Mercurial > lbo > hg > ccplay
changeset 1:ec6009463e1c
Timing infrastructure, cmake build
| author | Lewin Bormann <lbo@spheniscida.de> |
|---|---|
| date | Sun, 05 Mar 2023 10:01:51 +0100 |
| parents | 85a51415f042 |
| children | ed80bcd28852 |
| files | .clangd .hgignore CMakeLists.txt arrays.cc lib/CMakeLists.txt lib/exec.cc lib/exec.h time.cc |
| diffstat | 8 files changed, 153 insertions(+), 0 deletions(-) [+] |
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--- /dev/null Thu Jan 01 00:00:00 1970 +0000 +++ b/.clangd Sun Mar 05 10:01:51 2023 +0100 @@ -0,0 +1,2 @@ +CompileFlags: + Add: [-std=c++20]
--- /dev/null Thu Jan 01 00:00:00 1970 +0000 +++ b/.hgignore Sun Mar 05 10:01:51 2023 +0100 @@ -0,0 +1,1 @@ +build
--- /dev/null Thu Jan 01 00:00:00 1970 +0000 +++ b/CMakeLists.txt Sun Mar 05 10:01:51 2023 +0100 @@ -0,0 +1,11 @@ +cmake_minimum_required(VERSION 3.26) +project(ccplay) + +ADD_SUBDIRECTORY(lib) + +SET(CMAKE_CXX_FLAGS "${CMAKE_CXX_FLAGS} -std=c++20 -Wall -O") +ADD_EXECUTABLE(time time.cc) +TARGET_LINK_LIBRARIES(time exec) + +ADD_EXECUTABLE(arrays arrays.cc) +TARGET_LINK_LIBRARIES(arrays exec)
--- /dev/null Thu Jan 01 00:00:00 1970 +0000 +++ b/arrays.cc Sun Mar 05 10:01:51 2023 +0100 @@ -0,0 +1,64 @@ +#include <iostream> +#include <vector> +#include <unordered_set> +#include <tuple> +#include "lib/exec.h" + +using namespace std; + +template<typename T> +vector<pair<T,T>> twosum(const vector<T>& v, T sum) { + unordered_set<T> rem; + vector<pair<T,T>> pairs; + for (const T& e : v) { + if (rem.count(sum-e) > 0) { + pairs.push_back(make_pair(e, sum-e)); + } else { + rem.insert(e); + } + } + return pairs; +} + +template<typename T> +void threesum(const vector<T>& v, T sum) { + vector<tuple<T,T,T>> triples; + for (const T& e : v) { + T rem = sum - e; + auto pairs = twosum(v, rem); + for (const pair<T,T>& p : pairs) { + triples.push_back(make_tuple(p.first, p.second, e)); + } + } + /* + for (const auto& t : triples) { + cout << get<0>(t) << " " << get<1>(t) << " " << get<2>(t) << endl; + } + */ +} + +int twosum_entry(void) { + vector<int> v{1,2,3,4,5,6,7,8,9,10,11,12,13,14,15,16,17,18,19,20,-1,-2,-3,-4,-5,-6,-7,-8,-9}; + benchmarkit([&v]() { twosum(v, 20); }); + return 0; +} +int threesum_entry(void) { + vector<int> v{1,2,3,4,5,6,7,8,9,10,11,12,13,14,15,16,17,18,19,20,-1,-2,-3,-4,-5,-6,-7,-8,-9}; + benchmarkit([&v]() { threesum(v, 20); }); + return 0; +} + +int main(int argc, char** argv) { + if (argc < 1) { + cerr << "need task supplied on command line!\n"; + return 1; + } + string task(argv[1]); + + if (task == "twosum") + twosum_entry(); + else if (task == "threesum") + threesum_entry(); + + return 0; +}
--- /dev/null Thu Jan 01 00:00:00 1970 +0000 +++ b/lib/CMakeLists.txt Sun Mar 05 10:01:51 2023 +0100 @@ -0,0 +1,5 @@ + +cmake_minimum_required(VERSION 3.26) + +ADD_LIBRARY(exec exec.cc) +
--- /dev/null Thu Jan 01 00:00:00 1970 +0000 +++ b/lib/exec.cc Sun Mar 05 10:01:51 2023 +0100 @@ -0,0 +1,50 @@ + +#include "exec.h" + +#include <chrono> +#include <iostream> + +using namespace std; +using namespace std::chrono; + +void timeit(function<void()> f, string name) { + auto begin = high_resolution_clock::now(); + + f(); + + auto after = high_resolution_clock::now(); + + auto d = after - begin; + decltype(d)::rep count = d.count(); + decltype(d)::period p; + + cout << name << " :: " << static_cast<double>(p.num)/p.den * count << endl; +} + +void benchmarkit(function<void()> f, string name, function<void()> setup) { + + int n = 1; + const double min_duration = 0.1; + + while (true) { + setup(); + + cout << "Running " << name << " for " << n << " iterations.\n"; + + auto begin = high_resolution_clock::now(); + + for (unsigned int i = 0; i < n; i += 1) + f(); + + auto end = high_resolution_clock::now(); + decltype(end-begin)::period p; + auto seconds = (end-begin).count() * static_cast<double>(p.num)/p.den; + if (seconds < min_duration) { + n *= 2; + } else { + cout << n << " iterations took " << seconds << " seconds (" << seconds/n << " s/iter)\n"; + break; + } + } +} +
--- /dev/null Thu Jan 01 00:00:00 1970 +0000 +++ b/lib/exec.h Sun Mar 05 10:01:51 2023 +0100 @@ -0,0 +1,7 @@ + +#include <functional> +#include <string> + +void timeit(std::function<void()> f, std::string name = std::string()); + +void benchmarkit(std::function<void()> f, std::string name = std::string(), std::function<void()> setup = [](){});