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Subject[PATCH v2 10/19] powerpc/8xx: Duplicate two insns instead of branching
Date
Branching takes two cycles on MPC8xx. Lets duplicate the two instructions
and avoid the branching.

Signed-off-by: Christophe Leroy <christophe.leroy@c-s.fr>

---
arch/powerpc/kernel/head_8xx.S | 6 ++++--
1 files changed, 4 insertions(+), 2 deletions(-)

diff --git a/arch/powerpc/kernel/head_8xx.S b/arch/powerpc/kernel/head_8xx.S
index 5037420..4a49ff3 100644
--- a/arch/powerpc/kernel/head_8xx.S
+++ b/arch/powerpc/kernel/head_8xx.S
@@ -638,9 +638,11 @@ modified_instr:

/* special handling for r10,r11 since these are modified already */
153: mfspr r11, SPRN_SPRG_SCRATCH1 /* load r11 from SPRN_SPRG_SCRATCH1 */
- b 155f
+ add r10, r10, r11 /* add it */
+ mfctr r11 /* restore r11 */
+ b 151b
154: mfspr r11, SPRN_SPRG_SCRATCH0 /* load r10 from SPRN_SPRG_SCRATCH0 */
-155: add r10, r10, r11 /* add it */
+ add r10, r10, r11 /* add it */
mfctr r11 /* restore r11 */
b 151b
#endif
--
1.7.1


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