Changes in directory llvm/lib/CodeGen/SelectionDAG:
TargetLowering.cpp updated: 1.80 -> 1.81 --- Log message: Fix the dag combiner bug corresponding to PR1014: http://llvm.org/PR1014 . --- Diffs of the changes: (+8 -8) TargetLowering.cpp | 16 ++++++++-------- 1 files changed, 8 insertions(+), 8 deletions(-) Index: llvm/lib/CodeGen/SelectionDAG/TargetLowering.cpp diff -u llvm/lib/CodeGen/SelectionDAG/TargetLowering.cpp:1.80 llvm/lib/CodeGen/SelectionDAG/TargetLowering.cpp:1.81 --- llvm/lib/CodeGen/SelectionDAG/TargetLowering.cpp:1.80 Thu Nov 9 12:56:43 2006 +++ llvm/lib/CodeGen/SelectionDAG/TargetLowering.cpp Mon Nov 27 15:50:02 2006 @@ -363,20 +363,20 @@ return TLO.CombineTo(Op, Op.getOperand(0)); if ((DemandedMask & KnownZero2) == DemandedMask) return TLO.CombineTo(Op, Op.getOperand(1)); + + // If all of the unknown bits are known to be zero on one side or the other + // (but not both) turn this into an *inclusive* or. + // e.g. (A & C1)^(B & C2) -> (A & C1)|(B & C2) iff C1&C2 == 0 + if ((DemandedMask & ~KnownZero & ~KnownZero2) == 0) + return TLO.CombineTo(Op, TLO.DAG.getNode(ISD::OR, Op.getValueType(), + Op.getOperand(0), + Op.getOperand(1))); // Output known-0 bits are known if clear or set in both the LHS & RHS. KnownZeroOut = (KnownZero & KnownZero2) | (KnownOne & KnownOne2); // Output known-1 are known to be set if set in only one of the LHS, RHS. KnownOneOut = (KnownZero & KnownOne2) | (KnownOne & KnownZero2); - // If all of the unknown bits are known to be zero on one side or the other - // (but not both) turn this into an *inclusive* or. - // e.g. (A & C1)^(B & C2) -> (A & C1)|(B & C2) iff C1&C2 == 0 - if (uint64_t UnknownBits = DemandedMask & ~(KnownZeroOut|KnownOneOut)) - if ((UnknownBits & (KnownZero|KnownZero2)) == UnknownBits) - return TLO.CombineTo(Op, TLO.DAG.getNode(ISD::OR, Op.getValueType(), - Op.getOperand(0), - Op.getOperand(1))); // If all of the demanded bits on one side are known, and all of the set // bits on that side are also known to be set on the other side, turn this // into an AND, as we know the bits will be cleared. _______________________________________________ llvm-commits mailing list llvm-commits@cs.uiuc.edu http://lists.cs.uiuc.edu/mailman/listinfo/llvm-commits
