Non-allocatable Global Named Register

This patch implements global named registers in Clang, lowering to the just
created intrinsics in LLVM (@llvm.read/write_register). A new type of LValue
had to be created (Register), which just adds support to carry the metadata
node containing the name of the register. Two new methods to emit loads and
stores interoperate with another to emit the named metadata node.

No guarantees are being made and only non-allocatable global variable named
registers are being supported. Local named register support is unchanged.

llvm-svn: 209149

1 files changed, 3 insertions, 0 deletions

diff --git a/clang/lib/CodeGen/CodeGenFunction.h b/clang/lib/CodeGen/CodeGenFunction.h
index 6af7a98d96e..c859ddab773 100644
--- a/clang/lib/CodeGen/CodeGenFunction.h
+++ b/clang/lib/CodeGen/CodeGenFunction.h
@@ -1979,12 +1979,14 @@ public:
   RValue EmitLoadOfLValue(LValue V, SourceLocation Loc);
   RValue EmitLoadOfExtVectorElementLValue(LValue V);
   RValue EmitLoadOfBitfieldLValue(LValue LV);
+  RValue EmitLoadOfGlobalRegLValue(LValue LV);
 
   /// EmitStoreThroughLValue - Store the specified rvalue into the specified
   /// lvalue, where both are guaranteed to the have the same type, and that type
   /// is 'Ty'.
   void EmitStoreThroughLValue(RValue Src, LValue Dst, bool isInit=false);
   void EmitStoreThroughExtVectorComponentLValue(RValue Src, LValue Dst);
+  void EmitStoreThroughGlobalRegLValue(RValue Src, LValue Dst);
 
   /// EmitStoreThroughBitfieldLValue - Store Src into Dst with same constraints
   /// as EmitStoreThroughLValue.
@@ -2009,6 +2011,7 @@ public:
   // Note: only available for agg return types
   LValue EmitVAArgExprLValue(const VAArgExpr *E);
   LValue EmitDeclRefLValue(const DeclRefExpr *E);
+  LValue EmitReadRegister(const VarDecl *VD);
   LValue EmitStringLiteralLValue(const StringLiteral *E);
   LValue EmitObjCEncodeExprLValue(const ObjCEncodeExpr *E);
   LValue EmitPredefinedLValue(const PredefinedExpr *E);