diff options
Diffstat (limited to 'compiler')
| -rw-r--r-- | compiler/rustc_borrowck/src/diagnostics/region_name.rs | 38 |
1 files changed, 21 insertions, 17 deletions
diff --git a/compiler/rustc_borrowck/src/diagnostics/region_name.rs b/compiler/rustc_borrowck/src/diagnostics/region_name.rs index 15e1066e983..c9de36e9064 100644 --- a/compiler/rustc_borrowck/src/diagnostics/region_name.rs +++ b/compiler/rustc_borrowck/src/diagnostics/region_name.rs @@ -1,6 +1,7 @@ use std::fmt::{self, Display}; use std::iter; +use rustc_data_structures::fx::IndexEntry; use rustc_errors::Diagnostic; use rustc_hir as hir; use rustc_hir::def::{DefKind, Res}; @@ -247,25 +248,28 @@ impl<'tcx> MirBorrowckCtxt<'_, 'tcx> { assert!(self.regioncx.universal_regions().is_universal_region(fr)); - if let Some(value) = self.region_names.try_borrow_mut().unwrap().get(&fr) { - return Some(value.clone()); - } + match self.region_names.borrow_mut().entry(fr) { + IndexEntry::Occupied(precomputed_name) => Some(precomputed_name.get().clone()), + IndexEntry::Vacant(slot) => { + let new_name = self + .give_name_from_error_region(fr) + .or_else(|| self.give_name_if_anonymous_region_appears_in_arguments(fr)) + .or_else(|| self.give_name_if_anonymous_region_appears_in_upvars(fr)) + .or_else(|| self.give_name_if_anonymous_region_appears_in_output(fr)) + .or_else(|| self.give_name_if_anonymous_region_appears_in_yield_ty(fr)) + .or_else(|| self.give_name_if_anonymous_region_appears_in_impl_signature(fr)) + .or_else(|| { + self.give_name_if_anonymous_region_appears_in_arg_position_impl_trait(fr) + }); + + if let Some(new_name) = &new_name { + slot.insert(new_name.clone()); + } + debug!("give_region_a_name: gave name {:?}", new_name); - let value = self - .give_name_from_error_region(fr) - .or_else(|| self.give_name_if_anonymous_region_appears_in_arguments(fr)) - .or_else(|| self.give_name_if_anonymous_region_appears_in_upvars(fr)) - .or_else(|| self.give_name_if_anonymous_region_appears_in_output(fr)) - .or_else(|| self.give_name_if_anonymous_region_appears_in_yield_ty(fr)) - .or_else(|| self.give_name_if_anonymous_region_appears_in_impl_signature(fr)) - .or_else(|| self.give_name_if_anonymous_region_appears_in_arg_position_impl_trait(fr)); - - if let Some(value) = &value { - self.region_names.try_borrow_mut().unwrap().insert(fr, value.clone()); + new_name + } } - - debug!("give_region_a_name: gave name {:?}", value); - value } /// Checks for the case where `fr` maps to something that the |