| yuezonghe | 824eb0c | 2024-06-27 02:32:26 -0700 | [diff] [blame] | 1 | /* memchr (str, ch, n) -- Return pointer to first occurrence of CH in STR less |
| 2 | than N. |
| 3 | For SPARC v9. |
| 4 | Copyright (C) 1998, 1999, 2000, 2003 Free Software Foundation, Inc. |
| 5 | This file is part of the GNU C Library. |
| 6 | Contributed by Jan Vondrak <jvon4518@ss1000.ms.mff.cuni.cz> and |
| 7 | Jakub Jelinek <jj@ultra.linux.cz>. |
| 8 | This version is developed using the same algorithm as the fast C |
| 9 | version which carries the following introduction: |
| 10 | Based on strlen implementation by Torbjorn Granlund (tege@sics.se), |
| 11 | with help from Dan Sahlin (dan@sics.se) and |
| 12 | commentary by Jim Blandy (jimb@ai.mit.edu); |
| 13 | adaptation to memchr suggested by Dick Karpinski (dick@cca.ucsf.edu), |
| 14 | and implemented by Roland McGrath (roland@ai.mit.edu). |
| 15 | |
| 16 | The GNU C Library is free software; you can redistribute it and/or |
| 17 | modify it under the terms of the GNU Lesser General Public |
| 18 | License as published by the Free Software Foundation; either |
| 19 | version 2.1 of the License, or (at your option) any later version. |
| 20 | |
| 21 | The GNU C Library is distributed in the hope that it will be useful, |
| 22 | but WITHOUT ANY WARRANTY; without even the implied warranty of |
| 23 | MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU |
| 24 | Lesser General Public License for more details. |
| 25 | |
| 26 | You should have received a copy of the GNU Lesser General Public |
| 27 | License along with the GNU C Library; if not, write to the Free |
| 28 | Software Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA |
| 29 | 02111-1307 USA. */ |
| 30 | |
| 31 | #include <asm/asi.h> |
| 32 | #ifndef XCC |
| 33 | #define XCC xcc |
| 34 | #define USE_BPR |
| 35 | .register %g2, #scratch |
| 36 | .register %g3, #scratch |
| 37 | #endif |
| 38 | |
| 39 | /* Normally, this uses |
| 40 | ((xword - 0x0101010101010101) & 0x8080808080808080) test |
| 41 | to find out if any byte in xword could be zero. This is fast, but |
| 42 | also gives false alarm for any byte in range 0x81-0xff. It does |
| 43 | not matter for correctness, as if this test tells us there could |
| 44 | be some zero byte, we check it byte by byte, but if bytes with |
| 45 | high bits set are common in the strings, then this will give poor |
| 46 | performance. You can #define EIGHTBIT_NOT_RARE and the algorithm |
| 47 | will use one tick slower, but more precise test |
| 48 | ((xword - 0x0101010101010101) & (~xword) & 0x8080808080808080), |
| 49 | which does not give any false alarms (but if some bits are set, |
| 50 | one cannot assume from it which bytes are zero and which are not). |
| 51 | It is yet to be measured, what is the correct default for glibc |
| 52 | in these days for an average user. |
| 53 | */ |
| 54 | |
| 55 | .text |
| 56 | .align 32 |
| 57 | ENTRY(memchr) |
| 58 | and %o1, 0xff, %o1 /* IEU0 Group */ |
| 59 | #ifdef USE_BPR |
| 60 | brz,pn %o2, 12f /* CTI+IEU1 */ |
| 61 | #else |
| 62 | tst %o2 /* IEU1 */ |
| 63 | be,pn %XCC, 12f /* CTI */ |
| 64 | #endif |
| 65 | sll %o1, 8, %g3 /* IEU0 Group */ |
