| Paul Mackerras | 14cf11a | 2005-09-26 16:04:21 +1000 | [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 | */ |
| Paul Mackerras | 14cf11a | 2005-09-26 16:04:21 +1000 | [diff] [blame] | 11 | #include <asm/processor.h> |
| 12 | #include <asm/errno.h> |
| 13 | #include <asm/ppc_asm.h> |
| 14 | |
| Paul Mackerras | 14cf11a | 2005-09-26 16:04:21 +1000 | [diff] [blame] | 15 | .section __ex_table,"a" |
| Michael Ellerman | 76bfdcf | 2008-07-17 17:17:52 +1000 | [diff] [blame] | 16 | PPC_LONG_ALIGN |
| Paul Mackerras | 14cf11a | 2005-09-26 16:04:21 +1000 | [diff] [blame] | 17 | .text |
| 18 | |
| 19 | _GLOBAL(strcpy) |
| 20 | addi r5,r3,-1 |
| 21 | addi r4,r4,-1 |
| 22 | 1: lbzu r0,1(r4) |
| 23 | cmpwi 0,r0,0 |
| 24 | stbu r0,1(r5) |
| 25 | bne 1b |
| 26 | blr |
| 27 | |
| 28 | /* This clears out any unused part of the destination buffer, |
| 29 | just as the libc version does. -- paulus */ |
| 30 | _GLOBAL(strncpy) |
| 31 | cmpwi 0,r5,0 |
| 32 | beqlr |
| 33 | mtctr r5 |
| 34 | addi r6,r3,-1 |
| 35 | addi r4,r4,-1 |
| 36 | 1: lbzu r0,1(r4) |
| 37 | cmpwi 0,r0,0 |
| 38 | stbu r0,1(r6) |
| 39 | bdnzf 2,1b /* dec ctr, branch if ctr != 0 && !cr0.eq */ |
| 40 | bnelr /* if we didn't hit a null char, we're done */ |
| 41 | mfctr r5 |
| 42 | cmpwi 0,r5,0 /* any space left in destination buffer? */ |
| 43 | beqlr /* we know r0 == 0 here */ |
| 44 | 2: stbu r0,1(r6) /* clear it out if so */ |
| 45 | bdnz 2b |
| 46 | blr |
| 47 | |
| 48 | _GLOBAL(strcat) |
| 49 | addi r5,r3,-1 |
| 50 | addi r4,r4,-1 |
| 51 | 1: lbzu r0,1(r5) |
| 52 | cmpwi 0,r0,0 |
| 53 | bne 1b |
| 54 | addi r5,r5,-1 |
| 55 | 1: lbzu r0,1(r4) |
| 56 | cmpwi 0,r0,0 |
| 57 | stbu r0,1(r5) |
| 58 | bne 1b |
| 59 | blr |
| 60 | |
| 61 | _GLOBAL(strcmp) |
| 62 | addi r5,r3,-1 |
| 63 | addi r4,r4,-1 |
| 64 | 1: lbzu r3,1(r5) |
| 65 | cmpwi 1,r3,0 |
| 66 | lbzu r0,1(r4) |
| 67 | subf. r3,r0,r3 |
| 68 | beqlr 1 |
| 69 | beq 1b |
| 70 | blr |
| 71 | |
| Steven Rostedt | 0119536 | 2008-03-01 03:04:57 +1100 | [diff] [blame] | 72 | _GLOBAL(strncmp) |
| 73 | PPC_LCMPI r5,0 |
| 74 | beqlr |
| 75 | mtctr r5 |
| 76 | addi r5,r3,-1 |
| 77 | addi r4,r4,-1 |
| 78 | 1: lbzu r3,1(r5) |
| 79 | cmpwi 1,r3,0 |
| 80 | lbzu r0,1(r4) |
| 81 | subf. r3,r0,r3 |
| 82 | beqlr 1 |
| 83 | bdnzt eq,1b |
| 84 | blr |
| 85 | |
| Paul Mackerras | 14cf11a | 2005-09-26 16:04:21 +1000 | [diff] [blame] | 86 | _GLOBAL(strlen) |
| 87 | addi r4,r3,-1 |
| 88 | 1: lbzu r0,1(r4) |
| 89 | cmpwi 0,r0,0 |
| 90 | bne 1b |
| 91 | subf r3,r3,r4 |
| 92 | blr |
| 93 | |
| 94 | _GLOBAL(memcmp) |
| 95 | cmpwi 0,r5,0 |
| 96 | ble- 2f |
| 97 | mtctr r5 |
| 98 | addi r6,r3,-1 |
| 99 | addi r4,r4,-1 |
| 100 | 1: lbzu r3,1(r6) |
| 101 | lbzu r0,1(r4) |
| 102 | subf. r3,r0,r3 |
| 103 | bdnzt 2,1b |
| 104 | blr |
| 105 | 2: li r3,0 |
| 106 | blr |
| 107 | |
| 108 | _GLOBAL(memchr) |
| 109 | cmpwi 0,r5,0 |
| 110 | ble- 2f |
