[llvm] [IR] Introduce `llvm.allow.{runtime, ubsan}.check()` (PR #84850)

[Nikita Popov via llvm-commits]

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@@ -27696,6 +27696,125 @@ constant `true`. However it is always correct to replace
 it with any other `i1` value. Any pass can
 freely do it if it can benefit from non-default lowering.
 
+'``llvm.allow.ubsan.check``' Intrinsic
+^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
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nikic wrote:

Fix underline length :)

https://github.com/llvm/llvm-project/pull/84850