[llvm] [BoundsChecking] Add guard= pass parameter (PR #122575)

[Vitaly Buka via llvm-commits]

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@@ -29,6 +29,7 @@ class BoundsCheckingPass : public PassInfoMixin<BoundsCheckingPass> {
     };
     std::optional<Runtime> Rt; // Trap if empty.
     bool Merge = false;
+    std::optional<int8_t> GuardKind; // `allow_ubsan_check` argument.
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vitalybuka wrote:

because this is the type acceptable by allow_ubsan_check

https://github.com/llvm/llvm-project/pull/122575