[PATCH] D148841: [LV] Use SCEV for uniformity analysis across VF

[Florian Hahn via Phabricator via llvm-commits]

fhahn marked 2 inline comments as done.
fhahn added inline comments.


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Comment at: llvm/lib/Analysis/LoopAccessAnalysis.cpp:2570
+    // Build a new AddRec by multiplying the step by StepMultiplier and adding
+    // Offset * Step to the resulting AddRec.
+    auto *Ty = Expr->getType();
----------------
nikic wrote:
> Assert that the addrec loop is correct?
Yep that's safer, added the assert. Should help due to the invariance check in ::visit().


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Comment at: llvm/lib/Analysis/LoopAccessAnalysis.cpp:2577
+                         SE.getMulExpr(StepC, Expr->getStepRecurrence(SE)),
+                         Expr->getLoop(), Expr->getNoWrapFlags()),
+        SE.getMulExpr(OffsetC, Expr->getStepRecurrence(SE)));
----------------
nikic wrote:
> Why is it valid to preserve nowrap flags here?
It should be valid for the vector loop, as we check that the vector induction doesn't overflow/wrap; although the loop we are dealing with here is still the original scalar loop... But it's not needed so I removed it, thanks!


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https://reviews.llvm.org/D148841