BitsBenchmark.cpp File Reference

#include <algorithm>
#include <vector>
#include <folly/CppAttributes.h>
#include <folly/Random.h>
#include <folly/lang/Assume.h>
#include <folly/lang/Bits.h>
#include <folly/Benchmark.h>

Go to the source code of this file.

Functions
	BENCHMARK (nextPowTwoClz, iters)
	BENCHMARK_DRAW_LINE ()
	BENCHMARK (isPowTwo, iters)
	BENCHMARK (reverse, iters)
	BENCHMARK (PartialLoadUnaligned, iters)
	BENCHMARK (PartialLoadUnalignedMemcpy, iters)
	BENCHMARK (PartialLoadUnalignedSwitch, iters)
int	main (int argc, char **argv)

Function Documentation

BENCHMARK	(	nextPowTwoClz	,
		iters
	)

Definition at line 31 of file BitsBenchmark.cpp.

References folly::BENCHMARK_DRAW_LINE(), folly::doNotOptimizeAway(), i, and folly::nextPowTwo().

                                {
  for (unsigned long i = 0; i < iters; ++i) {
    auto x = folly::nextPowTwo(i);
    folly::doNotOptimizeAway(x);
  }
}

BENCHMARK	(	isPowTwo	,
		iters
	)

Definition at line 39 of file BitsBenchmark.cpp.

References b, folly::BENCHMARK_DRAW_LINE(), folly::doNotOptimizeAway(), i, and folly::isPowTwo().

                           {
  bool b;
  for (unsigned long i = 0; i < iters; ++i) {
    b = folly::isPowTwo(i);
    folly::doNotOptimizeAway(b);
  }
}

BENCHMARK	(	reverse	,
		iters
	)

Definition at line 48 of file BitsBenchmark.cpp.

References folly::assume(), b, folly::BENCHMARK_DRAW_LINE(), BENCHMARK_SUSPEND, folly::bitReverse(), folly::doNotOptimizeAway(), f, FOLLY_FALLTHROUGH, i, folly::Random::rand32(), and uint64_t.

                          {
  uint64_t b = 0;
  for (unsigned long i = 0; i < iters; ++i) {
    b = folly::bitReverse(i + b);
    folly::doNotOptimizeAway(b);
  }
}

BENCHMARK	(	PartialLoadUnaligned	,
		iters
	)

Definition at line 126 of file BitsBenchmark.cpp.

                                       {
  testPartialLoadUnaligned(folly::partialLoadUnaligned<uint64_t>, iters);
}

BENCHMARK	(	PartialLoadUnalignedMemcpy	,
		iters
	)

Definition at line 130 of file BitsBenchmark.cpp.

References folly::assume(), and uint64_t.

                                             {
  testPartialLoadUnaligned(
      [](const char* p, size_t l) {
        folly::assume(l < 8);

        uint64_t ret;
        memcpy(&ret, p, l);
        return ret;
      },
      iters);
}

BENCHMARK	(	PartialLoadUnalignedSwitch	,
		iters
	)

Definition at line 142 of file BitsBenchmark.cpp.

                                             {
  testPartialLoadUnaligned(partialLoadUnalignedSwitch, iters);
}

BENCHMARK_DRAW_LINE

(

)

int main	(	int	argc,
		char **	argv
	)

Definition at line 146 of file BitsBenchmark.cpp.

References folly::runBenchmarks().

                                {
  gflags::ParseCommandLineFlags(&argc, &argv, true);
  folly::runBenchmarks();
  return 0;
}