Experimental TBAA support.

This enables metadata generation by default, however the TBAA pass
in the optimizer is still disabled for now.

llvm-svn: 116536

1 files changed, 67 insertions, 0 deletions

diff --git a/clang/lib/CodeGen/CodeGenTBAA.h b/clang/lib/CodeGen/CodeGenTBAA.h
new file mode 100644
index 00000000000..8cfad3b6175
--- /dev/null
+++ b/clang/lib/CodeGen/CodeGenTBAA.h
@@ -0,0 +1,67 @@
+//===--- CodeGenTBAA.h - TBAA information for LLVM CodeGen ------*- C++ -*-===//
+//
+//                     The LLVM Compiler Infrastructure
+//
+// This file is distributed under the University of Illinois Open Source
+// License. See LICENSE.TXT for details.
+//
+//===----------------------------------------------------------------------===//
+//
+// This is the code that manages TBAA information.
+//
+//===----------------------------------------------------------------------===//
+
+#ifndef CLANG_CODEGEN_CODEGENTBAA_H
+#define CLANG_CODEGEN_CODEGENTBAA_H
+
+#include "llvm/LLVMContext.h"
+#include "llvm/ADT/DenseMap.h"
+
+namespace llvm {
+  class LLVMContext;
+  class MDNode;
+}
+
+namespace clang {
+  class ASTContext;
+  class LangOptions;
+  class QualType;
+  class Type;
+
+namespace CodeGen {
+  class CGCXXABI;
+  class CGRecordLayout;
+
+/// CodeGenTBAA - This class organizes the cross-module state that is used
+/// while lowering AST types to LLVM types.
+class CodeGenTBAA {
+  ASTContext &Context;
+  llvm::LLVMContext& VMContext;
+  const LangOptions &Features;
+
+  /// MetadataCache - This maps clang::Types to llvm::MDNodes describing them.
+  llvm::DenseMap<const Type *, llvm::MDNode *> MetadataCache;
+
+  /// Root - This is the mdnode for the root of the metadata type graph
+  /// for this translation unit.
+  llvm::MDNode *Root;
+
+  /// Char - This is the mdnode for "char", which is special, and any types
+  /// considered to be equivalent to it.
+  llvm::MDNode *Char;
+
+  llvm::MDNode *getTBAAInfoForNamedType(const char *NameStr,
+                                        llvm::MDNode *Parent);
+
+public:
+  CodeGenTBAA(ASTContext &Ctx, llvm::LLVMContext &VMContext,
+              const LangOptions &Features);
+  ~CodeGenTBAA();
+
+  llvm::MDNode *getTBAAInfo(QualType QTy);
+};
+
+}  // end namespace CodeGen
+}  // end namespace clang
+
+#endif