Refactor alignment attributes to use `llvm::MaybeAlign` and the `IntValidAlignment` constraint

[amd-eochoalo]

The IntValidAlignment constraint is currently being used in the vector dialect to verify that the alignment is a positive integer power of two. The memref and SPIR-V dialects also contain operations which denote the alignment of memory operations, however they do not yet use the IntValidAlignment constraint.

After modifying the memory operations in the memref and SPIR-V dialects to use the IntValidAlignment constraint, one can also create constructors for these operations which take an instance of llvm::MaybeAlign as an optional parameter similar to how constructors in the vector dialect are defined here:

llvm-project/mlir/include/mlir/Dialect/Vector/IR/VectorOps.td

Lines 1726 to 1734 in a3eb311

	OpBuilder<(ins "VectorType":$resultType,
	"Value":$base,
	"ValueRange":$indices,
	CArg<"bool", "false">:$nontemporal,
	CArg<"llvm::MaybeAlign", "llvm::MaybeAlign()">:$alignment), [{
	return build($_builder, $_state, resultType, base, indices, nontemporal,
	alignment.has_value() ? $_builder.getI64IntegerAttr(alignment->value()) :
	nullptr);
	}]>,

Finally, one improvement that can be made to all three dialects is to create an interface which returns an llvm::MaybeAlign as opposed to an std::optional<uint64_t>. It could be named getMaybeAlign.

[llvmbot]

Hi!

This issue may be a good introductory issue for people new to working on LLVM. If you would like to work on this issue, your first steps are:

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3. Fix the issue locally.
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If you have any further questions about this issue, don't hesitate to ask via a comment in the thread below.

[llvmbot]

@llvm/issue-subscribers-good-first-issue

Author: Erick Ochoa Lopez (amd-eochoalo)

[The `IntValidAlignment` constraint](https://github.com//pull/155259) is currently being used in the vector dialect to verify that the alignment is a positive integer power of two. The memref and SPIR-V dialects also contain operations which denote the alignment of memory operations, however they do not yet use the `IntValidAlignment` constraint.

After modifying the memory operations in the memref and SPIR-V dialects to use the IntValidAlignment constraint, one can also create constructors for these operations which take an instance of llvm::MaybeAlign as an optional parameter similar to how constructors in the vector dialect are defined here:

llvm-project/mlir/include/mlir/Dialect/Vector/IR/VectorOps.td

Lines 1726 to 1734 in a3eb311

	OpBuilder<(ins "VectorType":$resultType,
	"Value":$base,
	"ValueRange":$indices,
	CArg<"bool", "false">:$nontemporal,
	CArg<"llvm::MaybeAlign", "llvm::MaybeAlign()">:$alignment), [{
	return build($_builder, $_state, resultType, base, indices, nontemporal,
	alignment.has_value() ? $_builder.getI64IntegerAttr(alignment->value()) :
	nullptr);
	}]>,

Finally, one improvement that can be made to all three dialects is to create an interface which returns an llvm::MaybeAlign as opposed to an std::optional<uint64_t>. It could be named getMaybeAlign.

[llvmbot]

@llvm/issue-subscribers-mlir

Author: Erick Ochoa Lopez (amd-eochoalo)

[The `IntValidAlignment` constraint](https://github.com//pull/155259) is currently being used in the vector dialect to verify that the alignment is a positive integer power of two. The memref and SPIR-V dialects also contain operations which denote the alignment of memory operations, however they do not yet use the `IntValidAlignment` constraint.

After modifying the memory operations in the memref and SPIR-V dialects to use the IntValidAlignment constraint, one can also create constructors for these operations which take an instance of llvm::MaybeAlign as an optional parameter similar to how constructors in the vector dialect are defined here:

llvm-project/mlir/include/mlir/Dialect/Vector/IR/VectorOps.td

Lines 1726 to 1734 in a3eb311

	OpBuilder<(ins "VectorType":$resultType,
	"Value":$base,
	"ValueRange":$indices,
	CArg<"bool", "false">:$nontemporal,
	CArg<"llvm::MaybeAlign", "llvm::MaybeAlign()">:$alignment), [{
	return build($_builder, $_state, resultType, base, indices, nontemporal,
	alignment.has_value() ? $_builder.getI64IntegerAttr(alignment->value()) :
	nullptr);
	}]>,

Finally, one improvement that can be made to all three dialects is to create an interface which returns an llvm::MaybeAlign as opposed to an std::optional<uint64_t>. It could be named getMaybeAlign.

[nimit25]

Can I please volunteer for this issue? Thank you!

[amd-eochoalo]

@nimit25 , sure! Please feel free to ask questions. It may be better to split this ticket into two PRs. One where the alignment attributes are constraint by IntValidConstraint and the other one with the interface and constructors.

[jiang1997]

@nimit25, are you still working on this task? It seems there hasn't been any progress for two weeks.

[nimit25]

Haven't had a chance to start on it. Looks you beat me to the PR. You can go ahead with the implementation :)