[llvm] CodeGen: Add RegisterClass by HwMode (PR #158269)

[Craig Topper via llvm-commits]

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@@ -1316,6 +1394,14 @@ void InstrInfoEmitter::emitEnums(
   }
   OS << "    INSTRUCTION_LIST_END = " << NumberedInstructions.size() << '\n';
   OS << "  };\n";
+
+  if (!Target.getAllRegClassByHwMode().empty()) {
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topperc wrote:

Should we put `Target.getAllRegClassByHwMode()` in a variable instead of calling it twice?

https://github.com/llvm/llvm-project/pull/158269