This patch adds a few optimisations in memcpy functions by using
lbzu/stbu instead of lxb/stb and by re-ordering insn inside a loop
to reduce latency due to loading
Signed-off-by: Christophe Leroy <christophe.le...@c-s.fr>
---
arch/powerpc/lib/copy_32.S | 10 +++++-----
1 file changed, 5 insertions(+), 5 deletions(-)
diff --git a/arch/powerpc/lib/copy_32.S b/arch/powerpc/lib/copy_32.S
index 1d49c74..2ef50c6 100644
--- a/arch/powerpc/lib/copy_32.S
+++ b/arch/powerpc/lib/copy_32.S
@@ -155,9 +155,9 @@ _GLOBAL(memcpy)
mtctr r8
beq+ 61f
70: lbz r9,4(r4) /* do some bytes */
- stb r9,4(r6)
addi r4,r4,1
addi r6,r6,1
+ stb r9,3(r6)
bdnz 70b
61: srwi. r0,r0,2
mtctr r0
@@ -199,10 +199,10 @@ _GLOBAL(memcpy)
64: andi. r0,r5,3
mtctr r0
beq+ 65f
-40: lbz r0,4(r4)
- stb r0,4(r6)
- addi r4,r4,1
- addi r6,r6,1
+ addi r4,r4,3
+ addi r6,r6,3
+40: lbzu r0,1(r4)
+ stbu r0,1(r6)
bdnz 40b
65: blr
--
2.1.0
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