[lld] [LLD][AArch64][ARM] Delay adding long thunk mapping symbols (PR #116975)

[Fangrui Song via llvm-commits]

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@@ -69,6 +69,7 @@ class AArch64Thunk : public Thunk {
 private:
   bool mayUseShortThunk = true;
   virtual void writeLong(uint8_t *buf) = 0;
+  virtual void addLongMapSyms() {}
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MaskRay wrote:

Perhaps add some comment, something like: mapping symbols with non-zero offsets may become needed when mayUseShortThunk becomes false later.

https://github.com/llvm/llvm-project/pull/116975