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| author | Timo Teräs <timo.teras@iki.fi> | 2012-10-08 12:25:43 +0300 |
|---|---|---|
| committer | Timo Teräs <timo.teras@iki.fi> | 2012-10-08 12:25:43 +0300 |
| commit | 01d0e4c408ec5096784c59d5f470960fbb2f3753 (patch) | |
| tree | c30722337ed8506cb3831a0eb8e0c89ede427975 /src/solver.c | |
| parent | 831bce5cf90dea266f53a0d82c7371e4652c524c (diff) | |
| download | apk-tools-01d0e4c408ec5096784c59d5f470960fbb2f3753.tar.gz apk-tools-01d0e4c408ec5096784c59d5f470960fbb2f3753.tar.bz2 apk-tools-01d0e4c408ec5096784c59d5f470960fbb2f3753.tar.xz apk-tools-01d0e4c408ec5096784c59d5f470960fbb2f3753.zip | |
solver: optimize backjumping
to be functional when backtracking
Diffstat (limited to 'src/solver.c')
| -rw-r--r-- | src/solver.c | 14 |
1 files changed, 7 insertions, 7 deletions
diff --git a/src/solver.c b/src/solver.c index 75a044b..940282a 100644 --- a/src/solver.c +++ b/src/solver.c @@ -1029,8 +1029,10 @@ static void apply_constraint(struct apk_solver_state *ss, struct apk_dependency } } - if (name->ss.last_touched_decision == 0 || changed) + if (name->ss.last_touched_decision == 0 || changed) { + dep->solver_state = name->ss.last_touched_decision; name->ss.last_touched_decision = ss->num_decisions; + } if (!dep->conflict) { dbg_printf("%s requirers += %d\n", name->name, strength); @@ -1099,12 +1101,10 @@ static void undo_constraint(struct apk_solver_state *ss, struct apk_dependency * } } - /* note: for perfection, we should revert here to the - * *previous* value, but that'd require keeping track - * of it which would require dynamic memory allocations - * or additional solver state field in apk_dependency - * to store it (or hefty recalculations). */ - name->ss.last_touched_decision = 0; + if (dep->solver_state) { + name->ss.last_touched_decision = dep->solver_state; + dep->solver_state = 0; + } if (!dep->conflict) { name->ss.requirers -= strength; |