1 files changed, 8 insertions, 0 deletions
diff --git a/llvm/lib/Target/X86/X86InstrInfo.h b/llvm/lib/Target/X86/X86InstrInfo.h
index 839a0f248b6..e0d0342ae6d 100644
--- a/llvm/lib/Target/X86/X86InstrInfo.h
+++ b/llvm/lib/Target/X86/X86InstrInfo.h
@@ -46,6 +46,14 @@ namespace X86 {
     COND_INVALID
   };
   
+  // X86 specific implict values used for subregister inserts. 
+  // This can be used to model the fact that x86-64 by default
+  // inserts 32-bit values into 64-bit registers implicitly containing zeros.
+  enum ImplicitVal {
+    IMPL_VAL_UNDEF = 0,
+    IMPL_VAL_ZERO  = 1
+  };
+  
   // Turn condition code into conditional branch opcode.
   unsigned GetCondBranchFromCond(CondCode CC);