x86-64: remove unnecessary spill/reload of rbx from memcpy

Impact: micro-optimization

This should slightly improve its performance.

Signed-off-by: Jan Beulich <jbeulich@novell.com>
LKML-Reference: <49B8F641.76E4.0078.0@novell.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
This commit is contained in:
Jan Beulich 2009-03-12 10:47:13 +00:00 committed by Ingo Molnar
parent c2810188c1
commit dd1ef4ec47

View File

@ -33,9 +33,6 @@ ENDPROC(memcpy_c)
ENTRY(__memcpy)
ENTRY(memcpy)
CFI_STARTPROC
pushq %rbx
CFI_ADJUST_CFA_OFFSET 8
CFI_REL_OFFSET rbx, 0
movq %rdi,%rax
movl %edx,%ecx
@ -102,11 +99,7 @@ ENTRY(memcpy)
jnz .Lloop_1
.Lende:
popq %rbx
CFI_ADJUST_CFA_OFFSET -8
CFI_RESTORE rbx
ret
.Lfinal:
CFI_ENDPROC
ENDPROC(memcpy)
ENDPROC(__memcpy)