Amusingly, I missed this point of abstraction in all my earlier
member-pointer refactoring: dereferencing a member data pointer.
git-svn-id: https://llvm.org/svn/llvm-project/cfe/trunk@112640 91177308-0d34-0410-b5e6-96231b3b80d8
diff --git a/lib/CodeGen/CGCXX.cpp b/lib/CodeGen/CGCXX.cpp
index fbea420..f8d81fa 100644
--- a/lib/CodeGen/CGCXX.cpp
+++ b/lib/CodeGen/CGCXX.cpp
@@ -359,6 +359,15 @@
return llvm::Constant::getNullValue(FTy->getPointerTo());
}
+llvm::Value *CGCXXABI::EmitMemberDataPointerAddress(CodeGenFunction &CGF,
+ llvm::Value *Base,
+ llvm::Value *MemPtr,
+ const MemberPointerType *MPT) {
+ ErrorUnsupportedABI(CGF, "loads of member pointers");
+ const llvm::Type *Ty = CGF.ConvertType(MPT->getPointeeType())->getPointerTo();
+ return llvm::Constant::getNullValue(Ty);
+}
+
llvm::Value *CGCXXABI::EmitMemberPointerConversion(CodeGenFunction &CGF,
const CastExpr *E,
llvm::Value *Src) {
diff --git a/lib/CodeGen/CGCXXABI.h b/lib/CodeGen/CGCXXABI.h
index b87d6c0..8d3e70f 100644
--- a/lib/CodeGen/CGCXXABI.h
+++ b/lib/CodeGen/CGCXXABI.h
@@ -88,6 +88,12 @@
llvm::Value *MemPtr,
const MemberPointerType *MPT);
+ /// Calculate an l-value from an object and a data member pointer.
+ virtual llvm::Value *EmitMemberDataPointerAddress(CodeGenFunction &CGF,
+ llvm::Value *Base,
+ llvm::Value *MemPtr,
+ const MemberPointerType *MPT);
+
/// Perform a derived-to-base or base-to-derived member pointer
/// conversion.
virtual llvm::Value *EmitMemberPointerConversion(CodeGenFunction &CGF,
diff --git a/lib/CodeGen/CGExpr.cpp b/lib/CodeGen/CGExpr.cpp
index a676333..1af0d56 100644
--- a/lib/CodeGen/CGExpr.cpp
+++ b/lib/CodeGen/CGExpr.cpp
@@ -2090,16 +2090,15 @@
BaseV = EmitScalarExpr(E->getLHS());
else
BaseV = EmitLValue(E->getLHS()).getAddress();
- const llvm::Type *i8Ty = llvm::Type::getInt8PtrTy(getLLVMContext());
- BaseV = Builder.CreateBitCast(BaseV, i8Ty);
- llvm::Value *OffsetV = EmitScalarExpr(E->getRHS());
- llvm::Value *AddV = Builder.CreateInBoundsGEP(BaseV, OffsetV, "add.ptr");
- QualType Ty = E->getRHS()->getType();
- Ty = Ty->getAs<MemberPointerType>()->getPointeeType();
-
- const llvm::Type *PType = ConvertType(getContext().getPointerType(Ty));
- AddV = Builder.CreateBitCast(AddV, PType);
- return MakeAddrLValue(AddV, Ty);
+ llvm::Value *OffsetV = EmitScalarExpr(E->getRHS());
+
+ const MemberPointerType *MPT
+ = E->getRHS()->getType()->getAs<MemberPointerType>();
+
+ llvm::Value *AddV =
+ CGM.getCXXABI().EmitMemberDataPointerAddress(*this, BaseV, OffsetV, MPT);
+
+ return MakeAddrLValue(AddV, MPT->getPointeeType());
}
diff --git a/lib/CodeGen/ItaniumCXXABI.cpp b/lib/CodeGen/ItaniumCXXABI.cpp
index 920b833..1376800 100644
--- a/lib/CodeGen/ItaniumCXXABI.cpp
+++ b/lib/CodeGen/ItaniumCXXABI.cpp
@@ -66,6 +66,11 @@
llvm::Value *MemFnPtr,
const MemberPointerType *MPT);
+ llvm::Value *EmitMemberDataPointerAddress(CodeGenFunction &CGF,
+ llvm::Value *Base,
+ llvm::Value *MemPtr,
+ const MemberPointerType *MPT);
+
llvm::Value *EmitMemberPointerConversion(CodeGenFunction &CGF,
const CastExpr *E,
llvm::Value *Src);
@@ -261,6 +266,31 @@
return Callee;
}
+/// Compute an l-value by applying the given pointer-to-member to a
+/// base object.
+llvm::Value *ItaniumCXXABI::EmitMemberDataPointerAddress(CodeGenFunction &CGF,
+ llvm::Value *Base,
+ llvm::Value *MemPtr,
+ const MemberPointerType *MPT) {
+ assert(MemPtr->getType() == getPtrDiffTy());
+
+ CGBuilderTy &Builder = CGF.Builder;
+
+ unsigned AS = cast<llvm::PointerType>(Base->getType())->getAddressSpace();
+
+ // Cast to char*.
+ Base = Builder.CreateBitCast(Base, Builder.getInt8Ty()->getPointerTo(AS));
+
+ // Apply the offset, which we assume is non-null.
+ llvm::Value *Addr = Builder.CreateInBoundsGEP(Base, MemPtr, "memptr.offset");
+
+ // Cast the address to the appropriate pointer type, adopting the
+ // address space of the base pointer.
+ const llvm::Type *PType
+ = CGF.ConvertType(MPT->getPointeeType())->getPointerTo(AS);
+ return Builder.CreateBitCast(Addr, PType);
+}
+
/// Perform a derived-to-base or base-to-derived member pointer conversion.
///
/// Obligatory offset/adjustment diagram: