[llvm] [X86] Support EGPR (R16-R31) for APX (PR #67702)

[Shengchen Kan via llvm-commits]

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@@ -150,6 +150,11 @@ class X86InstrInfo final : public X86GenInstrInfo {
 public:
   explicit X86InstrInfo(X86Subtarget &STI);
 
+  const TargetRegisterClass *
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KanRobert wrote:

It's an overloaded function, and was already doxygened in TargetInstrInfo.h.  Do you want me to copy the comments?

https://github.com/llvm/llvm-project/pull/67702