void ScheduleDAGSDNodes::BuildSchedUnits() { // During scheduling, the NodeId field of SDNode is used to map SDNodes // to their associated SUnits by holding SUnits table indices. A value // of -1 means the SDNode does not yet have an associated SUnit. unsigned NumNodes = 0; for (SelectionDAG::allnodes_iterator NI = DAG->allnodes_begin(), E = DAG->allnodes_end(); NI != E; ++NI) { NI->setNodeId(-1); ++NumNodes; } // Reserve entries in the vector for each of the SUnits we are creating. This // ensure that reallocation of the vector won't happen, so SUnit*'s won't get // invalidated. // FIXME: Multiply by 2 because we may clone nodes during scheduling. // This is a temporary workaround. SUnits.reserve(NumNodes * 2); // Add all nodes in depth first order. SmallVector<SDNode*, 64> Worklist; SmallPtrSet<SDNode*, 64> Visited; Worklist.push_back(DAG->getRoot().getNode()); Visited.insert(DAG->getRoot().getNode()); SmallVector<SUnit*, 8> CallSUnits; while (!Worklist.empty()) { SDNode *NI = Worklist.pop_back_val(); // Add all operands to the worklist unless they've already been added. for (unsigned i = 0, e = NI->getNumOperands(); i != e; ++i) if (Visited.insert(NI->getOperand(i).getNode())) Worklist.push_back(NI->getOperand(i).getNode()); if (isPassiveNode(NI)) // Leaf node, e.g. a TargetImmediate. continue; // If this node has already been processed, stop now. if (NI->getNodeId() != -1) continue; SUnit *NodeSUnit = newSUnit(NI); // See if anything is glued to this node, if so, add them to glued // nodes. Nodes can have at most one glue input and one glue output. Glue // is required to be the last operand and result of a node. // Scan up to find glued preds. SDNode *N = NI; while (N->getNumOperands() && N->getOperand(N->getNumOperands()-1).getValueType() == MVT::Glue) { N = N->getOperand(N->getNumOperands()-1).getNode(); assert(N->getNodeId() == -1 && "Node already inserted!"); N->setNodeId(NodeSUnit->NodeNum); if (N->isMachineOpcode() && TII->get(N->getMachineOpcode()).isCall()) NodeSUnit->isCall = true; } // Scan down to find any glued succs. N = NI; while (N->getValueType(N->getNumValues()-1) == MVT::Glue) { SDValue GlueVal(N, N->getNumValues()-1); // There are either zero or one users of the Glue result. bool HasGlueUse = false; for (SDNode::use_iterator UI = N->use_begin(), E = N->use_end(); UI != E; ++UI) if (GlueVal.isOperandOf(*UI)) { HasGlueUse = true; assert(N->getNodeId() == -1 && "Node already inserted!"); N->setNodeId(NodeSUnit->NodeNum); N = *UI; if (N->isMachineOpcode() && TII->get(N->getMachineOpcode()).isCall()) NodeSUnit->isCall = true; break; } if (!HasGlueUse) break; } if (NodeSUnit->isCall) CallSUnits.push_back(NodeSUnit); // Schedule zero-latency TokenFactor below any nodes that may increase the // schedule height. Otherwise, ancestors of the TokenFactor may appear to // have false stalls. if (NI->getOpcode() == ISD::TokenFactor) NodeSUnit->isScheduleLow = true; // If there are glue operands involved, N is now the bottom-most node // of the sequence of nodes that are glued together. // Update the SUnit. NodeSUnit->setNode(N); assert(N->getNodeId() == -1 && "Node already inserted!"); N->setNodeId(NodeSUnit->NodeNum); // Compute NumRegDefsLeft. This must be done before AddSchedEdges. InitNumRegDefsLeft(NodeSUnit); // Assign the Latency field of NodeSUnit using target-provided information. computeLatency(NodeSUnit); } // Find all call operands. while (!CallSUnits.empty()) { SUnit *SU = CallSUnits.pop_back_val(); for (const SDNode *SUNode = SU->getNode(); SUNode; SUNode = SUNode->getGluedNode()) { if (SUNode->getOpcode() != ISD::CopyToReg) continue; SDNode *SrcN = SUNode->getOperand(2).getNode(); if (isPassiveNode(SrcN)) continue; // Not scheduled. SUnit *SrcSU = &SUnits[SrcN->getNodeId()]; SrcSU->isCallOp = true; } } }
void ScheduleDAGSDNodes::BuildSchedUnits() { // During scheduling, the NodeId field of SDNode is used to map SDNodes // to their associated SUnits by holding SUnits table indices. A value // of -1 means the SDNode does not yet have an associated SUnit. unsigned NumNodes = 0; for (SelectionDAG::allnodes_iterator NI = DAG->allnodes_begin(), E = DAG->allnodes_end(); NI != E; ++NI) { NI->setNodeId(-1); ++NumNodes; } // Reserve entries in the vector for each of the SUnits we are creating. This // ensure that reallocation of the vector won't happen, so SUnit*'s won't get // invalidated. // FIXME: Multiply by 2 because we may clone nodes during scheduling. // This is a temporary workaround. SUnits.reserve(NumNodes * 2); // Check to see if the scheduler cares about latencies. bool UnitLatencies = ForceUnitLatencies(); // Add all nodes in depth first order. SmallVector<SDNode*, 64> Worklist; SmallPtrSet<SDNode*, 64> Visited; Worklist.push_back(DAG->getRoot().getNode()); Visited.insert(DAG->getRoot().getNode()); while (!Worklist.empty()) { SDNode *NI = Worklist.pop_back_val(); // Add all operands to the worklist unless they've already been added. for (unsigned i = 0, e = NI->getNumOperands(); i != e; ++i) if (Visited.insert(NI->getOperand(i).getNode())) Worklist.push_back(NI->getOperand(i).getNode()); if (isPassiveNode(NI)) // Leaf node, e.g. a TargetImmediate. continue; // If this node has already been processed, stop now. if (NI->getNodeId() != -1) continue; SUnit *NodeSUnit = NewSUnit(NI); // See if anything is flagged to this node, if so, add them to flagged // nodes. Nodes can have at most one flag input and one flag output. Flags // are required to be the last operand and result of a node. // Scan up to find flagged preds. SDNode *N = NI; while (N->getNumOperands() && N->getOperand(N->getNumOperands()-1).getValueType() == MVT::Flag) { N = N->getOperand(N->getNumOperands()-1).getNode(); assert(N->getNodeId() == -1 && "Node already inserted!"); N->setNodeId(NodeSUnit->NodeNum); } // Scan down to find any flagged succs. N = NI; while (N->getValueType(N->getNumValues()-1) == MVT::Flag) { SDValue FlagVal(N, N->getNumValues()-1); // There are either zero or one users of the Flag result. bool HasFlagUse = false; for (SDNode::use_iterator UI = N->use_begin(), E = N->use_end(); UI != E; ++UI) if (FlagVal.isOperandOf(*UI)) { HasFlagUse = true; assert(N->getNodeId() == -1 && "Node already inserted!"); N->setNodeId(NodeSUnit->NodeNum); N = *UI; break; } if (!HasFlagUse) break; } // If there are flag operands involved, N is now the bottom-most node // of the sequence of nodes that are flagged together. // Update the SUnit. NodeSUnit->setNode(N); assert(N->getNodeId() == -1 && "Node already inserted!"); N->setNodeId(NodeSUnit->NodeNum); // Assign the Latency field of NodeSUnit using target-provided information. if (UnitLatencies) NodeSUnit->Latency = 1; else ComputeLatency(NodeSUnit); } }