blob: c095ff96fce30bde4ca68aeb774344919400d388 [file] [log] [blame]
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
14#include "CodeGenFunction.h"
Chandler Carruth55fc8732012-12-04 09:13:33 +000015#include "CGDebugInfo.h"
Peter Collingbourne8c25fc52011-09-19 21:14:35 +000016#include "CGOpenCLRuntime.h"
Chandler Carruth55fc8732012-12-04 09:13:33 +000017#include "CodeGenModule.h"
Daniel Dunbarde7fb842008-08-11 05:00:27 +000018#include "clang/AST/ASTContext.h"
Ken Dyckbdc601b2009-12-22 14:23:30 +000019#include "clang/AST/CharUnits.h"
Daniel Dunbarc4a1dea2008-08-11 05:35:13 +000020#include "clang/AST/Decl.h"
Anders Carlsson19567ee2008-08-25 01:38:19 +000021#include "clang/AST/DeclObjC.h"
Nate Begeman8bd4afe2008-04-19 04:17:09 +000022#include "clang/Basic/SourceManager.h"
Chris Lattner2621fd12008-05-08 05:58:21 +000023#include "clang/Basic/TargetInfo.h"
Chandler Carruth06057ce2010-06-15 23:19:56 +000024#include "clang/Frontend/CodeGenOptions.h"
Chandler Carruth3b844ba2013-01-02 11:45:17 +000025#include "llvm/IR/DataLayout.h"
26#include "llvm/IR/GlobalVariable.h"
27#include "llvm/IR/Intrinsics.h"
28#include "llvm/IR/Type.h"
Reid Spencer5f016e22007-07-11 17:01:13 +000029using namespace clang;
30using namespace CodeGen;
31
32
33void CodeGenFunction::EmitDecl(const Decl &D) {
Reid Spencer5f016e22007-07-11 17:01:13 +000034 switch (D.getKind()) {
Douglas Gregor08688ac2010-04-23 02:02:43 +000035 case Decl::TranslationUnit:
36 case Decl::Namespace:
37 case Decl::UnresolvedUsingTypename:
38 case Decl::ClassTemplateSpecialization:
39 case Decl::ClassTemplatePartialSpecialization:
40 case Decl::TemplateTypeParm:
41 case Decl::UnresolvedUsingValue:
Sean Hunt9a555912010-05-30 07:21:58 +000042 case Decl::NonTypeTemplateParm:
Douglas Gregor08688ac2010-04-23 02:02:43 +000043 case Decl::CXXMethod:
44 case Decl::CXXConstructor:
45 case Decl::CXXDestructor:
46 case Decl::CXXConversion:
47 case Decl::Field:
Francois Pichet41f5e662010-11-21 06:49:41 +000048 case Decl::IndirectField:
Douglas Gregor08688ac2010-04-23 02:02:43 +000049 case Decl::ObjCIvar:
Eric Christophere1f54902011-08-23 22:38:00 +000050 case Decl::ObjCAtDefsField:
Chris Lattneraa9fc462007-10-08 21:37:32 +000051 case Decl::ParmVar:
Douglas Gregor08688ac2010-04-23 02:02:43 +000052 case Decl::ImplicitParam:
53 case Decl::ClassTemplate:
54 case Decl::FunctionTemplate:
Richard Smith3e4c6c42011-05-05 21:57:07 +000055 case Decl::TypeAliasTemplate:
Douglas Gregor08688ac2010-04-23 02:02:43 +000056 case Decl::TemplateTemplateParm:
57 case Decl::ObjCMethod:
58 case Decl::ObjCCategory:
59 case Decl::ObjCProtocol:
60 case Decl::ObjCInterface:
61 case Decl::ObjCCategoryImpl:
62 case Decl::ObjCImplementation:
63 case Decl::ObjCProperty:
64 case Decl::ObjCCompatibleAlias:
Abramo Bagnara6206d532010-06-05 05:09:32 +000065 case Decl::AccessSpec:
Douglas Gregor08688ac2010-04-23 02:02:43 +000066 case Decl::LinkageSpec:
67 case Decl::ObjCPropertyImpl:
Douglas Gregor08688ac2010-04-23 02:02:43 +000068 case Decl::FileScopeAsm:
69 case Decl::Friend:
70 case Decl::FriendTemplate:
71 case Decl::Block:
Francois Pichetaf0f4d02011-08-14 03:52:19 +000072 case Decl::ClassScopeFunctionSpecialization:
David Blaikieb219cfc2011-09-23 05:06:16 +000073 llvm_unreachable("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:
David Blaikiec8c24272013-02-02 00:39:32 +000081 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;
Douglas Gregor15de72c2011-12-02 23:23:56 +000085 case Decl::Import:
Alexey Bataevc6400582013-03-22 06:34:35 +000086 case Decl::OMPThreadPrivate:
Michael Han684aa732013-02-22 17:15:32 +000087 case Decl::Empty:
Reid Spencer5f016e22007-07-11 17:01:13 +000088 // None of these decls require codegen support.
89 return;
David Blaikiec8c24272013-02-02 00:39:32 +000090
Daniel Dunbar662174c82008-08-29 17:28:43 +000091 case Decl::Var: {
92 const VarDecl &VD = cast<VarDecl>(D);
John McCallb6bbcc92010-10-15 04:57:14 +000093 assert(VD.isLocalVarDecl() &&
Daniel Dunbar662174c82008-08-29 17:28:43 +000094 "Should not see file-scope variables inside a function!");
John McCallb6bbcc92010-10-15 04:57:14 +000095 return EmitVarDecl(VD);
Reid Spencer5f016e22007-07-11 17:01:13 +000096 }
Mike Stump1eb44332009-09-09 15:08:12 +000097
Richard Smith162e1c12011-04-15 14:24:37 +000098 case Decl::Typedef: // typedef int X;
99 case Decl::TypeAlias: { // using X = int; [C++0x]
100 const TypedefNameDecl &TD = cast<TypedefNameDecl>(D);
Anders Carlssonfcdbb932008-12-20 21:51:53 +0000101 QualType Ty = TD.getUnderlyingType();
Mike Stump1eb44332009-09-09 15:08:12 +0000102
Anders Carlssonfcdbb932008-12-20 21:51:53 +0000103 if (Ty->isVariablyModifiedType())
John McCallbc8d40d2011-06-24 21:55:10 +0000104 EmitVariablyModifiedType(Ty);
Anders Carlssonfcdbb932008-12-20 21:51:53 +0000105 }
Daniel Dunbar662174c82008-08-29 17:28:43 +0000106 }
Reid Spencer5f016e22007-07-11 17:01:13 +0000107}
108
John McCallb6bbcc92010-10-15 04:57:14 +0000109/// EmitVarDecl - This method handles emission of any variable declaration
Reid Spencer5f016e22007-07-11 17:01:13 +0000110/// inside a function, including static vars etc.
John McCallb6bbcc92010-10-15 04:57:14 +0000111void CodeGenFunction::EmitVarDecl(const VarDecl &D) {
Rafael Espindola0db661e2012-12-21 01:21:33 +0000112 switch (D.getStorageClassAsWritten()) {
John McCalld931b082010-08-26 03:08:43 +0000113 case SC_None:
114 case SC_Auto:
115 case SC_Register:
John McCallb6bbcc92010-10-15 04:57:14 +0000116 return EmitAutoVarDecl(D);
John McCalld931b082010-08-26 03:08:43 +0000117 case SC_Static: {
Eric Christophere1f54902011-08-23 22:38:00 +0000118 llvm::GlobalValue::LinkageTypes Linkage =
Anders Carlssonf6b89a12010-02-07 02:03:08 +0000119 llvm::GlobalValue::InternalLinkage;
120
John McCall8b242332010-05-25 04:30:21 +0000121 // If the function definition has some sort of weak linkage, its
122 // static variables should also be weak so that they get properly
123 // uniqued. We can't do this in C, though, because there's no
124 // standard way to agree on which variables are the same (i.e.
125 // there's no mangling).
Richard Smith7edf9e32012-11-01 22:30:59 +0000126 if (getLangOpts().CPlusPlus)
John McCall8b242332010-05-25 04:30:21 +0000127 if (llvm::GlobalValue::isWeakForLinker(CurFn->getLinkage()))
128 Linkage = CurFn->getLinkage();
Eric Christophere1f54902011-08-23 22:38:00 +0000129
John McCallb6bbcc92010-10-15 04:57:14 +0000130 return EmitStaticVarDecl(D, Linkage);
Anders Carlssonf6b89a12010-02-07 02:03:08 +0000131 }
John McCalld931b082010-08-26 03:08:43 +0000132 case SC_Extern:
133 case SC_PrivateExtern:
Lauro Ramos Venanciofea90b82008-02-16 22:30:38 +0000134 // Don't emit it now, allow it to be emitted lazily on its first use.
135 return;
Peter Collingbourne8c25fc52011-09-19 21:14:35 +0000136 case SC_OpenCLWorkGroupLocal:
137 return CGM.getOpenCLRuntime().EmitWorkGroupLocalVarDecl(*this, D);
Reid Spencer5f016e22007-07-11 17:01:13 +0000138 }
Daniel Dunbar5466c7b2009-04-14 02:25:56 +0000139
David Blaikieb219cfc2011-09-23 05:06:16 +0000140 llvm_unreachable("Unknown storage class");
Reid Spencer5f016e22007-07-11 17:01:13 +0000141}
142
Chris Lattner761acc12009-12-05 08:22:11 +0000143static std::string GetStaticDeclName(CodeGenFunction &CGF, const VarDecl &D,
144 const char *Separator) {
145 CodeGenModule &CGM = CGF.CGM;
Richard Smith7edf9e32012-11-01 22:30:59 +0000146 if (CGF.getLangOpts().CPlusPlus) {
Chris Lattner5f9e2722011-07-23 10:55:15 +0000147 StringRef Name = CGM.getMangledName(&D);
Anders Carlsson9a20d552010-06-22 16:16:50 +0000148 return Name.str();
John McCallf746aa62010-03-19 23:29:14 +0000149 }
Eric Christophere1f54902011-08-23 22:38:00 +0000150
Chris Lattner761acc12009-12-05 08:22:11 +0000151 std::string ContextName;
Fariborz Jahanianfaa5bfc2010-11-30 23:07:14 +0000152 if (!CGF.CurFuncDecl) {
153 // Better be in a block declared in global scope.
154 const NamedDecl *ND = cast<NamedDecl>(&D);
155 const DeclContext *DC = ND->getDeclContext();
156 if (const BlockDecl *BD = dyn_cast<BlockDecl>(DC)) {
157 MangleBuffer Name;
Peter Collingbourne14110472011-01-13 18:57:25 +0000158 CGM.getBlockMangledName(GlobalDecl(), Name, BD);
Fariborz Jahanianfaa5bfc2010-11-30 23:07:14 +0000159 ContextName = Name.getString();
160 }
161 else
David Blaikieb219cfc2011-09-23 05:06:16 +0000162 llvm_unreachable("Unknown context for block static var decl");
Fariborz Jahanianfaa5bfc2010-11-30 23:07:14 +0000163 } else if (const FunctionDecl *FD = dyn_cast<FunctionDecl>(CGF.CurFuncDecl)) {
Chris Lattner5f9e2722011-07-23 10:55:15 +0000164 StringRef Name = CGM.getMangledName(FD);
Anders Carlsson9a20d552010-06-22 16:16:50 +0000165 ContextName = Name.str();
John McCallf746aa62010-03-19 23:29:14 +0000166 } else if (isa<ObjCMethodDecl>(CGF.CurFuncDecl))
Chris Lattner761acc12009-12-05 08:22:11 +0000167 ContextName = CGF.CurFn->getName();
168 else
David Blaikieb219cfc2011-09-23 05:06:16 +0000169 llvm_unreachable("Unknown context for static var decl");
Eric Christophere1f54902011-08-23 22:38:00 +0000170
Chris Lattner761acc12009-12-05 08:22:11 +0000171 return ContextName + Separator + D.getNameAsString();
172}
173
Chandler Carruth0f30a122012-03-30 19:44:53 +0000174llvm::GlobalVariable *
John McCallb6bbcc92010-10-15 04:57:14 +0000175CodeGenFunction::CreateStaticVarDecl(const VarDecl &D,
176 const char *Separator,
177 llvm::GlobalValue::LinkageTypes Linkage) {
Chris Lattner8bcfc5b2008-04-06 23:10:54 +0000178 QualType Ty = D.getType();
Eli Friedman3c2b3172008-02-15 12:20:59 +0000179 assert(Ty->isConstantSizeType() && "VLAs can't be static");
Nate Begeman8bd4afe2008-04-19 04:17:09 +0000180
Benjamin Kramer5c247db2011-11-20 21:05:04 +0000181 // Use the label if the variable is renamed with the asm-label extension.
182 std::string Name;
Benjamin Kramerc3c8f222011-11-21 15:47:23 +0000183 if (D.hasAttr<AsmLabelAttr>())
184 Name = CGM.getMangledName(&D);
185 else
Benjamin Kramer5c247db2011-11-20 21:05:04 +0000186 Name = GetStaticDeclName(*this, D, Separator);
Nate Begeman8bd4afe2008-04-19 04:17:09 +0000187
Chris Lattner2acc6e32011-07-18 04:24:23 +0000188 llvm::Type *LTy = CGM.getTypes().ConvertTypeForMem(Ty);
Peter Collingbourne1aba7782012-08-28 20:37:10 +0000189 unsigned AddrSpace =
190 CGM.GetGlobalVarAddressSpace(&D, CGM.getContext().getTargetAddressSpace(Ty));
Anders Carlsson41f8a132009-09-26 18:16:06 +0000191 llvm::GlobalVariable *GV =
192 new llvm::GlobalVariable(CGM.getModule(), LTy,
193 Ty.isConstant(getContext()), Linkage,
Hans Wennborgde981f32012-06-28 08:01:44 +0000194 CGM.EmitNullConstant(D.getType()), Name, 0,
195 llvm::GlobalVariable::NotThreadLocal,
Peter Collingbourne1aba7782012-08-28 20:37:10 +0000196 AddrSpace);
Ken Dyck8b752f12010-01-27 17:10:57 +0000197 GV->setAlignment(getContext().getDeclAlign(&D).getQuantity());
John McCall112c9672010-11-02 21:04:24 +0000198 if (Linkage != llvm::GlobalValue::InternalLinkage)
199 GV->setVisibility(CurFn->getVisibility());
Hans Wennborgde981f32012-06-28 08:01:44 +0000200
201 if (D.isThreadSpecified())
202 CGM.setTLSMode(GV, D);
203
Anders Carlsson41f8a132009-09-26 18:16:06 +0000204 return GV;
Daniel Dunbar0096acf2009-02-25 19:24:29 +0000205}
206
Richard Smith7ca48502012-02-13 22:16:19 +0000207/// hasNontrivialDestruction - Determine whether a type's destruction is
208/// non-trivial. If so, and the variable uses static initialization, we must
209/// register its destructor to run on exit.
