sysdeps/sparc/sparc32/strlen.S

   1 /* Determine the length of a string.
   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@davemloft.net>.
   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    <https://www.gnu.org/licenses/>.  */
  21
  22 #include <sysdep.h>
  23
  24         .text
  25         .align          4
  26
  27 ENTRY(strlen)
  28         mov     %o0, %o1
  29         andn    %o0, 0x3, %o0
  30
  31         ld      [%o0], %o5
  32         and     %o1, 0x3, %g1
  33         mov     -1, %g5
  34
  35         sethi   %hi(0x01010101), %o2
  36         sll     %g1, 3, %g1
  37
  38         or      %o2, %lo(0x01010101), %o2
  39         srl     %g5, %g1, %g2
  40
  41         orn     %o5, %g2, %o5
  42         sll     %o2, 7, %o3
  43 10:     add     %o0, 4, %o0
  44
  45         andn    %o3, %o5, %g1
  46         sub     %o5, %o2, %g2
  47
  48         andcc   %g1, %g2, %g0
  49         be,a    10b
  50          ld     [%o0], %o5
  51
  52         srl     %o5, 24, %g1
  53
  54         andcc   %g1, 0xff, %g0
  55         be      90f
  56          sub    %o0, 4, %o0
  57
  58         srl     %o5, 16, %g2
  59
  60         andcc   %g2, 0xff, %g0
  61         be      90f
  62          add    %o0, 1, %o0
  63
  64         srl     %o5, 8, %g1
  65
  66         andcc   %g1, 0xff, %g0
  67         be      90f
  68          add    %o0, 1, %o0
  69
  70         add     %o0, 1, %o0
  71
  72 90:     retl
  73          sub    %o0, %o1, %o0
  74 END(strlen)
  75 libc_hidden_builtin_def (strlen)