Because ShouldIncludeEdge considers the |origin| node as well, it was possible for
the old code to 'miss' nodes and never write them to the core dump even though we
also wrote some edges with the node as referent.
Differential Revision: https://phabricator.services.mozilla.com/D37701
--HG--
extra : moz-landing-system : lando
- 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.
Additionally, change the base class of AutoSuppressGCAnalysis from AutoAssertNoAlloc to AutoAssertNoGC.
In combination, these chances enable passing either JS::AutoCheckCannotGC or JS::AutoSuppressGCAnalysis, depending on whether suppressing the GC analysis is desired or not.
MozReview-Commit-ID: Eg1cl28ezeJ
* * *
Bug 1384513 - Follow-up to fix bustage from template usage of functions with a changed signature, on a CLOSED TREE. r=bustage
MozReview-Commit-ID: 5SsI4DoDwAT
Additionally, change the base class of AutoSuppressGCAnalysis from AutoAssertNoAlloc to AutoAssertNoGC.
In combination, these chances enable passing either JS::AutoCheckCannotGC or JS::AutoSuppressGCAnalysis, depending on whether suppressing the GC analysis is desired or not.
MozReview-Commit-ID: Eg1cl28ezeJ
Simon Giesecke
Jan de Mooij
Tooru Fujisawa
Benjamin Bouvier
Sylvestre Ledru
Nicholas Nethercote
Till Schneidereit
Nick Fitzgerald