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authorEli Bendersky <eliben@chromium.org>2013-07-15 16:08:08 -0700
committerEli Bendersky <eliben@chromium.org>2013-07-15 16:08:08 -0700
commite789858899a7b36caf11b371a97411a1582a482b (patch)
treee8c28b178b32010f73b477b3c65b5ff74437530c /lib/CodeGen/ItaniumCXXABI.cpp
parent99a5501f5ae5b75017dfc386d4abf648234e85df (diff)
parent20c7d45a4da9f58ad805ad1d37f92fe7dc232ec8 (diff)
Merge commit '20c7d45a4da9f58ad805ad1d37f92fe7dc232ec8'
Conflicts: lib/CodeGen/ItaniumCXXABI.cpp
Diffstat (limited to 'lib/CodeGen/ItaniumCXXABI.cpp')
-rw-r--r--lib/CodeGen/ItaniumCXXABI.cpp220
1 files changed, 185 insertions, 35 deletions
diff --git a/lib/CodeGen/ItaniumCXXABI.cpp b/lib/CodeGen/ItaniumCXXABI.cpp
index b314fd6a39..9ab3f8c3ee 100644
--- a/lib/CodeGen/ItaniumCXXABI.cpp
+++ b/lib/CodeGen/ItaniumCXXABI.cpp
@@ -39,7 +39,6 @@ private:
protected:
bool UseARMMethodPtrABI;
bool UseARMGuardVarABI;
-
// It's a little silly for us to cache this.
llvm::IntegerType *getPtrDiffTy() {
if (!PtrDiffTy) {
@@ -117,7 +116,7 @@ public:
void EmitInstanceFunctionProlog(CodeGenFunction &CGF);
- void EmitConstructorCall(CodeGenFunction &CGF,
+ llvm::Value *EmitConstructorCall(CodeGenFunction &CGF,
const CXXConstructorDecl *D,
CXXCtorType Type, bool ForVirtualBase,
bool Delegating,
@@ -147,8 +146,16 @@ public:
void EmitGuardedInit(CodeGenFunction &CGF, const VarDecl &D,
llvm::GlobalVariable *DeclPtr, bool PerformInit);
- void registerGlobalDtor(CodeGenFunction &CGF, llvm::Constant *dtor,
- llvm::Constant *addr);
+ void registerGlobalDtor(CodeGenFunction &CGF, const VarDecl &D,
+ llvm::Constant *dtor, llvm::Constant *addr);
+
+ llvm::Function *getOrCreateThreadLocalWrapper(const VarDecl *VD,
+ llvm::GlobalVariable *Var);
+ void EmitThreadLocalInitFuncs(
+ llvm::ArrayRef<std::pair<const VarDecl *, llvm::GlobalVariable *> > Decls,
+ llvm::Function *InitFunc);
+ LValue EmitThreadLocalDeclRefExpr(CodeGenFunction &CGF,
+ const DeclRefExpr *DRE);
};
class ARMCXXABI : public ItaniumCXXABI {
@@ -184,11 +191,11 @@ public:
llvm::Value *readArrayCookieImpl(CodeGenFunction &CGF, llvm::Value *allocPtr,
CharUnits cookieSize);
-private:
/// \brief Returns true if the given instance method is one of the
/// kinds that the ARM ABI says returns 'this'.
- static bool HasThisReturn(GlobalDecl GD) {
- const CXXMethodDecl *MD = cast<CXXMethodDecl>(GD.getDecl());
+ bool HasThisReturn(GlobalDecl GD) const {
+ const CXXMethodDecl *MD = dyn_cast_or_null<CXXMethodDecl>(GD.getDecl());
+ if (!MD) return false;
return ((isa<CXXDestructorDecl>(MD) && GD.getDtorType() != Dtor_Deleting) ||
(isa<CXXConstructorDecl>(MD)));
}
@@ -196,7 +203,7 @@ private:
}
CodeGen::CGCXXABI *CodeGen::CreateItaniumCXXABI(CodeGenModule &CGM) {
- switch (CGM.getContext().getTargetInfo().getCXXABI().getKind()) {
+ switch (CGM.getTarget().getCXXABI().getKind()) {
// For IR-generation purposes, there's no significant difference
// between the ARM and iOS ABIs.
