res-dep-graph.hpp File Reference

DependencyGraph — TBB flow-graph over (level, slanted-degree) cells of a Schreyer-frame resolution. More...

#include "m2tbb.hpp"

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Detailed Description

DependencyGraph — TBB flow-graph over (level, slanted-degree) cells of a Schreyer-frame resolution.

Note

AI-generated documentation. Verify against the source before relying on it.

Declares the parallel scheduler the F4 resolution driver uses to run multiple homological degrees concurrently while respecting the fill-matrix dependency that cell (level, slanted_degree) requires both (level - 1, slanted_degree) and (level, slanted_degree - 1) to have completed first; the minimal-Betti pass adds an extra edge from (level + 1, slanted_degree - 1)'s rank node into the current cell's Betti node. Each cell is a Node carrying a mFillAndReduceNode, mRankNode, and optional mMinimalBettiNode, all tbb::flow::continue_node<continue_msg> so a node fires once all its predecessors have. addVertex / addFillMatrixEdge / addMinimalBettiEdge wire the graph, startComputation triggers the root (mVertices[0]'s fill-and-reduce node, which is assumed to be the top of the dependency tree), and waitForCompletion blocks on the whole frontier. The free function makeDependencyGraph(G, nlevels, nslanted_degrees, doMinimalBetti) constructs the standard layout.

The 2-D grid is linearised via getIndex(lev, sldeg, nlevels, nslanted_degrees) = lev + sldeg * nlevels, with the matching inverse getPair. The whole header is #ifdef WITH_TBB- gated; on builds without TBB the parallel layer compiles to nothing and SchreyerFrame::minimalBettiNumbers falls back to its serial computeRanks path. The parallelizeByDegree flag plumbed through F4ResComputation is a single on/off switch — when true, SchreyerFrame::minimalBettiNumbers builds and triggers this graph; when false, it skips the dep graph entirely and runs the serial path. The graph also carries a topologicalSort walker (used for debug printing via print()) and a std::mutex mMutex for the single-vertex edits done off the TBB thread pool.

See also

res-f4-computation.hpp

res-schreyer-frame.hpp

m2tbb.hpp

Definition in file res-dep-graph.hpp.