[clang] [mlir] [CIR] Implement "uniform_work_group_size" func attribute. (PR #214708)

[Akimasa Watanuki via cfe-commits]

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Men-cotton wrote:

Is `LLVM::InvokeOp` support intentionally out of scope for this PR?

`cir.try_call` is lowered through `rewriteCallOrInvoke`, which copies the call attributes onto the resulting `LLVM::InvokeOp`. This patch adds `uniform_work_group_size` to `LLVM::CallOp` and its LLVM IR import/export paths, but I don't see corresponding handling for `LLVM::InvokeOp`.

https://github.com/llvm/llvm-project/pull/214708