[llvm] [RISCV] Refactor X60 scheduling model helper classes. NFC. (PR #151572)

[Mikhail R. Gadelha via llvm-commits]

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@@ -13,78 +13,108 @@
 //
 //===----------------------------------------------------------------------===//
 
-class SMX60IsWorstCaseMX<string mx, list<string> MxList> {
-  string LLMUL = LargestLMUL<MxList>.r;
-  bit c = !eq(mx, LLMUL);
-}
+//===----------------------------------------------------------------------===//
+// Helpers
+
+// Maps LMUL string to corresponding value from the Values array
+// LMUL values map to array indices as follows:
+//   MF8 -> Values[0], MF4 -> Values[1], MF2 -> Values[2], M1 -> Values[3],
+//   M2 -> Values[4], M4 -> Values[5], M8 -> Values[6]
+// Shorter lists are allowed, e.g., widening instructions don't work on M8
+class GetLMULValue<list<int> Values, string LMUL> {
+  int Index = !cond(
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mikhailramalho wrote:

done.

https://github.com/llvm/llvm-project/pull/151572