spirv-fuzz has useful tests that run the fuzzer and shrinker, to give
the whole tool a good shake up, effectively "fuzzing the fuzzer". The
problems that this detects are sensitive to the source of randomness
that is used, which can change from test platform to test platform.
It is thus not a good idea to run these tests by default during
continuous integration - they may end up failing due to environtal
factors, making it look like an unrelated change has broken the fuzzer
when really the fuzzer has revealed an already-existing bug in itself.
This change makes the tests disabled by default; they can enabled
during dedicated testing of the fuzzer.
The warp-opkill pass is generating incorrect code. It is placing an
OpUnreachable at the end of a basic block, when the block can be
reached. We can't reach the end of the block, but we can reach the end.
Instead we will add a return instruction.
Fixes#2875.
Many of the places in copy propagate arrays assumes that integer constant will be defined by an OpConstant instruction. That is not always true. We fix these spots by allowing for an OpConstantNull.
If the fuzzer's fact manager knows that ids A and B are synonymous, it
can replace a use of A with a use of B, so long as various conditions
hold (e.g. the definition of B must dominate the use of A, and it is
not legal to replace a use of an OpConstant in a struct's access chain
with a synonym that is not an OpConstant).
This change adds a fuzzer pass to sprinke such synonym replacements
through the module.
* When input or result is a pointer type also allow 32-bit integer
vectors for the other type
* Relaxation only applies to SPIR-V 1.5 or in the presence of
SPV_KHR_physical_storage_buffer
* new tests
* Vulkan specific checks
* storage buffer variables must be structs or arrays of structs
* storage buffer struct must be Block decorated
* uniform struct must be Block or BufferBlock decorated
* new tests
* Ensure same enum values have consistent extension lists
* val: fix checking of capabilities
The operand for an OpCapability should only be
checked for the extension or core version.
The InstructionPass registers a capability, and all its implied
sub-capabilities before actually checking the operand to an
OpCapability.
* Add basic support for SPIR-V 1.5
- Adds SPV_ENV_UNIVERSAL_1_5
- Command line tools default to spv1.5 environment
- SPIR-V 1.5 incorporates several extensions. Now the disassembler
prefers outputing the non-EXT or non-KHR names. This requires
updates to many tests, to make strings match again.
- Command line tests: Expect SPIR-V 1.5 by default
* Test validation of SPIR-V 1.5 incorporated extensions
Starting with 1.5, incorporated features no longer require
the associated OpExtension instruction.
If an OpKill instruction is inlined into a continue construct, then the
spir-v is no longer valid. To avoid this issue, we do inline into an
OpKill at all. This method was chosen because it is difficult to keep
track of whether or not you are in a continue construct while changing
the function that is being inlined into. This will work well with wrap
OpKill because every will still be inlined except for the OpKill
instruction itself.
Fixes#2554Fixes#2433
This reverts commit aa9e8f5380.
The implementation of these passes had overlooked the fact that adding
a new edge to a control flow graph can change dominance information.
Adding a dead break/continue risks causing uses to no longer be
dominated by their definitions. This change introduces various tests
to expose such scenarios, and augments the preconditions for these
transformations with checks to guard against the situation.
* Handle id overflow in the ssa rewriter.
Remove LocalSSAElim pass at the same time. It does the same thing as the SSARewrite pass. Then even share almost all of the same code.
Fixes crbug.com/997246
The first pass applies the RelaxedPrecision decoration to all executable
instructions with float32 based type results. The second pass converts
all executable instructions with RelaxedPrecision result to the equivalent
float16 type, inserting converts where necessary.
Add the first steps to removing the AMD extension VK_AMD_shader_ballot.
Splitting up to make the PRs smaller.
Adding utilities to add capabilities and change the version of the
module.
Replaces the instructions:
OpGroupIAddNonUniformAMD = 5000
OpGroupFAddNonUniformAMD = 5001
OpGroupFMinNonUniformAMD = 5002
OpGroupUMinNonUniformAMD = 5003
OpGroupSMinNonUniformAMD = 5004
OpGroupFMaxNonUniformAMD = 5005
OpGroupUMaxNonUniformAMD = 5006
OpGroupSMaxNonUniformAMD = 5007
and extentend instructions
WriteInvocationAMD = 3
MbcntAMD = 4
Part of #2814
* Refactor instruction folders
We want to refactor the instruction folder to allow different sets of
rules to be added to the instruction folder. We might want different
sets of rules in different circumstances.
