Fix Number.MIN_VALUE when denormal support is disabled for the CPU

JavaScriptCore/runtime/NumberConstructor.cpp

@@ -60,6 +60,8 @@ NumberConstructor::NumberConstructor(VM& vm, Structure* structure)
 {
 }
 
+static double MinValueAccountingForDenormals = DBL_MIN;
+
 void NumberConstructor::finishCreation(VM& vm, NumberPrototype* numberPrototype)
 {
  Base::finishCreation(vm, NumberPrototype::info()->className);
@@ -70,6 +72,14 @@ void NumberConstructor::finishCreation(VM& vm, NumberPrototype* numberPrototype)
 
  // no. of arguments for constructor
  putDirectWithoutTransition(vm, vm.propertyNames->length, jsNumber(1), ReadOnly | DontEnum | DontDelete);
+
+ // Test for denormal support. Use 5E-324 as MIN_VALUE if we have denormals
+ // Careful: this test gets easily optimized away by the compiler, hence
+ // the assignment to another var.
+ double denormalTest = MinValueAccountingForDenormals / 2;
+ if( denormalTest != 0 ) {
+ MinValueAccountingForDenormals = 5E-324;
+ }
 }
 
 bool NumberConstructor::getOwnPropertySlot(JSObject* object, ExecState* exec, PropertyName propertyName, PropertySlot& slot)
@@ -104,7 +114,7 @@ static JSValue numberConstructorMaxValue(ExecState*, JSValue, PropertyName)
 
 static JSValue numberConstructorMinValue(ExecState*, JSValue, PropertyName)
 {
- return jsNumber(5E-324);
+ return jsNumber(MinValueAccountingForDenormals);
 }
 
 // ECMA 15.7.1