Struct-path aware TBAA: uniformize scalar tag and path tag.
For struct-path aware TBAA, we used to use scalar type node as the scalar tag,
which has an incompatible format with the struct path tag. We now use the same
format: base type, access type and offset.
We also uniformize the scalar type node and the struct type node: name, a list
of pairs (offset + pointer to MDNode). For scalar type, we have a single pair.
These are to make implementaiton of aliasing rules easier.
git-svn-id: https://llvm.org/svn/llvm-project/cfe/trunk@179335 91177308-0d34-0410-b5e6-96231b3b80d8
diff --git a/lib/CodeGen/CodeGenModule.cpp b/lib/CodeGen/CodeGenModule.cpp
index e8e3d1a..4126bea 100644
--- a/lib/CodeGen/CodeGenModule.cpp
+++ b/lib/CodeGen/CodeGenModule.cpp
@@ -242,9 +242,18 @@
return TBAA->getTBAAStructTagInfo(BaseTy, AccessN, O);
}
+/// Decorate the instruction with a TBAA tag. For scalar TBAA, the tag
+/// is the same as the type. For struct-path aware TBAA, the tag
+/// is different from the type: base type, access type and offset.
+/// When ConvertTypeToTag is true, we create a tag based on the scalar type.
void CodeGenModule::DecorateInstruction(llvm::Instruction *Inst,
- llvm::MDNode *TBAAInfo) {
- Inst->setMetadata(llvm::LLVMContext::MD_tbaa, TBAAInfo);
+ llvm::MDNode *TBAAInfo,
+ bool ConvertTypeToTag) {
+ if (ConvertTypeToTag && TBAA && CodeGenOpts.StructPathTBAA)
+ Inst->setMetadata(llvm::LLVMContext::MD_tbaa,
+ TBAA->getTBAAScalarTagInfo(TBAAInfo));
+ else
+ Inst->setMetadata(llvm::LLVMContext::MD_tbaa, TBAAInfo);
}
bool CodeGenModule::isTargetDarwin() const {