[llvm] [LLVM][Tablegen] Add Default arguments support for Intrinsics in TableGen (PR #198557)

[Min-Yih Hsu via llvm-commits]

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mshockwave wrote:

I'm pretty sure the number of arguments is relatively small, so I think we could use SmallVector here. In fact, I think `PerIntrinsic` below could also be SmallVector.

https://github.com/llvm/llvm-project/pull/198557