[llvm] [TableGen] Add a DenseSet to track WriteRes that are referenced by some ReadAdvance. NFC (PR #124160)

[Min-Yih Hsu via llvm-commits]

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@@ -2173,12 +2175,7 @@ bool CodeGenProcModel::isUnsupported(const CodeGenInstruction &Inst) const {
 }
 
 bool CodeGenProcModel::hasReadOfWrite(const Record *WriteDef) const {
-  for (auto &RADef : ReadAdvanceDefs) {
-    ConstRecVec ValidWrites = RADef->getValueAsListOfDefs("ValidWrites");
-    if (is_contained(ValidWrites, WriteDef))
-      return true;
-  }
-  return false;
+  return ReadOfWriteSet.count(WriteDef) != 0;
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mshockwave wrote:

maybe just `return ReadOfWriteSet.count(WriteDef);`?

https://github.com/llvm/llvm-project/pull/124160