This enables performing several reductions in parallel, each smaller
than the size of the subgroup.
One potential application is flash attention with subgroup-wide matrix
multiplication and reduction combined in one kernel. The multiplication
operation requires a 2D matrix to be distributed over the lanes of the
subgroup, which then constrains the shape the following reduction can
have if we want to keep data in registers.
- Replace hand-written parser/printer with auto-generated assembly
format.
- Remove implicit `gpu.module_end` terminator and use the `NoTerminator`
trait instead. (Same as `builtin.module`.)
- Turn the region into a graph region. (Same as `builtin.module`.)
Each vector element is reduced independently, which is a form of
multi-reduction.
The plan is to allow for gradual lowering of multi-reduction that
results in fewer `gpu.shuffle` ops at the end:
1d `vector.multi_reduction` --> 1d `gpu.subgroup_reduce` --> smaller 1d
`gpu.subgroup_reduce` --> packed `gpu.shuffle` over i32
For example we can perform 2 independent f16 reductions with a series of
`gpu.shuffles` over i32, reducing the final number of `gpu.shuffles` by 2x.
This is to avoid confusion when dealing with reduction/combining kinds.
For example, see a recent PR comment:
https://github.com/llvm/llvm-project/pull/75846#discussion_r1430722175.
Previously, they were picked to mostly mirror the names of the llvm
vector reduction intrinsics:
https://llvm.org/docs/LangRef.html#llvm-vector-reduce-fmin-intrinsic. In
isolation, it was not clear if `<maxf>` has `arith.maxnumf` or
`arith.maximumf` semantics. The new reduction kind names map 1:1 to
arith ops, which makes it easier to tell/look up their semantics.
Because both the vector and the gpu dialect depend on the arith dialect,
it's more natural to align names with those in arith than with the
lowering to llvm intrinsics.
Issue: https://github.com/llvm/llvm-project/issues/72354
The motivation for this change is explained in
https://github.com/llvm/llvm-project/issues/72354.
Before this change, we could not tell between signed/unsigned
minimum/maximum and NaN treatment for floating point values.
The mapping of old reduction operations to the new ones is as follows:
* `min` --> `minsi` for ints, `minf` for floats
* `max` --> `maxsi` for ints, `maxf` for floats
New reduction kinds not represented in the old enum: `minui`, `maxui`,
`minimumf`, `maximumf`.
As a next step, I would like to have a common definition of combining
kinds used by the `vector` and `gpu` dialects. Separately, the GPU to
SPIR-V lowering does not yet properly handle zero and NaN values -- the
behavior of floating point min/max group reductions is not specified by
the SPIR-V spec, see https://github.com/llvm/llvm-project/issues/73459.
Issue: https://github.com/llvm/llvm-project/issues/72354
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
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
We use `use64bitIndex` in the option to decide the target device
address bitwidth. This makes it consistent with index type
conversion too.
Reviewed By: kuhar
Differential Revision: https://reviews.llvm.org/D144827
Vulkan requires GPU processor ID/count builtin variables to be
32-bit scalar or vector for all the cases. Similarly there
are special requirements for OpenCL. We need to make sure those
rules are respected when converting using 64bit for index.
Reviewed By: kuhar
Differential Revision: https://reviews.llvm.org/D144819
This is part of an effort to migrate from llvm::Optional to
std::optional. 22426110c5 changed the way mlir-tblgen generates .inc
files, emitting std::optional when an Optional attribute is specified in
a .td file. It also changed several .td files hard-coding llvm::Optional
to use std::optional. However, the patch excluded a few .td files in
SPIRV and Bufferization hard-coding llvm::Optional. This patch fixes
that defect, and after this patch, references to llvm::Optional in .cpp
and .h files can be replaced mechanically.