case TargetCXXABI::GenericARM:
@@ -230,8 +237,8 @@ CodeGen::CGCXXABI *CodeGen::CreateItaniumCXXABI(CodeGenModule &CGM) {
llvm::Type *
ItaniumCXXABI::ConvertMemberPointerType(const MemberPointerType *MPT) {
if (MPT->isMemberDataPointer())
- return getPtrDiffTy();
- return llvm::StructType::get(getPtrDiffTy(), getPtrDiffTy(), NULL);
+ return CGM.PtrDiffTy;
+ return llvm::StructType::get(CGM.PtrDiffTy, CGM.PtrDiffTy, NULL);
}
/// In the Itanium and ARM ABIs, method pointers have the form:
@@ -270,8 +277,7 @@ ItaniumCXXABI::EmitLoadOfMemberFunctionPointer(CodeGenFunction &CGF,
CGM.getTypes().GetFunctionType(
CGM.getTypes().arrangeCXXMethodType(RD, FPT));
- llvm::IntegerType *ptrdiff = getPtrDiffTy();
- llvm::Constant *ptrdiff_1 = llvm::ConstantInt::get(ptrdiff, 1);
+ llvm::Constant *ptrdiff_1 = llvm::ConstantInt::get(CGM.PtrDiffTy, 1);
llvm::BasicBlock *FnVirtual = CGF.createBasicBlock("memptr.virtual");
llvm::BasicBlock *FnNonVirtual = CGF.createBasicBlock("memptr.nonvirtual");
@@ -345,7 +351,7 @@ llvm::Value *ItaniumCXXABI::EmitMemberDataPointerAddress(CodeGenFunction &CGF,
llvm::Value *Base,
llvm::Value *MemPtr,
const MemberPointerType *MPT) {
- assert(MemPtr->getType() == getPtrDiffTy());
+ assert(MemPtr->getType() == CGM.PtrDiffTy);
CGBuilderTy &Builder = CGF.Builder;
@@ -493,14 +499,12 @@ ItaniumCXXABI::EmitMemberPointerConversion(const CastExpr *E,
llvm::Constant *
ItaniumCXXABI::EmitNullMemberPointer(const MemberPointerType *MPT) {
- llvm::Type *ptrdiff_t = getPtrDiffTy();
-
// Itanium C++ ABI 2.3:
// A NULL pointer is represented as -1.
if (MPT->isMemberDataPointer())
- return llvm::ConstantInt::get(ptrdiff_t, -1ULL, /*isSigned=*/true);
+ return llvm::ConstantInt::get(CGM.PtrDiffTy, -1ULL, /*isSigned=*/true);
- llvm::Constant *Zero = llvm::ConstantInt::get(ptrdiff_t, 0);
+ llvm::Constant *Zero = llvm::ConstantInt::get(CGM.PtrDiffTy, 0);
llvm::Constant *Values[2] = { Zero, Zero };
return llvm::ConstantStruct::getAnon(Values);
}
@@ -511,7 +515,7 @@ ItaniumCXXABI::EmitMemberDataPointer(const MemberPointerType *MPT,
// Itanium C++ ABI 2.3:
// A pointer to data member is an offset from the base address of
// the class object containing it, represented as a ptrdiff_t
- return llvm::ConstantInt::get(getPtrDiffTy(), offset.getQuantity());
+ return llvm::ConstantInt::get(CGM.PtrDiffTy, offset.getQuantity());
}
llvm::Constant *ItaniumCXXABI::EmitMemberPointer(const CXXMethodDecl *MD) {
@@ -524,7 +528,6 @@ llvm::Constant *ItaniumCXXABI::BuildMemberPointer(const CXXMethodDecl *MD,
MD = MD->getCanonicalDecl();
CodeGenTypes &Types = CGM.getTypes();
- llvm::Type *ptrdiff_t = getPtrDiffTy();
// Get the function pointer (or index if this is a virtual function).
llvm::Constant *MemPtr[2];
@@ -543,16 +546,16 @@ llvm::Constant *ItaniumCXXABI::BuildMemberPointer(const CXXMethodDecl *MD,
// least significant bit of adj then makes exactly the same
// discrimination as the least significant bit of ptr does for
// Itanium.
