bendns' repos / rust-analyzer
Unnamed repository; edit this file 'description' to name the repository.
Diffstat (limited to 'crates/hir-ty/src/next_solver/infer/outlives/obligations.rs')
-rw-r--r--crates/hir-ty/src/next_solver/infer/outlives/obligations.rs68
1 files changed, 68 insertions, 0 deletions
diff --git a/crates/hir-ty/src/next_solver/infer/outlives/obligations.rs b/crates/hir-ty/src/next_solver/infer/outlives/obligations.rs
new file mode 100644
index 0000000000..befb2001b1
--- /dev/null
+++ b/crates/hir-ty/src/next_solver/infer/outlives/obligations.rs
@@ -0,0 +1,68 @@
+use ena::undo_log::UndoLogs;
+use rustc_type_ir::{OutlivesPredicate, TypeVisitableExt};
+use tracing::{debug, instrument};
+
+use crate::next_solver::{
+ ArgOutlivesPredicate, GenericArg, Region, RegionOutlivesPredicate, Ty,
+ infer::{InferCtxt, TypeOutlivesConstraint, snapshot::undo_log::UndoLog},
+};
+
+impl<'db> InferCtxt<'db> {
+ pub fn register_outlives_constraint(
+ &self,
+ OutlivesPredicate(arg, r2): ArgOutlivesPredicate<'db>,
+ ) {
+ match arg {
+ GenericArg::Lifetime(r1) => {
+ self.register_region_outlives_constraint(OutlivesPredicate(r1, r2));
+ }
+ GenericArg::Ty(ty1) => {
+ self.register_type_outlives_constraint(ty1, r2);
+ }
+ GenericArg::Const(_) => unreachable!(),
+ }
+ }
+
+ pub fn register_region_outlives_constraint(
+ &self,
+ OutlivesPredicate(r_a, r_b): RegionOutlivesPredicate<'db>,
+ ) {
+ // `'a: 'b` ==> `'b <= 'a`
+ self.sub_regions(r_b, r_a);
+ }
+
+ /// Registers that the given region obligation must be resolved
+ /// from within the scope of `body_id`. These regions are enqueued
+ /// and later processed by regionck, when full type information is
+ /// available (see `region_obligations` field for more
+ /// information).
+ #[instrument(level = "debug", skip(self))]
+ pub fn register_type_outlives_constraint_inner(&self, obligation: TypeOutlivesConstraint<'db>) {
+ let mut inner = self.inner.borrow_mut();
+ inner.undo_log.push(UndoLog::PushTypeOutlivesConstraint);
+ inner.region_obligations.push(obligation);
+ }
+
+ pub fn register_type_outlives_constraint(&self, sup_type: Ty<'db>, sub_region: Region<'db>) {
+ // `is_global` means the type has no params, infer, placeholder, or non-`'static`
+ // free regions. If the type has none of these things, then we can skip registering
+ // this outlives obligation since it has no components which affect lifetime
+ // checking in an interesting way.
+ if sup_type.is_global() {
+ return;
+ }
+
+ debug!(?sup_type, ?sub_region);
+
+ self.register_type_outlives_constraint_inner(TypeOutlivesConstraint {
+ sup_type,
+ sub_region,
+ });
+ }
+
+ pub fn register_region_assumption(&self, assumption: ArgOutlivesPredicate<'db>) {
+ let mut inner = self.inner.borrow_mut();
+ inner.undo_log.push(UndoLog::PushRegionAssumption);
+ inner.region_assumptions.push(assumption);
+ }
+}