Implements the following simplifications:
(a - b) + b => a
(a * b) + (a * c) => a * (b + c)
Also adds logic to simplification to handle rules that create new operations
that might need simplification, such as the second rule above.
Only perform the second simplification if the multiplies have the add as their
only use. Otherwise this is a deoptimization of size and performance.
At present, TransformationReplaceIdWithSynonym both extracts elements
from composite objects and replaces uses of ids with synonyms. This
new TransformationCompositeExtract class will allow that
transformation to be broken into smaller transformations.
Class TransformationConstructComposite has been renamed to
TransformationCompositeConstruct, to correspond to the name of the
SPIR-V instruction (as is done with e.g. TransformationCopyObject).
Running tests revealed an issue related to checking dominance in
TransformationReplaceIdWithSynonym, which is also fixed here.
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.
Adds a templated class for representing an equivalence relation on a
value data type. This will be used by spirv-fuzz for representing
sets of distinct pieces of data in a shader that are known to have
equal values.
A new pass that gives spirv-fuzz the ability to adjust the memory
operand masks associated with memory access instructions (such as
OpLoad and OpCopy Memory).
Fixes#2940.
We have a check that ensures that the optimizer did not change the
binary when it says that it did not. However, when the binary is
converted back to a binary, we made a decision to remove OpNop
instructions. This means that any spv file that contains a NOP
originally will fail this check.
To get around this, we convert the module to a second binary that keeps
the OpNop instructions. That binary is compared against the original.
Fixes https://crbug.com/1010191
Added exports for libraries. External libraries that themselves use
libraries require all dependencies have exports, so not having exports can
cause major problems when used within other projects.
Install paths for exports are now placed in the proper directories expected
by Windows and *nix systems. Config files are generated as well, which
should work with CMake's find_package() function once installed.
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.
* Validate that selections are structured
WIP
* new checks that switch and conditional branch are proceeded by a
selection merge where necessary
* Don't consider unreachable blocks
* Add some tests
* Changed how labels are marked as seen
* Moved check to more appropriate place
* Labels are now marked as seen when there are encountered in a
terminator instead of when the block is checked
* more tests
* more tests
* Method comment
* new test for a bad case
A refactoring that separates the identification of an instruction from
the identification of a use in an instruction, to enable the former to
be used independently of the latter.
A new pass that allows the fuzzer to change the 'loop control' operand
(and associated literal operands) of OpLoopMerge instructions.
Fixes#2938.
Fixes#2943.
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.
* Remove Impl struct in Reducer; we can re-add it later (in a cleaner fashion) if we need to.
* Add cleanup passes in Reducer; needed so that removal of constants can be disabled during the main passes, and then enabled during cleanup passes, otherwise some main passes can perform worse due to lack of available constants.
* Delete passes: remove op name, remove relaxed precision. And delete associated tests.
* Add more tests for remove unreferenced instructions.
* Always return and write the output file, even if there was a reduction failure.
* Only exit with 0 if the reduction completed or we hit the reduction step limit.
Issue #2919 identifies a problem in spirv-fuzz's ability to determine
when it is safe to add a new control flow edge without breaking
dominance rules. This change adds a (currently disabled) test to
expose the issue, and a comment to document that the current solution
is incomplete.
We want to handle OpKill better. The wrap opkill causes lots of extra
code to be generated, even when they are not needed to avoid the main
problem: OpKill cannot be found directly in a continue construct.
This change will be more selective on which functions the OpKill will be
wrapped and inlining will avoid inlining.
Fixes#2912
Adds a spirv-fuzz option for converting a SPIR-V shader into a shader
that renders red, whilst containing the body of the original shader.
This is for aiding in compiler crash bug reporting.
* Add continue construct analysis to struct cfg analysis
Add the ability to identify which blocks are in the continue construct for a
loop, and to get functions that are called from those blocks, directly or
indirectly.
Part of https://github.com/KhronosGroup/SPIRV-Tools/issues/2912.
There is nothing in the spir-v spec that says the last
instructions in a module cannot be OpLine or OpNoLine.
However, the code that parses the module will simply drop
these instructions.
We add code that will preserve these instructions.
Strip-debug-info is updated to remove these instructions.
Fixes https://crbug.com/1000689.
Because dominance information becomes a bit unreliable when blocks are
unreachable, this change makes it so that the 'dead break'
transformation will not introduce a break to an unreachable block.
Fixes#2907.
The performance of the fuzzer was unacceptable in the 'permute blocks'
transformation, due to dominator analysis being repeatedly invalidated
and recomputed. This change preserves the dominator analysis,
together with the CFG analysis, when a block is moved down.
This change introduces a robust check for whether an index in an
access chain is indexing into a struct, in which case the index needs
to be an OpConstant and cannot be replaced with a synonym.
Fixes#2906.
Issues #2898 and #2900 identify some cases where adding a dead
continue would lead to an invalid module, and these turned out to be
due to the lack of sensible dominance information when a continue
target is unreachable. This change requires that the header of a loop
dominates the loop's continue target if a dead continue is to be
added.
Furthermore, issue #2905 identified a shortcoming in the algorithm
being used to identify when it is OK, from a dominance point of view,
to add a new break/continue edge to a control flow graph. This change
replaces that algorithm with a simpler and more obviously correct
algorithm (that incidentally does not require the new edge to be a
break/continue edge in particular).
Fixes#2898.
Fixes#2900.
Fixes#2905.
Before this change, spirv-fuzz would replace a pointer argument to a
function call with a synonym, which is problematic when the synonym is
not a memory object declaration, since function call arguments are
required to be memory object declarations. This change adds a check
to ensure that such a replacement is not made.
Fixes#2896.
Before this change, spirv-fuzz would replace a constant boolean
argument to an OpPhi with the result of a binary operation, inserting
the instruction to compute the binary operation right before the
OpPhi, leading to an invalid module. This change conservatively
disallows replacing OpPhi arguments. Issue #2902 notes that there is
scope for being less conservative.
Fixes#2897.
