`mbarrier` is a barrier created in shared memory that supports different flavors of synchronizing threads other than `__syncthreads`, for more information see below.
https://docs.nvidia.com/cuda/parallel-thread-execution/#parallel-synchronization-and-communication-instructions-mbarrier
This work adds initial Ops wrt `mbarrier` to nvgpu dialect.
First, it introduces to two types:
`mbarrier.barrier` that is barrier object in shared memory
`mbarrier.barrier.token` that is token
It introduces following Ops:
`mbarrier.create` creates `mbarrier.barrier`
`mbarrier.init` initializes `mbarrier.barrier`
`mbarrier.arrive` performs arrive-on `mbarrier.barrier` returns `mbarrier.barrier.token`
`mbarrier.arrive.nocomplete` performs arrive-on (non-blocking) `mbarrier.barrier` returns `mbarrier.barrier.token`
`mbarrier.test_wait` waits on `mbarrier.barrier` and `mbarrier.barrier.token`
Reviewed By: nicolasvasilache
Differential Revision: https://reviews.llvm.org/D154090
`nvgpu.device_async_copy` is lowered into `cp.async` PTX instruction. However, NVPTX backend does not support its all mode especially when zero padding is needed. Therefore, current MLIR implementation genereates inline assembly for that.
This work simplifies PTX generation for `nvgpu.device_async_copy`, and implements it by `NVVMToLLVM` Pass.
Depends on D154060
Reviewed By: nicolasvasilache, manishucsd
Differential Revision: https://reviews.llvm.org/D154345
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
This patch adds support for cache all (.ca) in conversion from nvgpu-to-nvvm for inline asm `cp.async`.
For sizes other than 16 bytes cp.async cache global is not allowed and cache all is required to generate a valid ptx.
Differential revision: https://reviews.llvm.org/D148604
Authored-by: Manish Gupta <manigupta@google.com>
The 'mma.sp.sync.aligned' family of instructions expects
the sparsity selector as a direct literal (0x0 or 0x1).
The current MLIR inline asm passed this as a value in
register, which broke the downstream assemblers
This is a small step towards supporting 2:4 sparsity on
NVidia GPUs in the sparse compiler of MLIR.
Reviewed By: ThomasRaoux, guraypp
Differential Revision: https://reviews.llvm.org/D146110
Remapping memory spaces is a function often needed in type
conversions, most often when going to LLVM or to/from SPIR-V (a future
commit), and it is possible that such remappings may become more
common in the future as dialects take advantage of the more generic
memory space infrastructure.
Currently, memory space remappings are handled by running a
special-purpose conversion pass before the main conversion that
changes the address space attributes. In this commit, this approach is
replaced by adding a notion of type attribute conversions
TypeConverter, which is then used to convert memory space attributes.
Then, we use this infrastructure throughout the *ToLLVM conversions.
This has the advantage of loosing the requirements on the inputs to
those passes from "all address spaces must be integers" to "all
memory spaces must be convertible to integer spaces", a looser
requirement that reduces the coupling between portions of MLIR.
ON top of that, this change leads to the removal of most of the calls
to getMemorySpaceAsInt(), bringing us closer to removing it.
(A rework of the SPIR-V conversions to use this new system will be in
a folowup commit.)
As a note, one long-term motivation for this change is that I would
eventually like to add an allocaMemorySpace key to MLIR data layouts
and then call getMemRefAddressSpace(allocaMemorySpace) in the
relevant *ToLLVM in order to ensure all alloca()s, whether incoming or
produces during the LLVM lowering, have the correct address space for
a given target.
I expect that the type attribute conversion system may be useful in
other contexts.
Reviewed By: ftynse
Differential Revision: https://reviews.llvm.org/D142159
This is part of an effort to migrate from llvm::Optional to
std::optional. This patch changes the way mlir-tblgen generates .inc
files, and modifies tests and documentation appropriately. It is a "no
compromises" patch, and doesn't leave the user with an unpleasant mix of
llvm::Optional and std::optional.
A non-trivial change has been made to ControlFlowInterfaces to split one
constructor into two, relating to a build failure on Windows.
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/D138934
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 change adds a new NVGPU operation that targets the PTX `mma.sp.sync`
instruction variants. A lowering to NVVM is provided using inline
assembly.
