tree 3c159d2ca6f967fca13bae17cff19f92e0b3896c
parent 72083646528d4887b920deb71b37e09bc7d227bb
author Anton Blanchard <anton@samba.org> 1281630489 +0000
committer Benjamin Herrenschmidt <benh@kernel.crashing.org> 1291006097 +1100

powerpc: Add support for popcnt instructions

POWER5 added popcntb, and POWER7 added popcntw and popcntd. As a first step
this patch does all the work out of line, but it would be nice to implement
them as inlines with an out of line fallback.

The performance issue with hweight was noticed when disabling SMT on a large
(192 thread) POWER7 box. The patch improves that testcase by about 8%.

Signed-off-by: Anton Blanchard <anton@samba.org>
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>