| 66 | add %o0, %o2, %o2 /* IEU1 */ |
| 67 | |
| 68 | sethi %hi(0x01010101), %g1 /* IEU0 Group */ |
| 69 | or %g3, %o1, %g3 /* IEU1 */ |
| 70 | ldub [%o0], %o3 /* Load */ |
| 71 | sllx %g3, 16, %g5 /* IEU0 Group */ |
| 72 | |
| 73 | or %g1, %lo(0x01010101), %g1 /* IEU1 */ |
| 74 | sllx %g1, 32, %g2 /* IEU0 Group */ |
| 75 | or %g3, %g5, %g3 /* IEU1 */ |
| 76 | sllx %g3, 32, %g5 /* IEU0 Group */ |
| 77 | |
| 78 | cmp %o3, %o1 /* IEU1 */ |
| 79 | be,pn %xcc, 13f /* CTI */ |
| 80 | or %g1, %g2, %g1 /* IEU0 Group */ |
| 81 | andcc %o0, 7, %g0 /* IEU1 */ |
| 82 | |
| 83 | bne,a,pn %icc, 21f /* CTI */ |
| 84 | add %o0, 1, %o0 /* IEU0 Group */ |
| 85 | ldx [%o0], %o3 /* Load Group */ |
| 86 | sllx %g1, 7, %g2 /* IEU0 */ |
| 87 | |
| 88 | or %g3, %g5, %g3 /* IEU1 */ |
| 89 | 1: add %o0, 8, %o0 /* IEU0 Group */ |
| 90 | xor %o3, %g3, %o4 /* IEU1 */ |
| 91 | /* %g1 = 0101010101010101 * |
| 92 | * %g2 = 8080088080808080 * |
| 93 | * %g3 = c c c c c c c c * |
| 94 | * %o3 = value * |
| 95 | * %o4 = value XOR c */ |
| 96 | 2: cmp %o0, %o2 /* IEU1 Group */ |
| 97 | |
| 98 | bg,pn %XCC, 11f /* CTI */ |
| 99 | ldxa [%o0] ASI_PNF, %o3 /* Load */ |
| 100 | sub %o4, %g1, %o5 /* IEU0 Group */ |
| 101 | add %o0, 8, %o0 /* IEU1 */ |
| 102 | #ifdef EIGHTBIT_NOT_RARE |
| 103 | andn %o5, %o4, %o5 /* IEU0 Group */ |
| 104 | #endif |
| 105 | |
| 106 | andcc %o5, %g2, %g0 /* IEU1 Group */ |
| 107 | be,a,pt %xcc, 2b /* CTI */ |
| 108 | xor %o3, %g3, %o4 /* IEU0 */ |
| 109 | srlx %o4, 56, %g5 /* IEU0 */ |
| 110 | |
| 111 | andcc %g5, 0xff, %g0 /* IEU1 Group */ |
| 112 | be,pn %icc, 3f /* CTI */ |
| 113 | srlx %o4, 48, %g5 /* IEU0 */ |
| 114 | andcc %g5, 0xff, %g0 /* IEU1 Group */ |
| 115 | |
| 116 | be,pn %icc, 4f /* CTI */ |
| 117 | srlx %o4, 40, %g5 /* IEU0 */ |
| 118 | andcc %g5, 0xff, %g0 /* IEU1 Group */ |
| 119 | be,pn %icc, 5f /* CTI */ |
| 120 | |
| 121 | srlx %o4, 32, %g5 /* IEU0 */ |
| 122 | andcc %g5, 0xff, %g0 /* IEU1 Group */ |
| 123 | be,pn %icc, 6f /* CTI */ |
| 124 | srlx %o4, 24, %g5 /* IEU0 */ |
| 125 | |
| 126 | andcc %g5, 0xff, %g0 /* IEU1 Group */ |
| 127 | be,pn %icc, 7f /* CTI */ |
| 128 | srlx %o4, 16, %g5 /* IEU0 */ |
| 129 | andcc %g5, 0xff, %g0 /* IEU1 Group */ |
| 130 | |
| 131 | be,pn %icc, 8f /* CTI */ |
| 132 | srlx %o4, 8, %g5 /* IEU0 */ |
| 133 | andcc %g5, 0xff, %g0 /* IEU1 Group */ |
| 134 | be,pn %icc, 9f /* CTI */ |
| 135 | |
| 136 | andcc %o4, 0xff, %g0 /* IEU1 Group */ |
| 137 | bne,pt %icc, 2b /* CTI */ |
| 138 | xor %o3, %g3, %o4 /* IEU0 */ |
| 139 | retl /* CTI+IEU1 Group */ |
| 140 | |
| 141 | add %o0, -9, %o0 /* IEU0 */ |
| 142 | |
| 143 | .align 16 |
| 144 | 3: retl /* CTI+IEU1 Group */ |
| 145 | add %o0, -16, %o0 /* IEU0 */ |
| 146 | 4: retl /* CTI+IEU1 Group */ |
| 147 | add %o0, -15, %o0 /* IEU0 */ |
| 148 | |
| 149 | 5: retl /* CTI+IEU1 Group */ |
| 150 | add %o0, -14, %o0 /* IEU0 */ |
| 151 | 6: retl /* CTI+IEU1 Group */ |
| 152 | add %o0, -13, %o0 /* IEU0 */ |
| 153 | |
| 154 | 7: retl /* CTI+IEU1 Group */ |
| 155 | add %o0, -12, %o0 /* IEU0 */ |
| 156 | 8: retl /* CTI+IEU1 Group */ |
| 157 | add %o0, -11, %o0 /* IEU0 */ |
| 158 | |
| 159 | 9: retl /* CTI+IEU1 Group */ |
| 160 | add %o0, -10, %o0 /* IEU0 */ |
