Investigate the lowering of MemRef Load/Store ops and implement
additional folding of created ops
Aims to improve readability of generated lowered SPIR-V code.
Part of work llvm#70704
The SPIR-V spec requires that memory accesses to
`PhysicalStorageBuffer`s are annotated with appropriate alignment
attributes [1]. Calculate these based on memref alignment attributes or
scalar type sizes.
[1] Otherwise spirv-val complains:
```
[VULKAN] ! Validation Error: [ VUID-VkShaderModuleCreateInfo-pCode-01379 ] | MessageID = 0x2a1bf17f | SPIR-V module not valid: [VUID-StandaloneSpirv-PhysicalStorageBuffer64-04708] Memory accesses with PhysicalStorageBuffer must use Aligned.
%48 = OpLoad %float %47
```
Support environments where logical types do not necessarily correspond to allowed storage access types.
Also make pattern match failures more descriptive.
Reviewed By: antiagainst
Differential Revision: https://reviews.llvm.org/D159386
We need to use the converted index type for index offset calculation
logic; not the target bitwidth, which is typically 32-bit.
Reviewed By: kuhar
Differential Revision: https://reviews.llvm.org/D158482
ConversionPatterns do not (and should not) modify the type converter that they are using.
* Make `ConversionPattern::typeConverter` const.
* Make member functions of the `LLVMTypeConverter` const.
* Conversion patterns take a const type converter.
* Various helper functions (that are called from patterns) now also take a const type converter.
Differential Revision: https://reviews.llvm.org/D157601
For kernel SPIR-V, we are lowering memref to bare pointers, so reinterpret can be lowered to pointer, adjusted by offset value.
Differential Revision: https://reviews.llvm.org/D155011
In SPIR-V, the capabilities for storage and compute are separate.
We have good handling of the storage side in general via MemRef
type conversion and various `memref` dialect ops.
Once the value was loaded properly, if the compute capability is
supported directly, we don't need to emulate like the storage side
with int32. However, we do need to make sure casting ops are
properly inserted to chain the flow to go back to the original
bitwidth.
Right now that is done in the each individual pattern directly,
which put lots of pressure that shouldn't be on the patterns and
causes duplication and trickiness w.r.t. capability check and such.
Instead, we should handle such casting within the SPIR-V conversion
framework using `addSourceMaterialization`, where we can check with
the target environment to make sure the corresponding compute
capability is allowed and then we can materialize and SPIR-V casting
op.
Along the way, we can drop all the duplicated cast materialization
registration in various places.
Reviewed By: kuhar
Differential Revision: https://reviews.llvm.org/D155118
The MLIR classes Type/Attribute/Operation/Op/Value support
cast/dyn_cast/isa/dyn_cast_or_null functionality through llvm's doCast
functionality in addition to defining methods with the same name.
This change begins the migration of uses of the method to the
corresponding function call as has been decided as more consistent.
Note that there still exist classes that only define methods directly,
such as AffineExpr, and this does not include work currently to support
a functional cast/isa call.
Caveats include:
- This clang-tidy script probably has more problems.
- This only touches C++ code, so nothing that is being generated.
Context:
- https://mlir.llvm.org/deprecation/ at "Use the free function variants
for dyn_cast/cast/isa/…"
- Original discussion at https://discourse.llvm.org/t/preferred-casting-style-going-forward/68443
Implementation:
This first patch was created with the following steps. The intention is
to only do automated changes at first, so I waste less time if it's
reverted, and so the first mass change is more clear as an example to
other teams that will need to follow similar steps.
Steps are described per line, as comments are removed by git:
0. Retrieve the change from the following to build clang-tidy with an
additional check:
https://github.com/llvm/llvm-project/compare/main...tpopp:llvm-project:tidy-cast-check
1. Build clang-tidy
2. Run clang-tidy over your entire codebase while disabling all checks
and enabling the one relevant one. Run on all header files also.
3. Delete .inc files that were also modified, so the next build rebuilds
them to a pure state.
4. Some changes have been deleted for the following reasons:
- Some files had a variable also named cast
- Some files had not included a header file that defines the cast
functions
- Some files are definitions of the classes that have the casting
methods, so the code still refers to the method instead of the
function without adding a prefix or removing the method declaration
at the same time.
