Implement xgetbv and xsetbv.
Patch by Jai Menon.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@126165 91177308-0d34-0410-b5e6-96231b3b80d8
diff --git a/lib/Target/X86/X86MCCodeEmitter.cpp b/lib/Target/X86/X86MCCodeEmitter.cpp
index e6dc74e..0e3b571 100644
--- a/lib/Target/X86/X86MCCodeEmitter.cpp
+++ b/lib/Target/X86/X86MCCodeEmitter.cpp
@@ -979,6 +979,14 @@
     EmitByte(BaseOpcode, CurByte, OS);
     EmitByte(0xF9, CurByte, OS);
     break;
+  case X86II::MRM_D0:
+    EmitByte(BaseOpcode, CurByte, OS);
+    EmitByte(0xD0, CurByte, OS);
+    break;
+  case X86II::MRM_D1:
+    EmitByte(BaseOpcode, CurByte, OS);
+    EmitByte(0xD1, CurByte, OS);
+    break;
   }
 
   // If there is a remaining operand, it must be a trailing immediate.  Emit it