diff options
Diffstat (limited to 'lib/Analysis/ScalarEvolution.cpp')
-rw-r--r-- | lib/Analysis/ScalarEvolution.cpp | 26 |
1 files changed, 12 insertions, 14 deletions
diff --git a/lib/Analysis/ScalarEvolution.cpp b/lib/Analysis/ScalarEvolution.cpp index f5a762af82..b3ddfc032f 100644 --- a/lib/Analysis/ScalarEvolution.cpp +++ b/lib/Analysis/ScalarEvolution.cpp @@ -3854,14 +3854,13 @@ ScalarEvolution::ComputeBackedgeTakenCountFromExitCond(const Loop *L, else MaxBECount = getUMinFromMismatchedTypes(BTI0.Max, BTI1.Max); } else { - // Both conditions must be true for the loop to exit. + // Both conditions must be true at the same time for the loop to exit. + // For now, be conservative. assert(L->contains(FBB) && "Loop block has no successor in loop!"); - if (BTI0.Exact != getCouldNotCompute() && - BTI1.Exact != getCouldNotCompute()) - BECount = getUMaxFromMismatchedTypes(BTI0.Exact, BTI1.Exact); - if (BTI0.Max != getCouldNotCompute() && - BTI1.Max != getCouldNotCompute()) - MaxBECount = getUMaxFromMismatchedTypes(BTI0.Max, BTI1.Max); + if (BTI0.Max == BTI1.Max) + MaxBECount = BTI0.Max; + if (BTI0.Exact == BTI1.Exact) + BECount = BTI0.Exact; } return BackedgeTakenInfo(BECount, MaxBECount); @@ -3889,14 +3888,13 @@ ScalarEvolution::ComputeBackedgeTakenCountFromExitCond(const Loop *L, else MaxBECount = getUMinFromMismatchedTypes(BTI0.Max, BTI1.Max); } else { - // Both conditions must be false for the loop to exit. + // Both conditions must be false at the same time for the loop to exit. + // For now, be conservative. assert(L->contains(TBB) && "Loop block has no successor in loop!"); - if (BTI0.Exact != getCouldNotCompute() && - BTI1.Exact != getCouldNotCompute()) - BECount = getUMaxFromMismatchedTypes(BTI0.Exact, BTI1.Exact); - if (BTI0.Max != getCouldNotCompute() && - BTI1.Max != getCouldNotCompute()) - MaxBECount = getUMaxFromMismatchedTypes(BTI0.Max, BTI1.Max); + if (BTI0.Max == BTI1.Max) + MaxBECount = BTI0.Max; + if (BTI0.Exact == BTI1.Exact) + BECount = BTI0.Exact; } return BackedgeTakenInfo(BECount, MaxBECount); |