[clang] Basic, Sema: introduce `__attribute__((__personality__(...)))` (PR #185225)

[Saleem Abdulrasool via cfe-commits]

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@@ -1655,6 +1655,15 @@ void CodeGenFunction::GenerateCode(GlobalDecl GD, llvm::Function *Fn,
 
   PGO->verifyCounterMap();
 
+  if (CurCodeDecl->hasAttr<PersonalityAttr>()) {
+    StringRef Identifier =
+        CurCodeDecl->getAttr<PersonalityAttr>()->getRoutine()->getName();
+    llvm::FunctionCallee PersonalityRoutine =
+        CGM.CreateRuntimeFunction(llvm::FunctionType::get(CGM.Int32Ty, true),
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compnerd wrote:

Ah, that is fair. I don't think that it matters on most targets. The only target that comes to mind where this matters is WASM, where I don't know if this would be as useful. In fact, I'm not sure what happens there right now - we treat all of the personality routines as the type that I'm using here - `int (*)(...);`.

The information is only used to generate the `eh_frame` or SEH entry, which needs a nominal reference to the personality routine rather than forming an actual call. The calls are runtime only done through the indirect function call.

https://github.com/llvm/llvm-project/pull/185225