17c478bd9Sstevel@tonic-gate/* 27c478bd9Sstevel@tonic-gate * CDDL HEADER START 37c478bd9Sstevel@tonic-gate * 47c478bd9Sstevel@tonic-gate * The contents of this file are subject to the terms of the 57257d1b4Sraf * Common Development and Distribution License (the "License"). 67257d1b4Sraf * You may not use this file except in compliance with the License. 77c478bd9Sstevel@tonic-gate * 87c478bd9Sstevel@tonic-gate * You can obtain a copy of the license at usr/src/OPENSOLARIS.LICENSE 97c478bd9Sstevel@tonic-gate * or http://www.opensolaris.org/os/licensing. 107c478bd9Sstevel@tonic-gate * See the License for the specific language governing permissions 117c478bd9Sstevel@tonic-gate * and limitations under the License. 127c478bd9Sstevel@tonic-gate * 137c478bd9Sstevel@tonic-gate * When distributing Covered Code, include this CDDL HEADER in each 147c478bd9Sstevel@tonic-gate * file and include the License file at usr/src/OPENSOLARIS.LICENSE. 157c478bd9Sstevel@tonic-gate * If applicable, add the following below this CDDL HEADER, with the 167c478bd9Sstevel@tonic-gate * fields enclosed by brackets "[]" replaced with your own identifying 177c478bd9Sstevel@tonic-gate * information: Portions Copyright [yyyy] [name of copyright owner] 187c478bd9Sstevel@tonic-gate * 197c478bd9Sstevel@tonic-gate * CDDL HEADER END 207c478bd9Sstevel@tonic-gate */ 217257d1b4Sraf 227c478bd9Sstevel@tonic-gate/* 237257d1b4Sraf * Copyright 2008 Sun Microsystems, Inc. All rights reserved. 247257d1b4Sraf * Use is subject to license terms. 257c478bd9Sstevel@tonic-gate */ 267c478bd9Sstevel@tonic-gate 27*9a70fc3bSMark J. Nelson .file "strncmp.s" 287c478bd9Sstevel@tonic-gate 297c478bd9Sstevel@tonic-gate/* 307c478bd9Sstevel@tonic-gate * strncmp(s1, s2, n) 317c478bd9Sstevel@tonic-gate * 327c478bd9Sstevel@tonic-gate * Compare strings (at most n bytes): s1>s2: >0 s1==s2: 0 s1<s2: <0 337c478bd9Sstevel@tonic-gate * 347c478bd9Sstevel@tonic-gate * Fast assembler language version of the following C-program for strncmp 357c478bd9Sstevel@tonic-gate * which represents the `standard' for the C-library. 367c478bd9Sstevel@tonic-gate * 377c478bd9Sstevel@tonic-gate * int 387c478bd9Sstevel@tonic-gate * strncmp(const char *s1, const char *s2, size_t n) 397c478bd9Sstevel@tonic-gate * { 407c478bd9Sstevel@tonic-gate * n++; 417c478bd9Sstevel@tonic-gate * if (s1 == s2) 427c478bd9Sstevel@tonic-gate * return (0); 437c478bd9Sstevel@tonic-gate * while (--n != 0 && *s1 == *s2++) 447c478bd9Sstevel@tonic-gate * if (*s1++ == '\0') 457c478bd9Sstevel@tonic-gate * return (0); 467c478bd9Sstevel@tonic-gate * return ((n == 0) ? 