From: Jan Beulich Date: Thu, 12 Mar 2009 10:47:13 +0000 (+0000) Subject: x86-64: remove unnecessary spill/reload of rbx from memcpy X-Git-Url: https://git.karo-electronics.de/?a=commitdiff_plain;h=dd1ef4ec4721ddc0a1f2b73a4f67930cb320665c;p=linux-beck.git x86-64: remove unnecessary spill/reload of rbx from memcpy Impact: micro-optimization This should slightly improve its performance. Signed-off-by: Jan Beulich LKML-Reference: <49B8F641.76E4.0078.0@novell.com> Signed-off-by: Ingo Molnar --- diff --git a/arch/x86/lib/memcpy_64.S b/arch/x86/lib/memcpy_64.S index c22981fa2f3a..10c067694af4 100644 --- a/arch/x86/lib/memcpy_64.S +++ b/arch/x86/lib/memcpy_64.S @@ -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)