blob: 5375c5e18f2f8a3484de99cdf5bd6fc90dcd81ae [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 Espindolad2615cc2013-04-03 19:27:57 +0000112 switch (D.getStorageClass()) {
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) {
Alexey Samsonov4f01ed42013-04-02 13:19:46 +0000789 // Always emit lifetime markers in -fsanitize=use-after-scope mode.
790 if (CGF.getLangOpts().Sanitize.UseAfterScope)
791 return true;
Nadav Rotem495cfa42013-03-23 06:43:35 +0000792 // For now, only in optimized builds.
793 if (CGF.CGM.getCodeGenOpts().OptimizationLevel == 0)
794 return false;
795
796 // Limit the size of marked objects to 32 bytes. We don't want to increase
797 // compile time by marking tiny objects.
798 unsigned SizeThreshold = 32;
799
800 return Size > SizeThreshold;
801}
802
Chris Lattner94cd0112010-12-01 02:05:19 +0000803
Nick Lewyckya9de3fa2010-12-30 20:21:55 +0000804/// EmitAutoVarDecl - Emit code and set up an entry in LocalDeclMap for a
Reid Spencer5f016e22007-07-11 17:01:13 +0000805/// variable declaration with auto, register, or no storage class specifier.
Chris Lattner2621fd12008-05-08 05:58:21 +0000806/// These turn into simple stack objects, or GlobalValues depending on target.
John McCall34695852011-02-22 06:44:22 +0000807void CodeGenFunction::EmitAutoVarDecl(const VarDecl &D) {
808 AutoVarEmission emission = EmitAutoVarAlloca(D);
809 EmitAutoVarInit(emission);
810 EmitAutoVarCleanups(emission);
811}
Reid Spencer5f016e22007-07-11 17:01:13 +0000812
John McCall34695852011-02-22 06:44:22 +0000813/// EmitAutoVarAlloca - Emit the alloca and debug information for a
814/// local variable. Does not emit initalization or destruction.
815CodeGenFunction::AutoVarEmission
816CodeGenFunction::EmitAutoVarAlloca(const VarDecl &D) {
817 QualType Ty = D.getType();
818
819 AutoVarEmission emission(D);
820
821 bool isByRef = D.hasAttr<BlocksAttr>();
822 emission.IsByRef = isByRef;
823
824 CharUnits alignment = getContext().getDeclAlign(&D);
825 emission.Alignment = alignment;
826
John McCallbc8d40d2011-06-24 21:55:10 +0000827 // If the type is variably-modified, emit all the VLA sizes for it.
828 if (Ty->isVariablyModifiedType())
829 EmitVariablyModifiedType(Ty);
830
Reid Spencer5f016e22007-07-11 17:01:13 +0000831 llvm::Value *DeclPtr;
Eli Friedman3c2b3172008-02-15 12:20:59 +0000832 if (Ty->isConstantSizeType()) {
Rafael Espindola6c82fc62013-03-26 18:41:47 +0000833 bool NRVO = getLangOpts().ElideConstructors &&
834 D.isNRVOVariable();
John McCall34695852011-02-22 06:44:22 +0000835
Rafael Espindola6c82fc62013-03-26 18:41:47 +0000836 // If this value is a POD array or struct with a statically
837 // determinable constant initializer, there are optimizations we can do.
838 //
839 // TODO: We should constant-evaluate the initializer of any variable,
840 // as long as it is initialized by a constant expression. Currently,
841 // isConstantInitializer produces wrong answers for structs with
842 // reference or bitfield members, and a few other cases, and checking
843 // for POD-ness protects us from some of these.
844 if (D.getInit() &&
845 (Ty->isArrayType() || Ty->isRecordType()) &&
846 (Ty.isPODType(getContext()) ||
847 getContext().getBaseElementType(Ty)->isObjCObjectPointerType()) &&
848 D.getInit()->isConstantInitializer(getContext(), false)) {
John McCall34695852011-02-22 06:44:22 +0000849
Rafael Espindola6c82fc62013-03-26 18:41:47 +0000850 // If the variable's a const type, and it's neither an NRVO
851 // candidate nor a __block variable and has no mutable members,
852 // emit it as a global instead.
853 if (CGM.getCodeGenOpts().MergeAllConstants && !NRVO && !isByRef &&
854 CGM.isTypeConstant(Ty, true)) {
855 EmitStaticVarDecl(D, llvm::GlobalValue::InternalLinkage);
John McCall34695852011-02-22 06:44:22 +0000856
Rafael Espindola6c82fc62013-03-26 18:41:47 +0000857 emission.Address = 0; // signal this condition to later callbacks
858 assert(emission.wasEmittedAsGlobal());
859 return emission;
Tanya Lattner59876c22009-11-04 01:18:09 +0000860 }
Eric Christophere1f54902011-08-23 22:38:00 +0000861
Rafael Espindola6c82fc62013-03-26 18:41:47 +0000862 // Otherwise, tell the initialization code that we're in this case.
863 emission.IsConstantAggregate = true;
864 }
Eric Christophere1f54902011-08-23 22:38:00 +0000865
Rafael Espindola6c82fc62013-03-26 18:41:47 +0000866 // A normal fixed sized variable becomes an alloca in the entry block,
867 // unless it's an NRVO variable.
868 llvm::Type *LTy = ConvertTypeForMem(Ty);
Eric Christophere1f54902011-08-23 22:38:00 +0000869
Rafael Espindola6c82fc62013-03-26 18:41:47 +0000870 if (NRVO) {
871 // The named return value optimization: allocate this variable in the
872 // return slot, so that we can elide the copy when returning this
873 // variable (C++0x [class.copy]p34).
874 DeclPtr = ReturnValue;
Eric Christophere1f54902011-08-23 22:38:00 +0000875
Rafael Espindola6c82fc62013-03-26 18:41:47 +0000876 if (const RecordType *RecordTy = Ty->getAs<RecordType>()) {
877 if (!cast<CXXRecordDecl>(RecordTy->getDecl())->hasTrivialDestructor()) {
878 // Create a flag that is used to indicate when the NRVO was applied
879 // to this variable. Set it to zero to indicate that NRVO was not
880 // applied.
881 llvm::Value *Zero = Builder.getFalse();
882 llvm::Value *NRVOFlag = CreateTempAlloca(Zero->getType(), "nrvo");
883 EnsureInsertPoint();
884 Builder.CreateStore(Zero, NRVOFlag);
Eric Christophere1f54902011-08-23 22:38:00 +0000885
Rafael Espindola6c82fc62013-03-26 18:41:47 +0000886 // Record the NRVO flag for this variable.
887 NRVOFlags[&D] = NRVOFlag;
888 emission.NRVOFlag = NRVOFlag;
Nadav Rotem495cfa42013-03-23 06:43:35 +0000889 }
Douglas Gregord86c4772010-05-15 06:46:45 +0000890 }
Chris Lattner2621fd12008-05-08 05:58:21 +0000891 } else {
Rafael Espindola6c82fc62013-03-26 18:41:47 +0000892 if (isByRef)
893 LTy = BuildByRefType(&D);
894
895 llvm::AllocaInst *Alloc = CreateTempAlloca(LTy);
896 Alloc->setName(D.getName());
897
898 CharUnits allocaAlignment = alignment;
899 if (isByRef)
900 allocaAlignment = std::max(allocaAlignment,
901 getContext().toCharUnitsFromBits(Target.getPointerAlign(0)));
902 Alloc->setAlignment(allocaAlignment.getQuantity());
903 DeclPtr = Alloc;
904
905 // Emit a lifetime intrinsic if meaningful. There's no point
906 // in doing this if we don't have a valid insertion point (?).