0 : (*s1 - s2[-1])); 477c478bd9Sstevel@tonic-gate * } 487c478bd9Sstevel@tonic-gate */ 497c478bd9Sstevel@tonic-gate 507c478bd9Sstevel@tonic-gate#include <sys/asm_linkage.h> 517c478bd9Sstevel@tonic-gate 527c478bd9Sstevel@tonic-gate ENTRY(strncmp) 537c478bd9Sstevel@tonic-gate save %sp, -SA(WINDOWSIZE), %sp 547c478bd9Sstevel@tonic-gate cmp %i2, 8 557c478bd9Sstevel@tonic-gate blu,a .cmp_bytes ! for small counts go do bytes 567c478bd9Sstevel@tonic-gate sub %i0, %i1, %i0 ! delay slot, get diff from s1 - s2 577c478bd9Sstevel@tonic-gate andcc %i0, 3, %g0 ! is s1 aligned 587c478bd9Sstevel@tonic-gate1: bz .iss2 ! if so go check s2 597c478bd9Sstevel@tonic-gate andcc %i1, 3, %i3 ! is s2 aligned 607c478bd9Sstevel@tonic-gate 617c478bd9Sstevel@tonic-gate deccc %i2 ! --n >= 0 ? 627c478bd9Sstevel@tonic-gate bcs .doneq 637c478bd9Sstevel@tonic-gate nop ! delay slot 647c478bd9Sstevel@tonic-gate 657c478bd9Sstevel@tonic-gate ldub [%i0], %i4 ! else cmp one byte 667c478bd9Sstevel@tonic-gate ldub [%i1], %i5 677c478bd9Sstevel@tonic-gate inc %i0 687c478bd9Sstevel@tonic-gate cmp %i4, %i5 697c478bd9Sstevel@tonic-gate bne .noteqb 707c478bd9Sstevel@tonic-gate inc %i1 717c478bd9Sstevel@tonic-gate tst %i4 ! terminating zero 727c478bd9Sstevel@tonic-gate bnz 1b 737c478bd9Sstevel@tonic-gate andcc %i0, 3, %g0 747c478bd9Sstevel@tonic-gate b,a .doneq 757c478bd9Sstevel@tonic-gate 767c478bd9Sstevel@tonic-gate.iss2: 777c478bd9Sstevel@tonic-gate set 0x7efefeff, %l6 787c478bd9Sstevel@tonic-gate set 0x81010100, %l7 797c478bd9Sstevel@tonic-gate sethi %hi(0xff000000), %l0 ! masks to test for terminating null 807c478bd9Sstevel@tonic-gate sethi %hi(0x00ff0000), %l1 817c478bd9Sstevel@tonic-gate srl %l1, 8, %l2 ! generate 0x0000ff00 mask 827c478bd9Sstevel@tonic-gate 837c478bd9Sstevel@tonic-gate bz .w4cmp ! if s2 word aligned, compare words 847c478bd9Sstevel@tonic-gate cmp %i3, 2 ! check if s2 half aligned 857c478bd9Sstevel@tonic-gate be .w2cmp 867c478bd9Sstevel@tonic-gate cmp %i3, 1 ! check if aligned to 1 or 3 bytes 877c478bd9Sstevel@tonic-gate.w3cmp: ldub [%i1], %i5 887c478bd9Sstevel@tonic-gate inc 1, %i1 897c478bd9Sstevel@tonic-gate be .w1cmp 907c478bd9Sstevel@tonic-gate sll %i5, 24, %i5 917c478bd9Sstevel@tonic-gate sub %i0, %i1, %i0 927c478bd9Sstevel@tonic-gate2: 937c478bd9Sstevel@tonic-gate deccc 4, %i2 ! n >= 4 ? 