```
ninja -C $BUILD_DIR clang-tidy
run-clang-tidy -clang-tidy-binary=$BUILD_DIR/bin/clang-tidy -checks='-*,misc-cast-functions'\
-header-filter=mlir/ mlir/* -fix
rm -rf $BUILD_DIR/tools/mlir/**/*.inc
git restore mlir/lib/IR mlir/lib/Dialect/DLTI/DLTI.cpp\
mlir/lib/Dialect/Complex/IR/ComplexDialect.cpp\
mlir/lib/**/IR/\
mlir/lib/Dialect/SparseTensor/Transforms/SparseVectorization.cpp\
mlir/lib/Dialect/Vector/Transforms/LowerVectorMultiReduction.cpp\
mlir/test/lib/Dialect/Test/TestTypes.cpp\
mlir/test/lib/Dialect/Transform/TestTransformDialectExtension.cpp\
mlir/test/lib/Dialect/Test/TestAttributes.cpp\
mlir/unittests/TableGen/EnumsGenTest.cpp\
mlir/test/python/lib/PythonTestCAPI.cpp\
mlir/include/mlir/IR/
```
Differential Revision: https://reviews.llvm.org/D150123
Add a new helper function for the type converter that takes care of
casting to the target type.
This is to avoid bugs where an incorrect cast function is used after
type conversion, e.g., `dyn_cast` or `cast`. These are not guaranteed to
work when type conversion fails, or when type conversion succeeds but
the provided type converted returned a type that a conversion pattern
did not expect.
I saw this being an issue in some SPIR-V passes and in mlir-hlo.
Exercise the new function in a couple of passes. As a side-effect, this
also made the code more concise.
Reviewed By: rriddle, mehdi_amini
Differential Revision: https://reviews.llvm.org/D148725
Address space casts are present in common MLIR targets (LLVM, SPIRV).
Some planned rewrites (such as one of the potential fixes to the fact
that the AMDGPU backend requires alloca() to live in address space 5 /
the GPU private memory space) may require such casts to be inserted
into MLIR code, where those address spaces could be represented by
arbitrary memory space attributes.
Therefore, we define memref.memory_space_cast and its lowerings.
Depends on D141293
Reviewed By: ftynse
Differential Revision: https://reviews.llvm.org/D141148
-Add awareness to Kernel vs Shader capability for memref to SPIR-V
lowering.
-Add lowering using spv.PtrAccessChain for Kernel capability.
-Enable lowering from scalar pointee types for kernel capabilities.
Reviewed By: antiagainst
Differential Revision: https://reviews.llvm.org/D132714
This commit moves MemRef memory space to SPIR-V storage class
conversion out of the main SPIR-V type converter. Now the mapping
should happen as a prelimiary step before performing the final
conversion to SPIR-V. Flows are expect to write their own memory
space mappings like the `MapMemRefStorageClassPass` to handle
memory space mappings according to their needs.
This is needed because SPIR-V is serving multiple client APIs,
including Vulkan and OpenCL. Different client APIs might want
to use different storage classes for buffers in a particular
memory space, e.g., `StorageBuffer` for Vulkan vs. `CrossWorkgroup`
for OpenCL when converting the default 0 memory space. Hardcoding
a specific mapping makes that hard. While it's possible to embed
selection logic further inside the main type converter, it will
make the main type converter even complicated. So it's better to
separate the concerns, as mapping the memory space is really
concretizing the meaning of those numeric memory spaces in the
particular context of SPIR-V lowering.
Reviewed By: kuhar
Differential Revision: https://reviews.llvm.org/D131410
MemRef types now can carry an attribute to represent the memory
space. Still, upper layers in the compilation stack mostly use
nuemric values. They don't mean much (other than differentiating
separate memory domains) in MLIR's multi-level settings. Those
numeric memory space inside MemRef types need to be translated
into concrete SPIR-V storage classes during lowering to pin down
to concrete memory types.
Thus far we have been hardcoding an arbitrary mapping from memory
space to storage class for converting MemRef types. This works fine
for only targeting Vulkan; it falls apart if we want to target other
SPIR-V consumers like OpenCL, as different consumers might want
different storage classes for the buffer/variable of the same
lifetime. For example, StorageClass in Vulkan vs. CrossWorkgroup
in OpenCL.
So putting up a new pass to let the user to control how to map
MemRef memory spaces into SPIR-V storage classes. This provides
more flexibility and can address the awkwardness in the current
SPIR-V type converter. This pass should be the prelimiary step
towards lowering MemRef related types/ops into SPIR-V.
Reviewed By: mravishankar
Differential Revision: https://reviews.llvm.org/D130317
This has been a TODO for a long time, and it brings about many advantages (namely nice accessors, and less fragile code). The existing overloads that accept ArrayRef are now treated as deprecated and will be removed in a followup (after a small grace period). Most of the upstream MLIR usages have been fixed by this commit, the rest will be handled in a followup.
Differential Revision: https://reviews.llvm.org/D110293
If the source value to load is bool, and we have native storage
capability support for the source bitwidth, we still cannot directly
rewrite uses; we need to perform casting to bool first.
Reviewed By: hanchung
Differential Revision: https://reviews.llvm.org/D107119
If the source value to store is bool, and we have native storage
capability support for the target bitwidth, we still cannot directly
store; we need to perform casting to match the target memref
element's bitwidth.
Reviewed By: hanchung
Differential Revision: https://reviews.llvm.org/D107114