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| author | Chris Lattner <sabre@nondot.org> | 2006-05-05 22:32:12 +0000 |
|---|---|---|
| committer | Chris Lattner <sabre@nondot.org> | 2006-05-05 22:32:12 +0000 |
| commit | fe8babf689c624c53d03f5629324b049b5327a6e (patch) | |
| tree | 5db2b9e4d206344ddb6b245b3134548828ccb668 | |
| parent | 35c3913328b254871731f1f5cc092c303a2cd378 (diff) | |
| download | external_llvm-fe8babf689c624c53d03f5629324b049b5327a6e.zip external_llvm-fe8babf689c624c53d03f5629324b049b5327a6e.tar.gz external_llvm-fe8babf689c624c53d03f5629324b049b5327a6e.tar.bz2 | |
Implement ComputeMaskedBits/SimplifyDemandedBits for ISD::TRUNCATE
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@28135 91177308-0d34-0410-b5e6-96231b3b80d8
| -rw-r--r-- | lib/CodeGen/SelectionDAG/TargetLowering.cpp | 18 |
1 files changed, 18 insertions, 0 deletions
diff --git a/lib/CodeGen/SelectionDAG/TargetLowering.cpp b/lib/CodeGen/SelectionDAG/TargetLowering.cpp index 041d91e..30ef672 100644 --- a/lib/CodeGen/SelectionDAG/TargetLowering.cpp +++ b/lib/CodeGen/SelectionDAG/TargetLowering.cpp @@ -607,6 +607,16 @@ bool TargetLowering::SimplifyDemandedBits(SDOperand Op, uint64_t DemandedMask, assert((KnownZero & KnownOne) == 0 && "Bits known to be one AND zero?"); break; } + case ISD::TRUNCATE: { + if (SimplifyDemandedBits(Op.getOperand(0), DemandedMask, + KnownZero, KnownOne, TLO, Depth+1)) + return true; + assert((KnownZero & KnownOne) == 0 && "Bits known to be one AND zero?"); + uint64_t OutMask = MVT::getIntVTBitMask(Op.getValueType()); + KnownZero &= OutMask; + KnownOne &= OutMask; + break; + } case ISD::AssertZext: { MVT::ValueType VT = cast<VTSDNode>(Op.getOperand(1))->getVT(); uint64_t InMask = MVT::getIntVTBitMask(VT); @@ -864,6 +874,14 @@ void TargetLowering::ComputeMaskedBits(SDOperand Op, uint64_t Mask, KnownZero, KnownOne, Depth+1); return; } + case ISD::TRUNCATE: { + ComputeMaskedBits(Op.getOperand(0), Mask, KnownZero, KnownOne, Depth+1); + assert((KnownZero & KnownOne) == 0 && "Bits known to be one AND zero?"); + uint64_t OutMask = MVT::getIntVTBitMask(Op.getValueType()); + KnownZero &= OutMask; + KnownOne &= OutMask; + break; + } case ISD::AssertZext: { MVT::ValueType VT = cast<VTSDNode>(Op.getOperand(1))->getVT(); uint64_t InMask = MVT::getIntVTBitMask(VT); |