diff --git a/lib/Target/X86/X86ISelLowering.cpp b/lib/Target/X86/X86ISelLowering.cpp
index c5c14f02ae5..f988048a106 100644
--- a/lib/Target/X86/X86ISelLowering.cpp
+++ b/lib/Target/X86/X86ISelLowering.cpp
@@ -7080,6 +7080,14 @@ void X86TargetLowering::LowerAsmOperandForConstraint(SDValue Op,
       }
     }
     return;
+  case 'J':
+    if (ConstantSDNode *C = dyn_cast<ConstantSDNode>(Op)) {
+      if (C->getZExtValue() <= 63) {
+        Result = DAG.getTargetConstant(C->getZExtValue(), Op.getValueType());
+        break;
+      }
+    }
+    return;
   case 'N':
     if (ConstantSDNode *C = dyn_cast<ConstantSDNode>(Op)) {
       if (C->getZExtValue() <= 255) {
diff --git a/test/CodeGen/X86/inline-asm.ll b/test/CodeGen/X86/inline-asm.ll
index 54dfe76478a..02988fcc29f 100644
--- a/test/CodeGen/X86/inline-asm.ll
+++ b/test/CodeGen/X86/inline-asm.ll
@@ -1,21 +1,25 @@
 ; RUN: llvm-as < %s | llc -march=x86
 
-define i32 @test1() {
+define i32 @test1() nounwind {
 	; Dest is AX, dest type = i32.
         %tmp4 = call i32 asm sideeffect "FROB $0", "={ax}"()
         ret i32 %tmp4
 }
 
-define void @test2(i32 %V) {
+define void @test2(i32 %V) nounwind {
 	; input is AX, in type = i32.
         call void asm sideeffect "FROB $0", "{ax}"(i32 %V)
         ret void
 }
 
-define void @test3() {
+define void @test3() nounwind {
         ; FP constant as a memory operand.
         tail call void asm sideeffect "frob $0", "m"( float 0x41E0000000000000)
         ret void
 }
 
-
+define void @test4() nounwind {
+       ; J means a constant in range 0 to 63.
+       tail call void asm sideeffect "bork $0", "J"(i32 37) nounwind
+       ret void
+}