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use borrow_check::location::LocationTable;
use borrow_check::nll::constraints::{ConstraintSet, OutlivesConstraint};
use borrow_check::nll::facts::AllFacts;
use borrow_check::nll::region_infer::{RegionTest, TypeTest};
use borrow_check::nll::type_check::Locations;
use borrow_check::nll::universal_regions::UniversalRegions;
use rustc::infer::canonical::QueryRegionConstraint;
use rustc::infer::outlives::obligations::{TypeOutlives, TypeOutlivesDelegate};
use rustc::infer::region_constraints::{GenericKind, VerifyBound};
use rustc::infer::{self, SubregionOrigin};
use rustc::ty::subst::UnpackedKind;
use rustc::ty::{self, TyCtxt};
use syntax_pos::DUMMY_SP;
crate struct ConstraintConversion<'a, 'gcx: 'tcx, 'tcx: 'a> {
tcx: TyCtxt<'a, 'gcx, 'tcx>,
universal_regions: &'a UniversalRegions<'tcx>,
location_table: &'a LocationTable,
region_bound_pairs: &'a [(ty::Region<'tcx>, GenericKind<'tcx>)],
implicit_region_bound: Option<ty::Region<'tcx>>,
param_env: ty::ParamEnv<'tcx>,
locations: Locations,
outlives_constraints: &'a mut ConstraintSet,
type_tests: &'a mut Vec<TypeTest<'tcx>>,
all_facts: &'a mut Option<AllFacts>,
}
impl<'a, 'gcx, 'tcx> ConstraintConversion<'a, 'gcx, 'tcx> {
crate fn new(
tcx: TyCtxt<'a, 'gcx, 'tcx>,
universal_regions: &'a UniversalRegions<'tcx>,
location_table: &'a LocationTable,
region_bound_pairs: &'a [(ty::Region<'tcx>, GenericKind<'tcx>)],
implicit_region_bound: Option<ty::Region<'tcx>>,
param_env: ty::ParamEnv<'tcx>,
locations: Locations,
outlives_constraints: &'a mut ConstraintSet,
type_tests: &'a mut Vec<TypeTest<'tcx>>,
all_facts: &'a mut Option<AllFacts>,
) -> Self {
Self {
tcx,
universal_regions,
location_table,
region_bound_pairs,
implicit_region_bound,
param_env,
locations,
outlives_constraints,
type_tests,
all_facts,
}
}
pub(super) fn convert_all(&mut self, query_constraints: &[QueryRegionConstraint<'tcx>]) {
for query_constraint in query_constraints {
self.convert(query_constraint);
}
}
pub(super) fn convert(&mut self, query_constraint: &QueryRegionConstraint<'tcx>) {
debug!("generate: constraints at: {:#?}", self.locations);
let ConstraintConversion {
tcx,
region_bound_pairs,
implicit_region_bound,
param_env,
..
} = *self;
let ty::OutlivesPredicate(k1, r2) =
query_constraint.no_late_bound_regions().unwrap_or_else(|| {
bug!(
"query_constraint {:?} contained bound regions",
query_constraint,
);
});
match k1.unpack() {
UnpackedKind::Lifetime(r1) => {
let r1_vid = self.to_region_vid(r1);
let r2_vid = self.to_region_vid(r2);
self.add_outlives(r1_vid, r2_vid);
if let Some(all_facts) = &mut self.all_facts {
if let Some(from_location) = self.locations.from_location() {
all_facts.outlives.push((
r1_vid,
r2_vid,
self.location_table.mid_index(from_location),
));
} else {
for location in self.location_table.all_points() {
all_facts.outlives.push((r1_vid, r2_vid, location));
}
}
}
}
UnpackedKind::Type(t1) => {
let origin = infer::RelateParamBound(DUMMY_SP, t1);
TypeOutlives::new(
&mut *self,
tcx,
region_bound_pairs,
implicit_region_bound,
param_env,
).type_must_outlive(origin, t1, r2);
}
}
}
fn verify_to_type_test(
&self,
generic_kind: GenericKind<'tcx>,
region: ty::Region<'tcx>,
bound: VerifyBound<'tcx>,
) -> TypeTest<'tcx> {
let lower_bound = self.to_region_vid(region);
let test = self.verify_bound_to_region_test(&bound);
TypeTest {
generic_kind,
lower_bound,
locations: self.locations,
test,
}
}
fn verify_bound_to_region_test(&self, verify_bound: &VerifyBound<'tcx>) -> RegionTest {
match verify_bound {
VerifyBound::AnyRegion(regions) => RegionTest::IsOutlivedByAnyRegionIn(
regions.iter().map(|r| self.to_region_vid(r)).collect(),
),
VerifyBound::AllRegions(regions) => RegionTest::IsOutlivedByAllRegionsIn(
regions.iter().map(|r| self.to_region_vid(r)).collect(),
),
VerifyBound::AnyBound(bounds) => RegionTest::Any(
bounds
.iter()
.map(|b| self.verify_bound_to_region_test(b))
.collect(),
),
VerifyBound::AllBounds(bounds) => RegionTest::All(
bounds
.iter()
.map(|b| self.verify_bound_to_region_test(b))
.collect(),
),
}
}
fn to_region_vid(&self, r: ty::Region<'tcx>) -> ty::RegionVid {
self.universal_regions.to_region_vid(r)
}
fn add_outlives(&mut self, sup: ty::RegionVid, sub: ty::RegionVid) {
self.outlives_constraints.push(OutlivesConstraint {
locations: self.locations,
sub,
sup,
});
}
fn add_type_test(&mut self, type_test: TypeTest<'tcx>) {
self.type_tests.push(type_test);
}
}
impl<'a, 'b, 'gcx, 'tcx> TypeOutlivesDelegate<'tcx>
for &'a mut ConstraintConversion<'b, 'gcx, 'tcx>
{
fn push_sub_region_constraint(
&mut self,
_origin: SubregionOrigin<'tcx>,
a: ty::Region<'tcx>,
b: ty::Region<'tcx>,
) {
let b = self.universal_regions.to_region_vid(b);
let a = self.universal_regions.to_region_vid(a);
self.add_outlives(b, a);
}
fn push_verify(
&mut self,
_origin: SubregionOrigin<'tcx>,
kind: GenericKind<'tcx>,
a: ty::Region<'tcx>,
bound: VerifyBound<'tcx>,
) {
let type_test = self.verify_to_type_test(kind, a, bound);
self.add_type_test(type_test);
}
}