tags-cache: directly perform a monimal walk for hgtagsfnodescache warming We do something narrower than the path retrieving data. So lets use dedicated code instead. This provides further useful speedup: ### data-env-vars.name = mozilla-try-2023-03-22-zstd-sparse-revlog # benchmark.name = hg.debug.debug-update-cache # bin-env-vars.hg.flavor = default # bin-env-vars.hg.py-re2-module = default # benchmark.variants.pre-state = warm before-this-series: 19.947581 skip-fnode-filter: 18.916804 (-5.17%, -1.03) use-rev-num: 17.493725 (-12.30%, -2.45) this-changesets: 15.919466 (-20.19%, -4.03)

https://bz.mercurial-scm.org/612

  $ hg init repo
  $ cd repo
  $ mkdir src
  $ echo a > src/a.c
  $ hg ci -Ama
  adding src/a.c

  $ hg mv src source
  moving src/a.c to source/a.c

  $ hg ci -Ammove

  $ hg co -C 0
  1 files updated, 0 files merged, 1 files removed, 0 files unresolved

  $ echo new > src/a.c
  $ echo compiled > src/a.o
  $ hg ci -mupdate
  created new head

  $ hg status
  ? src/a.o

  $ hg merge
  merging src/a.c and source/a.c to source/a.c
  0 files updated, 1 files merged, 0 files removed, 0 files unresolved
  (branch merge, don't forget to commit)

  $ hg status
  M source/a.c
  R src/a.c
  ? src/a.o