84d9c625bf
- Fix for possible unset uid/gid in toproto
- Fix for default mtree style
- Update libelf
- Importing libexecinfo
- Resynchronize GCC, mpc, gmp, mpfr
- build.sh: Replace params with show-params.
This has been done as the make target has been renamed in the same
way, while a new target named params has been added. This new
target generates a file containing all the parameters, instead of
printing it on the console.
- Update test48 with new etc/services (Fix by Ben Gras <ben@minix3.org)
get getservbyport() out of the inner loop
Change-Id: Ie6ad5226fa2621ff9f0dee8782ea48f9443d2091
528 lines
18 KiB
ArmAsm
528 lines
18 KiB
ArmAsm
/*-
|
|
* Copyright (c) 2013 The NetBSD Foundation, Inc.
|
|
* All rights reserved.
|
|
*
|
|
* This code is derived from software contributed to The NetBSD Foundation
|
|
* by Matt Thomas of 3am Software Foundry.
|
|
*
|
|
* Redistribution and use in source and binary forms, with or without
|
|
* modification, are permitted provided that the following conditions
|
|
* are met:
|
|
* 1. Redistributions of source code must retain the above copyright
|
|
* notice, this list of conditions and the following disclaimer.
|
|
* 2. Redistributions in binary form must reproduce the above copyright
|
|
* notice, this list of conditions and the following disclaimer in the
|
|
* documentation and/or other materials provided with the distribution.
|
|
*
|
|
* THIS SOFTWARE IS PROVIDED BY THE NETBSD FOUNDATION, INC. AND CONTRIBUTORS
|
|
* ``AS IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED
|
|
* TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
|
|
* PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE FOUNDATION OR CONTRIBUTORS
|
|
* BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
|
|
* CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
|
|
* SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
|
|
* INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
|
|
* CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
|
|
* ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
|
|
* POSSIBILITY OF SUCH DAMAGE.
|
|
*/
|
|
|
|
#include <machine/asm.h>
|
|
|
|
RCSID("$NetBSD: strcpy_arm.S,v 1.3 2013/08/11 04:56:32 matt Exp $")
|
|
|
|
#ifdef STRLCPY
|
|
#ifdef _LIBC
|
|
WEAK_ALIAS(strlcpy, _strlcpy)
|
|
#endif
|
|
#define FUNCNAME strlcpy
|
|
#elif defined(STRNCPY)
|
|
#define FUNCNAME strncpy
|
|
#else
|
|
#define FUNCNAME strcpy
|
|
#endif
|
|
|
|
#ifdef _LIBC
|
|
#include "namespace.h"
|
|
#endif
|
|
|
|
#ifdef __ARMEL__
|
|
#define lslo lsr /* shift to lower address */
|
|
#define lshi lsl /* shift to higher address */
|
|
#define BYTE0 0x000000ff
|
|
#define BYTE1 0x0000ff00
|
|
#define BYTE2 0x00ff0000
|
|
#define BYTE3 0xff000000
|
|
#else
|
|
#define lslo lsl /* shift to lower address */
|
|
#define lshi lsr /* shift to higher address */
|
|
#define BYTE0 0xff000000
|
|
#define BYTE1 0x00ff0000
|
|
#define BYTE2 0x0000ff00
|
|
#define BYTE3 0x000000ff
|
|
#endif
|
|
|
|
/*
|
|
* On armv6 and later, to quickly determine if a word contains a NUL (0) byte,
|
|
* we add 254 to each byte using the UQADD8 (unsigned saturating add 8)
|
|
* instruction. For every non-NUL byte, the result for that byte will become
|
|
* 255. For NUL, it will be 254. When we complement the result of all 4 adds,
|
|
* if the result is non-0 then we must have encountered a NUL.
|
|
*
|
|
* For earlier architecture, we just use tst on all 4 bytes. There are other
|
|
* algorithms to detect NULs but they take longer and use more instructions.
