From c721223f7379229f6d813051bb94c999dd693073 Mon Sep 17 00:00:00 2001 From: Nick Lewycky Date: Sat, 18 Aug 2007 23:18:03 +0000 Subject: [PATCH] Never insert duplicate edges. git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@41169 91177308-0d34-0410-b5e6-96231b3b80d8 --- lib/Transforms/Scalar/PredicateSimplifier.cpp | 28 +++++++++++-------- 1 file changed, 16 insertions(+), 12 deletions(-) diff --git a/lib/Transforms/Scalar/PredicateSimplifier.cpp b/lib/Transforms/Scalar/PredicateSimplifier.cpp index 972e875d4b0..e27bac50d7a 100644 --- a/lib/Transforms/Scalar/PredicateSimplifier.cpp +++ b/lib/Transforms/Scalar/PredicateSimplifier.cpp @@ -711,23 +711,27 @@ namespace { ++J; } - if (J != E && J->To == n && J->Subtree->dominates(Subtree)) { + if (J != E && J->To == n) { + assert(J->Subtree->dominates(Subtree)); + edge.LV = static_cast(J->LV & R); assert(validPredicate(edge.LV) && "Invalid union of lattice values."); - if (edge.LV != J->LV) { - // We have to tighten any edge beneath our update. - for (iterator K = I; K->To == n; --K) { - if (K->Subtree->DominatedBy(Subtree)) { - LatticeVal LV = static_cast(K->LV & edge.LV); - assert(validPredicate(LV) && "Invalid union of lattice values"); - K->LV = LV; - } - if (K == B) break; + if (edge.LV == J->LV) + return; // This update adds nothing new. + } + + if (I != B) { + // We also have to tighten any edge beneath our update. + for (iterator K = I - 1; K->To == n; --K) { + if (K->Subtree->DominatedBy(Subtree)) { + LatticeVal LV = static_cast(K->LV & edge.LV); + assert(validPredicate(LV) && "Invalid union of lattice values"); + K->LV = LV; } - + if (K == B) break; } - } + } // Insert new edge at Subtree if it isn't already there. if (I == E || I->To != n || Subtree != I->Subtree)