Add basic support for adding !tbaa.struct metadata on llvm.memcpy calls for

struct assignment.


git-svn-id: https://llvm.org/svn/llvm-project/cfe/trunk@164853 91177308-0d34-0410-b5e6-96231b3b80d8

1 files changed, 15 insertions, 0 deletions

diff --git a/lib/CodeGen/CodeGenTBAA.h b/lib/CodeGen/CodeGenTBAA.h
index c17a5cf03c..eedb996f3e 100644
--- a/lib/CodeGen/CodeGenTBAA.h
+++ b/lib/CodeGen/CodeGenTBAA.h
@@ -49,6 +49,10 @@ class CodeGenTBAA {
   /// MetadataCache - This maps clang::Types to llvm::MDNodes describing them.
   llvm::DenseMap<const Type *, llvm::MDNode *> MetadataCache;
 
+  /// StructMetadataCache - This maps clang::Types to llvm::MDNodes describing
+  /// them for struct assignments.
+  llvm::DenseMap<const Type *, llvm::MDNode *> StructMetadataCache;
+
   llvm::MDNode *Root;
   llvm::MDNode *Char;
 
@@ -60,6 +64,13 @@ class CodeGenTBAA {
   /// considered to be equivalent to it.
   llvm::MDNode *getChar();
 
+  /// CollectFields - Collect information about the fields of a type for
+  /// !tbaa.struct metadata formation. Return false for an unsupported type.
+  bool CollectFields(uint64_t BaseOffset,
+                     QualType Ty,
+                     SmallVectorImpl<llvm::MDBuilder::TBAAStructField> &Fields,
+                     bool MayAlias);
+
 public:
   CodeGenTBAA(ASTContext &Ctx, llvm::LLVMContext &VMContext,
               const CodeGenOptions &CGO,
@@ -74,6 +85,10 @@ public:
   /// getTBAAInfoForVTablePtr - Get the TBAA MDNode to be used for a
   /// dereference of a vtable pointer.
   llvm::MDNode *getTBAAInfoForVTablePtr();
+
+  /// getTBAAStructInfo - Get the TBAAStruct MDNode to be used for a memcpy of
+  /// the given type.
+  llvm::MDNode *getTBAAStructInfo(QualType QTy);
 };
 
 }  // end namespace CodeGen