[llvm] [IR][RFC] Add @llvm.mask.beforefirst intrinsic (PR #203874)

[Luke Lau via llvm-commits]

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@@ -0,0 +1,148 @@
+; NOTE: Assertions have been autogenerated by utils/update_llc_test_checks.py UTC_ARGS: --version 6
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lukel97 wrote:

Yeah there are also RISC-V cases which will crash too due to the expansion of get_active_lane_mask, https://github.com/llvm/llvm-project/pull/226506 aims to fix these separately 

https://github.com/llvm/llvm-project/pull/203874