210static bool hasNontrivialDestruction(QualType T) {
211 CXXRecordDecl *RD = T->getBaseElementTypeUnsafe()->getAsCXXRecordDecl();
212 return RD && !RD->hasTrivialDestructor();
213}
214
Chandler Carruth0f30a122012-03-30 19:44:53 +0000215/// AddInitializerToStaticVarDecl - Add the initializer for 'D' to the
216/// global variable that has already been created for it. If the initializer
217/// has a different type than GV does, this may free GV and return a different
218/// one. Otherwise it just returns GV.
219llvm::GlobalVariable *
John McCallb6bbcc92010-10-15 04:57:14 +0000220CodeGenFunction::AddInitializerToStaticVarDecl(const VarDecl &D,
Chandler Carruth0f30a122012-03-30 19:44:53 +0000221 llvm::GlobalVariable *GV) {
222 llvm::Constant *Init = CGM.EmitConstantInit(D, this);
John McCallbf40cb52010-07-15 23:40:35 +0000223
Chris Lattner761acc12009-12-05 08:22:11 +0000224 // If constant emission failed, then this should be a C++ static
225 // initializer.
Chandler Carruth0f30a122012-03-30 19:44:53 +0000226 if (!Init) {
Richard Smith7edf9e32012-11-01 22:30:59 +0000227 if (!getLangOpts().CPlusPlus)
Chris Lattner761acc12009-12-05 08:22:11 +0000228 CGM.ErrorUnsupported(D.getInit(), "constant l-value expression");
John McCall5cd91b52010-09-08 01:44:27 +0000229 else if (Builder.GetInsertBlock()) {
Eric Christophere1f54902011-08-23 22:38:00 +0000230 // Since we have a static initializer, this global variable can't
Anders Carlsson071c8102010-01-26 04:02:23 +0000231 // be constant.
Chandler Carruth0f30a122012-03-30 19:44:53 +0000232 GV->setConstant(false);
John McCall5cd91b52010-09-08 01:44:27 +0000233
Chandler Carruth0f30a122012-03-30 19:44:53 +0000234 EmitCXXGuardedInit(D, GV, /*PerformInit*/true);
Anders Carlsson071c8102010-01-26 04:02:23 +0000235 }
Chandler Carruth0f30a122012-03-30 19:44:53 +0000236 return GV;
Chris Lattner761acc12009-12-05 08:22:11 +0000237 }
John McCallbf40cb52010-07-15 23:40:35 +0000238
Chris Lattner761acc12009-12-05 08:22:11 +0000239 // The initializer may differ in type from the global. Rewrite
240 // the global to match the initializer. (We have to do this
241 // because some types, like unions, can't be completely represented
242 // in the LLVM type system.)
Chandler Carruth0f30a122012-03-30 19:44:53 +0000243 if (GV->getType()->getElementType() != Init->getType()) {
244 llvm::GlobalVariable *OldGV = GV;
245
246 GV = new llvm::GlobalVariable(CGM.getModule(), Init->getType(),
247 OldGV->isConstant(),
248 OldGV->getLinkage(), Init, "",
249 /*InsertBefore*/ OldGV,
Hans Wennborg5e2d5de2012-06-23 11:51:46 +0000250 OldGV->getThreadLocalMode(),
Chandler Carruth0f30a122012-03-30 19:44:53 +0000251 CGM.getContext().getTargetAddressSpace(D.getType()));
252 GV->setVisibility(OldGV->getVisibility());
Eric Christophere1f54902011-08-23 22:38:00 +0000253
Chris Lattner761acc12009-12-05 08:22:11 +0000254 // Steal the name of the old global
Chandler Carruth0f30a122012-03-30 19:44:53 +0000255 GV->takeName(OldGV);
Eric Christophere1f54902011-08-23 22:38:00 +0000256
Chris Lattner761acc12009-12-05 08:22:11 +0000257 // Replace all uses of the old global with the new global
Chandler Carruth0f30a122012-03-30 19:44:53 +0000258 llvm::Constant *NewPtrForOldDecl =
259 llvm::ConstantExpr::getBitCast(GV, OldGV->getType());
260 OldGV->replaceAllUsesWith(NewPtrForOldDecl);
Eric Christophere1f54902011-08-23 22:38:00 +0000261
Chris Lattner761acc12009-12-05 08:22:11 +0000262 // Erase the old global, since it is no longer used.
Chandler Carruth0f30a122012-03-30 19:44:53 +0000263 OldGV->eraseFromParent();
Chris Lattner761acc12009-12-05 08:22:11 +0000264 }
Eric Christophere1f54902011-08-23 22:38:00 +0000265
Chandler Carruth0f30a122012-03-30 19:44:53 +0000266 GV->setConstant(CGM.isTypeConstant(D.getType(), true));
267 GV->setInitializer(Init);
Richard Smith7ca48502012-02-13 22:16:19 +0000268
269 if (hasNontrivialDestruction(D.getType())) {
270 // We have a constant initializer, but a nontrivial destructor. We still
271 // need to perform a guarded "initialization" in order to register the
Richard Smitha9b21d22012-02-17 06:48:11 +0000272 // destructor.
Chandler Carruth0f30a122012-03-30 19:44:53 +0000273 EmitCXXGuardedInit(D, GV, /*PerformInit*/false);
Richard Smith7ca48502012-02-13 22:16:19 +0000274 }
275
Chandler Carruth0f30a122012-03-30 19:44:53 +0000276 return GV;
Chris Lattner761acc12009-12-05 08:22:11 +0000277}
278
John McCallb6bbcc92010-10-15 04:57:14 +0000279void CodeGenFunction::EmitStaticVarDecl(const VarDecl &D,
Anders Carlssonf6b89a12010-02-07 02:03:08 +0000280 llvm::GlobalValue::LinkageTypes Linkage) {
Chandler Carruth0f30a122012-03-30 19:44:53 +0000281 llvm::Value *&DMEntry = LocalDeclMap[&D];
282 assert(DMEntry == 0 && "Decl already exists in localdeclmap!");
Mike Stump1eb44332009-09-09 15:08:12 +0000283
John McCall355bba72012-03-30 21:00:39 +0000284 // Check to see if we already have a global variable for this
285 // declaration. This can happen when double-emitting function
286 // bodies, e.g. with complete and base constructors.
287 llvm::Constant *addr =
288 CGM.getStaticLocalDeclAddress(&D);
289
290 llvm::GlobalVariable *var;
291 if (addr) {
292 var = cast<llvm::GlobalVariable>(addr->stripPointerCasts());
293 } else {
294 addr = var = CreateStaticVarDecl(D, ".", Linkage);
295 }
Daniel Dunbara985b312009-02-25 19:45:19 +0000296
Daniel Dunbare5731f82009-02-25 20:08:33 +0000297 // Store into LocalDeclMap before generating initializer to handle
298 // circular references.
John McCall355bba72012-03-30 21:00:39 +0000299 DMEntry = addr;
300 CGM.setStaticLocalDeclAddress(&D, addr);
Daniel Dunbare5731f82009-02-25 20:08:33 +0000301
John McCallfe67f3b2010-05-04 20:45:42 +0000302 // We can't have a VLA here, but we can have a pointer to a VLA,
303 // even though that doesn't really make any sense.
Eli Friedmanc62aad82009-04-20 03:54:15 +0000304 // Make sure to evaluate VLA bounds now so that we have them for later.
305 if (D.getType()->isVariablyModifiedType())
John McCallbc8d40d2011-06-24 21:55:10 +0000306 EmitVariablyModifiedType(D.getType());
Eric Christophere1f54902011-08-23 22:38:00 +0000307
John McCall355bba72012-03-30 21:00:39 +0000308 // Save the type in case adding the initializer forces a type change.
309 llvm::Type *expectedType = addr->getType();
Eli Friedmanc62aad82009-04-20 03:54:15 +0000310
Chris Lattner761acc12009-12-05 08:22:11 +0000311 // If this value has an initializer, emit it.
312 if (D.getInit())
John McCall355bba72012-03-30 21:00:39 +0000313 var = AddInitializerToStaticVarDecl(D, var);
Nate Begeman8bd4afe2008-04-19 04:17:09 +0000314
John McCall355bba72012-03-30 21:00:39 +0000315 var->setAlignment(getContext().getDeclAlign(&D).getQuantity());
Chris Lattner0af95232010-03-10 23:59:59 +0000316
Julien Lerouge77f68bb2011-09-09 22:41:49 +0000317 if (D.hasAttr<AnnotateAttr>())
John McCall355bba72012-03-30 21:00:39 +0000318 CGM.AddGlobalAnnotations(&D, var);
Nate Begeman8bd4afe2008-04-19 04:17:09 +0000319
Argyrios Kyrtzidis40b598e2009-06-30 02:34:44 +0000320 if (const SectionAttr *SA = D.getAttr<SectionAttr>())
John McCall355bba72012-03-30 21:00:39 +0000321 var->setSection(SA->getName());
Mike Stump1eb44332009-09-09 15:08:12 +0000322
Argyrios Kyrtzidis40b598e2009-06-30 02:34:44 +0000323 if (D.hasAttr<UsedAttr>())
John McCall355bba72012-03-30 21:00:39 +0000324 CGM.AddUsedGlobal(var);
Daniel Dunbar5c61d972009-02-13 22:08:43 +0000325
Chandler Carruth0f30a122012-03-30 19:44:53 +0000326 // We may have to cast the constant because of the initializer
327 // mismatch above.
328 //
329 // FIXME: It is really dangerous to store this in the map; if anyone
330 // RAUW's the GV uses of this constant will be invalid.
John McCall355bba72012-03-30 21:00:39 +0000331 llvm::Constant *castedAddr = llvm::ConstantExpr::getBitCast(var, expectedType);
332 DMEntry = castedAddr;
333 CGM.setStaticLocalDeclAddress(&D, castedAddr);
Sanjiv Gupta686226b2008-06-05 08:59:10 +0000334
335 // Emit global variable debug descriptor for static vars.
Anders Carlssone896d982009-02-13 08:11:52 +0000336 CGDebugInfo *DI = getDebugInfo();
Alexey Samsonovfd00eec2012-05-04 07:39:27 +0000337 if (DI &&
Douglas Gregor4cdad312012-10-23 20:05:01 +0000338 CGM.getCodeGenOpts().getDebugInfo() >= CodeGenOptions::LimitedDebugInfo) {
Daniel Dunbar66031a52008-10-17 16:15:48 +0000339 DI->setLocation(D.getLocation());
John McCall355bba72012-03-30 21:00:39 +0000340 DI->EmitGlobalVariable(var, &D);
Sanjiv Gupta686226b2008-06-05 08:59:10 +0000341 }
Anders Carlsson1a86b332007-10-17 00:52:43 +0000342}
Mike Stump1eb44332009-09-09 15:08:12 +0000343
John McCallda65ea82010-07-13 20:32:21 +0000344namespace {
John McCallbdc4d802011-07-09 01:37:26 +0000345 struct DestroyObject : EHScopeStack::Cleanup {
346 DestroyObject(llvm::Value *addr, QualType type,
John McCall2673c682011-07-11 08:38:19 +0000347 CodeGenFunction::Destroyer *destroyer,
348 bool useEHCleanupForArray)
Peter Collingbourne516bbd42012-01-26 03:33:36 +0000349 : addr(addr), type(type), destroyer(destroyer),
John McCall2673c682011-07-11 08:38:19 +0000350 useEHCleanupForArray(useEHCleanupForArray) {}
John McCallda65ea82010-07-13 20:32:21 +0000351
John McCallbdc4d802011-07-09 01:37:26 +0000352 llvm::Value *addr;
353 QualType type;
Peter Collingbourne516bbd42012-01-26 03:33:36 +0000354 CodeGenFunction::Destroyer *destroyer;
John McCall2673c682011-07-11 08:38:19 +0000355 bool useEHCleanupForArray;
John McCallda65ea82010-07-13 20:32:21 +0000356
John McCallad346f42011-07-12 20:27:29 +0000357 void Emit(CodeGenFunction &CGF, Flags flags) {
John McCall2673c682011-07-11 08:38:19 +0000358 // Don't use an EH cleanup recursively from an EH cleanup.
John McCallad346f42011-07-12 20:27:29 +0000359 bool useEHCleanupForArray =
360 flags.isForNormalCleanup() && this->useEHCleanupForArray;
John McCall2673c682011-07-11 08:38:19 +0000361
362 CGF.emitDestroy(addr, type, destroyer, useEHCleanupForArray);
John McCallda65ea82010-07-13 20:32:21 +0000363 }
364 };
365
John McCallbdc4d802011-07-09 01:37:26 +0000366 struct DestroyNRVOVariable : EHScopeStack::Cleanup {
367 DestroyNRVOVariable(llvm::Value *addr,
368 const CXXDestructorDecl *Dtor,
369 llvm::Value *NRVOFlag)
370 : Dtor(Dtor), NRVOFlag(NRVOFlag), Loc(addr) {}
John McCallda65ea82010-07-13 20:32:21 +0000371
372 const CXXDestructorDecl *Dtor;
373 llvm::Value *NRVOFlag;
374 llvm::Value *Loc;
375
John McCallad346f42011-07-12 20:27:29 +0000376 void Emit(CodeGenFunction &CGF, Flags flags) {
John McCallda65ea82010-07-13 20:32:21 +0000377 // Along the exceptions path we always execute the dtor.
John McCallad346f42011-07-12 20:27:29 +0000378 bool NRVO = flags.isForNormalCleanup() && NRVOFlag;
John McCallda65ea82010-07-13 20:32:21 +0000379
380 llvm::BasicBlock *SkipDtorBB = 0;
381 if (NRVO) {
382 // If we exited via NRVO, we skip the destructor call.