947c478bd9Sstevel@tonic-gate bgeu,a 3f 957c478bd9Sstevel@tonic-gate ld [%i1], %i3 ! delay slot 967c478bd9Sstevel@tonic-gate dec %i1 ! reset s2 977c478bd9Sstevel@tonic-gate inc %i0 ! reset s1 diff 987c478bd9Sstevel@tonic-gate b .cmp_bytes ! do a byte at a time if n < 4 997c478bd9Sstevel@tonic-gate inc 4, %i2 1007c478bd9Sstevel@tonic-gate3: 1017c478bd9Sstevel@tonic-gate ld [%i0 + %i1], %i4 1027c478bd9Sstevel@tonic-gate inc 4, %i1 1037c478bd9Sstevel@tonic-gate srl %i3, 8, %l4 ! merge with the other half 1047c478bd9Sstevel@tonic-gate or %l4, %i5, %i5 1057c478bd9Sstevel@tonic-gate cmp %i4, %i5 1067c478bd9Sstevel@tonic-gate be 1f 1077c478bd9Sstevel@tonic-gate 1087c478bd9Sstevel@tonic-gate add %i4, %l6, %l3 1097c478bd9Sstevel@tonic-gate b,a .noteq 1107c478bd9Sstevel@tonic-gate1: xor %l3, %i4, %l3 1117c478bd9Sstevel@tonic-gate and %l3, %l7, %l3 1127c478bd9Sstevel@tonic-gate cmp %l3, %l7 1137c478bd9Sstevel@tonic-gate be,a 2b 1147c478bd9Sstevel@tonic-gate sll %i3, 24, %i5 1157c478bd9Sstevel@tonic-gate 1167c478bd9Sstevel@tonic-gate ! 1177c478bd9Sstevel@tonic-gate ! For 7-bit characters, we know one of the bytes is zero, but for 1187c478bd9Sstevel@tonic-gate ! 8-bit characters, the zero detection algorithm gives some false 1197c478bd9Sstevel@tonic-gate ! triggers ... check every byte individually. 1207c478bd9Sstevel@tonic-gate ! 1217c478bd9Sstevel@tonic-gate andcc %i4, %l0, %g0 ! check if first byte was zero 1227c478bd9Sstevel@tonic-gate bnz 1f 1237c478bd9Sstevel@tonic-gate andcc %i4, %l1, %g0 ! check if second byte was zero 1247c478bd9Sstevel@tonic-gate b,a .doneq 1257c478bd9Sstevel@tonic-gate1: bnz 1f 1267c478bd9Sstevel@tonic-gate andcc %i4, %l2, %g0 ! check if third byte was zero 1277c478bd9Sstevel@tonic-gate b,a .doneq 1287c478bd9Sstevel@tonic-gate1: bnz 1f 1297c478bd9Sstevel@tonic-gate andcc %i4, 0xff, %g0 ! check if last byte is zero 1307c478bd9Sstevel@tonic-gate b,a .doneq 1317c478bd9Sstevel@tonic-gate1: bnz 2b 1327c478bd9Sstevel@tonic-gate sll %i3, 24, %i5 1337c478bd9Sstevel@tonic-gate b,a .doneq 1347c478bd9Sstevel@tonic-gate 1357c478bd9Sstevel@tonic-gate.w1cmp: clr %l4 1367c478bd9Sstevel@tonic-gate lduh [%i1], %l4 1377c478bd9Sstevel@tonic-gate inc 2, %i1 1387c478bd9Sstevel@tonic-gate sll %l4, 8, %l4 1397c478bd9Sstevel@tonic-gate or %i5, %l4, %i5 1407c478bd9Sstevel@tonic-gate 1417c478bd9Sstevel@tonic-gate sub %i0, %i1, %i0 1427c478bd9Sstevel@tonic-gate3: 1437c478bd9Sstevel@tonic-gate deccc 4, %i2 ! n >= 4 ? 