MIPS: Fix FlooringDivByPowerOf2I.

src/mips/lithium-codegen-mips.cc

 // Copyright 2012 the V8 project authors. All rights reserved.7
 // 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 1280 matching lines @@
 }
 
 
 void LCodeGen::DoFlooringDivByPowerOf2I(LFlooringDivByPowerOf2I* instr) {
   Register dividend = ToRegister(instr->dividend());
   Register result = ToRegister(instr->result());
   int32_t divisor = instr->divisor();
   Register scratch = scratch0();
   ASSERT(!scratch.is(dividend));
 
+  // If the divisor is 1, return the dividend.
+  if (divisor == 1) {
+    __ Move(result, dividend);
+    return;
+  }
+
   // If the divisor is positive, things are easy: There can be no deopts and we
   // can simply do an arithmetic right shift.
-  if (divisor == 1) return;
   uint16_t shift = WhichPowerOf2Abs(divisor);
   if (divisor > 1) {
     __ sra(result, dividend, shift);
     return;
   }
 
   // If the divisor is negative, we have to negate and handle edge cases.
   if (instr->hydrogen()->CheckFlag(HValue::kLeftCanBeMinInt)) {
     __ Move(scratch, dividend);
   }
@@ skipping 4600 matching lines @@
   __ lw(result, FieldMemOperand(scratch,
                                 FixedArray::kHeaderSize - kPointerSize));
   __ bind(deferred->exit());
   __ bind(&done);
 }
 
 
 #undef __
 
 } }  // namespace v8::internal