Fix redundant load of bit-fields on assignment (to get the updated

value).
 - Use extra argument to EmitStoreThroughLValue to provide place to
   write update bit-field value if caller requires it.
 - This fixes several FIXMEs.

llvm-svn: 59615

1 files changed, 10 insertions, 1 deletions

diff --git a/clang/lib/CodeGen/CodeGenFunction.h b/clang/lib/CodeGen/CodeGenFunction.h
index 5d99dba69a8..05b2793456b 100644
--- a/clang/lib/CodeGen/CodeGenFunction.h
+++ b/clang/lib/CodeGen/CodeGenFunction.h
@@ -32,6 +32,7 @@ namespace llvm {
   class BasicBlock;
   class Module;
   class SwitchInst;
+  class Value;
 }
 
 namespace clang {
@@ -446,8 +447,16 @@ public:
   void EmitStoreThroughLValue(RValue Src, LValue Dst, QualType Ty);
   void EmitStoreThroughExtVectorComponentLValue(RValue Src, LValue Dst,
                                                 QualType Ty);
-  void EmitStoreThroughBitfieldLValue(RValue Src, LValue Dst, QualType Ty);
   void EmitStoreThroughPropertyRefLValue(RValue Src, LValue Dst, QualType Ty);
+
+  /// EmitStoreThroughLValue - Store Src into Dst with same
+  /// constraints as EmitStoreThroughLValue. 
+  ///
+  /// \param Result [out] - If non-null, this will be set to a Value*
+  /// for the bit-field contents after the store, appropriate for use
+  /// as the result of an assignment to the bit-field.
+  void EmitStoreThroughBitfieldLValue(RValue Src, LValue Dst, QualType Ty,
+                                      llvm::Value **Result=0);
    
   // Note: only availabe for agg return types
   LValue EmitBinaryOperatorLValue(const BinaryOperator *E);