We currently erroneously keep mentions of class instantiations, which
can lead to bad performance on template-heavy code bases. We never
want to link those anyway, so we can simply suppress them.
Also exclude templates as their names are not canonical.
The test changes in `isfromtemplateinstantiation/` are the inverses of
what we got in 34c9892f7, which should be a good thing.
These tests exercise the problematic cases where a variable can appear
to have multiple types because of how we fail to account for qualified
names when comparing type names.
With the new formulation, we can join on function and index at the
same time, leading to significant performance gains on large code
bases that use templates extensively.
This query gets optimized badly, and it has started timing out when we
run it on our own code base. Most of the evaluation time is spent in an
RA predicate named `#select#cpe#1#f#antijoin_rhs#1`, which takes 1m36s a
Wireshark snapshot.
This restructuring of the code makes the problematic RA predicate go
away.
On a snapshot of Postgres, evaluation of
`getNextExplicitlyInitializedElementAfter#fff#antijoin_rhs#1` took
forever, preventing the computation of the IR. I haven't been able to
reproduce it with a small test case, but the implementation of
`getNextExplicitlyInitializedElementAfter` was fragile because it called
the inline predicate `ArrayAggregateLiteral.isInitialized`. It also
seemed inefficient that `getNextExplicitlyInitializedElementAfter` was
computed for many values of its parameters that were never needed by the
caller.
This commit replaces `getNextExplicitlyInitializedElementAfter` with a
new predicate named `getEndOfValueInitializedRange`, which should have
the same behavior but a more efficient implementation. It uses a helper
predicate `getNextExplicitlyInitializedElementAfter`, which shares its
name with the now-deleted predicate but has behavior that I think
matches the name.
The overrides of `Instruction.getOperandMemoryAccess` did not relate
`this` to any of its other parameters, which made it attempt to compute
the Cartesian product of `Instruction` and `TPhiOperand`. This happened
only during computation of aliased SSA. Perhaps the optimizer was able
to eliminate the CP for the non-aliased SSA computation.
With this change, I'm able to compute aliased SSA for medium-sized
snapshots.
Instead of computing these two things in one predicate, they are
computed in separate predicates and then joined. This splits the
predicate `getInstruction`, which took 81s before, into predicates that
together take 20s on a medium-sized db.
Moved IR flavors into "implementation", with internal files under "implementation/internal". Made `IRBlockConstruction` just a nested module of `IRConstruction`/`SSAConstruction`, so it gets picked up from the `Construction` parameter of the `IR` module, rather than being picked up just from being in the same directory as `IRBlock`.
This change makes the public IR.qll module resolve to the flavor of the IR that we want queries to use. Today, this is the aliased SSA flavor of the IR. Should we add additional IR iterations in the future, we'll update IR.qll to resolve to whichever one we consider the default.
I moved the PrintIR.ql and IRSanity.ql queries into the internal directories of the corresponding flavors. There's still a PrintIR.ql and an IRSanity.ql in the public IR directory, which use the same IR flavor as the public IR.qll.
There are no real code changes here, other than to fix up `import`s. All tests still hae the same output, as expected.
A future commit will hide the IR flavors other than the one we want queries to use directly.
Instead of computing these two things in one predicate, they are
computed in separate predicates and then joined. This splits the
predicate `primitive_basic_block_member`, which took 77s before, into
predicates that together take 18s on a medium-sized db.
By extending this class, a class can define its own `getLocation`
predicate without participating in the dispatch hierarchy of
`getLocation` as defined on `Element`. Classes wanting to override their
location previously had to define `getURL` or `hasLocationInfo` instead
and rely on these predicates not being defined on future versions of
`Element`.
gmtime and gmtime_r take a time_t pointer, so have to store the value
of time(NULL) on the stack.
Signed-off-by: Ole Herman Schumacher Elgesem <oleherman93@gmail.com>