907 uint64_t size = CGM.getDataLayout().getTypeAllocSize(LTy);
908 if (HaveInsertPoint() && shouldUseLifetimeMarkers(*this, D, size)) {
909 llvm::Value *sizeV = llvm::ConstantInt::get(Int64Ty, size);
910
911 emission.SizeForLifetimeMarkers = sizeV;
912 llvm::Value *castAddr = Builder.CreateBitCast(Alloc, Int8PtrTy);
913 Builder.CreateCall2(CGM.getLLVMLifetimeStartFn(), sizeV, castAddr)
914 ->setDoesNotThrow();
915 } else {
916 assert(!emission.useLifetimeMarkers());
917 }
Chris Lattner2621fd12008-05-08 05:58:21 +0000918 }
Reid Spencer5f016e22007-07-11 17:01:13 +0000919 } else {
Daniel Dunbard286f052009-07-19 06:58:07 +0000920 EnsureInsertPoint();
921
Anders Carlsson5ecb1b92009-02-09 20:41:50 +0000922 if (!DidCallStackSave) {
Anders Carlsson5d463152008-12-12 07:38:43 +0000923 // Save the stack.
John McCalld16c2cf2011-02-08 08:22:06 +0000924 llvm::Value *Stack = CreateTempAlloca(Int8PtrTy, "saved_stack");
Mike Stump1eb44332009-09-09 15:08:12 +0000925
Anders Carlsson5d463152008-12-12 07:38:43 +0000926 llvm::Value *F = CGM.getIntrinsic(llvm::Intrinsic::stacksave);
927 llvm::Value *V = Builder.CreateCall(F);
Mike Stump1eb44332009-09-09 15:08:12 +0000928
Anders Carlsson5d463152008-12-12 07:38:43 +0000929 Builder.CreateStore(V, Stack);
Anders Carlsson5ecb1b92009-02-09 20:41:50 +0000930
931 DidCallStackSave = true;
Mike Stump1eb44332009-09-09 15:08:12 +0000932
John McCalld8715092010-07-21 06:13:08 +0000933 // Push a cleanup block and restore the stack there.
John McCall3ad32c82011-01-28 08:37:24 +0000934 // FIXME: in general circumstances, this should be an EH cleanup.
John McCall1f0fca52010-07-21 07:22:38 +0000935 EHStack.pushCleanup<CallStackRestore>(NormalCleanup, Stack);
Anders Carlsson5d463152008-12-12 07:38:43 +0000936 }
Mike Stump1eb44332009-09-09 15:08:12 +0000937
John McCallbc8d40d2011-06-24 21:55:10 +0000938 llvm::Value *elementCount;
939 QualType elementType;
940 llvm::tie(elementCount, elementType) = getVLASize(Ty);
Anders Carlsson5d463152008-12-12 07:38:43 +0000941
Chris Lattner2acc6e32011-07-18 04:24:23 +0000942 llvm::Type *llvmTy = ConvertTypeForMem(elementType);
Anders Carlsson5d463152008-12-12 07:38:43 +0000943
944 // Allocate memory for the array.
John McCallbc8d40d2011-06-24 21:55:10 +0000945 llvm::AllocaInst *vla = Builder.CreateAlloca(llvmTy, elementCount, "vla");
946 vla->setAlignment(alignment.getQuantity());
Anders Carlsson41f8a132009-09-26 18:16:06 +0000947
John McCallbc8d40d2011-06-24 21:55:10 +0000948 DeclPtr = vla;
Reid Spencer5f016e22007-07-11 17:01:13 +0000949 }
Eli Friedman8f39f5e2008-12-20 23:11:59 +0000950
Reid Spencer5f016e22007-07-11 17:01:13 +0000951 llvm::Value *&DMEntry = LocalDeclMap[&D];
952 assert(DMEntry == 0 && "Decl already exists in localdeclmap!");
953 DMEntry = DeclPtr;
John McCall34695852011-02-22 06:44:22 +0000954 emission.Address = DeclPtr;
Sanjiv Guptacc9b1632008-05-30 10:30:31 +0000955
956 // Emit debug info for local var declaration.
Devang Patelc594abd2011-06-03 19:21:47 +0000957 if (HaveInsertPoint())
958 if (CGDebugInfo *DI = getDebugInfo()) {
Douglas Gregor4cdad312012-10-23 20:05:01 +0000959 if (CGM.getCodeGenOpts().getDebugInfo()
960 >= CodeGenOptions::LimitedDebugInfo) {
Alexey Samsonovfd00eec2012-05-04 07:39:27 +0000961 DI->setLocation(D.getLocation());
Rafael Espindola6c82fc62013-03-26 18:41:47 +0000962 DI->EmitDeclareOfAutoVariable(&D, DeclPtr, Builder);
Alexey Samsonovfd00eec2012-05-04 07:39:27 +0000963 }
Devang Patelc594abd2011-06-03 19:21:47 +0000964 }
Sanjiv Guptacc9b1632008-05-30 10:30:31 +0000965
Julien Lerouge77f68bb2011-09-09 22:41:49 +0000966 if (D.hasAttr<AnnotateAttr>())
967 EmitVarAnnotations(&D, emission.Address);
968
John McCall34695852011-02-22 06:44:22 +0000969 return emission;
970}
971
972/// Determines whether the given __block variable is potentially
973/// captured by the given expression.
974static bool isCapturedBy(const VarDecl &var, const Expr *e) {
975 // Skip the most common kinds of expressions that make
976 // hierarchy-walking expensive.
977 e = e->IgnoreParenCasts();
978
979 if (const BlockExpr *be = dyn_cast<BlockExpr>(e)) {
980 const BlockDecl *block = be->getBlockDecl();
981 for (BlockDecl::capture_const_iterator i = block->capture_begin(),
982 e = block->capture_end(); i != e; ++i) {
983 if (i->getVariable() == &var)
984 return true;
985 }
986
987 // No need to walk into the subexpressions.
988 return false;
989 }
990
Fariborz Jahanian5033be12011-08-23 16:47:15 +0000991 if (const StmtExpr *SE = dyn_cast<StmtExpr>(e)) {
992 const CompoundStmt *CS = SE->getSubStmt();
Eric Christopherc6fad602011-08-23 23:44:09 +0000993 for (CompoundStmt::const_body_iterator BI = CS->body_begin(),
994 BE = CS->body_end(); BI != BE; ++BI)
Fariborz Jahanian045c8422011-08-25 00:06:26 +0000995 if (Expr *E = dyn_cast<Expr>((*BI))) {
Fariborz Jahanian5033be12011-08-23 16:47:15 +0000996 if (isCapturedBy(var, E))
997 return true;
Fariborz Jahanian045c8422011-08-25 00:06:26 +0000998 }
999 else if (DeclStmt *DS = dyn_cast<DeclStmt>((*BI))) {
1000 // special case declarations
1001 for (DeclStmt::decl_iterator I = DS->decl_begin(), E = DS->decl_end();
1002 I != E; ++I) {
1003 if (VarDecl *VD = dyn_cast<VarDecl>((*I))) {
1004 Expr *Init = VD->getInit();
1005 if (Init && isCapturedBy(var, Init))
1006 return true;
1007 }
1008 }
1009 }
1010 else
1011 // FIXME. Make safe assumption assuming arbitrary statements cause capturing.
1012 // Later, provide code to poke into statements for capture analysis.
1013 return true;
Fariborz Jahanian5033be12011-08-23 16:47:15 +00001014 return false;
1015 }
Eric Christophere1f54902011-08-23 22:38:00 +00001016
John McCall34695852011-02-22 06:44:22 +00001017 for (Stmt::const_child_range children = e->children(); children; ++children)
1018 if (isCapturedBy(var, cast<Expr>(*children)))
1019 return true;
1020
1021 return false;
1022}
1023
Douglas Gregorbcc3e662011-07-01 21:08:19 +00001024/// \brief Determine whether the given initializer is trivial in the sense
1025/// that it requires no code to be generated.