|
|
*/
|
|
|
|
/*
|
|
* char *strcpy(char *dst, const char *src);
|
|
* char *strncpy(char *dst, const char *src, size_t len);
|
|
* size_t strlcpy(char *dst, const char *src, size_t len);
|
|
*/
|
|
|
|
.text
|
|
ENTRY(FUNCNAME)
|
|
#if defined(STRLCPY)
|
|
cmp r2, #1 /* is length 1 or less? */
|
|
bhi 1f /* no, do normal */
|
|
moveq r3, #0 /* = 1? load NUL */
|
|
strbeq r3, [r0] /* = 1? write NUL to dst */
|
|
mov r0, r1 /* move src to r0 */
|
|
b PLT_SYM(_C_LABEL(strlen)) /* and tailcall strlen */
|
|
1:
|
|
sub r2, r2, #1 /* leave one byte for NUL */
|
|
#endif
|
|
#if defined(STRNCPY)
|
|
cmp r2, #0 /* 0 length? */
|
|
RETc(eq) /* yes, just return */
|
|
#endif
|
|
push {r4-r9} /* save some registers */
|
|
#ifdef _ARM_ARCH_6
|
|
#ifdef _ARM_ARCH_7
|
|
movw r7, #0xfefe /* magic constant; 254 in each byte */
|
|
#else
|
|
mov r7, #0xfe /* put 254 in low byte */
|
|
orr r7, r7, r7, lsl #8 /* move to next byte */
|
|
#endif
|
|
orr r7, r7, r7, lsl #16 /* move to next halfword */
|
|
#endif
|
|
|
|
#if defined(STRLCPY)
|
|
add r6, r1, #1 /* save for return (deal with NUL) */
|
|
#else
|
|
mov r6, r0 /* save for return */
|
|
#endif
|
|
|
|
.Ldst_align:
|
|
tst r0, #3 /* check for dst alignment */
|
|
beq .Ldst_aligned /* ok, proceed to next check */
|
|
ldrb r5, [r1], #1 /* load a byte */
|
|
#if defined(STRNCPY)
|
|
subs r2, r2, #1 /* subtract out from count */
|
|
bmi .Ldst_full /* zero? the dst has no more room */
|
|
#endif
|
|
strb r5, [r0], #1 /* store a byte */
|
|
teq r5, #0 /* was it a NUL? */
|
|
beq .Lend_of_string /* yes, we are done */
|
|
#if defined(STRLCPY)
|
|
subs r2, r2, #1 /* subtract one from count */
|
|
strbeq r2, [r0], #1 /* zero? write trailing NUL */
|
|
beq .Ldst_full /* zero? the dst has no more room */
|
|
#endif
|
|
b .Ldst_align /* loop around for next byte */
|
|
.Ldst_aligned:
|
|
tst r1, #3 /* get the misalignment of src */
|
|
bne .Lincongruent /* !=? incongruent (slower) */
|
|
|
|
/* =? congruent (faster) */
|
|
|
|
.Lcongruent:
|
|
#if defined(STRLCPY)
|
|
add r6, r6, #3 /* compensate for word post-inc */
|
|
#endif
|
|
b .Lcongruent_mainloop_load
|
|
.Lcongruent_mainloop:
|
|
#if defined(STRLCPY) || defined(STRNCPY)
|
|
subs r2, r2, #4 /* subtract 4 from the count */
|
|
bmi .Lno_more_room
|
|
#endif
|
|
str r5, [r0], #4 /* store word into dst */
|
|
#if defined(STRLCPY)
|
|
beq .Lno_more_room /* count is 0? no room in dst */
|
|
#endif
|
|
#if defined(STRNCPY)
|
|
beq .Ldst_full_word_aligned /* count is 0? no room in dst */
|
|
#endif
|
|
.Lcongruent_mainloop_load:
