it now.
Daniel Dunbard286f052009-07-19 06:58:07 +0000682 const Expr *Init = D.getInit();
683
684 // If we are at an unreachable point, we don't need to emit the initializer
685 // unless it contains a label.
686 if (!HaveInsertPoint()) {
John McCall34695852011-02-22 06:44:22 +0000687 if (!Init || !ContainsLabel(Init)) return;
688 EnsureInsertPoint();
Daniel Dunbard286f052009-07-19 06:58:07 +0000689 }
690
John McCall5af02db2011-03-31 01:59:53 +0000691 // Initialize the structure of a __block variable.
692 if (emission.IsByRef)
693 emitByrefStructureInit(emission);
Anders Carlsson69c68b72009-02-07 23:51:38 +0000694
John McCall34695852011-02-22 06:44:22 +0000695 if (!Init) return;
Mon P Wang3ecd7852010-04-04 03:10:52 +0000696
John McCall5af02db2011-03-31 01:59:53 +0000697 CharUnits alignment = emission.Alignment;
698
John McCall34695852011-02-22 06:44:22 +0000699 // Check whether this is a byref variable that's potentially
700 // captured and moved by its own initializer. If so, we'll need to
701 // emit the initializer first, then copy into the variable.
702 bool capturedByInit = emission.IsByRef && isCapturedBy(D, Init);
703
704 llvm::Value *Loc =
705 capturedByInit ? emission.Address : emission.getObjectAddress(*this);
706
John McCall60d33652011-03-08 09:11:50 +0000707 if (!emission.IsConstantAggregate)
708 return EmitExprAsInit(Init, &D, Loc, alignment, capturedByInit);
709
John McCall34695852011-02-22 06:44:22 +0000710 // If this is a simple aggregate initialization, we can optimize it
711 // in various ways.
John McCall60d33652011-03-08 09:11:50 +0000712 assert(!capturedByInit && "constant init contains a capturing block?");
John McCall34695852011-02-22 06:44:22 +0000713
John McCall60d33652011-03-08 09:11:50 +0000714 bool isVolatile = type.isVolatileQualified();
John McCall34695852011-02-22 06:44:22 +0000715
John McCall60d33652011-03-08 09:11:50 +0000716 llvm::Constant *constant = CGM.EmitConstantExpr(D.getInit(), type, this);
717 assert(constant != 0 && "Wasn't a simple constant init?");
John McCall34695852011-02-22 06:44:22 +0000718
John McCall60d33652011-03-08 09:11:50 +0000719 llvm::Value *SizeVal =
720 llvm::ConstantInt::get(IntPtrTy,
721 getContext().getTypeSizeInChars(type).getQuantity());
John McCall34695852011-02-22 06:44:22 +0000722
John McCall60d33652011-03-08 09:11:50 +0000723 const llvm::Type *BP = Int8PtrTy;
724 if (Loc->getType() != BP)
725 Loc = Builder.CreateBitCast(Loc, BP, "tmp");
Mon P Wang3ecd7852010-04-04 03:10:52 +0000726
John McCall60d33652011-03-08 09:11:50 +0000727 // If the initializer is all or mostly zeros, codegen with memset then do
728 // a few stores afterward.
729 if (shouldUseMemSetPlusStoresToInitialize(constant,
730 CGM.getTargetData().getTypeAllocSize(constant->getType()))) {
731 Builder.CreateMemSet(Loc, llvm::ConstantInt::get(Int8Ty, 0), SizeVal,
732 alignment.getQuantity(), isVolatile);
733 if (!constant->isNullValue()) {
734 Loc = Builder.CreateBitCast(Loc, constant->getType()->getPointerTo());
735 emitStoresForInitAfterMemset(constant, Loc, isVolatile, Builder);
Fariborz Jahanian20e1c7e2010-03-12 21:40:43 +0000736 }
John McCall60d33652011-03-08 09:11:50 +0000737 } else {
738 // Otherwise, create a temporary global with the initializer then
739 // memcpy from the global to the alloca.