1447c478bd9Sstevel@tonic-gate bgeu,a 4f 1457c478bd9Sstevel@tonic-gate ld [%i1], %i3 ! delay slot 1467c478bd9Sstevel@tonic-gate dec 3, %i1 ! reset s2 1477c478bd9Sstevel@tonic-gate inc 3, %i0 ! reset s1 diff 1487c478bd9Sstevel@tonic-gate b .cmp_bytes ! do a byte at a time if n < 4 1497c478bd9Sstevel@tonic-gate inc 4, %i2 1507c478bd9Sstevel@tonic-gate4: 1517c478bd9Sstevel@tonic-gate ld [%i0 + %i1], %i4 1527c478bd9Sstevel@tonic-gate inc 4, %i1 1537c478bd9Sstevel@tonic-gate srl %i3, 24, %l4 ! merge with the other half 1547c478bd9Sstevel@tonic-gate or %l4, %i5, %i5 1557c478bd9Sstevel@tonic-gate cmp %i4, %i5 1567c478bd9Sstevel@tonic-gate be 1f 1577c478bd9Sstevel@tonic-gate 1587c478bd9Sstevel@tonic-gate add %i4, %l6, %l3 1597c478bd9Sstevel@tonic-gate b,a .noteq 1607c478bd9Sstevel@tonic-gate1: xor %l3, %i4, %l3 1617c478bd9Sstevel@tonic-gate and %l3, %l7, %l3 1627c478bd9Sstevel@tonic-gate cmp %l3, %l7 1637c478bd9Sstevel@tonic-gate be,a 3b 1647c478bd9Sstevel@tonic-gate sll %i3, 8, %i5 1657c478bd9Sstevel@tonic-gate 1667c478bd9Sstevel@tonic-gate andcc %i4, %l0, %g0 ! check if first byte was zero 1677c478bd9Sstevel@tonic-gate bnz 1f 1687c478bd9Sstevel@tonic-gate andcc %i4, %l1, %g0 ! check if second byte was zero 1697c478bd9Sstevel@tonic-gate b,a .doneq 1707c478bd9Sstevel@tonic-gate1: bnz 1f 1717c478bd9Sstevel@tonic-gate andcc %i4, %l2, %g0 ! check if third byte was zero 1727c478bd9Sstevel@tonic-gate b,a .doneq 1737c478bd9Sstevel@tonic-gate1: bnz 1f 1747c478bd9Sstevel@tonic-gate andcc %i4, 0xff, %g0 ! check if last byte is zero 1757c478bd9Sstevel@tonic-gate b,a .doneq 1767c478bd9Sstevel@tonic-gate1: bnz 3b 1777c478bd9Sstevel@tonic-gate sll %i3, 8, %i5 1787c478bd9Sstevel@tonic-gate b,a .doneq 1797c478bd9Sstevel@tonic-gate 1807c478bd9Sstevel@tonic-gate.w2cmp: 1817c478bd9Sstevel@tonic-gate lduh [%i1], %i5 ! read a halfword to align s2 1827c478bd9Sstevel@tonic-gate inc 2, %i1 1837c478bd9Sstevel@tonic-gate sll %i5, 16, %i5 1847c478bd9Sstevel@tonic-gate 1857c478bd9Sstevel@tonic-gate sub %i0, %i1, %i0 1867c478bd9Sstevel@tonic-gate4: 1877c478bd9Sstevel@tonic-gate deccc 4, %i2 ! n >= 4 ? 1887c478bd9Sstevel@tonic-gate bgeu,a 5f 1897c478bd9Sstevel@tonic-gate ld [%i1], %i3 ! delay slot 1907c478bd9Sstevel@tonic-gate dec 2, %i1 ! reset s2 1917c478bd9Sstevel@tonic-gate inc 2, %i0 ! reset s1 diff 1927c478bd9Sstevel@tonic-gate b .cmp_bytes ! do a byte at a time if n < 4 1937c478bd9Sstevel@tonic-gate inc 4, %i2 ! delay slot 1947c478bd9Sstevel@tonic-gate5: 1957c478bd9Sstevel@tonic-gate ld [%i1 + %i0], %i4 ! read a word from s2 1967c478bd9Sstevel@tonic-gate inc 4, %i1 1977c478bd9Sstevel@tonic-gate srl %i3, 16, %l4 ! merge with the other half 1987c478bd9Sstevel@tonic-gate or %l4, %i5, %i5 1997c478bd9Sstevel@tonic-gate cmp %i4, %i5 2007c478bd9Sstevel@tonic-gate be 1f 2017c478bd9Sstevel@tonic-gate 2027c478bd9Sstevel@tonic-gate add %i4, %l6, %l3 2037c478bd9Sstevel@tonic-gate b,a .noteq 2047c478bd9Sstevel@tonic-gate1: xor %l3, %i4, %l3 ! are any bytes 0? 