- MemPtr[0] = llvm::ConstantInt::get(ptrdiff_t, VTableOffset);
- MemPtr[1] = llvm::ConstantInt::get(ptrdiff_t,
+ MemPtr[0] = llvm::ConstantInt::get(CGM.PtrDiffTy, VTableOffset);
+ MemPtr[1] = llvm::ConstantInt::get(CGM.PtrDiffTy,
2 * ThisAdjustment.getQuantity() + 1);
} else {
// Itanium C++ ABI 2.3:
// For a virtual function, [the pointer field] is 1 plus the
// virtual table offset (in bytes) of the function,
// represented as a ptrdiff_t.
- MemPtr[0] = llvm::ConstantInt::get(ptrdiff_t, VTableOffset + 1);
- MemPtr[1] = llvm::ConstantInt::get(ptrdiff_t,
+ MemPtr[0] = llvm::ConstantInt::get(CGM.PtrDiffTy, VTableOffset + 1);
+ MemPtr[1] = llvm::ConstantInt::get(CGM.PtrDiffTy,
ThisAdjustment.getQuantity());
}
} else {
@@ -565,7 +568,7 @@ llvm::Constant *ItaniumCXXABI::BuildMemberPointer(const CXXMethodDecl *MD,
} else {
// Use an arbitrary non-function type to tell GetAddrOfFunction that the
// function type is incomplete.
- Ty = ptrdiff_t;
+ Ty = CGM.PtrDiffTy;
}
llvm::Constant *addr = CGM.GetAddrOfFunction(MD, Ty);
@@ -696,7 +699,7 @@ ItaniumCXXABI::EmitMemberPointerIsNotNull(CodeGenFunction &CGF,
/// For member data pointers, this is just a check against -1.
if (MPT->isMemberDataPointer()) {
- assert(MemPtr->getType() == getPtrDiffTy());
+ assert(MemPtr->getType() == CGM.PtrDiffTy);
llvm::Value *NegativeOne =
llvm::Constant::getAllOnesValue(MemPtr->getType());
return Builder.CreateICmpNE(MemPtr, NegativeOne, "memptr.tobool");
@@ -852,7 +855,7 @@ void ARMCXXABI::EmitInstanceFunctionProlog(CodeGenFunction &CGF) {
CGF.Builder.CreateStore(getThisValue(CGF), CGF.ReturnValue);
}
-void ItaniumCXXABI::EmitConstructorCall(CodeGenFunction &CGF,
+llvm::Value *ItaniumCXXABI::EmitConstructorCall(CodeGenFunction &CGF,
const CXXConstructorDecl *D,
CXXCtorType Type, bool ForVirtualBase,
bool Delegating,
@@ -867,6 +870,7 @@ void ItaniumCXXABI::EmitConstructorCall(CodeGenFunction &CGF,
// FIXME: Provide a source location here.
CGF.EmitCXXMemberCall(D, SourceLocation(), Callee, ReturnValueSlot(), This,
VTT, VTTTy, ArgBeg, ArgEnd);
+ return Callee;
}
RValue ItaniumCXXABI::EmitVirtualDestructorCall(CodeGenFunction &CGF,
@@ -1075,10 +1079,10 @@ void ItaniumCXXABI::EmitGuardedInit(CodeGenFunction &CGF,
bool shouldPerformInit) {
CGBuilderTy &Builder = CGF.Builder;
- // We only need to use thread-safe statics for local variables;
+ // We only need to use thread-safe statics for local non-TLS variables;
// global initialization is always single-threaded.
- bool threadsafe =
- (getContext().getLangOpts().ThreadsafeStatics && D.isLocalVarDecl());
+ bool threadsafe = getContext().getLangOpts().ThreadsafeStatics &&
+ D.isLocalVarDecl() && !D.getTLSKind();
// If we have a global variable with internal linkage and thread-safe statics
// are disabled, we can just let the guard variable be of type i8.
@@ -1113,6 +1117,8 @@ void ItaniumCXXABI::EmitGuardedInit(CodeGenFunction &CGF,
llvm::ConstantInt::get(guardTy, 0),
guardName.str());
guard->setVisibility(var->getVisibility());
+ // If the variable is thread-local, so is its guard variable.
