contrib/benchmarks/MatrixFunctions/bench_matrix_power.cpp

// Benchmarks for matrix power functions: sqrt, pow, cos, sin, cosh, sinh.
// SPDX-FileCopyrightText: The Eigen Authors
// SPDX-License-Identifier: MPL-2.0

#include <benchmark/benchmark.h>
#include <Eigen/Core>
#include <contrib/Eigen/MatrixFunctions>

using namespace Eigen;

typedef double Scalar;
typedef Matrix<Scalar, Dynamic, Dynamic> Mat;

static void BM_MatrixSqrt(benchmark::State& state) {
  int n = state.range(0);
  // SPD matrix has well-defined sqrt.
  Mat tmp = Mat::Random(n, n);
  Mat A = tmp * tmp.transpose() + Mat::Identity(n, n);
  Mat result(n, n);

  for (auto _ : state) {
    result = A.sqrt();
    benchmark::DoNotOptimize(result.data());
    benchmark::ClobberMemory();
  }
}

static void BM_MatrixPow(benchmark::State& state) {
  int n = state.range(0);
  Mat tmp = Mat::Random(n, n);
  Mat A = tmp * tmp.transpose() + Mat::Identity(n, n);
  Mat result(n, n);
  Scalar p = 2.5;

  for (auto _ : state) {
    result = A.pow(p);
    benchmark::DoNotOptimize(result.data());
    benchmark::ClobberMemory();
  }
}

static void BM_MatrixCos(benchmark::State& state) {
  int n = state.range(0);
  Mat A = Mat::Random(n, n) / Scalar(n);
  Mat result(n, n);

  for (auto _ : state) {
    result = A.cos();
    benchmark::DoNotOptimize(result.data());
    benchmark::ClobberMemory();
  }
}

static void BM_MatrixSin(benchmark::State& state) {
  int n = state.range(0);
  Mat A = Mat::Random(n, n) / Scalar(n);
  Mat result(n, n);

  for (auto _ : state) {
    result = A.sin();
    benchmark::DoNotOptimize(result.data());
    benchmark::ClobberMemory();
  }
}

static void BM_MatrixCosh(benchmark::State& state) {
  int n = state.range(0);
  Mat A = Mat::Random(n, n) / Scalar(n);
  Mat result(n, n);

  for (auto _ : state) {
    result = A.cosh();
    benchmark::DoNotOptimize(result.data());
    benchmark::ClobberMemory();
  }
}

static void BM_MatrixSinh(benchmark::State& state) {
  int n = state.range(0);
  Mat A = Mat::Random(n, n) / Scalar(n);
  Mat result(n, n);

  for (auto _ : state) {
    result = A.sinh();
    benchmark::DoNotOptimize(result.data());
    benchmark::ClobberMemory();
  }
}

#define MAT_POWER_SIZES ->Arg(4)->Arg(8)->Arg(16)->Arg(32)->Arg(64)

BENCHMARK(BM_MatrixSqrt) MAT_POWER_SIZES;
BENCHMARK(BM_MatrixPow) MAT_POWER_SIZES;
BENCHMARK(BM_MatrixCos) MAT_POWER_SIZES;
BENCHMARK(BM_MatrixSin) MAT_POWER_SIZES;
BENCHMARK(BM_MatrixCosh) MAT_POWER_SIZES;
BENCHMARK(BM_MatrixSinh) MAT_POWER_SIZES;