/* High precision, low overhead timing functions. Generic version. Copyright (C) 1998, 2000 Free Software Foundation, Inc. This file is part of the GNU C Library. Contributed by Ulrich Drepper <drepper@cygnus.com>, 1998. The GNU C Library is free software; you can redistribute it and/or modify it under the terms of the GNU Lesser General Public License as published by the Free Software Foundation; either version 2.1 of the License, or (at your option) any later version. The GNU C Library is distributed in the hope that it will be useful, but WITHOUT ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU Lesser General Public License for more details. You should have received a copy of the GNU Lesser General Public License along with the GNU C Library; if not, see <http://www.gnu.org/licenses/>. */ #ifndef _HP_TIMING_H #define _HP_TIMING_H 1 /* There are no generic definitions for the times. We could write something using the `gettimeofday' system call where available but the overhead of the system call might be too high. In case a platform supports timers in the hardware the following macros and types must be defined: - HP_TIMING_AVAIL: test for availability. - HP_TIMING_INLINE: this macro is non-zero if the functionality is not implemented using function calls but instead uses some inlined code which might simply consist of a few assembler instructions. We have to know this since we might want to use the macros here in places where we cannot make function calls. - hp_timing_t: This is the type for variables used to store the time values. - HP_TIMING_ZERO: clear `hp_timing_t' object. - HP_TIMING_NOW: place timestamp for current time in variable given as parameter. - HP_TIMING_DIFF_INIT: do whatever is necessary to be able to use the HP_TIMING_DIFF macro. - HP_TIMING_DIFF: compute difference between two times and store it in a third. Source and destination might overlap. - HP_TIMING_ACCUM: add time difference to another variable. This might be a bit more complicated to implement for some platforms as the operation should be thread-safe and 64bit arithmetic on 32bit platforms is not. - HP_TIMING_ACCUM_NT: this is the variant for situations where we know there are no threads involved. - HP_TIMING_PRINT: write decimal representation of the timing value into the given string. This operation need not be inline even though HP_TIMING_INLINE is specified. */ /* Provide dummy definitions. */ #define HP_TIMING_AVAIL (0) #define HP_TIMING_INLINE (0) typedef int hp_timing_t; #define HP_TIMING_ZERO(Var) #define HP_TIMING_NOW(var) #define HP_TIMING_DIFF_INIT() #define HP_TIMING_DIFF(Diff, Start, End) #define HP_TIMING_ACCUM(Sum, Diff) #define HP_TIMING_ACCUM_NT(Sum, Diff) #define HP_TIMING_PRINT(Buf, Len, Val) /* Since this implementation is not available we tell the user about it. */ #define HP_TIMING_NONAVAIL 1 #endif /* hp-timing.h */