Abseil Common Libraries (C++) (grcp 依赖)
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61 lines
2.0 KiB
61 lines
2.0 KiB
// Copyright 2017 The Abseil Authors. |
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// |
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// Licensed under the Apache License, Version 2.0 (the "License"); |
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// you may not use this file except in compliance with the License. |
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// You may obtain a copy of the License at |
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// |
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// http://www.apache.org/licenses/LICENSE-2.0 |
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// |
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// Unless required by applicable law or agreed to in writing, software |
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// distributed under the License is distributed on an "AS IS" BASIS, |
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// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. |
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// See the License for the specific language governing permissions and |
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// limitations under the License. |
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#include "absl/strings/internal/char_map.h" |
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#include <cstdint> |
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#include "benchmark/benchmark.h" |
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namespace { |
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absl::strings_internal::Charmap MakeBenchmarkMap() { |
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absl::strings_internal::Charmap m; |
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uint32_t x[] = {0x0, 0x1, 0x2, 0x3, 0xf, 0xe, 0xd, 0xc}; |
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for (uint32_t& t : x) t *= static_cast<uint32_t>(0x11111111UL); |
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for (uint32_t i = 0; i < 256; ++i) { |
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if ((x[i / 32] >> (i % 32)) & 1) |
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m = m | absl::strings_internal::Charmap::Char(i); |
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} |
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return m; |
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} |
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// Micro-benchmark for Charmap::contains. |
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void BM_Contains(benchmark::State& state) { |
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// Loop-body replicated 10 times to increase time per iteration. |
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// Argument continuously changed to avoid generating common subexpressions. |
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const absl::strings_internal::Charmap benchmark_map = MakeBenchmarkMap(); |
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unsigned char c = 0; |
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int ops = 0; |
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for (auto _ : state) { |
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ops += benchmark_map.contains(c++); |
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ops += benchmark_map.contains(c++); |
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ops += benchmark_map.contains(c++); |
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ops += benchmark_map.contains(c++); |
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ops += benchmark_map.contains(c++); |
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ops += benchmark_map.contains(c++); |
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ops += benchmark_map.contains(c++); |
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ops += benchmark_map.contains(c++); |
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ops += benchmark_map.contains(c++); |
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ops += benchmark_map.contains(c++); |
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} |
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benchmark::DoNotOptimize(ops); |
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} |
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BENCHMARK(BM_Contains); |
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// We don't bother benchmarking Charmap::IsZero or Charmap::IntersectsWith; |
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// their running time is data-dependent and it is not worth characterizing |
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// "typical" data. |
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} // namespace
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