LatencyPriorityQueue.h revision 198892
131921Sbrian//===---- LatencyPriorityQueue.h - A latency-oriented priority queue ------===// 231921Sbrian// 331921Sbrian// The LLVM Compiler Infrastructure 431921Sbrian// 531921Sbrian// This file is distributed under the University of Illinois Open Source 631921Sbrian// License. See LICENSE.TXT for details. 731921Sbrian// 831921Sbrian//===----------------------------------------------------------------------===// 931921Sbrian// 1031921Sbrian// This file declares the LatencyPriorityQueue class, which is a 1131921Sbrian// SchedulingPriorityQueue that schedules using latency information to 1231921Sbrian// reduce the length of the critical path through the basic block. 1331921Sbrian// 1431921Sbrian//===----------------------------------------------------------------------===// 1531921Sbrian 1631921Sbrian#ifndef LATENCY_PRIORITY_QUEUE_H 1731921Sbrian#define LATENCY_PRIORITY_QUEUE_H 1831921Sbrian 1931921Sbrian#include "llvm/CodeGen/ScheduleDAG.h" 2031921Sbrian#include "llvm/ADT/PriorityQueue.h" 2131921Sbrian 2231921Sbriannamespace llvm { 2331921Sbrian class LatencyPriorityQueue; 2431921Sbrian 2531921Sbrian /// Sorting functions for the Available queue. 2636465Sbrian struct latency_sort : public std::binary_function<SUnit*, SUnit*, bool> { 2730715Sbrian LatencyPriorityQueue *PQ; 2830715Sbrian explicit latency_sort(LatencyPriorityQueue *pq) : PQ(pq) {} 2931196Sbrian 3030715Sbrian bool operator()(const SUnit* left, const SUnit* right) const; 3131121Sbrian }; 3236285Sbrian 3334539Sbrian class LatencyPriorityQueue : public SchedulingPriorityQueue { 3431196Sbrian // SUnits - The SUnits for the current graph. 3530715Sbrian std::vector<SUnit> *SUnits; 3630715Sbrian 3730715Sbrian /// NumNodesSolelyBlocking - This vector contains, for every node in the 3830715Sbrian /// Queue, the number of nodes that the node is the sole unscheduled 3930715Sbrian /// predecessor for. This is used as a tie-breaker heuristic for better 4030715Sbrian /// mobility. 4136453Sbrian std::vector<unsigned> NumNodesSolelyBlocking; 4230715Sbrian 4330715Sbrian /// IgnoreAntiDep - Ignore anti-dependencies 4430715Sbrian bool IgnoreAntiDep; 4530715Sbrian 4630715Sbrian /// Queue - The queue. 4730715Sbrian PriorityQueue<SUnit*, std::vector<SUnit*>, latency_sort> Queue; 4831343Sbrian 4936285Sbrianpublic: 5031343Sbrian LatencyPriorityQueue() : IgnoreAntiDep(false), Queue(latency_sort(this)) { 5130715Sbrian } 5231196Sbrian 5336285Sbrian void setIgnoreAntiDep(bool ignore) { 5436285Sbrian IgnoreAntiDep = ignore; 5536285Sbrian } 5636285Sbrian 5731196Sbrian void initNodes(std::vector<SUnit> &sunits) { 5836285Sbrian SUnits = &sunits; 5936285Sbrian NumNodesSolelyBlocking.resize(SUnits->size(), 0); 6036285Sbrian } 6136285Sbrian 6236285Sbrian void addNode(const SUnit *SU) { 6336285Sbrian NumNodesSolelyBlocking.resize(SUnits->size(), 0); 6436285Sbrian } 6536285Sbrian 6636285Sbrian void updateNode(const SUnit *SU) { 6736285Sbrian } 6836285Sbrian 6936285Sbrian void releaseState() { 7036285Sbrian SUnits = 0; 7136285Sbrian } 7236285Sbrian 7336285Sbrian unsigned getLatency(unsigned NodeNum) const { 7436285Sbrian assert(NodeNum < (*SUnits).size()); 7536465Sbrian return (*SUnits)[NodeNum].getHeight(IgnoreAntiDep); 7636465Sbrian } 7736285Sbrian 7836285Sbrian unsigned getNumSolelyBlockNodes(unsigned NodeNum) const { 7936465Sbrian assert(NodeNum < NumNodesSolelyBlocking.size()); 8036465Sbrian return NumNodesSolelyBlocking[NodeNum]; 8136285Sbrian } 8236285Sbrian 8336285Sbrian unsigned size() const { return Queue.size(); } 8436285Sbrian 8536285Sbrian bool empty() const { return Queue.empty(); } 8636285Sbrian 8731196Sbrian virtual void push(SUnit *U) { 8836285Sbrian push_impl(U); 8931196Sbrian } 9036285Sbrian void push_impl(SUnit *U); 9136285Sbrian 9236285Sbrian void push_all(const std::vector<SUnit *> &Nodes) { 9331196Sbrian for (unsigned i = 0, e = Nodes.size(); i != e; ++i) 9436285Sbrian push_impl(Nodes[i]); 9531196Sbrian } 9631203Sbrian 9736285Sbrian SUnit *pop() { 9836285Sbrian if (empty()) return NULL; 9931203Sbrian SUnit *V = Queue.top(); 10036285Sbrian Queue.pop(); 10131203Sbrian return V; 10236285Sbrian } 10336285Sbrian 10436285Sbrian void remove(SUnit *SU) { 10536285Sbrian assert(!Queue.empty() && "Not in queue!"); 10636285Sbrian Queue.erase_one(SU); 10736285Sbrian } 10836285Sbrian 10936285Sbrian // ScheduledNode - As nodes are scheduled, we look to see if there are any 11036285Sbrian // successor nodes that have a single unscheduled predecessor. If so, that 11136285Sbrian // single predecessor has a higher priority, since scheduling it will make 11236285Sbrian // the node available. 11336285Sbrian void ScheduledNode(SUnit *Node); 11431203Sbrian 115private: 116 void AdjustPriorityOfUnscheduledPreds(SUnit *SU); 117 SUnit *getSingleUnscheduledPred(SUnit *SU); 118 }; 119} 120 121#endif 122