Some transformations (e.g. TransformationAddFunction) rely on running
the validator to decide whether the transformation is applicable. A
recent change allowed spirv-fuzz to take validator options, to cater
for the case where a module should be considered valid under
particular conditions. However, validation during the checking of
transformations had no access to these validator options.
This change introduced TransformationContext, which currently consists
of a fact manager and a set of validator options, but could in the
future have other fields corresponding to other objects that it is
useful to have access to when applying transformations. Now, instead
of checking and applying transformations in the context of a
FactManager, a TransformationContext is used. This gives access to
the fact manager as before, and also access to the validator options
when they are needed.
This change adds fuzzer passes that sprinkle loads and stores into a
module at random, with stores restricted to occur in either dead
blocks, or to use pointers for which it is known that the pointee
value does not influence the module's overall behaviour.
The change also generalises the VariableValueIsArbitrary fact to
PointeeValueIsIrrelevant, to allow stores through access chains or
object copies of variables whose values are known to be irrelevant.
The change includes some other minor refactorings.
If the fuzzer object-copies a pointer we would like to be able to
perform loads from the copy (and stores to it, if its value is known
not to matter). Undefined and null pointers present a problem here,
so this change disallows copying them.
* Validate that if a construct contains a header and it's merge is
reachable, the construct also contains the merge
* updated block merging to not merge into the continue
* update inlining to mark the original block of a single block loop as
the continue
* updated some tests
* remove dead code
* rename kBlockTypeHeader to kBlockTypeSelection for clarity
When a data synonym fact about two composites is added, data synonym
facts between all sub-components of the composites are also added.
Furthermore, when data synonym facts been all sub-components of two
composites are known, a data synonym fact relating the two composites
is added. Identification of this case is done in a lazy manner, when
questions about data synonym facts are asked.
The change introduces helper methods to get the size of an array type
and the number of elements of a struct type, and fixes
TransformationCompositeExtract to invalidate analyses appropriately.
This change fixes a bug in EquivalenceRelation, changes the interface
of EquivalenceRelation to avoid exposing (potentially
nondeterministic) unordered sets, and changes the interface of
FactManager to allow querying data synonyms directly. These interface
changes have required a lot of corresponding changes to client code
and tests.
This change uses the recently-added equivalence relation class to
re-work the way synonyms between data values are managed by the fact
manager.
The tests for 'transformation_replace_id_with_synonym' have been
temporarily removed. This is because those tests are going to be
split into a number of test classes in an upcoming PR, once some other
refactorings have been applied, and it would be burdensome to
temporarily refactor all the tests to be in a working state for this
intermediate change.
This transformation can introduce an instruction that uses
OpCopyObject to make a copy of some other result id. This change
introduces the transformation, but does not yet introduce a fuzzer
pass to actually apply it.
