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Diffstat (limited to 'ports/sysdeps/vax/strncmp.s')
| -rw-r--r-- | ports/sysdeps/vax/strncmp.s | 85 |
1 files changed, 85 insertions, 0 deletions
diff --git a/ports/sysdeps/vax/strncmp.s b/ports/sysdeps/vax/strncmp.s new file mode 100644 index 000000000..8d8f5d419 --- /dev/null +++ b/ports/sysdeps/vax/strncmp.s @@ -0,0 +1,85 @@ +/* + * Copyright (c) 1983 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. + * 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 "@(#)strncmp.s 5.6 (Berkeley) 6/1/90" +#endif /* LIBC_SCCS and not lint */ + +/* + * Compare at most n characters of string + * s1 lexicographically to string s2. + * Return: + * 0 s1 == s2 + * > 0 s1 > s2 + * < 0 s2 < s2 + * + * strncmp(s1, s2, n) + * char *s1, *s2; + * int n; + */ +#include "DEFS.h" + +ENTRY(strncmp, 0) + movl 4(ap),r1 # r1 = s1 + movq 8(ap),r3 # r3 = s2; r4 = n +1: + clrl r5 # calculate min bytes to next page boundary + subb3 r1,$255,r5 # r5 = (bytes - 1) to end of page for s1 + subb3 r3,$255,r0 # r0 = (bytes - 1) to end of page for s2 + cmpb r0,r5 # r5 = min(r0, r5); + bgtru 2f + movb r0,r5 +2: + incl r5 # r5 = min bytes to next page boundary + cmpl r4,r5 # r5 = min(n, r5); + bgeq 3f + movl r4,r5 +3: + cmpc3 r5,(r1),(r3) # compare strings + bneq 4f + subl2 r5,r4 # check for end of comparison + beql 5f + subl2 r5,r1 # check if found null yet + locc $0,r5,(r1) + beql 1b # not yet done, continue checking + subl2 r0,r3 + mnegb (r3),r0 # r0 = '\0' - *s2 + cvtbl r0,r0 + ret +4: + subl2 r0,r5 # check for null in matching string + subl2 r5,r1 + locc $0,r5,(r1) + bneq 5f + subb3 (r3),(r1),r0 # r0 = *s1 - *s2 + cvtbl r0,r0 + ret +5: + clrl r0 # both the same to null + ret |