[POWERPC] system call micro optimisation

In the syscall path we currently have:

       crclr   so
       mfcr    r9

If we shift the crclr up we can avoid a stall on some CPUs.

Signed-off-by: Anton Blanchard <anton@samba.org>
Signed-off-by: Paul Mackerras <paulus@samba.org>
This commit is contained in:
Anton Blanchard 2006-06-11 01:15:55 +10:00 committed by Paul Mackerras
parent 9e6e3c2c79
commit bd19c8994a

View File

@ -57,6 +57,7 @@ system_call_common:
beq- 1f
ld r1,PACAKSAVE(r13)
1: std r10,0(r1)
crclr so
std r11,_NIP(r1)
std r12,_MSR(r1)
std r0,GPR0(r1)
@ -75,7 +76,6 @@ system_call_common:
std r11,GPR11(r1)
std r11,GPR12(r1)
std r9,GPR13(r1)
crclr so
mfcr r9
mflr r10
li r11,0xc01