[clang] [flang] [llvm] [mlir] [LLVM][NVPTX][MLIR] Support layouts in mbarrier.init and add mbarrier.check_layout (PR #217252)

[Pradeep Kumar via cfe-commits]

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schwarzschild-radius wrote:

@grypp The assembly format supports both of them together and have added tests for that. Unfortunately, due to the parser, we cannot have both optional attributes/operands prefixed with `,`

https://github.com/llvm/llvm-project/pull/217252