Details | Last modification | View Log | RSS feed
| Rev | Author | Line No. | Line |
|---|---|---|---|
| 14 | pmbaty | 1 | //===---- LatencyPriorityQueue.h - A latency-oriented priority queue ------===// |
| 2 | // |
||
| 3 | // Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions. |
||
| 4 | // See https://llvm.org/LICENSE.txt for license information. |
||
| 5 | // SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception |
||
| 6 | // |
||
| 7 | //===----------------------------------------------------------------------===// |
||
| 8 | // |
||
| 9 | // This file declares the LatencyPriorityQueue class, which is a |
||
| 10 | // SchedulingPriorityQueue that schedules using latency information to |
||
| 11 | // reduce the length of the critical path through the basic block. |
||
| 12 | // |
||
| 13 | //===----------------------------------------------------------------------===// |
||
| 14 | |||
| 15 | #ifndef LLVM_CODEGEN_LATENCYPRIORITYQUEUE_H |
||
| 16 | #define LLVM_CODEGEN_LATENCYPRIORITYQUEUE_H |
||
| 17 | |||
| 18 | #include "llvm/CodeGen/ScheduleDAG.h" |
||
| 19 | #include "llvm/Config/llvm-config.h" |
||
| 20 | |||
| 21 | namespace llvm { |
||
| 22 | class LatencyPriorityQueue; |
||
| 23 | |||
| 24 | /// Sorting functions for the Available queue. |
||
| 25 | struct latency_sort { |
||
| 26 | LatencyPriorityQueue *PQ; |
||
| 27 | explicit latency_sort(LatencyPriorityQueue *pq) : PQ(pq) {} |
||
| 28 | |||
| 29 | bool operator()(const SUnit* LHS, const SUnit* RHS) const; |
||
| 30 | }; |
||
| 31 | |||
| 32 | class LatencyPriorityQueue : public SchedulingPriorityQueue { |
||
| 33 | // SUnits - The SUnits for the current graph. |
||
| 34 | std::vector<SUnit> *SUnits; |
||
| 35 | |||
| 36 | /// NumNodesSolelyBlocking - This vector contains, for every node in the |
||
| 37 | /// Queue, the number of nodes that the node is the sole unscheduled |
||
| 38 | /// predecessor for. This is used as a tie-breaker heuristic for better |
||
| 39 | /// mobility. |
||
| 40 | std::vector<unsigned> NumNodesSolelyBlocking; |
||
| 41 | |||
| 42 | /// Queue - The queue. |
||
| 43 | std::vector<SUnit*> Queue; |
||
| 44 | latency_sort Picker; |
||
| 45 | |||
| 46 | public: |
||
| 47 | LatencyPriorityQueue() : Picker(this) { |
||
| 48 | } |
||
| 49 | |||
| 50 | bool isBottomUp() const override { return false; } |
||
| 51 | |||
| 52 | void initNodes(std::vector<SUnit> &sunits) override { |
||
| 53 | SUnits = &sunits; |
||
| 54 | NumNodesSolelyBlocking.resize(SUnits->size(), 0); |
||
| 55 | } |
||
| 56 | |||
| 57 | void addNode(const SUnit *SU) override { |
||
| 58 | NumNodesSolelyBlocking.resize(SUnits->size(), 0); |
||
| 59 | } |
||
| 60 | |||
| 61 | void updateNode(const SUnit *SU) override { |
||
| 62 | } |
||
| 63 | |||
| 64 | void releaseState() override { |
||
| 65 | SUnits = nullptr; |
||
| 66 | } |
||
| 67 | |||
| 68 | unsigned getLatency(unsigned NodeNum) const { |
||
| 69 | assert(NodeNum < (*SUnits).size()); |
||
| 70 | return (*SUnits)[NodeNum].getHeight(); |
||
| 71 | } |
||
| 72 | |||
| 73 | unsigned getNumSolelyBlockNodes(unsigned NodeNum) const { |
||
| 74 | assert(NodeNum < NumNodesSolelyBlocking.size()); |
||
| 75 | return NumNodesSolelyBlocking[NodeNum]; |
||
| 76 | } |
||
| 77 | |||
| 78 | bool empty() const override { return Queue.empty(); } |
||
| 79 | |||
| 80 | void push(SUnit *U) override; |
||
| 81 | |||
| 82 | SUnit *pop() override; |
||
| 83 | |||
| 84 | void remove(SUnit *SU) override; |
||
| 85 | |||
| 86 | #if !defined(NDEBUG) || defined(LLVM_ENABLE_DUMP) |
||
| 87 | LLVM_DUMP_METHOD void dump(ScheduleDAG *DAG) const override; |
||
| 88 | #endif |
||
| 89 | |||
| 90 | // scheduledNode - As nodes are scheduled, we look to see if there are any |
||
| 91 | // successor nodes that have a single unscheduled predecessor. If so, that |
||
| 92 | // single predecessor has a higher priority, since scheduling it will make |
||
| 93 | // the node available. |
||
| 94 | void scheduledNode(SUnit *SU) override; |
||
| 95 | |||
| 96 | private: |
||
| 97 | void AdjustPriorityOfUnscheduledPreds(SUnit *SU); |
||
| 98 | SUnit *getSingleUnscheduledPred(SUnit *SU); |
||
| 99 | }; |
||
| 100 | } |
||
| 101 | |||
| 102 | #endif |