We also need a way to add rules for extended instructions. Changes are
made to the FoldingRules class and ConstFoldingRules class to enable
that.
We added tests to check that we can fold extended instructions using the
new framework.
At the same time, I noticed that there were two tests that did not tests
what they were suppose to. They could not be easily salvaged. #2813 was
opened to track adding the new tests.
Adds a reduction pass that removes OpDecorate and OpMemberDecorate
instructions that annotate instructions and members with
RelaxedPrecision. As well as being useful in its own right, removing
such references allows other passes to remove further instructions.
Now we need to handle id overflow when we overflow while replacing uses of the variable. While looking at this code, I noticed an error in the way we handle access chains that cannot be replaced because of overflow. Name it will make some change, and then give up by returning SuccessWithoutChange. But it was changed.
This is fixed up by returning Failure if we notice the error at the time of rewriting the users. This is for both id overflow or out-of-bounds accesses.
Code is added to "CheckUses" to remove variables that have out-of-bounds accesses from the candidate list, so we don't even try to rewrite its uses.
Fixes https://crbug.com/995032
If we run out of ids when creating a new variable, sroa does not recognize
the error, and continues doing work. This leads to segmentation faults.
Fixes https://crbug/969655
Fixes#2793
* Don't special case matrix validation compared to other composites
* just check the constituents are constants or undefs
* later checking validates the column type
* new test
We are no able to inline OpKill instructions into a continue construct.
See #2433. However, we have to be able to inline to correctly do
legalization. This commit creates a pass that will wrap OpKill
instructions into a function of its own. That way we are able to inline
the rest of the code.
The follow up to this will be to not inline any function that contains
an OpKill.
Fixes#2726
This also fixes ADCE to not remove possibly needed OpTypeForwardPointer.
The bug, its fix and the corresponding test have a circular dependency
with the extension, so they are packaged together.
If a member of a struct has a relaxed precision, sroa will not split the
struct. This means we do not get all cases. This commit handles these
cases. The other part is that the decoration needs to be passed on to
the new variables.
Fixes#2786
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.
Fixes#2768
* In scalar replacement, interpret access chain indexes as signed counts
* Use Constant::GetSignExtendedValue and Constant::GetZeroExtendedValue
where appropriate
* new tests
spirv-opt: Add --graphics-robust-access
Clamps access chain indices so they are always
in bounds.
Assumes:
- Logical addressing mode
- No runtime-array-descriptor-indexing
- No variable pointers
Adds stub code for clamping coordinate and samples
for OpImageTexelPointer.
Adds SinglePassRunAndFail optimizer test fixture.
Android.mk: add source/opt/graphics_robust_access_pass.cpp
Adds Constant::GetSignExtendedValue, Constant::GetZeroExtendedValue
This fixes#2608.
The original test case had an out-of-bounds reference that ended up
folding into OpCompositeExtract that was indexing right outside the
constant composite.
The returned constant would then cause a segfault during constant
propagation.
Fixes#2764
* Don't replace all uses when simplifying instructions, instead only
update non-debug, non-decoration uses
* added a test
* Add a new version of RAUW that takes a predicate to decide whether to
replace the use or not
* used in simplification pass
* Fix#2609 - Handle out-of-bounds scalar replacements.
When SROA tries to do a replacement for an OpAccessChain that is exactly
one element out of bounds, the code was trying to access its internal
array of replacements and segfaulting.
This protects the code from doing this, and it additionally fixes the
way SROA works by not returning failure when it refuses to do a
replacement. Instead of failing the optimization pass, SROA will now
simply refuse to do the replacement and keep going.
Additionally, this patch fixes the SROA logic to now return a proper status so we can
correctly state that the pass made no changes to the IR if it only found
invalid references.
The recently added fuzzer_replayer and fuzzer_shrinker tests were
rather heavyweight and were leading to CI timeouts. This change
reduces the runtime of those tests by having them do fewer iterations.
Merge return expects unreachable merge block to look a certain way, and
unreachable continue blocks to look a certain way. What if an
unreachable block is both a merge and a continue? The continue is
suppose to take precedent, but merge-return implements it with the merge
taking precedent. This change flips that around.
Fixes#2746
Similar to the existing 'add dead breaks' pass, this adds a pass to
add dead continues to blocks in loops where such a transformation is
viable. Various functionality common to this new pass and 'add dead
breaks' has been factored into 'fuzzer_util', and some small
improvements to 'add dead breaks' that were identified while reviewing
that code again have been applied.