1026static bool isTrivialInitializer(const Expr *Init) {
1027 if (!Init)
1028 return true;
Eric Christophere1f54902011-08-23 22:38:00 +00001029
Douglas Gregorbcc3e662011-07-01 21:08:19 +00001030 if (const CXXConstructExpr *Construct = dyn_cast<CXXConstructExpr>(Init))
1031 if (CXXConstructorDecl *Constructor = Construct->getConstructor())
1032 if (Constructor->isTrivial() &&
1033 Constructor->isDefaultConstructor() &&
1034 !Construct->requiresZeroInitialization())
1035 return true;
Eric Christophere1f54902011-08-23 22:38:00 +00001036
Douglas Gregorbcc3e662011-07-01 21:08:19 +00001037 return false;
1038}
John McCall34695852011-02-22 06:44:22 +00001039void CodeGenFunction::EmitAutoVarInit(const AutoVarEmission &emission) {
John McCall57b3b6a2011-02-22 07:16:58 +00001040 assert(emission.Variable && "emission was not valid!");
1041
John McCall34695852011-02-22 06:44:22 +00001042 // If this was emitted as a global constant, we're done.
1043 if (emission.wasEmittedAsGlobal()) return;
1044
John McCall57b3b6a2011-02-22 07:16:58 +00001045 const VarDecl &D = *emission.Variable;
John McCall34695852011-02-22 06:44:22 +00001046 QualType type = D.getType();
1047
Chris Lattner19785962007-07-12 00:39:48 +00001048 // If this local has an initializer, emit it now.
Daniel Dunbard286f052009-07-19 06:58:07 +00001049 const Expr *Init = D.getInit();
1050
1051 // If we are at an unreachable point, we don't need to emit the initializer
1052 // unless it contains a label.
1053 if (!HaveInsertPoint()) {
John McCall34695852011-02-22 06:44:22 +00001054 if (!Init || !ContainsLabel(Init)) return;
1055 EnsureInsertPoint();
Daniel Dunbard286f052009-07-19 06:58:07 +00001056 }
1057
John McCall5af02db2011-03-31 01:59:53 +00001058 // Initialize the structure of a __block variable.
1059 if (emission.IsByRef)
1060 emitByrefStructureInit(emission);
Anders Carlsson69c68b72009-02-07 23:51:38 +00001061
Douglas Gregorbcc3e662011-07-01 21:08:19 +00001062 if (isTrivialInitializer(Init))
1063 return;
Eric Christophere1f54902011-08-23 22:38:00 +00001064
John McCall5af02db2011-03-31 01:59:53 +00001065 CharUnits alignment = emission.Alignment;
1066
John McCall34695852011-02-22 06:44:22 +00001067 // Check whether this is a byref variable that's potentially
1068 // captured and moved by its own initializer. If so, we'll need to
1069 // emit the initializer first, then copy into the variable.
1070 bool capturedByInit = emission.IsByRef && isCapturedBy(D, Init);
1071
1072 llvm::Value *Loc =
1073 capturedByInit ? emission.Address : emission.getObjectAddress(*this);
1074
Richard Smith51201882011-12-30 21:15:51 +00001075 llvm::Constant *constant = 0;
1076 if (emission.IsConstantAggregate) {
1077 assert(!capturedByInit && "constant init contains a capturing block?");
Richard Smith2d6a5672012-01-14 04:30:29 +00001078 constant = CGM.EmitConstantInit(D, this);
Richard Smith51201882011-12-30 21:15:51 +00001079 }
1080
1081 if (!constant) {
Eli Friedman6da2c712011-12-03 04:14:32 +00001082 LValue lv = MakeAddrLValue(Loc, type, alignment);
John McCalla07398e2011-06-16 04:16:24 +00001083 lv.setNonGC(true);
1084 return EmitExprAsInit(Init, &D, lv, capturedByInit);
1085 }
John McCall60d33652011-03-08 09:11:50 +00001086
John McCall34695852011-02-22 06:44:22 +00001087 // If this is a simple aggregate initialization, we can optimize it
1088 // in various ways.
John McCall60d33652011-03-08 09:11:50 +00001089 bool isVolatile = type.isVolatileQualified();
John McCall34695852011-02-22 06:44:22 +00001090
John McCall60d33652011-03-08 09:11:50 +00001091 llvm::Value *SizeVal =
Eric Christophere1f54902011-08-23 22:38:00 +00001092 llvm::ConstantInt::get(IntPtrTy,
John McCall60d33652011-03-08 09:11:50 +00001093 getContext().getTypeSizeInChars(type).getQuantity());
John McCall34695852011-02-22 06:44:22 +00001094
Chris Lattner2acc6e32011-07-18 04:24:23 +00001095 llvm::Type *BP = Int8PtrTy;
John McCall60d33652011-03-08 09:11:50 +00001096 if (Loc->getType() != BP)
Benjamin Kramer578faa82011-09-27 21:06:10 +00001097 Loc = Builder.CreateBitCast(Loc, BP);
Mon P Wang3ecd7852010-04-04 03:10:52 +00001098
John McCall60d33652011-03-08 09:11:50 +00001099 // If the initializer is all or mostly zeros, codegen with memset then do
1100 // a few stores afterward.
Eric Christophere1f54902011-08-23 22:38:00 +00001101 if (shouldUseMemSetPlusStoresToInitialize(constant,
Micah Villmow25a6a842012-10-08 16:25:52 +00001102 CGM.getDataLayout().getTypeAllocSize(constant->getType()))) {
John McCall60d33652011-03-08 09:11:50 +00001103 Builder.CreateMemSet(Loc, llvm::ConstantInt::get(Int8Ty, 0), SizeVal,
1104 alignment.getQuantity(), isVolatile);
Benjamin Kramer06d43682012-08-27 22:07:02 +00001105 // Zero and undef don't require a stores.
1106 if (!constant->isNullValue() && !isa<llvm::UndefValue>(constant)) {
John McCall60d33652011-03-08 09:11:50 +00001107 Loc = Builder.CreateBitCast(Loc, constant->getType()->getPointerTo());
1108 emitStoresForInitAfterMemset(constant, Loc, isVolatile, Builder);
Fariborz Jahanian20e1c7e2010-03-12 21:40:43 +00001109 }
John McCall60d33652011-03-08 09:11:50 +00001110 } else {
Eric Christophere1f54902011-08-23 22:38:00 +00001111 // Otherwise, create a temporary global with the initializer then
John McCall60d33652011-03-08 09:11:50 +00001112 // memcpy from the global to the alloca.
1113 std::string Name = GetStaticDeclName(*this, D, ".");
1114 llvm::GlobalVariable *GV =
1115 new llvm::GlobalVariable(CGM.getModule(), constant->getType(), true,
Eric Christopher736a9c22011-08-24 00:33:55 +00001116 llvm::GlobalValue::PrivateLinkage,
Hans Wennborg5e2d5de2012-06-23 11:51:46 +00001117 constant, Name);
John McCall60d33652011-03-08 09:11:50 +00001118 GV->setAlignment(alignment.getQuantity());
Eli Friedman460980d2011-05-27 22:32:55 +00001119 GV->setUnnamedAddr(true);
Eric Christophere1f54902011-08-23 22:38:00 +00001120
John McCall60d33652011-03-08 09:11:50 +00001121 llvm::Value *SrcPtr = GV;
1122 if (SrcPtr->getType() != BP)
Benjamin Kramer578faa82011-09-27 21:06:10 +00001123 SrcPtr = Builder.CreateBitCast(SrcPtr, BP);
John McCall60d33652011-03-08 09:11:50 +00001124
1125 Builder.CreateMemCpy(Loc, SrcPtr, SizeVal, alignment.getQuantity(),
1126 isVolatile);
1127 }
1128}
1129
1130/// Emit an expression as an initializer for a variable at the given
1131/// location. The expression is not necessarily the normal
1132/// initializer for the variable, and the address is not necessarily
1133/// its normal location.