Reviewed By: ThomasRaoux, manishucsd
Differential Revision: https://reviews.llvm.org/D137202
`cp_async_zfill` is currently not present in the nvvm backend, this patch adds `cp_async_zfill` support by adding inline asm when lowering from `nvgpu` to `nvvm`.
Reviewed By: ThomasRaoux
Differential Revision: https://reviews.llvm.org/D132269
The patch introduces the required changes to update the pass declarations and definitions to use the new autogenerated files and allow dropping the old infrastructure.
Reviewed By: mehdi_amini, rriddle
Differential Review: https://reviews.llvm.org/D132838
The patch introduces the required changes to update the pass declarations and definitions to use the new autogenerated files and allow dropping the old infrastructure.
Reviewed By: mehdi_amini, rriddle
Differential Review: https://reviews.llvm.org/D132838
This patch "modernizes" the LLVM `insertvalue` and `extractvalue`
operations to use DenseI64ArrayAttr, since they only require an array of
indices and previously there was confusion about whether to use i32 or
i64 arrays, and to use assembly format.
Reviewed By: ftynse
Differential Revision: https://reviews.llvm.org/D131537
Adds optional attribute to support tensor cores on F32 datatype by lowering to `mma.sync` with TF32 operands. Since, TF32 is not a native datatype in LLVM we are adding `tf32Enabled` as an attribute to allow the IR to be aware of `MmaSyncOp` datatype. Additionally, this patch adds placeholders for nvgpu-to-nvgpu transformation targeting higher precision tf32x3.
For mma.sync on f32 input using tensor cores there are two possibilites:
(a) tf32 (1 `mma.sync` per warp-level matrix-multiply-accumulate)
(b) tf32x3 (3 `mma.sync` per warp-level matrix-multiply-accumulate)
Typically, tf32 tensor core acceleration comes at a cost of accuracy from missing precision bits. While f32 has 23 precision bits, tf32 has only 10 precision bits. tf32x3 aims to recover the precision bits by splitting each operand into two tf32 values and issue three `mma.sync` tensor core operations.
Reviewed By: ThomasRaoux
Differential Revision: https://reviews.llvm.org/D130294
Follow up from flipping dialects to both, flip accessor used to prefixed
variant ahead to flipping from _Both to _Prefixed. This just flips to
the accessors introduced in the preceding change which are just prefixed
forms of the existing accessor changed from.
Mechanical change using helper script
https://github.com/jpienaar/llvm-project/blob/main/clang-tools-extra/clang-tidy/misc/AddGetterCheck.cpp and clang-format.
This change adds a transformation and pass to the NvGPU dialect that
attempts to optimize reads/writes from a memref representing GPU shared
memory in order to avoid bank conflicts. Given a value representing a
shared memory memref, it traverses all reads/writes within the parent op
and, subject to suitable conditions, rewrites all last dimension index
values such that element locations in the final (col) dimension are
given by
`newColIdx = col % vecSize + perm[row](col/vecSize,row)`
where `perm` is a permutation function indexed by `row` and `vecSize`
is the vector access size in elements (currently assumes 128bit
vectorized accesses, but this can be made a parameter). This specific
transformation can help optimize typical distributed & vectorized accesses
common to loading matrix multiplication operands to/from shared memory.
Differential Revision: https://reviews.llvm.org/D127457
AsyncCopyOp lowering converted "size in elements" to "size in bytes"
assuming the element type size is at least one byte. This removes
that restriction, allowing for types such as i4 and b1 to be handled
correctly.
Differential Revision: https://reviews.llvm.org/D125838
This changes adds missing support for the i4 data type. Tests are added
to ensure proper lowering of an nvgpu.mma.sync operation targeting the
16x8x64xi4 and 16x8x32xi4 MMA variants in the NVVM dialect.
Differential Revision: https://reviews.llvm.org/D126092
Move async copy operations to NVGPU as they only exist on NV target and are
designed to match ptx semantic. This allows us to also add more fine grain
caching hint attribute to the op.
Add hint to bypass L1 and hook it up to NVVM op.
Differential Revision: https://reviews.llvm.org/D125244
Adds missing logic in the lowering from NvGPU to NVVM to support fp32
(in an accumulator operand) and tf32 (in multiplicand operand) types.
Fixes logic in one of the helper functions for converting the result
of a mma.sync operation with multiple 8x256bit output tiles, which is
the case for f32 outputs.
Differential Revision: https://reviews.llvm.org/D124533