See also: https://discourse.llvm.org/t/deprecating-llvm-optional-x-hasvalue-getvalue-getvalueor/63716
Signed-off-by: Ramkumar Ramachandra <r@artagnon.com>
Differential Revision: https://reviews.llvm.org/D140329
Reland D139447, D139471 With flang actually working
- FunctionOpInterface: make get/setFunctionType interface methods
This patch removes the concept of a `function_type`-named type attribute
as a requirement for implementors of FunctionOpInterface. Instead, this
type should be provided through two interface methods, `getFunctionType`
and `setFunctionTypeAttr` (*Attr because functions may use different
concrete function types), which should be automatically implemented by
ODS for ops that define a `$function_type` attribute.
This also allows FunctionOpInterface to materialize function types if
they don't carry them in an attribute, for example.
Importantly, all the function "helper" still accept an attribute name to
use in parsing and printing functions, for example.
- FunctionOpInterface: arg and result attrs dispatch to interface
This patch removes the `arg_attrs` and `res_attrs` named attributes as a
requirement for FunctionOpInterface and replaces them with interface
methods for the getters, setters, and removers of the relevent
attributes. This allows operations to use their own storage for the
argument and result attributes.
Reviewed By: jpienaar
Differential Revision: https://reviews.llvm.org/D139736
This patch removes the concept of a `function_type`-named type attribute
as a requirement for implementors of FunctionOpInterface. Instead, this
type should be provided through two interface methods, `getFunctionType`
and `setFunctionTypeAttr` (*Attr because functions may use different
concrete function types), which should be automatically implemented by
ODS for ops that define a `$function_type` attribute.
This also allows FunctionOpInterface to materialize function types if
they don't carry them in an attribute, for example.
Importantly, all the function "helper" still accept an attribute name to
use in parsing and printing functions, for example.
Reviewed By: rriddle, lattner
Differential Revision: https://reviews.llvm.org/D139447
This patch mechanically replaces None with std::nullopt where the
compiler would warn if None were deprecated. The intent is to reduce
the amount of manual work required in migrating from Optional to
std::optional.
This is part of an effort to migrate from llvm::Optional to
std::optional:
https://discourse.llvm.org/t/deprecating-llvm-optional-x-hasvalue-getvalue-getvalueor/63716
This commit extends the `ResourceLimitsAttr` to support specifying
a minimal and maximal subgroup size, and extends `EntryPointABIAttr`
to support specifying the requested subgroup size. This is possible
now in Vulkan with the VK_EXT_subgroup_size_control extension.
For OpenCL it's possible to use the `SubgroupSize` execution mode
directly.
Reviewed By: ThomasRaoux
Differential Revision: https://reviews.llvm.org/D138962
This allows for incrementally updating the old API usages without
needing to update everything at once. These will be left on Both
for a little bit and then flipped to prefixed when all APIs have been
updated.
Differential Revision: https://reviews.llvm.org/D134386
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
This removes any potential confusion with the `getType` accessors
which correspond to SSA results of an operation, and makes it
clear what the intent is (i.e. to represent the type of the function).
Differential Revision: https://reviews.llvm.org/D121762
* It doesn't required by OpenCL/Intel Level Zero and can be set programmatically.
* Add GPU to spirv lowering in case when attribute is not present.
* Set higher benefit to WorkGroupSizeConversion pattern so it will always try to lower first from the attribute.
Differential Revision: https://reviews.llvm.org/D120399
This commit refactors the FunctionLike trait into an interface (FunctionOpInterface).
FunctionLike as it is today is already a pseudo-interface, with many users checking the
presence of the trait and then manually into functionality implemented in the
function_like_impl namespace. By transitioning to an interface, these accesses are much
cleaner (ideally with no direct calls to the impl namespace outside of the implementation
of the derived function operations, e.g. for parsing/printing utilities).
I've tried to maintain as much compatability with the current state as possible, while
also trying to clean up as much of the cruft as possible. The general migration plan for
current users of FunctionLike is as follows:
* function_like_impl -> function_interface_impl
Realistically most user calls should remove references to functions within this namespace
outside of a vary narrow set (e.g. parsing/printing utilities). Calls to the attribute name
accessors should be migrated to the `FunctionOpInterface::` equivalent, most everything
else should be updated to be driven through an instance of the interface.
