[llvm] [TableGen][GISel] Extract common function for determining MI's regclass (PR #120135)

[Matt Arsenault via llvm-commits]

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@@ -34,7 +34,7 @@ def A0  : RegisterClass<"MyTarget", [i32], 32, (add a0)>;
 // CHECK-NEXT: GIM_CheckOpcode, /*MI*/0, GIMT_Encode2(TargetOpcode::G_ANYEXT),
 // CHECK-NEXT: // MIs[0] DstI[dst]
 // CHECK-NEXT: GIM_RootCheckType, /*Op*/0, /*Type*/GILLT_s16,
-// CHECK-NEXT: GIM_RootCheckRegBankForClass, /*Op*/0, /*RC*/GIMT_Encode2(MyTarget::A0RegClassID),
+// CHECK-NEXT: GIM_RootCheckRegBankForClass, /*Op*/0, /*RC*/GIMT_Encode2(MyTarget::A0wRegClassID),
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arsenm wrote:

Not sure why this is encoded as a class and not the bank directly 

https://github.com/llvm/llvm-project/pull/120135