sysdeps/alpha/alphaev67/ffs.S

   1 /* Copyright (C) 2000-2019 Free Software Foundation, Inc.
   2    This file is part of the GNU C Library.
   3
   4    The GNU C Library is free software; you can redistribute it and/or
   5    modify it under the terms of the GNU Lesser General Public
   6    License as published by the Free Software Foundation; either
   7    version 2.1 of the License, or (at your option) any later version.
   8
   9    The GNU C Library is distributed in the hope that it will be useful,
  10    but WITHOUT ANY WARRANTY; without even the implied warranty of
  11    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
  12    Lesser General Public License for more details.
  13
  14    You should have received a copy of the GNU Lesser General Public
  15    License along with the GNU C Library.  If not, see
  16    <https://www.gnu.org/licenses/>.  */
  17
  18 /* Finds the first bit set in an integer.  */
  19
  20 #include <sysdep.h>
  21
  22         .arch ev6
  23         .set noreorder
  24         .set noat
  25
  26
  27 ENTRY(__ffs)
  28 #ifdef PROF
  29         ldgp    gp, 0(pv)
  30         lda     AT, _mcount
  31         jsr     AT, (AT), _mcount
  32         .prologue 1
  33 #else
  34         .prologue 0
  35 #endif
  36
  37         zap     $16, 0xF0, $16
  38         cttz    $16, $0
  39         addq    $0, 1, $0
  40         cmoveq  $16, 0, $0
  41
  42         nop
  43         nop
  44         nop
  45         ret
  46
  47 END(__ffs)
  48
  49 weak_alias (__ffs, ffs)
  50 libc_hidden_def (__ffs)
  51 libc_hidden_builtin_def (ffs)