Add signMask getter to Float32x4

runtime/lib/simd128.cc

Index: runtime/lib/simd128.cc
diff --git a/runtime/lib/simd128.cc b/runtime/lib/simd128.cc
index 0ff6da47c1f7d238c9c580e07e17804d29b9f1ac..9a9791ab7cdbdbb384e27db15381f55438f9437b 100644
--- a/runtime/lib/simd128.cc
+++ b/runtime/lib/simd128.cc
@@ -229,6 +229,17 @@ DEFINE_NATIVE_ENTRY(Float32x4_getW, 1) {
 }
 
 
+DEFINE_NATIVE_ENTRY(Float32x4_getSignMask, 1) {
+  GET_NON_NULL_NATIVE_ARGUMENT(Float32x4, self, arguments->NativeArgAt(0));
+  uint32_t mx = (bit_cast<uint32_t>(self.x()) & 0x80000000) >> 31;
+  uint32_t my = (bit_cast<uint32_t>(self.y()) & 0x80000000) >> 31;
+  uint32_t mz = (bit_cast<uint32_t>(self.z()) & 0x80000000) >> 31;
+  uint32_t mw = (bit_cast<uint32_t>(self.w()) & 0x80000000) >> 31;
+  uint32_t value = mx | (my << 1) | (mz << 2) | (mw << 3);
+  return Integer::New(value);
+}
+
+
 DEFINE_NATIVE_ENTRY(Float32x4_shuffle, 2) {
   GET_NON_NULL_NATIVE_ARGUMENT(Float32x4, self, arguments->NativeArgAt(0));
   GET_NON_NULL_NATIVE_ARGUMENT(Integer, mask, arguments->NativeArgAt(1));