[lld] [LLD][COFF] Add support for ARM64X same-address thunks (PR #151255)

[Jacek Caban via llvm-commits]

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@@ -2310,6 +2313,18 @@ void Writer::createECChunks() {
       ctx.symtab.findUnderscore("__arm64x_redirection_metadata");
   replaceSymbol<DefinedSynthetic>(entryPointsSym, entryPointsSym->getName(),
                                   entryPoints);
+
+  for (auto thunk : ctx.symtab.sameAddressThunks) {
+    wowthkSec->insertChunkAtStart(thunk);
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cjacek wrote:

`wowthkSec` is also used by thunks provided by object files, so they would be inserted after those. I did it this way because it more closely matches MSVC's behavior (in terms of placement, not necessarily order). I moved the insertion into `createSection`, where `wowthkSec` is still empty. We also add some other chunks there.

https://github.com/llvm/llvm-project/pull/151255