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Inline and remove some functions.

These are all functions with a single callsite, where having a separate
function does nothing to help with readability. These changes make the
code a little shorter and easier to read.
This commit is contained in:
Nicholas Nethercote 2024-08-28 10:13:17 +10:00
parent 8235af07d2
commit 48064d4498
10 changed files with 341 additions and 392 deletions

View file

@ -381,7 +381,29 @@ impl<'tcx> crate::MirPass<'tcx> for SimplifyLocals {
fn run_pass(&self, tcx: TyCtxt<'tcx>, body: &mut Body<'tcx>) {
trace!("running SimplifyLocals on {:?}", body.source);
simplify_locals(body, tcx);
// First, we're going to get a count of *actual* uses for every `Local`.
let mut used_locals = UsedLocals::new(body);
// Next, we're going to remove any `Local` with zero actual uses. When we remove those
// `Locals`, we're also going to subtract any uses of other `Locals` from the `used_locals`
// count. For example, if we removed `_2 = discriminant(_1)`, then we'll subtract one from
// `use_counts[_1]`. That in turn might make `_1` unused, so we loop until we hit a
// fixedpoint where there are no more unused locals.
remove_unused_definitions_helper(&mut used_locals, body);
// Finally, we'll actually do the work of shrinking `body.local_decls` and remapping the
// `Local`s.
let map = make_local_map(&mut body.local_decls, &used_locals);
// Only bother running the `LocalUpdater` if we actually found locals to remove.
if map.iter().any(Option::is_none) {
// Update references to all vars and tmps now
let mut updater = LocalUpdater { map, tcx };
updater.visit_body_preserves_cfg(body);
body.local_decls.shrink_to_fit();
}
}
}
@ -397,30 +419,6 @@ pub(super) fn remove_unused_definitions<'tcx>(body: &mut Body<'tcx>) {
remove_unused_definitions_helper(&mut used_locals, body);
}
fn simplify_locals<'tcx>(body: &mut Body<'tcx>, tcx: TyCtxt<'tcx>) {
// First, we're going to get a count of *actual* uses for every `Local`.
let mut used_locals = UsedLocals::new(body);
// Next, we're going to remove any `Local` with zero actual uses. When we remove those
// `Locals`, we're also going to subtract any uses of other `Locals` from the `used_locals`
// count. For example, if we removed `_2 = discriminant(_1)`, then we'll subtract one from
// `use_counts[_1]`. That in turn might make `_1` unused, so we loop until we hit a
// fixedpoint where there are no more unused locals.
remove_unused_definitions_helper(&mut used_locals, body);
// Finally, we'll actually do the work of shrinking `body.local_decls` and remapping the `Local`s.
let map = make_local_map(&mut body.local_decls, &used_locals);
// Only bother running the `LocalUpdater` if we actually found locals to remove.
if map.iter().any(Option::is_none) {
// Update references to all vars and tmps now
let mut updater = LocalUpdater { map, tcx };
updater.visit_body_preserves_cfg(body);
body.local_decls.shrink_to_fit();
}
}
/// Construct the mapping while swapping out unused stuff out from the `vec`.
fn make_local_map<V>(
local_decls: &mut IndexVec<Local, V>,