llvm-project/libcxx/benchmarks/algorithms.bench.cpp

387 lines
11 KiB
C++
Raw Blame History

This file contains ambiguous Unicode characters

This file contains Unicode characters that might be confused with other characters. If you think that this is intentional, you can safely ignore this warning. Use the Escape button to reveal them.

#include <algorithm>
#include <cstdint>
#include <map>
#include <random>
#include <string>
#include <utility>
#include <vector>
#include "CartesianBenchmarks.h"
#include "GenerateInput.h"
#include "benchmark/benchmark.h"
#include "test_macros.h"
namespace {
enum class ValueType { Uint32, Uint64, Pair, Tuple, String };
struct AllValueTypes : EnumValuesAsTuple<AllValueTypes, ValueType, 5> {
static constexpr const char* Names[] = {
"uint32", "uint64", "pair<uint32, uint32>",
"tuple<uint32, uint64, uint32>", "string"};
};
template <class V>
using Value = std::conditional_t<
V() == ValueType::Uint32, uint32_t,
std::conditional_t<
V() == ValueType::Uint64, uint64_t,
std::conditional_t<
V() == ValueType::Pair, std::pair<uint32_t, uint32_t>,
std::conditional_t<V() == ValueType::Tuple,
std::tuple<uint32_t, uint64_t, uint32_t>,
std::string> > > >;
enum class Order {
Random,
Ascending,
Descending,
SingleElement,
PipeOrgan,
Heap,
QuickSortAdversary,
};
struct AllOrders : EnumValuesAsTuple<AllOrders, Order, 7> {
static constexpr const char* Names[] = {"Random", "Ascending",
"Descending", "SingleElement",
"PipeOrgan", "Heap",
"QuickSortAdversary"};
};
// fillAdversarialQuickSortInput fills the input vector with N int-like values.
// These values are arranged in such a way that they would invoke O(N^2)
// behavior on any quick sort implementation that satisifies certain conditions.
// Details are available in the following paper:
// "A Killer Adversary for Quicksort", M. D. McIlroy, Software—Practice &
// ExperienceVolume 29 Issue 4 April 10, 1999 pp 341344.
// https://dl.acm.org/doi/10.5555/311868.311871.
template <class T>
void fillAdversarialQuickSortInput(T& V, size_t N) {
assert(N > 0);
// If an element is equal to gas, it indicates that the value of the element
// is still to be decided and may change over the course of time.
const int gas = N - 1;
V.resize(N);
for (int i = 0; i < N; ++i) {
V[i] = gas;
}
// Candidate for the pivot position.
int candidate = 0;
int nsolid = 0;
// Populate all positions in the generated input to gas.
std::vector<int> ascVals(V.size());
// Fill up with ascending values from 0 to V.size()-1. These will act as
// indices into V.
std::iota(ascVals.begin(), ascVals.end(), 0);
std::sort(ascVals.begin(), ascVals.end(), [&](int x, int y) {
if (V[x] == gas && V[y] == gas) {
// We are comparing two inputs whose value is still to be decided.
if (x == candidate) {
V[x] = nsolid++;
} else {
V[y] = nsolid++;
}
}
if (V[x] == gas) {
candidate = x;
} else if (V[y] == gas) {
candidate = y;
}
return V[x] < V[y];
});
}
template <typename T>
void fillValues(std::vector<T>& V, size_t N, Order O) {
if (O == Order::SingleElement) {
V.resize(N, 0);
} else if (O == Order::QuickSortAdversary) {
fillAdversarialQuickSortInput(V, N);
} else {
while (V.size() < N)
V.push_back(V.size());
}
}
template <typename T>
void fillValues(std::vector<std::pair<T, T> >& V, size_t N, Order O) {
if (O == Order::SingleElement) {
V.resize(N, std::make_pair(0, 0));
} else {
while (V.size() < N)
// Half of array will have the same first element.
if (V.size() % 2) {
V.push_back(std::make_pair(V.size(), V.size()));
} else {
V.push_back(std::make_pair(0, V.size()));
}
}
}
template <typename T1, typename T2, typename T3>
void fillValues(std::vector<std::tuple<T1, T2, T3> >& V, size_t N, Order O) {
if (O == Order::SingleElement) {
V.resize(N, std::make_tuple(0, 0, 0));
} else {
while (V.size() < N)
// One third of array will have the same first element.