383 llvm::BasicBlock *RunDtorBB = CGF.createBasicBlock("nrvo.unused");
384 SkipDtorBB = CGF.createBasicBlock("nrvo.skipdtor");
385 llvm::Value *DidNRVO = CGF.Builder.CreateLoad(NRVOFlag, "nrvo.val");
386 CGF.Builder.CreateCondBr(DidNRVO, SkipDtorBB, RunDtorBB);
387 CGF.EmitBlock(RunDtorBB);
388 }
Eric Christophere1f54902011-08-23 22:38:00 +0000389
John McCallda65ea82010-07-13 20:32:21 +0000390 CGF.EmitCXXDestructorCall(Dtor, Dtor_Complete,
Douglas Gregor378e1e72013-01-31 05:50:40 +0000391 /*ForVirtualBase=*/false,
392 /*Delegating=*/false,
393 Loc);
John McCallda65ea82010-07-13 20:32:21 +0000394
395 if (NRVO) CGF.EmitBlock(SkipDtorBB);
396 }
397 };
John McCallda65ea82010-07-13 20:32:21 +0000398
John McCall1f0fca52010-07-21 07:22:38 +0000399 struct CallStackRestore : EHScopeStack::Cleanup {
John McCalld8715092010-07-21 06:13:08 +0000400 llvm::Value *Stack;
401 CallStackRestore(llvm::Value *Stack) : Stack(Stack) {}
John McCallad346f42011-07-12 20:27:29 +0000402 void Emit(CodeGenFunction &CGF, Flags flags) {
Benjamin Kramer578faa82011-09-27 21:06:10 +0000403 llvm::Value *V = CGF.Builder.CreateLoad(Stack);
John McCalld8715092010-07-21 06:13:08 +0000404 llvm::Value *F = CGF.CGM.getIntrinsic(llvm::Intrinsic::stackrestore);
405 CGF.Builder.CreateCall(F, V);
406 }
407 };
408
John McCall0c24c802011-06-24 23:21:27 +0000409 struct ExtendGCLifetime : EHScopeStack::Cleanup {
410 const VarDecl &Var;
411 ExtendGCLifetime(const VarDecl *var) : Var(*var) {}
412
John McCallad346f42011-07-12 20:27:29 +0000413 void Emit(CodeGenFunction &CGF, Flags flags) {
John McCall0c24c802011-06-24 23:21:27 +0000414 // Compute the address of the local variable, in case it's a
415 // byref or something.
John McCallf4b88a42012-03-10 09:33:50 +0000416 DeclRefExpr DRE(const_cast<VarDecl*>(&Var), false,
417 Var.getType(), VK_LValue, SourceLocation());
John McCall0c24c802011-06-24 23:21:27 +0000418 llvm::Value *value = CGF.EmitLoadOfScalar(CGF.EmitDeclRefLValue(&DRE));
419 CGF.EmitExtendGCLifetime(value);
420 }
421 };
422
John McCall1f0fca52010-07-21 07:22:38 +0000423 struct CallCleanupFunction : EHScopeStack::Cleanup {
John McCalld8715092010-07-21 06:13:08 +0000424 llvm::Constant *CleanupFn;
425 const CGFunctionInfo &FnInfo;
John McCalld8715092010-07-21 06:13:08 +0000426 const VarDecl &Var;
Eric Christophere1f54902011-08-23 22:38:00 +0000427
John McCalld8715092010-07-21 06:13:08 +0000428 CallCleanupFunction(llvm::Constant *CleanupFn, const CGFunctionInfo *Info,
John McCall34695852011-02-22 06:44:22 +0000429 const VarDecl *Var)
430 : CleanupFn(CleanupFn), FnInfo(*Info), Var(*Var) {}
John McCalld8715092010-07-21 06:13:08 +0000431
John McCallad346f42011-07-12 20:27:29 +0000432 void Emit(CodeGenFunction &CGF, Flags flags) {
John McCallf4b88a42012-03-10 09:33:50 +0000433 DeclRefExpr DRE(const_cast<VarDecl*>(&Var), false,
434 Var.getType(), VK_LValue, SourceLocation());
John McCall34695852011-02-22 06:44:22 +0000435 // Compute the address of the local variable, in case it's a byref
436 // or something.
437 llvm::Value *Addr = CGF.EmitDeclRefLValue(&DRE).getAddress();
438
John McCalld8715092010-07-21 06:13:08 +0000439 // In some cases, the type of the function argument will be different from
440 // the type of the pointer. An example of this is
441 // void f(void* arg);
442 // __attribute__((cleanup(f))) void *g;
443 //
444 // To fix this we insert a bitcast here.
445 QualType ArgTy = FnInfo.arg_begin()->type;
446 llvm::Value *Arg =
447 CGF.Builder.CreateBitCast(Addr, CGF.ConvertType(ArgTy));
448
449 CallArgList Args;
Eli Friedman04c9a492011-05-02 17:57:46 +0000450 Args.add(RValue::get(Arg),
451 CGF.getContext().getPointerType(Var.getType()));
John McCalld8715092010-07-21 06:13:08 +0000452 CGF.EmitCall(FnInfo, CleanupFn, ReturnValueSlot(), Args);
453 }
454 };
Nadav Rotem495cfa42013-03-23 06:43:35 +0000455
456 /// A cleanup to call @llvm.lifetime.end.
457 class CallLifetimeEnd : public EHScopeStack::Cleanup {
458 llvm::Value *Addr;
459 llvm::Value *Size;
460 public:
461 CallLifetimeEnd(llvm::Value *addr, llvm::Value *size)
462 : Addr(addr), Size(size) {}
463
464 void Emit(CodeGenFunction &CGF, Flags flags) {
465 llvm::Value *castAddr = CGF.Builder.CreateBitCast(Addr, CGF.Int8PtrTy);
466 CGF.Builder.CreateCall2(CGF.CGM.getLLVMLifetimeEndFn(),
467 Size, castAddr)
468 ->setDoesNotThrow();
469 }
470 };
John McCalld8715092010-07-21 06:13:08 +0000471}
472
John McCallf85e1932011-06-15 23:02:42 +0000473/// EmitAutoVarWithLifetime - Does the setup required for an automatic
474/// variable with lifetime.
475static void EmitAutoVarWithLifetime(CodeGenFunction &CGF, const VarDecl &var,
476 llvm::Value *addr,
477 Qualifiers::ObjCLifetime lifetime) {
478 switch (lifetime) {
479 case Qualifiers::OCL_None:
480 llvm_unreachable("present but none");
481
482 case Qualifiers::OCL_ExplicitNone:
483 // nothing to do
484 break;
485
486 case Qualifiers::OCL_Strong: {
Peter Collingbourne516bbd42012-01-26 03:33:36 +0000487 CodeGenFunction::Destroyer *destroyer =
John McCall9928c482011-07-12 16:41:08 +0000488 (var.hasAttr<ObjCPreciseLifetimeAttr>()
489 ? CodeGenFunction::destroyARCStrongPrecise
490 : CodeGenFunction::destroyARCStrongImprecise);
491
492 CleanupKind cleanupKind = CGF.getARCCleanupKind();
493 CGF.pushDestroy(cleanupKind, addr, var.getType(), destroyer,
494 cleanupKind & EHCleanup);
John McCallf85e1932011-06-15 23:02:42 +0000495 break;
496 }
497 case Qualifiers::OCL_Autoreleasing:
498 // nothing to do
499 break;
Eric Christophere1f54902011-08-23 22:38:00 +0000500
John McCallf85e1932011-06-15 23:02:42 +0000501 case Qualifiers::OCL_Weak:
502 // __weak objects always get EH cleanups; otherwise, exceptions
503 // could cause really nasty crashes instead of mere leaks.
John McCall9928c482011-07-12 16:41:08 +0000504 CGF.pushDestroy(NormalAndEHCleanup, addr, var.getType(),
505 CodeGenFunction::destroyARCWeak,
506 /*useEHCleanup*/ true);
John McCallf85e1932011-06-15 23:02:42 +0000507 break;
508 }
509}
510
511static bool isAccessedBy(const VarDecl &var, const Stmt *s) {
512 if (const Expr *e = dyn_cast<Expr>(s)) {
513 // Skip the most common kinds of expressions that make
514 // hierarchy-walking expensive.
515 s = e = e->IgnoreParenCasts();
516
517 if (const DeclRefExpr *ref = dyn_cast<DeclRefExpr>(e))
518 return (ref->getDecl() == &var);
Fariborz Jahanianddfc8a12012-06-19 20:53:26 +0000519 if (const BlockExpr *be = dyn_cast<BlockExpr>(e)) {
520 const BlockDecl *block = be->getBlockDecl();
521 for (BlockDecl::capture_const_iterator i = block->capture_begin(),
522 e = block->capture_end(); i != e; ++i) {
523 if (i->getVariable() == &var)
524 return true;
525 }
526 }
John McCallf85e1932011-06-15 23:02:42 +0000527 }
528
529 for (Stmt::const_child_range children = s->children(); children; ++children)
Fariborz Jahanian8fefc8e2011-06-29 20:00:16 +0000530 // children might be null; as in missing decl or conditional of an if-stmt.
531 if ((*children) && isAccessedBy(var, *children))
John McCallf85e1932011-06-15 23:02:42 +0000532 return true;
533
534 return false;
535}
536
537static bool isAccessedBy(const ValueDecl *decl, const Expr *e) {
538 if (!decl) return false;
539 if (!isa<VarDecl>(decl)) return false;
540 const VarDecl *var = cast<VarDecl>(decl);
541 return isAccessedBy(*var, e);
542}
543
John McCalla07398e2011-06-16 04:16:24 +0000544static void drillIntoBlockVariable(CodeGenFunction &CGF,
545 LValue &lvalue,
546 const VarDecl *var) {
547 lvalue.setAddress(CGF.BuildBlockByrefAddress(lvalue.getAddress(), var));
548}
549
John McCallf85e1932011-06-15 23:02:42 +0000550void CodeGenFunction::EmitScalarInit(const Expr *init,
551 const ValueDecl *D,
John McCalla07398e2011-06-16 04:16:24 +0000552 LValue lvalue,
553 bool capturedByInit) {
John McCalla07398e2011-06-16 04:16:24 +0000554 Qualifiers::ObjCLifetime lifetime = lvalue.getObjCLifetime();
John McCallf85e1932011-06-15 23:02:42 +0000555 if (!lifetime) {
556 llvm::Value *value = EmitScalarExpr(init);
John McCalla07398e2011-06-16 04:16:24 +0000557 if (capturedByInit)
558 drillIntoBlockVariable(*this, lvalue, cast<VarDecl>(D));
David Chisnall7a7ee302012-01-16 17:27:18 +0000559 EmitStoreThroughLValue(RValue::get(value), lvalue, true);
John McCallf85e1932011-06-15 23:02:42 +0000560 return;
561 }
562
563 // If we're emitting a value with lifetime, we have to do the
564 // initialization *before* we leave the cleanup scopes.
John McCall1a343eb2011-11-10 08:15:53 +0000565 if (const ExprWithCleanups *ewc = dyn_cast<ExprWithCleanups>(init)) {
566 enterFullExpression(ewc);
John McCallf85e1932011-06-15 23:02:42 +0000567 init = ewc->getSubExpr();
John McCall1a343eb2011-11-10 08:15:53 +0000568 }
569 CodeGenFunction::RunCleanupsScope Scope(*this);
John McCallf85e1932011-06-15 23:02:42 +0000570
571 // We have to maintain the illusion that the variable is
572 // zero-initialized. If the variable might be accessed in its
573 // initializer, zero-initialize before running the initializer, then
574 // actually perform the initialization with an assign.
575 bool accessedByInit = false;
576 if (lifetime != Qualifiers::OCL_ExplicitNone)
John McCallfb720812011-07-28 07:23:35 +0000577 accessedByInit = (capturedByInit || isAccessedBy(D, init));
John McCallf85e1932011-06-15 23:02:42 +0000578 if (accessedByInit) {
John McCalla07398e2011-06-16 04:16:24 +0000579 LValue tempLV = lvalue;
John McCallf85e1932011-06-15 23:02:42 +0000580 // Drill down to the __block object if necessary.
John McCallf85e1932011-06-15 23:02:42 +0000581 if (capturedByInit) {
582 // We can use a simple GEP for this because it can't have been
583 // moved yet.
John McCalla07398e2011-06-16 04:16:24 +0000584 tempLV.setAddress(Builder.CreateStructGEP(tempLV.getAddress(),
585 getByRefValueLLVMField(cast<VarDecl>(D))));
John McCallf85e1932011-06-15 23:02:42 +0000586 }
587
Chris Lattner2acc6e32011-07-18 04:24:23 +0000588 llvm::PointerType *ty
John McCalla07398e2011-06-16 04:16:24 +0000589 = cast<llvm::PointerType>(tempLV.getAddress()->getType());
John McCallf85e1932011-06-15 23:02:42 +0000590 ty = cast<llvm::PointerType>(ty->getElementType());
591
592 llvm::Value *zero = llvm::ConstantPointerNull::get(ty);
Eric Christophere1f54902011-08-23 22:38:00 +0000593
John McCallf85e1932011-06-15 23:02:42 +0000594 // If __weak, we want to use a barrier under certain conditions.
595 if (lifetime == Qualifiers::OCL_Weak)
John McCalla07398e2011-06-16 04:16:24 +0000596 EmitARCInitWeak(tempLV.getAddress(), zero);
John McCallf85e1932011-06-15 23:02:42 +0000597
598 // Otherwise just do a simple store.
599 else
David Chisnall7a7ee302012-01-16 17:27:18 +0000600 EmitStoreOfScalar(zero, tempLV, /* isInitialization */ true);
John McCallf85e1932011-06-15 23:02:42 +0000601 }
602
603 // Emit the initializer.
604 llvm::Value *value = 0;
605
606 switch (lifetime) {
607 case Qualifiers::OCL_None:
608 llvm_unreachable("present but none");
609
610 case Qualifiers::OCL_ExplicitNone:
611 // nothing to do
612 value = EmitScalarExpr(init);
613 break;
614
615 case Qualifiers::OCL_Strong: {
616 value = EmitARCRetainScalarExpr(init);
617 break;
618 }
619
620 case Qualifiers::OCL_Weak: {
621 // No way to optimize a producing initializer into this. It's not
622 // worth optimizing for, because the value will immediately
623 // disappear in the common case.
624 value = EmitScalarExpr(init);
625
John McCalla07398e2011-06-16 04:16:24 +0000626 if (capturedByInit) drillIntoBlockVariable(*this, lvalue, cast<VarDecl>(D));
John McCallf85e1932011-06-15 23:02:42 +0000627 if (accessedByInit)
John McCalla07398e2011-06-16 04:16:24 +0000628 EmitARCStoreWeak(lvalue.getAddress(), value, /*ignored*/ true);
John McCallf85e1932011-06-15 23:02:42 +0000629 else
John McCalla07398e2011-06-16 04:16:24 +0000630 EmitARCInitWeak(lvalue.getAddress(), value);
John McCallf85e1932011-06-15 23:02:42 +0000631 return;
632 }
633
634 case Qualifiers::OCL_Autoreleasing:
635 value = EmitARCRetainAutoreleaseScalarExpr(init);
636 break;
637 }
638
John McCalla07398e2011-06-16 04:16:24 +0000639 if (capturedByInit) drillIntoBlockVariable(*this, lvalue, cast<VarDecl>(D));
John McCallf85e1932011-06-15 23:02:42 +0000640
641 // If the variable might have been accessed by its initializer, we
642 // might have to initialize with a barrier. We have to do this for
643 // both __weak and __strong, but __weak got filtered out above.
