[llvm] [AArch64, ELF] Allow implicit $d/$x at section beginning (PR #99718)

[Fangrui Song via llvm-commits]

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@@ -269,15 +281,15 @@ class AArch64ELFStreamer : public MCELFStreamer {
     LastEMS = EMS_A64;
   }
 
-  void emitMappingSymbol(StringRef Name) {
+  MCSymbol *emitMappingSymbol(StringRef Name) {
     auto *Symbol = cast<MCSymbolELF>(getContext().createLocalSymbol(Name));
     emitLabel(Symbol);
-    Symbol->setType(ELF::STT_NOTYPE);
-    Symbol->setBinding(ELF::STB_LOCAL);
+    return Symbol;
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MaskRay wrote:

I've made a NFC change to use `llvm-readelf -s` in `mapping-within-section.s` to check binding/type and removed the code separately.

https://github.com/llvm/llvm-project/pull/99718