File: hash.bench.cpp

package info (click to toggle)
llvm-toolchain-20 1%3A20.1.6-1~exp1
  • links: PTS, VCS
  • area: main
  • in suites: experimental
  • size: 2,111,304 kB
  • sloc: cpp: 7,438,677; ansic: 1,393,822; asm: 1,012,926; python: 241,650; f90: 86,635; objc: 75,479; lisp: 42,144; pascal: 17,286; sh: 10,027; ml: 5,082; perl: 4,730; awk: 3,523; makefile: 3,349; javascript: 2,251; xml: 892; fortran: 672
file content (42 lines) | stat: -rw-r--r-- 1,321 bytes parent folder | download | duplicates (2)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
//===----------------------------------------------------------------------===//
//
// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
// See https://llvm.org/LICENSE.txt for license information.
// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
//
//===----------------------------------------------------------------------===//

// UNSUPPORTED: c++03

#include <cstdint>
#include <cstddef>
#include <functional>

#include "benchmark/benchmark.h"

#include "GenerateInput.h"
#include "test_macros.h"

constexpr std::size_t TestNumInputs = 1024;

template <class HashFn, class GenInputs>
void BM_Hash(benchmark::State& st, HashFn fn, GenInputs gen) {
  auto in               = gen(st.range(0));
  const auto end        = in.data() + in.size();
  std::size_t last_hash = 0;
  benchmark::DoNotOptimize(&last_hash);
  while (st.KeepRunning()) {
    for (auto it = in.data(); it != end; ++it) {
      benchmark::DoNotOptimize(last_hash += fn(*it));
    }
    benchmark::ClobberMemory();
  }
}

BENCHMARK_CAPTURE(BM_Hash, uint32_random_std_hash, std::hash<uint32_t>{}, getRandomIntegerInputs<uint32_t>)
    ->Arg(TestNumInputs);

BENCHMARK_CAPTURE(BM_Hash, uint32_top_std_hash, std::hash<uint32_t>{}, getSortedTopBitsIntegerInputs<uint32_t>)
    ->Arg(TestNumInputs);

BENCHMARK_MAIN();