| Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame^] | 1 | /* |
| 2 | * String handling functions for PowerPC. |
| 3 | * |
| 4 | * Copyright (C) 1996 Paul Mackerras. |
| 5 | * |
| 6 | * This program is free software; you can redistribute it and/or |
| 7 | * modify it under the terms of the GNU General Public License |
| 8 | * as published by the Free Software Foundation; either version |
| 9 | * 2 of the License, or (at your option) any later version. |
| 10 | */ |
| 11 | #include <asm/processor.h> |
| 12 | #include <asm/errno.h> |
| 13 | #include <asm/ppc_asm.h> |
| 14 | |
| 15 | _GLOBAL(strcpy) |
| 16 | addi r5,r3,-1 |
| 17 | addi r4,r4,-1 |
| 18 | 1: lbzu r0,1(r4) |
| 19 | cmpwi 0,r0,0 |
| 20 | stbu r0,1(r5) |
| 21 | bne 1b |
| 22 | blr |
| 23 | |
| 24 | _GLOBAL(strncpy) |
| 25 | cmpwi 0,r5,0 |
| 26 | beqlr |
| 27 | mtctr r5 |
| 28 | addi r6,r3,-1 |
| 29 | addi r4,r4,-1 |
| 30 | 1: lbzu r0,1(r4) |
| 31 | cmpwi 0,r0,0 |
| 32 | stbu r0,1(r6) |
| 33 | bdnzf 2,1b /* dec ctr, branch if ctr != 0 && !cr0.eq */ |
| 34 | blr |
| 35 | |
| 36 | _GLOBAL(strcat) |
| 37 | addi r5,r3,-1 |
| 38 | addi r4,r4,-1 |
| 39 | 1: lbzu r0,1(r5) |
| 40 | cmpwi 0,r0,0 |
| 41 | bne 1b |
| 42 | addi r5,r5,-1 |
| 43 | 1: lbzu r0,1(r4) |
| 44 | cmpwi 0,r0,0 |
| 45 | stbu r0,1(r5) |
| 46 | bne 1b |
| 47 | blr |
| 48 | |
| 49 | _GLOBAL(strcmp) |
| 50 | addi r5,r3,-1 |
| 51 | addi r4,r4,-1 |
| 52 | 1: lbzu r3,1(r5) |
| 53 | cmpwi 1,r3,0 |
| 54 | lbzu r0,1(r4) |
| 55 | subf. r3,r0,r3 |
| 56 | beqlr 1 |
| 57 | beq 1b |
| 58 | blr |
| 59 | |
| 60 | _GLOBAL(strlen) |
| 61 | addi r4,r3,-1 |
| 62 | 1: lbzu r0,1(r4) |
| 63 | cmpwi 0,r0,0 |
| 64 | bne 1b |
| 65 | subf r3,r3,r4 |
| 66 | blr |
| 67 | |
| 68 | _GLOBAL(memset) |
| 69 | neg r0,r3 |
| 70 | rlwimi r4,r4,8,16,23 |
| 71 | andi. r0,r0,7 /* # bytes to be 8-byte aligned */ |
| 72 | rlwimi r4,r4,16,0,15 |
| 73 | cmplw cr1,r5,r0 /* do we get that far? */ |
| 74 | rldimi r4,r4,32,0 |
| 75 | mtcrf 1,r0 |
| 76 | mr r6,r3 |
| 77 | blt cr1,8f |
| 78 | beq+ 3f /* if already 8-byte aligned */ |
| 79 | subf r5,r0,r5 |
| 80 | bf 31,1f |
| 81 | stb r4,0(r6) |
| 82 | addi r6,r6,1 |
| 83 | 1: bf 30,2f |
| 84 | sth r4,0(r6) |
| 85 | addi r6,r6,2 |
| 86 | 2: bf 29,3f |
| 87 | stw r4,0(r6) |
| 88 | addi r6,r6,4 |
| 89 | 3: srdi. r0,r5,6 |
| 90 | clrldi r5,r5,58 |
| 91 | mtctr r0 |
