[mlir][AMDGPU] Plumb address space 7 through MLIR, add address_space attr. (#125594)

This commit adds support for casting memrefs into fat raw buffer
pointers to the AMDGPU dialect.

Fat raw buffer pointers - or, in LLVM terms, ptr addrspcae(7), allow
encapsulating a buffer descriptor (as produced by the make.buffer.rsrc
intrinsic or provided from some API) into a pointer that supports
ordinary pointer operations like load or store. This allows people to
take advantage of the additional semantics that buffer_load and similar
instructions provide without forcing the use of entirely separate
amdgpu.raw_buffer_* operations.

Operations on fat raw buffer pointers are translated to the
corresponding LLVM intrinsics by the backend.

This commit also goes and and defines a #amdgpu.address_space<>
attribute so that AMDGPU-specific memory spaces can be represented. Only
#amdgpu.address_space<fat_raw_buffer> will work correctly with the
memref dialect, but the other possible address spaces are included for
completeness.

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Co-authored-by: Jakub Kuderski <kubakuderski@gmail.com>
Co-authored-by: Prashant Kumar <pk5561@gmail.com>

0 files changed, 0 insertions, 0 deletions