1134///
1135/// \param init the initializing expression
1136/// \param var the variable to act as if we're initializing
1137/// \param loc the address to initialize; its type is a pointer
1138/// to the LLVM mapping of the variable's type
1139/// \param alignment the alignment of the address
1140/// \param capturedByInit true if the variable is a __block variable
1141/// whose address is potentially changed by the initializer
1142void CodeGenFunction::EmitExprAsInit(const Expr *init,
John McCallf85e1932011-06-15 23:02:42 +00001143 const ValueDecl *D,
John McCalla07398e2011-06-16 04:16:24 +00001144 LValue lvalue,
John McCall60d33652011-03-08 09:11:50 +00001145 bool capturedByInit) {
John McCallf85e1932011-06-15 23:02:42 +00001146 QualType type = D->getType();
John McCall60d33652011-03-08 09:11:50 +00001147
1148 if (type->isReferenceType()) {
John McCalla07398e2011-06-16 04:16:24 +00001149 RValue rvalue = EmitReferenceBindingToExpr(init, D);
Eric Christophere1f54902011-08-23 22:38:00 +00001150 if (capturedByInit)
John McCalla07398e2011-06-16 04:16:24 +00001151 drillIntoBlockVariable(*this, lvalue, cast<VarDecl>(D));
David Chisnall7a7ee302012-01-16 17:27:18 +00001152 EmitStoreThroughLValue(rvalue, lvalue, true);
John McCall9d232c82013-03-07 21:37:08 +00001153 return;
1154 }
1155 switch (getEvaluationKind(type)) {
1156 case TEK_Scalar:
John McCalla07398e2011-06-16 04:16:24 +00001157 EmitScalarInit(init, D, lvalue, capturedByInit);
John McCall9d232c82013-03-07 21:37:08 +00001158 return;
1159 case TEK_Complex: {
John McCall60d33652011-03-08 09:11:50 +00001160 ComplexPairTy complex = EmitComplexExpr(init);
John McCalla07398e2011-06-16 04:16:24 +00001161 if (capturedByInit)
1162 drillIntoBlockVariable(*this, lvalue, cast<VarDecl>(D));
John McCall9d232c82013-03-07 21:37:08 +00001163 EmitStoreOfComplex(complex, lvalue, /*init*/ true);
1164 return;
1165 }
1166 case TEK_Aggregate:
John McCall9eda3ab2013-03-07 21:37:17 +00001167 if (type->isAtomicType()) {
1168 EmitAtomicInit(const_cast<Expr*>(init), lvalue);
1169 } else {
1170 // TODO: how can we delay here if D is captured by its initializer?
1171 EmitAggExpr(init, AggValueSlot::forLValue(lvalue,
Chad Rosier649b4a12012-03-29 17:37:10 +00001172 AggValueSlot::IsDestructed,
John McCall410ffb22011-08-25 23:04:34 +00001173 AggValueSlot::DoesNotNeedGCBarriers,
Chad Rosier649b4a12012-03-29 17:37:10 +00001174 AggValueSlot::IsNotAliased));
John McCall9eda3ab2013-03-07 21:37:17 +00001175 }
Sebastian Redl972edf02012-02-19 16:03:09 +00001176 MaybeEmitStdInitializerListCleanup(lvalue.getAddress(), init);
John McCall9d232c82013-03-07 21:37:08 +00001177 return;
Fariborz Jahanian20e1c7e2010-03-12 21:40:43 +00001178 }
John McCall9d232c82013-03-07 21:37:08 +00001179 llvm_unreachable("bad evaluation kind");
John McCall34695852011-02-22 06:44:22 +00001180}
John McCallf1549f62010-07-06 01:34:17 +00001181
John McCallbdc4d802011-07-09 01:37:26 +00001182/// Enter a destroy cleanup for the given local variable.
1183void CodeGenFunction::emitAutoVarTypeCleanup(
1184 const CodeGenFunction::AutoVarEmission &emission,
1185 QualType::DestructionKind dtorKind) {
1186 assert(dtorKind != QualType::DK_none);
1187
1188 // Note that for __block variables, we want to destroy the
1189 // original stack object, not the possibly forwarded object.
1190 llvm::Value *addr = emission.getObjectAddress(*this);
1191
1192 const VarDecl *var = emission.Variable;
1193 QualType type = var->getType();
1194
1195 CleanupKind cleanupKind = NormalAndEHCleanup;
1196 CodeGenFunction::Destroyer *destroyer = 0;
1197
1198 switch (dtorKind) {
1199 case QualType::DK_none:
1200 llvm_unreachable("no cleanup for trivially-destructible variable");
1201
1202 case QualType::DK_cxx_destructor:
1203 // If there's an NRVO flag on the emission, we need a different
1204 // cleanup.
1205 if (emission.NRVOFlag) {
1206 assert(!type->isArrayType());
1207 CXXDestructorDecl *dtor = type->getAsCXXRecordDecl()->getDestructor();
1208 EHStack.pushCleanup<DestroyNRVOVariable>(cleanupKind, addr, dtor,
1209 emission.NRVOFlag);
1210 return;
1211 }
1212 break;
1213
1214 case QualType::DK_objc_strong_lifetime:
1215 // Suppress cleanups for pseudo-strong variables.
1216 if (var->isARCPseudoStrong()) return;
Eric Christophere1f54902011-08-23 22:38:00 +00001217
John McCallbdc4d802011-07-09 01:37:26 +00001218 // Otherwise, consider whether to use an EH cleanup or not.
1219 cleanupKind = getARCCleanupKind();
1220
1221 // Use the imprecise destroyer by default.
1222 if (!var->hasAttr<ObjCPreciseLifetimeAttr>())
1223 destroyer = CodeGenFunction::destroyARCStrongImprecise;
1224 break;
1225
1226 case QualType::DK_objc_weak_lifetime:
1227 break;
1228 }
1229
1230 // If we haven't chosen a more specific destroyer, use the default.
Peter Collingbourne516bbd42012-01-26 03:33:36 +00001231 if (!destroyer) destroyer = getDestroyer(dtorKind);
John McCall2673c682011-07-11 08:38:19 +00001232
Sylvestre Ledruf3477c12012-09-27 10:16:10 +00001233 // Use an EH cleanup in array destructors iff the destructor itself
John McCall2673c682011-07-11 08:38:19 +00001234 // is being pushed as an EH cleanup.
1235 bool useEHCleanup = (cleanupKind & EHCleanup);
1236 EHStack.pushCleanup<DestroyObject>(cleanupKind, addr, type, destroyer,
1237 useEHCleanup);
John McCallbdc4d802011-07-09 01:37:26 +00001238}
1239
John McCall34695852011-02-22 06:44:22 +00001240void CodeGenFunction::EmitAutoVarCleanups(const AutoVarEmission &emission) {
John McCall57b3b6a2011-02-22 07:16:58 +00001241 assert(emission.Variable && "emission was not valid!");
1242
John McCall34695852011-02-22 06:44:22 +00001243 // If this was emitted as a global constant, we're done.
1244 if (emission.wasEmittedAsGlobal()) return;
1245
John McCall38baeab2012-04-13 18:44:05 +00001246 // If we don't have an insertion point, we're done. Sema prevents
1247 // us from jumping into any of these scopes anyway.
1248 if (!HaveInsertPoint()) return;
1249
John McCall57b3b6a2011-02-22 07:16:58 +00001250 const VarDecl &D = *emission.Variable;
John McCall34695852011-02-22 06:44:22 +00001251
Nadav Rotem495cfa42013-03-23 06:43:35 +00001252 // Make sure we call @llvm.lifetime.end. This needs to happen
1253 // *last*, so the cleanup needs to be pushed *first*.
1254 if (emission.useLifetimeMarkers()) {
1255 EHStack.pushCleanup<CallLifetimeEnd>(NormalCleanup,
1256 emission.getAllocatedAddress(),
1257 emission.getSizeForLifetimeMarkers());
1258 }
1259
John McCallbdc4d802011-07-09 01:37:26 +00001260 // Check the type for a cleanup.
