cocos_lib/cocos/base/job-system/job-system-dummy/DummyJobGraph.cpp

/****************************************************************************
 Copyright (c) 2020-2023 Xiamen Yaji Software Co., Ltd.

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 of this software and associated documentation files (the "Software"), to deal
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#include "DummyJobGraph.h"
#include "base/Macros.h"

#define DUMMY_GRAPH_NODE_CHUNK_SIZE 64

namespace cc {

namespace {
DummyGraphNode *freeList{nullptr};
ccstd::vector<DummyGraphNode *> allocatedChunks;
} // namespace

DummyGraphNode::~DummyGraphNode() {
    delete _callback;
}

void DummyGraphNode::reset() {
    _successors.clear();
    _predecessors.clear();
    delete _callback;
    _callback = nullptr;
}

void DummyGraphNode::succeed(DummyGraphNode *other) {
    CC_ASSERT_NE(this, other);
    // Run after other
    this->_predecessors.emplace(other);
    other->_successors.emplace(this);
}

void DummyGraphNode::precede(DummyGraphNode *other) {
    // Run before other
    other->succeed(this);
}

void DummyGraphNode::allocChunk() {
    CC_ASSERT_NULL(freeList);
    freeList = ccnew DummyGraphNode[DUMMY_GRAPH_NODE_CHUNK_SIZE]();
    allocatedChunks.emplace_back(freeList);
    for (auto i = 0; i < DUMMY_GRAPH_NODE_CHUNK_SIZE - 1; i++) {
        freeList[i]._next = &freeList[i + 1];
    }
    freeList[DUMMY_GRAPH_NODE_CHUNK_SIZE - 1]._next = nullptr;
}

DummyGraphNode *DummyGraphNode::alloc() {
    if (freeList == nullptr) {
        DummyGraphNode::allocChunk();
    }
    auto *p = freeList;
    freeList = freeList->_next;
    p->reset();
    return p;
}

void DummyGraphNode::free(DummyGraphNode *node) {
    node->_next = freeList;
    freeList = node;
}

void DummyGraphNode::freeAll() {
    for (auto *chunk : allocatedChunks) {
        delete[] chunk;
    }
    allocatedChunks.clear();
}

DummyGraph::~DummyGraph() {
    clear();
}

void DummyGraph::clear() {
    for (auto *node : _nodes) {
        DummyGraphNode::free(node);
    }
    _nodes.clear();
}

void DummyGraph::link(size_t precede, size_t after) {
    _nodes[precede]->precede(_nodes[after]);
}

void DummyGraph::run() {
    for (auto *node : _nodes) {
        if (!excuted(node)) {
            walk(node);
        }
    }
    _generation++;
}

void DummyGraph::walk(DummyGraphNode *node) { //NOLINT(misc-no-recursion)
    for (DummyGraphNode *n : node->_predecessors) {
        if (!excuted(n)) {
            walk(n);
        }
    }
    if (!excuted(node)) {
        node->_callback->execute();
        node->_generation++;
    }

    for (DummyGraphNode *n : node->_successors) {
        if (!excuted(n)) {
            walk(n);
        }
    }
}

bool DummyGraph::excuted(DummyGraphNode *n) const {
    return n->_generation != _generation;
}

void DummyJobGraph::makeEdge(uint32_t j1, uint32_t j2) {
    _dummyGraph.link(j1, j2);
}

void DummyJobGraph::run() noexcept {
    _dummyGraph.run();
    _dummyGraph.clear();
}

} // namespace cc