6 Commits

Author SHA1 Message Date
Kazu Hirata
1a36588ec6 [mlir] Use std::nullopt instead of None (NFC)
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
2022-12-03 18:50:27 -08:00
Krzysztof Drewniak
d6abdf46bc [mlir][AMDGPU] Remove buffer ops that are statically out of bounds
When the bounds check attribute is true, the raw buffer load, store,
and atomic operations have well-defined behavior (returning 0 for
loads and ignoring stores) when the buffer access exceeds the bounds
of the memory being accessed.

Because of how LLVM currently implements these buffer operations (as
opaque intrinsics), the backend cannot optimize out this known
behavior and eliminate the memory operations. Therefore, use MLIR's
canonicalization system to eliminate these operations.

Reviewed By: nirvedhmeshram

Differential Revision: https://reviews.llvm.org/D138146
2022-11-21 16:47:21 +00:00
Rob Suderman
7e52e0fc72 [mlir][amdgpu] Fix signed/unsigned comparison for abid/cbsz comparison
Unsigned/signed comparison failure due to implicit signed value.

Reviewed By: stella.stamenova

Differential Revision: https://reviews.llvm.org/D133061
2022-08-31 15:29:31 -07:00
Krzysztof Drewniak
c55b41d519 [mlir][AMDGPU] Define amdgpu.mfma operator
The amdgpu.mfma operator is a wrapper around the Matrix Fused Multiply
Add (MFMA) instructions on some AMD GPUs (the CDNA-based MI-* cards).

This interface allows for selecting the operation to be performed by
specifying the dimensions of the multiplication to be performed and
any additional attributes (such as whether to use reduced-precision
floating-point math) that are needed to select the relevant mfma
instruction and set its parameters.

Reviewed By: ThomasRaoux, nirvedhmeshram

Differential Revision: https://reviews.llvm.org/D132956
2022-08-31 21:06:12 +00:00
Jacques Pienaar
8df54a6a03 [mlir] Update accessors to prefixed form (NFC)
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.
2022-06-18 17:53:22 -07:00
Krzysztof Drewniak
f1f05a91ca [MLIR][AMDGPU] Add AMDGPU dialect, wrappers around raw buffer intrinsics
By analogy with the NVGPU dialect, introduce an AMDGPU dialect for
AMD-specific intrinsic wrappers.

The dialect initially includes wrappers around the raw buffer intrinsics.

On AMD GPUs, a memref can be converted to a "buffer descriptor" that
allows more precise control of memory access, such as by allowing for
out of bounds loads/stores to be replaced by 0/ignored without adding
additional conditional logic, which is important for performance.

The repository currently contains a limited conversion from
transfer_read/transfer_write to Mubuf intrinsics, which are an older,
deprecated intrinsic for the same functionality.

The new amdgpu.raw_buffer_* ops allow these operations to be used
explicitly and for including metadata such as whether the target
chipset is an RDNA chip or not (which impacts the interpretation of
some bits in the buffer descriptor), while still maintaining an
MLIR-like interface.

(This change also exposes the floating-point atomic add intrinsic.)

Reviewed By: ThomasRaoux

Differential Revision: https://reviews.llvm.org/D122765
2022-05-10 14:59:58 +00:00