From 36d3441dc03d1551d48aa424c55905b6c9e5c14d Mon Sep 17 00:00:00 2001 From: Shikhar Date: Thu, 1 Jan 2026 08:09:00 +0530 Subject: [PATCH] add bench_uint16 Signed-off-by: Shikhar --- benchmarks/CMakeLists.txt | 6 ++ benchmarks/bench_uint16.cpp | 139 ++++++++++++++++++++++++++++++++++++ 2 files changed, 145 insertions(+) create mode 100644 benchmarks/bench_uint16.cpp diff --git a/benchmarks/CMakeLists.txt b/benchmarks/CMakeLists.txt index 4ee5789..81ea92a 100644 --- a/benchmarks/CMakeLists.txt +++ b/benchmarks/CMakeLists.txt @@ -11,7 +11,9 @@ FetchContent_MakeAvailable(counters) add_executable(realbenchmark benchmark.cpp) target_link_libraries(realbenchmark PRIVATE counters::counters) add_executable(bench_ip bench_ip.cpp) +add_executable(bench_uint16 bench_uint16.cpp) target_link_libraries(bench_ip PRIVATE counters::counters) +target_link_libraries(bench_uint16 PRIVATE counters::counters) set_property( TARGET realbenchmark @@ -19,8 +21,12 @@ set_property( set_property( TARGET bench_ip PROPERTY CXX_STANDARD 17) +set_property( + TARGET bench_uint16 + PROPERTY CXX_STANDARD 17) target_link_libraries(realbenchmark PUBLIC fast_float) target_link_libraries(bench_ip PUBLIC fast_float) +target_link_libraries(bench_uint16 PUBLIC fast_float) include(ExternalProject) diff --git a/benchmarks/bench_uint16.cpp b/benchmarks/bench_uint16.cpp new file mode 100644 index 0000000..c4cef81 --- /dev/null +++ b/benchmarks/bench_uint16.cpp @@ -0,0 +1,139 @@ +#include "counters/bench.h" +#include "fast_float/fast_float.h" +#include +#include +#include +#include +#include +#include +#include +#include +#include + +void pretty_print(size_t volume, size_t bytes, std::string name, + counters::event_aggregate agg) { + if (agg.inner_count > 1) { + printf("# (inner count: %d)\n", agg.inner_count); + } + printf("%-40s : ", name.c_str()); + printf(" %5.2f GB/s ", bytes / agg.fastest_elapsed_ns()); + printf(" %5.1f Mip/s ", volume * 1000.0 / agg.fastest_elapsed_ns()); + printf(" %5.2f ns/ip ", agg.fastest_elapsed_ns() / volume); + if (counters::event_collector().has_events()) { + printf(" %5.2f GHz ", agg.fastest_cycles() / agg.fastest_elapsed_ns()); + printf(" %5.2f c/ip ", agg.fastest_cycles() / volume); + printf(" %5.2f i/ip ", agg.fastest_instructions() / volume); + printf(" %5.2f c/b ", agg.fastest_cycles() / bytes); + printf(" %5.2f i/b ", agg.fastest_instructions() / bytes); + printf(" %5.2f i/c ", agg.fastest_instructions() / agg.fastest_cycles()); + } + printf("\n"); +} + +enum class parse_method { standard, fast_float }; + +void validate(const std::string &buffer, const std::vector &expected, + char delimiter) { + const char *p = buffer.data(); + const char *pend = p + buffer.size(); + + for (size_t i = 0; i < expected.size(); i++) { + uint16_t val; + auto r = fast_float::from_chars(p, pend, val); + if (r.ec != std::errc() || val != expected[i]) { + printf("Validation failed at index %zu: expected %u, got %u\n", i, + expected[i], val); + std::abort(); + } + p = r.ptr; + if (i + 1 < expected.size()) { + if (p >= pend || *p != delimiter) { + printf("Validation failed at index %zu: delimiter mismatch\n", i); + std::abort(); + } + ++p; + } + } + + if (p != pend) { + printf("Validation failed: trailing bytes remain\n"); + std::abort(); + } + printf("Validation passed!\n"); +} + +int main() { + constexpr size_t N = 500000; + constexpr char delimiter = ','; + std::mt19937 rng(1234); + std::uniform_int_distribution dist(0, 65535); + + std::vector expected; + expected.reserve(N); + + std::string buffer; + buffer.reserve(N * 6); // up to 5 digits + delimiter + + for (size_t i = 0; i < N; ++i) { + uint16_t val = (uint16_t)dist(rng); + expected.push_back(val); + std::string s = std::to_string(val); + buffer.append(s); + if (i + 1 < N) { + buffer.push_back(delimiter); + } + } + + size_t total_bytes = buffer.size(); + + validate(buffer, expected, delimiter); + + volatile uint64_t sink = 0; + + pretty_print(N, total_bytes, "parse_uint16_std_fromchars", + counters::bench([&]() { + uint64_t sum = 0; + const char *p = buffer.data(); + const char *pend = p + buffer.size(); + for (size_t i = 0; i < N; ++i) { + uint16_t value = 0; + auto r = std::from_chars(p, pend, value); + if (r.ec != std::errc()) + std::abort(); + sum += value; + p = r.ptr; + if (i + 1 < N) { + if (p >= pend || *p != delimiter) + std::abort(); + ++p; + } + } + if (p != pend) + std::abort(); + sink += sum; + })); + + pretty_print(N, total_bytes, "parse_uint16_fastfloat", counters::bench([&]() { + uint64_t sum = 0; + const char *p = buffer.data(); + const char *pend = p + buffer.size(); + for (size_t i = 0; i < N; ++i) { + uint16_t value = 0; + auto r = fast_float::from_chars(p, pend, value); + if (r.ec != std::errc()) + std::abort(); + sum += value; + p = r.ptr; + if (i + 1 < N) { + if (p >= pend || *p != delimiter) + std::abort(); + ++p; + } + } + if (p != pend) + std::abort(); + sink += sum; + })); + + return EXIT_SUCCESS; +}