[libcxx-commits] [libcxx] r367605 - Change default bucket count in hash_set/hash_map.
Eric Fiselier via libcxx-commits
libcxx-commits at lists.llvm.org
Thu Aug 1 12:48:29 PDT 2019
Author: ericwf
Date: Thu Aug 1 12:48:29 2019
New Revision: 367605
URL: http://llvm.org/viewvc/llvm-project?rev=367605&view=rev
Log:
Change default bucket count in hash_set/hash_map.
Previously these types rehashed to a table of 193 elements
upon construction. But this is non-ideal, first because default
constructors should not allocate unless necessary, and second
because 193 is big and can waste a bunch of memory.
This number had previously been chosen to match GCC's implementation.
Added:
libcxx/trunk/test/libcxx/containers/gnu_cxx/hash_map_name_lookup.pass.cpp
- copied, changed from r367356, libcxx/trunk/test/libcxx/containers/gnu_cxx/hash_map.pass.cpp
libcxx/trunk/test/libcxx/containers/gnu_cxx/hash_set_name_lookup.pass.cpp
- copied, changed from r367356, libcxx/trunk/test/libcxx/containers/gnu_cxx/hash_set.pass.cpp
Modified:
libcxx/trunk/include/ext/hash_map
libcxx/trunk/include/ext/hash_set
libcxx/trunk/test/libcxx/containers/gnu_cxx/hash_map.pass.cpp
libcxx/trunk/test/libcxx/containers/gnu_cxx/hash_set.pass.cpp
Modified: libcxx/trunk/include/ext/hash_map
URL: http://llvm.org/viewvc/llvm-project/libcxx/trunk/include/ext/hash_map?rev=367605&r1=367604&r2=367605&view=diff
==============================================================================
--- libcxx/trunk/include/ext/hash_map (original)
+++ libcxx/trunk/include/ext/hash_map Thu Aug 1 12:48:29 2019
@@ -39,14 +39,17 @@ public:
typedef /unspecified/ iterator;
typedef /unspecified/ const_iterator;
- explicit hash_map(size_type n = 193, const hasher& hf = hasher(),
+ hash_map();
+ explicit hash_map(size_type n, const hasher& hf = hasher(),
const key_equal& eql = key_equal(),
const allocator_type& a = allocator_type());
template <class InputIterator>
- hash_map(InputIterator f, InputIterator l,
- size_type n = 193, const hasher& hf = hasher(),
- const key_equal& eql = key_equal(),
- const allocator_type& a = allocator_type());
+ hash_map(InputIterator f, InputIterator l);
+ template <class InputIterator>
+ hash_map(InputIterator f, InputIterator l,
+ size_type n, const hasher& hf = hasher(),
+ const key_equal& eql = key_equal(),
+ const allocator_type& a = allocator_type());
hash_map(const hash_map&);
~hash_map();
hash_map& operator=(const hash_map&);
@@ -502,7 +505,7 @@ public:
typedef __hash_map_iterator<typename __table::iterator> iterator;
typedef __hash_map_const_iterator<typename __table::const_iterator> const_iterator;
- _LIBCPP_INLINE_VISIBILITY hash_map() {__table_.rehash(193);}
+ _LIBCPP_INLINE_VISIBILITY hash_map() { }
explicit hash_map(size_type __n, const hasher& __hf = hasher(),
const key_equal& __eql = key_equal());
hash_map(size_type __n, const hasher& __hf,
@@ -623,7 +626,6 @@ template <class _InputIterator>
hash_map<_Key, _Tp, _Hash, _Pred, _Alloc>::hash_map(
_InputIterator __first, _InputIterator __last)
{
- __table_.rehash(193);
insert(__first, __last);
}
@@ -775,7 +777,7 @@ public:
typedef __hash_map_const_iterator<typename __table::const_iterator> const_iterator;
_LIBCPP_INLINE_VISIBILITY
- hash_multimap() {__table_.rehash(193);}
+ hash_multimap() { }
explicit hash_multimap(size_type __n, const hasher& __hf = hasher(),
const key_equal& __eql = key_equal());
hash_multimap(size_type __n, const hasher& __hf,
@@ -890,7 +892,6 @@ template <class _InputIterator>
hash_multimap<_Key, _Tp, _Hash, _Pred, _Alloc>::hash_multimap(
_InputIterator __first, _InputIterator __last)
{
- __table_.rehash(193);
insert(__first, __last);
}
Modified: libcxx/trunk/include/ext/hash_set
URL: http://llvm.org/viewvc/llvm-project/libcxx/trunk/include/ext/hash_set?rev=367605&r1=367604&r2=367605&view=diff
==============================================================================
--- libcxx/trunk/include/ext/hash_set (original)
+++ libcxx/trunk/include/ext/hash_set Thu Aug 1 12:48:29 2019
@@ -237,7 +237,7 @@ public:
typedef typename __table::const_iterator const_iterator;
_LIBCPP_INLINE_VISIBILITY
- hash_set() {__table_.rehash(193);}
+ hash_set() { }
explicit hash_set(size_type __n, const hasher& __hf = hasher(),
const key_equal& __eql = key_equal());
hash_set(size_type __n, const hasher& __hf, const key_equal& __eql,
@@ -347,7 +347,6 @@ template <class _InputIterator>
hash_set<_Value, _Hash, _Pred, _Alloc>::hash_set(
_InputIterator __first, _InputIterator __last)
{
- __table_.rehash(193);
insert(__first, __last);
}
@@ -459,7 +458,7 @@ public:
typedef typename __table::const_iterator const_iterator;
_LIBCPP_INLINE_VISIBILITY
- hash_multiset() {__table_.rehash(193);}
+ hash_multiset() { }
explicit hash_multiset(size_type __n, const hasher& __hf = hasher(),
const key_equal& __eql = key_equal());
hash_multiset(size_type __n, const hasher& __hf,
@@ -569,7 +568,6 @@ template <class _InputIterator>
hash_multiset<_Value, _Hash, _Pred, _Alloc>::hash_multiset(
_InputIterator __first, _InputIterator __last)
{
- __table_.rehash(193);
insert(__first, __last);
}
Modified: libcxx/trunk/test/libcxx/containers/gnu_cxx/hash_map.pass.cpp
URL: http://llvm.org/viewvc/llvm-project/libcxx/trunk/test/libcxx/containers/gnu_cxx/hash_map.pass.cpp?rev=367605&r1=367604&r2=367605&view=diff
==============================================================================
--- libcxx/trunk/test/libcxx/containers/gnu_cxx/hash_map.pass.cpp (original)
+++ libcxx/trunk/test/libcxx/containers/gnu_cxx/hash_map.pass.cpp Thu Aug 1 12:48:29 2019
@@ -6,31 +6,31 @@
//
//===----------------------------------------------------------------------===//
+
// Prevent emission of the deprecated warning.
