This is required, so that QHash and QSet can hold more
than 2^32 items on 64 bit platforms.
The actual hashing functions for strings are still 32bit, this will
be changed in a follow-up commit.
Change-Id: I4372125252486075ff3a0b45ecfa818359fe103b
Reviewed-by: Mårten Nordheim <marten.nordheim@qt.io>
A brand new QHash implementation using a faster and more memory efficient data
structure than the old QHash.
A new implementation for QHash. Instead of a node based approach as the old
QHash, this implementation now uses a two stage lookup table. The total
amount of buckets in the table are divided into spans of 128 entries.
Inside each span, we use an array of chars to index into a storage area
for the span.
The storage area for each span is a simple array, that gets (re-)allocated
with size increments of 16 items. This gives an average memory overhead of
8*sizeof(struct{ Key; Value; }) + 128*sizeof(char) + 16 for each span.
To give good performance and avoid too many collisions, the array keeps its
load factor between .25 and .5 (and grows and rehashes if the load factor goes
above .5).
This design allows us to keep the memory overhead of the Hash very small, while
at the same time giving very good performance. The calculated overhead for a
QHash<int, int> comes to 1.7-3.3 bytes per entry and to 2.2-4.3 bytes for
a QHash<ptr, ptr>.
The new implementation also completely splits the QHash and QMultiHash classes.
One behavioral change to note is that the new QHash implementation will not
provide stable references to nodes in the hash when the table needs to grow.
Benchmarking using https://github.com/Tessil/hash-table-shootout shows
very nice performance compared to many different hash table implementation.
Numbers shown below are for a hash<int64, int64> with 1 million entries. These
numbers scale nicely (mostly in a linear fashion with some variation due to
varying load factors) to smaller and larger tables. All numbers are in seconds,
measured with gcc on Linux:
Hash table random random random random reads full
insertion insertion full full after iteration
(reserved) deletes reads deletes
------------------------------------------------------------------------------
std::unordered_map 0,3842 0,1969 0,4511 0,1300 0,1169 0,0708
google::dense_hash_map 0,1091 0,0846 0,0550 0,0452 0,0754 0,0160
google::sparse_hash_map 0,2888 0,1582 0,0948 0,1020 0,1348 0,0112
tsl::sparse_map 0,1487 0,1013 0,0735 0,0448 0,0505 0,0042
old QHash 0,2886 0,1798 0,5065 0,0840 0,0717 0,1387
new QHash 0,0940 0,0714 0,1494 0,0579 0,0449 0,0146
Numbers for hash<std::string, int64>, with the string having 15 characters:
Hash table random random random random reads
insertion insertion full full after
(reserved) deletes reads deletes
--------------------------------------------------------------------
std::unordered_map 0,4993 0,2563 0,5515 0,2950 0,2153
google::dense_hash_map 0,2691 0,1870 0,1547 0,1125 0,1622
google::sparse_hash_map 0,6979 0,3304 0,1884 0,1822 0,2122
tsl::sparse_map 0,4066 0,2586 0,1929 0,1146 0,1095
old QHash 0,3236 0,2064 0,5986 0,2115 0,1666
new QHash 0,2119 0,1652 0,2390 0,1378 0,0965
Memory usage numbers (in MB for a table with 1M entries) also look very nice:
Hash table Key int64 std::string (15 chars)
Value int64 int64
---------------------------------------------------------
std::unordered_map 44.63 75.35
google::dense_hash_map 32.32 80,60
google::sparse_hash_map 18.08 44.21
tsl::sparse_map 20.44 45,93
old QHash 53.95 69,16
new QHash 23.23 51,32
Fixes: QTBUG-80311
Change-Id: I5679734144bc9bca2102acbe725fcc2fa89f0dff
Reviewed-by: Thiago Macieira <thiago.macieira@intel.com>
This pulls the CMake port, which not only adds CMake files but also
modifies existing code. A brief summary of "seemingly unrelated" changes:
* configure.json was re-formatted to not use multi-line strings. That
is an extension of the Qt JSON parser but not JSON compliant, which
is needed for the configure.json-to-cmake conversion script (python).
* Some moc inclusions were added due to CMake's slightly different way
of handling moc. With the changes the files build with qmake and cmake.
* Since CMake just grep's for the Q_OBJECT macro to determine whether to
call moc (instead of doing pre-processing like qmake), the existing use
of "Q_OBJECT" in our documentation was changed to \Q_OBJECT, which cmake
doesn't see and which is now a qdoc macro.
* QTestLib's qFindTestData was extended to also search in the source
directory known at build time.
What this change also brings is a new way of building modules in Coin by using
YAML configuration files that describe the steps of building and testing in Coin
specific terms. The platform configuration files in qt5 are instructed to use the
old Coin built-in way of testing ("UseLegacyInstructions" feature) but for any
configurations that do not have this, these yaml files in the coin/ sub-directory
are used and shared across repositories.
