diff options
Diffstat (limited to 'sysdeps/i386/i486/strlen.S')
| -rw-r--r-- | sysdeps/i386/i486/strlen.S | 86 |
1 files changed, 43 insertions, 43 deletions
diff --git a/sysdeps/i386/i486/strlen.S b/sysdeps/i386/i486/strlen.S index a92067ab41..4a25011016 100644 --- a/sysdeps/i386/i486/strlen.S +++ b/sysdeps/i386/i486/strlen.S @@ -1,23 +1,23 @@ /* strlen(str) -- determine the length of the string STR. -Optimized for Intel 80x86, x>=4. -Copyright (C) 1991, 92, 93, 94, 95, 96 Free Software Foundation, Inc. -Contributed by Ulrich Drepper <drepper@gnu.ai.mit.edu>. -This file is part of the GNU C Library. - -The GNU C Library is free software; you can redistribute it and/or -modify it under the terms of the GNU Library General Public License as -published by the Free Software Foundation; either version 2 of the -License, or (at your option) any later version. - -The GNU C Library is distributed in the hope that it will be useful, -but WITHOUT ANY WARRANTY; without even the implied warranty of -MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU -Library General Public License for more details. - -You should have received a copy of the GNU Library General Public -License along with the GNU C Library; see the file COPYING.LIB. If -not, write to the Free Software Foundation, Inc., 59 Temple Place - Suite 330, -Boston, MA 02111-1307, USA. */ + Optimized for Intel 80x86, x>=4. + Copyright (C) 1991, 92, 93, 94, 95, 96, 97 Free Software Foundation, Inc. + Contributed by Ulrich Drepper <drepper@gnu.ai.mit.edu>. + This file is part of the GNU C Library. + + The GNU C Library is free software; you can redistribute it and/or + modify it under the terms of the GNU Library General Public License as + published by the Free Software Foundation; either version 2 of the + License, or (at your option) any later version. + + The GNU C Library is distributed in the hope that it will be useful, + but WITHOUT ANY WARRANTY; without even the implied warranty of + MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU + Library General Public License for more details. + + You should have received a copy of the GNU Library General Public + License along with the GNU C Library; see the file COPYING.LIB. If not, + write to the Free Software Foundation, Inc., 59 Temple Place - Suite 330, + Boston, MA 02111-1307, USA. */ #include <sysdep.h> #include "asm-syntax.h" @@ -33,21 +33,21 @@ ENTRY (strlen) movl %ecx, %eax /* duplicate it */ andl $3, %ecx /* mask alignment bits */ - jz L1 /* aligned => start loop */ + jz L(1) /* aligned => start loop */ cmpb %ch, (%eax) /* is byte NUL? */ - je L2 /* yes => return */ + je L(2) /* yes => return */ incl %eax /* increment pointer */ xorl $3, %ecx /* was alignment = 3? */ - jz L1 /* yes => now it is aligned and start loop */ + jz L(1) /* yes => now it is aligned and start loop */ cmpb %ch, (%eax) /* is byte NUL? */ - je L2 /* yes => return */ + je L(2) /* yes => return */ addl $1, %eax /* increment pointer */ subl $1, %ecx /* was alignment = 2? */ - jz L1 /* yes => now it is aligned and start loop */ + jz L(1) /* yes => now it is aligned and start loop */ cmpb %ch, (%eax) /* is byte NUL? */ - je L2 /* yes => return */ + je L(2) /* yes => return */ /* Don't change the above `addl $1,%eax' and `subl $1, %ecx' into `incl %eax' and `decl %ecx' resp. The additional two byte per instruction make the @@ -61,73 +61,73 @@ ENTRY (strlen) subl $15, %eax /* effectively +1 */ -L4: addl $16, %eax /* adjust pointer for full loop */ +L(4): addl $16, %eax /* adjust pointer for full loop */ -L1: movl (%eax), %ecx /* get word (= 4 bytes) in question */ +L(1): movl (%eax), %ecx /* get word (= 4 bytes) in question */ movl $0xfefefeff, %edx /* magic value */ addl %ecx, %edx /* add the magic value to the word. We get carry bits reported for each byte which is *not* 0 */ - jnc L3 /* highest byte is NUL => return pointer */ + jnc L(3) /* highest byte is NUL => return pointer */ xorl %ecx, %edx /* (word+magic)^word */ orl $0xfefefeff, %edx /* set all non-carry bits */ incl %edx /* add 1: if one carry bit was *not* set the addition will not result in 0. */ - jnz L3 /* found NUL => return pointer */ + jnz L(3) /* found NUL => return pointer */ movl 4(%eax), %ecx /* get word (= 4 bytes) in question */ movl $0xfefefeff, %edx /* magic value */ addl %ecx, %edx /* add the magic value to the word. We get carry bits reported for each byte which is *not* 0 */ - jnc L5 /* highest byte is NUL => return pointer */ + jnc L(5) /* highest byte is NUL => return pointer */ xorl %ecx, %edx /* (word+magic)^word */ orl $0xfefefeff, %edx /* set all non-carry bits */ incl %edx /* add 1: if one carry bit was *not* set the addition will not result in 0. */ - jnz L5 /* found NUL => return pointer */ + jnz L(5) /* found NUL => return pointer */ movl 8(%eax), %ecx /* get word (= 4 bytes) in question */ movl $0xfefefeff, %edx /* magic value */ addl %ecx, %edx /* add the magic value to the word. We get carry bits reported for each byte which is *not* 0 */ - jnc L6 /* highest byte is NUL => return pointer */ + jnc L(6) /* highest byte is NUL => return pointer */ xorl %ecx, %edx /* (word+magic)^word */ orl $0xfefefeff, %edx /* set all non-carry bits */ incl %edx /* add 1: if one carry bit was *not* set the addition will not result in 0. */ - jnz L6 /* found NUL => return pointer */ + jnz L(6) /* found NUL => return pointer */ movl 12(%eax), %ecx /* get word (= 4 bytes) in question */ movl $0xfefefeff, %edx /* magic value */ addl %ecx, %edx /* add the magic value to the word. We get carry bits reported for each byte which is *not* 0 */ - jnc L7 /* highest byte is NUL => return pointer */ + jnc L(7) /* highest byte is NUL => return pointer */ xorl %ecx, %edx /* (word+magic)^word */ orl $0xfefefeff, %edx /* set all non-carry bits */ incl %edx /* add 1: if one carry bit was *not* set the addition will not result in 0. */ - jz L4 /* no NUL found => continue loop */ + jz L(4) /* no NUL found => continue loop */ -L7: addl $4, %eax /* adjust pointer */ -L6: addl $4, %eax -L5: addl $4, %eax +L(7): addl $4, %eax /* adjust pointer */ +L(6): addl $4, %eax +L(5): addl $4, %eax -L3: testb %cl, %cl /* is first byte NUL? */ - jz L2 /* yes => return */ +L(3): testb %cl, %cl /* is first byte NUL? */ + jz L(2) /* yes => return */ incl %eax /* increment pointer */ testb %ch, %ch /* is second byte NUL? */ - jz L2 /* yes => return */ + jz L(2) /* yes => return */ incl %eax /* increment pointer */ testl $0xff0000, %ecx /* is third byte NUL? */ - jz L2 /* yes => return pointer */ + jz L(2) /* yes => return pointer */ incl %eax /* increment pointer */ -L2: subl 4(%esp), %eax /* compute difference to string start */ +L(2): subl 4(%esp), %eax /* compute difference to string start */ ret END (strlen) |