[cfe-commits] r99365 - in /cfe/trunk/lib/CodeGen: CGVtable.cpp CodeGenFunction.h
Anders Carlsson
andersca at mac.com
Tue Mar 23 17:39:19 PDT 2010
Author: andersca
Date: Tue Mar 23 19:39:18 2010
New Revision: 99365
URL: http://llvm.org/viewvc/llvm-project?rev=99365&view=rev
Log:
Add CodeGenFunction::GenerateThunk and implement it.
Modified:
cfe/trunk/lib/CodeGen/CGVtable.cpp
cfe/trunk/lib/CodeGen/CodeGenFunction.h
Modified: cfe/trunk/lib/CodeGen/CGVtable.cpp
URL: http://llvm.org/viewvc/llvm-project/cfe/trunk/lib/CodeGen/CGVtable.cpp?rev=99365&r1=99364&r2=99365&view=diff
==============================================================================
--- cfe/trunk/lib/CodeGen/CGVtable.cpp (original)
+++ cfe/trunk/lib/CodeGen/CGVtable.cpp Tue Mar 23 19:39:18 2010
@@ -3666,6 +3666,178 @@
return GetOrCreateLLVMFunction(Name, Ty, GlobalDecl());
}
+static llvm::Value *PerformTypeAdjustment(CodeGenFunction &CGF,
+ llvm::Value *Ptr,
+ int64_t NonVirtualAdjustment,
+ int64_t VirtualAdjustment) {
+ if (!NonVirtualAdjustment && !VirtualAdjustment)
+ return Ptr;
+
+ const llvm::Type *Int8PtrTy =
+ llvm::Type::getInt8PtrTy(CGF.getLLVMContext());
+
+ llvm::Value *V = CGF.Builder.CreateBitCast(Ptr, Int8PtrTy);
+
+ if (NonVirtualAdjustment) {
+ // Do the non-virtual adjustment.
+ V = CGF.Builder.CreateConstInBoundsGEP1_64(V, NonVirtualAdjustment);
+ }
+
+ if (VirtualAdjustment) {
+ const llvm::Type *PtrDiffTy =
+ CGF.ConvertType(CGF.getContext().getPointerDiffType());
+
+ // Do the virtual adjustment.
+ llvm::Value *VTablePtrPtr =
+ CGF.Builder.CreateBitCast(V, Int8PtrTy->getPointerTo());
+
+ llvm::Value *VTablePtr = CGF.Builder.CreateLoad(VTablePtrPtr);
+
+ llvm::Value *OffsetPtr =
+ CGF.Builder.CreateConstInBoundsGEP1_64(VTablePtr, VirtualAdjustment);
+
+ OffsetPtr = CGF.Builder.CreateBitCast(OffsetPtr, PtrDiffTy->getPointerTo());
+
+ // Load the adjustment offset from the vtable.
+ llvm::Value *Offset = CGF.Builder.CreateLoad(OffsetPtr);
+
+ // Adjust our pointer.
+ V = CGF.Builder.CreateInBoundsGEP(V, Offset);
+ }
+
+ // Cast back to the original type.
+ return CGF.Builder.CreateBitCast(V, Ptr->getType());
+}
+
+void CodeGenFunction::GenerateThunk(llvm::Function *Fn, GlobalDecl GD,
+ const ThunkInfo &Thunk) {
+ const CXXMethodDecl *MD = cast<CXXMethodDecl>(GD.getDecl());
+ const FunctionProtoType *FPT = MD->getType()->getAs<FunctionProtoType>();
+ QualType ResultType = FPT->getResultType();
+ QualType ThisType = MD->getThisType(getContext());
+
+ FunctionArgList FunctionArgs;
+
+ // FIXME: It would be nice if more of this code could be shared with
+ // CodeGenFunction::GenerateCode.
+
+ // Create the implicit 'this' parameter declaration.
+ CXXThisDecl = ImplicitParamDecl::Create(getContext(), 0,
+ MD->getLocation(),
+ &getContext().Idents.get("this"),
+ ThisType);
+
+ // Add the 'this' parameter.
+ FunctionArgs.push_back(std::make_pair(CXXThisDecl, CXXThisDecl->getType()));
+
+ // Add the rest of the parameters.
+ for (FunctionDecl::param_const_iterator I = MD->param_begin(),
+ E = MD->param_end(); I != E; ++I) {
+ ParmVarDecl *Param = *I;
+
+ FunctionArgs.push_back(std::make_pair(Param, Param->getType()));
+ }
+
+ StartFunction(GlobalDecl(), ResultType, Fn, FunctionArgs, SourceLocation());
+
+ // Adjust the 'this' pointer if necessary.
+ llvm::Value *AdjustedThisPtr =
+ PerformTypeAdjustment(*this, LoadCXXThis(),
+ Thunk.This.NonVirtual,
+ Thunk.This.VCallOffsetOffset);
+
+ CallArgList CallArgs;
+
+ // Add our adjusted 'this' pointer.
+ CallArgs.push_back(std::make_pair(RValue::get(AdjustedThisPtr), ThisType));
+
+ // Add the rest of the parameters.
+ for (FunctionDecl::param_const_iterator I = MD->param_begin(),
+ E = MD->param_end(); I != E; ++I) {
+ ParmVarDecl *Param = *I;
+ QualType ArgType = Param->getType();
+
+ // FIXME: Declaring a DeclRefExpr on the stack is kinda icky.
