diff options
Diffstat (limited to 'llvm/lib/CodeGen/SelectionDAG/SelectionDAG.cpp')
| -rw-r--r-- | llvm/lib/CodeGen/SelectionDAG/SelectionDAG.cpp | 5 |
1 files changed, 4 insertions, 1 deletions
diff --git a/llvm/lib/CodeGen/SelectionDAG/SelectionDAG.cpp b/llvm/lib/CodeGen/SelectionDAG/SelectionDAG.cpp index 33b9b333765..efcb6158ed3 100644 --- a/llvm/lib/CodeGen/SelectionDAG/SelectionDAG.cpp +++ b/llvm/lib/CodeGen/SelectionDAG/SelectionDAG.cpp @@ -2376,7 +2376,10 @@ void SelectionDAG::computeKnownBits(SDValue Op, KnownBits &Known, break; } case ISD::CTPOP: { - Known.Zero.setBitsFrom(Log2_32(BitWidth)+1); + computeKnownBits(Op.getOperand(0), Known2, DemandedElts, Depth + 1); + // If we know some of the bits are zero, they can't be one. + unsigned PossibleOnes = BitWidth - Known2.Zero.countPopulation(); + Known.Zero.setBitsFrom(Log2_32(PossibleOnes) + 1); break; } case ISD::LOAD: { |
