From 7745175be32cd54e4aa6c9cce6f642f59a34a80f Mon Sep 17 00:00:00 2001 From: Nadav Rotem Date: Wed, 20 Mar 2013 22:53:44 +0000 Subject: When computing the demanded bits of Load SDNodes, make sure that we are looking at the loaded-value operand and not the ptr result (in case of pre-inc loads). rdar://13348420 git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@177596 91177308-0d34-0410-b5e6-96231b3b80d8 --- lib/CodeGen/SelectionDAG/SelectionDAG.cpp | 28 ++++++++++++++++------------ 1 file changed, 16 insertions(+), 12 deletions(-) (limited to 'lib/CodeGen/SelectionDAG/SelectionDAG.cpp') diff --git a/lib/CodeGen/SelectionDAG/SelectionDAG.cpp b/lib/CodeGen/SelectionDAG/SelectionDAG.cpp index 35707e86ce..64244313a3 100644 --- a/lib/CodeGen/SelectionDAG/SelectionDAG.cpp +++ b/lib/CodeGen/SelectionDAG/SelectionDAG.cpp @@ -1917,7 +1917,8 @@ void SelectionDAG::ComputeMaskedBits(SDValue Op, APInt &KnownZero, } case ISD::LOAD: { LoadSDNode *LD = cast(Op); - if (ISD::isZEXTLoad(Op.getNode())) { + // If this is a ZEXTLoad and we are looking at the loaded value. + if (ISD::isZEXTLoad(Op.getNode()) && Op.getResNo() == 0) { EVT VT = LD->getMemoryVT(); unsigned MemBits = VT.getScalarType().getSizeInBits(); KnownZero |= APInt::getHighBitsSet(BitWidth, BitWidth - MemBits); @@ -2287,17 +2288,20 @@ unsigned SelectionDAG::ComputeNumSignBits(SDValue Op, unsigned Depth) const{ break; } - // Handle LOADX separately here. EXTLOAD case will fallthrough. - if (LoadSDNode *LD = dyn_cast(Op)) { - unsigned ExtType = LD->getExtensionType(); - switch (ExtType) { - default: break; - case ISD::SEXTLOAD: // '17' bits known - Tmp = LD->getMemoryVT().getScalarType().getSizeInBits(); - return VTBits-Tmp+1; - case ISD::ZEXTLOAD: // '16' bits known - Tmp = LD->getMemoryVT().getScalarType().getSizeInBits(); - return VTBits-Tmp; + // If we are looking at the loaded value of the SDNode. + if (Op.getResNo() == 0) { + // Handle LOADX separately here. EXTLOAD case will fallthrough. + if (LoadSDNode *LD = dyn_cast(Op)) { + unsigned ExtType = LD->getExtensionType(); + switch (ExtType) { + default: break; + case ISD::SEXTLOAD: // '17' bits known + Tmp = LD->getMemoryVT().getScalarType().getSizeInBits(); + return VTBits-Tmp+1; + case ISD::ZEXTLOAD: // '16' bits known + Tmp = LD->getMemoryVT().getScalarType().getSizeInBits(); + return VTBits-Tmp; + } } } -- cgit v1.2.3-18-g5258