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Avoid adding some decls to DeferredDeclsToEmit.

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Before this patch GetOrCreateLLVMFunction would add a decl to
DeferredDeclsToEmit even when it was being called by the function trying to
emit that decl.

llvm-svn: 196753
This commit is contained in:
Rafael Espindola
2013-12-09 04:29:47 +00:00
parent 048f90cc04
commit 94abb8ffed
4 changed files with 90 additions and 75 deletions
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119
clang/lib/CodeGen/CodeGenModule.cpp
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@@ -1374,6 +1374,7 @@ llvm::Constant *
CodeGenModule::GetOrCreateLLVMFunction(StringRef MangledName,
llvm::Type *Ty,
GlobalDecl GD, bool ForVTable,
bool DontDefer,
llvm::AttributeSet ExtraAttrs) {
const Decl *D = GD.getDecl();
@@ -1393,14 +1394,6 @@ CodeGenModule::GetOrCreateLLVMFunction(StringRef MangledName,
return llvm::ConstantExpr::getBitCast(Entry, Ty->getPointerTo());
}
// All MSVC dtors other than the base dtor are linkonce_odr and delegate to
// each other bottoming out with the base dtor. Therefore we emit non-base
// dtors on usage, even if there is no dtor definition in the TU.
if (D && isa<CXXDestructorDecl>(D) &&
getCXXABI().useThunkForDtorVariant(cast<CXXDestructorDecl>(D),
GD.getDtorType()))
DeferredDeclsToEmit.push_back(GD);
// This function doesn't have a complete type (for example, the return
// type is an incomplete struct). Use a fake type instead, and make
// sure not to try to set attributes.
@@ -1428,50 +1421,64 @@ CodeGenModule::GetOrCreateLLVMFunction(StringRef MangledName,
B));
}
// This is the first use or definition of a mangled name. If there is a
// deferred decl with this name, remember that we need to emit it at the end
// of the file.
llvm::StringMap<GlobalDecl>::iterator DDI = DeferredDecls.find(MangledName);
if (DDI != DeferredDecls.end()) {
// Move the potentially referenced deferred decl to the DeferredDeclsToEmit
// list, and remove it from DeferredDecls (since we don't need it anymore).
DeferredDeclsToEmit.push_back(DDI->second);
DeferredDecls.erase(DDI);
if (!DontDefer) {
// All MSVC dtors other than the base dtor are linkonce_odr and delegate to
// each other bottoming out with the base dtor. Therefore we emit non-base
// dtors on usage, even if there is no dtor definition in the TU.
if (D && isa<CXXDestructorDecl>(D) &&
getCXXABI().useThunkForDtorVariant(cast<CXXDestructorDecl>(D),
GD.getDtorType()))
DeferredDeclsToEmit.push_back(GD);
// Otherwise, if this is a sized deallocation function, emit a weak definition
// for it at the end of the translation unit.
} else if (D && cast<FunctionDecl>(D)
->getCorrespondingUnsizedGlobalDeallocationFunction()) {
DeferredDeclsToEmit.push_back(GD);
// This is the first use or definition of a mangled name. If there is a
// deferred decl with this name, remember that we need to emit it at the end
// of the file.
llvm::StringMap<GlobalDecl>::iterator DDI = DeferredDecls.find(MangledName);
if (DDI != DeferredDecls.end()) {
// Move the potentially referenced deferred decl to the
// DeferredDeclsToEmit list, and remove it from DeferredDecls (since we
// don't need it anymore).
DeferredDeclsToEmit.push_back(DDI->second);
DeferredDecls.erase(DDI);
// Otherwise, there are cases we have to worry about where we're
// using a declaration for which we must emit a definition but where
// we might not find a top-level definition:
// - member functions defined inline in their classes
// - friend functions defined inline in some class
// - special member functions with implicit definitions
// If we ever change our AST traversal to walk into class methods,
// this will be unnecessary.
//
// We also don't emit a definition for a function if it's going to be an entry
// in a vtable, unless it's already marked as used.
