[lld] [LLD][COFF] Add support for including native ARM64 objects in ARM64EC images (PR #137653)

[Martin Storsjö via llvm-commits]

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@@ -657,7 +656,7 @@ void LinkerDriver::setMachine(MachineTypes machine) {
 
   ctx.config.machine = machine;
 
-  if (machine != ARM64X) {
+  if (!isArm64EC(machine)) {
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mstorsjo wrote:

So this change makes us create two symbol tables for all arm64ec linking, even if the very fast majority of them ever only will use one of them?

That feels odd, but I guess it's good for consistency - otherwise we'd probably have lots of bugs for the very rare cases when we do need both symbol tables for arm64ec. And I guess this is the change which forces the extra `(EC symbol)` to be printed in many tests.

https://github.com/llvm/llvm-project/pull/137653