Restore r184205 and associated commits (after commit of r185290)
This allows clang to use the backend parameter attribute 'returned' when generating 'this'-returning constructors and destructors in ARM and MSVC C++ ABIs.
git-svn-id: https://llvm.org/svn/llvm-project/cfe/trunk@185291 91177308-0d34-0410-b5e6-96231b3b80d8
diff --git a/lib/CodeGen/ItaniumCXXABI.cpp b/lib/CodeGen/ItaniumCXXABI.cpp
index 67174c0..279c212 100644
--- a/lib/CodeGen/ItaniumCXXABI.cpp
+++ b/lib/CodeGen/ItaniumCXXABI.cpp
@@ -119,20 +119,17 @@
void EmitInstanceFunctionProlog(CodeGenFunction &CGF);
- llvm::Value *EmitConstructorCall(CodeGenFunction &CGF,
- const CXXConstructorDecl *D,
- CXXCtorType Type, bool ForVirtualBase,
- bool Delegating,
+ void EmitConstructorCall(CodeGenFunction &CGF,
+ const CXXConstructorDecl *D, CXXCtorType Type,
+ bool ForVirtualBase, bool Delegating,
llvm::Value *This,
CallExpr::const_arg_iterator ArgBeg,
CallExpr::const_arg_iterator ArgEnd);
- RValue EmitVirtualDestructorCall(CodeGenFunction &CGF,
- const CXXDestructorDecl *Dtor,
- CXXDtorType DtorType,
- SourceLocation CallLoc,
- ReturnValueSlot ReturnValue,
- llvm::Value *This);
+ void EmitVirtualDestructorCall(CodeGenFunction &CGF,
+ const CXXDestructorDecl *Dtor,
+ CXXDtorType DtorType, SourceLocation CallLoc,
+ llvm::Value *This);
void EmitVirtualInheritanceTables(llvm::GlobalVariable::LinkageTypes Linkage,
const CXXRecordDecl *RD);
@@ -170,21 +167,11 @@
public:
ARMCXXABI(CodeGen::CodeGenModule &CGM) : ItaniumCXXABI(CGM, /*ARM*/ true) {}
- void BuildConstructorSignature(const CXXConstructorDecl *Ctor,
- CXXCtorType T,
- CanQualType &ResTy,
- SmallVectorImpl<CanQualType> &ArgTys);
-
- void BuildDestructorSignature(const CXXDestructorDecl *Dtor,
- CXXDtorType T,
- CanQualType &ResTy,
- SmallVectorImpl<CanQualType> &ArgTys);
-
- void BuildInstanceFunctionParams(CodeGenFunction &CGF,
- QualType &ResTy,
- FunctionArgList &Params);
-
- void EmitInstanceFunctionProlog(CodeGenFunction &CGF);
+ bool HasThisReturn(GlobalDecl GD) const {
+ return (isa<CXXConstructorDecl>(GD.getDecl()) || (
+ isa<CXXDestructorDecl>(GD.getDecl()) &&
+ GD.getDtorType() != Dtor_Deleting));
+ }
void EmitReturnFromThunk(CodeGenFunction &CGF, RValue RV, QualType ResTy);
@@ -196,15 +183,6 @@
QualType ElementType);
llvm::Value *readArrayCookieImpl(CodeGenFunction &CGF, llvm::Value *allocPtr,
CharUnits cookieSize);
-
- /// \brief Returns true if the given instance method is one of the
- /// kinds that the ARM ABI says returns 'this'.
- 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)));
- }
};
}
@@ -759,22 +737,14 @@
SmallVectorImpl<CanQualType> &ArgTys) {
ASTContext &Context = getContext();
- // 'this' is already there.
+ // 'this' parameter is already there, as well as 'this' return if
+ // HasThisReturn(GlobalDecl(Ctor, Type)) is true
// Check if we need to add a VTT parameter (which has type void **).
if (Type == Ctor_Base && Ctor->getParent()->getNumVBases() != 0)
ArgTys.push_back(Context.getPointerType(Context.VoidPtrTy));
}
-/// The ARM ABI does the same as the Itanium ABI, but returns 'this'.
-void ARMCXXABI::BuildConstructorSignature(const CXXConstructorDecl *Ctor,
- CXXCtorType Type,
- CanQualType &ResTy,
- SmallVectorImpl<CanQualType> &ArgTys) {
- ItaniumCXXABI::BuildConstructorSignature(Ctor, Type, ResTy, ArgTys);
- ResTy = ArgTys[0];
-}
-
/// The generic ABI passes 'this', plus a VTT if it's destroying a
/// base subobject.
void ItaniumCXXABI::BuildDestructorSignature(const CXXDestructorDecl *Dtor,
@@ -783,25 +753,14 @@
SmallVectorImpl<CanQualType> &ArgTys) {
ASTContext &Context = getContext();
- // 'this' is already there.