| 92 | beq 5f |
| 93 | 4: std r4,0(r6) |
| 94 | std r4,8(r6) |
| 95 | std r4,16(r6) |
| 96 | std r4,24(r6) |
| 97 | std r4,32(r6) |
| 98 | std r4,40(r6) |
| 99 | std r4,48(r6) |
| 100 | std r4,56(r6) |
| 101 | addi r6,r6,64 |
| 102 | bdnz 4b |
| 103 | 5: srwi. r0,r5,3 |
| 104 | clrlwi r5,r5,29 |
| 105 | mtcrf 1,r0 |
| 106 | beq 8f |
| 107 | bf 29,6f |
| 108 | std r4,0(r6) |
| 109 | std r4,8(r6) |
| 110 | std r4,16(r6) |
| 111 | std r4,24(r6) |
| 112 | addi r6,r6,32 |
| 113 | 6: bf 30,7f |
| 114 | std r4,0(r6) |
| 115 | std r4,8(r6) |
| 116 | addi r6,r6,16 |
| 117 | 7: bf 31,8f |
| 118 | std r4,0(r6) |
| 119 | addi r6,r6,8 |
| 120 | 8: cmpwi r5,0 |
| 121 | mtcrf 1,r5 |
| 122 | beqlr+ |
| 123 | bf 29,9f |
| 124 | stw r4,0(r6) |
| 125 | addi r6,r6,4 |
| 126 | 9: bf 30,10f |
| 127 | sth r4,0(r6) |
| 128 | addi r6,r6,2 |
| 129 | 10: bflr 31 |
| 130 | stb r4,0(r6) |
| 131 | blr |
| 132 | |
| 133 | _GLOBAL(memmove) |
| 134 | cmplw 0,r3,r4 |
| 135 | bgt .backwards_memcpy |
| 136 | b .memcpy |
| 137 | |
| 138 | _GLOBAL(backwards_memcpy) |
| 139 | rlwinm. r7,r5,32-3,3,31 /* r0 = r5 >> 3 */ |
| 140 | add r6,r3,r5 |
| 141 | add r4,r4,r5 |
| 142 | beq 2f |
| 143 | andi. r0,r6,3 |
| 144 | mtctr r7 |
| 145 | bne 5f |
| 146 | 1: lwz r7,-4(r4) |
| 147 | lwzu r8,-8(r4) |
| 148 | stw r7,-4(r6) |
| 149 | stwu r8,-8(r6) |
| 150 | bdnz 1b |
| 151 | andi. r5,r5,7 |
| 152 | 2: cmplwi 0,r5,4 |
| 153 | blt 3f |
| 154 | lwzu r0,-4(r4) |
| 155 | subi r5,r5,4 |
| 156 | stwu r0,-4(r6) |
| 157 | 3: cmpwi 0,r5,0 |
| 158 | beqlr |
| 159 | mtctr r5 |
| 160 | 4: lbzu r0,-1(r4) |
| 161 | stbu r0,-1(r6) |
| 162 | bdnz 4b |
| 163 | blr |
| 164 | 5: mtctr r0 |
| 165 | 6: lbzu r7,-1(r4) |
| 166 | stbu r7,-1(r6) |
| 167 | bdnz 6b |
| 168 | subf r5,r0,r5 |
| 169 | rlwinm. r7,r5,32-3,3,31 |
| 170 | beq 2b |
| 171 | mtctr r7 |
| 172 | b 1b |
| 173 | |
| 174 | _GLOBAL(memcmp) |
| 175 | cmpwi 0,r5,0 |
| 176 | ble- 2f |
| 177 | mtctr r5 |
| 178 | addi r6,r3,-1 |
| 179 | addi r4,r4,-1 |
| 180 | 1: lbzu r3,1(r6) |
| 181 | lbzu r0,1(r4) |
| 182 | subf. r3,r0,r3 |
| 183 | bdnzt 2,1b |
| 184 | blr |
| 185 | 2: li r3,0 |
| 186 | blr |
| 187 | |
| 188 | _GLOBAL(memchr) |
| 189 | cmpwi 0,r5,0 |
| 190 | ble- 2f |
| 191 | mtctr r5 |
| 192 | addi r3,r3,-1 |
| 193 | 1: lbzu r0,1(r3) |
| 194 | cmpw 0,r0,r4 |
| 195 | bdnzf 2,1b |
