glibc/sysdeps/arm/strlen.S
Zack Weinberg 81cb7a0b2b Remove sfi_* annotations from ARM assembly files.
This semi-mechanical patch removes all uses and definitions of the
sfi_breg, sfi_pld, and sfi_sp macros from various ARM-specific
assembly files.  These were only used by NaCl.

	* sysdeps/arm/sysdep.h
        (ARM_SFI_MACROS, sfi_breg, sfi_pld, sfi_sp): Delete definitions.

	* sysdeps/arm/__longjmp.S, sysdeps/arm/add_n.S
	* sysdeps/arm/addmul_1.S, sysdeps/arm/arm-mcount.S
	* sysdeps/arm/armv6/rawmemchr.S, sysdeps/arm/armv6/strchr.S
	* sysdeps/arm/armv6/strcpy.S, sysdeps/arm/armv6/strlen.S
	* sysdeps/arm/armv6/strrchr.S, sysdeps/arm/armv6t2/memchr.S
	* sysdeps/arm/armv6t2/strlen.S
	* sysdeps/arm/armv7/multiarch/memcpy_impl.S
	* sysdeps/arm/armv7/strcmp.S, sysdeps/arm/dl-tlsdesc.S
	* sysdeps/arm/memcpy.S, sysdeps/arm/memmove.S
	* sysdeps/arm/memset.S, sysdeps/arm/setjmp.S
	* sysdeps/arm/strlen.S, sysdeps/arm/submul_1.S:
        Remove all uses of sfi_breg, sfi_pld, and sfi_sp.
2017-05-20 08:12:11 -04:00

78 lines
3.0 KiB
ArmAsm

/* Copyright (C) 1998-2017 Free Software Foundation, Inc.
This file is part of the GNU C Library.
Code contributed by Matthew Wilcox <willy@odie.barnet.ac.uk>
The GNU C Library is free software; you can redistribute it and/or
modify it under the terms of the GNU Lesser General Public
License as published by the Free Software Foundation; either
version 2.1 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
Lesser General Public License for more details.
You should have received a copy of the GNU Lesser General Public
License along with the GNU C Library. If not, see
<http://www.gnu.org/licenses/>. */
/* Thumb requires excessive IT insns here. */
#define NO_THUMB
#include <sysdep.h>
/* size_t strlen(const char *S)
* entry: r0 -> string
* exit: r0 = len
*/
.syntax unified
.text
ENTRY(strlen)
bic r1, r0, $3 @ addr of word containing first byte
ldr r2, [r1], $4 @ get the first word
ands r3, r0, $3 @ how many bytes are duff?
rsb r0, r3, $0 @ get - that number into counter.
beq Laligned @ skip into main check routine if no
@ more
#ifdef __ARMEB__
orr r2, r2, $0xff000000 @ set this byte to non-zero
subs r3, r3, $1 @ any more to do?
orrgt r2, r2, $0x00ff0000 @ if so, set this byte
subs r3, r3, $1 @ more?
orrgt r2, r2, $0x0000ff00 @ then set.
#else
orr r2, r2, $0x000000ff @ set this byte to non-zero
subs r3, r3, $1 @ any more to do?
orrgt r2, r2, $0x0000ff00 @ if so, set this byte
subs r3, r3, $1 @ more?
orrgt r2, r2, $0x00ff0000 @ then set.
#endif
Laligned: @ here, we have a word in r2. Does it
tst r2, $0x000000ff @ contain any zeroes?
tstne r2, $0x0000ff00 @
tstne r2, $0x00ff0000 @
tstne r2, $0xff000000 @
addne r0, r0, $4 @ if not, the string is 4 bytes longer
ldrne r2, [r1], $4 @ and we continue to the next word
bne Laligned @
Llastword: @ drop through to here once we find a
#ifdef __ARMEB__
tst r2, $0xff000000 @ word that has a zero byte in it
addne r0, r0, $1 @
tstne r2, $0x00ff0000 @ and add up to 3 bytes on to it
addne r0, r0, $1 @
tstne r2, $0x0000ff00 @ (if first three all non-zero, 4th
addne r0, r0, $1 @ must be zero)
#else
tst r2, $0x000000ff @ word that has a zero byte in it
addne r0, r0, $1 @
tstne r2, $0x0000ff00 @ and add up to 3 bytes on to it
addne r0, r0, $1 @
tstne r2, $0x00ff0000 @ (if first three all non-zero, 4th
addne r0, r0, $1 @ must be zero)
#endif
DO_RET(lr)
END(strlen)
libc_hidden_builtin_def (strlen)