+ guard->setThreadLocalMode(var->getThreadLocalMode());
CGM.setStaticLocalDeclGuardAddress(&D, guard);
}
@@ -1213,7 +1219,14 @@ void ItaniumCXXABI::EmitGuardedInit(CodeGenFunction &CGF,
/// Register a global destructor using __cxa_atexit.
static void emitGlobalDtorWithCXAAtExit(CodeGenFunction &CGF,
llvm::Constant *dtor,
- llvm::Constant *addr) {
+ llvm::Constant *addr,
+ bool TLS) {
+ const char *Name = "__cxa_atexit";
+ if (TLS) {
+ const llvm::Triple &T = CGF.getTarget().getTriple();
+ Name = T.isMacOSX() ? "_tlv_atexit" : "__cxa_thread_atexit";
+ }
+
// We're assuming that the destructor function is something we can
// reasonably call with the default CC. Go ahead and cast it to the
// right prototype.
@@ -1226,8 +1239,7 @@ static void emitGlobalDtorWithCXAAtExit(CodeGenFunction &CGF,
llvm::FunctionType::get(CGF.IntTy, paramTys, false);
// Fetch the actual function.
- llvm::Constant *atexit =
- CGF.CGM.CreateRuntimeFunction(atexitTy, "__cxa_atexit");
+ llvm::Constant *atexit = CGF.CGM.CreateRuntimeFunction(atexitTy, Name);
if (llvm::Function *fn = dyn_cast<llvm::Function>(atexit))
fn->setDoesNotThrow();
@@ -1245,12 +1257,15 @@ static void emitGlobalDtorWithCXAAtExit(CodeGenFunction &CGF,
/// Register a global destructor as best as we know how.
void ItaniumCXXABI::registerGlobalDtor(CodeGenFunction &CGF,
+ const VarDecl &D,
llvm::Constant *dtor,
llvm::Constant *addr) {
// Use __cxa_atexit if available.
- if (CGM.getCodeGenOpts().CXAAtExit) {
- return emitGlobalDtorWithCXAAtExit(CGF, dtor, addr);
- }
+ if (CGM.getCodeGenOpts().CXAAtExit)
+ return emitGlobalDtorWithCXAAtExit(CGF, dtor, addr, D.getTLSKind());
+
+ if (D.getTLSKind())
+ CGM.ErrorUnsupported(&D, "non-trivial TLS destruction");
// In Apple kexts, we want to add a global destructor entry.
// FIXME: shouldn't this be guarded by some variable?
@@ -1261,3 +1276,138 @@ void ItaniumCXXABI::registerGlobalDtor(CodeGenFunction &CGF,
CGF.registerGlobalDtorWithAtExit(dtor, addr);
}
+
+/// Get the appropriate linkage for the wrapper function. This is essentially
+/// the weak form of the variable's linkage; every translation unit which wneeds
+/// the wrapper emits a copy, and we want the linker to merge them.
+static llvm::GlobalValue::LinkageTypes getThreadLocalWrapperLinkage(
+ llvm::GlobalValue::LinkageTypes VarLinkage) {
+ if (llvm::GlobalValue::isLinkerPrivateLinkage(VarLinkage))
+ return llvm::GlobalValue::LinkerPrivateWeakLinkage;
+ // For internal linkage variables, we don't need an external or weak wrapper.
+ if (llvm::GlobalValue::isLocalLinkage(VarLinkage))
+ return VarLinkage;
+ return llvm::GlobalValue::WeakODRLinkage;
+}
+
+llvm::Function *
+ItaniumCXXABI::getOrCreateThreadLocalWrapper(const VarDecl *VD,
+ llvm::GlobalVariable *Var) {
+ // Mangle the name for the thread_local wrapper function.
+ SmallString<256> WrapperName;
+ {
+ llvm::raw_svector_ostream Out(WrapperName);
+ getMangleContext().mangleItaniumThreadLocalWrapper(VD, Out);
+ Out.flush();
+ }
+
+ if (llvm::Value *V = Var->getParent()->getNamedValue(WrapperName))
+ return cast<llvm::Function>(V);
+
+ llvm::Type *RetTy = Var->getType();
+ if (VD->getType()->isReferenceType())
+ RetTy = RetTy->getPointerElementType();
+
+ llvm::FunctionType *FnTy = llvm::FunctionType::get(RetTy, false);
+ llvm::Function *Wrapper = llvm::Function::Create(
+ FnTy, getThreadLocalWrapperLinkage(Var->getLinkage()), WrapperName.str(),
+ &CGM.getModule());
+ // Always resolve references to the wrapper at link time.