1261 if (QualType::DestructionKind dtorKind = D.getType().isDestructedType())
1262 emitAutoVarTypeCleanup(emission, dtorKind);
John McCallf85e1932011-06-15 23:02:42 +00001263
John McCall0c24c802011-06-24 23:21:27 +00001264 // In GC mode, honor objc_precise_lifetime.
David Blaikie4e4d0842012-03-11 07:00:24 +00001265 if (getLangOpts().getGC() != LangOptions::NonGC &&
John McCall0c24c802011-06-24 23:21:27 +00001266 D.hasAttr<ObjCPreciseLifetimeAttr>()) {
1267 EHStack.pushCleanup<ExtendGCLifetime>(NormalCleanup, &D);
1268 }
1269
John McCall34695852011-02-22 06:44:22 +00001270 // Handle the cleanup attribute.
Argyrios Kyrtzidis40b598e2009-06-30 02:34:44 +00001271 if (const CleanupAttr *CA = D.getAttr<CleanupAttr>()) {
Anders Carlsson69c68b72009-02-07 23:51:38 +00001272 const FunctionDecl *FD = CA->getFunctionDecl();
Mike Stump1eb44332009-09-09 15:08:12 +00001273
John McCall34695852011-02-22 06:44:22 +00001274 llvm::Constant *F = CGM.GetAddrOfFunction(FD);
Anders Carlsson69c68b72009-02-07 23:51:38 +00001275 assert(F && "Could not find function!");
Mike Stump1eb44332009-09-09 15:08:12 +00001276
John McCallde5d3c72012-02-17 03:33:10 +00001277 const CGFunctionInfo &Info = CGM.getTypes().arrangeFunctionDeclaration(FD);
John McCall34695852011-02-22 06:44:22 +00001278 EHStack.pushCleanup<CallCleanupFunction>(NormalAndEHCleanup, F, &Info, &D);
Anders Carlsson69c68b72009-02-07 23:51:38 +00001279 }
Mike Stump797b6322009-03-05 01:23:13 +00001280
John McCall34695852011-02-22 06:44:22 +00001281 // If this is a block variable, call _Block_object_destroy
1282 // (on the unforwarded address).
John McCall5af02db2011-03-31 01:59:53 +00001283 if (emission.IsByRef)
1284 enterByrefCleanup(emission);
Reid Spencer5f016e22007-07-11 17:01:13 +00001285}
1286
Peter Collingbourne516bbd42012-01-26 03:33:36 +00001287CodeGenFunction::Destroyer *
John McCallbdc4d802011-07-09 01:37:26 +00001288CodeGenFunction::getDestroyer(QualType::DestructionKind kind) {
1289 switch (kind) {
1290 case QualType::DK_none: llvm_unreachable("no destroyer for trivial dtor");
John McCall0850e8d2011-07-09 09:09:00 +00001291 case QualType::DK_cxx_destructor:
Peter Collingbourne516bbd42012-01-26 03:33:36 +00001292 return destroyCXXObject;
John McCall0850e8d2011-07-09 09:09:00 +00001293 case QualType::DK_objc_strong_lifetime:
Peter Collingbourne516bbd42012-01-26 03:33:36 +00001294 return destroyARCStrongPrecise;
John McCall0850e8d2011-07-09 09:09:00 +00001295 case QualType::DK_objc_weak_lifetime:
Peter Collingbourne516bbd42012-01-26 03:33:36 +00001296 return destroyARCWeak;
John McCallbdc4d802011-07-09 01:37:26 +00001297 }
Matt Beaumont-Gayba4be252012-01-27 00:46:27 +00001298 llvm_unreachable("Unknown DestructionKind");
John McCallbdc4d802011-07-09 01:37:26 +00001299}
1300
John McCall074cae02013-02-01 05:11:40 +00001301/// pushEHDestroy - Push the standard destructor for the given type as
1302/// an EH-only cleanup.
1303void CodeGenFunction::pushEHDestroy(QualType::DestructionKind dtorKind,
1304 llvm::Value *addr, QualType type) {
1305 assert(dtorKind && "cannot push destructor for trivial type");
1306 assert(needsEHCleanup(dtorKind));
1307
1308 pushDestroy(EHCleanup, addr, type, getDestroyer(dtorKind), true);
1309}
1310
1311/// pushDestroy - Push the standard destructor for the given type as
1312/// at least a normal cleanup.
John McCall9928c482011-07-12 16:41:08 +00001313void CodeGenFunction::pushDestroy(QualType::DestructionKind dtorKind,
1314 llvm::Value *addr, QualType type) {
1315 assert(dtorKind && "cannot push destructor for trivial type");
1316
1317 CleanupKind cleanupKind = getCleanupKind(dtorKind);
1318 pushDestroy(cleanupKind, addr, type, getDestroyer(dtorKind),
1319 cleanupKind & EHCleanup);
1320}
1321
John McCallbdc4d802011-07-09 01:37:26 +00001322void CodeGenFunction::pushDestroy(CleanupKind cleanupKind, llvm::Value *addr,
Peter Collingbourne516bbd42012-01-26 03:33:36 +00001323 QualType type, Destroyer *destroyer,
John McCall2673c682011-07-11 08:38:19 +00001324 bool useEHCleanupForArray) {
John McCall9928c482011-07-12 16:41:08 +00001325 pushFullExprCleanup<DestroyObject>(cleanupKind, addr, type,
1326 destroyer, useEHCleanupForArray);
John McCallbdc4d802011-07-09 01:37:26 +00001327}
1328
John McCall2673c682011-07-11 08:38:19 +00001329/// emitDestroy - Immediately perform the destruction of the given
1330/// object.
1331///
1332/// \param addr - the address of the object; a type*
1333/// \param type - the type of the object; if an array type, all
1334/// objects are destroyed in reverse order
1335/// \param destroyer - the function to call to destroy individual
1336/// elements
1337/// \param useEHCleanupForArray - whether an EH cleanup should be
1338/// used when destroying array elements, in case one of the
1339/// destructions throws an exception
John McCallbdc4d802011-07-09 01:37:26 +00001340void CodeGenFunction::emitDestroy(llvm::Value *addr, QualType type,
Peter Collingbourne516bbd42012-01-26 03:33:36 +00001341 Destroyer *destroyer,
John McCall2673c682011-07-11 08:38:19 +00001342 bool useEHCleanupForArray) {
John McCallbdc4d802011-07-09 01:37:26 +00001343 const ArrayType *arrayType = getContext().getAsArrayType(type);
1344 if (!arrayType)
1345 return destroyer(*this, addr, type);
1346
1347 llvm::Value *begin = addr;
1348 llvm::Value *length = emitArrayLength(arrayType, type, begin);
John McCallfbf780a2011-07-13 08:09:46 +00001349
1350 // Normally we have to check whether the array is zero-length.
1351 bool checkZeroLength = true;
1352
1353 // But if the array length is constant, we can suppress that.
1354 if (llvm::ConstantInt *constLength = dyn_cast<llvm::ConstantInt>(length)) {
1355 // ...and if it's constant zero, we can just skip the entire thing.
1356 if (constLength->isZero()) return;
1357 checkZeroLength = false;
1358 }
1359
John McCallbdc4d802011-07-09 01:37:26 +00001360 llvm::Value *end = Builder.CreateInBoundsGEP(begin, length);
John McCallfbf780a2011-07-13 08:09:46 +00001361 emitArrayDestroy(begin, end, type, destroyer,
1362 checkZeroLength, useEHCleanupForArray);
John McCallbdc4d802011-07-09 01:37:26 +00001363}
1364
John McCall2673c682011-07-11 08:38:19 +00001365/// emitArrayDestroy - Destroys all the elements of the given array,
1366/// beginning from last to first. The array cannot be zero-length.
