[llvm] [VP][RISCV] Add a vp.load.ff intrinsic for fault only first load. (PR #128593)

[Luke Lau via llvm-commits]

lukel97 wrote:

> Would it be possible to also add a generic lowering like for the other VP intrinsics? I think in general we try to complement intrinsics with a default lowering, to avoid crashes in the backends, like https://llvm.godbolt.org/z/89sf8WbYs

I'm not sure if it is possible to add a generic lowering, at least not easily. This relies on the hardware having an instruction to probe memory that would otherwise trap when normally accessed.

https://github.com/llvm/llvm-project/pull/128593