It has been resolved that statically out-of-bounds accesses are not
invalid in SPIR-V (they lead to undefind behaviour at runtime but
should not cause a module to be rejected during validation). This
change tolerates such accesses in donated code, clamping them in-bound
as part of making a function live-safe.
Fixes a bug where, while recursively adding id equation facts, a
reference to a set of id equations could be used after it had been
freed (due to equivalence classes of equations being merged).
The Sample argument of OpImageTexelPointer is sometimes required to be
a zero constant. It thus cannot be replaced with a synonym in
general. This change avoids replacing this argument with a synonym.
The fact manager maintains an equivalence relation on data descriptors
that tracks when one data descriptor could be used in place of
another. An algorithm to compute the closure of such facts allows
deducing new synonym facts from existing facts. E.g., for two 2D
vectors u and v it is known that u.x is synonymous with v.x and u.y is
synonymous with v.y, it can be deduced that u and v are synonymous.
The closure computation algorithm is very expensive if we get large
equivalence relations.
This change addresses this in three ways:
- The size of equivalence relations is reduced by limiting the extent
to which the components of a composite are recursively noted as
being equivalent, so that when we have large synonymous arrays we do
not record all array elements as being pairwise equivalent.
- When computing the closure of facts, equivalence classes above a
certain size are simply skipped (which can lead to missed facts)
- The closure computation is performed less frequently - it is invoked
explicitly before fuzzer passes that will benefit from data synonym
facts. A new transformation is used to control its invocation, so
that fuzzing and replaying do not get out of sync.
The change also tidies up the order in which some getters are declared
in FuzzerContext.
Adds an extra condition on when a region can be outlined to avoid the
case where a region ends with a loop head but such that the loop's
continue target is in the region. (Outlining such a region would mean
that the loop merge is in the original function and the continue target
in the outlined function.)
The function outliner uses a struct to return ids that a region
generates and that are used outside that region. If these ids have
pointer type this would result in a struct with pointer members, which
leads to illegal loading from non-logical pointers if logical
addressing is used. This change bans that outlining possibility.
Provides support for runtime arrays in the code that traverses
composite types when checking applicability of transformations that
replace ids with synonyms.
Demotes the image storage class to Private during donation. Also
fixes an issue where instructions that depended on non-donated global
values would not be handled properly.
The SPIR-V data rules say that all uses of an OpSampledImage
instruction must be in the same block as the instruction, and highly
restrict those instructions that can consume the result id of an
OpSampledImage.
This adapts the transformations that split blocks and create synonyms
to avoid separating an OpSampledImage use from its definition, and to
avoid synonym-creation instructions such as OpCopyObject consuming an
OpSampledImage result id.
* Preserve debug info in eliminate-dead-functions
The elimination of dead functions makes OpFunction operand of
DebugFunction invalid. This commit replaces the operand with
DebugInfoNone.
* Handle more cases in dead member elim
- Rewrite composite insert and extract operations on SpecConstnatOp.
- Leaves assert for Access chain instructions, which are only allowed
for kernels.
- Other operations do not require any extra code will no longer cause an
assert.
Fixes#3284.
Fixes#3282.
The management of equation facts suffered from two problems:
(1) The processing of an equation fact required the data descriptors
used in the equation to be in canonical form. However, during
fact processing it can be deduced that certain data descriptors
are equivalent, causing their equivalence classes to be merged,
and that could cause previously canonical data descriptors to no
longer be canonical.
(2) Related to this, if id equations were known about a canonical data
descriptor dd1, and other id equations known about a different
canonical data descriptor dd2, the equation facts about these data
descriptors were not being merged in the event that dd1 and dd2
were deduced to be equivalent.
This changes solves (1) by not requiring equation facts to be in
canonical form while processing them, but instead always checking
whether (not necessary canonical) data descriptors are equivalent when
looking for corollaries of equation facts, rather than comparing them
using ==.
Problem (2) is solved by adding logic to merge sets of equations when
data descriptors are made equivalent.
In addition, the change also requires elements to be registered in an
equivalence relation before they can be made equivalent, rather than
being added (if not already present) at the point of being made
equivalent.
This change increases the extent to which arbitrary SPIR-V can be used
by the fuzzer pass that donates modules. It handles the case where
various ingredients (such as types, variables and particular
instructions) cannot be donated by omitting them, and then either
omitting their dependencies or replacing their dependencies with
alternative instructions.
The change pays particular attention to allowing code that manipulates
image types to be handled (by skipping anything image-specific).
(1) Runtime arrays are turned into fixed-size arrays, by turning
OpTypeRuntimeArray into OpTypeArray and uses of OpArrayLength into
uses of the constant used for the length of the fixed-size array.
(2) Atomic instructions are not donated, and uses of their results are
replaced with uses of constants of the result type.
The fuzzer pass that constructs composites had an issue where it would
regard isomorphic but distinct structs (similarly arrays) as being
interchangeable when constructing composites. This change fixes the
problem by relying less on the type manager.
To avoid problems where global and local variables of opaque or
runtime-sized types are added to a module, this change introduces the
notion of a 'basic type' -- a type made up from floats, ints, bools,
or vectors, matrices, structs and fixed-size arrays of basic types.
Added variables have to be of basic type.
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.
When DebugScope is given in SPIR-V, each instruction following the
DebugScope is from the lexical scope pointed by the DebugScope in
the high level language. We add DebugScope struction to keep the
scope information in Instruction class. When ir_loader loads
DebugScope/DebugNoScope, it keeps the scope information in
|last_dbg_scope_| and lets following instructions have that scope
information.
In terms of DebugDeclare/DebugValue, if it is in a function body
but outside of a basic block, we keep it in |debug_insts_in_header_|
of Function class. If it is in a basic block, we keep it as a normal
instruction i.e., in a instruction list of BasicBlock.
Create a pass to instrument OpDebugPrintf instructions. This pass replaces all OpDebugPrintf instructions with instructions to write a record containing the string id and the all specified values into a special printf output buffer (if space allows). This pass is designed to support the printf validation in the Vulkan validation layers.
Fixes#3210
In this PR, the classes that represent the toggle access chain
instruction transformation and fuzzer pass were implemented. This
transformation toggles the instructions OpAccessChain and
OpInBoundsAccessChain between them.
Fixes#3193.
This introduces a new fuzzer pass to add instructions to the module
that define equations, and support in the fact manager for recording
equation facts and deducing synonym facts from equation facts.
Initially the only equations that are supported involve OpIAdd,
OpISub, OpSNegate and OpLogicalNot, but there is scope for adding
support for equations over various other operators.
* Combine the extinst-name and extinst-output-base into one arg.
Some build systems such as Android blueprints require that the inputs
and outputs of generator scripts are all provided as arguments. These
two arguments to generate_language_headers.py are combined to form the
output path in the script. This change simply lets the user provide the
whole output path as an argument.
* Fix typo in build_defs.bzl and update Android.mk
According to SPV_AMD_shader_image_load_store_lod spec, Lod operand is
valid with OpImageRead, OpImageWrite, or OpImageSparseRead if the
extension is enabled.
This fixes a bug where the type id of a type instruction, rather than
its result id, was being used. It also favours using zero as the
return value when replacing an OpKill or OpUnreachable with a return
instruction, and adds a check that the donor module is valid when
doing module donation.
Fixes#3187.
This change adds a fuzzer pass that sprinkles access chain
instructions into a module at random. This allows other passes to
have a richer set of pointers available to them, in particular the
passes that add loads and stores.
Adds a fuzzer pass that inserts function calls into the module at
random. Calls from dead blocks can be arbitrary (so long as they do
not introduce recursion), while calls from other blocks can only be to
livesafe functions.
The change fixes some oversights in transformations to replace
constants with uniforms and to obfuscate constants which testing of
this fuzzer pass identified.
This change ensures that global and local variables donated from other
modules are always initialized at their declaration in the module
being transformed. This is to help limit issues related to undefined
behaviour that might arise due to accessing uninitialized memory.
The change also introduces some helper functions in fuzzer_util to
make it easier to find the pointee types of pointer types.
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.
Adds two new fuzzer passes to add variables to a module: one that adds
Private storage class global variables, another that adds Function
storage class local variables.
