[llvm] [X86][MC] Support encoding of EGPR for APX (PR #71909)

[Phoebe Wang via llvm-commits]

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@@ -548,7 +609,7 @@ void X86MCCodeEmitter::emitMemModRMByte(
         // movq loads is a subset of reloc_riprel_4byte_relax_rex. It is a
         // special case because COFF and Mach-O don't support ELF's more
         // flexible R_X86_64_REX_GOTPCRELX relaxation.
-        assert(Kind == REX);
+        assert(Kind == REX || Kind == REX2);
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phoebewang wrote:

Should add TODO here too?

https://github.com/llvm/llvm-project/pull/71909