Commit Graph

9 Commits

Author SHA1 Message Date
Alastair Donaldson
9c4481419e
spirv-fuzz: Allow inapplicable transformations to be ignored (#4407)
spirv-fuzz features transformations that should be applicable by
construction. Assertions are used to detect when such transformations
turn out to be inapplicable. Failures of such assertions indicate bugs
in the fuzzer. However, when using the fuzzer at scale (e.g. in
ClusterFuzz) reports of these assertion failures create noise, and
cause the fuzzer to exit early. This change adds an option whereby
inapplicable transformations can be ignored. This reduces noise and
allows fuzzing to continue even when a transformation that should be
applicable but is not has been erroneously created.
2021-07-28 22:59:37 +01:00
Alastair Donaldson
c0833ce620
spirv-fuzz: Remove destructors from FuzzerPass subclasses (#4209)
Subclasses of FuzzerPass no longer needlessly override the default
destructor of FuzzerPass.
2021-03-23 13:31:27 +00:00
Stefano Milizia
7dfd9b8680
spirv-fuzz: Implement MaybeApplyTransformation helper function (#3540)
This function can be used to apply a transformation only if it is
applicable and use it wherever this pattern is used.

Fixes #3530.
2020-07-17 13:01:35 +01:00
Alastair Donaldson
8d4261bc44
spirv-fuzz: Introduce TransformationContext (#3272)
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.
2020-04-02 15:54:46 +01:00
Alastair Donaldson
1b6fd37fa6
spirv-fuzz: Refactor 'split blocks' to identify instructions differently (#2961)
This change refactors the 'split blocks' transformation so that an
instruction is identified via a base, opcode, and number of those
opcodes to be skipped when searching from the base, as opposed to the
previous design which used a base and offset.
2019-10-14 17:00:46 +01:00
Alastair Donaldson
e2e95172df
Rework management of probabilities in spirv-fuzz (#2839)
Before this change there was quite a lot of duplication in the code
being used to choose random percentages, and some of it was incorrect
so that a percentage chance of (100-N)% instead of N% was being used.
Also there was a lot of duplicate code to choose a random index into a
vector.  This change eliminates that duplication (fixing up the
percentage problem), and gets rid of direct access to the random
number generator being used for fuzzing, so that all randomization
requests must go through the FuzzerContext class, discouraging future
ad-hoc uses of the random number generator.
2019-09-10 15:02:25 +01:00
Alastair Donaldson
dfcb5a1e10
Refactor fuzzer transformations (#2694)
Introduced abstract class for transformations, and refactored all transformations to inherit from this abstract class.
2019-06-25 20:49:46 +01:00
Alastair Donaldson
08cc49ec59
Fix bug in 'split blocks', and add tests for fuzzer. (#2658)
There turned out to be a bug in the 'split blocks' transformation due
to blocks being split while they were being iterated over.  This
change fixes that issue, and adds tests that were able to expose the
issue by running the fuzzer on some example shaders.
2019-06-05 21:54:47 +01:00
Alastair Donaldson
1b71e45338
Add "split block" transformation. (#2633)
With this pass, the fuzzer can split blocks in the input module.  This
is mainly useful in order to give other (future) transformations more
opportunities to apply.
2019-05-29 16:42:46 +01:00