[mlir][spirv] Fix coop matrix load

[kuhar]

• Fix order of operands/attributes
• Allow for stride to be any integer type
• Use ODS for parsing/printing
• Update examples and tests
• Fix a typo in SPIR-V tblgen code

[qedawkins]

Looking at the spec the stride seems to be optional: https://htmlpreview.github.io/?https://github.com/KhronosGroup/SPIRV-Registry/blob/master/extensions/KHR/SPV_KHR_cooperative_matrix.html
unless I am misinterpreting it. Should we try to match the optionality in the spec here?

[kuhar]

Looking at the spec the stride seems to be optional: https://htmlpreview.github.io/?https://github.com/KhronosGroup/SPIRV-Registry/blob/master/extensions/KHR/SPV_KHR_cooperative_matrix.html unless I am misinterpreting it. Should we try to match the optionality in the spec here?

Matching this two-level optionality (operand and attribute) is not possible without changes on the tablegen side (

llvm-project/mlir/tools/mlir-tblgen/SPIRVUtilsGen.cpp

Lines 931 to 935 in 8669a9f

	if (i != e - 1) {
	PrintFatalError(loc, "SPIR-V ops can have Variadic<..> or "
	"std::optional<...> arguments only if "
	"it's the last argument");
	}

). Would be nice to have so that we can deserialize SPIR-V blobs that rely on this, but I think having it as non-optional simplifies things.

[qedawkins]

I see, leaving it as TODO makes sense then. Thanks for the explanation!