1367///
1368/// \param begin - a type* denoting the first element of the array
1369/// \param end - a type* denoting one past the end of the array
1370/// \param type - the element type of the array
1371/// \param destroyer - the function to call to destroy elements
1372/// \param useEHCleanup - whether to push an EH cleanup to destroy
1373/// the remaining elements in case the destruction of a single
1374/// element throws
John McCallbdc4d802011-07-09 01:37:26 +00001375void CodeGenFunction::emitArrayDestroy(llvm::Value *begin,
1376 llvm::Value *end,
1377 QualType type,
Peter Collingbourne516bbd42012-01-26 03:33:36 +00001378 Destroyer *destroyer,
John McCallfbf780a2011-07-13 08:09:46 +00001379 bool checkZeroLength,
John McCall2673c682011-07-11 08:38:19 +00001380 bool useEHCleanup) {
John McCallbdc4d802011-07-09 01:37:26 +00001381 assert(!type->isArrayType());
1382
1383 // The basic structure here is a do-while loop, because we don't
1384 // need to check for the zero-element case.
1385 llvm::BasicBlock *bodyBB = createBasicBlock("arraydestroy.body");
1386 llvm::BasicBlock *doneBB = createBasicBlock("arraydestroy.done");
1387
John McCallfbf780a2011-07-13 08:09:46 +00001388 if (checkZeroLength) {
1389 llvm::Value *isEmpty = Builder.CreateICmpEQ(begin, end,
1390 "arraydestroy.isempty");
1391 Builder.CreateCondBr(isEmpty, doneBB, bodyBB);
1392 }
1393
John McCallbdc4d802011-07-09 01:37:26 +00001394 // Enter the loop body, making that address the current address.
1395 llvm::BasicBlock *entryBB = Builder.GetInsertBlock();
1396 EmitBlock(bodyBB);
1397 llvm::PHINode *elementPast =
1398 Builder.CreatePHI(begin->getType(), 2, "arraydestroy.elementPast");
1399 elementPast->addIncoming(end, entryBB);
1400
1401 // Shift the address back by one element.
1402 llvm::Value *negativeOne = llvm::ConstantInt::get(SizeTy, -1, true);
1403 llvm::Value *element = Builder.CreateInBoundsGEP(elementPast, negativeOne,
1404 "arraydestroy.element");
1405
John McCall2673c682011-07-11 08:38:19 +00001406 if (useEHCleanup)
1407 pushRegularPartialArrayCleanup(begin, element, type, destroyer);
1408
John McCallbdc4d802011-07-09 01:37:26 +00001409 // Perform the actual destruction there.
1410 destroyer(*this, element, type);
1411
John McCall2673c682011-07-11 08:38:19 +00001412 if (useEHCleanup)
1413 PopCleanupBlock();
1414
John McCallbdc4d802011-07-09 01:37:26 +00001415 // Check whether we've reached the end.
1416 llvm::Value *done = Builder.CreateICmpEQ(element, begin, "arraydestroy.done");
1417 Builder.CreateCondBr(done, doneBB, bodyBB);
1418 elementPast->addIncoming(element, Builder.GetInsertBlock());
1419
1420 // Done.
1421 EmitBlock(doneBB);
1422}
1423
John McCall2673c682011-07-11 08:38:19 +00001424/// Perform partial array destruction as if in an EH cleanup. Unlike
1425/// emitArrayDestroy, the element type here may still be an array type.
John McCall2673c682011-07-11 08:38:19 +00001426static void emitPartialArrayDestroy(CodeGenFunction &CGF,
1427 llvm::Value *begin, llvm::Value *end,
1428 QualType type,
Peter Collingbourne516bbd42012-01-26 03:33:36 +00001429 CodeGenFunction::Destroyer *destroyer) {
John McCall2673c682011-07-11 08:38:19 +00001430 // If the element type is itself an array, drill down.
John McCallfbf780a2011-07-13 08:09:46 +00001431 unsigned arrayDepth = 0;
John McCall2673c682011-07-11 08:38:19 +00001432 while (const ArrayType *arrayType = CGF.getContext().getAsArrayType(type)) {
1433 // VLAs don't require a GEP index to walk into.
1434 if (!isa<VariableArrayType>(arrayType))
John McCallfbf780a2011-07-13 08:09:46 +00001435 arrayDepth++;
John McCall2673c682011-07-11 08:38:19 +00001436 type = arrayType->getElementType();
1437 }
John McCallfbf780a2011-07-13 08:09:46 +00001438
1439 if (arrayDepth) {
1440 llvm::Value *zero = llvm::ConstantInt::get(CGF.SizeTy, arrayDepth+1);
1441
Chris Lattner5f9e2722011-07-23 10:55:15 +00001442 SmallVector<llvm::Value*,4> gepIndices(arrayDepth, zero);
Jay Foad0f6ac7c2011-07-22 08:16:57 +00001443 begin = CGF.Builder.CreateInBoundsGEP(begin, gepIndices, "pad.arraybegin");
1444 end = CGF.Builder.CreateInBoundsGEP(end, gepIndices, "pad.arrayend");
John McCall2673c682011-07-11 08:38:19 +00001445 }
1446
John McCallfbf780a2011-07-13 08:09:46 +00001447 // Destroy the array. We don't ever need an EH cleanup because we
1448 // assume that we're in an EH cleanup ourselves, so a throwing
1449 // destructor causes an immediate terminate.
1450 CGF.emitArrayDestroy(begin, end, type, destroyer,
1451 /*checkZeroLength*/ true, /*useEHCleanup*/ false);
John McCall2673c682011-07-11 08:38:19 +00001452}
1453
John McCallbdc4d802011-07-09 01:37:26 +00001454namespace {
John McCall2673c682011-07-11 08:38:19 +00001455 /// RegularPartialArrayDestroy - a cleanup which performs a partial
1456 /// array destroy where the end pointer is regularly determined and
1457 /// does not need to be loaded from a local.
1458 class RegularPartialArrayDestroy : public EHScopeStack::Cleanup {
1459 llvm::Value *ArrayBegin;
1460 llvm::Value *ArrayEnd;
1461 QualType ElementType;
Peter Collingbourne516bbd42012-01-26 03:33:36 +00001462 CodeGenFunction::Destroyer *Destroyer;
John McCall2673c682011-07-11 08:38:19 +00001463 public:
1464 RegularPartialArrayDestroy(llvm::Value *arrayBegin, llvm::Value *arrayEnd,
1465 QualType elementType,
1466 CodeGenFunction::Destroyer *destroyer)
1467 : ArrayBegin(arrayBegin), ArrayEnd(arrayEnd),
Peter Collingbourne516bbd42012-01-26 03:33:36 +00001468 ElementType(elementType), Destroyer(destroyer) {}
John McCall2673c682011-07-11 08:38:19 +00001469
John McCallad346f42011-07-12 20:27:29 +00001470 void Emit(CodeGenFunction &CGF, Flags flags) {
John McCall2673c682011-07-11 08:38:19 +00001471 emitPartialArrayDestroy(CGF, ArrayBegin, ArrayEnd,
1472 ElementType, Destroyer);
1473 }
1474 };
1475
1476 /// IrregularPartialArrayDestroy - a cleanup which performs a
1477 /// partial array destroy where the end pointer is irregularly
1478 /// determined and must be loaded from a local.
