[llvm] [NFC][TableGen] Code cleanup in CodeGenRegister (PR #137994)

[Jason Eckhardt via llvm-commits]

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@@ -2135,28 +2115,33 @@ void CodeGenRegBank::computeRegUnitSets() {
   if (RegUnitSets.empty())
     PrintFatalError("RegUnitSets cannot be empty!");
 
-  LLVM_DEBUG(dbgs() << "\nBefore pruning:\n"; for (unsigned USIdx = 0,
-                                                   USEnd = RegUnitSets.size();
-                                                   USIdx < USEnd; ++USIdx) {
-    dbgs() << "UnitSet " << USIdx << " " << RegUnitSets[USIdx].Name << ":";
-    for (auto &U : RegUnitSets[USIdx].Units)
-      printRegUnitName(U);
-    dbgs() << "\n";
+  LLVM_DEBUG({
+    dbgs() << "\nBefore pruning:\n";
+    for (auto [USIdx, US] : enumerate(RegUnitSets)) {
+      dbgs() << "UnitSet " << USIdx << " " << US.Name << ":";
+      for (auto &U : US.Units)
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nvjle wrote:

Use `formatv` or `llvm::interleaved` to eliminate loop? 
But if this stays as is, don't "always auto".

https://github.com/llvm/llvm-project/pull/137994