| 111 | mtctr r5 |
| 112 | addi r3,r3,-1 |
| 113 | 1: lbzu r0,1(r3) |
| 114 | cmpw 0,r0,r4 |
| 115 | bdnzf 2,1b |
| 116 | beqlr |
| 117 | 2: li r3,0 |
| 118 | blr |
| 119 | |
| 120 | _GLOBAL(__clear_user) |
| 121 | addi r6,r3,-4 |
| 122 | li r3,0 |
| 123 | li r5,0 |
| 124 | cmplwi 0,r4,4 |
| 125 | blt 7f |
| 126 | /* clear a single word */ |
| 127 | 11: stwu r5,4(r6) |
| 128 | beqlr |
| 129 | /* clear word sized chunks */ |
| 130 | andi. r0,r6,3 |
| 131 | add r4,r0,r4 |
| 132 | subf r6,r0,r6 |
| 133 | srwi r0,r4,2 |
| 134 | andi. r4,r4,3 |
| 135 | mtctr r0 |
| 136 | bdz 7f |
| 137 | 1: stwu r5,4(r6) |
| 138 | bdnz 1b |
| 139 | /* clear byte sized chunks */ |
| 140 | 7: cmpwi 0,r4,0 |
| 141 | beqlr |
| 142 | mtctr r4 |
| 143 | addi r6,r6,3 |
| 144 | 8: stbu r5,1(r6) |
| 145 | bdnz 8b |
| 146 | blr |
| 147 | 90: mr r3,r4 |
| 148 | blr |
| 149 | 91: mfctr r3 |
| 150 | slwi r3,r3,2 |
| 151 | add r3,r3,r4 |
| 152 | blr |
| 153 | 92: mfctr r3 |
| 154 | blr |
| 155 | |
| 156 | .section __ex_table,"a" |
| Michael Ellerman | 76bfdcf | 2008-07-17 17:17:52 +1000 | [diff] [blame] | 157 | PPC_LONG 11b,90b |
| 158 | PPC_LONG 1b,91b |
| 159 | PPC_LONG 8b,92b |
| Paul Mackerras | 14cf11a | 2005-09-26 16:04:21 +1000 | [diff] [blame] | 160 | .text |
| 161 | |
| 162 | _GLOBAL(__strncpy_from_user) |
| 163 | addi r6,r3,-1 |
| 164 | addi r4,r4,-1 |
| 165 | cmpwi 0,r5,0 |
| 166 | beq 2f |
| 167 | mtctr r5 |
| 168 | 1: lbzu r0,1(r4) |
| 169 | cmpwi 0,r0,0 |
| 170 | stbu r0,1(r6) |
| 171 | bdnzf 2,1b /* dec ctr, branch if ctr != 0 && !cr0.eq */ |
| 172 | beq 3f |
| 173 | 2: addi r6,r6,1 |
| 174 | 3: subf r3,r3,r6 |
| 175 | blr |
| 176 | 99: li r3,-EFAULT |
| 177 | blr |
| 178 | |
| 179 | .section __ex_table,"a" |
| Michael Ellerman | 76bfdcf | 2008-07-17 17:17:52 +1000 | [diff] [blame] | 180 | PPC_LONG 1b,99b |
| Paul Mackerras | 14cf11a | 2005-09-26 16:04:21 +1000 | [diff] [blame] | 181 | .text |
| 182 | |
| 183 | /* r3 = str, r4 = len (> 0), r5 = top (highest addr) */ |
| 184 | _GLOBAL(__strnlen_user) |
| 185 | addi r7,r3,-1 |
| 186 | subf r6,r7,r5 /* top+1 - str */ |
| 187 | cmplw 0,r4,r6 |
| 188 | bge 0f |
| 189 | mr r6,r4 |
| 190 | 0: mtctr r6 /* ctr = min(len, top - str) */ |
| 191 | 1: lbzu r0,1(r7) /* get next byte */ |
| 192 | cmpwi 0,r0,0 |
| 193 | bdnzf 2,1b /* loop if --ctr != 0 && byte != 0 */ |
| 194 | addi r7,r7,1 |
| 195 | subf r3,r3,r7 /* number of bytes we have looked at */ |
| 196 | beqlr /* return if we found a 0 byte */ |
| 197 | cmpw 0,r3,r4 /* did we look at all len bytes? */ |
| 198 | blt 99f /* if not, must have hit top */ |
| 199 | addi r3,r4,1 /* return len + 1 to indicate no null found */ |
| 200 | blr |
| 201 | 99: li r3,0 /* bad address, return 0 */ |
| 202 | blr |
| 203 | |
| 204 | .section __ex_table,"a" |
| Michael Ellerman | 76bfdcf | 2008-07-17 17:17:52 +1000 | [diff] [blame] | 205 | PPC_LONG 1b,99b |