|
|
ldr r5, [r1], #4 /* load word from source */
|
|
#if defined(_ARM_ARCH_6)
|
|
uqadd8 r3, r5, r7 /* magic happens here */
|
|
mvns r3, r3 /* is the complemented result 0? */
|
|
beq .Lcongruent_mainloop /* yes, no NULs, do it again */
|
|
#else
|
|
tst r5, #BYTE0 /* does byte 0 contain a NUL? */
|
|
tstne r5, #BYTE1 /* no, does byte 1 contain a NUL? */
|
|
tstne r5, #BYTE2 /* no, does byte 2 contain a NUL? */
|
|
tstne r5, #BYTE3 /* no, does byte 3 contain a NUL? */
|
|
bne .Lcongruent_mainloop /* yes, no NULs, do it again */
|
|
#endif
|
|
#if defined(STRLCPY) && 0
|
|
sub r1, r1, #3 /* back up src pointer */
|
|
#endif
|
|
#if defined(_ARM_ARCH_6)
|
|
#ifdef __ARMEL__
|
|
rev r3, r3 /* CLZ needs BE data */
|
|
#endif
|
|
clz r3, r3 /* count leading zeros */
|
|
#else
|
|
mov r3, #0 /* assume NUL is in byte 0 */
|
|
tst r5, #BYTE0 /* is NUL in byte 2? */
|
|
beq .Lcongruent_last_bytes /* yes, done searching. */
|
|
mov r3, #8 /* assume NUL is in byte 1 */
|
|
tst r5, #BYTE1 /* is NUL in byte 2? */
|
|
beq .Lcongruent_last_bytes /* yes, done searching. */
|
|
mov r3, #16 /* assume NUL is in byte 2 */
|
|
tst r5, #BYTE2 /* is NUL in byte 2? */
|
|
#if !defined(STRLCPY)
|
|
beq .Lcongruent_last_bytes /* yes, done searching. */
|
|
mov r3, #24 /* NUL must be in byte 3 */
|
|
#else
|
|
movne r3, #24 /* no, then NUL is in byte 3 */
|
|
#endif
|
|
#endif /* _ARM_ARCH_6 */
|
|
#if defined(STRLCPY)
|
|
.Lcongruent_last_bytes:
|
|
#endif
|
|
#if defined(STRLCPY)
|
|
add r1, r1, r3, lsr #3 /* position to point at NUL + 4 */
|
|
#endif
|
|
b .Llast_bytes /* store the last bytes */
|
|
|
|
|
|
.Lincongruent:
|
|
/*
|
|
* At this point dst is word aligned by src is not. Read bytes
|
|
* from src until it is read aligned.
|
|
*/
|
|
and r3, r1, #3 /* extract misalignment */
|
|
mov r9, r3, lsl #3 /* calculate discard shift */
|
|
rsb r8, r9, #32 /* calculate insertion shift */
|
|
#if defined(STRLCPY)
|
|
add r6, r6, #3 /* compensate for word post-inc */
|
|
#endif
|
|
bic r1, r1, #3 /* word align src */
|
|
ldr r5, [r1], #4 /* load word frm src */
|
|
mov r4, r5, lslo r9 /* discard lo bytes from src */
|
|
tst r4, #BYTE0 /* does byte 0 contain a NUL? */
|
|
#if defined(STRNCPY)
|
|
beq .Lend_of_string /* yes, zero fill rest of string */
|
|
#else
|
|
moveq r3, r9 /* yes, set offset */
|
|
beq .Lincongruent_end_of_string /* yes, deal with the last bytes */
|
|
#endif
|
|
/*
|
|
* To make our test for NULs below do not generate false positives,
|
|
* fill the bytes in the word we don't want to match with all 1s.
