MIPS: Fix debug mode webkit failures.

src/mips/lithium-codegen-mips.cc

 // Copyright 2012 the V8 project authors. All rights reserved.
 // Redistribution and use in source and binary forms, with or without
 // modification, are permitted provided that the following conditions are
 // met:
 //
 //     * Redistributions of source code must retain the above copyright
 //       notice, this list of conditions and the following disclaimer.
 //     * Redistributions in binary form must reproduce the above
 //       copyright notice, this list of conditions and the following
 //       disclaimer in the documentation and/or other materials provided
@@ skipping 389 matching lines @@
   if (op->IsRegister()) {
     return ToRegister(op->index());
   } else if (op->IsConstantOperand()) {
     LConstantOperand* const_op = LConstantOperand::cast(op);
     HConstant* constant = chunk_->LookupConstant(const_op);
     Handle<Object> literal = constant->handle();
     Representation r = chunk_->LookupLiteralRepresentation(const_op);
     if (r.IsInteger32()) {
       ASSERT(literal->IsNumber());
       __ li(scratch, Operand(static_cast<int32_t>(literal->Number())));
+    } else if (r.IsSmi()) {
+      ASSERT(constant->HasSmiValue());
+      __ li(scratch, Operand(Smi::FromInt(constant->Integer32Value())));
     } else if (r.IsDouble()) {
       Abort("EmitLoadRegister: Unsupported double immediate.");
     } else {
       ASSERT(r.IsTagged());
       __ LoadObject(scratch, literal);
     }
     return scratch;
   } else if (op->IsStackSlot() || op->IsArgument()) {
     __ lw(scratch, ToMemOperand(op));
     return scratch;
@@ skipping 5427 matching lines @@
   __ Subu(scratch, result, scratch);
   __ lw(result, FieldMemOperand(scratch,
                                 FixedArray::kHeaderSize - kPointerSize));
   __ bind(&done);
 }
 
 
 #undef __
 
 } }  // namespace v8::internal