740 std::string Name = GetStaticDeclName(*this, D, ".");
741 llvm::GlobalVariable *GV =
742 new llvm::GlobalVariable(CGM.getModule(), constant->getType(), true,
743 llvm::GlobalValue::InternalLinkage,
744 constant, Name, 0, false, 0);
745 GV->setAlignment(alignment.getQuantity());
Eli Friedman460980d2011-05-27 22:32:55 +0000746 GV->setUnnamedAddr(true);
John McCall60d33652011-03-08 09:11:50 +0000747
748 llvm::Value *SrcPtr = GV;
749 if (SrcPtr->getType() != BP)
750 SrcPtr = Builder.CreateBitCast(SrcPtr, BP, "tmp");
751
752 Builder.CreateMemCpy(Loc, SrcPtr, SizeVal, alignment.getQuantity(),
753 isVolatile);
754 }
755}
756
757/// Emit an expression as an initializer for a variable at the given
758/// location. The expression is not necessarily the normal
759/// initializer for the variable, and the address is not necessarily
760/// its normal location.
761///
762/// \param init the initializing expression
763/// \param var the variable to act as if we're initializing
764/// \param loc the address to initialize; its type is a pointer
765/// to the LLVM mapping of the variable's type
766/// \param alignment the alignment of the address
767/// \param capturedByInit true if the variable is a __block variable
768/// whose address is potentially changed by the initializer
769void CodeGenFunction::EmitExprAsInit(const Expr *init,
770 const VarDecl *var,
771 llvm::Value *loc,
772 CharUnits alignment,
773 bool capturedByInit) {
774 QualType type = var->getType();
775 bool isVolatile = type.isVolatileQualified();
776
777 if (type->isReferenceType()) {
778 RValue RV = EmitReferenceBindingToExpr(init, var);
779 if (capturedByInit) loc = BuildBlockByrefAddress(loc, var);
780 EmitStoreOfScalar(RV.getScalarVal(), loc, false,
781 alignment.getQuantity(), type);
John McCall34695852011-02-22 06:44:22 +0000782 } else if (!hasAggregateLLVMType(type)) {
John McCall60d33652011-03-08 09:11:50 +0000783 llvm::Value *V = EmitScalarExpr(init);
784 if (capturedByInit) loc = BuildBlockByrefAddress(loc, var);
785 EmitStoreOfScalar(V, loc, isVolatile, alignment.getQuantity(), type);
John McCall34695852011-02-22 06:44:22 +0000786 } else if (type->isAnyComplexType()) {
John McCall60d33652011-03-08 09:11:50 +0000787 ComplexPairTy complex = EmitComplexExpr(init);
788 if (capturedByInit) loc = BuildBlockByrefAddress(loc, var);
789 StoreComplexToAddr(complex, loc, isVolatile);
John McCall34695852011-02-22 06:44:22 +0000790 } else {
791 // TODO: how can we delay here if D is captured by its initializer?
John McCall60d33652011-03-08 09:11:50 +0000792 EmitAggExpr(init, AggValueSlot::forAddr(loc, isVolatile, true, false));
Fariborz Jahanian20e1c7e2010-03-12 21:40:43 +0000793 }
John McCall34695852011-02-22 06:44:22 +0000794}
John McCallf1549f62010-07-06 01:34:17 +0000795
John McCall34695852011-02-22 06:44:22 +0000796void CodeGenFunction::EmitAutoVarCleanups(const AutoVarEmission &emission) {
John McCall57b3b6a2011-02-22 07:16:58 +0000797 assert(emission.Variable && "emission was not valid!");
798
John McCall34695852011-02-22 06:44:22 +0000799 // If this was emitted as a global constant, we're done.
800 if (emission.wasEmittedAsGlobal()) return;
801
John McCall57b3b6a2011-02-22 07:16:58 +0000802 const VarDecl &D = *emission.Variable;
John McCall34695852011-02-22 06:44:22 +0000803
804 // Handle C++ destruction of variables.
