diff options
Diffstat (limited to 'lib/Target/X86/X86ISelDAGToDAG.cpp')
| -rw-r--r-- | lib/Target/X86/X86ISelDAGToDAG.cpp | 74 |
1 files changed, 60 insertions, 14 deletions
diff --git a/lib/Target/X86/X86ISelDAGToDAG.cpp b/lib/Target/X86/X86ISelDAGToDAG.cpp index 4058885..1c0ed7e 100644 --- a/lib/Target/X86/X86ISelDAGToDAG.cpp +++ b/lib/Target/X86/X86ISelDAGToDAG.cpp @@ -140,6 +140,21 @@ namespace { } namespace { + class X86ISelListener : public SelectionDAG::DAGUpdateListener { + SmallSet<SDNode*, 4> Deletes; + public: + explicit X86ISelListener() {} + virtual void NodeDeleted(SDNode *N, SDNode *E) { + Deletes.insert(N); + } + virtual void NodeUpdated(SDNode *N) { + // Ignore updates. + } + bool IsDeleted(SDNode *N) { + return Deletes.count(N); + } + }; + //===--------------------------------------------------------------------===// /// ISel - X86 specific code to select X86 machine instructions for /// SelectionDAG operations. @@ -187,6 +202,7 @@ namespace { bool MatchWrapper(SDValue N, X86ISelAddressMode &AM); bool MatchAddress(SDValue N, X86ISelAddressMode &AM); bool MatchAddressRecursively(SDValue N, X86ISelAddressMode &AM, + X86ISelListener &DeadNodes, unsigned Depth); bool MatchAddressBase(SDValue N, X86ISelAddressMode &AM); bool SelectAddr(SDNode *Op, SDValue N, SDValue &Base, @@ -651,7 +667,8 @@ bool X86DAGToDAGISel::MatchWrapper(SDValue N, X86ISelAddressMode &AM) { /// returning true if it cannot be done. This just pattern matches for the /// addressing mode. bool X86DAGToDAGISel::MatchAddress(SDValue N, X86ISelAddressMode &AM) { - if (MatchAddressRecursively(N, AM, 0)) + X86ISelListener DeadNodes; + if (MatchAddressRecursively(N, AM, DeadNodes, 0)) return true; // Post-processing: Convert lea(,%reg,2) to lea(%reg,%reg), which has @@ -680,6 +697,7 @@ bool X86DAGToDAGISel::MatchAddress(SDValue N, X86ISelAddressMode &AM) { } bool X86DAGToDAGISel::MatchAddressRecursively(SDValue N, X86ISelAddressMode &AM, + X86ISelListener &DeadNodes, unsigned Depth) { bool is64Bit = Subtarget->is64Bit(); DebugLoc dl = N.getDebugLoc(); @@ -845,7 +863,11 @@ bool X86DAGToDAGISel::MatchAddressRecursively(SDValue N, X86ISelAddressMode &AM, // Test if the LHS of the sub can be folded. X86ISelAddressMode Backup = AM; - if (MatchAddressRecursively(N.getNode()->getOperand(0), AM, Depth+1)) { + if (MatchAddressRecursively(N.getNode()->getOperand(0), AM, + DeadNodes, Depth+1) || + // If it is successful but the recursive update causes N to be deleted, + // then it's not safe to continue. + DeadNodes.IsDeleted(N.getNode())) { AM = Backup; break; } @@ -854,6 +876,7 @@ bool X86DAGToDAGISel::MatchAddressRecursively(SDValue N, X86ISelAddressMode &AM, AM = Backup; break; } + int Cost = 0; SDValue RHS = N.getNode()->getOperand(1); // If the RHS involves a register with multiple uses, this @@ -907,13 +930,33 @@ bool X86DAGToDAGISel::MatchAddressRecursively(SDValue N, X86ISelAddressMode &AM, case ISD::ADD: { X86ISelAddressMode Backup = AM; - if (!MatchAddressRecursively(N.getNode()->getOperand(0), AM, Depth+1) && - !MatchAddressRecursively(N.getNode()->getOperand(1), AM, Depth+1)) - return false; + if (!MatchAddressRecursively(N.getNode()->getOperand(0), AM, + DeadNodes, Depth+1)) { + if (DeadNodes.IsDeleted(N.getNode())) + // If it is successful but the recursive update causes N to be deleted, + // then it's not safe to continue. + return true; + if (!MatchAddressRecursively(N.getNode()->getOperand(1), AM, + DeadNodes, Depth+1)) + // If it is successful but the recursive update causes N to be deleted, + // then it's not safe to continue. + return DeadNodes.IsDeleted(N.getNode()); + } + + // Try again after commuting the operands. AM = Backup; - if (!MatchAddressRecursively(N.getNode()->getOperand(1), AM, Depth+1) && - !MatchAddressRecursively(N.getNode()->getOperand(0), AM, Depth+1)) - return false; + if (!MatchAddressRecursively(N.getNode()->getOperand(1), AM, + DeadNodes, Depth+1)) { + if (DeadNodes.IsDeleted(N.getNode())) + // If it is successful but the recursive update causes N to be deleted, + // then it's not safe to continue. + return true; + if (!MatchAddressRecursively(N.getNode()->getOperand(0), AM, + DeadNodes, Depth+1)) + // If it is successful but the recursive update causes N to be deleted, + // then it's not safe to continue. + return DeadNodes.IsDeleted(N.getNode()); + } AM = Backup; // If we couldn't fold both operands into the address at the same time, @@ -935,16 +978,19 @@ bool X86DAGToDAGISel::MatchAddressRecursively(SDValue N, X86ISelAddressMode &AM, if (ConstantSDNode *CN = dyn_cast<ConstantSDNode>(N.getOperand(1))) { X86ISelAddressMode Backup = AM; uint64_t Offset = CN->getSExtValue(); + + // Check to see if the LHS & C is zero. + if (!CurDAG->MaskedValueIsZero(N.getOperand(0), CN->getAPIntValue())) + break; + // Start with the LHS as an addr mode. - if (!MatchAddressRecursively(N.getOperand(0), AM, Depth+1) && + if (!MatchAddressRecursively(N.getOperand(0), AM, DeadNodes, Depth+1) && // Address could not have picked a GV address for the displacement. AM.GV == NULL && // On x86-64, the resultant disp must fit in 32-bits. (!is64Bit || X86::isOffsetSuitableForCodeModel(AM.Disp + Offset, M, - AM.hasSymbolicDisplacement())) && - // Check to see if the LHS & C is zero. - CurDAG->MaskedValueIsZero(N.getOperand(0), CN->getAPIntValue())) { + AM.hasSymbolicDisplacement()))) { AM.Disp += Offset; return false; } @@ -1015,7 +1061,7 @@ bool X86DAGToDAGISel::MatchAddressRecursively(SDValue N, X86ISelAddressMode &AM, CurDAG->RepositionNode(N.getNode(), Shl.getNode()); Shl.getNode()->setNodeId(N.getNode()->getNodeId()); } - CurDAG->ReplaceAllUsesWith(N, Shl); + CurDAG->ReplaceAllUsesWith(N, Shl, &DeadNodes); AM.IndexReg = And; AM.Scale = (1 << ScaleLog); return false; @@ -1066,7 +1112,7 @@ bool X86DAGToDAGISel::MatchAddressRecursively(SDValue N, X86ISelAddressMode &AM, NewSHIFT.getNode()->setNodeId(N.getNode()->getNodeId()); } - CurDAG->ReplaceAllUsesWith(N, NewSHIFT); + CurDAG->ReplaceAllUsesWith(N, NewSHIFT, &DeadNodes); AM.Scale = 1 << ShiftCst; AM.IndexReg = NewAND; |
