[llvm] [llvm][GlobalOpt] Optimize statically resolvable IFuncs (PR #80606)

[Nikita Popov via llvm-commits]

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@@ -2404,6 +2405,42 @@ static bool OptimizeEmptyGlobalCXXDtors(Function *CXAAtExitFn) {
   return Changed;
 }
 
+static Function *hasSideeffectFreeStaticResolution(GlobalIFunc &IF) {
+  Function *Resolver = IF.getResolverFunction();
+  if (!Resolver)
+    return nullptr;
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nikic wrote:

You need to guard against interposable linkage here, e.g. `weak`. Unless this is forbidden for ifuncs?

https://github.com/llvm/llvm-project/pull/80606