[PATCH] D89456: [SCEV] Introduce SCEVPtrToIntExpr (PR46786)

[Max Kazantsev via Phabricator via llvm-commits]

mkazantsev added inline comments.


================
Comment at: llvm/lib/Analysis/ScalarEvolution.cpp:8483
+    if (Op == Cast->getOperand())
+      return Cast; // must be loop invariant
+    return getPtrToIntExpr(Op, Cast->getType());
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It doesn't look like the right way to check for loop invariance. `getSCEVAtScope` can potentially simplify your expression that is still invariant. Example: you have `Op = A + B` and loop is guarded by condition `B = 0`. `getSCEVAtScope(Op)` may return `A` which is still loop invariant, but not equal to `Op`.

What you might be looking for is `isAvailableAtLoopEntry`.


Repository:
  rG LLVM Github Monorepo

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  https://reviews.llvm.org/D89456/new/

https://reviews.llvm.org/D89456