+ Wrapper->setVisibility(llvm::GlobalValue::HiddenVisibility);
+ return Wrapper;
+}
+
+void ItaniumCXXABI::EmitThreadLocalInitFuncs(
+ llvm::ArrayRef<std::pair<const VarDecl *, llvm::GlobalVariable *> > Decls,
+ llvm::Function *InitFunc) {
+ for (unsigned I = 0, N = Decls.size(); I != N; ++I) {
+ const VarDecl *VD = Decls[I].first;
+ llvm::GlobalVariable *Var = Decls[I].second;
+
+ // Mangle the name for the thread_local initialization function.
+ SmallString<256> InitFnName;
+ {
+ llvm::raw_svector_ostream Out(InitFnName);
+ getMangleContext().mangleItaniumThreadLocalInit(VD, Out);
+ Out.flush();
+ }
+
+ // If we have a definition for the variable, emit the initialization
+ // function as an alias to the global Init function (if any). Otherwise,
+ // produce a declaration of the initialization function.
+ llvm::GlobalValue *Init = 0;
+ bool InitIsInitFunc = false;
+ if (VD->hasDefinition()) {
+ InitIsInitFunc = true;
+ if (InitFunc)
+ Init =
+ new llvm::GlobalAlias(InitFunc->getType(), Var->getLinkage(),
+ InitFnName.str(), InitFunc, &CGM.getModule());
+ } else {
+ // Emit a weak global function referring to the initialization function.
+ // This function will not exist if the TU defining the thread_local
+ // variable in question does not need any dynamic initialization for
+ // its thread_local variables.
+ llvm::FunctionType *FnTy = llvm::FunctionType::get(CGM.VoidTy, false);
+ Init = llvm::Function::Create(
+ FnTy, llvm::GlobalVariable::ExternalWeakLinkage, InitFnName.str(),
+ &CGM.getModule());
+ }
+
+ if (Init)
+ Init->setVisibility(Var->getVisibility());
+
+ llvm::Function *Wrapper = getOrCreateThreadLocalWrapper(VD, Var);
+ llvm::LLVMContext &Context = CGM.getModule().getContext();
+ llvm::BasicBlock *Entry = llvm::BasicBlock::Create(Context, "", Wrapper);
+ CGBuilderTy Builder(Entry);
+ if (InitIsInitFunc) {
+ if (Init)
+ Builder.CreateCall(Init);
+ } else {
+ // Don't know whether we have an init function. Call it if it exists.
+ llvm::Value *Have = Builder.CreateIsNotNull(Init);
+ llvm::BasicBlock *InitBB = llvm::BasicBlock::Create(Context, "", Wrapper);
+ llvm::BasicBlock *ExitBB = llvm::BasicBlock::Create(Context, "", Wrapper);
+ Builder.CreateCondBr(Have, InitBB, ExitBB);
+
+ Builder.SetInsertPoint(InitBB);
+ Builder.CreateCall(Init);
+ Builder.CreateBr(ExitBB);
+
+ Builder.SetInsertPoint(ExitBB);
+ }
+
+ // For a reference, the result of the wrapper function is a pointer to
+ // the referenced object.
+ llvm::Value *Val = Var;
+ if (VD->getType()->isReferenceType()) {
+ llvm::LoadInst *LI = Builder.CreateLoad(Val);
+ LI->setAlignment(CGM.getContext().getDeclAlign(VD).getQuantity());
+ Val = LI;
+ }
+
+ Builder.CreateRet(Val);
+ }
+}
+
+LValue ItaniumCXXABI::EmitThreadLocalDeclRefExpr(CodeGenFunction &CGF,
+ const DeclRefExpr *DRE) {
+ const VarDecl *VD = cast<VarDecl>(DRE->getDecl());
+ QualType T = VD->getType();
+ llvm::Type *Ty = CGF.getTypes().ConvertTypeForMem(T);
+ llvm::Value *Val = CGF.CGM.GetAddrOfGlobalVar(VD, Ty);
+ llvm::Function *Wrapper =
+ getOrCreateThreadLocalWrapper(VD, cast<llvm::GlobalVariable>(Val));
+
+ Val = CGF.Builder.CreateCall(Wrapper);
+
+ LValue LV;
+ if (VD->getType()->isReferenceType())
+ LV = CGF.MakeNaturalAlignAddrLValue(Val, T);
+ else
+ LV = CGF.MakeAddrLValue(Val, DRE->getType(),
+ CGF.getContext().getDeclAlign(VD));
+ // FIXME: need setObjCGCLValueClass?
+ return LV;
+}