805 if (getLangOptions().CPlusPlus) {
806 QualType type = D.getType();
807 QualType baseType = getContext().getBaseElementType(type);
808 if (const RecordType *RT = baseType->getAs<RecordType>()) {
809 CXXRecordDecl *ClassDecl = cast<CXXRecordDecl>(RT->getDecl());
Douglas Gregorb5b30b92010-05-15 16:39:56 +0000810 if (!ClassDecl->hasTrivialDestructor()) {
Douglas Gregor3d91bbc2010-05-17 15:52:46 +0000811 // Note: We suppress the destructor call when the corresponding NRVO
812 // flag has been set.
John McCall34695852011-02-22 06:44:22 +0000813
814 // Note that for __block variables, we want to destroy the
815 // original stack object, not the possible forwarded object.
816 llvm::Value *Loc = emission.getObjectAddress(*this);
Douglas Gregord86c4772010-05-15 06:46:45 +0000817
Douglas Gregor1d110e02010-07-01 14:13:13 +0000818 const CXXDestructorDecl *D = ClassDecl->getDestructor();
Fariborz Jahanian6ca0b322009-08-03 20:20:07 +0000819 assert(D && "EmitLocalBlockVarDecl - destructor is nul");
Fariborz Jahanian6fba7462009-10-29 16:22:54 +0000820
John McCall34695852011-02-22 06:44:22 +0000821 if (type != baseType) {
822 const ConstantArrayType *Array =
823 getContext().getAsConstantArrayType(type);
824 assert(Array && "types changed without array?");
John McCall1f0fca52010-07-21 07:22:38 +0000825 EHStack.pushCleanup<CallArrayDtor>(NormalAndEHCleanup,
826 D, Array, Loc);
Fariborz Jahanian77996212009-11-04 17:57:40 +0000827 } else {
John McCall1f0fca52010-07-21 07:22:38 +0000828 EHStack.pushCleanup<CallVarDtor>(NormalAndEHCleanup,
John McCall34695852011-02-22 06:44:22 +0000829 D, emission.NRVOFlag, Loc);
Fariborz Jahanian77996212009-11-04 17:57:40 +0000830 }
Fariborz Jahanian6ca0b322009-08-03 20:20:07 +0000831 }
John McCall34695852011-02-22 06:44:22 +0000832 }
Fariborz Jahanian6ca0b322009-08-03 20:20:07 +0000833 }
Mike Stump1eb44332009-09-09 15:08:12 +0000834
John McCall34695852011-02-22 06:44:22 +0000835 // Handle the cleanup attribute.
Argyrios Kyrtzidis40b598e2009-06-30 02:34:44 +0000836 if (const CleanupAttr *CA = D.getAttr<CleanupAttr>()) {
Anders Carlsson69c68b72009-02-07 23:51:38 +0000837 const FunctionDecl *FD = CA->getFunctionDecl();
Mike Stump1eb44332009-09-09 15:08:12 +0000838
John McCall34695852011-02-22 06:44:22 +0000839 llvm::Constant *F = CGM.GetAddrOfFunction(FD);
Anders Carlsson69c68b72009-02-07 23:51:38 +0000840 assert(F && "Could not find function!");
Mike Stump1eb44332009-09-09 15:08:12 +0000841
Anders Carlssoncabec032009-04-26 00:34:20 +0000842 const CGFunctionInfo &Info = CGM.getTypes().getFunctionInfo(FD);
John McCall34695852011-02-22 06:44:22 +0000843 EHStack.pushCleanup<CallCleanupFunction>(NormalAndEHCleanup, F, &Info, &D);
Anders Carlsson69c68b72009-02-07 23:51:38 +0000844 }
Mike Stump797b6322009-03-05 01:23:13 +0000845
John McCall34695852011-02-22 06:44:22 +0000846 // If this is a block variable, call _Block_object_destroy
847 // (on the unforwarded address).
