#include <iostream>
#include <vector>
#include <OpenImageIO/function_view.h>
#include <OpenImageIO/string_view.h>
#include <OpenImageIO/strutil.h>
#include <OpenImageIO/timer.h>

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Classes
class	Benchmarker

Namespaces
	pvt

Functions
template<class T >
OIIO_NAMESPACE_BEGIN OIIO_FORCEINLINE T const &	DoNotOptimize (T const &val)

OIIO_FORCEINLINE void	clobber_all_memory ()

void OIIO_UTIL_API	clobber (void *p)

OIIO_FORCEINLINE void	clobber (const void *p)

template<typename T >
OIIO_FORCEINLINE T &	clobber (T &p)

template<typename T , typename... Ts>
OIIO_FORCEINLINE void	clobber (T &p, Ts &...ps)

template<typename FUNC >
double	time_trial (FUNC func, int ntrials=1, int nrepeats=1, double *range=NULL)

template<typename FUNC >
double	time_trial (FUNC func, int ntrials, double *range)
	Version without repeats. More...

OIIO_UTIL_API std::vector< double >	timed_thread_wedge (function_view< void(int)> task, function_view< void()> pretask, function_view< void()> posttask, std::ostream *out, int maxthreads, int total_iterations, int ntrials, cspan< int > threadcounts={1, 2, 4, 8, 12, 16, 24, 32, 48, 64, 128})

OIIO_UTIL_API void	timed_thread_wedge (function_view< void(int)> task, int maxthreads, int total_iterations, int ntrials, cspan< int > threadcounts={1, 2, 4, 8, 12, 16, 24, 32, 48, 64, 128})

void OIIO_UTIL_API	pvt::use_char_ptr (char const volatile *)

template<class T >
OIIO_FORCEINLINE T const &	DoNotOptimize (T const &val)

Function Documentation

void OIIO_UTIL_API clobber ( void * p )

A call to clobber(p) fools the compiler into thinking that p (or *p, for the pointer version) might potentially have its memory altered. The implementation actually does nothing, but it's in another module, so the compiler won't know this and will be conservative about any assumptions of what's in p. This is helpful for benchmarking, to help erase any preconceptions the optimizer has about what might be in a variable.

OIIO_FORCEINLINE void clobber ( const void * p )

Definition at line 49 of file benchmark.h.

template<typename T >

OIIO_FORCEINLINE T& clobber ( T & p )

Definition at line 52 of file benchmark.h.

template<typename T , typename... Ts>

OIIO_FORCEINLINE void clobber	(	T &	p,
		Ts &...	ps
	)

Definition at line 56 of file benchmark.h.

OIIO_FORCEINLINE void clobber_all_memory ( )

clobber_all_memory() is a helper function for timing benchmarks that fools the compiler into thinking that potentially any part of memory has been modified, and thus serves as a barrier where the optimizer won't assume anything about the state of memory preceding it.

Definition at line 465 of file benchmark.h.

template<class T >

OIIO_NAMESPACE_BEGIN OIIO_FORCEINLINE T const& DoNotOptimize ( T const & val )

DoNotOptimize(val) is a helper function for timing benchmarks that fools the compiler into thinking the the location 'val' is used and will not optimize it away. For benchmarks only, do not use in production code! May not work on all platforms. References:

Chandler Carruth's CppCon 2015 talk
Folly https://github.com/facebook/folly/blob/master/folly/Benchmark.h
Google Benchmark https://github.com/google/benchmark/blob/master/include/benchmark/benchmark_api.h

Definition at line 440 of file benchmark.h.

template<class T >

OIIO_FORCEINLINE T const& DoNotOptimize ( T const & val )

DoNotOptimize(val) is a helper function for timing benchmarks that fools the compiler into thinking the the location 'val' is used and will not optimize it away. For benchmarks only, do not use in production code! May not work on all platforms. References:

Chandler Carruth's CppCon 2015 talk
Folly https://github.com/facebook/folly/blob/master/folly/Benchmark.h
Google Benchmark https://github.com/google/benchmark/blob/master/include/benchmark/benchmark_api.h

Definition at line 440 of file benchmark.h.

template<typename FUNC >

double time_trial	(	FUNC	func,
		int	ntrials = `1`,
		int	nrepeats = `1`,
		double *	range = `NULL`
	)

Helper template that runs a function (or functor) n times, using a Timer to benchmark the results, and returning the fastest trial. If 'range' is non-NULL, the range (max-min) of the various time trials will be stored there.

DEPRECATED(1.8): This may be considered obsolete, probably the Benchmarker class is a better solution.

Definition at line 313 of file benchmark.h.

template<typename FUNC >

double time_trial	(	FUNC	func,
		int	ntrials,
		double *	range
	)

Version without repeats.

Definition at line 337 of file benchmark.h.

OIIO_UTIL_API std::vector<double> timed_thread_wedge	(	function_view< void(int)>	task,
		function_view< void()>	pretask,
		function_view< void()>	posttask,
		std::ostream *	out,
		int	maxthreads,
		int	total_iterations,
		int	ntrials,
		cspan< int >	threadcounts = `{1, 2, 4, 8, 12, 16, 24, 32, 48, 64, 128}`
	)

OIIO_UTIL_API void timed_thread_wedge	(	function_view< void(int)>	task,
		int	maxthreads,
		int	total_iterations,
		int	ntrials,
		cspan< int >	threadcounts = `{1, 2, 4, 8, 12, 16, 24, 32, 48, 64, 128}`
	)

Classes

Namespaces

Functions

Function Documentation