Problem
In src/simlin-engine/src/model.rs, set_dependencies_cached invokes all_deps directly, which walks variable ASTs and recomputes dependency closures on every compile. Because this path never consults db::variable_direct_dependencies or db::model_dependency_graph, salsa's backdating mechanism is bypassed during normal compilation. This means edits that keep dependency sets unchanged still pay the full dependency-analysis cost.
Why it matters
This is an optimization opportunity for the incremental compilation pipeline. Salsa's key performance benefit is skipping recomputation when tracked inputs haven't changed ("backdating"). By computing dependencies outside of salsa's tracked functions, the compilation pipeline cannot take advantage of this -- every recompile pays O(variables * AST-depth) even when no dependencies have changed. For large models this is wasted work.
This is not a correctness issue; the current code produces correct results.
Component(s) affected
src/simlin-engine/src/model.rs (set_dependencies_cached, all_deps)src/simlin-engine/src/db.rs (variable_direct_dependencies, model_dependency_graph)
Possible approach
Route the compilation pipeline's dependency analysis through the salsa tracked functions already defined in db.rs (variable_direct_dependencies, model_dependency_graph). This would allow salsa to detect when dependency sets are unchanged and skip downstream recomputation via backdating.
Context
Identified during code review of PR #289.
Problem
In
src/simlin-engine/src/model.rs,set_dependencies_cachedinvokesall_depsdirectly, which walks variable ASTs and recomputes dependency closures on every compile. Because this path never consultsdb::variable_direct_dependenciesordb::model_dependency_graph, salsa's backdating mechanism is bypassed during normal compilation. This means edits that keep dependency sets unchanged still pay the full dependency-analysis cost.Why it matters
This is an optimization opportunity for the incremental compilation pipeline. Salsa's key performance benefit is skipping recomputation when tracked inputs haven't changed ("backdating"). By computing dependencies outside of salsa's tracked functions, the compilation pipeline cannot take advantage of this -- every recompile pays O(variables * AST-depth) even when no dependencies have changed. For large models this is wasted work.
This is not a correctness issue; the current code produces correct results.
Component(s) affected
src/simlin-engine/src/model.rs(set_dependencies_cached,all_deps)src/simlin-engine/src/db.rs(variable_direct_dependencies,model_dependency_graph)Possible approach
Route the compilation pipeline's dependency analysis through the salsa tracked functions already defined in
db.rs(variable_direct_dependencies,model_dependency_graph). This would allow salsa to detect when dependency sets are unchanged and skip downstream recomputation via backdating.Context
Identified during code review of PR #289.