[llvm] [LoopUnroll] Rotate loop before unrolling inside of UnrollRuntimeLoopRemainder (PR #148243)

[Marek Sedláček via llvm-commits]

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@@ -587,21 +536,116 @@ llvm::UnrollLoop(Loop *L, UnrollLoopOptions ULO, LoopInfo *LI,
       UnrollRuntimeEpilog.getNumOccurrences() ? UnrollRuntimeEpilog
                                               : isEpilogProfitable(L);
 
-  if (ULO.Runtime &&
-      !UnrollRuntimeLoopRemainder(L, ULO.Count, ULO.AllowExpensiveTripCount,
-                                  EpilogProfitability, ULO.UnrollRemainder,
-                                  ULO.ForgetAllSCEV, LI, SE, DT, AC, TTI,
-                                  PreserveLCSSA, ULO.SCEVExpansionBudget,
-                                  ULO.RuntimeUnrollMultiExit, RemainderLoop)) {
+  bool LoopRotated = false;
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mark-sed wrote:

This flag is also used on line 591 to determine if `LoopUnrollResult::Modified` or `LoopUnrollResult::Unmodified` should be returned.

https://github.com/llvm/llvm-project/pull/148243