Fixes#2719.
* Process OpDecorateId in ADCE
When there is an OpDecorateId instruction that is live,
the ids that is references must be kept live. This change
adds them to the worklist.
I've also updated a validator check to allow OpDecorateId
to be able to apply to decoration groups.
Fixes#1759.
* Remove dead code.
In merge return, we need to know the original dominator for a block in order to
traverse code from the original dominator to the new dominator and add
appropriate Phi nodes. The current code gets this wrong because the dominator
tree is build as needed. The first time we get the immediate dominator for a
function we just built the dominator tree and it takes into account that a
block has been split. The second time it does not.
This inconsistency needs to be fixed. We do that by recording the original
dominator for all blocks at the start of the pass.
If we were to record just the basic block, that could change if the block is
split. We want to traverse the code in the body of the original dominator,
whatever block it ends up in. To make this easy to track, we not save the
terminator instruction to represent the original dominator.
Fixes#2745
When a phi candidate is marked as trivial, we are suppose to update all
of its uses to the reference the value that it is being folded to.
However, the code updates the uses misses `defs_at_block_`. So at a
later time, the id for the trivial phi can reemerge.
Fixes#2744
* Bindless Instrument: Make init check depend solely on input_init_enabled
Previously was dependent on presense of descriptor_indexing extension
in SPIR-V, but this missed some cases. Tests updated to refect this new
policy.
* Fix format.
This change refactors all storage class validation for atomics
to reflect the similar refactoring in the specification.
It is currently not possible to write a test for the check
rejecting Generic in an OpenCL 1.2 environment as the required
GenericPointer capability isn't allowed there. I've decided
to keep the check nonetheless to guard against the capability
becoming available without the rules for atomics being updated.
The ID changes in existing tests aren't ideal but introducing
names drags in a substantial refactoring of this file.
Contributes to #2595.
Signed-off-by: Kevin Petit <kevin.petit@arm.com>
* Fix bug in merge return
The merge return pass seems to assume that the only new edges in the cfg
are from return block to merge blocks. However, it is possible that a
merge block branches to a merge block when it did not before.
This change add a new variable to track all of the new edges. It also
renames some other variables and cleans us the code to make it a bit
easier to read.
Fixes#2702.
Dead branch elimination needs to know about the constructs that a block is contained it when determining what to do with its merge instruction. We currently fold branches in block as we see them, which is parent constructs before their children. This causes the struct cfg analysis to crash because it tries to get the parent construct for a block after the parent has been folded.
This can be fixed by folding the branch of the children before the parents.
Fixes#2667.
There are a couple spots where we are not looking at decorations when we should.
1. Value numbering is suppose to assign a different value number to ids if they have different decorations. However that is not being done for OpCopyObject and OpPhi.
1. Instruction simplification is propagating OpCopyObject instruction without checking for decorations. It should only do that if no decorations are being lost.
Add a new function to the decoration manager to check if the decorations of one id are a subset of the decorations of another.
Fixes#2715.
Fixes#2669
* Check capabilities when validating variables
* validate load and store types
* Constant check
* Don't checks pointers for stores, constants and loads
* Validate composite instructions
* Validate conversions for 8- and 16-bit limited types
* Unified tests and expanded them
* Disallow OpCopyMemory
* new tests and update old tests
Adds to spirv-fuzz the option to shrink a sequence of transformations
that lead to an interesting binary to be generated, to find a smaller
sub-sequence of transformations that still lead to an interesting (but
hopefully simpler) binary being generated. The notion of what counts
as "interesting" comes from a user-provided script, the
"interestingness function", similar to the way the spirv-reduce tool
works. The shrinking process will give up after a maximum number of
steps, which can be configured on the command line.
Tests for the combination of fuzzing and shrinking are included, using
a variety of interestingness functions.
Inlining does not inline functions that have a single return that is in a loop. This is because the return cannot be replaced by a branch outside of the loop easily. Merge return knows how to rewrite the function so the return is replaced by a branch.
Fixes#2038.
It is illegal to inline an OpKill instruction into a continue construct because the continue header will no longer dominate the backedge.
This commit adds a check for this, and does not inline.
If we still want to be able to inline a function that contains an OpKill, we can add a new pass that will wrap OpKill instructions into its own function with just the single instruction.
