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Diffstat (limited to 'sysdeps/vax/memchr.s')
| -rw-r--r-- | sysdeps/vax/memchr.s | 73 |
1 files changed, 73 insertions, 0 deletions
diff --git a/sysdeps/vax/memchr.s b/sysdeps/vax/memchr.s new file mode 100644 index 0000000000..c7793fb5f8 --- /dev/null +++ b/sysdeps/vax/memchr.s @@ -0,0 +1,73 @@ +/*- + * Copyright (c) 1990 The Regents of the University of California. + * 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. All advertising materials mentioning features or use of this software + * must display the following acknowledgement: + * This product includes software developed by the University of + * California, Berkeley and its contributors. + * 4. Neither the name of the University nor the names of its contributors + * may be used to endorse or promote products derived from this software + * without specific prior written permission. + * + * THIS SOFTWARE IS PROVIDED BY THE REGENTS 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 REGENTS 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. + */ + +#if defined(LIBC_SCCS) && !defined(lint) + .asciz "@(#)memchr.s 5.1 (Berkeley) 5/29/90" +#endif /* LIBC_SCCS and not lint */ + +/* + * Find the first occurence of c in the memory at cp (length n). + * Return pointer to match or null pointer. + * + * This code optimises the usual case (0 < n < 65535). + * + * void * + * memchr(cp, c, n) + * char *cp, c; + * size_t n; + */ + +#include "DEFS.h" + +ENTRY(memchr, 0) + movq 4(ap),r1 # r1 = cp; r2 = c + movl 12(ap),r0 # r0 = n + movzwl $65535,r4 # handy constant +0: + cmpl r0,r4 # check for annoying locc limit + bgtru 3f + + /* n <= 65535 */ + locc r2,r0,(r1) # search n bytes for c + beql 2f # done if not found (r0 already 0) +1: /* found character c at (r1) */ + movl r1,r0 +2: + ret + +3: /* n > 65535 */ + locc r2,r4,(r1) # search 65535 bytes for c + beql 1b # done if found + decw r0 # from 0 to 65535 + subl2 r0,r4 # adjust n + brb 0b # and loop |