diff --git a/compiler/rustc_hir_analysis/src/check/region.rs b/compiler/rustc_hir_analysis/src/check/region.rs index ba8124b11fc13..2528adb937b31 100644 --- a/compiler/rustc_hir_analysis/src/check/region.rs +++ b/compiler/rustc_hir_analysis/src/check/region.rs @@ -23,18 +23,11 @@ use tracing::debug; #[derive(Debug, Copy, Clone)] struct Context { - /// The scope that contains any new variables declared, plus its depth in - /// the scope tree. + /// The scope that contains any new variables declared. var_parent: Option, - /// Region parent of expressions, etc., plus its depth in the scope tree. - parent: Option<(Scope, ScopeDepth)>, -} - -impl Context { - fn set_var_parent(&mut self) { - self.var_parent = self.parent.map(|(p, _)| p); - } + /// Region parent of expressions, etc. + parent: Option, } struct ScopeResolutionVisitor<'tcx> { @@ -119,7 +112,7 @@ fn resolve_block<'tcx>(visitor: &mut ScopeResolutionVisitor<'tcx>, blk: &'tcx hi // itself has returned. visitor.enter_node_scope_with_dtor(blk.hir_id.local_id); - visitor.cx.set_var_parent(); + visitor.cx.var_parent = visitor.cx.parent; { // This block should be kept approximately in sync with @@ -138,7 +131,7 @@ fn resolve_block<'tcx>(visitor: &mut ScopeResolutionVisitor<'tcx>, blk: &'tcx hi local_id: blk.hir_id.local_id, data: ScopeData::Remainder(FirstStatementIndex::new(i)), }); - visitor.cx.set_var_parent(); + visitor.cx.var_parent = visitor.cx.parent; visitor.visit_stmt(statement); // We need to back out temporarily to the last enclosing scope // for the `else` block, so that even the temporaries receiving @@ -163,7 +156,7 @@ fn resolve_block<'tcx>(visitor: &mut ScopeResolutionVisitor<'tcx>, blk: &'tcx hi local_id: blk.hir_id.local_id, data: ScopeData::Remainder(FirstStatementIndex::new(i)), }); - visitor.cx.set_var_parent(); + visitor.cx.var_parent = visitor.cx.parent; visitor.visit_stmt(statement) } hir::StmtKind::Item(..) => { @@ -213,7 +206,7 @@ fn resolve_arm<'tcx>(visitor: &mut ScopeResolutionVisitor<'tcx>, arm: &'tcx hir: visitor.terminating_scopes.insert(arm.hir_id.local_id); visitor.enter_node_scope_with_dtor(arm.hir_id.local_id); - visitor.cx.set_var_parent(); + visitor.cx.var_parent = visitor.cx.parent; if let Some(expr) = arm.guard && !has_let_expr(expr) @@ -490,7 +483,7 @@ fn resolve_expr<'tcx>(visitor: &mut ScopeResolutionVisitor<'tcx>, expr: &'tcx hi ScopeData::IfThen }; visitor.enter_scope(Scope { local_id: then.hir_id.local_id, data }); - visitor.cx.set_var_parent(); + visitor.cx.var_parent = visitor.cx.parent; visitor.visit_expr(cond); visitor.visit_expr(then); visitor.cx = expr_cx; @@ -505,7 +498,7 @@ fn resolve_expr<'tcx>(visitor: &mut ScopeResolutionVisitor<'tcx>, expr: &'tcx hi ScopeData::IfThen }; visitor.enter_scope(Scope { local_id: then.hir_id.local_id, data }); - visitor.cx.set_var_parent(); + visitor.cx.var_parent = visitor.cx.parent; visitor.visit_expr(cond); visitor.visit_expr(then); visitor.cx = expr_cx; @@ -545,7 +538,7 @@ fn resolve_expr<'tcx>(visitor: &mut ScopeResolutionVisitor<'tcx>, expr: &'tcx hi // Keep traversing up while we can. match visitor.scope_tree.parent_map.get(&scope) { // Don't cross from closure bodies to their parent. - Some(&(superscope, _)) => match superscope.data { + Some(&superscope) => match superscope.data { ScopeData::CallSite => break, _ => scope = superscope, }, @@ -781,20 +774,16 @@ fn