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.
Adds a fuzzer pass and transformation to create a composite (array,
matrix, struct or vector) from available constituent components, and
inform the fact manager that each component of the new composite is
synonymous with the id that was used to construct it. This allows the
"replace id with synonym" pass to then replace uses of said ids with
uses of elements extracted from the composite.
Fixes#2858.
A new fuzzer pass that randomly introduces OpCopyObject instructions
that make copies of ids, and uses the fact manager to record the fact
that an id %id is synonymous with an id generated by an OpCopyObject
applied to %id. (A future pass will exploit such synonym facts.)
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.
