pthread_spin_trylock.S 1.2 KB

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  1. /* Copyright (C) 2002, 2003 Free Software Foundation, Inc.
  2. This file is part of the GNU C Library.
  3. Contributed by Ulrich Drepper <drepper@redhat.com>, 2002.
  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. The GNU C Library is distributed in the hope that it will be useful,
  9. but WITHOUT ANY WARRANTY; without even the implied warranty of
  10. MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
  11. Lesser General Public License for more details.
  12. You should have received a copy of the GNU Lesser General Public
  13. License along with the GNU C Library; if not, see
  14. <http://www.gnu.org/licenses/>. */
  15. #include <pthread-errnos.h>
  16. #ifdef UP
  17. # define LOCK
  18. #else
  19. # define LOCK lock
  20. #endif
  21. .globl pthread_spin_trylock
  22. .type pthread_spin_trylock,@function
  23. .align 16
  24. pthread_spin_trylock:
  25. movl $1, %eax
  26. xorl %ecx, %ecx
  27. LOCK
  28. cmpxchgl %ecx, (%rdi)
  29. movl $EBUSY, %eax
  30. cmovel %ecx, %eax
  31. retq
  32. .size pthread_spin_trylock,.-pthread_spin_trylock