} else if (getLangOpts().CPlusPlus && D) {
// Look for a declaration that's lexically in a record.
const FunctionDecl *FD = cast<FunctionDecl>(D);
FD = FD->getMostRecentDecl();
do {
if (isa<CXXRecordDecl>(FD->getLexicalDeclContext())) {
if (FD->isImplicit() && !ForVTable) {
assert(FD->isUsed() && "Sema didn't mark implicit function as used!");
DeferredDeclsToEmit.push_back(GD.getWithDecl(FD));
break;
} else if (FD->doesThisDeclarationHaveABody()) {
DeferredDeclsToEmit.push_back(GD.getWithDecl(FD));
break;
// Otherwise, if this is a sized deallocation function, emit a weak
// definition
// for it at the end of the translation unit.
} else if (D && cast<FunctionDecl>(D)
->getCorrespondingUnsizedGlobalDeallocationFunction()) {
DeferredDeclsToEmit.push_back(GD);
// Otherwise, there are cases we have to worry about where we're
// using a declaration for which we must emit a definition but where
// we might not find a top-level definition:
// - member functions defined inline in their classes
// - friend functions defined inline in some class
// - special member functions with implicit definitions
// If we ever change our AST traversal to walk into class methods,
// this will be unnecessary.
//
// We also don't emit a definition for a function if it's going to be an
// entry
// in a vtable, unless it's already marked as used.
} else if (getLangOpts().CPlusPlus && D) {
// Look for a declaration that's lexically in a record.
const FunctionDecl *FD = cast<FunctionDecl>(D);
FD = FD->getMostRecentDecl();
do {
if (isa<CXXRecordDecl>(FD->getLexicalDeclContext())) {
if (FD->isImplicit() && !ForVTable) {
assert(FD->isUsed() &&
"Sema didn't mark implicit function as used!");
DeferredDeclsToEmit.push_back(GD.getWithDecl(FD));
break;
} else if (FD->doesThisDeclarationHaveABody()) {
DeferredDeclsToEmit.push_back(GD.getWithDecl(FD));
break;
}
}
}
FD = FD->getPreviousDecl();
} while (FD);
FD = FD->getPreviousDecl();
} while (FD);
}
}
// Make sure the result is of the requested type.
@@ -1489,13 +1496,14 @@ CodeGenModule::GetOrCreateLLVMFunction(StringRef MangledName,
/// create it (this occurs when we see a definition of the function).
llvm::Constant *CodeGenModule::GetAddrOfFunction(GlobalDecl GD,
llvm::Type *Ty,
bool ForVTable) {
bool ForVTable,
bool DontDefer) {
// If there was no specific requested type, just convert it now.
if (!Ty)
Ty = getTypes().ConvertType(cast<ValueDecl>(GD.getDecl())->getType());
StringRef MangledName = getMangledName(GD);
return GetOrCreateLLVMFunction(MangledName, Ty, GD, ForVTable);
return GetOrCreateLLVMFunction(MangledName, Ty, GD, ForVTable, DontDefer);
}
/// CreateRuntimeFunction - Create a new runtime function with the specified
@@ -1504,9 +1512,9 @@ llvm::Constant *
CodeGenModule::CreateRuntimeFunction(llvm::FunctionType *FTy,
StringRef Name,
llvm::AttributeSet ExtraAttrs) {
llvm::Constant *C
= GetOrCreateLLVMFunction(Name, FTy, GlobalDecl(), /*ForVTable=*/false,
ExtraAttrs);
llvm::Constant *C =
GetOrCreateLLVMFunction(Name, FTy, GlobalDecl(), /*ForVTable=*/false,
/*DontDefer=*/false, ExtraAttrs);
if (llvm::Function *F = dyn_cast<llvm::Function>(C))
if (F->empty())
F->setCallingConv(getRuntimeCC());
@@ -2090,7 +2098,8 @@ void CodeGenModule::EmitGlobalFunctionDefinition(GlobalDecl GD) {
llvm::FunctionType *Ty = getTypes().GetFunctionType(FI);
// Get or create the prototype for the function.
llvm::Constant *Entry = GetAddrOfFunction(GD, Ty);
llvm::Constant *Entry =
GetAddrOfFunction(GD, Ty, /*ForVTable=*/false, /*DontDefer*/ true);
// Strip off a bitcast if we got one back.
if (llvm::ConstantExpr *CE = dyn_cast<llvm::ConstantExpr>(Entry)) {