CodeGen: Use 32-bit gep offsets to address vtable address points.

The relative vtable ABI will use a struct rather than an array as the type
of a vtable. LLVM only allows 32-bit integers as struct indices, so we need
to use 32-bit integers to get addresses of address points. In order to keep
the code simple, we might as well do that unconditionally.

It's probably a reasonable implementation limit to support no more than 2
billion virtual functions per class.

This change causes quite a bit of churn in the test suite, so I'm making
it separately.

Differential Revision: http://reviews.llvm.org/D18113

llvm-svn: 263469

1 files changed, 3 insertions, 3 deletions

diff --git a/clang/lib/CodeGen/CGVTT.cpp b/clang/lib/CodeGen/CGVTT.cpp
index 4fb76710d2a..3bf6a7f250c 100644
--- a/clang/lib/CodeGen/CGVTT.cpp
+++ b/clang/lib/CodeGen/CGVTT.cpp
@@ -44,7 +44,7 @@ CodeGenVTables::EmitVTTDefinition(llvm::GlobalVariable *VTT,
                                   const CXXRecordDecl *RD) {
   VTTBuilder Builder(CGM.getContext(), RD, /*GenerateDefinition=*/true);
 
-  llvm::Type *Int8PtrTy = CGM.Int8PtrTy, *Int64Ty = CGM.Int64Ty;
+  llvm::Type *Int8PtrTy = CGM.Int8PtrTy, *Int32Ty = CGM.Int32Ty;
   llvm::ArrayType *ArrayType = 
     llvm::ArrayType::get(Int8PtrTy, Builder.getVTTComponents().size());
 
@@ -75,8 +75,8 @@ CodeGenVTables::EmitVTTDefinition(llvm::GlobalVariable *VTT,
     }
 
      llvm::Value *Idxs[] = {
-       llvm::ConstantInt::get(Int64Ty, 0),
-       llvm::ConstantInt::get(Int64Ty, AddressPoint)
+       llvm::ConstantInt::get(Int32Ty, 0),
+       llvm::ConstantInt::get(Int32Ty, AddressPoint)
      };
 
      llvm::Constant *Init = llvm::ConstantExpr::getInBoundsGetElementPtr(