ssa-rewrite fails in `MemPass::GetPtr()` when the SPIR-V code contains
`OpLoad` for the result id of `OpConstantNull` because of the out of
index access for an operand to get the base address. This commit fixes
it.
Fixes#3344
In this PR, the classes that represent the adjust branch weights
transformation and fuzzer pass were implemented. This transformation
adjusts the branch weights of a OpBranchConditional instruction.
- No longer inline functions with early exits. Merge return can modify them so they can be inlined.
- Otherwise no functional change, should be just refactoring.
Extends the pass for removing unused instructions so that it can
remove global declarations (such as types and variables) that are only
used by decorations with which they are intimately connected, such as
descriptor set and binding decorations.
* Do merge return if the return is not at the end of the function.
We will remove the code in inlining to handle a return in the middle of
a function. To inline those functions, we need to run merge return to
move the return to the end of the function.
Generalizes the IsReadOnlyVariable() method, and related methods, so
that they can be used to ask whether pointer result ids are read-only.
Fixes#3324.
When moving blocks around, we ended up with a nullptr for a basic block,
and it was left in the list for a little bit. However, in that time, it
would end up being dereferenced while traversing the function.
To fix this, we delete it right away. This was found in an asan build
that runs our current tests. No new tests are needed, but I did add
extra check asan checks for our asan bot.
Many high-level languages like HLSL and GLSL generate termination
instructions such as return and branch from the actual part of the
high-level language code like return and if statements. This commit lets
IrLoader set `DebugScope` for termination instructions.
The outliner would outline regions ending with a loop header, making
the block containing the call to the outlined function serve as the
loop header. This, however, is incorrect in general, since the whole
outlined function -- rather than just the exit block for the region --
would end up getting called every time the loop would iterate.
This change restricts the outliner so that the last block in a region
cannot be a loop header.
We need an analysis for OpenCL.DebugInfo.100 extension instructions such
as a map between function id and its DebugFunction. This commit add an
analysis for it.
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.
This change increases the set of validator options that can be passed
to spirv-opt, to match those options that spirv-reduce and spirv-fuzz
accept. This is useful to still allow some validation, at the start
of and during optimisation, for SPIR-V modules that the strict
validator would reject.
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.