John McCall5af02db2011-03-31 01:59:53 +0000848 if (emission.IsByRef)
849 enterByrefCleanup(emission);
Reid Spencer5f016e22007-07-11 17:01:13 +0000850}
851
Mike Stump1eb44332009-09-09 15:08:12 +0000852/// Emit an alloca (or GlobalValue depending on target)
Chris Lattner2621fd12008-05-08 05:58:21 +0000853/// for the specified parameter and set up LocalDeclMap.
Devang Patel093ac462011-03-03 20:13:15 +0000854void CodeGenFunction::EmitParmDecl(const VarDecl &D, llvm::Value *Arg,
855 unsigned ArgNo) {
Daniel Dunbarb7ec2462008-08-16 03:19:19 +0000856 // FIXME: Why isn't ImplicitParamDecl a ParmVarDecl?
Sanjiv Gupta31fc07d2008-10-31 09:52:39 +0000857 assert((isa<ParmVarDecl>(D) || isa<ImplicitParamDecl>(D)) &&
Daniel Dunbarb7ec2462008-08-16 03:19:19 +0000858 "Invalid argument to EmitParmDecl");
John McCall8178df32011-02-22 22:38:33 +0000859
860 Arg->setName(D.getName());
861
862 // Use better IR generation for certain implicit parameters.
863 if (isa<ImplicitParamDecl>(D)) {
864 // The only implicit argument a block has is its literal.
865 if (BlockInfo) {
866 LocalDeclMap[&D] = Arg;
867
868 if (CGDebugInfo *DI = getDebugInfo()) {
869 DI->setLocation(D.getLocation());
870 DI->EmitDeclareOfBlockLiteralArgVariable(*BlockInfo, Arg, Builder);
871 }
872
873 return;
874 }
875 }
876
Chris Lattner8bcfc5b2008-04-06 23:10:54 +0000877 QualType Ty = D.getType();
Mike Stump1eb44332009-09-09 15:08:12 +0000878
Reid Spencer5f016e22007-07-11 17:01:13 +0000879 llvm::Value *DeclPtr;
Daniel Dunbare86bcf02010-02-08 22:53:07 +0000880 // If this is an aggregate or variable sized value, reuse the input pointer.
881 if (!Ty->isConstantSizeType() ||
882 CodeGenFunction::hasAggregateLLVMType(Ty)) {
Reid Spencer5f016e22007-07-11 17:01:13 +0000883 DeclPtr = Arg;
Reid Spencer5f016e22007-07-11 17:01:13 +0000884 } else {
Daniel Dunbare86bcf02010-02-08 22:53:07 +0000885 // Otherwise, create a temporary to hold the value.
Daniel Dunbar195337d2010-02-09 02:48:28 +0000886 DeclPtr = CreateMemTemp(Ty, D.getName() + ".addr");
Mike Stump1eb44332009-09-09 15:08:12 +0000887
Daniel Dunbare86bcf02010-02-08 22:53:07 +0000888 // Store the initial value into the alloca.
John McCall5936e332011-02-15 09:22:45 +0000889 EmitStoreOfScalar(Arg, DeclPtr, Ty.isVolatileQualified(),
890 getContext().getDeclAlign(&D).getQuantity(), Ty,
891 CGM.getTBAAInfo(Ty));
Reid Spencer5f016e22007-07-11 17:01:13 +0000892 }
893
894 llvm::Value *&DMEntry = LocalDeclMap[&D];
895 assert(DMEntry == 0 && "Decl already exists in localdeclmap!");
896 DMEntry = DeclPtr;
Sanjiv Guptacc9b1632008-05-30 10:30:31 +0000897
898 // Emit debug info for param declaration.
Devang Patelfee53aa2009-10-09 22:06:15 +0000899 if (CGDebugInfo *DI = getDebugInfo()) {
900 DI->setLocation(D.getLocation());
Devang Patel093ac462011-03-03 20:13:15 +0000901 DI->EmitDeclareOfArgVariable(&D, DeclPtr, ArgNo, Builder);
Devang Patelfee53aa2009-10-09 22:06:15 +0000902 }
Reid Spencer5f016e22007-07-11 17:01:13 +0000903}