From 534dfb536f19737f2642ee56dd67a97c5db6a74e Mon Sep 17 00:00:00 2001 From: Denis Vlasenko Date: Tue, 15 Apr 2008 08:23:19 +0000 Subject: amd64 string ops: replace some instructions by smaller ones, e.g. testb $0xff, %cl -> testb %cl, %cl --- libc/string/x86_64/strcspn.S | 7 +++---- 1 file changed, 3 insertions(+), 4 deletions(-) (limited to 'libc/string/x86_64/strcspn.S') diff --git a/libc/string/x86_64/strcspn.S b/libc/string/x86_64/strcspn.S index c02fbbb5f..9563de496 100644 --- a/libc/string/x86_64/strcspn.S +++ b/libc/string/x86_64/strcspn.S @@ -26,7 +26,6 @@ #include "_glibc_inc.h" /* Seems to be unrolled too much */ -/* (and why testb $0xff, %cl, not testb %cl, %cl?) */ /* BEWARE: `#ifdef strcspn' means that strcspn is redefined as `strpbrk' */ #define STRPBRK_P (defined strcspn) @@ -63,19 +62,19 @@ L(2): movb (%rax), %cl /* get byte from skipset */ movb %cl, (%rsp,%rcx) /* set corresponding byte in skipset table */ movb 1(%rax), %cl /* get byte from skipset */ - testb $0xff, %cl /* is NUL char? */ + testb %cl, %cl /* is NUL char? */ jz L(1) /* yes => start compare loop */ movb %cl, (%rsp,%rcx) /* set corresponding byte in skipset table */ movb 2(%rax), %cl /* get byte from skipset */ - testb $0xff, %cl /* is NUL char? */ + testb %cl, %cl /* is NUL char? */ jz L(1) /* yes => start compare loop */ movb %cl, (%rsp,%rcx) /* set corresponding byte in skipset table */ movb 3(%rax), %cl /* get byte from skipset */ addq $4, %rax /* increment skipset pointer */ movb %cl, (%rsp,%rcx) /* set corresponding byte in skipset table */ - testb $0xff, %cl /* is NUL char? */ + testb %cl, %cl /* is NUL char? */ jnz L(2) /* no => process next dword from skipset */ L(1): leaq -4(%rdx), %rax /* prepare loop */ -- cgit v1.2.3