[llvm] [PowerPC] Function descriptor symbol can be omitted for external symbol. (PR #97526)

[Chen Zheng via llvm-commits]

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@@ -2325,8 +2325,15 @@ bool AsmPrinter::doFinalization(Module &M) {
     // Emit linkage for the function entry point.
     emitLinkage(&F, FnEntryPointSym);
 
-    // Emit linkage for the function descriptor.
-    emitLinkage(&F, Name);
+    // If address is taken from an extern function, we need to emit linkage for
+    // its function descriptor symbol.
+    if (F.hasAddressTaken(/*PutOffender=*/nullptr,
+                          /*IgnoreCallbackUses=*/false,
+                          /*IgnoreAssumeLikeCalls=*/true,
+                          /*IgnoreLLVMUsed=*/true,
+                          /*IgnoreARCAttachedCall=*/false,
+                          /*IgnoreCastedDirectCall=*/true))
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chenzheng1030 wrote:

Since you change the default values for parameters `IgnoreLLVMUsed` and `IgnoreCastedDirectCall`, would you please share the C or C++ cases where function declarations are used like these two types? Thanks.

https://github.com/llvm/llvm-project/pull/97526