644 if (accessedByInit && lifetime == Qualifiers::OCL_Strong) {
John McCalla07398e2011-06-16 04:16:24 +0000645 llvm::Value *oldValue = EmitLoadOfScalar(lvalue);
David Chisnall7a7ee302012-01-16 17:27:18 +0000646 EmitStoreOfScalar(value, lvalue, /* isInitialization */ true);
John McCall5b07e802013-03-13 03:10:54 +0000647 EmitARCRelease(oldValue, ARCImpreciseLifetime);
John McCallf85e1932011-06-15 23:02:42 +0000648 return;
649 }
650
David Chisnall7a7ee302012-01-16 17:27:18 +0000651 EmitStoreOfScalar(value, lvalue, /* isInitialization */ true);
John McCallf85e1932011-06-15 23:02:42 +0000652}
Chris Lattner94cd0112010-12-01 02:05:19 +0000653
John McCall7acddac2011-06-17 06:42:21 +0000654/// EmitScalarInit - Initialize the given lvalue with the given object.
655void CodeGenFunction::EmitScalarInit(llvm::Value *init, LValue lvalue) {
656 Qualifiers::ObjCLifetime lifetime = lvalue.getObjCLifetime();
657 if (!lifetime)
David Chisnall7a7ee302012-01-16 17:27:18 +0000658 return EmitStoreThroughLValue(RValue::get(init), lvalue, true);
John McCall7acddac2011-06-17 06:42:21 +0000659
660 switch (lifetime) {
661 case Qualifiers::OCL_None:
662 llvm_unreachable("present but none");
663
664 case Qualifiers::OCL_ExplicitNone:
665 // nothing to do
666 break;
667
668 case Qualifiers::OCL_Strong:
669 init = EmitARCRetain(lvalue.getType(), init);
670 break;
671
672 case Qualifiers::OCL_Weak:
673 // Initialize and then skip the primitive store.
674 EmitARCInitWeak(lvalue.getAddress(), init);
675 return;
676
677 case Qualifiers::OCL_Autoreleasing:
678 init = EmitARCRetainAutorelease(lvalue.getType(), init);
679 break;
680 }
681
David Chisnall7a7ee302012-01-16 17:27:18 +0000682 EmitStoreOfScalar(init, lvalue, /* isInitialization */ true);
John McCall7acddac2011-06-17 06:42:21 +0000683}
684
Chris Lattner94cd0112010-12-01 02:05:19 +0000685/// canEmitInitWithFewStoresAfterMemset - Decide whether we can emit the
686/// non-zero parts of the specified initializer with equal or fewer than
687/// NumStores scalar stores.
688static bool canEmitInitWithFewStoresAfterMemset(llvm::Constant *Init,
689 unsigned &NumStores) {
Chris Lattner70b02942010-12-02 01:58:41 +0000690 // Zero and Undef never requires any extra stores.
691 if (isa<llvm::ConstantAggregateZero>(Init) ||
692 isa<llvm::ConstantPointerNull>(Init) ||
693 isa<llvm::UndefValue>(Init))
694 return true;
695 if (isa<llvm::ConstantInt>(Init) || isa<llvm::ConstantFP>(Init) ||
696 isa<llvm::ConstantVector>(Init) || isa<llvm::BlockAddress>(Init) ||
697 isa<llvm::ConstantExpr>(Init))
698 return Init->isNullValue() || NumStores--;
699
700 // See if we can emit each element.
701 if (isa<llvm::ConstantArray>(Init) || isa<llvm::ConstantStruct>(Init)) {
702 for (unsigned i = 0, e = Init->getNumOperands(); i != e; ++i) {
703 llvm::Constant *Elt = cast<llvm::Constant>(Init->getOperand(i));
704 if (!canEmitInitWithFewStoresAfterMemset(Elt, NumStores))
705 return false;
706 }
707 return true;
708 }
Chris Lattnerf492cb12012-01-31 04:36:19 +0000709
710 if (llvm::ConstantDataSequential *CDS =
711 dyn_cast<llvm::ConstantDataSequential>(Init)) {
712 for (unsigned i = 0, e = CDS->getNumElements(); i != e; ++i) {
713 llvm::Constant *Elt = CDS->getElementAsConstant(i);
714 if (!canEmitInitWithFewStoresAfterMemset(Elt, NumStores))
715 return false;
716 }
717 return true;
718 }
Eric Christophere1f54902011-08-23 22:38:00 +0000719
Chris Lattner94cd0112010-12-01 02:05:19 +0000720 // Anything else is hard and scary.
721 return false;
722}
723
724/// emitStoresForInitAfterMemset - For inits that
725/// canEmitInitWithFewStoresAfterMemset returned true for, emit the scalar
726/// stores that would be required.
727static void emitStoresForInitAfterMemset(llvm::Constant *Init, llvm::Value *Loc,
John McCall34695852011-02-22 06:44:22 +0000728 bool isVolatile, CGBuilderTy &Builder) {
Benjamin Kramer06d43682012-08-27 22:07:02 +0000729 assert(!Init->isNullValue() && !isa<llvm::UndefValue>(Init) &&
730 "called emitStoresForInitAfterMemset for zero or undef value.");
Eric Christophere1f54902011-08-23 22:38:00 +0000731
Chris Lattner70b02942010-12-02 01:58:41 +0000732 if (isa<llvm::ConstantInt>(Init) || isa<llvm::ConstantFP>(Init) ||
733 isa<llvm::ConstantVector>(Init) || isa<llvm::BlockAddress>(Init) ||
734 isa<llvm::ConstantExpr>(Init)) {
Chris Lattnerf492cb12012-01-31 04:36:19 +0000735 Builder.CreateStore(Init, Loc, isVolatile);
736 return;
737 }
738
739 if (llvm::ConstantDataSequential *CDS =
740 dyn_cast<llvm::ConstantDataSequential>(Init)) {
741 for (unsigned i = 0, e = CDS->getNumElements(); i != e; ++i) {
742 llvm::Constant *Elt = CDS->getElementAsConstant(i);
Benjamin Kramercfa07e32012-08-27 21:35:58 +0000743
744 // If necessary, get a pointer to the element and emit it.
745 if (!Elt->isNullValue() && !isa<llvm::UndefValue>(Elt))
746 emitStoresForInitAfterMemset(Elt, Builder.CreateConstGEP2_32(Loc, 0, i),
747 isVolatile, Builder);
Chris Lattnerf492cb12012-01-31 04:36:19 +0000748 }
Chris Lattner70b02942010-12-02 01:58:41 +0000749 return;
750 }
Eric Christophere1f54902011-08-23 22:38:00 +0000751
Chris Lattner70b02942010-12-02 01:58:41 +0000752 assert((isa<llvm::ConstantStruct>(Init) || isa<llvm::ConstantArray>(Init)) &&
753 "Unknown value type!");
Eric Christophere1f54902011-08-23 22:38:00 +0000754
Chris Lattner70b02942010-12-02 01:58:41 +0000755 for (unsigned i = 0, e = Init->getNumOperands(); i != e; ++i) {
756 llvm::Constant *Elt = cast<llvm::Constant>(Init->getOperand(i));
Benjamin Kramercfa07e32012-08-27 21:35:58 +0000757
758 // If necessary, get a pointer to the element and emit it.
759 if (!Elt->isNullValue() && !isa<llvm::UndefValue>(Elt))
760 emitStoresForInitAfterMemset(Elt, Builder.CreateConstGEP2_32(Loc, 0, i),
761 isVolatile, Builder);
Chris Lattner70b02942010-12-02 01:58:41 +0000762 }
Chris Lattner94cd0112010-12-01 02:05:19 +0000763}
764
765
766/// shouldUseMemSetPlusStoresToInitialize - Decide whether we should use memset
767/// plus some stores to initialize a local variable instead of using a memcpy
768/// from a constant global. It is beneficial to use memset if the global is all
769/// zeros, or mostly zeros and large.
770static bool shouldUseMemSetPlusStoresToInitialize(llvm::Constant *Init,
771 uint64_t GlobalSize) {
772 // If a global is all zeros, always use a memset.
773 if (isa<llvm::ConstantAggregateZero>(Init)) return true;
774
Chris Lattner94cd0112010-12-01 02:05:19 +0000775 // If a non-zero global is <= 32 bytes, always use a memcpy. If it is large,
776 // do it if it will require 6 or fewer scalar stores.
777 // TODO: Should budget depends on the size? Avoiding a large global warrants
778 // plopping in more stores.
779 unsigned StoreBudget = 6;
780 uint64_t SizeLimit = 32;
Eric Christophere1f54902011-08-23 22:38:00 +0000781
782 return GlobalSize > SizeLimit &&
Chris Lattner94cd0112010-12-01 02:05:19 +0000783 canEmitInitWithFewStoresAfterMemset(Init, StoreBudget);
784}
785
Nadav Rotem495cfa42013-03-23 06:43:35 +0000786/// Should we use the LLVM lifetime intrinsics for the given local variable?
787static bool shouldUseLifetimeMarkers(CodeGenFunction &CGF, const VarDecl &D,
788 unsigned Size) {
789 // For now, only in optimized builds.
790 if (CGF.CGM.getCodeGenOpts().OptimizationLevel == 0)
791 return false;
792
793 // Limit the size of marked objects to 32 bytes. We don't want to increase
794 // compile time by marking tiny objects.
795 unsigned SizeThreshold = 32;
796
797 return Size > SizeThreshold;
798}
799
Chris Lattner94cd0112010-12-01 02:05:19 +0000800
Nick Lewyckya9de3fa2010-12-30 20:21:55 +0000801/// EmitAutoVarDecl - Emit code and set up an entry in LocalDeclMap for a
Reid Spencer5f016e22007-07-11 17:01:13 +0000802/// variable declaration with auto, register, or no storage class specifier.
Chris Lattner2621fd12008-05-08 05:58:21 +0000803/// These turn into simple stack objects, or GlobalValues depending on target.
John McCall34695852011-02-22 06:44:22 +0000804void CodeGenFunction::EmitAutoVarDecl(const VarDecl &D) {
805 AutoVarEmission emission = EmitAutoVarAlloca(D);
806 EmitAutoVarInit(emission);
807 EmitAutoVarCleanups(emission);
808}
Reid Spencer5f016e22007-07-11 17:01:13 +0000809
John McCall34695852011-02-22 06:44:22 +0000810/// EmitAutoVarAlloca - Emit the alloca and debug information for a
811/// local variable. Does not emit initalization or destruction.
812CodeGenFunction::AutoVarEmission
813CodeGenFunction::EmitAutoVarAlloca(const VarDecl &D) {
814 QualType Ty = D.getType();
815
816 AutoVarEmission emission(D);
817
818 bool isByRef = D.hasAttr<BlocksAttr>();
819 emission.IsByRef = isByRef;
820
821 CharUnits alignment = getContext().getDeclAlign(&D);
822 emission.Alignment = alignment;
823
John McCallbc8d40d2011-06-24 21:55:10 +0000824 // If the type is variably-modified, emit all the VLA sizes for it.
825 if (Ty->isVariablyModifiedType())
826 EmitVariablyModifiedType(Ty);
827
Reid Spencer5f016e22007-07-11 17:01:13 +0000828 llvm::Value *DeclPtr;
Eli Friedman3c2b3172008-02-15 12:20:59 +0000829 if (Ty->isConstantSizeType()) {
Chris Lattner2621fd12008-05-08 05:58:21 +0000830 if (!Target.useGlobalsForAutomaticVariables()) {
Richard Smith7edf9e32012-11-01 22:30:59 +0000831 bool NRVO = getLangOpts().ElideConstructors &&
John McCall34695852011-02-22 06:44:22 +0000832 D.isNRVOVariable();
833
834 // If this value is a POD array or struct with a statically
Richard Smith4bb66862011-12-02 00:30:33 +0000835 // determinable constant initializer, there are optimizations we can do.
836 //
Richard Smitha9b21d22012-02-17 06:48:11 +0000837 // TODO: We should constant-evaluate the initializer of any variable,
Richard Smith4bb66862011-12-02 00:30:33 +0000838 // as long as it is initialized by a constant expression. Currently,
839 // isConstantInitializer produces wrong answers for structs with
840 // reference or bitfield members, and a few other cases, and checking
841 // for POD-ness protects us from some of these.
John McCall34695852011-02-22 06:44:22 +0000842 if (D.getInit() &&
Eric Christophere1f54902011-08-23 22:38:00 +0000843 (Ty->isArrayType() || Ty->isRecordType()) &&
John McCallf85e1932011-06-15 23:02:42 +0000844 (Ty.isPODType(getContext()) ||
845 getContext().getBaseElementType(Ty)->isObjCObjectPointerType()) &&
John McCall4204f072010-08-02 21:13:48 +0000846 D.getInit()->isConstantInitializer(getContext(), false)) {
John McCall34695852011-02-22 06:44:22 +0000847
848 // If the variable's a const type, and it's neither an NRVO
Richard Smith4bb66862011-12-02 00:30:33 +0000849 // candidate nor a __block variable and has no mutable members,
850 // emit it as a global instead.
Richard Smitha9b21d22012-02-17 06:48:11 +0000851 if (CGM.getCodeGenOpts().MergeAllConstants && !NRVO && !isByRef &&
852 CGM.isTypeConstant(Ty, true)) {
853 EmitStaticVarDecl(D, llvm::GlobalValue::InternalLinkage);
John McCall34695852011-02-22 06:44:22 +0000854
Richard Smitha9b21d22012-02-17 06:48:11 +0000855 emission.Address = 0; // signal this condition to later callbacks
856 assert(emission.wasEmittedAsGlobal());
857 return emission;
Tanya Lattner59876c22009-11-04 01:18:09 +0000858 }
John McCall34695852011-02-22 06:44:22 +0000859
860 // Otherwise, tell the initialization code that we're in this case.
861 emission.IsConstantAggregate = true;
Tanya Lattner59876c22009-11-04 01:18:09 +0000862 }
Eric Christophere1f54902011-08-23 22:38:00 +0000863
Douglas Gregord86c4772010-05-15 06:46:45 +0000864 // A normal fixed sized variable becomes an alloca in the entry block,
865 // unless it's an NRVO variable.
