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Diffstat (limited to 'newlib/libc/machine/arm/strlen.c')
| -rw-r--r-- | newlib/libc/machine/arm/strlen.c | 180 |
1 files changed, 0 insertions, 180 deletions
diff --git a/newlib/libc/machine/arm/strlen.c b/newlib/libc/machine/arm/strlen.c deleted file mode 100644 index f31f72170..000000000 --- a/newlib/libc/machine/arm/strlen.c +++ /dev/null @@ -1,180 +0,0 @@ -/* - * Copyright (c) 2008 ARM Ltd - * All rights reserved. - * - * 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. - * 3. The name of the company may not be used to endorse or promote - * products derived from this software without specific prior written - * permission. - * - * THIS SOFTWARE IS PROVIDED BY ARM LTD ``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 ARM LTD 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 "arm_asm.h" -#include <_ansi.h> -#include <string.h> -#include <limits.h> - -#if defined (__OPTIMIZE_SIZE__) || defined (PREFER_SIZE_OVER_SPEED) || \ - (defined (__thumb__) && !defined (__thumb2__)) - -size_t -strlen (const char* str) -{ - int scratch; -#if defined (__thumb__) && !defined (__thumb2__) - size_t len; - asm ("mov %0, #0\n" - "1:\n\t" - "ldrb %1, [%2, %0]\n\t" - "add %0, %0, #1\n\t" - "cmp %1, #0\n\t" - "bne 1b" - : "=&r" (len), "=&r" (scratch) : "r" (str) : "memory", "cc"); - return len - 1; -#else - const char* end; - asm ("1:\n\t" - "ldrb %1, [%0], #1\n\t" - "cmp %1, #0\n\t" - "bne 1b" - : "=&r" (end), "=&r" (scratch) : "0" (str) : "memory", "cc"); - return end - str - 1; -#endif -} -#else - -size_t __attribute__((naked)) -strlen (const char* str) -{ - asm ("len .req r0\n\t" - "data .req r3\n\t" - "addr .req r1\n\t" - - "optpld r0\n\t" - /* Word-align address */ - "bic addr, r0, #3\n\t" - /* Get adjustment for start ... */ - "ands len, r0, #3\n\t" - "neg len, len\n\t" - /* First word of data */ - "ldr data, [addr], #4\n\t" - /* Ensure bytes preceeding start ... */ - "add ip, len, #4\n\t" - "mov ip, ip, asl #3\n\t" - "mvn r2, #0\n\t" - /* ... are masked out */ -#ifdef __thumb__ - "itt ne\n\t" -# ifdef __ARMEB__ - "lslne r2, ip\n\t" -# else - "lsrne r2, ip\n\t" -# endif - "orrne data, data, r2\n\t" -#else - "it ne\n\t" -# ifdef __ARMEB__ - "orrne data, data, r2, lsl ip\n\t" -# else - "orrne data, data, r2, lsr ip\n\t" -# endif -#endif - /* Magic const 0x01010101 */ -#ifdef _ISA_ARM_7 - "movw ip, #0x101\n\t" -#else - "mov ip, #0x1\n\t" - "orr ip, ip, ip, lsl #8\n\t" -#endif - "orr ip, ip, ip, lsl #16\n" - - /* This is the main loop. We subtract one from each byte in - the word: the sign bit changes iff the byte was zero or - 0x80 -- we eliminate the latter case by anding the result - with the 1-s complement of the data. */ - "1:\n\t" - /* test (data - 0x01010101) */ - "sub r2, data, ip\n\t" - /* ... & ~data */ - "bic r2, r2, data\n\t" - /* ... & 0x80808080 == 0? */ - "ands r2, r2, ip, lsl #7\n\t" -#ifdef _ISA_ARM_7 - /* yes, get more data... */ - "itt eq\n\t" - "ldreq data, [addr], #4\n\t" - /* and 4 more bytes */ - "addeq len, len, #4\n\t" - /* If we have PLD, then unroll the loop a bit. */ - "optpld addr, #8\n\t" - /* test (data - 0x01010101) */ - "ittt eq\n\t" - "subeq r2, data, ip\n\t" - /* ... & ~data */ - "biceq r2, r2, data\n\t" - /* ... & 0x80808080 == 0? */ - "andeqs r2, r2, ip, lsl #7\n\t" -#endif - "itt eq\n\t" - /* yes, get more data... */ - "ldreq data, [addr], #4\n\t" - /* and 4 more bytes */ - "addeq len, len, #4\n\t" - "beq 1b\n\t" -#ifdef __ARMEB__ - "tst data, #0xff000000\n\t" - "itttt ne\n\t" - "addne len, len, #1\n\t" - "tstne data, #0xff0000\n\t" - "addne len, len, #1\n\t" - "tstne data, #0xff00\n\t" - "it ne\n\t" - "addne len, len, #1\n\t" -#else -# ifdef _ISA_ARM_5 - /* R2 is the residual sign bits from the above test. All we - need to do now is establish the position of the first zero - byte... */ - /* Little-endian is harder, we need the number of trailing - zeros / 8 */ -# ifdef _ISA_ARM_7 - "rbit r2, r2\n\t" - "clz r2, r2\n\t" -# else - "rsb r1, r2, #0\n\t" - "and r2, r2, r1\n\t" - "clz r2, r2\n\t" - "rsb r2, r2, #31\n\t" -# endif - "add len, len, r2, lsr #3\n\t" -# else /* No CLZ instruction */ - "tst data, #0xff\n\t" - "itttt ne\n\t" - "addne len, len, #1\n\t" - "tstne data, #0xff00\n\t" - "addne len, len, #1\n\t" - "tstne data, #0xff0000\n\t" - "it ne\n\t" - "addne len, len, #1\n\t" -# endif -#endif - "RETURN"); -} -#endif |