feedc0de/boost_unordered
1
0
Fork 0
forked from boostorg/unordered
Code Pull Requests Activity

Optimize emplace() for exactly a value_type or init_type argument (#227)

Browse Source 
* Add structs to count special member functions

* Add failing emplace tests, that will pass after making the optimization

* Optimize emplace() to not allocate when we already have a value_type or init_type

* Fix newly failing cfoa tests
This commit is contained in:
Braden Ganetsky
2023-12-31 18:56:14 +01:00
committed by GitHub
parent 75a94781d5
commit 67c5cdb3a6
10 changed files with 418 additions and 37 deletions
Download Patch File Download Diff File Expand all files Collapse all files
test/cfoa/emplace_tests.cpp
+69 -1
View File
@@ -170,6 +170,74 @@ namespace {
}
} lvalue_emplace_or_visit;
struct copy_emplacer_type
{
template <class T, class X> void operator()(std::vector<T>& values, X& x)
{
static constexpr auto value_type_cardinality =
value_cardinality<typename X::value_type>::value;
std::atomic<std::uint64_t> num_inserts{0};
thread_runner(values, [&x, &num_inserts](boost::span<T> s) {
for (auto const& r : s) {
bool b = x.emplace(r);
if (b) {
++num_inserts;
}
}
});
BOOST_TEST_EQ(num_inserts, x.size());
BOOST_TEST_EQ(raii::default_constructor, 0u);
BOOST_TEST_EQ(raii::copy_constructor, value_type_cardinality * x.size());
BOOST_TEST_GT(raii::move_constructor, 0u);
BOOST_TEST_EQ(raii::copy_assignment, 0u);
BOOST_TEST_EQ(raii::move_assignment, 0u);
}
} copy_emplacer;
struct move_emplacer_type
{
template <class T, class X> void operator()(std::vector<T>& values, X& x)
{
static constexpr auto value_type_cardinality =
value_cardinality<typename X::value_type>::value;
std::atomic<std::uint64_t> num_inserts{0};
thread_runner(values, [&x, &num_inserts](boost::span<T> s) {
for (auto& r : s) {
bool b = x.emplace(std::move(r));
if (b) {
++num_inserts;
}
}
});
BOOST_TEST_EQ(num_inserts, x.size());
BOOST_TEST_EQ(raii::default_constructor, 0u);
#if defined(BOOST_MSVC)
#pragma warning(push)
#pragma warning(disable : 4127) // conditional expression is constant
#endif
if (std::is_same<T, typename X::value_type>::value &&
!std::is_same<typename X::key_type,
typename X::value_type>::value) { // map value_type can only be
// copied, no move
BOOST_TEST_EQ(raii::copy_constructor, x.size());
} else {
BOOST_TEST_EQ(raii::copy_constructor, 0u);
}
#if defined(BOOST_MSVC)
#pragma warning(pop) // C4127
#endif
BOOST_TEST_GT(raii::move_constructor, value_type_cardinality * x.size());
BOOST_TEST_EQ(raii::copy_assignment, 0u);
BOOST_TEST_EQ(raii::move_assignment, 0u);
}
} move_emplacer;
template <class X, class GF, class F>
void emplace(X*, GF gen_factory, F emplacer, test::random_generator rg)
{
@@ -220,7 +288,7 @@ UNORDERED_TEST(
((map)(set))
((value_type_generator_factory)(init_type_generator_factory))
((lvalue_emplacer)(norehash_lvalue_emplacer)
(lvalue_emplace_or_cvisit)(lvalue_emplace_or_visit))
(lvalue_emplace_or_cvisit)(lvalue_emplace_or_visit)(copy_emplacer)(move_emplacer))
((default_generator)(sequential)(limited_range)))
// clang-format on