diff options
| -rw-r--r-- | src/Makefile.bench.include | 1 | ||||
| -rw-r--r-- | src/bench/strencodings.cpp | 18 | ||||
| -rw-r--r-- | src/test/util_tests.cpp | 18 | ||||
| -rw-r--r-- | src/util/strencodings.cpp | 33 |
4 files changed, 64 insertions, 6 deletions
diff --git a/src/Makefile.bench.include b/src/Makefile.bench.include index e90c8530d8..532f668668 100644 --- a/src/Makefile.bench.include +++ b/src/Makefile.bench.include @@ -44,6 +44,7 @@ bench_bench_bitcoin_SOURCES = \ bench/rollingbloom.cpp \ bench/rpc_blockchain.cpp \ bench/rpc_mempool.cpp \ + bench/strencodings.cpp \ bench/util_time.cpp \ bench/verify_script.cpp diff --git a/src/bench/strencodings.cpp b/src/bench/strencodings.cpp new file mode 100644 index 0000000000..69b3a83cbf --- /dev/null +++ b/src/bench/strencodings.cpp @@ -0,0 +1,18 @@ +// Copyright (c) 2022 The Bitcoin Core developers +// Distributed under the MIT software license, see the accompanying +// file COPYING or http://www.opensource.org/licenses/mit-license.php. + +#include <bench/bench.h> +#include <bench/data.h> +#include <util/strencodings.h> + +static void HexStrBench(benchmark::Bench& bench) +{ + auto const& data = benchmark::data::block413567; + bench.batch(data.size()).unit("byte").run([&] { + auto hex = HexStr(data); + ankerl::nanobench::doNotOptimizeAway(hex); + }); +} + +BENCHMARK(HexStrBench); diff --git a/src/test/util_tests.cpp b/src/test/util_tests.cpp index 890b2f997e..3b2aca5887 100644 --- a/src/test/util_tests.cpp +++ b/src/test/util_tests.cpp @@ -198,6 +198,24 @@ BOOST_AUTO_TEST_CASE(util_HexStr) BOOST_CHECK_EQUAL(HexStr(in_s), out_exp); BOOST_CHECK_EQUAL(HexStr(in_b), out_exp); } + + { + auto input = std::string(); + for (size_t i=0; i<256; ++i) { + input.push_back(static_cast<char>(i)); + } + + auto hex = HexStr(input); + BOOST_TEST_REQUIRE(hex.size() == 512); + static constexpr auto hexmap = std::string_view("0123456789abcdef"); + for (size_t i = 0; i < 256; ++i) { + auto upper = hexmap.find(hex[i * 2]); + auto lower = hexmap.find(hex[i * 2 + 1]); + BOOST_TEST_REQUIRE(upper != std::string_view::npos); + BOOST_TEST_REQUIRE(lower != std::string_view::npos); + BOOST_TEST_REQUIRE(i == upper*16 + lower); + } + } } BOOST_AUTO_TEST_CASE(span_write_bytes) diff --git a/src/util/strencodings.cpp b/src/util/strencodings.cpp index 35f62f0422..bcedd4f517 100644 --- a/src/util/strencodings.cpp +++ b/src/util/strencodings.cpp @@ -9,6 +9,7 @@ #include <tinyformat.h> #include <algorithm> +#include <array> #include <cstdlib> #include <cstring> #include <limits> @@ -452,17 +453,37 @@ std::string Capitalize(std::string str) return str; } +namespace { + +using ByteAsHex = std::array<char, 2>; + +constexpr std::array<ByteAsHex, 256> CreateByteToHexMap() +{ + constexpr char hexmap[16] = {'0', '1', '2', '3', '4', '5', '6', '7', '8', '9', 'a', 'b', 'c', 'd', 'e', 'f'}; + + std::array<ByteAsHex, 256> byte_to_hex{}; + for (size_t i = 0; i < byte_to_hex.size(); ++i) { + byte_to_hex[i][0] = hexmap[i >> 4]; + byte_to_hex[i][1] = hexmap[i & 15]; + } + return byte_to_hex; +} + +} // namespace + std::string HexStr(const Span<const uint8_t> s) { std::string rv(s.size() * 2, '\0'); - static constexpr char hexmap[16] = { '0', '1', '2', '3', '4', '5', '6', '7', - '8', '9', 'a', 'b', 'c', 'd', 'e', 'f' }; - auto it = rv.begin(); + static constexpr auto byte_to_hex = CreateByteToHexMap(); + static_assert(sizeof(byte_to_hex) == 512); + + char* it = rv.data(); for (uint8_t v : s) { - *it++ = hexmap[v >> 4]; - *it++ = hexmap[v & 15]; + std::memcpy(it, byte_to_hex[v].data(), 2); + it += 2; } - assert(it == rv.end()); + + assert(it == rv.data() + rv.size()); return rv; } |