Adds a fuzzer pass that randomly adds vector and matrix types not
already present in the module, and randomly adds structs with random
field types and arrays with random base types and sizes. Other passes
will be able to create variables and ids using these types.
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.
This adds support for replacing TimeAMD with OpReadClockKHR. The scope
for OpReadClockKHR is fixed to be a subgroup because TimeAMD operates
only on subgroup.
* Implement constant folding for many transcendentals
This change adds support for folding of sin/cos/tan/asin/acos/atan,
exp/log/exp2/log2, sqrt, atan2 and pow.
The mechanism allows to use any C function to implement folding in the
future; for now I limited the actual additions to the most commonly used
intrinsics in the shaders.
Unary folder had to be tweaked to work with extended instructions - for
extended instructions, constants.size() == 2 and constants[0] ==
nullptr. This adjustment is similar to the one binary folder already
performs.
Fixes#1390.
* Fix Android build
On old versions of Android NDK, we don't get std::exp2/std::log2
because of partial C++11 support.
We do get ::exp2, but not ::log2 so we need to emulate that.
This change adds a new kind of fact to the fact manager, which records
when a variable (or pointer parameter) refers to an arbitrary value,
so that anything can be stored to it, without affecting the observable
behaviour of the module, and nothing can be guaranteed about values
loaded from it. Donated modules are the current source of such
variables, and other transformations, such as outlining, have been
adapted to propagate these facts appropriately.
This change allows the generator to (optionally and at random) make
the functions of a module "livesafe" during donation. This involves
introducing a loop limiter variable to each function and gating the
number of total loop iterations for the function using that variable.
It also involves eliminating OpKill and OpUnreachable instructions
(changing them to OpReturn/OpReturnValue), and clamping access chain
indices so that they are always in-bounds.
We must treat a branch to the merge node of a switch that is in the
header of a construct as a nested construced. The original merge
instruction is still needed in that case.
Fixes#3139
* If the header of the construct is also a merge block, jump to the
associated header instead of the immediate dominator
* prevents spurious failures from unrelated constructs
* new tests
This new API lets clients request a minimal spv_target_env value
that supports a given Vulkan and SPIR-V version, by a generic
numbering scheme (as already defined by Vulkan and SPIR-V specs).
This breaks a formal source dependency from Glslang to SPIRV-Tools.
When a new API is rolled out, such as Vulkan 1.2, Glslang currently
needs to reference a specific SPIRV-Tools enum by name.
* Allow OpExtInst for DebugInfo between secion 9 and 10
Fixes#3086
* Handle spirv-opt errors on DebugInfo Ext
* Add IR Loader test
* Fix ir loader bug
* Handle DebugFunction/DebugTypeMember forward reference
* Add test cases (forward reference to function)
* Support old DebugInfo extension
* Validate local debug info out of function
This change refactors some code for walking access chain indexes to
make it mirror the structure of other code (to improve readability in
the first instance and potentially enable a future refactoring to
extract common code), and fixes a problem related to module donation
and function types.
As explained in #3118, spirv-opt merge-blocks pass causes a
spirv-val error when an OpBranch has an OpLine in front of it.
OpLoopMerge
OpBranch ; Will be killed by merge-blocks pass
OpLabel ; Will be killed by merge-blocks pass
OpLine ; will be placed between OpLoopMerge and OpBranch - error!
OpBranch
To fix this issue, this commit moves line info of OpBranch to
OpLoopMerge.
Fixes#3118
This adds a new kind of fact to the fact manager that knows whether a
block is dead - i.e. guaranteed to be statically unreachable - and a
new transformation for adding a selection construct to a CFG that
conditionally branches to a fresh, dead block, such that the branch
will never be dynamically taken. Transformations that may create new
blocks ('split block' and 'outline function') are updated to propagate
dead block facts to newly-created blocks where appropriate. A fuzzer
pass randomly adds dead blocks to the module.
Future transformations will be able to exploit the fact that such
blocks are known to be dead.
This change adds a fuzzer pass that allows code from other SPIR-V
modules to be donated into the module under transformation. It also
changes the command-line options of the tools so that, in fuzzing
mode, a file must be specified that contains the names of available
donor modules.
