MIPS: [turbofan] Optimize fpu compares with zero literal.

src/mips/macro-assembler-mips.h

Index: src/mips/macro-assembler-mips.h
diff --git a/src/mips/macro-assembler-mips.h b/src/mips/macro-assembler-mips.h
index 85ba81d82cbdaf54c1ee58c2d95ca2594d574d7c..34565ed626c83b387bcebe249c2611dc2d7b3739 100644
--- a/src/mips/macro-assembler-mips.h
+++ b/src/mips/macro-assembler-mips.h
@@ -1625,6 +1625,8 @@ const Operand& rt = Operand(zero_reg), BranchDelaySlot bd = PROTECT
   void JumpIfDictionaryInPrototypeChain(Register object, Register scratch0,
                                         Register scratch1, Label* found);
 
+  bool IsDoubleZeroRegSet() { return has_double_zero_reg_set_; }
+
  private:
   void CallCFunctionHelper(Register function,
                            int num_reg_arguments,