arch/ppc/lib/ppcstring.S

   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 <ppc_asm.tmpl>
  12 #include <asm/errno.h>
  13
  14         .globl  strcpy
  15 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         .globl  strncpy
  25 strncpy:
  26         cmpwi   0,r5,0
  27         beqlr
  28         mtctr   r5
  29         addi    r6,r3,-1
  30         addi    r4,r4,-1
  31 1:      lbzu    r0,1(r4)
  32         cmpwi   0,r0,0
  33         stbu    r0,1(r6)
  34         bdnzf   2,1b            /* dec ctr, branch if ctr != 0 && !cr0.eq */
  35         blr
  36
  37         .globl  strcat
  38 strcat:
  39         addi    r5,r3,-1
  40         addi    r4,r4,-1
  41 1:      lbzu    r0,1(r5)
  42         cmpwi   0,r0,0
  43         bne     1b
  44         addi    r5,r5,-1
  45 1:      lbzu    r0,1(r4)
  46         cmpwi   0,r0,0
  47         stbu    r0,1(r5)
  48         bne     1b
  49         blr
  50
  51         .globl  strcmp
  52 strcmp:
  53         addi    r5,r3,-1
  54         addi    r4,r4,-1
  55 1:      lbzu    r3,1(r5)
  56         cmpwi   1,r3,0
  57         lbzu    r0,1(r4)
  58         subf.   r3,r0,r3
  59         beqlr   1
  60         beq     1b
  61         blr
  62
  63         .globl  strlen
  64 strlen:
  65         addi    r4,r3,-1
  66 1:      lbzu    r0,1(r4)
  67         cmpwi   0,r0,0
  68         bne     1b
  69         subf    r3,r3,r4
  70         blr
  71
  72         .globl  memset
  73 memset:
  74         rlwimi  r4,r4,8,16,23
  75         rlwimi  r4,r4,16,0,15
  76         addi    r6,r3,-4
  77         cmplwi  0,r5,4
  78         blt     7f
  79         stwu    r4,4(r6)
  80         beqlr
  81         andi.   r0,r6,3
  82         add     r5,r0,r5
  83         subf    r6,r0,r6
  84         rlwinm  r0,r5,32-2,2,31
  85         mtctr   r0
  86         bdz     6f
  87 1:      stwu    r4,4(r6)
  88         bdnz    1b
  89 6:      andi.   r5,r5,3
  90 7:      cmpwi   0,r5,0
  91         beqlr
  92         mtctr   r5
  93         addi    r6,r6,3
  94 8:      stbu    r4,1(r6)
  95         bdnz    8b
  96         blr
  97
  98         .globl  bcopy
  99 bcopy:
 100         mr      r6,r3
 101         mr      r3,r4
 102         mr      r4,r6
 103         b       memcpy
 104
 105         .globl  memmove
 106 memmove:
 107         cmplw   0,r3,r4
 108         bgt     backwards_memcpy
 109         /* fall through */
 110
 111         .globl  memcpy
 112 memcpy:
 113         rlwinm. r7,r5,32-3,3,31         /* r0 = r5 >> 3 */
 114         addi    r6,r3,-4
 115         addi    r4,r4,-4
 116         beq     2f                      /* if less than 8 bytes to do */
 117         andi.   r0,r6,3                 /* get dest word aligned */
 118         mtctr   r7
 119         bne     5f
 120 1:      lwz     r7,4(r4)
 121         lwzu    r8,8(r4)
 122         stw     r7,4(r6)
 123         stwu    r8,8(r6)
 124         bdnz    1b
 125         andi.   r5,r5,7
 126 2:      cmplwi  0,r5,4
 127         blt     3f
 128         lwzu    r0,4(r4)
 129         addi    r5,r5,-4
 130         stwu    r0,4(r6)
 131 3:      cmpwi   0,r5,0
 132         beqlr
 133         mtctr   r5
 134         addi    r4,r4,3
 135         addi    r6,r6,3
 136 4:      lbzu    r0,1(r4)
 137         stbu    r0,1(r6)
 138         bdnz    4b
 139         blr
 140 5:      subfic  r0,r0,4
 141         mtctr   r0
 142 6:      lbz     r7,4(r4)
 143         addi    r4,r4,1
 144         stb     r7,4(r6)
 145         addi    r6,r6,1
 146         bdnz    6b
 147         subf    r5,r0,r5
 148         rlwinm. r7,r5,32-3,3,31
 149         beq     2b
 150         mtctr   r7
 151         b       1b
 152
 153         .globl  backwards_memcpy
 154 backwards_memcpy:
 155         rlwinm. r7,r5,32-3,3,31         /* r0 = r5 >> 3 */
 156         add     r6,r3,r5
 157         add     r4,r4,r5
 158         beq     2f
 159         andi.   r0,r6,3
 160         mtctr   r7
 161         bne     5f
 162 1:      lwz     r7,-4(r4)
 163         lwzu    r8,-8(r4)
 164         stw     r7,-4(r6)
 165         stwu    r8,-8(r6)
 166         bdnz    1b
 167         andi.   r5,r5,7
 168 2:      cmplwi  0,r5,4
 169         blt     3f
 170         lwzu    r0,-4(r4)
 171         subi    r5,r5,4
 172         stwu    r0,-4(r6)
 173 3:      cmpwi   0,r5,0
 174         beqlr
 175         mtctr   r5
 176 4:      lbzu    r0,-1(r4)
 177         stbu    r0,-1(r6)
 178         bdnz    4b
 179         blr
 180 5:      mtctr   r0
 181 6:      lbzu    r7,-1(r4)
 182         stbu    r7,-1(r6)
 183         bdnz    6b
 184         subf    r5,r0,r5
 185         rlwinm. r7,r5,32-3,3,31
 186         beq     2b
 187         mtctr   r7
 188         b       1b
 189
 190         .globl  memcmp
 191 memcmp:
 192         cmpwi   0,r5,0
 193         ble-    2f
 194         mtctr   r5
 195         addi    r6,r3,-1
 196         addi    r4,r4,-1
 197 1:      lbzu    r3,1(r6)
 198         lbzu    r0,1(r4)
 199         subf.   r3,r0,r3
 200         bdnzt   2,1b
 201         blr
 202 2:      li      r3,0
 203         blr
 204
 205         .global memchr
 206 memchr:
 207         cmpwi   0,r5,0
 208         ble-    2f
 209         mtctr   r5
 210         addi    r3,r3,-1
 211 1:      lbzu    r0,1(r3)
 212         cmpw    0,r0,r4
 213         bdnzf   2,1b
 214         beqlr
 215 2:      li      r3,0
 216         blr