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

[Ulrich Weigand via llvm-commits]

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@@ -30,10 +31,15 @@ class MCSymbolGOFF : public MCSymbol {
   GOFF::ESDLinkageType Linkage = GOFF::ESDLinkageType::ESD_LT_XPLink;
 
   enum SymbolFlags : uint16_t {
-    SF_Hidden = 0x01, // Symbol is hidden, aka not exported.
-    SF_Weak = 0x02,   // Symbol is weak.
+    SF_Hidden = 0x01,    // Symbol is hidden, aka not exported.
+    SF_Weak = 0x02,      // Symbol is weak.
+    SF_Indirect = 0x200, // Symbol referenced indirectly.
   };
 
+  mutable StringRef ExternalName; // Alternate external name.
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uweigand wrote:

Also better to have as one of the first elements to minimize alignment padding.

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