I do not believe that this is a common case right now, so I will not do that yet.
Fixes#2433.
When working on descriptor indexing validation for compute shaders, the
gl_GlobalInvocationID builtin was being loaded as uint which would cause
compute shaders instrumented by the bindless check pass to have:
%83 = OpLoad %uint %gl_GlobalInvocationID
%84 = OpCompositeExtract %uint %83 0
%85 = OpCompositeExtract %uint %83 1
%86 = OpCompositeExtract %uint %83 2
which results in validation failures:
error: line 127: Reached non-composite type while indexes still remain
to be traversed.
%84 = OpCompositeExtract %uint %83 0
for trying to extract a uint from a uint.
Fixes#2695. Allowing unreachable blocks to be moved can lead to an
unreachable block A getting placed after an unreachable successor B,
which is a problem if B uses ids that A generates.
* Represent uniform facts via descriptor set and binding.
Previously uniform facts were expressed with resepect to the id of a
uniform variable. Describing them with respect to a descriptor set
and binding is more convenient from the point of view of expressing
facts about a shader without requiring analysis of its SPIR-V.
* Fix equality testing for uniform buffer element descriptors.
The equality test now checks that the lengths of the index vectors
match. Added a test that exposes the previous omission.
Adds a new transformation that can replace a constant with a uniform known to have the same value, and adds a fuzzer pass that (a) replaces a boolean with a comparison of literals (e.g. replacing "true" with "42 > 24"), and then (b) obfuscates the literals appearing in this comparison by replacing them with identically-valued uniforms, if available.
The fuzzer_replayer test file has also been updated to allow initial facts to be provided, and to do error checking of the status results returned by the fuzzer and replayer components.
* Can only be used with Vulkan memory model
* Can only be used with atomics
* Bit setting must match for compare exchange opcodes
* Updated memory semantics checks to allow constant instructions
generally with CooperativeMatrixNV
The replayer takes an existing sequence of transformations and applies
them to a module. Replaying a sequence of transformations that were
obtained via fuzzing should lead to an identical module to the module
that was fuzzed. Tests have been added to check for this.
Adds a new (and first) kind of fact to the fact manager, which is that
a specific uniform value is guaranteed to be equal to a specific
constant. The point of this is that such information (if known to be
true by some external source) can be used by spirv-fuzz to transform
the module in interesting ways that a static compiler cannot reverse
via compile-time analysis.
This change introduces protobuf messages for the fact, and adds
capabilities to the fact manager to store this kind of fact and
provide information about it.
The transformation can, for example, replace "true" with "12.0 > 6.0",
if constants for those floating-point values are available.
This introduces a new 'id use descriptor' structure, which provides a
way to describe a particular use of an id, and which will be heavily
used in future transformations. Describing an id use is trivial if
the use occurs in an instruction that itself generates an id, but is
less straightforward if the id of interest is used by an instruction
such as OpStore that does not have a result id. The 'id use
descriptor' structure caters for such cases.
Also add a Builtin test generator variant that takes
capabilities and extensions.
Tests
- verify that the SMCountNV, SMIDNV, WarpsPerSMNV, and WarpIDNV Builtins are
accepted as Inputs in Vertex, Fragment, TessControl, TessEval, Geometry,
and Compute.
- verify that the SMCountNV, SMIDNV, WarpsPerSMNV, and WarpIDNV Builtins are
accepted as Inputs in MeshNV and TaskNV shaders.
- verify that the SMCountNV, SMIDNV, WarpsPerSMNV, and WarpIDNV Builtins are
accepted as Inputs in the 6 ray tracing stages
- verify that the SMCountNV, SMIDNV, WarpsPerSMNV, and WarpIDNV Builtins are
NOT accepted as Outputs.
- verify that the SMCountNV, SMIDNV, WarpsPerSMNV, and WarpIDNV Builtins are
NOT accepted as non-scalar integers (f32, uvec3)
- verify that the SMCountNV, SMIDNV, WarpsPerSMNV, and WarpIDNV Builtins are
NOT accepted as non-32-bit integers (u64)
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.
When it's an OpConstant or OpSpecConstant, then the literal
values are compared. If the OpSpecConstant also has a SpecId
decoration, then that's also compared.
Otherwise, it's an OpSpecConstantOp and we only compare the
ID of the OpSpecConstantOp instruction itself.
