[PATCH] D91325: [IndVarSimplify] Notify top most loop to drop cached exit counts

[guopeilin via Phabricator via llvm-commits]

guopeilin updated this revision to Diff 305645.
guopeilin retitled this revision from "[IndVarSimplify] Drop any stored trip count value before IndVarSimplify" to "[IndVarSimplify] Notify top most loop to drop cached exit counts".
guopeilin added a comment.

use forgetTopmostLoop() directly instead of visiting exitingBB among nested loops


CHANGES SINCE LAST ACTION
  https://reviews.llvm.org/D91325/new/

https://reviews.llvm.org/D91325

Files:
  llvm/lib/Transforms/Scalar/IndVarSimplify.cpp


Index: llvm/lib/Transforms/Scalar/IndVarSimplify.cpp
===================================================================
--- llvm/lib/Transforms/Scalar/IndVarSimplify.cpp
+++ llvm/lib/Transforms/Scalar/IndVarSimplify.cpp
@@ -1786,7 +1786,9 @@
   if (predicateLoopExits(L, Rewriter)) {
     Changed = true;
     // Given we've changed exit counts, notify SCEV
-    SE->forgetLoop(L);
+    // Some nested loops may share same folded exit basic block,
+    // thus we need to notify top most loop.
+    SE->forgetTopmostLoop(L);
   }
 
   // If we have a trip count expression, rewrite the loop's exit condition


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