Change-Id: I1d832c3400e8d6945ad787024ba60e7440225c08
Remove support for reverse iteration over a QSet.
Change-Id: I1e9c986a118aea4ebeb7fcdceb41e9ce6593cdb6
Reviewed-by: Simon Hausmann <simon.hausmann@qt.io>
The concept was a nice idea to avoid accidental detach() calls
in implicitly shared containers, but it conflicts with a C++11
compatible API for them, with signatures for modifying methods
taking a const_iterator as argument and returning an iterator
(e.g. iterator erase(const_iterator)).
Change-Id: Ia33124bedbd260774a0a66f49aedd84e19c9971b
Reviewed-by: Simon Hausmann <simon.hausmann@qt.io>
Note that android builds will be broken after this merge and
regeneration, because we don't currently handle the minimum required
changes that were brought in with the Android multi ABI support
that comes from 5.14.
This will have to be addressed in a separate change.
For now the build on Android will fail while compiling due to incorrect
generation of LIB_SUFFIX with QT_ARCH.
Change-Id: Ia4a871f4b7ddd0da11caf5f34e10a599a97bb55d
Reviewed-by: Simon Hausmann <simon.hausmann@qt.io>
Reviewed-by: Qt CMake Build Bot
Amends 2e1763d83a.
The new range ctors need deduction guides, since the compiler can't
deduce the value_type from a pair of iterators.
Change-Id: I3ec1e5f91305b317c443b6a70246be416b55bad9
Reviewed-by: Volker Hilsheimer <volker.hilsheimer@qt.io>
Reviewed-by: Thiago Macieira <thiago.macieira@intel.com>
... except for tests, which manually undefine the macro.
Like QT_NO_FOREACH, this is a technical way to keep JSI-free
modules JSI-free going forward.
Change-Id: Icf1342da00a700f42f9e32a253d1cdb94c38dd7e
Reviewed-by: Lars Knoll <lars.knoll@qt.io>
From Qt 5.7 -> tools & applications are lisenced under GPL v3 with some
exceptions, see
http://blog.qt.io/blog/2016/01/13/new-agreement-with-the-kde-free-qt-foundation/
Updated license headers to use new GPL-EXCEPT header instead of LGPL21 one
(in those files which will be under GPL 3 with exceptions)
Change-Id: I42a473ddc97101492a60b9287d90979d9eb35ae1
Reviewed-by: Thiago Macieira <thiago.macieira@intel.com>
Reviewed-by: Lars Knoll <lars.knoll@theqtcompany.com>
Prefer QCOMPARE over QVERIFY for equality and use QLatin1String().
Change-Id: If226a0fc7b25be3e6774c7e36ca1e6f99234e5dd
Reviewed-by: Jędrzej Nowacki <jedrzej.nowacki@theqtcompany.com>
Now all Qt sequential containers consistently provide reverse iterators.
The associative ones, by way of not returning std::pair from op*, can't
just use std::reverse_iterator. They would miss .key() and .value() methods.
So that has to wait for 5.7.
The reverse versions of the new key_iterators can also just use
std::reverse_iterator, but I'm afraid that after bikeshedding over
keyRBegin() vs. rKeyBegin() vs. reverseKeyBegin() vs. rkbegin()
vs. krbegin() (<-- of course, what else?), it would anyway be too
late for 5.6, so defer, too.
[ChangeLog][QtCore][QLinkedList/QSet] Added rbegin(), crbegin(), rend(), crend(),
and reverse_iterator and const_reverse_iterator typedefs.
Task-number: QTBUG-25919
Change-Id: I58316fffade469e9a42c61d7aa1455ae3443fd94
Reviewed-by: Sérgio Martins <sergio.martins@kdab.com>
Reviewed-by: Olivier Goffart (Woboq GmbH) <ogoffart@woboq.com>
In some cases it's not possible to use QT_HASH_SEED, specially when
we need to set the environment variable from inside the application,
as dynamically loaded libraries or plugins may create static QHash
instances. That would set qt_qhash_seed to a value different from
-1 and skip the env var value.
For those cases, and when we still want to set qt_qhash_seed, we
provide a way to enforce its value.
Auto-tests accessing qt_qhash_seed directly have been updated
accordingly. Usage in qdoc, uic and rcc has been left as is
for the time being.
Change-Id: I3b35b4fa0223c83b1348a6508641905a2a63266f
Reviewed-by: Lars Knoll <lars.knoll@theqtcompany.com>
The keyword no longer has a meaning for the new CI.
Change-Id: Ibcea4c7a82fb7f982cf4569fdff19f82066543d1
Reviewed-by: Simon Hausmann <simon.hausmann@theqtcompany.com>
The pattern "mySet.intersect(other).isEmpty()" has been spotted in
the wild and in Qt codebase. intersects() is much cheaper because it
bails out as soon as we find one common item and doesn't do any
allocations.