// One third of array will have the same first element and the same second element.
switch (V.size() % 3) {
case 0:
V.push_back(std::make_tuple(V.size(), V.size(), V.size()));
break;
case 1:
V.push_back(std::make_tuple(0, V.size(), V.size()));
break;
case 2:
V.push_back(std::make_tuple(0, 0, V.size()));
break;
}
}
}
void fillValues(std::vector<std::string>& V, size_t N, Order O) {
if (O == Order::SingleElement) {
V.resize(N, getRandomString(64));
} else {
while (V.size() < N)
V.push_back(getRandomString(64));
}
}
template <class T>
void sortValues(T& V, Order O) {
switch (O) {
case Order::Random: {
std::random_device R;
std::mt19937 M(R());
std::shuffle(V.begin(), V.end(), M);
break;
}
case Order::Ascending:
std::sort(V.begin(), V.end());
break;
case Order::Descending:
std::sort(V.begin(), V.end(), std::greater<>());
break;
case Order::SingleElement:
// Nothing to do
break;
case Order::PipeOrgan:
std::sort(V.begin(), V.end());
std::reverse(V.begin() + V.size() / 2, V.end());
break;
case Order::Heap:
std::make_heap(V.begin(), V.end());
break;
case Order::QuickSortAdversary:
// Nothing to do
break;
}
}
constexpr size_t TestSetElements =
#if !TEST_HAS_FEATURE(memory_sanitizer)
1 << 18;
#else
1 << 14;
#endif
template <class ValueType>
std::vector<std::vector<Value<ValueType> > > makeOrderedValues(size_t N,
Order O) {
std::vector<std::vector<Value<ValueType> > > Ret;
const size_t NumCopies = std::max(size_t{1}, TestSetElements / N);
Ret.resize(NumCopies);
for (auto& V : Ret) {
fillValues(V, N, O);
sortValues(V, O);
}
return Ret;
}
template <class T, class U>
TEST_ALWAYS_INLINE void resetCopies(benchmark::State& state, T& Copies,
U& Orig) {
state.PauseTiming();
for (auto& Copy : Copies)
Copy = Orig;
state.ResumeTiming();
}
enum class BatchSize {
CountElements,
CountBatch,
};
template <class ValueType, class F>
void runOpOnCopies(benchmark::State& state, size_t Quantity, Order O,
BatchSize Count, F Body) {
auto Copies = makeOrderedValues<ValueType>(Quantity, O);
auto Orig = Copies;
const size_t Batch = Count == BatchSize::CountElements
? Copies.size() * Quantity
: Copies.size();
while (state.KeepRunningBatch(Batch)) {
for (auto& Copy : Copies) {
Body(Copy);
benchmark::DoNotOptimize(Copy);
}
state.PauseTiming();
Copies = Orig;
state.ResumeTiming();
}
}
template <class ValueType, class Order>
struct Sort {
size_t Quantity;
void run(benchmark::State& state) const {
runOpOnCopies<ValueType>(
state, Quantity, Order(), BatchSize::CountElements,
[](auto& Copy) { std::sort(Copy.begin(), Copy.end()); });
}
bool skip() const { return Order() == ::Order::Heap; }
std::string name() const {
return "BM_Sort" + ValueType::name() + Order::name() + "_" +
std::to_string(Quantity);
};
};
template <class ValueType, class Order>
struct StableSort {
size_t Quantity;
void run(benchmark::State& state) const {
runOpOnCopies<ValueType>(
state, Quantity, Order(), BatchSize::CountElements,
[](auto& Copy) { std::stable_sort(Copy.begin(), Copy.end()); });
}
bool skip() const { return Order() == ::Order::Heap; }
std::string name() const {
return "BM_StableSort" + ValueType::name() + Order::name() + "_" +