Chris Lattner2acc6e32011-07-18 04:24:23 +0000866 llvm::Type *LTy = ConvertTypeForMem(Ty);
Eric Christophere1f54902011-08-23 22:38:00 +0000867
Douglas Gregord86c4772010-05-15 06:46:45 +0000868 if (NRVO) {
869 // The named return value optimization: allocate this variable in the
870 // return slot, so that we can elide the copy when returning this
871 // variable (C++0x [class.copy]p34).
872 DeclPtr = ReturnValue;
Eric Christophere1f54902011-08-23 22:38:00 +0000873
Douglas Gregor3d91bbc2010-05-17 15:52:46 +0000874 if (const RecordType *RecordTy = Ty->getAs<RecordType>()) {
875 if (!cast<CXXRecordDecl>(RecordTy->getDecl())->hasTrivialDestructor()) {
876 // Create a flag that is used to indicate when the NRVO was applied
Eric Christophere1f54902011-08-23 22:38:00 +0000877 // to this variable. Set it to zero to indicate that NRVO was not
Douglas Gregor3d91bbc2010-05-17 15:52:46 +0000878 // applied.
Chris Lattner4c53dc12010-12-01 01:47:15 +0000879 llvm::Value *Zero = Builder.getFalse();
John McCall34695852011-02-22 06:44:22 +0000880 llvm::Value *NRVOFlag = CreateTempAlloca(Zero->getType(), "nrvo");
Nick Lewyckya03733b2011-02-16 23:59:08 +0000881 EnsureInsertPoint();
Douglas Gregor3d91bbc2010-05-17 15:52:46 +0000882 Builder.CreateStore(Zero, NRVOFlag);
Eric Christophere1f54902011-08-23 22:38:00 +0000883
Douglas Gregor3d91bbc2010-05-17 15:52:46 +0000884 // Record the NRVO flag for this variable.
885 NRVOFlags[&D] = NRVOFlag;
John McCall34695852011-02-22 06:44:22 +0000886 emission.NRVOFlag = NRVOFlag;
Douglas Gregor3d91bbc2010-05-17 15:52:46 +0000887 }
888 }
Douglas Gregord86c4772010-05-15 06:46:45 +0000889 } else {
890 if (isByRef)
891 LTy = BuildByRefType(&D);
Eric Christophere1f54902011-08-23 22:38:00 +0000892
Douglas Gregord86c4772010-05-15 06:46:45 +0000893 llvm::AllocaInst *Alloc = CreateTempAlloca(LTy);
Benjamin Kramer7a715242011-11-29 14:46:55 +0000894 Alloc->setName(D.getName());
Mike Stump1eb44332009-09-09 15:08:12 +0000895
John McCall34695852011-02-22 06:44:22 +0000896 CharUnits allocaAlignment = alignment;
Douglas Gregord86c4772010-05-15 06:46:45 +0000897 if (isByRef)
Eric Christophere1f54902011-08-23 22:38:00 +0000898 allocaAlignment = std::max(allocaAlignment,
Ken Dyck06f486e2011-01-18 02:01:14 +0000899 getContext().toCharUnitsFromBits(Target.getPointerAlign(0)));
John McCall34695852011-02-22 06:44:22 +0000900 Alloc->setAlignment(allocaAlignment.getQuantity());
Douglas Gregord86c4772010-05-15 06:46:45 +0000901 DeclPtr = Alloc;
Nadav Rotem495cfa42013-03-23 06:43:35 +0000902
903 // Emit a lifetime intrinsic if meaningful. There's no point
904 // in doing this if we don't have a valid insertion point (?).
905 uint64_t size = CGM.getDataLayout().getTypeAllocSize(LTy);
906 if (HaveInsertPoint() && shouldUseLifetimeMarkers(*this, D, size)) {
907 llvm::Value *sizeV = llvm::ConstantInt::get(Int64Ty, size);
908
909 emission.SizeForLifetimeMarkers = sizeV;
910 llvm::Value *castAddr = Builder.CreateBitCast(Alloc, Int8PtrTy);
911 Builder.CreateCall2(CGM.getLLVMLifetimeStartFn(), sizeV, castAddr)
912 ->setDoesNotThrow();
913 } else {
914 assert(!emission.useLifetimeMarkers());
915 }
Douglas Gregord86c4772010-05-15 06:46:45 +0000916 }
Chris Lattner2621fd12008-05-08 05:58:21 +0000917 } else {
918 // Targets that don't support recursion emit locals as globals.
919 const char *Class =
John McCalld931b082010-08-26 03:08:43 +0000920 D.getStorageClass() == SC_Register ? ".reg." : ".auto.";
John McCallb6bbcc92010-10-15 04:57:14 +0000921 DeclPtr = CreateStaticVarDecl(D, Class,
922 llvm::GlobalValue::InternalLinkage);
Chris Lattner2621fd12008-05-08 05:58:21 +0000923 }
Reid Spencer5f016e22007-07-11 17:01:13 +0000924 } else {
Daniel Dunbard286f052009-07-19 06:58:07 +0000925 EnsureInsertPoint();
926
Anders Carlsson5ecb1b92009-02-09 20:41:50 +0000927 if (!DidCallStackSave) {
Anders Carlsson5d463152008-12-12 07:38:43 +0000928 // Save the stack.
John McCalld16c2cf2011-02-08 08:22:06 +0000929 llvm::Value *Stack = CreateTempAlloca(Int8PtrTy, "saved_stack");
Mike Stump1eb44332009-09-09 15:08:12 +0000930
Anders Carlsson5d463152008-12-12 07:38:43 +0000931 llvm::Value *F = CGM.getIntrinsic(llvm::Intrinsic::stacksave);
932 llvm::Value *V = Builder.CreateCall(F);
Mike Stump1eb44332009-09-09 15:08:12 +0000933
Anders Carlsson5d463152008-12-12 07:38:43 +0000934 Builder.CreateStore(V, Stack);
Anders Carlsson5ecb1b92009-02-09 20:41:50 +0000935
936 DidCallStackSave = true;
Mike Stump1eb44332009-09-09 15:08:12 +0000937
John McCalld8715092010-07-21 06:13:08 +0000938 // Push a cleanup block and restore the stack there.
John McCall3ad32c82011-01-28 08:37:24 +0000939 // FIXME: in general circumstances, this should be an EH cleanup.
John McCall1f0fca52010-07-21 07:22:38 +0000940 EHStack.pushCleanup<CallStackRestore>(NormalCleanup, Stack);
Anders Carlsson5d463152008-12-12 07:38:43 +0000941 }
Mike Stump1eb44332009-09-09 15:08:12 +0000942
John McCallbc8d40d2011-06-24 21:55:10 +0000943 llvm::Value *elementCount;
944 QualType elementType;
945 llvm::tie(elementCount, elementType) = getVLASize(Ty);
Anders Carlsson5d463152008-12-12 07:38:43 +0000946
Chris Lattner2acc6e32011-07-18 04:24:23 +0000947 llvm::Type *llvmTy = ConvertTypeForMem(elementType);
Anders Carlsson5d463152008-12-12 07:38:43 +0000948
949 // Allocate memory for the array.
John McCallbc8d40d2011-06-24 21:55:10 +0000950 llvm::AllocaInst *vla = Builder.CreateAlloca(llvmTy, elementCount, "vla");
951 vla->setAlignment(alignment.getQuantity());
Anders Carlsson41f8a132009-09-26 18:16:06 +0000952
John McCallbc8d40d2011-06-24 21:55:10 +0000953 DeclPtr = vla;
Reid Spencer5f016e22007-07-11 17:01:13 +0000954 }
Eli Friedman8f39f5e2008-12-20 23:11:59 +0000955
Reid Spencer5f016e22007-07-11 17:01:13 +0000956 llvm::Value *&DMEntry = LocalDeclMap[&D];
957 assert(DMEntry == 0 && "Decl already exists in localdeclmap!");
958 DMEntry = DeclPtr;
John McCall34695852011-02-22 06:44:22 +0000959 emission.Address = DeclPtr;
Sanjiv Guptacc9b1632008-05-30 10:30:31 +0000960
961 // Emit debug info for local var declaration.
Devang Patelc594abd2011-06-03 19:21:47 +0000962 if (HaveInsertPoint())
963 if (CGDebugInfo *DI = getDebugInfo()) {
Douglas Gregor4cdad312012-10-23 20:05:01 +0000964 if (CGM.getCodeGenOpts().getDebugInfo()
965 >= CodeGenOptions::LimitedDebugInfo) {
Alexey Samsonovfd00eec2012-05-04 07:39:27 +0000966 DI->setLocation(D.getLocation());
967 if (Target.useGlobalsForAutomaticVariables()) {
968 DI->EmitGlobalVariable(static_cast<llvm::GlobalVariable *>(DeclPtr),
969 &D);
970 } else
971 DI->EmitDeclareOfAutoVariable(&D, DeclPtr, Builder);
972 }
Devang Patelc594abd2011-06-03 19:21:47 +0000973 }
Sanjiv Guptacc9b1632008-05-30 10:30:31 +0000974
Julien Lerouge77f68bb2011-09-09 22:41:49 +0000975 if (D.hasAttr<AnnotateAttr>())
976 EmitVarAnnotations(&D, emission.Address);
977
John McCall34695852011-02-22 06:44:22 +0000978 return emission;
979}
980
981/// Determines whether the given __block variable is potentially
982/// captured by the given expression.
983static bool isCapturedBy(const VarDecl &var, const Expr *e) {
984 // Skip the most common kinds of expressions that make
985 // hierarchy-walking expensive.
986 e = e->IgnoreParenCasts();
987
988 if (const BlockExpr *be = dyn_cast<BlockExpr>(e)) {
989 const BlockDecl *block = be->getBlockDecl();
990 for (BlockDecl::capture_const_iterator i = block->capture_begin(),
991 e = block->capture_end(); i != e; ++i) {
992 if (i->getVariable() == &var)
993 return true;
994 }
995
996 // No need to walk into the subexpressions.
997 return false;
998 }
999
Fariborz Jahanian5033be12011-08-23 16:47:15 +00001000 if (const StmtExpr *SE = dyn_cast<StmtExpr>(e)) {
1001 const CompoundStmt *CS = SE->getSubStmt();
Eric Christopherc6fad602011-08-23 23:44:09 +00001002 for (CompoundStmt::const_body_iterator BI = CS->body_begin(),
1003 BE = CS->body_end(); BI != BE; ++BI)
Fariborz Jahanian045c8422011-08-25 00:06:26 +00001004 if (Expr *E = dyn_cast<Expr>((*BI))) {
Fariborz Jahanian5033be12011-08-23 16:47:15 +00001005 if (isCapturedBy(var, E))
1006 return true;
Fariborz Jahanian045c8422011-08-25 00:06:26 +00001007 }
1008 else if (DeclStmt *DS = dyn_cast<DeclStmt>((*BI))) {
1009 // special case declarations
1010 for (DeclStmt::decl_iterator I = DS->decl_begin(), E = DS->decl_end();
1011 I != E; ++I) {
1012 if (VarDecl *VD = dyn_cast<VarDecl>((*I))) {
1013 Expr *Init = VD->getInit();
1014 if (Init && isCapturedBy(var, Init))
1015 return true;
1016 }
1017 }
1018 }
1019 else
1020 // FIXME. Make safe assumption assuming arbitrary statements cause capturing.
1021 // Later, provide code to poke into statements for capture analysis.
1022 return true;
Fariborz Jahanian5033be12011-08-23 16:47:15 +00001023 return false;
1024 }
Eric Christophere1f54902011-08-23 22:38:00 +00001025
John McCall34695852011-02-22 06:44:22 +00001026 for (Stmt::const_child_range children = e->children(); children; ++children)
1027 if (isCapturedBy(var, cast<Expr>(*children)))
1028 return true;
1029
1030 return false;
1031}
1032
Douglas Gregorbcc3e662011-07-01 21:08:19 +00001033/// \brief Determine whether the given initializer is trivial in the sense
1034/// that it requires no code to be generated.
1035static bool isTrivialInitializer(const Expr *Init) {
1036 if (!Init)
1037 return true;
Eric Christophere1f54902011-08-23 22:38:00 +00001038
Douglas Gregorbcc3e662011-07-01 21:08:19 +00001039 if (const CXXConstructExpr *Construct = dyn_cast<CXXConstructExpr>(Init))
1040 if (CXXConstructorDecl *Constructor = Construct->getConstructor())
1041 if (Constructor->isTrivial() &&
1042 Constructor->isDefaultConstructor() &&
1043 !Construct->requiresZeroInitialization())
1044 return true;
Eric Christophere1f54902011-08-23 22:38:00 +00001045
Douglas Gregorbcc3e662011-07-01 21:08:19 +00001046 return false;
1047}
John McCall34695852011-02-22 06:44:22 +00001048void CodeGenFunction::EmitAutoVarInit(const AutoVarEmission &emission) {
John McCall57b3b6a2011-02-22 07:16:58 +00001049 assert(emission.Variable && "emission was not valid!");
1050
John McCall34695852011-02-22 06:44:22 +00001051 // If this was emitted as a global constant, we're done.
1052 if (emission.wasEmittedAsGlobal()) return;
1053
John McCall57b3b6a2011-02-22 07:16:58 +00001054 const VarDecl &D = *emission.Variable;
John McCall34695852011-02-22 06:44:22 +00001055 QualType type = D.getType();
1056
Chris Lattner19785962007-07-12 00:39:48 +00001057 // If this local has an initializer, emit it now.
Daniel Dunbard286f052009-07-19 06:58:07 +00001058 const Expr *Init = D.getInit();
1059
1060 // If we are at an unreachable point, we don't need to emit the initializer
1061 // unless it contains a label.
1062 if (!HaveInsertPoint()) {
John McCall34695852011-02-22 06:44:22 +00001063 if (!Init || !ContainsLabel(Init)) return;
1064 EnsureInsertPoint();
Daniel Dunbard286f052009-07-19 06:58:07 +00001065 }
1066
John McCall5af02db2011-03-31 01:59:53 +00001067 // Initialize the structure of a __block variable.
1068 if (emission.IsByRef)
1069 emitByrefStructureInit(emission);
Anders Carlsson69c68b72009-02-07 23:51:38 +00001070
Douglas Gregorbcc3e662011-07-01 21:08:19 +00001071 if (isTrivialInitializer(Init))
1072 return;
Eric Christophere1f54902011-08-23 22:38:00 +00001073
John McCall5af02db2011-03-31 01:59:53 +00001074 CharUnits alignment = emission.Alignment;
1075
John McCall34695852011-02-22 06:44:22 +00001076 // Check whether this is a byref variable that's potentially
1077 // captured and moved by its own initializer. If so, we'll need to
1078 // emit the initializer first, then copy into the variable.
