[PATCH] D33316: [SCEV] Do not fold expressions with SCEVUnknown Phis into AddRecExpr's

[Max Kazantsev via Phabricator via llvm-commits]

mkazantsev added inline comments.


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Comment at: lib/Analysis/ScalarEvolution.cpp:2210
+      auto *SU = dyn_cast<SCEVUnknown>(S);
+      if (auto *Phi = dyn_cast<PHINode>(SU->getValue()))
+        if (auto *PL = LI.getLoopFor(Phi->getParent()))
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sanjoy wrote:
> I'm not sure why this can't happen with non-PHIs.  IMO the condition should be "the expression the SCEVUnknown corresponds to must dominate L->getHeader()".
Good point, the same situation could happen if we applied non-SCEVable operation with our Phi.


https://reviews.llvm.org/D33316