sysdeps/alpha/nptl/pthread_spin_lock.S

   1 /* Copyright (C) 2003-2015 Free Software Foundation, Inc.
   2    This file is part of the GNU C Library.
   3    Contributed by Richard Henderson  <rth@twiddle.net>, 2003.
   4
   5    The GNU C Library is free software; you can redistribute it and/or
   6    modify it under the terms of the GNU Lesser General Public
   7    License as published by the Free Software Foundation; either
   8    version 2.1 of the License, or (at your option) any later version.
   9
  10    The GNU C Library is distributed in the hope that it will be useful,
  11    but WITHOUT ANY WARRANTY; without even the implied warranty of
  12    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
  13    Lesser General Public License for more details.
  14
  15    You should have received a copy of the GNU Lesser General Public
  16    License along with the GNU C Library.  If not, see
  17    <http://www.gnu.org/licenses/>.  */
  18
  19
  20         .text
  21         .align  4
  22
  23         .globl  pthread_spin_lock
  24         .ent    pthread_spin_lock
  25 pthread_spin_lock:
  26         .frame  $sp, 0, $26, 0
  27         .prologue 0
  28
  29 0:      ldl_l   $1, 0($16)
  30         lda     $2, 1
  31         lda     $0, 0
  32         bne     $1, 1f
  33
  34         stl_c   $2, 0($16)
  35         beq     $2, 1f
  36         mb
  37         ret
  38
  39 1:      ldl     $1, 0($16)
  40         bne     $1, 1b
  41         unop
  42         br      0b
  43
  44         .end    pthread_spin_lock