Fixes#2649
This new pass adds some basic ingredients to a module on which future
passes are likely to depend, such as boolean constants and some
specfic integer and floating-point values. This is not a fuzzer pass
in the true sense in that it does not employ randomization, but it
makes sense to define it as a fuzzer pass since it is the first of a
number of transformations passes that the fuzzer will run on a module.
* Types: Avoid comparing IDs for in Type::IsSameImpl
When linking, we end up with duplicate types for imported and exported
types, that needs to be removed. The current code would reject valid
import/export pairs of symbols due to IDs mismatch, even if the types or
constants behind those ID were the same.
Enabled remaining type_match_test
Fixes#2442
New version has additional word in stage-specific section. Also
some changes in content for tesselation and compute shaders. Either
version can be invoked at pass creation. This is done to ease integration
and updating of validation layers. Version 1 is deprecated and eventually
will go away.
Also sneaking in fix to version 1 compute shaders.
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.
* Handle nested breaks from switches.
There was a recent decision made to allow branches to the merge node of
a switch even if the switch is not the first enclosing construct. They
can be generated by glslang from break statements in switches.
Dead branch elimination seems to be the only optimization that will
break because of this change, so I will update that optimizations.
The change made are:
- Track switches in structured cfg analysis.
- In Dead branch elimination:
- Look for nested breaks that will require a switch instruction.
- Rewrite, but don't delete, switchs that are required even if it
could be replaced by an unconditional branch.
- When looking for the first break, consider the merge of a switch
as well.
See #2612.
* Fix variable names and comments.
* Add tests for the struct cfg analysis and switches.
* Fix typos in comments.
This adds a number of tests that check that all types will match to
identically written clones during linking, including nearly every Type
and some combinations (e.g. Functions of Arrays of Floats). Intent is
for use with https://github.com/KhronosGroup/SPIRV-Tools/pull/2580,
however that PR focuses on issues with TypeArray whereas these tests are
(more) comprehensive and test more subtle (and possibly incorrect)
cases.
A number of these tests fail, many are fixed by the aforementioned PR.
Some additional tests involving TypeForwardPointer are currently
disabled as they cause assertion failures.
Fixes#2604
* Allow selection constructs to branch to the nearest selection merge
whose header is terminated by an OpSwitch
* Cleanup break and continue checks generally
* add tests
In order to try to reduce code duplication and to be able
to fold more cases, we want to use the instruction folder
when folding an OpSpecConstantOp with constant operands.
A couple other changes are need to make this work. First
GetDefiningInstruction| in the constant manager is able
to handle |type_id| being logically equivalent to another
type, so we updated the interface, and removed the assert.
Some tests were also updated because we not generate
better code because constants are not duplicated as much
as before.
No need for new tests. The functionality of the instruction folder is
already tested. There are tests check that the instruction folder is
being used correctly for OpCompositeExtract and OpVectorShuffle in the
existing test cases.
Fixes#2585.
It is currently not possible to use an Image Format that is
not Unknown without requiring a capability forbidden by the
OpenCL environment. As such the validation of Image Format
currently leans on capability validation entirely.
Fixes#2592.
Signed-off-by: Kevin Petit <kevin.petit@arm.com>
Validate structured exits from constructs
* Add checks that exits from a construct are valid
* Add Construct::IsStructuredExit()
* uses specific rules for each type of construct
* Added a test and check for #2213
* Adding tests for bad loop and continue exits
* Fix identification of continue block that prevented some selections
from having any blocks
* Update memory model support for SPIR-V 1.4
Fixes#2552
* Upgrade memory model now supports two memory access operands for
OpCopyMemory*
* in all cases the pass will first generate two operands by either
adding them or copying
* updates accounts for multiple operands
* tests
There is a case where sroa is not handling id overflow gracefully. It
is handled and an error message is output when the ids overflow.
Fixes https://crbug.com/961030.
* Make pointers to logically matching types interchangeable with option.
DXC will be generating code where the function parameters will be a more
generic type that the actual parameter. They should be logically
matching and the decorations of the actual parameter must be a superset
of the decorations of the formal parameter.
We want to accept this code with an options so that spirv-opt can then
inline and fix the type mismatch. We will accept this under a new
options `--before-hlsl-legalization`.
The new option will also imply `relax-logical-pointer` so that HLSL
frontends will need to use just the one more generic option.
