diff --git a/llvm/lib/Target/X86/PeepholeOptimizer.cpp b/llvm/lib/Target/X86/PeepholeOptimizer.cpp
index 42c985d2d637..accbdd6dccb0 100644
--- a/llvm/lib/Target/X86/PeepholeOptimizer.cpp
+++ b/llvm/lib/Target/X86/PeepholeOptimizer.cpp
@@ -94,6 +94,7 @@ bool PH::PeepholeOptimize(MachineBasicBlock &MBB,
     return false;
 
   case X86::ADDri16:  case X86::ADDri32:
+  case X86::ADDmi16:  case X86::ADDmi32:
   case X86::SUBri16:  case X86::SUBri32:
   case X86::ANDri16:  case X86::ANDri32:
   case X86::ORri16:   case X86::ORri32:
@@ -108,6 +109,8 @@ bool PH::PeepholeOptimize(MachineBasicBlock &MBB,
         default: assert(0 && "Unknown opcode value!");
         case X86::ADDri16:  Opcode = X86::ADDri16b; break;
         case X86::ADDri32:  Opcode = X86::ADDri32b; break;
+        case X86::ADDmi16:  Opcode = X86::ADDmi16b; break;
+        case X86::ADDmi32:  Opcode = X86::ADDmi32b; break;
         case X86::SUBri16:  Opcode = X86::SUBri16b; break;
         case X86::SUBri32:  Opcode = X86::SUBri32b; break;
         case X86::ANDri16:  Opcode = X86::ANDri16b; break;