std::to_string(Quantity);
};
};
template <class ValueType, class Order>
struct MakeHeap {
size_t Quantity;
void run(benchmark::State& state) const {
runOpOnCopies<ValueType>(
state, Quantity, Order(), BatchSize::CountElements,
[](auto& Copy) { std::make_heap(Copy.begin(), Copy.end()); });
}
std::string name() const {
return "BM_MakeHeap" + ValueType::name() + Order::name() + "_" +
std::to_string(Quantity);
};
};
template <class ValueType>
struct SortHeap {
size_t Quantity;
void run(benchmark::State& state) const {
runOpOnCopies<ValueType>(
state, Quantity, Order::Heap, BatchSize::CountElements,
[](auto& Copy) { std::sort_heap(Copy.begin(), Copy.end()); });
}
std::string name() const {
return "BM_SortHeap" + ValueType::name() + "_" + std::to_string(Quantity);
};
};
template <class ValueType, class Order>
struct MakeThenSortHeap {
size_t Quantity;
void run(benchmark::State& state) const {
runOpOnCopies<ValueType>(state, Quantity, Order(), BatchSize::CountElements,
[](auto& Copy) {
std::make_heap(Copy.begin(), Copy.end());
std::sort_heap(Copy.begin(), Copy.end());
});
}
std::string name() const {
return "BM_MakeThenSortHeap" + ValueType::name() + Order::name() + "_" +
std::to_string(Quantity);
};
};
template <class ValueType, class Order>
struct PushHeap {
size_t Quantity;
void run(benchmark::State& state) const {
runOpOnCopies<ValueType>(
state, Quantity, Order(), BatchSize::CountElements, [](auto& Copy) {
for (auto I = Copy.begin(), E = Copy.end(); I != E; ++I) {
std::push_heap(Copy.begin(), I + 1);
}
});
}
bool skip() const { return Order() == ::Order::Heap; }
std::string name() const {
return "BM_PushHeap" + ValueType::name() + Order::name() + "_" +
std::to_string(Quantity);
};
};
template <class ValueType>
struct PopHeap {
size_t Quantity;
void run(benchmark::State& state) const {
runOpOnCopies<ValueType>(
state, Quantity, Order(), BatchSize::CountElements, [](auto& Copy) {
for (auto B = Copy.begin(), I = Copy.end(); I != B; --I) {
std::pop_heap(B, I);
}
});
}
std::string name() const {
return "BM_PopHeap" + ValueType::name() + "_" + std::to_string(Quantity);
};
};
} // namespace
int main(int argc, char** argv) {
benchmark::Initialize(&argc, argv);
if (benchmark::ReportUnrecognizedArguments(argc, argv))
return 1;
const std::vector<size_t> Quantities = {1 << 0, 1 << 2, 1 << 4, 1 << 6,
1 << 8, 1 << 10, 1 << 14,
// Running each benchmark in parallel consumes too much memory with MSAN
// and can lead to the test process being killed.
#if !TEST_HAS_FEATURE(memory_sanitizer)
1 << 18
#endif
};
makeCartesianProductBenchmark<Sort, AllValueTypes, AllOrders>(Quantities);
makeCartesianProductBenchmark<StableSort, AllValueTypes, AllOrders>(
Quantities);
makeCartesianProductBenchmark<MakeHeap, AllValueTypes, AllOrders>(Quantities);
makeCartesianProductBenchmark<SortHeap, AllValueTypes>(Quantities);
makeCartesianProductBenchmark<MakeThenSortHeap, AllValueTypes, AllOrders>(
Quantities);
makeCartesianProductBenchmark<PushHeap, AllValueTypes, AllOrders>(Quantities);
makeCartesianProductBenchmark<PopHeap, AllValueTypes>(Quantities);
benchmark::RunSpecifiedBenchmarks();
}