Smaller in only the upper bound? I would an explicit upper bounds check would
dominate that of the bounds check for the array itself.
Paul.
> On Jan 29, 2018, at 11:37 AM, Claes Redestad <claes.redes...@oracle.com>
> wrote:
>
> I ran with a smaller byte[] initially and saw about a 10% improvement from
> removing the branch, which is why I felt the superfluous bytes were motivated.
>
> /Claes
>
> Paul Sandoz <paul.san...@oracle.com> skrev: (29 januari 2018 19:14:44 CET)
>
>
> On Jan 29, 2018, at 9:44 AM, Martin Buchholz <marti...@google.com> wrote:
>
> Thanks. I might try to shrink the size of the static array, by only
> storing values between '0' and 'z', at the cost of slightly greater lookup
> costs for each char.
>
>
> I was wondering the same, or just clip the end of the array to’z'
>
> if (ch <= ‘z’ && radix …) { // Might even fold the upper bounds check for
> DIGITS
> value = DIGITS[ch];
> ...
> }
>
> Paul.
>
> On Mon, Jan 29, 2018 at 3:15 AM, Claes Redestad <claes.redes...@oracle.com>
> wrote:
>
> Hi,
>
> for the latin1 block of CharacterData we can improve the
> digit(int, int) implementation by providing an optimized lookup
> table. This improves microbenchmarks exercising Integer.parseInt,
> Long.parseLong and UUID.fromString etc by around 50%for typical
> inputs.
>
> Webrev: http://cr.openjdk.java.net/~redestad/8196331/open.00/
> <http://cr.openjdk.java.net/~redestad/8196331/open.00/>
> Bug: https://bugs.openjdk.java.net/browse/JDK-8196331
> <https://bugs.openjdk.java.net/browse/JDK-8196331>
>
> The lookup array is pre-calculated to minimize startup impact
> (adds 1,027 bytecodes executed during initialization)
>
> /Claes
>
>
>
> --
> Sent from my Android device with K-9 Mail. Please excuse my brevity.
