[llvm] [CallPromotionUtil] See through function alias when devirtualizing a virtual call on an alloca. (PR #80736)

[Mingming Liu via llvm-commits]

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@@ -77,6 +78,10 @@ void findDevirtualizableCallsForTypeCheckedLoad(
 Constant *getPointerAtOffset(Constant *I, uint64_t Offset, Module &M,
                              Constant *TopLevelGlobal = nullptr);
 
+// Given a vtable, returns the function pointer specified by Offset.
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minglotus-6 wrote:

done.  Also updated function impl to return a pair of nullptr when the not-null pointer cannot be casted to function and is not an alias to a function.

https://github.com/llvm/llvm-project/pull/80736