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Remove useGlobalsForAutomaticVariables. 

It is unused since pic support went away.

llvm-svn: 178055
This commit is contained in:
Rafael Espindola 2013-03-26 18:41:47 +00:00
parent 6a476082a6
commit 609f5d98d4
3 changed files with 75 additions and 90 deletions
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2
clang/include/clang/Basic/TargetInfo.h
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@ -571,8 +571,6 @@ public:
/// either; the entire thing is pretty badly mangled.
virtual bool hasProtectedVisibility() const { return true; }
virtual bool useGlobalsForAutomaticVariables() const { return false; }
/// \brief Return the section to use for CFString literals, or 0 if no
/// special section is used.
virtual const char *getCFStringSection() const {

160
clang/lib/CodeGen/CGDecl.cpp
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@ -827,99 +827,91 @@ CodeGenFunction::EmitAutoVarAlloca(const VarDecl &D) {
llvm::Value *DeclPtr;
if (Ty->isConstantSizeType()) {
if (!Target.useGlobalsForAutomaticVariables()) {
bool NRVO = getLangOpts().ElideConstructors &&
D.isNRVOVariable();
bool NRVO = getLangOpts().ElideConstructors &&
D.isNRVOVariable();
// If this value is a POD array or struct with a statically
// determinable constant initializer, there are optimizations we can do.
//
// TODO: We should constant-evaluate the initializer of any variable,
// as long as it is initialized by a constant expression. Currently,
// isConstantInitializer produces wrong answers for structs with
// reference or bitfield members, and a few other cases, and checking
// for POD-ness protects us from some of these.
if (D.getInit() &&
(Ty->isArrayType() || Ty->isRecordType()) &&
(Ty.isPODType(getContext()) ||
getContext().getBaseElementType(Ty)->isObjCObjectPointerType()) &&
D.getInit()->isConstantInitializer(getContext(), false)) {
// If this value is a POD array or struct with a statically
// determinable constant initializer, there are optimizations we can do.
//
// TODO: We should constant-evaluate the initializer of any variable,
// as long as it is initialized by a constant expression. Currently,
// isConstantInitializer produces wrong answers for structs with
// reference or bitfield members, and a few other cases, and checking
// for POD-ness protects us from some of these.
if (D.getInit() &&
(Ty->isArrayType() || Ty->isRecordType()) &&
(Ty.isPODType(getContext()) ||
getContext().getBaseElementType(Ty)->isObjCObjectPointerType()) &&
D.getInit()->isConstantInitializer(getContext(), false)) {
// If the variable's a const type, and it's neither an NRVO
// candidate nor a __block variable and has no mutable members,
// emit it as a global instead.
if (CGM.getCodeGenOpts().MergeAllConstants && !NRVO && !isByRef &&
CGM.isTypeConstant(Ty, true)) {
EmitStaticVarDecl(D, llvm::GlobalValue::InternalLinkage);
// If the variable's a const type, and it's neither an NRVO
// candidate nor a __block variable and has no mutable members,
// emit it as a global instead.
if (CGM.getCodeGenOpts().MergeAllConstants && !NRVO && !isByRef &&
CGM.isTypeConstant(Ty, true)) {
EmitStaticVarDecl(D, llvm::GlobalValue::InternalLinkage);
emission.Address = 0; // signal this condition to later callbacks
assert(emission.wasEmittedAsGlobal());
return emission;
}
// Otherwise, tell the initialization code that we're in this case.
emission.IsConstantAggregate = true;
emission.Address = 0; // signal this condition to later callbacks
assert(emission.wasEmittedAsGlobal());
return emission;
}
// A normal fixed sized variable becomes an alloca in the entry block,
// unless it's an NRVO variable.
llvm::Type *LTy = ConvertTypeForMem(Ty);
// Otherwise, tell the initialization code that we're in this case.
emission.IsConstantAggregate = true;
}
if (NRVO) {
// The named return value optimization: allocate this variable in the
// return slot, so that we can elide the copy when returning this
// variable (C++0x [class.copy]p34).
DeclPtr = ReturnValue;
// A normal fixed sized variable becomes an alloca in the entry block,
// unless it's an NRVO variable.
llvm::Type *LTy = ConvertTypeForMem(Ty);
if (const RecordType *RecordTy = Ty->getAs<RecordType>()) {
if (!cast<CXXRecordDecl>(RecordTy->getDecl())->hasTrivialDestructor()) {
