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			83 lines
		
	
	
		
			3.0 KiB
		
	
	
	
		
			C
		
	
	
	
	
	
			
		
		
	
	
			83 lines
		
	
	
		
			3.0 KiB
		
	
	
	
		
			C
		
	
	
	
	
	
| /* High precision, low overhead timing functions.  Generic version.
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|    Copyright (C) 1998-2014 Free Software Foundation, Inc.
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|    This file is part of the GNU C Library.
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|    Contributed by Ulrich Drepper <drepper@cygnus.com>, 1998.
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| 
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|    The GNU C Library is free software; you can redistribute it and/or
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|    modify it under the terms of the GNU Lesser General Public
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|    License as published by the Free Software Foundation; either
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|    version 2.1 of the License, or (at your option) any later version.
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| 
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|    The GNU C Library is distributed in the hope that it will be useful,
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|    but WITHOUT ANY WARRANTY; without even the implied warranty of
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|    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
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|    Lesser General Public License for more details.
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| 
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|    You should have received a copy of the GNU Lesser General Public
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|    License along with the GNU C Library; if not, see
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|    <http://www.gnu.org/licenses/>.  */
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| 
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| #ifndef _HP_TIMING_H
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| #define _HP_TIMING_H	1
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| 
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| 
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| /* There are no generic definitions for the times.  We could write something
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|    using the `gettimeofday' system call where available but the overhead of
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|    the system call might be too high.
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| 
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|    In case a platform supports timers in the hardware the following macros
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|    and types must be defined:
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| 
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|    - HP_TIMING_AVAIL: test for availability.
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| 
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|    - HP_TIMING_INLINE: this macro is non-zero if the functionality is not
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|      implemented using function calls but instead uses some inlined code
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|      which might simply consist of a few assembler instructions.  We have to
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|      know this since we might want to use the macros here in places where we
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|      cannot make function calls.
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| 
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|    - hp_timing_t: This is the type for variables used to store the time
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|      values.
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| 
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|    - HP_TIMING_ZERO: clear `hp_timing_t' object.
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| 
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|    - HP_TIMING_NOW: place timestamp for current time in variable given as
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|      parameter.
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| 
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|    - HP_TIMING_DIFF_INIT: do whatever is necessary to be able to use the
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|      HP_TIMING_DIFF macro.
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| 
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|    - HP_TIMING_DIFF: compute difference between two times and store it
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|      in a third.  Source and destination might overlap.
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| 
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|    - HP_TIMING_ACCUM: add time difference to another variable.  This might
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|      be a bit more complicated to implement for some platforms as the
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|      operation should be thread-safe and 64bit arithmetic on 32bit platforms
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|      is not.
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| 
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|    - HP_TIMING_ACCUM_NT: this is the variant for situations where we know
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|      there are no threads involved.
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| 
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|    - HP_TIMING_PRINT: write decimal representation of the timing value into
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|      the given string.  This operation need not be inline even though
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|      HP_TIMING_INLINE is specified.
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| 
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| */
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| 
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| /* Provide dummy definitions.  */
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| #define HP_TIMING_AVAIL		(0)
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| #define HP_TIMING_INLINE	(0)
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| typedef int hp_timing_t;
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| #define HP_TIMING_ZERO(Var)
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| #define HP_TIMING_NOW(var)
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| #define HP_TIMING_DIFF_INIT()
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| #define HP_TIMING_DIFF(Diff, Start, End)
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| #define HP_TIMING_ACCUM(Sum, Diff)
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| #define HP_TIMING_ACCUM_NT(Sum, Diff)
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| #define HP_TIMING_PRINT(Buf, Len, Val)
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| 
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| /* Since this implementation is not available we tell the user about it.  */
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| #define HP_TIMING_NONAVAIL	1
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| 
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| #endif	/* hp-timing.h */
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