src/utils.h

   1 /* Guile-R6RS-Libs --- Implementation of R6RS standard libraries.
   2    Copyright (C) 2007, 2009  Ludovic Courtès <ludo@gnu.org>
   3
   4    Guile-R6RS-Libs 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    Guile-R6RS-Libs 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 Guile-R6RS-Libs; if not, write to the Free Software
  16    Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA  02110-1301  USA  */
  17
  18 #ifndef GUILE_R6RS_UTILS_H
  19 #define GUILE_R6RS_UTILS_H
  20
  21 /* Common utilities.  */
  22
  23 /* `SCM_LIKELY ()' and `SCM_UNLIKELY ()' appeared sometime during the Guile
  24    1.8 release series.  */
  25
  26 #ifndef SCM_LIKELY
  27 # ifdef __GNUC__
  28 #  define SCM_LIKELY(_cond)    (__builtin_expect (!!(_cond), 1))
  29 #  define SCM_UNLIKELY(_cond)  (__builtin_expect ((_cond), 0))
  30 # else
  31 #  define SCM_LIKELY(_cond)    (_cond)
  32 #  define SCM_UNLIKELY(_cond)  (_cond)
  33 # endif
  34 #endif
  35
  36 #endif
  37
  38 /* arch-tag: 878d0655-2504-4154-bf27-fab06652ebd5
  39  */