diff options
Diffstat (limited to 'sysdeps/i386/i586/strlen.S')
| -rw-r--r-- | sysdeps/i386/i586/strlen.S | 45 |
1 files changed, 23 insertions, 22 deletions
diff --git a/sysdeps/i386/i586/strlen.S b/sysdeps/i386/i586/strlen.S index e8fb916812..2e6ea680ec 100644 --- a/sysdeps/i386/i586/strlen.S +++ b/sysdeps/i386/i586/strlen.S @@ -1,6 +1,6 @@ /* strlen -- Compute length og NUL terminated string. Highly optimized version for ix86, x>=5. - Copyright (C) 1995, 1996 Free Software Foundation, Inc. + Copyright (C) 1995, 1996, 1997 Free Software Foundation, Inc. This file is part of the GNU C Library. Contributed by Ulrich Drepper, <drepper@gnu.ai.mit.edu>. @@ -20,6 +20,7 @@ Boston, MA 02111-1307, USA. */ #include <sysdep.h> +#include "asm-syntax.h" /* This version is especially optimized for the i586 (and following?) processors. This is mainly done by using the two pipelines. The @@ -46,24 +47,24 @@ ENTRY(strlen) andl %eax, %edx /* separate last two bits of address */ - jz L1 /* aligned => start loop */ - jp L0 /* exactly two bits set */ + jz L(1) /* aligned => start loop */ + jp L(0) /* exactly two bits set */ cmpb %dh, (%eax) /* is byte NUL? */ - je L2 /* yes => return */ + je L(2) /* yes => return */ incl %eax /* increment pointer */ cmpb %dh, (%eax) /* is byte NUL? */ - je L2 /* yes => return */ + je L(2) /* yes => return */ incl %eax /* increment pointer */ xorl $2, %edx - jz L1 + jz L(1) -L0: cmpb %dh, (%eax) /* is byte NUL? */ - je L2 /* yes => return */ +L(0): cmpb %dh, (%eax) /* is byte NUL? */ + je L(2) /* yes => return */ incl %eax /* increment pointer */ xorl %edx, %edx /* We need %edx == 0 for later */ @@ -91,7 +92,7 @@ L0: cmpb %dh, (%eax) /* is byte NUL? */ Note: %edx == 0 in any case here. */ -L1: +L(1): movl (%eax), %ecx /* get word (= 4 bytes) in question */ addl $4, %eax /* adjust pointer for *next* word */ @@ -99,13 +100,13 @@ L1: addl $magic, %ecx /* add magic word */ decl %edx /* complete negation of word */ - jnc L3 /* previous addl caused overflow? */ + jnc L(3) /* previous addl caused overflow? */ xorl %ecx, %edx /* (word+magic)^word */ andl $~magic, %edx /* any of the carry flags set? */ - jne L3 /* yes => determine byte */ + jne L(3) /* yes => determine byte */ movl (%eax), %ecx /* get word (= 4 bytes) in question */ @@ -115,13 +116,13 @@ L1: addl $magic, %ecx /* add magic word */ decl %edx /* complete negation of word */ - jnc L3 /* previous addl caused overflow? */ + jnc L(3) /* previous addl caused overflow? */ xorl %ecx, %edx /* (word+magic)^word */ andl $~magic, %edx /* any of the carry flags set? */ - jne L3 /* yes => determine byte */ + jne L(3) /* yes => determine byte */ movl (%eax), %ecx /* get word (= 4 bytes) in question */ @@ -131,13 +132,13 @@ L1: addl $magic, %ecx /* add magic word */ decl %edx /* complete negation of word */ - jnc L3 /* previous addl caused overflow? */ + jnc L(3) /* previous addl caused overflow? */ xorl %ecx, %edx /* (word+magic)^word */ andl $~magic, %edx /* any of the carry flags set? */ - jne L3 /* yes => determine byte */ + jne L(3) /* yes => determine byte */ movl (%eax), %ecx /* get word (= 4 bytes) in question */ @@ -147,35 +148,35 @@ L1: addl $magic, %ecx /* add magic word */ decl %edx /* complete negation of word */ - jnc L3 /* previous addl caused overflow? */ + jnc L(3) /* previous addl caused overflow? */ xorl %ecx, %edx /* (word+magic)^word */ andl $~magic, %edx /* any of the carry flags set? */ - je L1 /* no => start loop again */ + je L(1) /* no => start loop again */ -L3: subl $4, %eax /* correct too early pointer increment */ +L(3): subl $4, %eax /* correct too early pointer increment */ subl $magic, %ecx cmpb $0, %cl /* lowest byte NUL? */ - jz L2 /* yes => return */ + jz L(2) /* yes => return */ inc %eax /* increment pointer */ testb %ch, %ch /* second byte NUL? */ - jz L2 /* yes => return */ + jz L(2) /* yes => return */ shrl $16, %ecx /* make upper bytes accessible */ incl %eax /* increment pointer */ cmpb $0, %cl /* is third byte NUL? */ - jz L2 /* yes => return */ + jz L(2) /* yes => return */ incl %eax /* increment pointer */ -L2: subl 4(%esp), %eax /* now compute the length as difference +L(2): subl 4(%esp), %eax /* now compute the length as difference between start and terminating NUL character */ |