Initial support for struct-path aware TBAA.

Added TBAABaseType and TBAAOffset in LValue. These two fields are initialized to
the actual type and 0, and are updated in EmitLValueForField.
Path-aware TBAA tags are enabled for EmitLoadOfScalar and EmitStoreOfScalar.
Added command line option -struct-path-tbaa.


git-svn-id: https://llvm.org/svn/llvm-project/cfe/trunk@178797 91177308-0d34-0410-b5e6-96231b3b80d8

1 files changed, 15 insertions, 0 deletions

diff --git a/lib/CodeGen/CGValue.h b/lib/CodeGen/CGValue.h
index 0657fdca36..b625b866c0 100644
--- a/lib/CodeGen/CGValue.h
+++ b/lib/CodeGen/CGValue.h
@@ -157,6 +157,11 @@ class LValue {
 
   Expr *BaseIvarExp;
 
+  /// Used by struct-path-aware TBAA.
+  QualType TBAABaseType;
+  /// Offset relative to the base type.
+  uint64_t TBAAOffset;
+
   /// TBAAInfo - TBAA information to attach to dereferences of this LValue.
   llvm::MDNode *TBAAInfo;
 
@@ -175,6 +180,10 @@ private:
     this->ImpreciseLifetime = false;
     this->ThreadLocalRef = false;
     this->BaseIvarExp = 0;
+
+    // Initialize fields for TBAA.
+    this->TBAABaseType = Type;
+    this->TBAAOffset = 0;
     this->TBAAInfo = TBAAInfo;
   }
 
@@ -232,6 +241,12 @@ public:
   Expr *getBaseIvarExp() const { return BaseIvarExp; }
   void setBaseIvarExp(Expr *V) { BaseIvarExp = V; }
 
+  QualType getTBAABaseType() const { return TBAABaseType; }
+  void setTBAABaseType(QualType T) { TBAABaseType = T; }
+
+  uint64_t getTBAAOffset() const { return TBAAOffset; }
+  void setTBAAOffset(uint64_t O) { TBAAOffset = O; }
+
   llvm::MDNode *getTBAAInfo() const { return TBAAInfo; }
   void setTBAAInfo(llvm::MDNode *N) { TBAAInfo = N; }