1079 bool capturedByInit = emission.IsByRef && isCapturedBy(D, Init);
1080
1081 llvm::Value *Loc =
1082 capturedByInit ? emission.Address : emission.getObjectAddress(*this);
1083
Richard Smith51201882011-12-30 21:15:51 +00001084 llvm::Constant *constant = 0;
1085 if (emission.IsConstantAggregate) {
1086 assert(!capturedByInit && "constant init contains a capturing block?");
Richard Smith2d6a5672012-01-14 04:30:29 +00001087 constant = CGM.EmitConstantInit(D, this);
Richard Smith51201882011-12-30 21:15:51 +00001088 }
1089
1090 if (!constant) {
Eli Friedman6da2c712011-12-03 04:14:32 +00001091 LValue lv = MakeAddrLValue(Loc, type, alignment);
John McCalla07398e2011-06-16 04:16:24 +00001092 lv.setNonGC(true);
1093 return EmitExprAsInit(Init, &D, lv, capturedByInit);
1094 }
John McCall60d33652011-03-08 09:11:50 +00001095
John McCall34695852011-02-22 06:44:22 +00001096 // If this is a simple aggregate initialization, we can optimize it
1097 // in various ways.
John McCall60d33652011-03-08 09:11:50 +00001098 bool isVolatile = type.isVolatileQualified();
John McCall34695852011-02-22 06:44:22 +00001099
John McCall60d33652011-03-08 09:11:50 +00001100 llvm::Value *SizeVal =
Eric Christophere1f54902011-08-23 22:38:00 +00001101 llvm::ConstantInt::get(IntPtrTy,
John McCall60d33652011-03-08 09:11:50 +00001102 getContext().getTypeSizeInChars(type).getQuantity());
John McCall34695852011-02-22 06:44:22 +00001103
Chris Lattner2acc6e32011-07-18 04:24:23 +00001104 llvm::Type *BP = Int8PtrTy;
John McCall60d33652011-03-08 09:11:50 +00001105 if (Loc->getType() != BP)
Benjamin Kramer578faa82011-09-27 21:06:10 +00001106 Loc = Builder.CreateBitCast(Loc, BP);
Mon P Wang3ecd7852010-04-04 03:10:52 +00001107
John McCall60d33652011-03-08 09:11:50 +00001108 // If the initializer is all or mostly zeros, codegen with memset then do
1109 // a few stores afterward.
Eric Christophere1f54902011-08-23 22:38:00 +00001110 if (shouldUseMemSetPlusStoresToInitialize(constant,
Micah Villmow25a6a842012-10-08 16:25:52 +00001111 CGM.getDataLayout().getTypeAllocSize(constant->getType()))) {
John McCall60d33652011-03-08 09:11:50 +00001112 Builder.CreateMemSet(Loc, llvm::ConstantInt::get(Int8Ty, 0), SizeVal,
1113 alignment.getQuantity(), isVolatile);
Benjamin Kramer06d43682012-08-27 22:07:02 +00001114 // Zero and undef don't require a stores.
1115 if (!constant->isNullValue() && !isa<llvm::UndefValue>(constant)) {
John McCall60d33652011-03-08 09:11:50 +00001116 Loc = Builder.CreateBitCast(Loc, constant->getType()->getPointerTo());
1117 emitStoresForInitAfterMemset(constant, Loc, isVolatile, Builder);
Fariborz Jahanian20e1c7e2010-03-12 21:40:43 +00001118 }
John McCall60d33652011-03-08 09:11:50 +00001119 } else {
Eric Christophere1f54902011-08-23 22:38:00 +00001120 // Otherwise, create a temporary global with the initializer then
John McCall60d33652011-03-08 09:11:50 +00001121 // memcpy from the global to the alloca.
1122 std::string Name = GetStaticDeclName(*this, D, ".");
1123 llvm::GlobalVariable *GV =
1124 new llvm::GlobalVariable(CGM.getModule(), constant->getType(), true,
Eric Christopher736a9c22011-08-24 00:33:55 +00001125 llvm::GlobalValue::PrivateLinkage,
Hans Wennborg5e2d5de2012-06-23 11:51:46 +00001126 constant, Name);
John McCall60d33652011-03-08 09:11:50 +00001127 GV->setAlignment(alignment.getQuantity());
Eli Friedman460980d2011-05-27 22:32:55 +00001128 GV->setUnnamedAddr(true);
Eric Christophere1f54902011-08-23 22:38:00 +00001129
John McCall60d33652011-03-08 09:11:50 +00001130 llvm::Value *SrcPtr = GV;
1131 if (SrcPtr->getType() != BP)
Benjamin Kramer578faa82011-09-27 21:06:10 +00001132 SrcPtr = Builder.CreateBitCast(SrcPtr, BP);
John McCall60d33652011-03-08 09:11:50 +00001133
1134 Builder.CreateMemCpy(Loc, SrcPtr, SizeVal, alignment.getQuantity(),
1135 isVolatile);
1136 }
1137}
1138
1139/// Emit an expression as an initializer for a variable at the given
1140/// location. The expression is not necessarily the normal
1141/// initializer for the variable, and the address is not necessarily
1142/// its normal location.
1143///
1144/// \param init the initializing expression
1145/// \param var the variable to act as if we're initializing
1146/// \param loc the address to initialize; its type is a pointer
1147/// to the LLVM mapping of the variable's type
1148/// \param alignment the alignment of the address
1149/// \param capturedByInit true if the variable is a __block variable
1150/// whose address is potentially changed by the initializer
1151void CodeGenFunction::EmitExprAsInit(const Expr *init,
John McCallf85e1932011-06-15 23:02:42 +00001152 const ValueDecl *D,
John McCalla07398e2011-06-16 04:16:24 +00001153 LValue lvalue,
John McCall60d33652011-03-08 09:11:50 +00001154 bool capturedByInit) {
John McCallf85e1932011-06-15 23:02:42 +00001155 QualType type = D->getType();
John McCall60d33652011-03-08 09:11:50 +00001156
1157 if (type->isReferenceType()) {
John McCalla07398e2011-06-16 04:16:24 +00001158 RValue rvalue = EmitReferenceBindingToExpr(init, D);
Eric Christophere1f54902011-08-23 22:38:00 +00001159 if (capturedByInit)
John McCalla07398e2011-06-16 04:16:24 +00001160 drillIntoBlockVariable(*this, lvalue, cast<VarDecl>(D));
David Chisnall7a7ee302012-01-16 17:27:18 +00001161 EmitStoreThroughLValue(rvalue, lvalue, true);
John McCall9d232c82013-03-07 21:37:08 +00001162 return;
1163 }
1164 switch (getEvaluationKind(type)) {
1165 case TEK_Scalar:
John McCalla07398e2011-06-16 04:16:24 +00001166 EmitScalarInit(init, D, lvalue, capturedByInit);
John McCall9d232c82013-03-07 21:37:08 +00001167 return;
1168 case TEK_Complex: {
John McCall60d33652011-03-08 09:11:50 +00001169 ComplexPairTy complex = EmitComplexExpr(init);
John McCalla07398e2011-06-16 04:16:24 +00001170 if (capturedByInit)
1171 drillIntoBlockVariable(*this, lvalue, cast<VarDecl>(D));
John McCall9d232c82013-03-07 21:37:08 +00001172 EmitStoreOfComplex(complex, lvalue, /*init*/ true);
1173 return;
1174 }
1175 case TEK_Aggregate:
John McCall9eda3ab2013-03-07 21:37:17 +00001176 if (type->isAtomicType()) {
1177 EmitAtomicInit(const_cast<Expr*>(init), lvalue);
1178 } else {
1179 // TODO: how can we delay here if D is captured by its initializer?
1180 EmitAggExpr(init, AggValueSlot::forLValue(lvalue,
Chad Rosier649b4a12012-03-29 17:37:10 +00001181 AggValueSlot::IsDestructed,
John McCall410ffb22011-08-25 23:04:34 +00001182 AggValueSlot::DoesNotNeedGCBarriers,
Chad Rosier649b4a12012-03-29 17:37:10 +00001183 AggValueSlot::IsNotAliased));
John McCall9eda3ab2013-03-07 21:37:17 +00001184 }
Sebastian Redl972edf02012-02-19 16:03:09 +00001185 MaybeEmitStdInitializerListCleanup(lvalue.getAddress(), init);
John McCall9d232c82013-03-07 21:37:08 +00001186 return;
Fariborz Jahanian20e1c7e2010-03-12 21:40:43 +00001187 }
John McCall9d232c82013-03-07 21:37:08 +00001188 llvm_unreachable("bad evaluation kind");
John McCall34695852011-02-22 06:44:22 +00001189}
John McCallf1549f62010-07-06 01:34:17 +00001190
John McCallbdc4d802011-07-09 01:37:26 +00001191/// Enter a destroy cleanup for the given local variable.
1192void CodeGenFunction::emitAutoVarTypeCleanup(
1193 const CodeGenFunction::AutoVarEmission &emission,
1194 QualType::DestructionKind dtorKind) {
1195 assert(dtorKind != QualType::DK_none);
1196
1197 // Note that for __block variables, we want to destroy the
1198 // original stack object, not the possibly forwarded object.
1199 llvm::Value *addr = emission.getObjectAddress(*this);
1200
1201 const VarDecl *var = emission.Variable;
1202 QualType type = var->getType();
1203
1204 CleanupKind cleanupKind = NormalAndEHCleanup;
1205 CodeGenFunction::Destroyer *destroyer = 0;
1206
1207 switch (dtorKind) {
1208 case QualType::DK_none:
1209 llvm_unreachable("no cleanup for trivially-destructible variable");
1210
1211 case QualType::DK_cxx_destructor:
1212 // If there's an NRVO flag on the emission, we need a different
1213 // cleanup.
1214 if (emission.NRVOFlag) {
1215 assert(!type->isArrayType());
1216 CXXDestructorDecl *dtor = type->getAsCXXRecordDecl()->getDestructor();
1217 EHStack.pushCleanup<DestroyNRVOVariable>(cleanupKind, addr, dtor,
1218 emission.NRVOFlag);
1219 return;
1220 }
1221 break;
1222
1223 case QualType::DK_objc_strong_lifetime:
1224 // Suppress cleanups for pseudo-strong variables.
1225 if (var->isARCPseudoStrong()) return;
Eric Christophere1f54902011-08-23 22:38:00 +00001226
John McCallbdc4d802011-07-09 01:37:26 +00001227 // Otherwise, consider whether to use an EH cleanup or not.
1228 cleanupKind = getARCCleanupKind();
1229
1230 // Use the imprecise destroyer by default.
1231 if (!var->hasAttr<ObjCPreciseLifetimeAttr>())
1232 destroyer = CodeGenFunction::destroyARCStrongImprecise;
1233 break;
1234
1235 case QualType::DK_objc_weak_lifetime:
1236 break;
1237 }
1238
1239 // If we haven't chosen a more specific destroyer, use the default.
Peter Collingbourne516bbd42012-01-26 03:33:36 +00001240 if (!destroyer) destroyer = getDestroyer(dtorKind);
John McCall2673c682011-07-11 08:38:19 +00001241
Sylvestre Ledruf3477c12012-09-27 10:16:10 +00001242 // Use an EH cleanup in array destructors iff the destructor itself
John McCall2673c682011-07-11 08:38:19 +00001243 // is being pushed as an EH cleanup.
1244 bool useEHCleanup = (cleanupKind & EHCleanup);
1245 EHStack.pushCleanup<DestroyObject>(cleanupKind, addr, type, destroyer,
1246 useEHCleanup);
John McCallbdc4d802011-07-09 01:37:26 +00001247}
1248
John McCall34695852011-02-22 06:44:22 +00001249void CodeGenFunction::EmitAutoVarCleanups(const AutoVarEmission &emission) {
John McCall57b3b6a2011-02-22 07:16:58 +00001250 assert(emission.Variable && "emission was not valid!");
1251
John McCall34695852011-02-22 06:44:22 +00001252 // If this was emitted as a global constant, we're done.
1253 if (emission.wasEmittedAsGlobal()) return;
1254
John McCall38baeab2012-04-13 18:44:05 +00001255 // If we don't have an insertion point, we're done. Sema prevents
1256 // us from jumping into any of these scopes anyway.
1257 if (!HaveInsertPoint()) return;
1258
John McCall57b3b6a2011-02-22 07:16:58 +00001259 const VarDecl &D = *emission.Variable;
John McCall34695852011-02-22 06:44:22 +00001260
Nadav Rotem495cfa42013-03-23 06:43:35 +00001261 // Make sure we call @llvm.lifetime.end. This needs to happen
1262 // *last*, so the cleanup needs to be pushed *first*.
1263 if (emission.useLifetimeMarkers()) {
1264 EHStack.pushCleanup<CallLifetimeEnd>(NormalCleanup,
1265 emission.getAllocatedAddress(),
1266 emission.getSizeForLifetimeMarkers());
1267 }
1268
John McCallbdc4d802011-07-09 01:37:26 +00001269 // Check the type for a cleanup.
1270 if (QualType::DestructionKind dtorKind = D.getType().isDestructedType())
1271 emitAutoVarTypeCleanup(emission, dtorKind);
John McCallf85e1932011-06-15 23:02:42 +00001272
John McCall0c24c802011-06-24 23:21:27 +00001273 // In GC mode, honor objc_precise_lifetime.
David Blaikie4e4d0842012-03-11 07:00:24 +00001274 if (getLangOpts().getGC() != LangOptions::NonGC &&
John McCall0c24c802011-06-24 23:21:27 +00001275 D.hasAttr<ObjCPreciseLifetimeAttr>()) {
1276 EHStack.pushCleanup<ExtendGCLifetime>(NormalCleanup, &D);
1277 }
1278
John McCall34695852011-02-22 06:44:22 +00001279 // Handle the cleanup attribute.
Argyrios Kyrtzidis40b598e2009-06-30 02:34:44 +00001280 if (const CleanupAttr *CA = D.getAttr<CleanupAttr>()) {
Anders Carlsson69c68b72009-02-07 23:51:38 +00001281 const FunctionDecl *FD = CA->getFunctionDecl();
Mike Stump1eb44332009-09-09 15:08:12 +00001282
John McCall34695852011-02-22 06:44:22 +00001283 llvm::Constant *F = CGM.GetAddrOfFunction(FD);
Anders Carlsson69c68b72009-02-07 23:51:38 +00001284 assert(F && "Could not find function!");
Mike Stump1eb44332009-09-09 15:08:12 +00001285
John McCallde5d3c72012-02-17 03:33:10 +00001286 const CGFunctionInfo &Info = CGM.getTypes().arrangeFunctionDeclaration(FD);
John McCall34695852011-02-22 06:44:22 +00001287 EHStack.pushCleanup<CallCleanupFunction>(NormalAndEHCleanup, F, &Info, &D);
Anders Carlsson69c68b72009-02-07 23:51:38 +00001288 }
Mike Stump797b6322009-03-05 01:23:13 +00001289
John McCall34695852011-02-22 06:44:22 +00001290 // If this is a block variable, call _Block_object_destroy
1291 // (on the unforwarded address).
