sysdeps/powerpc/powerpc32/hp-timing.h

   1 /* High precision, low overhead timing functions.  Linux/PPC32 version.
   2    Copyright (C) 2005-2014 Free Software Foundation, Inc.
   3    This file is part of the GNU C Library.
   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 #ifndef _HP_TIMING_H
  20 #define _HP_TIMING_H    1
  21
  22
  23 /* There are no generic definitions for the times.  We could write something
  24    using the `gettimeofday' system call where available but the overhead of
  25    the system call might be too high.
  26
  27    In case a platform supports timers in the hardware the following macros
  28    and types must be defined:
  29
  30    - HP_TIMING_AVAIL: test for availability.
  31
  32    - HP_TIMING_INLINE: this macro is non-zero if the functionality is not
  33      implemented using function calls but instead uses some inlined code
  34      which might simply consist of a few assembler instructions.  We have to
  35      know this since we might want to use the macros here in places where we
  36      cannot make function calls.
  37
  38    - hp_timing_t: This is the type for variables used to store the time
  39      values.
  40
  41    - HP_TIMING_ZERO: clear `hp_timing_t' object.
  42
  43    - HP_TIMING_NOW: place timestamp for current time in variable given as
  44      parameter.
  45
  46    - HP_TIMING_DIFF_INIT: do whatever is necessary to be able to use the
  47      HP_TIMING_DIFF macro.
  48
  49    - HP_TIMING_DIFF: compute difference between two times and store it
  50      in a third.  Source and destination might overlap.
  51
  52    - HP_TIMING_ACCUM: add time difference to another variable.  This might
  53      be a bit more complicated to implement for some platforms as the
  54      operation should be thread-safe and 64bit arithmetic on 32bit platforms
  55      is not.
  56
  57    - HP_TIMING_ACCUM_NT: this is the variant for situations where we know
  58      there are no threads involved.
  59
  60    - HP_TIMING_PRINT: write decimal representation of the timing value into
  61      the given string.  This operation need not be inline even though
  62      HP_TIMING_INLINE is specified.
  63
  64 */
  65
  66 /* Provide dummy definitions.  */
  67 #define HP_TIMING_AVAIL         (0)
  68 #define HP_TIMING_INLINE        (0)
  69 typedef unsigned long long int hp_timing_t;
  70 #define HP_TIMING_ZERO(Var)
  71 #define HP_TIMING_NOW(var)
  72 #define HP_TIMING_DIFF_INIT()
  73 #define HP_TIMING_DIFF(Diff, Start, End)
  74 #define HP_TIMING_ACCUM(Sum, Diff)
  75 #define HP_TIMING_ACCUM_NT(Sum, Diff)
  76 #define HP_TIMING_PRINT(Buf, Len, Val)
  77
  78 /* Since this implementation is not available we tell the user about it.  */
  79 #define HP_TIMING_NONAVAIL      1
  80
  81 #endif /* hp-timing.h */