diff --git a/Source/JavaScriptCore/runtime/MathCommon.h b/Source/JavaScriptCore/runtime/MathCommon.h
index b049b32a1ef6..10204adb4461 100644
--- a/Source/JavaScriptCore/runtime/MathCommon.h
+++ b/Source/JavaScriptCore/runtime/MathCommon.h
@@ -182,6 +182,12 @@ ALWAYS_INLINE int32_t toInt32(double number)
     int32_t result = 0;
     __asm__ ("fjcvtzs %w0, %d1" : "=r" (result) : "w" (number) : "cc");
     return result;
+#elif CPU(X86_64) && COMPILER(GCC_COMPATIBLE)
+    int32_t result;
+    __asm__ ("cvttsd2si %1, %0" : "=r" (result) : "x" (number));
+    if (static_cast<double>(result) != number)
+        return toIntImpl<int32_t>(number);
+    return result;
 #else
     return toIntImpl<int32_t>(number);
 #endif
diff --git a/Source/JavaScriptCore/runtime/TypedArrayAdaptors.h b/Source/JavaScriptCore/runtime/TypedArrayAdaptors.h
index b6c443ca1833..4dd85f48d8b1 100644
--- a/Source/JavaScriptCore/runtime/TypedArrayAdaptors.h
+++ b/Source/JavaScriptCore/runtime/TypedArrayAdaptors.h
@@ -68,14 +68,7 @@ struct IntegralTypedArrayAdaptor {
     
     static Type toNativeFromDouble(double value)
     {
-#if HAVE(FJCVTZS_INSTRUCTION)
         return static_cast<Type>(toInt32(value));
-#else
-        int32_t result = static_cast<int32_t>(value);
-        if (static_cast<double>(result) != value)
-            result = toInt32(value);
-        return static_cast<Type>(result);
-#endif
     }
 
     static constexpr Type toNativeFromUndefined()