John McCall5af02db2011-03-31 01:59:53 +00001292 if (emission.IsByRef)
1293 enterByrefCleanup(emission);
Reid Spencer5f016e22007-07-11 17:01:13 +00001294}
1295
Peter Collingbourne516bbd42012-01-26 03:33:36 +00001296CodeGenFunction::Destroyer *
John McCallbdc4d802011-07-09 01:37:26 +00001297CodeGenFunction::getDestroyer(QualType::DestructionKind kind) {
1298 switch (kind) {
1299 case QualType::DK_none: llvm_unreachable("no destroyer for trivial dtor");
John McCall0850e8d2011-07-09 09:09:00 +00001300 case QualType::DK_cxx_destructor:
Peter Collingbourne516bbd42012-01-26 03:33:36 +00001301 return destroyCXXObject;
John McCall0850e8d2011-07-09 09:09:00 +00001302 case QualType::DK_objc_strong_lifetime:
Peter Collingbourne516bbd42012-01-26 03:33:36 +00001303 return destroyARCStrongPrecise;
John McCall0850e8d2011-07-09 09:09:00 +00001304 case QualType::DK_objc_weak_lifetime:
Peter Collingbourne516bbd42012-01-26 03:33:36 +00001305 return destroyARCWeak;
John McCallbdc4d802011-07-09 01:37:26 +00001306 }
Matt Beaumont-Gayba4be252012-01-27 00:46:27 +00001307 llvm_unreachable("Unknown DestructionKind");
John McCallbdc4d802011-07-09 01:37:26 +00001308}
1309
John McCall074cae02013-02-01 05:11:40 +00001310/// pushEHDestroy - Push the standard destructor for the given type as
1311/// an EH-only cleanup.
1312void CodeGenFunction::pushEHDestroy(QualType::DestructionKind dtorKind,
1313 llvm::Value *addr, QualType type) {
1314 assert(dtorKind && "cannot push destructor for trivial type");
1315 assert(needsEHCleanup(dtorKind));
1316
1317 pushDestroy(EHCleanup, addr, type, getDestroyer(dtorKind), true);
1318}
1319
1320/// pushDestroy - Push the standard destructor for the given type as
1321/// at least a normal cleanup.
John McCall9928c482011-07-12 16:41:08 +00001322void CodeGenFunction::pushDestroy(QualType::DestructionKind dtorKind,
1323 llvm::Value *addr, QualType type) {
1324 assert(dtorKind && "cannot push destructor for trivial type");
1325
1326 CleanupKind cleanupKind = getCleanupKind(dtorKind);
1327 pushDestroy(cleanupKind, addr, type, getDestroyer(dtorKind),
1328 cleanupKind & EHCleanup);
1329}
1330
John McCallbdc4d802011-07-09 01:37:26 +00001331void CodeGenFunction::pushDestroy(CleanupKind cleanupKind, llvm::Value *addr,
Peter Collingbourne516bbd42012-01-26 03:33:36 +00001332 QualType type, Destroyer *destroyer,
John McCall2673c682011-07-11 08:38:19 +00001333 bool useEHCleanupForArray) {
John McCall9928c482011-07-12 16:41:08 +00001334 pushFullExprCleanup<DestroyObject>(cleanupKind, addr, type,
1335 destroyer, useEHCleanupForArray);
John McCallbdc4d802011-07-09 01:37:26 +00001336}
1337
John McCall2673c682011-07-11 08:38:19 +00001338/// emitDestroy - Immediately perform the destruction of the given
1339/// object.
1340///
1341/// \param addr - the address of the object; a type*
1342/// \param type - the type of the object; if an array type, all
1343/// objects are destroyed in reverse order
1344/// \param destroyer - the function to call to destroy individual
1345/// elements
1346/// \param useEHCleanupForArray - whether an EH cleanup should be
1347/// used when destroying array elements, in case one of the
1348/// destructions throws an exception
John McCallbdc4d802011-07-09 01:37:26 +00001349void CodeGenFunction::emitDestroy(llvm::Value *addr, QualType type,
Peter Collingbourne516bbd42012-01-26 03:33:36 +00001350 Destroyer *destroyer,
John McCall2673c682011-07-11 08:38:19 +00001351 bool useEHCleanupForArray) {
John McCallbdc4d802011-07-09 01:37:26 +00001352 const ArrayType *arrayType = getContext().getAsArrayType(type);
1353 if (!arrayType)
1354 return destroyer(*this, addr, type);
1355
1356 llvm::Value *begin = addr;
1357 llvm::Value *length = emitArrayLength(arrayType, type, begin);
John McCallfbf780a2011-07-13 08:09:46 +00001358
1359 // Normally we have to check whether the array is zero-length.
1360 bool checkZeroLength = true;
1361
1362 // But if the array length is constant, we can suppress that.
1363 if (llvm::ConstantInt *constLength = dyn_cast<llvm::ConstantInt>(length)) {
1364 // ...and if it's constant zero, we can just skip the entire thing.
1365 if (constLength->isZero()) return;
1366 checkZeroLength = false;
1367 }
1368
John McCallbdc4d802011-07-09 01:37:26 +00001369 llvm::Value *end = Builder.CreateInBoundsGEP(begin, length);
John McCallfbf780a2011-07-13 08:09:46 +00001370 emitArrayDestroy(begin, end, type, destroyer,
1371 checkZeroLength, useEHCleanupForArray);
John McCallbdc4d802011-07-09 01:37:26 +00001372}
1373
John McCall2673c682011-07-11 08:38:19 +00001374/// emitArrayDestroy - Destroys all the elements of the given array,
1375/// beginning from last to first. The array cannot be zero-length.
1376///
1377/// \param begin - a type* denoting the first element of the array
1378/// \param end - a type* denoting one past the end of the array
1379/// \param type - the element type of the array
1380/// \param destroyer - the function to call to destroy elements
1381/// \param useEHCleanup - whether to push an EH cleanup to destroy
1382/// the remaining elements in case the destruction of a single
1383/// element throws
John McCallbdc4d802011-07-09 01:37:26 +00001384void CodeGenFunction::emitArrayDestroy(llvm::Value *begin,
1385 llvm::Value *end,
1386 QualType type,
Peter Collingbourne516bbd42012-01-26 03:33:36 +00001387 Destroyer *destroyer,
John McCallfbf780a2011-07-13 08:09:46 +00001388 bool checkZeroLength,
John McCall2673c682011-07-11 08:38:19 +00001389 bool useEHCleanup) {
John McCallbdc4d802011-07-09 01:37:26 +00001390 assert(!type->isArrayType());
1391
1392 // The basic structure here is a do-while loop, because we don't
1393 // need to check for the zero-element case.
1394 llvm::BasicBlock *bodyBB = createBasicBlock("arraydestroy.body");
1395 llvm::BasicBlock *doneBB = createBasicBlock("arraydestroy.done");
1396
John McCallfbf780a2011-07-13 08:09:46 +00001397 if (checkZeroLength) {
1398 llvm::Value *isEmpty = Builder.CreateICmpEQ(begin, end,
1399 "arraydestroy.isempty");
1400 Builder.CreateCondBr(isEmpty, doneBB, bodyBB);
1401 }
1402
John McCallbdc4d802011-07-09 01:37:26 +00001403 // Enter the loop body, making that address the current address.
1404 llvm::BasicBlock *entryBB = Builder.GetInsertBlock();
1405 EmitBlock(bodyBB);
1406 llvm::PHINode *elementPast =
1407 Builder.CreatePHI(begin->getType(), 2, "arraydestroy.elementPast");
1408 elementPast->addIncoming(end, entryBB);
1409
1410 // Shift the address back by one element.
1411 llvm::Value *negativeOne = llvm::ConstantInt::get(SizeTy, -1, true);
1412 llvm::Value *element = Builder.CreateInBoundsGEP(elementPast, negativeOne,
1413 "arraydestroy.element");
1414
John McCall2673c682011-07-11 08:38:19 +00001415 if (useEHCleanup)
1416 pushRegularPartialArrayCleanup(begin, element, type, destroyer);
1417
John McCallbdc4d802011-07-09 01:37:26 +00001418 // Perform the actual destruction there.
1419 destroyer(*this, element, type);
1420
John McCall2673c682011-07-11 08:38:19 +00001421 if (useEHCleanup)
1422 PopCleanupBlock();
1423
John McCallbdc4d802011-07-09 01:37:26 +00001424 // Check whether we've reached the end.
1425 llvm::Value *done = Builder.CreateICmpEQ(element, begin, "arraydestroy.done");
1426 Builder.CreateCondBr(done, doneBB, bodyBB);
1427 elementPast->addIncoming(element, Builder.GetInsertBlock());
1428
1429 // Done.
1430 EmitBlock(doneBB);
1431}
1432
John McCall2673c682011-07-11 08:38:19 +00001433/// Perform partial array destruction as if in an EH cleanup. Unlike
1434/// emitArrayDestroy, the element type here may still be an array type.
John McCall2673c682011-07-11 08:38:19 +00001435static void emitPartialArrayDestroy(CodeGenFunction &CGF,
1436 llvm::Value *begin, llvm::Value *end,
1437 QualType type,
Peter Collingbourne516bbd42012-01-26 03:33:36 +00001438 CodeGenFunction::Destroyer *destroyer) {
John McCall2673c682011-07-11 08:38:19 +00001439 // If the element type is itself an array, drill down.
John McCallfbf780a2011-07-13 08:09:46 +00001440 unsigned arrayDepth = 0;
John McCall2673c682011-07-11 08:38:19 +00001441 while (const ArrayType *arrayType = CGF.getContext().getAsArrayType(type)) {
1442 // VLAs don't require a GEP index to walk into.
1443 if (!isa<VariableArrayType>(arrayType))
John McCallfbf780a2011-07-13 08:09:46 +00001444 arrayDepth++;
John McCall2673c682011-07-11 08:38:19 +00001445 type = arrayType->getElementType();
1446 }
John McCallfbf780a2011-07-13 08:09:46 +00001447
1448 if (arrayDepth) {
1449 llvm::Value *zero = llvm::ConstantInt::get(CGF.SizeTy, arrayDepth+1);
1450
Chris Lattner5f9e2722011-07-23 10:55:15 +00001451 SmallVector<llvm::Value*,4> gepIndices(arrayDepth, zero);
Jay Foad0f6ac7c2011-07-22 08:16:57 +00001452 begin = CGF.Builder.CreateInBoundsGEP(begin, gepIndices, "pad.arraybegin");
1453 end = CGF.Builder.CreateInBoundsGEP(end, gepIndices, "pad.arrayend");
John McCall2673c682011-07-11 08:38:19 +00001454 }
1455
John McCallfbf780a2011-07-13 08:09:46 +00001456 // Destroy the array. We don't ever need an EH cleanup because we
1457 // assume that we're in an EH cleanup ourselves, so a throwing
1458 // destructor causes an immediate terminate.
1459 CGF.emitArrayDestroy(begin, end, type, destroyer,
1460 /*checkZeroLength*/ true, /*useEHCleanup*/ false);
John McCall2673c682011-07-11 08:38:19 +00001461}
1462
John McCallbdc4d802011-07-09 01:37:26 +00001463namespace {
John McCall2673c682011-07-11 08:38:19 +00001464 /// RegularPartialArrayDestroy - a cleanup which performs a partial
1465 /// array destroy where the end pointer is regularly determined and
1466 /// does not need to be loaded from a local.
1467 class RegularPartialArrayDestroy : public EHScopeStack::Cleanup {
1468 llvm::Value *ArrayBegin;
1469 llvm::Value *ArrayEnd;
1470 QualType ElementType;
Peter Collingbourne516bbd42012-01-26 03:33:36 +00001471 CodeGenFunction::Destroyer *Destroyer;
John McCall2673c682011-07-11 08:38:19 +00001472 public:
1473 RegularPartialArrayDestroy(llvm::Value *arrayBegin, llvm::Value *arrayEnd,
1474 QualType elementType,
1475 CodeGenFunction::Destroyer *destroyer)
1476 : ArrayBegin(arrayBegin), ArrayEnd(arrayEnd),
Peter Collingbourne516bbd42012-01-26 03:33:36 +00001477 ElementType(elementType), Destroyer(destroyer) {}
John McCall2673c682011-07-11 08:38:19 +00001478
John McCallad346f42011-07-12 20:27:29 +00001479 void Emit(CodeGenFunction &CGF, Flags flags) {
John McCall2673c682011-07-11 08:38:19 +00001480 emitPartialArrayDestroy(CGF, ArrayBegin, ArrayEnd,
1481 ElementType, Destroyer);
1482 }
1483 };
1484
1485 /// IrregularPartialArrayDestroy - a cleanup which performs a
1486 /// partial array destroy where the end pointer is irregularly
1487 /// determined and must be loaded from a local.
1488 class IrregularPartialArrayDestroy : public EHScopeStack::Cleanup {
John McCallbdc4d802011-07-09 01:37:26 +00001489 llvm::Value *ArrayBegin;
1490 llvm::Value *ArrayEndPointer;
1491 QualType ElementType;
Peter Collingbourne516bbd42012-01-26 03:33:36 +00001492 CodeGenFunction::Destroyer *Destroyer;
John McCallbdc4d802011-07-09 01:37:26 +00001493 public:
John McCall2673c682011-07-11 08:38:19 +00001494 IrregularPartialArrayDestroy(llvm::Value *arrayBegin,
1495 llvm::Value *arrayEndPointer,
1496 QualType elementType,
1497 CodeGenFunction::Destroyer *destroyer)
John McCallbdc4d802011-07-09 01:37:26 +00001498 : ArrayBegin(arrayBegin), ArrayEndPointer(arrayEndPointer),
Peter Collingbourne516bbd42012-01-26 03:33:36 +00001499 ElementType(elementType), Destroyer(destroyer) {}
John McCallbdc4d802011-07-09 01:37:26 +00001500
John McCallad346f42011-07-12 20:27:29 +00001501 void Emit(CodeGenFunction &CGF, Flags flags) {
John McCallbdc4d802011-07-09 01:37:26 +00001502 llvm::Value *arrayEnd = CGF.Builder.CreateLoad(ArrayEndPointer);
John McCall2673c682011-07-11 08:38:19 +00001503 emitPartialArrayDestroy(CGF, ArrayBegin, arrayEnd,
1504 ElementType, Destroyer);
John McCallbdc4d802011-07-09 01:37:26 +00001505 }
1506 };
1507}
1508
John McCall2673c682011-07-11 08:38:19 +00001509/// pushIrregularPartialArrayCleanup - Push an EH cleanup to destroy
John McCallbdc4d802011-07-09 01:37:26 +00001510/// already-constructed elements of the given array. The cleanup
John McCall2673c682011-07-11 08:38:19 +00001511/// may be popped with DeactivateCleanupBlock or PopCleanupBlock.
