MIPS: Fix infinite loop in Math.pow(2,-2147483648)

src/mips/code-stubs-mips.cc

Index: src/mips/code-stubs-mips.cc
diff --git a/src/mips/code-stubs-mips.cc b/src/mips/code-stubs-mips.cc
index 47a0a8ea7930394875b406521881cda289432e48..f134cc09f7dab8e7125eb7d463f883c618d042c7 100644
--- a/src/mips/code-stubs-mips.cc
+++ b/src/mips/code-stubs-mips.cc
@@ -823,10 +823,14 @@ void MathPowStub::Generate(MacroAssembler* masm) {
   __ Move(double_result, 1.0);
 
   // Get absolute value of exponent.
-  Label positive_exponent;
+  Label positive_exponent, bail_out;
   __ Branch(&positive_exponent, ge, scratch, Operand(zero_reg));
   __ Subu(scratch, zero_reg, scratch);
+  // Check when Subu overflows and we get negative result
+  // (happens only when input is MIN_INT).
+  __ Branch(&bail_out, gt, zero_reg, Operand(scratch));
   __ bind(&positive_exponent);
+  __ Assert(ge, kUnexpectedNegativeValue, scratch, Operand(zero_reg));
 
   Label while_true, no_carry, loop_end;
   __ bind(&while_true);
@@ -859,6 +863,7 @@ void MathPowStub::Generate(MacroAssembler* masm) {
   __ cvt_d_w(double_exponent, single_scratch);
 
   // Returning or bailing out.
+  __ bind(&bail_out);
   __ push(ra);
   {
     AllowExternalCallThatCantCauseGC scope(masm);