Create a MaxMatrixDimension language option.

[farzonl]

The goal should likely be to replace the constexpr MaxElementsPerDimension with this language option.

llvm-project/clang/include/clang/AST/TypeBase.h

Lines 4371 to 4379 in 129c683

	class ConstantMatrixType final : public MatrixType {
	protected:
	friend class ASTContext;
	/// Number of rows and columns.
	unsigned NumRows;
	unsigned NumColumns;
	static constexpr unsigned MaxElementsPerDimension = (1 << 20) - 1;

But that would require updating all of these static constexpr functions with something that takes a SemaPtr

llvm-project/clang/include/clang/AST/TypeBase.h

Lines 4399 to 4407 in 129c683

	/// Returns true if \p NumElements is a valid matrix dimension.
	static constexpr bool isDimensionValid(size_t NumElements) {
	return NumElements > 0 && NumElements <= MaxElementsPerDimension;
	}
	/// Returns the maximum number of elements per dimension.
	static constexpr unsigned getMaxElementsPerDimension() {
	return MaxElementsPerDimension;
	}

For now we will make this an HLSL only language opt and create an issue to make it more generic:

VALUE_LANGOPT(HLSLMaxMatrixDimension, 32, 4, NotCompatible, "maximum allowed matrix dimension")

Originally posted by @farzonl in #159446 (comment)

[llvmbot]

@llvm/issue-subscribers-clang-frontend

Author: Farzon Lotfi (farzonl)

The goal should likely be to replace the constexpr `MaxElementsPerDimension` with this language option. https://github.com/llvm/llvm-project/blob/129c6836b772988b77b60683f8b1e6d65ddc1ce4/clang/include/clang/AST/TypeBase.h#L4371-L4379

But that would require updating all of these static constexpr functions with something that takes a SemaPtr

llvm-project/clang/include/clang/AST/TypeBase.h

Lines 4399 to 4407 in 129c683

	/// Returns true if \p NumElements is a valid matrix dimension.
	static constexpr bool isDimensionValid(size_t NumElements) {
	return NumElements > 0 && NumElements <= MaxElementsPerDimension;
	}
	/// Returns the maximum number of elements per dimension.
	static constexpr unsigned getMaxElementsPerDimension() {
	return MaxElementsPerDimension;
	}

For now we will make this an HLSL only language opt and create an issue to make it more generic:

VALUE_LANGOPT(HLSLMaxMatrixDimension, 32, 4, NotCompatible, "maximum allowed matrix dimension")

Originally posted by @farzonl in #159446 (comment)