* Clone opencl.debuginfo.100 grammar from debuginfo grammar
Update version number to 200 revision 2
* Apply content from OpenCL.DebugInfo.100 extension text
* Rename grammar file
* Support OpenCL.DebugInfo.100 extended instructions
Add support for prefixing operand type names, to disambiguate
them between different instruction sets.
* Add tests for OpenCL.DebugInfo.100
* Support lookup of OpenCL.DebugInfo.100 extinst
* Add tests for enum values
* Recognize 2017-2019 as copyright date range
* Android.mk: support OpenCL.DebugInfo.100 extended instruction set
Also, stop generating core instruction tables for non-unified1 versions
of the grammar.
* Imported entity operand type is concrete
* Bazel: Suppoort OpenCL.DebugInfo.100
* BUILD.gn: Support OpenCL.DebugInfo.100
In the context of SPIR-V 1.4 or higher, global variables cannot be
used by an instruction unless they are listed in the interface of all
entry points that might invoke the instruction. This change
conservatively adds new global variables to the interfaces of all
entry points (if the SPIR-V version is 1.4 or higher).
Issue #3111 notes that a more rigorous approach to entry point
interfaces could be taken in spirv-fuzz, which would allow being less
conservative here.
This change prevents the spirv-fuzz function outliner from outlining a
region that uses the result of an OpAccessChain not defined inside the
region. Such accesses were turning into parameters to the outlined
function, and the result of an OpAccessChain cannot be passed as a
function parameter according to the SPIR-V specification.
Add support for SPV_KHR_non_semantic_info
This entails a couple of changes:
- Allowing unknown OpExtInstImport that begin with the prefix `NonSemantic.`
- Allowing OpExtInst that reference any of those sets to contain unknown
ext inst instruction numbers, and assume the format is always a series of IDs
as guaranteed by the extension.
- Allowing those OpExtInst to appear in the types/variables/constants section.
- Not stripping OpString in the --strip-debug pass, since it may be referenced
by these non-semantic OpExtInsts.
- Stripping them instead in the --strip-reflect pass.
* Add adjacency validation of non-semantic OpExtInst
- We validate and test that OpExtInst cannot appear before or between
OpPhi instructions, or before/between OpFunctionParameter
instructions.
* Change non-semantic extinst type to single value
* Add helper function spvExtInstIsNonSemantic() which will check if the extinst
set is non-semantic or not, either the unknown generic value or any future
recognised non-semantic set.
* Add test of a complex non-semantic extinst
* Use DefUseManager in StripDebugInfoPass to strip some OpStrings
* Any OpString used by a non-semantic instruction cannot be stripped, all others
can so we search for uses to see if each string can be removed.
* We only do this if the non-semantic debug info extension is enabled, otherwise
all strings can be trivially removed.
* Silence -Winconsistent-missing-override in protobufs
* Make Instrumentation format version 2 the default (Step 1)
Add new interfaces without version number argument. Remove version 1
logic and tests. Version interfaces will be removed in step 2 after
layers have transitioned to new interface.
* Add error messages to InstrumentPass().
* Don't crash when folding construct of empty struct
An OpCompositeConstruct of an empty struct will be folded to a constant
under normal circumstances. However, if the id limit has been reached
and the constant cannot be generated, then other folding rules will be
tried.
These rules do not handle the case of an empty struct. We add allow it
to be handled.
Fixes http://crbug/1030194
* Changes based on the review.
A new transformation and associated fuzzer pass in spirv-fuzz that
selects single-entry single-exit control flow graph regions and for
each selected region outlines the region into a new function and
replaces the original region with a call to this function.
The passes that add dead breaks and continues suffer from the
challenge that a new control flow graph edge can change dominance
information, leading to the potenital for definitions to no longer
dominate their uses. The attempt at guarding against this was known
to be incomplete. This change calls on the SPIR-V validator to do the
necessary checking: in deciding whether adding such an edge would be
legitimate, we clone the module, add the edge, and use the validator
to check whether the transformed clone is valid.
This strategy is heavy-weight, and should be used sparingly, but seems
like a good option when the validity of transformations is intricate,
to avoid reimplementing swathes of validation logic in the fuzzer.
Fixes#2919.
