Fixed constant folding for Math.clz32.

src/hydrogen-instructions.cc

Index: src/hydrogen-instructions.cc
diff --git a/src/hydrogen-instructions.cc b/src/hydrogen-instructions.cc
index 29d4e73cba431761f19b5f751e76f2007e51e2e9..a35134952da753ee932fd104ee680e06f5173d2f 100644
--- a/src/hydrogen-instructions.cc
+++ b/src/hydrogen-instructions.cc
@@ -3955,7 +3955,7 @@ HInstruction* HUnaryMathOperation::New(
       case kMathFloor:
         return H_CONSTANT_DOUBLE(std::floor(d));
       case kMathClz32: {
-        uint32_t i = static_cast<uint32_t>(constant->Integer32Value());
+        uint32_t i = DoubleToUint32(d);
         return H_CONSTANT_INT(
             (i == 0) ? 32 : CompilerIntrinsics::CountLeadingZeros(i));
       }