#ifdef __clang__
#pragma clang diagnostic ignored "-W#warnings"
#endif
-// Poison the std:: names we might use inside __gnu_cxx to ensure they're
-// properly qualified.
-struct allocator;
-struct pair;
-struct equal_to;
-struct unique_ptr;
#include <ext/hash_map>
+#include <cassert>
#include "test_macros.h"
+#include "count_new.hpp"
-
-namespace __gnu_cxx {
-template class hash_map<int, int>;
+void test_default_does_not_allocate() {
+ DisableAllocationGuard g;
+ ((void)g);
+ {
+ __gnu_cxx::hash_map<int, int> h;
+ assert(h.bucket_count() == 0);
+ }
+ {
+ __gnu_cxx::hash_multimap<int, int> h;
+ assert(h.bucket_count() == 0);
+ }
}
int main(int, char**) {
- typedef __gnu_cxx::hash_map<int, int> Map;
- Map m;
- Map m2(m);
- ((void)m2);
-
- return 0;
+ test_default_does_not_allocate();
}
Copied: libcxx/trunk/test/libcxx/containers/gnu_cxx/hash_map_name_lookup.pass.cpp (from r367356, libcxx/trunk/test/libcxx/containers/gnu_cxx/hash_map.pass.cpp)
URL: http://llvm.org/viewvc/llvm-project/libcxx/trunk/test/libcxx/containers/gnu_cxx/hash_map_name_lookup.pass.cpp?p2=libcxx/trunk/test/libcxx/containers/gnu_cxx/hash_map_name_lookup.pass.cpp&p1=libcxx/trunk/test/libcxx/containers/gnu_cxx/hash_map.pass.cpp&r1=367356&r2=367605&rev=367605&view=diff
==============================================================================
(empty)
Modified: libcxx/trunk/test/libcxx/containers/gnu_cxx/hash_set.pass.cpp
URL: http://llvm.org/viewvc/llvm-project/libcxx/trunk/test/libcxx/containers/gnu_cxx/hash_set.pass.cpp?rev=367605&r1=367604&r2=367605&view=diff
==============================================================================
--- libcxx/trunk/test/libcxx/containers/gnu_cxx/hash_set.pass.cpp (original)
+++ libcxx/trunk/test/libcxx/containers/gnu_cxx/hash_set.pass.cpp Thu Aug 1 12:48:29 2019
@@ -6,29 +6,31 @@
//
//===----------------------------------------------------------------------===//
+
// Prevent emission of the deprecated warning.
#ifdef __clang__
#pragma clang diagnostic ignored "-W#warnings"
#endif
-// Poison the std:: names we might use inside __gnu_cxx to ensure they're
-// properly qualified.
-struct allocator;
-struct pair;
-struct equal_to;
-struct unique_ptr;
+
#include <ext/hash_set>
+#include <cassert>
#include "test_macros.h"
+#include "count_new.hpp"
-namespace __gnu_cxx {
-template class hash_set<int>;
+void test_default_does_not_allocate() {
+ DisableAllocationGuard g;
+ ((void)g);
+ {
+ __gnu_cxx::hash_set<int> h;
+ assert(h.bucket_count() == 0);
+ }
+ {
+ __gnu_cxx::hash_multiset<int> h;
+ assert(h.bucket_count() == 0);
+ }
}
int main(int, char**) {
- typedef __gnu_cxx::hash_set<int> Set;
- Set s;
- Set s2(s);
- ((void)s2);
-
- return 0;
+ test_default_does_not_allocate();
}
Copied: libcxx/trunk/test/libcxx/containers/gnu_cxx/hash_set_name_lookup.pass.cpp (from r367356, libcxx/trunk/test/libcxx/containers/gnu_cxx/hash_set.pass.cpp)
URL: http://llvm.org/viewvc/llvm-project/libcxx/trunk/test/libcxx/containers/gnu_cxx/hash_set_name_lookup.pass.cpp?p2=libcxx/trunk/test/libcxx/containers/gnu_cxx/hash_set_name_lookup.pass.cpp&p1=libcxx/trunk/test/libcxx/containers/gnu_cxx/hash_set.pass.cpp&r1=367356&r2=367605&rev=367605&view=diff
==============================================================================
(empty)
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