[ChangeLog][QtCore][QSet] Added intersects().
Change-Id: I44a350dc4cdb9deb835a23eee99fc99d6ca24c82
Reviewed-by: Marc Mutz <marc.mutz@kdab.com>
Qt copyrights are now in The Qt Company, so we could update the source
code headers accordingly. In the same go we should also fix the links to
point to qt.io.
Outdated header.LGPL removed (use header.LGPL21 instead)
Old header.LGPL3 renamed to header.LGPL3-COMM to match actual licensing
combination. New header.LGPL-COMM taken in the use file which were
using old header.LGPL3 (src/plugins/platforms/android/extract.cpp)
Added new header.LGPL3 containing Commercial + LGPLv3 + GPLv2 license
combination
Change-Id: I6f49b819a8a20cc4f88b794a8f6726d975e8ffbe
Reviewed-by: Matti Paaso <matti.paaso@theqtcompany.com>
...using qHashRangeCommutative(). Also add a test.
[ChangeLog][QtCore][QSet] Can now be used as the key in QSet, QHash.
Change-Id: Ie7c81d257a3b324fc03d394fa7c9fcf0c6fb062a
Reviewed-by: Thiago Macieira <thiago.macieira@intel.com>
Add a test that checks that QSet keeps the first of the elements
that have equal value. This is documented, but inconsistent with
values in a QHash, which keeps the last element with equal key.
Document this as a test. That way, we'll be informed when the
behavior changes (e.g. by a port to std::unordered_set).
Change-Id: I4ca1718bb86599b925b3ccd13b0856917cd4ce67
Reviewed-by: Olivier Goffart <ogoffart@woboq.com>
No actual reason for this test, except my curiority. Then again, it's
good to have this check, too.
Change-Id: I815fce7e4dbe76e21cac29beb1dbfc1083191d24
Reviewed-by: Olivier Goffart <ogoffart@woboq.com>
Change copyrights and license headers from Nokia to Digia
Change-Id: If1cc974286d29fd01ec6c19dd4719a67f4c3f00e
Reviewed-by: Lars Knoll <lars.knoll@digia.com>
Reviewed-by: Sergio Ahumada <sergio.ahumada@digia.com>
Qt 5.0 beta requires changing the default to the 5.0 API, disabling
the deprecated code. However, tests should test (and often do) the
compatibility API too, so turn it back on.
Task-number: QTBUG-25053
Change-Id: I8129c3ef3cb58541c95a32d083850d9e7f768927
Reviewed-by: Lars Knoll <lars.knoll@nokia.com>
Reviewed-by: Olivier Goffart <ogoffart@woboq.com>
C++11 adds cbegin()/cend() functions for the same reason Qt has
constBegin()/constEnd(). This patch adds these functions to the
Qt containers with the same implementation as constBegin()/constEnd().
It also fixes the return types in the documentation of existing
constFind() functions (documentation only).
C++11 only adds cbegin()/cend() (and crbegin()/crend(), which Qt doesn't have).
In particular, it doesn't add cfind(), so I didn't supply these, even though
Qt comes with constFind().
This is a forward-port of https://qt.gitorious.org/qt/qt/merge_requests/1365.
Change-Id: Ida086b64246b24e25254eafbcb06c8e33388502b
Reviewed-by: Olivier Goffart <ogoffart@woboq.com>
As in the past, to avoid rewriting various autotests that contain
line-number information, an extra blank line has been inserted at the
end of the license text to ensure that this commit does not change the
total number of lines in the license header.
Change-Id: I311e001373776812699d6efc045b5f742890c689
Reviewed-by: Rohan McGovern <rohan.mcgovern@nokia.com>
These comments were mostly empty or inaccurate. Appropriate naming of
tests and appropriate placement of tests within the directory tree
provide more reliable indicators of what is being tested.
Change-Id: Ib6bf373d9e79917e4ab1417ee5c1264a2c2d7027
Reviewed-by: Rohan McGovern <rohan.mcgovern@nokia.com>
Remove references to the old bug tracker. The data from the old bug
tracker is no longer accessible, so these markers are meaningless.
Change-Id: Ib9d029d52b70fd0a512b9532d65f03763eabfe57
Reviewed-by: Rohan McGovern <rohan.mcgovern@nokia.com>
qttest_p4.prf was added as a convenience for Qt's own autotests in Qt4.
It enables various crufty undocumented magic, of dubious value.
Stop using it, and explicitly enable the things from it which we want.
Change-Id: I7c1ffe9c8c294dbdc988e1582e580b1ed3f4593e
Reviewed-by: Jason McDonald <jason.mcdonald@nokia.com>
Symbian is not a supported platform for Qt5, so this code is no longer
required.
Change-Id: I1172e6a42d518490e63e9599bf10579df08259aa
Reviewed-on: http://codereview.qt-project.org/5657
Reviewed-by: Rohan McGovern <rohan.mcgovern@nokia.com>
