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

[Simon Pilgrim via llvm-commits]

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@@ -43,22 +43,48 @@ class MCInstrInfo {
   const ComplexDeprecationPredicate *ComplexDeprecationInfos;
   unsigned NumOpcodes;              // Number of entries in the desc array
 
+protected:
+  // Pointer to 2d array [NumHwModes][NumRegClassByHwModes]
+  const int16_t *RegClassByHwModeTables;
+  int16_t NumRegClassByHwModes;
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RKSimon wrote:

Could we use ArrayRef here?

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