|
|
*/
|
|
mvn r3, #0 /* create a mask */
|
|
mov r3, r3, lslo r8 /* zero out bytes being kept */
|
|
orr r5, r5, r3 /* merge src and mask */
|
|
#ifdef _ARM_ARCH_6
|
|
uqadd8 r3, r5, r7 /* NUL detection magic happens */
|
|
mvns r3, r3 /* is the complemented result 0? */
|
|
beq .Lincongruent_mainloop_load /* yes, no NUL encountered! */
|
|
#ifdef __ARMEL__
|
|
rev r3, r3 /* CLZ wants BE input */
|
|
#endif
|
|
clz r3, r3 /* count leading zeros */
|
|
#else
|
|
/*
|
|
* We already tested for byte 0 above so we don't need to it again.
|
|
*/
|
|
mov r3, #24 /* assume NUL is in byte 3 */
|
|
tst r5, #BYTE1 /* did we find a NUL in byte 1? */
|
|
subeq r3, r3, #8 /* yes, decremnt byte position */
|
|
tstne r5, #BYTE2 /* no, did we find a NUL in byte 2? */
|
|
subeq r3, r3, #8 /* yes, decremnt byte position */
|
|
tstne r5, #BYTE3 /* no, did we find a NUL in byte 3? */
|
|
bne .Lincongruent_mainloop_load /* no, no NUL encountered! */
|
|
#endif
|
|
mov r5, r4 /* discard already dealt with bytes */
|
|
.Lincongruent_end_of_string:
|
|
#if defined(STRLCPY)
|
|
add r1, r1, r3, lsr #3 /* then add offset to NUL */
|
|
#endif
|
|
sub r3, r3, r9 /* adjust NUL offset */
|
|
b .Llast_bytes /* NUL encountered! finish up */
|
|
|
|
#if defined(STRLCPY) || defined(STRNCPY)
|
|
.Lincongruent_no_more_room:
|
|
mov r5, r4 /* move data to be stored to r5 */
|
|
b .Lno_more_room /* fill remaining space */
|
|
#endif /* STRLCPY || STRNCPY */
|
|
|
|
/*
|
|
* At this point both dst and src are word aligned and r4 contains
|
|
* partial contents from src.
|
|
*/
|
|
.Lincongruent_mainloop:
|
|
orr r4, r4, r5, lshi r8 /* put new src data into dst word */
|
|
#if defined(STRLCPY) || defined(STRNCPY)
|
|
subs r2, r2, #4 /* subtract 4 from count */
|
|
bmi .Lincongruent_no_more_room /* count < 0? dst will be full */
|
|
#endif
|
|
str r4, [r0], #4 /* store word in dst */
|
|
#if defined(STRLCPY)
|
|
beq .Lno_more_room /* space left is 0? stop copy */
|
|
#endif
|
|
#if defined(STRNCPY)
|
|
beq .Ldst_full_word_aligned /* space left is 0? stop copy */
|
|
#endif
|
|
mov r4, r5, lslo r9 /* move rest of src into dst word */
|
|
.Lincongruent_mainloop_load:
|
|
ldr r5, [r1], #4 /* read src */
|
|
#ifdef _ARM_ARCH_6
|
|
uqadd8 r3, r5, r7 /* magic happens here */
|
|
mvns r3, r3 /* is the complemented result 0? */
|
|
beq .Lincongruent_mainloop /* yes, no NUL encountered! */
|
|
/*
|
|
* fall into this since we encountered a NULL. At this point we have
|
|
* from 1-5 bytes (excluding trailing NUL) to write.
|
|
*/
|
|
#ifdef __ARMEL__
|
|
rev r3, r3 /* CLZ works on BE data */
|
|
#endif
|
|
clz r3, r3 /* count leading zeroes */
|
|
#else
|
|
tst r5, #BYTE0 /* does byte 0 contain a NUL? */
|
|
tstne r5, #BYTE1 /* no, does byte 1 contain a NUL? */
|
|
tstne r5, #BYTE2 /* no, does byte 2 contain a NUL? */
|
|
tstne r5, #BYTE3 /* no, does byte 3 contain a NUL? */
|
|
bne .Lincongruent_mainloop /* no, no NUL encountered! */
|
|
/*
|
|
* fall into this since we encountered a NULL. At this point we have
|
|
* from 1-5 bytes (excluding trailing NUL) to write.