| 196 | beqlr |
| 197 | 2: li r3,0 |
| 198 | blr |
| 199 | |
| 200 | _GLOBAL(__clear_user) |
| 201 | addi r6,r3,-4 |
| 202 | li r3,0 |
| 203 | li r5,0 |
| 204 | cmplwi 0,r4,4 |
| 205 | blt 7f |
| 206 | /* clear a single word */ |
| 207 | 11: stwu r5,4(r6) |
| 208 | beqlr |
| 209 | /* clear word sized chunks */ |
| 210 | andi. r0,r6,3 |
| 211 | add r4,r0,r4 |
| 212 | subf r6,r0,r6 |
| 213 | srwi r0,r4,2 |
| 214 | andi. r4,r4,3 |
| 215 | mtctr r0 |
| 216 | bdz 7f |
| 217 | 1: stwu r5,4(r6) |
| 218 | bdnz 1b |
| 219 | /* clear byte sized chunks */ |
| 220 | 7: cmpwi 0,r4,0 |
| 221 | beqlr |
| 222 | mtctr r4 |
| 223 | addi r6,r6,3 |
| 224 | 8: stbu r5,1(r6) |
| 225 | bdnz 8b |
| 226 | blr |
| 227 | 90: mr r3,r4 |
| 228 | blr |
| 229 | 91: mfctr r3 |
| 230 | slwi r3,r3,2 |
| 231 | add r3,r3,r4 |
| 232 | blr |
| 233 | 92: mfctr r3 |
| 234 | blr |
| 235 | |
| 236 | .section __ex_table,"a" |
| 237 | .align 3 |
| 238 | .llong 11b,90b |
| 239 | .llong 1b,91b |
| 240 | .llong 8b,92b |
| 241 | .text |
| 242 | |
| 243 | /* r3 = dst, r4 = src, r5 = count */ |
| 244 | _GLOBAL(__strncpy_from_user) |
| 245 | addi r6,r3,-1 |
| 246 | addi r4,r4,-1 |
| 247 | cmpwi 0,r5,0 |
| 248 | beq 2f |
| 249 | mtctr r5 |
| 250 | 1: lbzu r0,1(r4) |
| 251 | cmpwi 0,r0,0 |
| 252 | stbu r0,1(r6) |
| 253 | bdnzf 2,1b /* dec ctr, branch if ctr != 0 && !cr0.eq */ |
| 254 | beq 3f |
| 255 | 2: addi r6,r6,1 |
| 256 | 3: subf r3,r3,r6 |
| 257 | blr |
| 258 | 99: li r3,-EFAULT |
| 259 | blr |
| 260 | |
| 261 | .section __ex_table,"a" |
| 262 | .align 3 |
| 263 | .llong 1b,99b |
| 264 | .text |
| 265 | |
| 266 | /* r3 = str, r4 = len (> 0) */ |
| 267 | _GLOBAL(__strnlen_user) |
| 268 | addi r7,r3,-1 |
| 269 | mtctr r4 /* ctr = len */ |
| 270 | 1: lbzu r0,1(r7) /* get next byte */ |
| 271 | cmpwi 0,r0,0 |
| 272 | bdnzf 2,1b /* loop if --ctr != 0 && byte != 0 */ |
| 273 | addi r7,r7,1 |
| 274 | subf r3,r3,r7 /* number of bytes we have looked at */ |
| 275 | beqlr /* return if we found a 0 byte */ |
| 276 | cmpw 0,r3,r4 /* did we look at all len bytes? */ |
| 277 | blt 99f /* if not, must have hit top */ |
| 278 | addi r3,r4,1 /* return len + 1 to indicate no null found */ |
| 279 | blr |
| 280 | 99: li r3,0 /* bad address, return 0 */ |
| 281 | blr |
| 282 | |
| 283 | .section __ex_table,"a" |
| 284 | .align 3 |
| 285 | .llong 1b,99b |