sysdeps/sparc/sparc32/strchr.S

   1 /* strchr (str, ch) -- Return pointer to first occurrence of CH in STR.
   2    For SPARC v7.
   3    Copyright (C) 1996-2019 Free Software Foundation, Inc.
   4    This file is part of the GNU C Library.
   5    Contributed by Jakub Jelinek <jj@ultra.linux.cz> and
   6                   David S. Miller <davem@caip.rutgers.edu>.
   7
   8    The GNU C Library is free software; you can redistribute it and/or
   9    modify it under the terms of the GNU Lesser General Public
  10    License as published by the Free Software Foundation; either
  11    version 2.1 of the License, or (at your option) any later version.
  12
  13    The GNU C Library is distributed in the hope that it will be useful,
  14    but WITHOUT ANY WARRANTY; without even the implied warranty of
  15    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
  16    Lesser General Public License for more details.
  17
  18    You should have received a copy of the GNU Lesser General Public
  19    License along with the GNU C Library; if not, see
  20    <http://www.gnu.org/licenses/>.  */
  21
  22 #include <sysdep.h>
  23
  24         /* Normally, this uses ((xword - 0x01010101) & 0x80808080) test
  25            to find out if any byte in xword could be zero. This is fast, but
  26            also gives false alarm for any byte in range 0x81-0xff. It does
  27            not matter for correctness, as if this test tells us there could
  28            be some zero byte, we check it byte by byte, but if bytes with
  29            high bits set are common in the strings, then this will give poor
  30            performance. You can #define EIGHTBIT_NOT_RARE and the algorithm
  31            will use one tick slower, but more precise test
  32            ((xword - 0x01010101) & (~xword) & 0x80808080),
  33            which does not give any false alarms (but if some bits are set,
  34            one cannot assume from it which bytes are zero and which are not).
  35            It is yet to be measured, what is the correct default for glibc
  36            in these days for an average user.
  37          */
  38
  39         .text
  40         .align          4
  41 ENTRY(strchr)
  42         andcc           %o1, 0xff, %o1
  43         be              12f
  44          sll            %o1, 8, %o2
  45         andcc           %o0, 3, %g0
  46         or              %o1, %o2, %o2
  47         sethi           %hi(0x80808080), %o4
  48         sll             %o2, 16, %o3
  49         be              13f
  50          or             %o3, %o2, %g2
  51
  52         ldub            [%o0], %g4
  53         cmp             %g4, %o1
  54         be              11f
  55          add            %o0, 1, %o0
  56         cmp             %g4, 0
  57         be              9f
  58          andcc          %o0, 3, %g0
  59         be              4f
  60          or             %o4, %lo(0x80808080), %o3
  61         ldub            [%o0], %g4
  62         cmp             %g4, %o1
  63         be              11f
  64          add            %o0, 1, %o0
  65         cmp             %g4, 0
  66         be              9f
  67          andcc          %o0, 3, %g0
  68         be              5f
  69          sethi          %hi(0x01010101), %o5
  70         ldub            [%o0], %g4
  71         cmp             %g4, %o1
  72         be              11f
  73          add            %o0, 1, %o0
  74         cmp             %g4, 0
  75         be              9f
  76          or             %o5, %lo(0x01010101), %o2
  77         b               6f
  78          ld             [%o0], %g4
  79 11:     retl
  80          sub            %o0, 1, %o0
  81
  82 13:     or              %o4, %lo(0x80808080), %o3
  83 4:      sethi           %hi(0x01010101), %o5
  84 5:      or              %o5, %lo(0x01010101), %o2
  85 7:      ld              [%o0], %g4
  86 6:      xor             %g4, %g2, %g5
  87         sub             %g4, %o2, %o4
  88 #ifdef EIGHTBIT_NOT_RARE
  89         sub             %g5, %o2, %g6
  90         andn            %o4, %g4, %o4
  91         andn            %g6, %g5, %g5
  92 #else
  93         sub             %g5, %o2, %g5
  94 #endif
  95         or              %g5, %o4, %o4
  96         andcc           %o4, %o3, %g0
  97         be              7b
  98          add            %o0, 4, %o0
  99
 100         /* Check every byte. */
 101 8:      srl             %g4, 24, %g5
 102 7:      andcc           %g5, 0xff, %g5
 103         be              9f
 104          cmp            %g5, %o1
 105         be              4f
 106          srl            %g4, 16, %g5
 107         andcc           %g5, 0xff, %g5
 108         be              9f
 109          cmp            %g5, %o1
 110         be              3f
 111          srl            %g4, 8, %g5
 112         andcc           %g5, 0xff, %g5
 113         be              9f
 114          cmp            %g5, %o1
 115         be              2f
 116          andcc          %g4, 0xff, %g5
 117         be              9f
 118          cmp            %g5, %o1
 119         bne,a           6b
 120          ld             [%o0], %g4
 121         retl
 122          sub            %o0, 1, %o0
 123 2:      retl
 124          sub            %o0, 2, %o0
 125 3:      retl
 126          sub            %o0, 3, %o0
 127 4:      retl
 128          sub            %o0, 4, %o0
 129 9:      retl
 130          clr            %o0
 131
 132 11:     ldub            [%o0], %o5
 133         cmp             %o5, 0
 134         be              1f