* OpTrait::FunctionLike -> FunctionOpInterface
`hasTrait` checks will need to be moved to isa, along with the other various Trait vs
Interface API differences.
* populateFunctionLikeTypeConversionPattern -> populateFunctionOpInterfaceTypeConversionPattern
Fixes#52917
Differential Revision: https://reviews.llvm.org/D117272
NamedAttribute is currently represented as an std::pair, but this
creates an extremely clunky .first/.second API. This commit
converts it to a class, with better accessors (getName/getValue)
and also opens the door for more convenient API in the future.
Differential Revision: https://reviews.llvm.org/D113956
There are several aspects of the API that either aren't easy to use, or are
deceptively easy to do the wrong thing. The main change of this commit
is to remove all of the `getValue<T>`/`getFlatValue<T>` from ElementsAttr
and instead provide operator[] methods on the ranges returned by
`getValues<T>`. This provides a much more convenient API for the value
ranges. It also removes the easy-to-be-inefficient nature of
getValue/getFlatValue, which under the hood would construct a new range for
the type `T`. Constructing a range is not necessarily cheap in all cases, and
could lead to very poor performance if used within a loop; i.e. if you were to
naively write something like:
```
DenseElementsAttr attr = ...;
for (int i = 0; i < size; ++i) {
// We are internally rebuilding the APFloat value range on each iteration!!
APFloat it = attr.getFlatValue<APFloat>(i);
}
```
Differential Revision: https://reviews.llvm.org/D113229
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
- Fixed symbol insertion into `symNameToModuleMap`. Insertion
needs to happen whether symbols are renamed or not.
- Added check for the VCE triple and avoid dropping it.
- Disabled function deduplication. It requires more careful
rules. Right now it can remove different functions.
- Added tests for symbol rename listener.
- And some other code/comment cleanups.
Reviewed By: ergawy
Differential Revision: https://reviews.llvm.org/D106886
This allows us to remove the `spv.mlir.endmodule` op and
all the code associated with it.
Along the way, tightened the APIs for `spv.module` a bit
by removing some aliases. Now we use `getRegion` to get
the only region, and `getBody` to get the region's only
block.
Reviewed By: mravishankar, hanchung
Differential Revision: https://reviews.llvm.org/D103265
The current design uses a unique entry for each argument/result attribute, with the name of the entry being something like "arg0". This provides for a somewhat sparse design, but ends up being much more expensive (from a runtime perspective) in-practice. The design requires building a string every time we lookup the dictionary for a specific arg/result, and also requires N attribute lookups when collecting all of the arg/result attribute dictionaries.
This revision restructures the design to instead have an ArrayAttr that contains all of the attribute dictionaries for arguments and another for results. This design reduces the number of attribute name lookups to 1, and allows for O(1) lookup for individual element dictionaries. The major downside is that we can end up with larger memory usage, as the ArrayAttr contains an entry for each element even if that element has no attributes. If the memory usage becomes too problematic, we can experiment with a more sparse structure that still provides a lot of the wins in this revision.
This dropped the compilation time of a somewhat large TensorFlow model from ~650 seconds to ~400 seconds.
Differential Revision: https://reviews.llvm.org/D102035
This commit add utility functions for creating push constant
storage variable and loading values from it.
Along the way, performs some clean up:
* Deleted `setABIAttrs`, which is just a 4-liner function
with one user.
* Moved `SPIRVConverstionTarget` into `mlir` namespace,
to be consistent with `SPIRVTypeConverter` and
`LLVMConversionTarget`.
Reviewed By: mravishankar
Differential Revision: https://reviews.llvm.org/D99725
This doesn't change APIs, this just cleans up the many in-tree uses of these
names to use the new preferred names. We'll keep the old names around for a
couple weeks to help transitions.
Differential Revision: https://reviews.llvm.org/D99127