[clang] [llvm] [WebAssembly] Implement an alternative translation for -wasm-enable-sjlj (PR #84137)

[Heejin Ahn via cfe-commits]

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@@ -999,25 +1017,43 @@ bool WebAssemblyLowerEmscriptenEHSjLj::runOnModule(Module &M) {
       // Register __wasm_longjmp function, which calls __builtin_wasm_longjmp.
       FunctionType *FTy = FunctionType::get(
           IRB.getVoidTy(), {Int8PtrTy, IRB.getInt32Ty()}, false);
-      WasmLongjmpF = getEmscriptenFunction(FTy, "__wasm_longjmp", &M);
+      if (EnableWasmAltSjLj) {
+        WasmLongjmpF = getEmscriptenFunction(FTy, "__wasm_sjlj_longjmp", &M);
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aheejin wrote:

I think we discussed this in the emscripten PR.

https://github.com/llvm/llvm-project/pull/84137