+ // 'this' parameter is already there, as well as 'this' return if
+ // HasThisReturn(GlobalDecl(Dtor, Type)) is true
// Check if we need to add a VTT parameter (which has type void **).
if (Type == Dtor_Base && Dtor->getParent()->getNumVBases() != 0)
ArgTys.push_back(Context.getPointerType(Context.VoidPtrTy));
}
-/// The ARM ABI does the same as the Itanium ABI, but returns 'this'
-/// for non-deleting destructors.
-void ARMCXXABI::BuildDestructorSignature(const CXXDestructorDecl *Dtor,
- CXXDtorType Type,
- CanQualType &ResTy,
- SmallVectorImpl<CanQualType> &ArgTys) {
- ItaniumCXXABI::BuildDestructorSignature(Dtor, Type, ResTy, ArgTys);
-
- if (Type != Dtor_Deleting)
- ResTy = ArgTys[0];
-}
-
void ItaniumCXXABI::BuildInstanceFunctionParams(CodeGenFunction &CGF,
QualType &ResTy,
FunctionArgList &Params) {
@@ -825,16 +784,6 @@
}
}
-void ARMCXXABI::BuildInstanceFunctionParams(CodeGenFunction &CGF,
- QualType &ResTy,
- FunctionArgList &Params) {
- ItaniumCXXABI::BuildInstanceFunctionParams(CGF, ResTy, Params);
-
- // Return 'this' from certain constructors and destructors.
- if (HasThisReturn(CGF.CurGD))
- ResTy = Params[0]->getType();
-}
-
void ItaniumCXXABI::EmitInstanceFunctionProlog(CodeGenFunction &CGF) {
/// Initialize the 'this' slot.
EmitThisParam(CGF);
@@ -845,21 +794,23 @@
= CGF.Builder.CreateLoad(CGF.GetAddrOfLocalVar(getVTTDecl(CGF)),
"vtt");
}
-}
-void ARMCXXABI::EmitInstanceFunctionProlog(CodeGenFunction &CGF) {
- ItaniumCXXABI::EmitInstanceFunctionProlog(CGF);
-
- /// Initialize the return slot to 'this' at the start of the
- /// function.
+ /// If this is a function that the ABI specifies returns 'this', initialize
+ /// the return slot to 'this' at the start of the function.
+ ///
+ /// Unlike the setting of return types, this is done within the ABI
+ /// implementation instead of by clients of CGCXXABI because:
+ /// 1) getThisValue is currently protected
+ /// 2) in theory, an ABI could implement 'this' returns some other way;
+ /// HasThisReturn only specifies a contract, not the implementation
if (HasThisReturn(CGF.CurGD))
CGF.Builder.CreateStore(getThisValue(CGF), CGF.ReturnValue);
}
-llvm::Value *ItaniumCXXABI::EmitConstructorCall(CodeGenFunction &CGF,
+void ItaniumCXXABI::EmitConstructorCall(CodeGenFunction &CGF,
const CXXConstructorDecl *D,
- CXXCtorType Type, bool ForVirtualBase,
- bool Delegating,
+ CXXCtorType Type,
+ bool ForVirtualBase, bool Delegating,
llvm::Value *This,
CallExpr::const_arg_iterator ArgBeg,
CallExpr::const_arg_iterator ArgEnd) {
@@ -869,17 +820,15 @@
llvm::Value *Callee = CGM.GetAddrOfCXXConstructor(D, Type);
// FIXME: Provide a source location here.
- CGF.EmitCXXMemberCall(D, SourceLocation(), Callee, ReturnValueSlot(), This,
- VTT, VTTTy, ArgBeg, ArgEnd);
- return Callee;
+ CGF.EmitCXXMemberCall(D, SourceLocation(), Callee, ReturnValueSlot(),
+ This, VTT, VTTTy, ArgBeg, ArgEnd);
}
-RValue ItaniumCXXABI::EmitVirtualDestructorCall(CodeGenFunction &CGF,
- const CXXDestructorDecl *Dtor,
- CXXDtorType DtorType,
- SourceLocation CallLoc,
- ReturnValueSlot ReturnValue,
- llvm::Value *This) {
+void ItaniumCXXABI::EmitVirtualDestructorCall(CodeGenFunction &CGF,
+ const CXXDestructorDecl *Dtor,
+ CXXDtorType DtorType,
+ SourceLocation CallLoc,
+ llvm::Value *This) {
assert(DtorType == Dtor_Deleting || DtorType == Dtor_Complete);
const CGFunctionInfo *FInfo
@@ -887,8 +836,8 @@
llvm::Type *Ty = CGF.CGM.getTypes().GetFunctionType(*FInfo);
llvm::Value *Callee = CGF.BuildVirtualCall(Dtor, DtorType, This, Ty);
- return CGF.EmitCXXMemberCall(Dtor, CallLoc, Callee, ReturnValue, This,
- /*ImplicitParam=*/0, QualType(), 0, 0);
+ CGF.EmitCXXMemberCall(Dtor, CallLoc, Callee, ReturnValueSlot(), This,
+ /*ImplicitParam=*/0, QualType(), 0, 0);
}
void ItaniumCXXABI::EmitVirtualInheritanceTables(