[lld] [LLD][COFF] Add support for ARM64EC auxiliary IAT (PR #108304)

[Jacek Caban via llvm-commits]

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@@ -362,6 +362,10 @@ class ImportFile : public InputFile {
   const coff_import_header *hdr;
   Chunk *location = nullptr;
 
+  // Auxiliary IAT symbol and chunk on ARM64EC.
+  DefinedImportData *impECSym = nullptr;
+  Chunk *auxLocation = nullptr;
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cjacek wrote:

Yes, it's filled with `setLocation` in `IdataContents::create`, like other `DefinedImportData` symbols.

https://github.com/llvm/llvm-project/pull/108304