toss_me.hpp

#ifndef CALLBACK_TOSS_ME_HPP
#define CALLBACK_TOSS_ME_HPP

#include <benchmark/benchmark.h>
#include <stan/math.hpp>
#include <utility>

static bool needs_done = true;
// Just to fill up the stack allocator
template <int max_alloc>
static void toss_me(benchmark::State& state) {
  using stan::math::var;
  if (needs_done) {
    needs_done = false;
    using stan::math::var;
    using stan::math::sum;
    Eigen::Matrix<var, -1, -1> x(Eigen::MatrixXd::Random(max_alloc, max_alloc));
    Eigen::Matrix<var, -1, -1> y(Eigen::MatrixXd::Random(max_alloc, max_alloc));
    Eigen::Matrix<var, -1, -1> z = elt_multiply(x, y);
    var lp = sum(z);
    benchmark::DoNotOptimize(lp.vi_);
    for (auto _ : state) {
      lp.grad();
      stan::math::set_zero_all_adjoints();
    }
    stan::math::recover_memory();
  }
}

#endif