|
|
*/
|
|
mov r3, #0 /* assume a NUL is in byte 0 */
|
|
tst r5, #BYTE0 /* is there a NUL in byte 0? */
|
|
beq 1f /* yes, found a NUL! */
|
|
mov r3, #8 /* assume a NUL is in byte 1 */
|
|
tst r5, #BYTE1 /* is there a NUL in byte 0? */
|
|
beq 1f /* yes, found a NUL! */
|
|
tst r5, #BYTE2 /* is there a NUL in byte 2? */
|
|
moveq r3, #16 /* yes, mark its position */
|
|
movne r3, #24 /* no, it must be in byte 3 */
|
|
1:
|
|
#endif
|
|
orr r4, r4, r5, lshi r8 /* merge new and old src words */
|
|
#if defined(STRLCPY)
|
|
add r1, r1, r3, lsr #3 /* adjust src to point to NUL */
|
|
#endif
|
|
add r3, r3, r8 /* add remainder bytes worth */
|
|
cmp r3, #32 /* do we have at least one word to write? */
|
|
movlt r5, r4 /* no, move source bytes to expected reg */
|
|
blt .Llast_bytes /* no, deal with them */
|
|
#if defined(STRLCPY)
|
|
subs r2, r2, #4 /* subtract 4 from count */
|
|
bpl 1f /* we have space for at least 4 */
|
|
/*
|
|
* Since the space just went minus, we don't have enough room to
|
|
* write all 4 bytes. In fact, the most we can write is 3 so just
|
|
* just lie and say we have 3 bytes to write and discard the rest.
|
|
*/
|
|
add r2, r2, #4 /* add 4 back */
|
|
mov r3, #24 /* say we have 3 bytes */
|
|
mov r5, r4 /* discard the bytes we can't store */
|
|
b .Llast_bytes /* and treat this as our last word */
|
|
1:
|
|
#elif defined(STRNCPY)
|
|
subs r2, r2, #4 /* subtract 4 from count */
|
|
bmi .Lincongruent_no_more_room /* count < 0? dst will be full */
|
|
#endif
|
|
str r4, [r0], #4 /* store dst word */
|
|
#if defined(STRNCPY)
|
|
beq .Ldst_full_word_aligned /* space left is 0? stop copy */
|
|
#endif
|
|
#if defined(STRLCPY)
|
|
bne 1f /* we still have space remaining */
|
|
strb r2, [r0] /* write final NUL */
|
|
b .Lend_of_string /* we are done */
|
|
1:
|
|
#endif
|
|
/*
|
|
* Subtract the 32 bits just written from the number of bits left
|
|
* to write. If 0 bits are left and not doing strncpy, just write
|
|
* the trailing NUL and be done.
|
|
*/
|
|
subs r3, r3, #32 /* we wrote one word */
|
|
#if !defined(STRNCPY)
|
|
bne 1f /* no more data? */
|
|
strb r3, [r0] /* write final NUL */
|
|
b .Lend_of_string /* we are done */
|
|
1:
|
|
#endif
|
|
/*
|
|
* At this point after writing 4 bytes, we have 0 or 1 bytes left to
|
|
* write (excluding the trailing NUL).
|
|
*/
|
|
mov r5, r5, lslo r9 /* get remainder of src */
|
|
|
|
/* fall into .Llast_bytes */
|
|
|
|
#if !defined(STRLCPY)
|
|
.Lcongruent_last_bytes:
|
|
#endif
|
|
.Llast_bytes:
|
|
/*
|
|
* r5 contains the last word and is in host byte order.
|
|
* r3 contains number of bits left to copy (0..31).
|
|
* r1 should point to the NUL + 4.
