Let's be always explicit whether we create a library (i.e., an immutable
dependency) or a local `SourceRoot`, since it can have a large impact on
the validation performance in salsa. (we found it the hard way recently,
where the `Default` instance made it quite tricky to spot a bug)
Signed-off-by: Michal Terepeta <michal.terepeta@gmail.com>
When processing a change with added libraries, we used
`Default::default` for `SourceRoot` which sets `is_library` to false.
Since we use `is_library` to decide whether to use low or high
durability, I believe that this caused us to mark many library
dependencies as having low durability and thus increased the size of the
graph that salsa needed to verify on every change.
Based on my initial tests this speeds up the `CrateDefMapQuery` on
rust-analyzer from about ~64ms to ~14ms and reduces the number of
validations for the query from over 60k to about 7k.
Signed-off-by: Michal Terepeta <michal.terepeta@gmail.com>
This change:
- introduces `compute_crate_def_map` query and renames
`CrateDefMap::crate_def_map_query` for consistency,
- annotates `crate_def_map` as `salsa::transparent` and adds a
top-level `crate_def_map` wrapper function around that starts the
profiler and immediately calls into `compute_crate_def_map` query.
This allows us to better understand where we spent the time, in
particular, how much is spent in the recomputaiton and how much in
salsa.
Example output (where we don't actually re-compute anything, but the
query still takes a non-trivial amount of time):
```
211ms - handle_inlay_hints
150ms - get_inlay_hints
150ms - SourceAnalyzer::new
65ms - def_with_body_from_child_node
65ms - analyze_container
65ms - analyze_container
65ms - Module::from_definition
65ms - Module::from_file
65ms - crate_def_map
1ms - parse_macro_query (6 calls)
0ms - raw_items_query (1 calls)
64ms - ???
```
Signed-off-by: Michal Terepeta <michal.terepeta@gmail.com>