Moved the |LogicallyMatches| to the validation state to make it
available in more places. Also added a parameter to have it check the
decorations. I did not do a separate function for the decorations
because checking the decorations involves making sure the types
logically match anyway.
Fixes#2535
* Use grammar last version
Fixes#2560
* Parse last version and use it in checks
* Update grammar header generation
* Fix NonWritable tests
* Fix check and add specific tests
Fixes#2555
* Fix a bug in validation where interfaces were considered non-unique
between different entry points targeting the same function
* added a test
* Update private to local pass to remove localized private variables
from entry point interfaces
* added tests
Fixes#2551
* Add support for 1.4 entry point interface lists
* only input and output variables are automatically live
* can clean up interfaces after DCE
* added tests
* allow opt tests to specify a target environment
* SPIR-V 1.4 headers, add SPV_ENV_UNIVERSAL_1_4
* Support --target-env spv1.4 in help for command line tools
* Support asm/dis of UniformId decoration
* Validate UniformId decoration
* Fix version check on instructions and operands
Also register decorations used with OpDecorateId
* Extension lists can differ between enums that match
Example: SubgroupMaskEq vs SubgroupMaskEqKHR
* Validate scope value for Uniform decoration, for SPIR-V 1.4
* More unioning of exts
* Preserve grammar order within an enum value
* 1.4: Validate OpSelect over composites
* Tools default to 1.4
* Add asm/dis test for OpCopyLogical
* 1.4: asm/dis tests for PtrEqual, PtrNotEqual, PtrDiff
* Basic asm/Dis test for OpCopyMemory
* Test asm/dis OpCopyMemory with 2-memory access
Add asm/dis tests for OpCopyMemorySized
Requires grammar update to add second optional memory access operand
to OpCopyMemory and OpCopyMemorySized
* Validate one or two memory accesses on OpCopyMemory*
* Check av/vis on CopyMemory source and target memory access
This is a proposed rule. See
https://gitlab.khronos.org/spirv/SPIR-V/issues/413
* Validate operation for OpSpecConstantOp
* Validate NonWritable decoration
Also permit NonWritable on members of UBO and SSBO.
* SPIR-V 1.4: NonWrtiable can decorate Function and Private vars
* Update optimizer CLI tests for SPIR-V 1.4
* Testing tools: Give expected SPIR-V version in message
* SPIR-V 1.4 validation for entry point interfaces
* Allow only unique interfaces
* Allow all global variables
* Check that all statically used global variables are listed
* new tests
* Add validation fixture CompileFailure
* Add 1.4 validation for pointer comparisons
* New tests
* Validate with image operands SignExtend, ZeroExtend
Since we don't actually know the image texel format, we can't fully
validate. We need more context.
But we can make sure we allow the new image operands in known-good
cases.
* Validate OpCopyLogical
* Recursively checks subtypes
* new tests
* Add SPIR-V 1.4 tests for NoSignedWrap, NoUnsignedWrap
* Allow scalar conditions in 1.4 with OpSelect
* Allows scalar conditions with vector operands
* new tests
* Validate uniform id scope as an execution scope
* Validate the values of memory and execution scopes are valid scope
values
* new test
* Remove SPIR-V 1.4 Vulkan 1.0 environment
* SPIR-V 1.4 requires Vulkan 1.1
* FIX: include string for spvLog
* FIX: validate nonwritable
* FIX: test case suite for member decorate string
* FIX: test case for hlsl functionality1
* Validation test fixture: ease debugging
* Use binary version for SPIR-V 1.4 specific features
* Switch checks based on the SPIR-V version from the target environment
to instead use the version from the binary
* Moved header parsing into the ValidationState_t constructor (where
version based features are set)
* Added new versions of tests that assemble a 1.3 binary and validate a
1.4 environment
* Fix test for update to SPIR-V 1.4 headers
* Fix formatting
* Ext inst lookup: Add Vulkan 1.1 env with SPIR-V 1.4
* Update spirv-val help
* Operand version checks should use module version
Use the module version instead of the target environment version.
* Fix comment about two-access form of OpCopyMemory
Add functionality to fix-storage-class so that it can fix up mismatched
data types for pointers as well.
Fixes bugs in when fixing up storage class.
Move GenerateCopy to the Pass class to be reused.
The spirv-opt change for #2535.
* Change implementation of post order CFG traversal
It seems like the recursion is going very deep, and causing some problem
is particular situations. I've reimplemented the CFG post order
traversal to not use recursion.
Fixes#2539.
