Merge bitcoin/bitcoin#30857: cluster mempool: extend DepGraph functionalityHEADmaster

0b3ec8c59b2b6d598531cd4e688eb276e597c825 clusterlin: remove Cluster type (Pieter Wuille)
1c24c625105cd62518d2eee7e95c3b1c74ea9923 clusterlin: merge two DepGraph fuzz tests into simulation test (Pieter Wuille)
0606e66fdbb914f984433d8950f0c32b5fb871f3 clusterlin: add DepGraph::RemoveTransactions and support for holes in DepGraph (Pieter Wuille)
75b5d42419ed1286fc9557bc97ec5bac3f9be837 clusterlin: make DepGraph::AddDependency support multiple dependencies at once (Pieter Wuille)
abf50649d13018bf40c5803730a03053737efeee clusterlin: simplify DepGraphFormatter::Ser (Pieter Wuille)
eaab55ffc8102140086297877747b7fa07b419eb clusterlin: rework DepGraphFormatter::Unser (Pieter Wuille)
5901cf7100a75c8131223e23b6c90e0e93611eae clusterlin: abstract out DepGraph::GetReduced{Parents,Children} (Pieter Wuille)

Pull request description:

  Part of cluster mempool: #30289

  This adds:
  * `DepGraph::AddDependencies` to add 0 or more dependencies to a single transaction at once (identical to calling `DepGraph::AddDependency` once for each, but more efficient).
  * `DepGraph::RemoveTransactions` to remove 0 or more transactions from a depgraph.
  * `DepGraph::GetReducedParents` (and `DepGraph::GetReducedChildren`) to get the (reduced) direct parents and children of a transaction in a depgraph.

  After which, the `Cluster` type is removed.

  This is the result of fleshing out the design for the "intermediate layer" ("TxGraph", no PR yet) between the cluster linearization layer and the mempool layer. My earlier thinking was that TxGraph would store `Cluster` objects (vectors of pairs of `FeeFrac`s and sets of parents), and convert them to `DepGraph` on the fly whenever needed. However, after more consideration, it seems better to have TxGraph store `DepGraph` objects, and manipulate them directly without constantly re-creating them. This requires `DepGraph` to have some additional functionality.

  The bulk of the complexity here is the addition of `DepGraph::RemoveTransactions`, which leaves the remaining transactions' positions within the `DepGraph` untouched (we want existing identifiers to remain valid), so this implies that graphs can now have "holes" (positions that are unused, but followed by positions that are used). To enable that, an extension of the fuzz/test serialization format `DepGraphFormatter` is included to deal with such holes.

ACKs for top commit:
  sdaftuar:
    reACK 0b3ec8c59b2b6d598531cd4e688eb276e597c825
  instagibbs:
    reACK 0b3ec8c59b2b6d598531cd4e688eb276e597c825
  ismaelsadeeq:
    reACK 0b3ec8c59b2b6d598531cd4e688eb276e597c825
  glozow:
    ACK 0b3ec8c59b2b6d598531cd4e688eb276e597c825, reviewed range-diff from  aab53ddcd8fcbc3c0be0da9383f8e06abe5badda and `clusterlin_depgraph_sim`

Tree-SHA512: a804b7f26d544c5cb0847322e235c810525cb0607737be6116c3156d582da3ba3352af8ea48e74eed5268f9c3eca63b30181d01b23a6dd0be1b99191f81cceb0

0 files changed, 0 insertions, 0 deletions