Branching takes two cycles on MPC8xx. Lets duplicate the two instructions and avoid the branching.
Signed-off-by: Christophe Leroy <[email protected]> --- 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 -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to [email protected] More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/
