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[src/trunk]: src/common/lib/libc/arch/arm/string Depending on _STANDALONE inc...
details: https://anonhg.NetBSD.org/src/rev/17fc83fb0733
branches: trunk
changeset: 783780:17fc83fb0733
user: matt <matt%NetBSD.org@localhost>
date: Tue Jan 08 13:21:05 2013 +0000
description:
Depending on _STANDALONE include the "naive" version or the normal arm version.
diffstat:
common/lib/libc/arch/arm/string/strcpy.S | 528 +------------------------------
common/lib/libc/arch/arm/string/strlen.S | 122 +------
2 files changed, 8 insertions(+), 642 deletions(-)
diffs (truncated from 664 to 300 lines):
diff -r 4ac207a24a69 -r 17fc83fb0733 common/lib/libc/arch/arm/string/strcpy.S
--- a/common/lib/libc/arch/arm/string/strcpy.S Tue Jan 08 13:17:45 2013 +0000
+++ b/common/lib/libc/arch/arm/string/strcpy.S Tue Jan 08 13:21:05 2013 +0000
@@ -1,527 +1,7 @@
-/*-
- * 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.S,v 1.2 2013/01/02 15:38:03 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 */
- streqb 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 */
- streqb 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 byte being kept */
- orr r3, r3, r5 /* merge src and mask */
-#ifdef _ARM_ARCH_6
- uqadd8 r3, r3, 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 */
+/* $NetBSD: strcpy.S,v 1.3 2013/01/08 13:21:05 matt Exp $ */
- /*
- * 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 */
+#ifdef _STANDALONE
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