[llvm] [WebAssembly] Add unreachable before catch destinations (PR #123915)

[Derek Schuff via llvm-commits]

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@@ -1943,8 +1951,16 @@ bool WebAssemblyCFGStackify::fixCallUnwindMismatches(MachineFunction &MF) {
   // When end_loop is before end_try_table within the same BB in unwind
   // destinations, we should split the end_loop into another BB.
   if (!WebAssembly::WasmUseLegacyEH)
-    for (auto &[UnwindDest, _] : UnwindDestToTryRanges)
-      splitEndLoopBB(UnwindDest);
+    for (auto &[UnwindDest, _] : UnwindDestToTryRanges) {
+      auto It = EHPadToTry.find(UnwindDest);
+      // If UnwindDest is the faker caller block, it will not be in EHPadToTry
----------------
dschuff wrote:

```suggestion
      // If UnwindDest is the fake caller block, it will not be in EHPadToTry
```

https://github.com/llvm/llvm-project/pull/123915