1479 class IrregularPartialArrayDestroy : public EHScopeStack::Cleanup {
John McCallbdc4d802011-07-09 01:37:26 +00001480 llvm::Value *ArrayBegin;
1481 llvm::Value *ArrayEndPointer;
1482 QualType ElementType;
Peter Collingbourne516bbd42012-01-26 03:33:36 +00001483 CodeGenFunction::Destroyer *Destroyer;
John McCallbdc4d802011-07-09 01:37:26 +00001484 public:
John McCall2673c682011-07-11 08:38:19 +00001485 IrregularPartialArrayDestroy(llvm::Value *arrayBegin,
1486 llvm::Value *arrayEndPointer,
1487 QualType elementType,
1488 CodeGenFunction::Destroyer *destroyer)
John McCallbdc4d802011-07-09 01:37:26 +00001489 : ArrayBegin(arrayBegin), ArrayEndPointer(arrayEndPointer),
Peter Collingbourne516bbd42012-01-26 03:33:36 +00001490 ElementType(elementType), Destroyer(destroyer) {}
John McCallbdc4d802011-07-09 01:37:26 +00001491
John McCallad346f42011-07-12 20:27:29 +00001492 void Emit(CodeGenFunction &CGF, Flags flags) {
John McCallbdc4d802011-07-09 01:37:26 +00001493 llvm::Value *arrayEnd = CGF.Builder.CreateLoad(ArrayEndPointer);
John McCall2673c682011-07-11 08:38:19 +00001494 emitPartialArrayDestroy(CGF, ArrayBegin, arrayEnd,
1495 ElementType, Destroyer);
John McCallbdc4d802011-07-09 01:37:26 +00001496 }
1497 };
1498}
1499
John McCall2673c682011-07-11 08:38:19 +00001500/// pushIrregularPartialArrayCleanup - Push an EH cleanup to destroy
John McCallbdc4d802011-07-09 01:37:26 +00001501/// already-constructed elements of the given array. The cleanup
John McCall2673c682011-07-11 08:38:19 +00001502/// may be popped with DeactivateCleanupBlock or PopCleanupBlock.
Eric Christophere1f54902011-08-23 22:38:00 +00001503///
John McCallbdc4d802011-07-09 01:37:26 +00001504/// \param elementType - the immediate element type of the array;
1505/// possibly still an array type
John McCall9928c482011-07-12 16:41:08 +00001506void CodeGenFunction::pushIrregularPartialArrayCleanup(llvm::Value *arrayBegin,
John McCall2673c682011-07-11 08:38:19 +00001507 llvm::Value *arrayEndPointer,
1508 QualType elementType,
Peter Collingbourne516bbd42012-01-26 03:33:36 +00001509 Destroyer *destroyer) {
John McCall9928c482011-07-12 16:41:08 +00001510 pushFullExprCleanup<IrregularPartialArrayDestroy>(EHCleanup,
1511 arrayBegin, arrayEndPointer,
Peter Collingbourne516bbd42012-01-26 03:33:36 +00001512 elementType, destroyer);
John McCall2673c682011-07-11 08:38:19 +00001513}
1514
1515/// pushRegularPartialArrayCleanup - Push an EH cleanup to destroy
1516/// already-constructed elements of the given array. The cleanup
1517/// may be popped with DeactivateCleanupBlock or PopCleanupBlock.
Eric Christophere1f54902011-08-23 22:38:00 +00001518///
John McCall2673c682011-07-11 08:38:19 +00001519/// \param elementType - the immediate element type of the array;
1520/// possibly still an array type
John McCall2673c682011-07-11 08:38:19 +00001521void CodeGenFunction::pushRegularPartialArrayCleanup(llvm::Value *arrayBegin,
1522 llvm::Value *arrayEnd,
1523 QualType elementType,
Peter Collingbourne516bbd42012-01-26 03:33:36 +00001524 Destroyer *destroyer) {
John McCall9928c482011-07-12 16:41:08 +00001525 pushFullExprCleanup<RegularPartialArrayDestroy>(EHCleanup,
John McCall2673c682011-07-11 08:38:19 +00001526 arrayBegin, arrayEnd,
Peter Collingbourne516bbd42012-01-26 03:33:36 +00001527 elementType, destroyer);
John McCallbdc4d802011-07-09 01:37:26 +00001528}
1529
Nadav Rotem495cfa42013-03-23 06:43:35 +00001530/// Lazily declare the @llvm.lifetime.start intrinsic.
1531llvm::Constant *CodeGenModule::getLLVMLifetimeStartFn() {
1532 if (LifetimeStartFn) return LifetimeStartFn;
1533 LifetimeStartFn = llvm::Intrinsic::getDeclaration(&getModule(),
1534 llvm::Intrinsic::lifetime_start);
1535 return LifetimeStartFn;
1536}
1537
1538/// Lazily declare the @llvm.lifetime.end intrinsic.
1539llvm::Constant *CodeGenModule::getLLVMLifetimeEndFn() {
1540 if (LifetimeEndFn) return LifetimeEndFn;
1541 LifetimeEndFn = llvm::Intrinsic::getDeclaration(&getModule(),
1542 llvm::Intrinsic::lifetime_end);
1543 return LifetimeEndFn;
1544}
1545
John McCallf85e1932011-06-15 23:02:42 +00001546namespace {
1547 /// A cleanup to perform a release of an object at the end of a
1548 /// function. This is used to balance out the incoming +1 of a
1549 /// ns_consumed argument when we can't reasonably do that just by
1550 /// not doing the initial retain for a __block argument.
1551 struct ConsumeARCParameter : EHScopeStack::Cleanup {
John McCall5b07e802013-03-13 03:10:54 +00001552 ConsumeARCParameter(llvm::Value *param,
1553 ARCPreciseLifetime_t precise)
1554 : Param(param), Precise(precise) {}
John McCallf85e1932011-06-15 23:02:42 +00001555
1556 llvm::Value *Param;
John McCall5b07e802013-03-13 03:10:54 +00001557 ARCPreciseLifetime_t Precise;
John McCallf85e1932011-06-15 23:02:42 +00001558
John McCallad346f42011-07-12 20:27:29 +00001559 void Emit(CodeGenFunction &CGF, Flags flags) {
John McCall5b07e802013-03-13 03:10:54 +00001560 CGF.EmitARCRelease(Param, Precise);
John McCallf85e1932011-06-15 23:02:42 +00001561 }
1562 };
1563}
1564
Mike Stump1eb44332009-09-09 15:08:12 +00001565/// Emit an alloca (or GlobalValue depending on target)
Chris Lattner2621fd12008-05-08 05:58:21 +00001566/// for the specified parameter and set up LocalDeclMap.
Devang Patel093ac462011-03-03 20:13:15 +00001567void CodeGenFunction::EmitParmDecl(const VarDecl &D, llvm::Value *Arg,
1568 unsigned ArgNo) {
Daniel Dunbarb7ec2462008-08-16 03:19:19 +00001569 // FIXME: Why isn't ImplicitParamDecl a ParmVarDecl?
Sanjiv Gupta31fc07d2008-10-31 09:52:39 +00001570 assert((isa<ParmVarDecl>(D) || isa<ImplicitParamDecl>(D)) &&
Daniel Dunbarb7ec2462008-08-16 03:19:19 +00001571 "Invalid argument to EmitParmDecl");
John McCall8178df32011-02-22 22:38:33 +00001572
1573 Arg->setName(D.getName());
1574
Adrian Prantl836e7c92013-03-14 17:53:33 +00001575 QualType Ty = D.getType();
1576
John McCall8178df32011-02-22 22:38:33 +00001577 // Use better IR generation for certain implicit parameters.
1578 if (isa<ImplicitParamDecl>(D)) {
1579 // The only implicit argument a block has is its literal.
1580 if (BlockInfo) {
1581 LocalDeclMap[&D] = Arg;
Adrian Prantl836e7c92013-03-14 17:53:33 +00001582 llvm::Value *LocalAddr = 0;
1583 if (CGM.getCodeGenOpts().OptimizationLevel == 0) {
Adrian Prantl9b97adf2013-03-29 19:20:35 +00001584 // Allocate a stack slot to let the debug info survive the RA.