| 161 | 11: sub %o4, %g1, %o5 /* IEU0 Group */ |
| 162 | sub %o0, 8, %o0 /* IEU1 */ |
| 163 | |
| 164 | andcc %o5, %g2, %g0 /* IEU1 Group */ |
| 165 | be,pt %xcc, 12f /* CTI */ |
| 166 | sub %o2, %o0, %o2 /* IEU0 */ |
| 167 | tst %o2 /* IEU1 Group */ |
| 168 | |
| 169 | be,pn %XCC, 12f /* CTI */ |
| 170 | srlx %o4, 56, %g5 /* IEU0 */ |
| 171 | andcc %g5, 0xff, %g0 /* IEU1 Group */ |
| 172 | be,pn %icc, 13f /* CTI */ |
| 173 | |
| 174 | cmp %o2, 1 /* IEU0 */ |
| 175 | be,pn %XCC, 12f /* CTI Group */ |
| 176 | srlx %o4, 48, %g5 /* IEU0 */ |
| 177 | andcc %g5, 0xff, %g0 /* IEU1 Group */ |
| 178 | |
| 179 | be,pn %icc, 14f /* CTI */ |
| 180 | cmp %o2, 2 /* IEU1 Group */ |
| 181 | be,pn %XCC, 12f /* CTI */ |
| 182 | srlx %o4, 40, %g5 /* IEU0 */ |
| 183 | |
| 184 | andcc %g5, 0xff, %g0 /* IEU1 Group */ |
| 185 | be,pn %icc, 15f /* CTI */ |
| 186 | cmp %o2, 3 /* IEU1 Group */ |
| 187 | be,pn %XCC, 12f /* CTI */ |
| 188 | |
| 189 | srlx %o4, 32, %g5 /* IEU0 */ |
| 190 | andcc %g5, 0xff, %g0 /* IEU1 Group */ |
| 191 | be,pn %icc, 16f /* CTI */ |
| 192 | cmp %o2, 4 /* IEU1 Group */ |
| 193 | |
| 194 | be,pn %XCC, 12f /* CTI */ |
| 195 | srlx %o4, 24, %g5 /* IEU0 */ |
| 196 | andcc %g5, 0xff, %g0 /* IEU1 Group */ |
| 197 | be,pn %icc, 17f /* CTI */ |
| 198 | |
| 199 | cmp %o2, 5 /* IEU1 Group */ |
| 200 | be,pn %XCC, 12f /* CTI */ |
| 201 | srlx %o4, 16, %g5 /* IEU0 */ |
| 202 | andcc %g5, 0xff, %g0 /* IEU1 Group */ |
| 203 | |
| 204 | be,pn %icc, 18f /* CTI */ |
| 205 | cmp %o2, 6 /* IEU1 Group */ |
| 206 | be,pn %XCC, 12f /* CTI */ |
| 207 | srlx %o4, 8, %g5 /* IEU0 */ |
| 208 | |
| 209 | andcc %g5, 0xff, %g0 /* IEU1 Group */ |
| 210 | be,pn %icc, 19f /* CTI */ |
| 211 | nop /* IEU0 */ |
| 212 | 12: retl /* CTI+IEU1 Group */ |
| 213 | |
| 214 | clr %o0 /* IEU0 */ |
| 215 | nop /* Stub */ |
| 216 | 13: retl /* CTI+IEU1 Group */ |
| 217 | nop /* IEU0 */ |
| 218 | |
| 219 | 14: retl /* CTI+IEU1 Group */ |
| 220 | add %o0, 1, %o0 /* IEU0 */ |
| 221 | 15: retl /* CTI+IEU1 Group */ |
| 222 | add %o0, 2, %o0 /* IEU0 */ |
| 223 | |
| 224 | 16: retl /* CTI+IEU1 Group */ |
| 225 | add %o0, 3, %o0 /* IEU0 */ |
| 226 | 17: retl /* CTI+IEU1 Group */ |
| 227 | add %o0, 4, %o0 /* IEU0 */ |
| 228 | |
| 229 | 18: retl /* CTI+IEU1 Group */ |
| 230 | add %o0, 5, %o0 /* IEU0 */ |
| 231 | 19: retl /* CTI+IEU1 Group */ |
| 232 | add %o0, 6, %o0 /* IEU0 */ |
| 233 | |
| 234 | 21: cmp %o0, %o2 /* IEU1 */ |
| 235 | be,pn %XCC, 12b /* CTI */ |
| 236 | sllx %g1, 7, %g2 /* IEU0 Group */ |
| 237 | ldub [%o0], %o3 /* Load */ |
| 238 | |
| 239 | or %g3, %g5, %g3 /* IEU1 */ |
| 240 | 22: andcc %o0, 7, %g0 /* IEU1 Group */ |
| 241 | be,a,pn %icc, 1b /* CTI */ |
| 242 | ldx [%o0], %o3 /* Load */ |
| 243 | |
| 244 | cmp %o3, %o1 /* IEU1 Group */ |
| 245 | be,pn %xcc, 23f /* CTI */ |
| 246 | add %o0, 1, %o0 /* IEU0 */ |
| 247 | cmp %o0, %o2 /* IEU1 Group */ |
| 248 | |
| 249 | bne,a,pt %XCC, 22b /* CTI */ |
| 250 | ldub [%o0], %o3 /* Load */ |
| 251 | retl /* CTI+IEU1 Group */ |
| 252 | clr %o0 /* IEU0 */ |
| 253 | |
| 254 | 23: retl /* CTI+IEU1 Group */ |
| 255 | add %o0, -1, %o0 /* IEU0 */ |
| 256 | END(memchr) |
| 257 | |
| 258 | libc_hidden_def(memchr) |
| 259 | weak_alias(memchr,__ubp_memchr) |