hg: jdk7/tl/jdk: 6642323: Speeding up Single Byte Decoders; ...

[Christian Thalinger]

On Sun, 2009-01-18 at 03:01 +0100, Ulf Zibis wrote:
> My results by JDK 1.7.0 ea b43 :
> 
> time for 1st warm up: 3091 ms
> time for 2nd warm up: 3100 ms
> time for map[a & 0xFF]: 7207 ms
> time for map[a + 0x80]: 7225 ms
> time for inlined map[a & 0xFF]: 8100 ms
> time for inlined map[a + 0x80]: 8084 ms

Vanilla HotSpot:

time for 1st warm up: 622 ms
time for 2nd warm up: 586 ms
time for map[a & 0xFF]: 1460 ms
time for map[a + 0x80]: 1456 ms
time for inlined map[a & 0xFF]: 1461 ms
time for inlined map[a + 0x80]: 1454 ms

Hotspot w/ unsigned-byte loads:

time for 1st warm up: 680 ms
time for 2nd warm up: 641 ms
time for map[a & 0xFF]: 1537 ms
time for map[a + 0x80]: 1468 ms
time for inlined map[a & 0xFF]: 1525 ms
time for inlined map[a + 0x80]: 1462 ms

For technical details I will reply on hotspot-compiler-dev.

-- Christian