[PATCH] D48283: [SCEV] Properly solve quadratic equations

[Eli Friedman via Phabricator via llvm-commits]

efriedma added inline comments.


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Comment at: lib/Analysis/ScalarEvolution.cpp:8270
+/// the quadratic chrec {L,+,M,+,N} equals 0 or wraps around 2^BW in the
+/// unsigned modulo 2^BW arithmetic. A signed overflow is ignored (it would
+/// correspond to wrapping around 2^(BW-1)).
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"A signed overflow is ignored" contradicts the implementation; you're treating the coefficients as signed values (by sign-extending them).


Repository:
  rL LLVM

https://reviews.llvm.org/D48283