[llvm] [SystemZ] Handle indirect symbols (PR #180815)

[Ulrich Weigand via llvm-commits]

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@@ -358,10 +359,11 @@ void GOFFWriter::defineLabel(const MCSymbolGOFF &Symbol) {
 }
 
 void GOFFWriter::defineExtern(const MCSymbolGOFF &Symbol) {
-  GOFFSymbol ER(Symbol.getName(), Symbol.getIndex(), RootSD->getOrdinal(),
-                GOFF::ERAttr{Symbol.getCodeData(), Symbol.getBindingStrength(),
-                             Symbol.getLinkage(), GOFF::ESD_AMODE_64,
-                             Symbol.getBindingScope()});
+  GOFFSymbol ER(Symbol.getNameInObjectFile(), Symbol.getIndex(),
+                RootSD->getOrdinal(),
+                GOFF::ERAttr{Symbol.isIndirect(), Symbol.getCodeData(),
+                             Symbol.getBindingStrength(), Symbol.getLinkage(),
+                             GOFF::ESD_AMODE_64, Symbol.getBindingScope()});
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uweigand wrote:

I guess we should also use the `ExternalName` for ED section labels?   My understanding is that you can use HLASM ALIAS statements for those too.  In fact, you can use HLASM ALIAS also for CSECT and the like, so should *sections* also carry an `ExternalName`?

https://github.com/llvm/llvm-project/pull/180815