 135          add            %o0, 1, %o0
 136         andcc           %o0, 3, %g0
 137         be              4f
 138          or             %o4, %lo(0x80808080), %o3
 139         ldub            [%o0], %o5
 140         cmp             %o5, 0
 141         be              1f
 142          add            %o0, 1, %o0
 143         andcc           %o0, 3, %g0
 144         be              5f
 145          sethi          %hi(0x01010101), %o4
 146         ldub            [%o0], %o5
 147         cmp             %o5, 0
 148         be              1f
 149          add            %o0, 1, %o0
 150         b               6f
 151          or             %o4, %lo(0x01010101), %o2
 152 1:      retl
 153          sub            %o0, 1, %o0
 154
 155 12:     andcc           %o0, 3, %g0
 156         bne             11b
 157          sethi          %hi(0x80808080), %o4
 158         or              %o4, %lo(0x80808080), %o3
 159 4:      sethi           %hi(0x01010101), %o4
 160 5:      or              %o4, %lo(0x01010101), %o2
 161 6:      ld              [%o0], %o5
 162 7:      sub             %o5, %o2, %o4
 163 #ifdef EIGHTBIT_NOT_RARE
 164         andn            %o4, %o5, %o4
 165 #endif
 166         andcc           %o4, %o3, %g0
 167         be              6b
 168          add            %o0, 4, %o0
 169
 170         /* Check every byte. */
 171         srl             %o5, 24, %g5
 172         andcc           %g5, 0xff, %g0
 173         be              8f
 174          add            %o0, -4, %o4
 175         srl             %o5, 16, %g5
 176         andcc           %g5, 0xff, %g0
 177         be              8f
 178          add            %o4, 1, %o4
 179         srl             %o5, 8, %g5
 180         andcc           %g5, 0xff, %g0
 181         be              8f
 182          add            %o4, 1, %o4
 183         andcc           %o5, 0xff, %g0
 184         bne,a           7b
 185          ld             [%o0], %o5
 186         add             %o4, 1, %o4
 187 8:      retl
 188          mov            %o4, %o0
 189
 190 13:     ldub            [%o0], %g4
 191         cmp             %g4, %o1
 192         add             %o0, 1, %o0
 193         be,a            1f
 194          sub            %o0, 1, %o5
 195         cmp             %g4, 0
 196         be              9f
 197 1:       andcc          %o0, 3, %g0
 198         be              4f
 199          or             %o4, %lo(0x80808080), %o3
 200         ldub            [%o0], %g4
 201         cmp             %g4, %o1
 202         add             %o0, 1, %o0
 203         be,a            1f
 204          sub            %o0, 1, %o5
 205         cmp             %g4, 0
 206         be              9f
 207 1:       andcc          %o0, 3, %g0
 208         be              5f
 209          sethi          %hi(0x01010101), %o4
 210         ldub            [%o0], %g4
 211         cmp             %g4, %o1
 212         add             %o0, 1, %o0
 213         be,a            1f
 214          sub            %o0, 1, %o5
 215         cmp             %g4, 0
 216         be              9f
 217 1:       or             %o4, %lo(0x01010101), %o2
 218         b               7f
 219          ld             [%o0], %g4
 220 END(strchr)
 221
 222 ENTRY(strrchr)
 223         andcc           %o1, 0xff, %o1
 224         clr             %o5
 225         be              12b
 226          sll            %o1, 8, %o2
 227         andcc           %o0, 3, %g0
 228         or              %o1, %o2, %o2
 229         sethi           %hi(0x80808080), %o4
 230         sll             %o2, 16, %o3
 231         bne             13b
 232          or             %o3, %o2, %g2
 233         or              %o4, %lo(0x80808080), %o3
 234 4:      sethi           %hi(0x01010101), %o4
 235 5:      or              %o4, %lo(0x01010101), %o2
 236 6:      ld              [%o0], %g4
 237 7:      xor             %g4, %g2, %g5
 238         sub             %g4, %o2, %o4
 239 #ifdef EIGHTBIT_NOT_RARE
 240         sub             %g5, %o2, %g6
 241         andn            %o4, %g4, %o4
 242         andn            %g6, %g5, %g5
 243 #else
 244         sub             %g5, %o2, %g5
 245 #endif
 246         or              %g5, %o4, %o4
 247         andcc           %o4, %o3, %g0
 248         be              6b
 249          add            %o0, 4, %o0
 250
 251         /* Check every byte. */
 252 3:      srl             %g4, 24, %g5
 253 8:      andcc           %g5, 0xff, %g5
 254         be              9f
 255          cmp            %g5, %o1
 256         be,a            1f
 257          sub            %o0, 4, %o5
 258 1:      srl             %g4, 16, %g5
 259         andcc           %g5, 0xff, %g5
 260         be              9f
 261          cmp            %g5, %o1
 262         be,a            1f
 263          sub            %o0, 3, %o5
 264 1:      srl             %g4, 8, %g5
 265         andcc           %g5, 0xff, %g5
 266         be              9f
 267          cmp            %g5, %o1
 268         be,a            1f
 269          sub            %o0, 2, %o5
 270 1:      andcc           %g4, 0xff, %g5
 271         be              9f
 272          cmp            %g5, %o1
 273         be,a            1f
 274          sub            %o0, 1, %o5
 275 1:      b               7b
 276          ld             [%o0], %g4
 277 9:      retl
 278          mov            %o5, %o0
 279 END(strrchr)
 280
 281 weak_alias (strchr, index)
 282 weak_alias (strrchr, rindex)
 283 libc_hidden_builtin_def (strchr)
 284 libc_hidden_builtin_def (strrchr)