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/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: