Le 26/05/2016 à 21:37, Segher Boessenkool a écrit :
On Thu, May 26, 2016 at 09:24:51AM +0200, Christophe Leroy wrote:
Wouldn't it be better to add nops before the function entry in order to
get the hot loop aligned, instead of adding nops in the middle of the
function ?
Why would that be better? The nops are executed once per function call
in either case, there are the same number of nops in either case, and
on most CPUs nops aren't actually executed anyway (they are decoded and
the thrown away).
The idea was to not execute them:
|.balign 16 nop nop _GLOBAL(strcpy) addi r5,r3,-1 addi r4,r4,-1 1: lbzu
r0,1(r4) cmpwi 0,r0,0 stbu r0,1(r5) bne 1b blr |
Christophe
_______________________________________________
Linuxppc-dev mailing list
Linuxppc-dev@lists.ozlabs.org
https://lists.ozlabs.org/listinfo/linuxppc-dev