// Create a flag that is used to indicate when the NRVO was applied
// to this variable. Set it to zero to indicate that NRVO was not
// applied.
llvm::Value *Zero = Builder.getFalse();
llvm::Value *NRVOFlag = CreateTempAlloca(Zero->getType(), "nrvo");
EnsureInsertPoint();
Builder.CreateStore(Zero, NRVOFlag);
if (NRVO) {
// The named return value optimization: allocate this variable in the
// return slot, so that we can elide the copy when returning this
// variable (C++0x [class.copy]p34).
DeclPtr = ReturnValue;
// Record the NRVO flag for this variable.
NRVOFlags[&D] = NRVOFlag;
emission.NRVOFlag = NRVOFlag;
}
}
} else {
if (isByRef)
LTy = BuildByRefType(&D);
if (const RecordType *RecordTy = Ty->getAs<RecordType>()) {
if (!cast<CXXRecordDecl>(RecordTy->getDecl())->hasTrivialDestructor()) {
// Create a flag that is used to indicate when the NRVO was applied
// to this variable. Set it to zero to indicate that NRVO was not
// applied.
llvm::Value *Zero = Builder.getFalse();
llvm::Value *NRVOFlag = CreateTempAlloca(Zero->getType(), "nrvo");
EnsureInsertPoint();
Builder.CreateStore(Zero, NRVOFlag);
llvm::AllocaInst *Alloc = CreateTempAlloca(LTy);
Alloc->setName(D.getName());
CharUnits allocaAlignment = alignment;
if (isByRef)
allocaAlignment = std::max(allocaAlignment,
getContext().toCharUnitsFromBits(Target.getPointerAlign(0)));
Alloc->setAlignment(allocaAlignment.getQuantity());
DeclPtr = Alloc;
// Emit a lifetime intrinsic if meaningful. There's no point
// in doing this if we don't have a valid insertion point (?).
uint64_t size = CGM.getDataLayout().getTypeAllocSize(LTy);
if (HaveInsertPoint() && shouldUseLifetimeMarkers(*this, D, size)) {
llvm::Value *sizeV = llvm::ConstantInt::get(Int64Ty, size);
emission.SizeForLifetimeMarkers = sizeV;
llvm::Value *castAddr = Builder.CreateBitCast(Alloc, Int8PtrTy);
Builder.CreateCall2(CGM.getLLVMLifetimeStartFn(), sizeV, castAddr)
->setDoesNotThrow();
} else {
assert(!emission.useLifetimeMarkers());
// Record the NRVO flag for this variable.
NRVOFlags[&D] = NRVOFlag;
emission.NRVOFlag = NRVOFlag;
}
}
} else {
// Targets that don't support recursion emit locals as globals.
const char *Class =
D.getStorageClass() == SC_Register ? ".reg." : ".auto.";
DeclPtr = CreateStaticVarDecl(D, Class,
llvm::GlobalValue::InternalLinkage);
if (isByRef)
LTy = BuildByRefType(&D);
llvm::AllocaInst *Alloc = CreateTempAlloca(LTy);
Alloc->setName(D.getName());
CharUnits allocaAlignment = alignment;
if (isByRef)
allocaAlignment = std::max(allocaAlignment,
getContext().toCharUnitsFromBits(Target.getPointerAlign(0)));
Alloc->setAlignment(allocaAlignment.getQuantity());
DeclPtr = Alloc;
// Emit a lifetime intrinsic if meaningful. There's no point
// in doing this if we don't have a valid insertion point (?).
uint64_t size = CGM.getDataLayout().getTypeAllocSize(LTy);
if (HaveInsertPoint() && shouldUseLifetimeMarkers(*this, D, size)) {
llvm::Value *sizeV = llvm::ConstantInt::get(Int64Ty, size);
emission.SizeForLifetimeMarkers = sizeV;
llvm::Value *castAddr = Builder.CreateBitCast(Alloc, Int8PtrTy);
Builder.CreateCall2(CGM.getLLVMLifetimeStartFn(), sizeV, castAddr)
->setDoesNotThrow();
} else {
assert(!emission.useLifetimeMarkers());
}
}
} else {
EnsureInsertPoint();
@ -964,11 +956,7 @@ CodeGenFunction::EmitAutoVarAlloca(const VarDecl &D) {
if (CGM.getCodeGenOpts().getDebugInfo()
>= CodeGenOptions::LimitedDebugInfo) {
DI->setLocation(D.getLocation());
if (Target.useGlobalsForAutomaticVariables()) {
DI->EmitGlobalVariable(static_cast<llvm::GlobalVariable *>(DeclPtr),
&D);
} else
DI->EmitDeclareOfAutoVariable(&D, DeclPtr, Builder);
DI->EmitDeclareOfAutoVariable(&D, DeclPtr, Builder);
}
}

3
clang/lib/CodeGen/CGStmt.cpp
View File

@ -794,8 +794,7 @@ void CodeGenFunction::EmitReturnStmt(const ReturnStmt &S) {
// FIXME: Clean this up by using an LValue for ReturnTemp,
// EmitStoreThroughLValue, and EmitAnyExpr.
if (S.getNRVOCandidate() && S.getNRVOCandidate()->isNRVOVariable() &&
!Target.useGlobalsForAutomaticVariables()) {
if (S.getNRVOCandidate() && S.getNRVOCandidate()->isNRVOVariable()) {
// Apply the named return value optimization for this return statement,
// which means doing nothing: the appropriate result has already been
// constructed into the NRVO variable.