Fix Double.pow() for arm and mips

runtime/vm/intermediate_language_mips.cc

Index: runtime/vm/intermediate_language_mips.cc
diff --git a/runtime/vm/intermediate_language_mips.cc b/runtime/vm/intermediate_language_mips.cc
index d61337d52f38a965917fbdb336448c81a91d5052..793c1b43d93f959a7a8032aba7ec00fd1deb4eed 100644
--- a/runtime/vm/intermediate_language_mips.cc
+++ b/runtime/vm/intermediate_language_mips.cc
@@ -4580,15 +4580,15 @@ static void InvokeDoublePow(FlowGraphCompiler* compiler,
 
   __ Bind(&try_sqrt);
   // Before calling pow, check if we could use sqrt instead of pow.
-  __ LoadImmediate(result, kPosInfinity);
-  // base == Infinity -> call pow;
+  __ LoadImmediate(result, kNegInfinity);
+  // base == -Infinity -> call pow;
   __ ceqd(base, result);
   Label do_pow;
   __ bc1t(&do_pow);
 
   // exponent == 0.5 ?
   __ LoadImmediate(result, 0.5);
-  __ ceqd(base, result);
+  __ ceqd(exp, result);
   __ bc1f(&do_pow);
 
   // base == 0 -> return 0;