|
|
*/
|
|
bics ip, r3, #7 /* truncate bits, is result 0? */
|
|
#if !defined(STRNCPY)
|
|
bne 1f /* no, have to write some bytes */
|
|
strb ip, [r0] /* yes, write trailing NUL */
|
|
b .Lend_of_string /* yes, and we are the end */
|
|
1:
|
|
#endif
|
|
#if defined(STRLCPY) || defined(STRNCPY)
|
|
cmp r2, ip, lsr #3 /* is there enough room? */
|
|
movlt ip, r2, lsl #3 /* no, only fill remaining space */
|
|
#endif
|
|
mvn r3, #0 /* create a mask */
|
|
mov r3, r3, lshi ip /* clear leading bytes */
|
|
bic r5, r5, r3 /* clear trailing bytes */
|
|
#if defined(STRNCPY)
|
|
cmp r2, #4 /* room for 4 bytes? */
|
|
movge ip, #32 /* yes, we will write 4 bytes */
|
|
bge 2f /* yes, and go do it */
|
|
mvn r3, #0 /* create a mask (again) */
|
|
mov ip, r2, lsl #3 /* remaining space bytes -> bits */
|
|
mov r3, r3, lshi ip /* clear remaining bytes */
|
|
#elif defined(STRLCPY)
|
|
cmp r2, #3 /* do we have room for 3 bytes & NUL? */
|
|
bge 2f /* yes, just clear out dst */
|
|
mov r3, r3, lshi #8 /* mask out trailing NUL */
|
|
#else
|
|
cmp ip, #24 /* are we writing 3 bytes & a NUL? */
|
|
bge 2f /* yes, just overwrite dst */
|
|
mov r3, r3, lshi #8 /* mask out trailing NUL */
|
|
#endif /* !STRNCPY */
|
|
ldr r4, [r0] /* fetch dst word */
|
|
and r4, r4, r3 /* preserve trailing bytes */
|
|
orr r5, r5, r4 /* merge dst with src */
|
|
2: str r5, [r0], #4 /* store last word */
|
|
#if defined(STRNCPY)
|
|
subs r2, r2, ip, lsr #3 /* subtract bytes cleared from count */
|
|
beq .Ldst_full_word_aligned
|
|
#endif
|
|
b .Lend_of_string
|
|
|
|
#if defined(STRLCPY) || defined(STRNCPY)
|
|
.Lno_more_room:
|
|
#if defined(STRLCPY)
|
|
cmp r2, #-1 /* tried to write 3 bytes? */
|
|
blt 1f /* less, partial word write */
|
|
cmp r2, #0 /* no space left? */
|
|
strbeq r2, [r0] /* write the final NUL */
|
|
bicne r5, r5, #BYTE3 /* clear trailing NUL */
|
|
strne r5, [r0] /* write last word */
|
|
b .Ldst_full_word_aligned /* the dst buffer is full */
|
|
1:
|
|
#endif /* STRLCPY */
|
|
add r2, r2, #4 /* restore remaining space */
|
|
ldr r4, [r0] /* load dst */
|
|
mvn r3, #0 /* create a mask */
|
|
mov r2, r2, lsl #3 /* bytes -> bits */
|
|
mov r3, r3, lshi r2 /* clear leading bytes */
|
|
bic r5, r5, r3 /* clear trailing bytes from src */
|
|
#if defined(STRLCPY)
|
|
mov r3, r3, lshi #8 /* mask out trailing NUL */
|
|
#endif /* STRLCPY */
|
|
and r4, r4, r3 /* preserve trailing bytes in dst */
|
|
orr r4, r4, r5 /* merge src with dst */
|
|
str r4, [r0], #4 /* write last word */
|
|
b .Ldst_full_word_aligned
|
|
#endif /* STRLCPY || STRNCPY */
|
|
|
|
#if defined(STRLCPY)
|
|
/*
|
|
* Destination was filled (and NUL terminated).
|
|
* All that's left is count the number of bytes left in src.