+ DeclRefExpr ArgExpr(Param, ArgType.getNonReferenceType(), SourceLocation());
+ CallArgs.push_back(std::make_pair(EmitCallArg(&ArgExpr, ArgType), ArgType));
+ }
+
+ // Get our callee.
+ const llvm::Type *Ty =
+ CGM.getTypes().GetFunctionType(CGM.getTypes().getFunctionInfo(MD),
+ FPT->isVariadic());
+ llvm::Value *Callee = CGM.GetAddrOfFunction(GD, Ty);
+
+ const CGFunctionInfo &FnInfo =
+ CGM.getTypes().getFunctionInfo(ResultType, CallArgs, FPT->getCallConv(),
+ FPT->getNoReturnAttr());
+
+ // Now emit our call.
+ RValue RV = EmitCall(FnInfo, Callee, ReturnValueSlot(), CallArgs, MD);
+
+ if (!Thunk.Return.isEmpty()) {
+ // Emit the return adjustment.
+ bool NullCheckValue = !ResultType->isReferenceType();
+
+ llvm::BasicBlock *AdjustNull = 0;
+ llvm::BasicBlock *AdjustNotNull = 0;
+ llvm::BasicBlock *AdjustEnd = 0;
+
+ llvm::Value *ReturnValue = RV.getScalarVal();
+
+ if (NullCheckValue) {
+ AdjustNull = createBasicBlock("adjust.null");
+ AdjustNotNull = createBasicBlock("adjust.notnull");
+ AdjustEnd = createBasicBlock("adjust.end");
+
+ llvm::Value *IsNull = Builder.CreateIsNull(ReturnValue);
+ Builder.CreateCondBr(IsNull, AdjustNull, AdjustNotNull);
+ EmitBlock(AdjustNotNull);
+ }
+
+ ReturnValue = PerformTypeAdjustment(*this, ReturnValue,
+ Thunk.Return.NonVirtual,
+ Thunk.Return.VBaseOffsetOffset);
+
+ if (NullCheckValue) {
+ Builder.CreateBr(AdjustEnd);
+ EmitBlock(AdjustNull);
+ Builder.CreateBr(AdjustEnd);
+ EmitBlock(AdjustEnd);
+
+ llvm::PHINode *PHI = Builder.CreatePHI(ReturnValue->getType());
+ PHI->reserveOperandSpace(2);
+ PHI->addIncoming(ReturnValue, AdjustNotNull);
+ PHI->addIncoming(llvm::Constant::getNullValue(ReturnValue->getType()),
+ AdjustNull);
+ ReturnValue = PHI;
+ }
+
+ RV = RValue::get(ReturnValue);
+ }
+
+ if (!ResultType->isVoidType())
+ EmitReturnOfRValue(RV, ResultType);
+
+ FinishFunction();
+
+ // Destroy the 'this' declaration.
+ CXXThisDecl->Destroy(getContext());
+
+ // Set the right linkage.
+ llvm::GlobalValue::LinkageTypes ThunkLinkage;
+
+ if (CGM.getFunctionLinkage(MD) == llvm::Function::InternalLinkage)
+ ThunkLinkage = llvm::Function::InternalLinkage;
+ else
+ ThunkLinkage = llvm::Function::WeakAnyLinkage;
+
+ Fn->setLinkage(ThunkLinkage);
+
+ // Set the right visibility.
+ CGM.setGlobalVisibility(Fn, MD);
+}
+
void CodeGenVTables::EmitThunk(GlobalDecl GD, const ThunkInfo &Thunk)
{
llvm::Constant *Entry = CGM.GetAddrOfThunk(GD, Thunk);
@@ -3701,6 +3873,10 @@
// Remove the old thunk.
OldThunkFn->eraseFromParent();
}
+
+ // Actually generate the thunk body.
+ llvm::Function *ThunkFn = cast<llvm::Function>(Entry);
+ CodeGenFunction(CGM).GenerateThunk(ThunkFn, GD, Thunk);
}
void CodeGenVTables::EmitThunks(GlobalDecl GD)
Modified: cfe/trunk/lib/CodeGen/CodeGenFunction.h
URL: http://llvm.org/viewvc/llvm-project/cfe/trunk/lib/CodeGen/CodeGenFunction.h?rev=99365&r1=99364&r2=99365&view=diff
==============================================================================
--- cfe/trunk/lib/CodeGen/CodeGenFunction.h (original)
+++ cfe/trunk/lib/CodeGen/CodeGenFunction.h Tue Mar 23 19:39:18 2010
@@ -510,7 +510,9 @@
llvm::Value *DynamicTypeAdjust(llvm::Value *V,
const ThunkAdjustment &Adjustment);
- /// GenerateThunk - Generate a thunk for the given method
+ /// GenerateThunk - Generate a thunk for the given method.
+ void GenerateThunk(llvm::Function *Fn, GlobalDecl GD, const ThunkInfo &Thunk);
+
llvm::Constant *GenerateThunk(llvm::Function *Fn, GlobalDecl GD,
bool Extern,
const ThunkAdjustment &ThisAdjustment);
More information about the cfe-commits
mailing list