1/* 2 * CDDL HEADER START 3 * 4 * The contents of this file are subject to the terms of the 5 * Common Development and Distribution License (the "License"). 6 * You may not use this file except in compliance with the License. 7 * 8 * You can obtain a copy of the license at usr/src/OPENSOLARIS.LICENSE 9 * or http://www.opensolaris.org/os/licensing. 10 * See the License for the specific language governing permissions 11 * and limitations under the License. 12 * 13 * When distributing Covered Code, include this CDDL HEADER in each 14 * file and include the License file at usr/src/OPENSOLARIS.LICENSE. 15 * If applicable, add the following below this CDDL HEADER, with the 16 * fields enclosed by brackets "[]" replaced with your own identifying 17 * information: Portions Copyright [yyyy] [name of copyright owner] 18 * 19 * CDDL HEADER END 20 */ 21 22/* 23 * Copyright 2008 Sun Microsystems, Inc. All rights reserved. 24 * Use is subject to license terms. 25 */ 26 27 .ident "%Z%%M% %I% %E% SMI" 28 29 .file "%M%" 30 31/* 32 * memcpy(s1, s2, len) 33 * 34 * Copy s2 to s1, always copy n bytes. 35 * Note: this does not work for overlapped copies, bcopy() does 36 * 37 * Added entry __align_cpy_1 is generally for use of the compilers. 38 * 39 * 40 * Fast assembler language version of the following C-program for memcpy 41 * which represents the `standard' for the C-library. 42 * 43 * void * 44 * memcpy(void *s, const void *s0, size_t n) 45 * { 46 * if (n != 0) { 47 * char *s1 = s; 48 * const char *s2 = s0; 49 * do { 50 * *s1++ = *s2++; 51 * } while (--n != 0); 52 * } 53 * return (s); 54 * } 55 */ 56 57#include <sys/asm_linkage.h> 58 59 ANSI_PRAGMA_WEAK(memcpy,function) 60 61#include "synonyms.h" 62 63 ENTRY(memcpy) 64 ENTRY(__align_cpy_1) 65 mov %o0, %g5 ! save des address for return val 66 cmp %o2, 17 ! for small counts copy bytes 67 bleu,pn %xcc, .dbytecp 68 andcc %o1, 3, %o5 ! is src word aligned 69 bz,pn %icc, .aldst 70 cmp %o5, 2 ! is src half-word aligned 71 be,pt %xcc, .s2algn 72 cmp %o5, 3 ! src is byte aligned 73.s1algn:ldub [%o1], %o3 ! move 1 or 3 bytes to align it 74 inc 1, %o1 75 stb %o3, [%g5] ! move a byte to align src 76 inc 1, %g5 77 bne,pt %icc, .s2algn 78 dec %o2 79 b .ald ! now go align dest 80 andcc %g5, 3, %o5 81 82.s2algn:lduh [%o1], %o3 ! know src is 2 byte alinged 83 inc 2, %o1 84 srl %o3, 8, %o4 85 stb %o4, [%g5] ! have to do bytes, 86 stb %o3, [%g5 + 1] ! don't know dst alingment 87 inc 2, %g5 88 dec 2, %o2 89 90.aldst: andcc %g5, 3, %o5 ! align the destination address 91.ald: bz,pn %icc, .w4cp 92 cmp %o5, 2 93 bz,pn %icc, .w2cp 94 cmp %o5, 3 95.w3cp: lduw [%o1], %o4 96 inc 4, %o1 97 srl %o4, 24, %o5 98 stb %o5, [%g5] 99 bne,pt %icc, .w1cp 100 inc %g5 101 dec 1, %o2 102 andn %o2, 3, %o3 ! o3 is aligned word count 103 dec 4, %o3 ! avoid reading beyond tail of src 104 sub %o1, %g5, %o1 ! o1 gets the difference 105 1061: sll %o4, 8, %g1 ! save residual bytes 107 lduw [%o1+%g5], %o4 108 deccc 4, %o3 109 srl %o4, 24, %o5 ! merge with residual 110 or %o5, %g1, %g1 111 st %g1, [%g5] 112 bnz,pt %xcc, 1b 113 inc 4, %g5 114 sub %o1, 3, %o1 ! used one byte of last word read 115 and %o2, 3, %o2 116 b 7f 117 inc 4, %o2 118 119.w1cp: srl %o4, 8, %o5 120 sth %o5, [%g5] 121 inc 2, %g5 122 dec 3, %o2 123 andn %o2, 3, %o3 ! o3 is aligned word count 124 dec 4, %o3 ! avoid reading beyond tail of src 125 sub %o1, %g5, %o1 ! o1 gets the difference 126 1272: sll %o4, 24, %g1 ! save residual bytes 128 lduw [%o1+%g5], %o4 129 deccc 4, %o3 130 srl %o4, 8, %o5 ! merge with residual 131 or %o5, %g1, %g1 132 st %g1, [%g5] 133 bnz,pt %xcc, 2b 134 inc 4, %g5 135 sub %o1, 1, %o1 ! used three bytes of last word read 136 and %o2, 3, %o2 137 b 7f 138 inc 4, %o2 139 140.w2cp: lduw [%o1], %o4 141 inc 4, %o1 142 srl %o4, 16, %o5 143 sth %o5, [%g5] 144 inc 2, %g5 145 dec 2, %o2 146 andn %o2, 3, %o3 ! o3 is aligned word count 147 dec 4, %o3 ! avoid reading beyond tail of src 148 sub %o1, %g5, %o1 ! o1 gets the difference 149 1503: sll %o4, 16, %g1 ! save residual bytes 151 lduw [%o1+%g5], %o4 152 deccc 4, %o3 153 srl %o4, 16, %o5 ! merge with residual 154 or %o5, %g1, %g1 155 st %g1, [%g5] 156 bnz,pt %xcc, 3b 157 inc 4, %g5 158 sub %o1, 2, %o1 ! used two bytes of last word read 159 and %o2, 3, %o2 160 b 7f 161 inc 4, %o2 162 163.w4cp: andn %o2, 3, %o3 ! o3 is aligned word count 164 sub %o1, %g5, %o1 ! o1 gets the difference 165 1661: lduw [%o1+%g5], %o4 ! read from address 167 deccc 4, %o3 ! decrement count 168 st %o4, [%g5] ! write at destination address 169 bgu,pt %xcc, 1b 170 inc 4, %g5 ! increment to address 171 b 7f 172 and %o2, 3, %o2 ! number of leftover bytes, if any 173 174 ! 175 ! differenced byte copy, works with any alignment 176 ! 177.dbytecp: 178 b 7f 179 sub %o1, %g5, %o1 ! o1 gets the difference 180 1814: stb %o4, [%g5] ! write to address 182 inc %g5 ! inc to address 1837: deccc %o2 ! decrement count 184 bgeu,a,pt %xcc,4b ! loop till done 185 ldub [%o1+%g5], %o4 ! read from address 186 retl 187 nop 188 189 SET_SIZE(memcpy) 190 SET_SIZE(__align_cpy_1) 191