|
|
*/
|
|
.Ldst_full:
|
|
1: tst r1, #3 /* dst word aligned? */
|
|
beq 2f /* yes, so do it word by word */
|
|
ldrb r5, [r1], #1 /* load next byte */
|
|
teq r5, #0 /* is it a NUL? */
|
|
bne 1b /* no, check alignment */
|
|
b .Lend_of_string /* and return */
|
|
2: add r6, r6, #3 /* compensate for post-inc */
|
|
.Ldst_full_word_aligned:
|
|
3: ldr r5, [r1], #4 /* load word from src */
|
|
#ifdef _ARM_ARCH_6
|
|
uqadd8 r5, r5, r7 /* perform NUL magic */
|
|
mvns r5, r5 /* complement all 0s? */
|
|
beq 3b /* yes, no NUL so get next word */
|
|
#else
|
|
tst r5, #BYTE0 /* does byte 0 contain a NUL? */
|
|
tstne r5, #BYTE1 /* no, does byte 1 contain a NUL? */
|
|
tstne r5, #BYTE2 /* no, does byte 2 contain a NUL? */
|
|
tstne r5, #BYTE3 /* no, does byte 3 contain a NUL? */
|
|
bne 3b /* no, no NUL encountered! */
|
|
#endif
|
|
#ifdef _ARM_ARCH_6
|
|
#ifdef __ARMEL__
|
|
rev r5, r5 /* CLZ needs BE data */
|
|
#endif
|
|
clz r5, r5 /* count leading zeros */
|
|
add r1, r1, r5, lsr #3 /* add offset to NUL to src pointer */
|
|
#else
|
|
tst r5, #BYTE0 /* is there a NUL in byte 0? */
|
|
beq 4f /* yes, don't check any further */
|
|
add r1, r1, #1 /* no, advance src pointer by 1 */
|
|
tst r5, #BYTE1 /* is there a NUL in byte 1? */
|
|
beq 4f /* yes, don't check any further */
|
|
add r1, r1, #1 /* no, advance src pointer by 1 */
|
|
tst r5, #BYTE2 /* is there a NUL in byte 2? */
|
|
addne r1, r1, #1 /* no, there must be in byte 3 */
|
|
4:
|
|
#endif /* _ARM_ARCH_6 */
|
|
.Lend_of_string:
|
|
sub r0, r1, r6 /* subtract start from finish */
|
|
pop {r4-r9} /* restore registers */
|
|
RET
|
|
#elif defined(STRNCPY)
|
|
.Lend_of_string:
|
|
teq r2, #0 /* any bytes left to zero? */
|
|
beq 3f /* no, just return. */
|
|
mov r1, #0 /* yes, prepare to zero */
|
|
cmp r2, #16 /* some, but not a lot? */
|
|
ble 1f
|
|
mov r4, lr /* preserve lr */
|
|
bl PLT_SYM(_C_LABEL(memset)) /* yes, and let memset do it */
|
|
mov lr, r4 /* restore lr */
|
|
b 3f /* return */
|
|
1: add ip, r0, r2 /* calculate stopping point */
|
|
2: strb r1, [r0], #1 /* clear a byte */
|
|
cmp r0, ip /* done? */
|
|
blt 2b /* no, clear next byte */
|
|
3: mov r0, r6 /* restore dst pointer */
|
|
pop {r4-r9} /* restore registers */
|
|
RET
|
|
.Ldst_full:
|
|
.Ldst_full_word_aligned:
|
|
/*
|
|
* Destination was filled (but not NUL terminated).
|
|
* All that's left is return the start of dst
|
|
*/
|
|
mov r0, r6 /* restore dst pointer */
|
|
pop {r4-r9} /* restore registers */
|
|
RET
|
|
#else
|
|
.Lend_of_string:
|
|
mov r0, r6 /* restore dst pointer */
|
|
pop {r4-r9} /* restore registers */
|
|
RET
|
|
#endif
|
|
END(FUNCNAME)
|