Messages in this thread Patch in this message | | | From | Christophe Leroy <> | Subject | [PATCH v2 10/19] powerpc/8xx: Duplicate two insns instead of branching | Date | Fri, 29 Aug 2014 11:14:39 +0200 (CEST) |
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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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