Eric Christophere1f54902011-08-23 22:38:00 +00001512///
John McCallbdc4d802011-07-09 01:37:26 +00001513/// \param elementType - the immediate element type of the array;
1514/// possibly still an array type
John McCall9928c482011-07-12 16:41:08 +00001515void CodeGenFunction::pushIrregularPartialArrayCleanup(llvm::Value *arrayBegin,
John McCall2673c682011-07-11 08:38:19 +00001516 llvm::Value *arrayEndPointer,
1517 QualType elementType,
Peter Collingbourne516bbd42012-01-26 03:33:36 +00001518 Destroyer *destroyer) {
John McCall9928c482011-07-12 16:41:08 +00001519 pushFullExprCleanup<IrregularPartialArrayDestroy>(EHCleanup,
1520 arrayBegin, arrayEndPointer,
Peter Collingbourne516bbd42012-01-26 03:33:36 +00001521 elementType, destroyer);
John McCall2673c682011-07-11 08:38:19 +00001522}
1523
1524/// pushRegularPartialArrayCleanup - Push an EH cleanup to destroy
1525/// already-constructed elements of the given array. The cleanup
1526/// may be popped with DeactivateCleanupBlock or PopCleanupBlock.
Eric Christophere1f54902011-08-23 22:38:00 +00001527///
John McCall2673c682011-07-11 08:38:19 +00001528/// \param elementType - the immediate element type of the array;
1529/// possibly still an array type
John McCall2673c682011-07-11 08:38:19 +00001530void CodeGenFunction::pushRegularPartialArrayCleanup(llvm::Value *arrayBegin,
1531 llvm::Value *arrayEnd,
1532 QualType elementType,
Peter Collingbourne516bbd42012-01-26 03:33:36 +00001533 Destroyer *destroyer) {
John McCall9928c482011-07-12 16:41:08 +00001534 pushFullExprCleanup<RegularPartialArrayDestroy>(EHCleanup,
John McCall2673c682011-07-11 08:38:19 +00001535 arrayBegin, arrayEnd,
Peter Collingbourne516bbd42012-01-26 03:33:36 +00001536 elementType, destroyer);
John McCallbdc4d802011-07-09 01:37:26 +00001537}
1538
Nadav Rotem495cfa42013-03-23 06:43:35 +00001539/// Lazily declare the @llvm.lifetime.start intrinsic.
1540llvm::Constant *CodeGenModule::getLLVMLifetimeStartFn() {
1541 if (LifetimeStartFn) return LifetimeStartFn;
1542 LifetimeStartFn = llvm::Intrinsic::getDeclaration(&getModule(),
1543 llvm::Intrinsic::lifetime_start);
1544 return LifetimeStartFn;
1545}
1546
1547/// Lazily declare the @llvm.lifetime.end intrinsic.
1548llvm::Constant *CodeGenModule::getLLVMLifetimeEndFn() {
1549 if (LifetimeEndFn) return LifetimeEndFn;
1550 LifetimeEndFn = llvm::Intrinsic::getDeclaration(&getModule(),
1551 llvm::Intrinsic::lifetime_end);
1552 return LifetimeEndFn;
1553}
1554
John McCallf85e1932011-06-15 23:02:42 +00001555namespace {
1556 /// A cleanup to perform a release of an object at the end of a
1557 /// function. This is used to balance out the incoming +1 of a
1558 /// ns_consumed argument when we can't reasonably do that just by
1559 /// not doing the initial retain for a __block argument.
1560 struct ConsumeARCParameter : EHScopeStack::Cleanup {
John McCall5b07e802013-03-13 03:10:54 +00001561 ConsumeARCParameter(llvm::Value *param,
1562 ARCPreciseLifetime_t precise)
1563 : Param(param), Precise(precise) {}
John McCallf85e1932011-06-15 23:02:42 +00001564
1565 llvm::Value *Param;
John McCall5b07e802013-03-13 03:10:54 +00001566 ARCPreciseLifetime_t Precise;
John McCallf85e1932011-06-15 23:02:42 +00001567
John McCallad346f42011-07-12 20:27:29 +00001568 void Emit(CodeGenFunction &CGF, Flags flags) {
John McCall5b07e802013-03-13 03:10:54 +00001569 CGF.EmitARCRelease(Param, Precise);
John McCallf85e1932011-06-15 23:02:42 +00001570 }
1571 };
1572}
1573
Mike Stump1eb44332009-09-09 15:08:12 +00001574/// Emit an alloca (or GlobalValue depending on target)
Chris Lattner2621fd12008-05-08 05:58:21 +00001575/// for the specified parameter and set up LocalDeclMap.
Devang Patel093ac462011-03-03 20:13:15 +00001576void CodeGenFunction::EmitParmDecl(const VarDecl &D, llvm::Value *Arg,
1577 unsigned ArgNo) {
Daniel Dunbarb7ec2462008-08-16 03:19:19 +00001578 // FIXME: Why isn't ImplicitParamDecl a ParmVarDecl?
Sanjiv Gupta31fc07d2008-10-31 09:52:39 +00001579 assert((isa<ParmVarDecl>(D) || isa<ImplicitParamDecl>(D)) &&
Daniel Dunbarb7ec2462008-08-16 03:19:19 +00001580 "Invalid argument to EmitParmDecl");
John McCall8178df32011-02-22 22:38:33 +00001581
1582 Arg->setName(D.getName());
1583
Adrian Prantl836e7c92013-03-14 17:53:33 +00001584 QualType Ty = D.getType();
1585
John McCall8178df32011-02-22 22:38:33 +00001586 // Use better IR generation for certain implicit parameters.
1587 if (isa<ImplicitParamDecl>(D)) {
1588 // The only implicit argument a block has is its literal.
1589 if (BlockInfo) {
1590 LocalDeclMap[&D] = Arg;
Adrian Prantl836e7c92013-03-14 17:53:33 +00001591 llvm::Value *LocalAddr = 0;
1592 if (CGM.getCodeGenOpts().OptimizationLevel == 0) {
1593 // Allocate a stack slot to let debug info survive the RA.
1594 llvm::AllocaInst *Alloc = CreateTempAlloca(ConvertTypeForMem(Ty),
1595 D.getName() + ".addr");
1596 Alloc->setAlignment(getContext().getDeclAlign(&D).getQuantity());
1597 LValue lv = MakeAddrLValue(Alloc, Ty, getContext().getDeclAlign(&D));
1598 EmitStoreOfScalar(Arg, lv, /* isInitialization */ true);
1599 LocalAddr = Builder.CreateLoad(Alloc);
1600 }
John McCall8178df32011-02-22 22:38:33 +00001601
1602 if (CGDebugInfo *DI = getDebugInfo()) {
Douglas Gregor4cdad312012-10-23 20:05:01 +00001603 if (CGM.getCodeGenOpts().getDebugInfo()
1604 >= CodeGenOptions::LimitedDebugInfo) {
Alexey Samsonovfd00eec2012-05-04 07:39:27 +00001605 DI->setLocation(D.getLocation());
Adrian Prantl836e7c92013-03-14 17:53:33 +00001606 DI->EmitDeclareOfBlockLiteralArgVariable(*BlockInfo, Arg, LocalAddr, Builder);
Alexey Samsonovfd00eec2012-05-04 07:39:27 +00001607 }
John McCall8178df32011-02-22 22:38:33 +00001608 }
1609
1610 return;
1611 }
1612 }
1613
Reid Spencer5f016e22007-07-11 17:01:13 +00001614 llvm::Value *DeclPtr;
Daniel Dunbare86bcf02010-02-08 22:53:07 +00001615 // If this is an aggregate or variable sized value, reuse the input pointer.
1616 if (!Ty->isConstantSizeType() ||
John McCall9d232c82013-03-07 21:37:08 +00001617 !CodeGenFunction::hasScalarEvaluationKind(Ty)) {
Reid Spencer5f016e22007-07-11 17:01:13 +00001618 DeclPtr = Arg;
Reid Spencer5f016e22007-07-11 17:01:13 +00001619 } else {
Daniel Dunbare86bcf02010-02-08 22:53:07 +00001620 // Otherwise, create a temporary to hold the value.
Eli Friedmanddfb8d12011-11-03 20:31:28 +00001621 llvm::AllocaInst *Alloc = CreateTempAlloca(ConvertTypeForMem(Ty),
1622 D.getName() + ".addr");
Fariborz Jahanian41a6a3e2013-02-21 00:40:10 +00001623 CharUnits Align = getContext().getDeclAlign(&D);
1624 Alloc->setAlignment(Align.getQuantity());
Eli Friedmanddfb8d12011-11-03 20:31:28 +00001625 DeclPtr = Alloc;
Mike Stump1eb44332009-09-09 15:08:12 +00001626
John McCallf85e1932011-06-15 23:02:42 +00001627 bool doStore = true;
1628
1629 Qualifiers qs = Ty.getQualifiers();
Fariborz Jahanian41a6a3e2013-02-21 00:40:10 +00001630 LValue lv = MakeAddrLValue(DeclPtr, Ty, Align);
John McCallf85e1932011-06-15 23:02:42 +00001631 if (Qualifiers::ObjCLifetime lt = qs.getObjCLifetime()) {
1632 // We honor __attribute__((ns_consumed)) for types with lifetime.
1633 // For __strong, it's handled by just skipping the initial retain;
1634 // otherwise we have to balance out the initial +1 with an extra
1635 // cleanup to do the release at the end of the function.
1636 bool isConsumed = D.hasAttr<NSConsumedAttr>();
1637
1638 // 'self' is always formally __strong, but if this is not an
1639 // init method then we don't want to retain it.
John McCall7acddac2011-06-17 06:42:21 +00001640 if (D.isARCPseudoStrong()) {
John McCallf85e1932011-06-15 23:02:42 +00001641 const ObjCMethodDecl *method = cast<ObjCMethodDecl>(CurCodeDecl);
1642 assert(&D == method->getSelfDecl());
John McCall7acddac2011-06-17 06:42:21 +00001643 assert(lt == Qualifiers::OCL_Strong);
1644 assert(qs.hasConst());
John McCallf85e1932011-06-15 23:02:42 +00001645 assert(method->getMethodFamily() != OMF_init);
John McCall175d6592011-06-15 23:40:09 +00001646 (void) method;
John McCallf85e1932011-06-15 23:02:42 +00001647 lt = Qualifiers::OCL_ExplicitNone;
1648 }
1649
1650 if (lt == Qualifiers::OCL_Strong) {
Fariborz Jahanian41a6a3e2013-02-21 00:40:10 +00001651 if (!isConsumed) {
1652 if (CGM.getCodeGenOpts().OptimizationLevel == 0) {
1653 // use objc_storeStrong(&dest, value) for retaining the
1654 // object. But first, store a null into 'dest' because
1655 // objc_storeStrong attempts to release its old value.
1656 llvm::Value * Null = CGM.EmitNullConstant(D.getType());
1657 EmitStoreOfScalar(Null, lv, /* isInitialization */ true);
1658 EmitARCStoreStrongCall(lv.getAddress(), Arg, true);
1659 doStore = false;
1660 }
1661 else
John McCallf85e1932011-06-15 23:02:42 +00001662 // Don't use objc_retainBlock for block pointers, because we
1663 // don't want to Block_copy something just because we got it
1664 // as a parameter.
Fariborz Jahanian41a6a3e2013-02-21 00:40:10 +00001665 Arg = EmitARCRetainNonBlock(Arg);
1666 }
John McCallf85e1932011-06-15 23:02:42 +00001667 } else {
1668 // Push the cleanup for a consumed parameter.
John McCall5b07e802013-03-13 03:10:54 +00001669 if (isConsumed) {
1670 ARCPreciseLifetime_t precise = (D.hasAttr<ObjCPreciseLifetimeAttr>()
1671 ? ARCPreciseLifetime : ARCImpreciseLifetime);
1672 EHStack.pushCleanup<ConsumeARCParameter>(getARCCleanupKind(), Arg,
1673 precise);
1674 }
John McCallf85e1932011-06-15 23:02:42 +00001675
1676 if (lt == Qualifiers::OCL_Weak) {
1677 EmitARCInitWeak(DeclPtr, Arg);
Chad Rosier7acebfb2012-02-18 01:20:35 +00001678 doStore = false; // The weak init is a store, no need to do two.
John McCallf85e1932011-06-15 23:02:42 +00001679 }
1680 }
1681
1682 // Enter the cleanup scope.
1683 EmitAutoVarWithLifetime(*this, D, DeclPtr, lt);
1684 }
1685
Daniel Dunbare86bcf02010-02-08 22:53:07 +00001686 // Store the initial value into the alloca.
Fariborz Jahanian41a6a3e2013-02-21 00:40:10 +00001687 if (doStore)
David Chisnall7a7ee302012-01-16 17:27:18 +00001688 EmitStoreOfScalar(Arg, lv, /* isInitialization */ true);
Reid Spencer5f016e22007-07-11 17:01:13 +00001689 }
1690
1691 llvm::Value *&DMEntry = LocalDeclMap[&D];
1692 assert(DMEntry == 0 && "Decl already exists in localdeclmap!");
1693 DMEntry = DeclPtr;
Sanjiv Guptacc9b1632008-05-30 10:30:31 +00001694
1695 // Emit debug info for param declaration.
Alexey Samsonovfd00eec2012-05-04 07:39:27 +00001696 if (CGDebugInfo *DI = getDebugInfo()) {
Douglas Gregor4cdad312012-10-23 20:05:01 +00001697 if (CGM.getCodeGenOpts().getDebugInfo()
1698 >= CodeGenOptions::LimitedDebugInfo) {
Alexey Samsonovfd00eec2012-05-04 07:39:27 +00001699 DI->EmitDeclareOfArgVariable(&D, DeclPtr, ArgNo, Builder);
1700 }
1701 }
Julien Lerouge77f68bb2011-09-09 22:41:49 +00001702
1703 if (D.hasAttr<AnnotateAttr>())
1704 EmitVarAnnotations(&D, DeclPtr);
Reid Spencer5f016e22007-07-11 17:01:13 +00001705}