On the 0x5A4 day of Apache Harmony Tim Ellison wrote:
> /**
> @@ -402,25 +384,31 @@
> * @since 1.4
> */
> public static int compare(float float1, float float2) {
> - int f1, f2;
> - int NaNbits = Float.floatToIntBits(Float.NaN);
> - if ((f1 = Float.floatToIntBits(float1)) == NaNbits) {
> - if (Float.floatToIntBits(float2) == NaNbits) {
> - return 0;
> - }
> +
> + if (float1 > float2) {
> return 1;
> }
> - if ((f2 = Float.floatToIntBits(float2)) == NaNbits) {
> + if (float2 > float1) {
> return -1;
> }
> - if (float1 == float2) {
> - if (f1 == f2) {
> +
> + int f1 = floatToRawIntBits(float1);
> + int f2 = floatToRawIntBits(float2);
> + if (f1 == f2) {
> + return 0;
> + }
I'd suggest a slightly different code path: move native calls further
below. floatToRawIntBits() is *very* slow and only useful for -0f
checking. Hitting two zeroes is less likely than hitting a NaN IMHO.
Should look like this:
// Non-zero and non-NaN equality checking.
if (float1 == float2 && (0.0f != float1 || 0.0f != float2)) {
return 0;
}
// NaNs are equal to other NaNs and larger than any other float.
[...]
// Sort out zeroes.
int f1 = floatToRawIntBits(float1);
int f2 = floatToRawIntBits(float2);
[...]
> +
> + // NaNs are equal to other NaNs and larger than any other float
> + if (isNaN(float1)) {
> + if (isNaN(float2)) {
> return 0;
> }
> - // check for -0
> - return f1 > f2 ? 1 : -1;
> + return 1;
> + } else if (isNaN(float2)) {
> + return -1;
> }
> - return float1 > float2 ? 1 : -1;
> +
> + return (f1 < f2) ? -1 : 1;
> }
>
> /**
>
--
Egor Pasko