resolve_local<'tcx>( impl<'tcx> ScopeResolutionVisitor<'tcx> { /// Records the current parent (if any) as the parent of `child_scope`. - /// Returns the depth of `child_scope`. - fn record_child_scope(&mut self, child_scope: Scope) -> ScopeDepth { + fn record_child_scope(&mut self, child_scope: Scope) { let parent = self.cx.parent; self.scope_tree.record_scope_parent(child_scope, parent); - // If `child_scope` has no parent, it must be the root node, and so has - // a depth of 1. Otherwise, its depth is one more than its parent's. - parent.map_or(1, |(_p, d)| d + 1) } /// Records the current parent (if any) as the parent of `child_scope`, /// and sets `child_scope` as the new current parent. fn enter_scope(&mut self, child_scope: Scope) { - let child_depth = self.record_child_scope(child_scope); - self.cx.parent = Some((child_scope, child_depth)); + self.record_child_scope(child_scope); + self.cx.parent = Some(child_scope); } fn enter_node_scope_with_dtor(&mut self, id: hir::ItemLocalId) { @@ -855,7 +844,7 @@ impl<'tcx> Visitor<'tcx> for ScopeResolutionVisitor<'tcx> { self.enter_body(body.value.hir_id, |this| { if this.tcx.hir_body_owner_kind(owner_id).is_fn_or_closure() { // The arguments and `self` are parented to the fn. - this.cx.set_var_parent(); + this.cx.var_parent = this.cx.parent; for param in body.params { this.visit_pat(param.pat); } diff --git a/compiler/rustc_middle/src/middle/region.rs b/compiler/rustc_middle/src/middle/region.rs index 66ece8f0e52fd..ba31f775b651e 100644 --- a/compiler/rustc_middle/src/middle/region.rs +++ b/compiler/rustc_middle/src/middle/region.rs @@ -199,8 +199,6 @@ impl Scope { } } -pub type ScopeDepth = u32; - /// The region scope tree encodes information about region relationships. #[derive(Default, Debug, HashStable)] pub struct ScopeTree { @@ -213,7 +211,7 @@ pub struct ScopeTree { /// conditional expression or repeating block. (Note that the /// enclosing scope ID for the block associated with a closure is /// the closure itself.) - pub parent_map: FxIndexMap, + pub parent_map: FxIndexMap, /// Maps from a variable or binding ID to the block in which that /// variable is declared. @@ -328,7 +326,7 @@ pub struct YieldData { } impl ScopeTree { - pub fn record_scope_parent(&mut self, child: Scope, parent: Option<(Scope, ScopeDepth)>) { + pub fn record_scope_parent(&mut self, child: Scope, parent: Option) { debug!("{:?}.parent = {:?}", child, parent); if let Some(p) = parent { @@ -353,7 +351,7 @@ impl ScopeTree { /// Returns the narrowest scope that encloses `id`, if any. pub fn opt_encl_scope(&self, id: Scope) -> Option { - self.parent_map.get(&id).cloned().map(|(p, _)| p) + self.parent_map.get(&id).cloned() } /// Returns the lifetime of the local variable `var_id`, if any. diff --git a/compiler/rustc_middle/src/ty/rvalue_scopes.rs b/compiler/rustc_middle/src/ty/rvalue_scopes.rs index b00c8169a36a7..9bf6e3a759004 100644 --- a/compiler/rustc_middle/src/ty/rvalue_scopes.rs +++ b/compiler/rustc_middle/src/ty/rvalue_scopes.rs @@ -38,7 +38,7 @@ impl RvalueScopes { let mut id = Scope { local_id: expr_id, data: ScopeData::Node }; let mut backwards_incompatible = None; - while let Some(&(p, _)) = region_scope_tree.parent_map.get(&id) { + while let Some(&p) = region_scope_tree.parent_map.get(&id) { match p.data { ScopeData::Destruction => { debug!("temporary_scope({expr_id:?}) = {id:?} [enclosing]");