2057c478bd9Sstevel@tonic-gate and %l3, %l7, %l3 2067c478bd9Sstevel@tonic-gate cmp %l3, %l7 2077c478bd9Sstevel@tonic-gate be,a 4b 2087c478bd9Sstevel@tonic-gate sll %i3, 16, %i5 2097c478bd9Sstevel@tonic-gate 2107c478bd9Sstevel@tonic-gate andcc %i4, %l0, %g0 ! check if first byte was zero 2117c478bd9Sstevel@tonic-gate bnz 1f 2127c478bd9Sstevel@tonic-gate andcc %i4, %l1, %g0 ! check if second byte was zero 2137c478bd9Sstevel@tonic-gate b,a .doneq 2147c478bd9Sstevel@tonic-gate1: bnz 1f 2157c478bd9Sstevel@tonic-gate andcc %i4, %l2, %g0 ! check if third byte was zero 2167c478bd9Sstevel@tonic-gate b,a .doneq 2177c478bd9Sstevel@tonic-gate1: bnz 1f 2187c478bd9Sstevel@tonic-gate andcc %i4, 0xff, %g0 ! check if last byte is zero 2197c478bd9Sstevel@tonic-gate b,a .doneq 2207c478bd9Sstevel@tonic-gate1: bnz 4b 2217c478bd9Sstevel@tonic-gate sll %i3, 16, %i5 2227c478bd9Sstevel@tonic-gate b,a .doneq 2237c478bd9Sstevel@tonic-gate 2247c478bd9Sstevel@tonic-gate.w4cmp: sub %i0, %i1, %i0 2257c478bd9Sstevel@tonic-gate ld [%i1], %i5 ! read a word from s1 2267c478bd9Sstevel@tonic-gate5: cmp %i2,0 2277c478bd9Sstevel@tonic-gate be,a .doneq 2287c478bd9Sstevel@tonic-gate nop 2297c478bd9Sstevel@tonic-gate ld [%i1], %i5 ! read a word from s1 2307c478bd9Sstevel@tonic-gate deccc 4, %i2 ! n >= 4 ? 2317c478bd9Sstevel@tonic-gate bcs,a .cmp_bytes ! do a byte at a time if n < 4 2327c478bd9Sstevel@tonic-gate inc 4, %i2 2337c478bd9Sstevel@tonic-gate 2347c478bd9Sstevel@tonic-gate ld [%i1 + %i0], %i4 ! read a word from s2 2357c478bd9Sstevel@tonic-gate cmp %i4, %i5 2367c478bd9Sstevel@tonic-gate inc 4, %i1 2377c478bd9Sstevel@tonic-gate be 1f 2387c478bd9Sstevel@tonic-gate 2397c478bd9Sstevel@tonic-gate add %i4, %l6, %l3 2407c478bd9Sstevel@tonic-gate b,a .noteq 2417c478bd9Sstevel@tonic-gate1: xor %l3, %i4, %l3 2427c478bd9Sstevel@tonic-gate and %l3, %l7, %l3 2437c478bd9Sstevel@tonic-gate cmp %l3, %l7 2447c478bd9Sstevel@tonic-gate be,a 5b 2457c478bd9Sstevel@tonic-gate nop 2467c478bd9Sstevel@tonic-gate 2477c478bd9Sstevel@tonic-gate andcc %i4, %l0, %g0 ! check if first byte was zero 2487c478bd9Sstevel@tonic-gate bnz 1f 2497c478bd9Sstevel@tonic-gate andcc %i4, %l1, %g0 ! check if second byte was zero 2507c478bd9Sstevel@tonic-gate b,a .doneq 2517c478bd9Sstevel@tonic-gate1: bnz 1f 2527c478bd9Sstevel@tonic-gate andcc %i4, %l2, %g0 ! check if third byte was zero 2537c478bd9Sstevel@tonic-gate b,a .doneq 2547c478bd9Sstevel@tonic-gate1: bnz 1f 