[llvm] change contents of ScalarEvolution from private to protected (PR #83052)

[Nikita Popov via llvm-commits]

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@@ -8923,10 +8949,104 @@ ScalarEvolution::ExitLimit ScalarEvolution::computeExitLimitFromCondCached(
 ScalarEvolution::ExitLimit ScalarEvolution::computeExitLimitFromCondImpl(
     ExitLimitCacheTy &Cache, const Loop *L, Value *ExitCond, bool ExitIfTrue,
     bool ControlsOnlyExit, bool AllowPredicates) {
-  // Handle BinOp conditions (And, Or).
-  if (auto LimitFromBinOp = computeExitLimitFromCondFromBinOp(
-          Cache, L, ExitCond, ExitIfTrue, ControlsOnlyExit, AllowPredicates))
-    return *LimitFromBinOp;
+  if (!AssumeLoopExists) {
+    // Handle BinOp conditions (And, Or).
+    if (auto LimitFromBinOp = computeExitLimitFromCondFromBinOp(
+            Cache, L, ExitCond, ExitIfTrue, ControlsOnlyExit, AllowPredicates))
+      return *LimitFromBinOp;
+  } else {
+    // Check if the controlling expression for this loop is an And or Or.
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nikic wrote:

Shouldn't this code be integrated in computeExitLimitFromCondFromBinOp?

https://github.com/llvm/llvm-project/pull/83052