- modify line wrap up to 80 chars; (tw=80)
- modify size of tab to 2 chars everywhere; (sts=2, sw=2)
--HG--
extra : rebase_source : 7eedce0311b340c9a5a1265dc42d3121cc0f32a0
extra : amend_source : 9cb4ffdd5005f5c4c14172390dd00b04b2066cd7
Entry storage allocation now occurs on the first lookupForAdd()/put()/putNew().
This removes the need for init() and initialized(), and matches how
PLDHashTable/nsTHashtable work. It also removes the need for init() functions
in a lot of types that are built on top of mozilla::Hash{Map,Set}.
Pros:
- No need for init() calls and subsequent checks.
- No memory allocated for empty tables, which are not that uncommon.
Cons:
- An extra branch in lookup() and lookupForAdd(), but not in put()/putNew(),
because the existing checkOverloaded() can handle it.
Specifics:
- Construction now can take a length parameter.
- init() is removed. Explicit length-setting, when necessary, now occurs in the
constructors.
- initialized() is removed.
- capacity() now returns zero when the entry storage is absent.
- lookupForAdd() is no longer `const`, because it can instantiate the storage,
which requires modifications.
- lookupForAdd() can now return an invalid AddPtr in two cases:
- old: hashing failure (due to OOM in the hasher)
- new: OOM while instantiating entry storage
The existing failure handling paths for the old case work for the new case.
- clear(), finish(), and clearAndShrink() are replaced by clear(), compact(),
and reserve(). The old compactIfUnderloaded() is also removed.
- Capacity computation code is now in its own functions, bestCapacity() and
hashShift(). setTableSizeLog2() is removed.
- uint32_t is used throughout for capacities, instead of size_t, for
consistency with other similar values.
- changeTableSize() now takes a capacity instead of a deltaLog2, and it can now
handle !mTable.
Measurements:
- Total source code size is reduced by over 900 lines. Also, lots of existing
lines got shorter (i.e. two checks were reduced to one).
- Executable size barely changed, down by 2 KiB on Linux64. The extra branches
are compensated for by the lack of init() calls.
- Speed changed negligibly. The instruction count for Bench_Cpp_MozHash
increased from 2.84 billion to 2.89 billion but any execution time change was
well below noise.
Because (a) it's kinda weird, and (b) only used in a single test, where it can
be easily replaced with a vanilla add().
MozReview-Commit-ID: L4RoxFb7yGG
--HG--
extra : rebase_source : 515a5ede5d417686907345ad9069c6a41669dd17
In PLDHashTable the equivalent functions have a "Shallow" prefix, which makes
it clear that they don't measure things hanging off the table. This patch makes
mozilla::Hash{Set,Map} do likewise.
MozReview-Commit-ID: 3kwCJynhW7d
--HG--
extra : rebase_source : 9c03d11f376a9fd4cfd5cfcdc0c446c00633b210
Same approach as the other bug, mostly replacing automatically by removing
'using mozilla::Forward;' and then:
s/mozilla::Forward/std::forward/
s/Forward</std::forward</
The only file that required manual fixup was TestTreeTraversal.cpp, which had
a class called TestNodeForward with template parameters :)
MozReview-Commit-ID: A88qFG5AccP
This was done automatically replacing:
s/mozilla::Move/std::move/
s/ Move(/ std::move(/
s/(Move(/(std::move(/
Removing the 'using mozilla::Move;' lines.
And then with a few manual fixups, see the bug for the split series..
MozReview-Commit-ID: Jxze3adipUh
Tooru Fujisawa
Benjamin Bouvier
Sylvestre Ledru
Jan de Mooij
Nicholas Nethercote
Emilio Cobos Álvarez
Jon Coppeard
Jeff Walden
Wes Kocher
Hannes Verschore
Shu-yu Guo
Terrence Cole
Jim Blandy
Steve Fink