Adrian Prantl836e7c92013-03-14 17:53:33 +00001585 llvm::AllocaInst *Alloc = CreateTempAlloca(ConvertTypeForMem(Ty),
1586 D.getName() + ".addr");
1587 Alloc->setAlignment(getContext().getDeclAlign(&D).getQuantity());
1588 LValue lv = MakeAddrLValue(Alloc, Ty, getContext().getDeclAlign(&D));
1589 EmitStoreOfScalar(Arg, lv, /* isInitialization */ true);
1590 LocalAddr = Builder.CreateLoad(Alloc);
1591 }
John McCall8178df32011-02-22 22:38:33 +00001592
1593 if (CGDebugInfo *DI = getDebugInfo()) {
Douglas Gregor4cdad312012-10-23 20:05:01 +00001594 if (CGM.getCodeGenOpts().getDebugInfo()
1595 >= CodeGenOptions::LimitedDebugInfo) {
Alexey Samsonovfd00eec2012-05-04 07:39:27 +00001596 DI->setLocation(D.getLocation());
Adrian Prantl836e7c92013-03-14 17:53:33 +00001597 DI->EmitDeclareOfBlockLiteralArgVariable(*BlockInfo, Arg, LocalAddr, Builder);
Alexey Samsonovfd00eec2012-05-04 07:39:27 +00001598 }
John McCall8178df32011-02-22 22:38:33 +00001599 }
1600
1601 return;
1602 }
1603 }
1604
Reid Spencer5f016e22007-07-11 17:01:13 +00001605 llvm::Value *DeclPtr;
Daniel Dunbare86bcf02010-02-08 22:53:07 +00001606 // If this is an aggregate or variable sized value, reuse the input pointer.
1607 if (!Ty->isConstantSizeType() ||
John McCall9d232c82013-03-07 21:37:08 +00001608 !CodeGenFunction::hasScalarEvaluationKind(Ty)) {
Reid Spencer5f016e22007-07-11 17:01:13 +00001609 DeclPtr = Arg;
Reid Spencer5f016e22007-07-11 17:01:13 +00001610 } else {
Daniel Dunbare86bcf02010-02-08 22:53:07 +00001611 // Otherwise, create a temporary to hold the value.
Eli Friedmanddfb8d12011-11-03 20:31:28 +00001612 llvm::AllocaInst *Alloc = CreateTempAlloca(ConvertTypeForMem(Ty),
1613 D.getName() + ".addr");
Fariborz Jahanian41a6a3e2013-02-21 00:40:10 +00001614 CharUnits Align = getContext().getDeclAlign(&D);
1615 Alloc->setAlignment(Align.getQuantity());
Eli Friedmanddfb8d12011-11-03 20:31:28 +00001616 DeclPtr = Alloc;
Mike Stump1eb44332009-09-09 15:08:12 +00001617
John McCallf85e1932011-06-15 23:02:42 +00001618 bool doStore = true;
1619
1620 Qualifiers qs = Ty.getQualifiers();
Fariborz Jahanian41a6a3e2013-02-21 00:40:10 +00001621 LValue lv = MakeAddrLValue(DeclPtr, Ty, Align);
John McCallf85e1932011-06-15 23:02:42 +00001622 if (Qualifiers::ObjCLifetime lt = qs.getObjCLifetime()) {
1623 // We honor __attribute__((ns_consumed)) for types with lifetime.
1624 // For __strong, it's handled by just skipping the initial retain;
1625 // otherwise we have to balance out the initial +1 with an extra
1626 // cleanup to do the release at the end of the function.
1627 bool isConsumed = D.hasAttr<NSConsumedAttr>();
1628
1629 // 'self' is always formally __strong, but if this is not an
1630 // init method then we don't want to retain it.
John McCall7acddac2011-06-17 06:42:21 +00001631 if (D.isARCPseudoStrong()) {
John McCallf85e1932011-06-15 23:02:42 +00001632 const ObjCMethodDecl *method = cast<ObjCMethodDecl>(CurCodeDecl);
1633 assert(&D == method->getSelfDecl());
John McCall7acddac2011-06-17 06:42:21 +00001634 assert(lt == Qualifiers::OCL_Strong);
1635 assert(qs.hasConst());
John McCallf85e1932011-06-15 23:02:42 +00001636 assert(method->getMethodFamily() != OMF_init);
John McCall175d6592011-06-15 23:40:09 +00001637 (void) method;
John McCallf85e1932011-06-15 23:02:42 +00001638 lt = Qualifiers::OCL_ExplicitNone;
1639 }
1640
1641 if (lt == Qualifiers::OCL_Strong) {
Fariborz Jahanian41a6a3e2013-02-21 00:40:10 +00001642 if (!isConsumed) {
1643 if (CGM.getCodeGenOpts().OptimizationLevel == 0) {
1644 // use objc_storeStrong(&dest, value) for retaining the
1645 // object. But first, store a null into 'dest' because
1646 // objc_storeStrong attempts to release its old value.
1647 llvm::Value * Null = CGM.EmitNullConstant(D.getType());
1648 EmitStoreOfScalar(Null, lv, /* isInitialization */ true);
1649 EmitARCStoreStrongCall(lv.getAddress(), Arg, true);
1650 doStore = false;
1651 }
1652 else
John McCallf85e1932011-06-15 23:02:42 +00001653 // Don't use objc_retainBlock for block pointers, because we
1654 // don't want to Block_copy something just because we got it
1655 // as a parameter.
Fariborz Jahanian41a6a3e2013-02-21 00:40:10 +00001656 Arg = EmitARCRetainNonBlock(Arg);
1657 }
John McCallf85e1932011-06-15 23:02:42 +00001658 } else {
1659 // Push the cleanup for a consumed parameter.
John McCall5b07e802013-03-13 03:10:54 +00001660 if (isConsumed) {
1661 ARCPreciseLifetime_t precise = (D.hasAttr<ObjCPreciseLifetimeAttr>()
1662 ? ARCPreciseLifetime : ARCImpreciseLifetime);
1663 EHStack.pushCleanup<ConsumeARCParameter>(getARCCleanupKind(), Arg,
1664 precise);
1665 }
John McCallf85e1932011-06-15 23:02:42 +00001666
1667 if (lt == Qualifiers::OCL_Weak) {
1668 EmitARCInitWeak(DeclPtr, Arg);
Chad Rosier7acebfb2012-02-18 01:20:35 +00001669 doStore = false; // The weak init is a store, no need to do two.
John McCallf85e1932011-06-15 23:02:42 +00001670 }
1671 }
1672
1673 // Enter the cleanup scope.
1674 EmitAutoVarWithLifetime(*this, D, DeclPtr, lt);
1675 }
1676
Daniel Dunbare86bcf02010-02-08 22:53:07 +00001677 // Store the initial value into the alloca.
Fariborz Jahanian41a6a3e2013-02-21 00:40:10 +00001678 if (doStore)
David Chisnall7a7ee302012-01-16 17:27:18 +00001679 EmitStoreOfScalar(Arg, lv, /* isInitialization */ true);
Reid Spencer5f016e22007-07-11 17:01:13 +00001680 }
1681
1682 llvm::Value *&DMEntry = LocalDeclMap[&D];
1683 assert(DMEntry == 0 && "Decl already exists in localdeclmap!");
1684 DMEntry = DeclPtr;
Sanjiv Guptacc9b1632008-05-30 10:30:31 +00001685
1686 // Emit debug info for param declaration.
Alexey Samsonovfd00eec2012-05-04 07:39:27 +00001687 if (CGDebugInfo *DI = getDebugInfo()) {
Douglas Gregor4cdad312012-10-23 20:05:01 +00001688 if (CGM.getCodeGenOpts().getDebugInfo()
1689 >= CodeGenOptions::LimitedDebugInfo) {
Alexey Samsonovfd00eec2012-05-04 07:39:27 +00001690 DI->EmitDeclareOfArgVariable(&D, DeclPtr, ArgNo, Builder);
1691 }
1692 }
Julien Lerouge77f68bb2011-09-09 22:41:49 +00001693
1694 if (D.hasAttr<AnnotateAttr>())
1695 EmitVarAnnotations(&D, DeclPtr);
Reid Spencer5f016e22007-07-11 17:01:13 +00001696}