[PATCH] D117307: [LoopVectorize] Only check for ordered reductions if the op chain was found

[David Sherwood via Phabricator via llvm-commits]

david-arm added inline comments.


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Comment at: llvm/lib/Analysis/IVDescriptors.cpp:1041
 SmallVector<Instruction *, 4>
-RecurrenceDescriptor::getReductionOpChain(PHINode *Phi, Loop *L) const {
+RecurrenceDescriptor::getReductionOpChain(PHINode *Phi, Loop *L,
+                                          Instruction *LoopExitInstr,
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nit: Thanks for addressing my previous comment - it looks a lot neater now and easier to review. :) Given that `RecurrenceDescriptor` now has both `getReductionOpChain` and `getReductionChain` functions, is it worth renaming `getReductionOpChain` to something like `findReductionOpChain`?


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Comment at: llvm/lib/Analysis/IVDescriptors.cpp:1087
   // from the phi and one from a LCSSA value, no matter the type.
-  if (!isCorrectOpcode(LoopExitInstr) || !LoopExitInstr->hasNUses(2))
     return {};
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Sorry I missed this before - perhaps this change shouldn't be part of this patch because it looks like it may be adding new cases that aren't being tested for correctness?


CHANGES SINCE LAST ACTION
  https://reviews.llvm.org/D117307/new/

https://reviews.llvm.org/D117307