2557c478bd9Sstevel@tonic-gate andcc %i4, 0xff, %g0 ! check if last byte is zero 2567c478bd9Sstevel@tonic-gate b,a .doneq 2577c478bd9Sstevel@tonic-gate1: bnz,a 5b 2587c478bd9Sstevel@tonic-gate ld [%i1], %i5 2597c478bd9Sstevel@tonic-gate.doneq: ret 2607c478bd9Sstevel@tonic-gate restore %g0, %g0, %o0 ! equal return zero 2617c478bd9Sstevel@tonic-gate 2627c478bd9Sstevel@tonic-gate.noteq: srl %i4, 24, %l4 2637c478bd9Sstevel@tonic-gate srl %i5, 24, %l5 2647c478bd9Sstevel@tonic-gate subcc %l4, %l5, %i0 2657c478bd9Sstevel@tonic-gate bne 6f 2667c478bd9Sstevel@tonic-gate andcc %l4, 0xff, %g0 2677c478bd9Sstevel@tonic-gate bz .doneq 2687c478bd9Sstevel@tonic-gate sll %i4, 8, %l4 2697c478bd9Sstevel@tonic-gate sll %i5, 8, %l5 2707c478bd9Sstevel@tonic-gate srl %l4, 24, %l4 2717c478bd9Sstevel@tonic-gate srl %l5, 24, %l5 2727c478bd9Sstevel@tonic-gate subcc %l4, %l5, %i0 2737c478bd9Sstevel@tonic-gate bne 6f 2747c478bd9Sstevel@tonic-gate andcc %l4, 0xff, %g0 2757c478bd9Sstevel@tonic-gate bz .doneq 2767c478bd9Sstevel@tonic-gate sll %i4, 16, %l4 2777c478bd9Sstevel@tonic-gate sll %i5, 16, %l5 2787c478bd9Sstevel@tonic-gate srl %l4, 24, %l4 2797c478bd9Sstevel@tonic-gate srl %l5, 24, %l5 2807c478bd9Sstevel@tonic-gate subcc %l4, %l5, %i0 2817c478bd9Sstevel@tonic-gate bne 6f 2827c478bd9Sstevel@tonic-gate andcc %l4, 0xff, %g0 2837c478bd9Sstevel@tonic-gate bz .doneq 2847c478bd9Sstevel@tonic-gate nop 2857c478bd9Sstevel@tonic-gate.noteqb: 2867c478bd9Sstevel@tonic-gate and %i4, 0xff, %l4 2877c478bd9Sstevel@tonic-gate and %i5, 0xff, %l5 2887c478bd9Sstevel@tonic-gate subcc %l4, %l5, %i0 2897c478bd9Sstevel@tonic-gate6: ret 2907c478bd9Sstevel@tonic-gate restore %i0, %g0, %o0 2917c478bd9Sstevel@tonic-gate 2927c478bd9Sstevel@tonic-gate ! Do a byte by byte comparison, disregarding alignments 2937c478bd9Sstevel@tonic-gate.cmp_bytes: 2947c478bd9Sstevel@tonic-gate deccc %i2 ! --n >= 0 ? 2957c478bd9Sstevel@tonic-gate1: 2967c478bd9Sstevel@tonic-gate bcs .doneq 2977c478bd9Sstevel@tonic-gate nop ! delay slot 2987c478bd9Sstevel@tonic-gate ldub [%i1 + %i0], %i4 ! read a word from s1 2997c478bd9Sstevel@tonic-gate ldub [%i1], %i5 ! read a word from s2 3007c478bd9Sstevel@tonic-gate 3017c478bd9Sstevel@tonic-gate inc %i1 3027c478bd9Sstevel@tonic-gate cmp %i4, %i5 3037c478bd9Sstevel@tonic-gate bne .noteqb 3047c478bd9Sstevel@tonic-gate tst %i4 ! terminating zero 3057c478bd9Sstevel@tonic-gate bnz 1b 3067c478bd9Sstevel@tonic-gate deccc %i2 ! --n >= 0 3077c478bd9Sstevel@tonic-gate b,a .doneq 3087c478bd9Sstevel@tonic-gate 3097c478bd9Sstevel@tonic-gate SET_SIZE(strncmp) 310