diff options
| -rw-r--r-- | src/librustc/middle/region.rs | 137 |
1 files changed, 70 insertions, 67 deletions
diff --git a/src/librustc/middle/region.rs b/src/librustc/middle/region.rs index c4e20137271..5b6bb3a7b75 100644 --- a/src/librustc/middle/region.rs +++ b/src/librustc/middle/region.rs @@ -65,12 +65,6 @@ pub struct RegionMaps { #[deriving(Clone)] pub struct Context { - sess: Session, - def_map: resolve::DefMap, - - // Generated maps: - region_maps: @mut RegionMaps, - // Scope where variables should be parented to var_parent: Option<ast::NodeId>, @@ -78,6 +72,15 @@ pub struct Context { parent: Option<ast::NodeId>, } +struct RegionResolutionVisitor { + sess: Session, + def_map: resolve::DefMap, + + // Generated maps: + region_maps: @mut RegionMaps, +} + + impl RegionMaps { pub fn relate_free_regions(&mut self, sub: FreeRegion, sup: FreeRegion) { match self.free_region_map.find_mut(&sub) { @@ -318,11 +321,12 @@ impl RegionMaps { } /// Records the current parent (if any) as the parent of `child_id`. -fn parent_to_expr(cx: Context, child_id: ast::NodeId, sp: Span) { +fn parent_to_expr(visitor: &mut RegionResolutionVisitor, + cx: Context, child_id: ast::NodeId, sp: Span) { debug!("region::parent_to_expr(span=%?)", - cx.sess.codemap.span_to_str(sp)); + visitor.sess.codemap.span_to_str(sp)); for parent_id in cx.parent.iter() { - cx.region_maps.record_parent(child_id, *parent_id); + visitor.region_maps.record_parent(child_id, *parent_id); } } @@ -330,12 +334,11 @@ fn resolve_block(visitor: &mut RegionResolutionVisitor, blk: &ast::Block, cx: Context) { // Record the parent of this block. - parent_to_expr(cx, blk.id, blk.span); + parent_to_expr(visitor, cx, blk.id, blk.span); // Descend. let new_cx = Context {var_parent: Some(blk.id), - parent: Some(blk.id), - ..cx}; + parent: Some(blk.id)}; visit::walk_block(visitor, blk, new_cx); } @@ -349,7 +352,7 @@ fn resolve_pat(visitor: &mut RegionResolutionVisitor, pat: @ast::Pat, cx: Context) { assert_eq!(cx.var_parent, cx.parent); - parent_to_expr(cx, pat.id, pat.span); + parent_to_expr(visitor, cx, pat.id, pat.span); visit::walk_pat(visitor, pat, cx); } @@ -362,18 +365,18 @@ fn resolve_stmt(visitor: &mut RegionResolutionVisitor, } ast::StmtExpr(_, stmt_id) | ast::StmtSemi(_, stmt_id) => { - parent_to_expr(cx, stmt_id, stmt.span); + parent_to_expr(visitor, cx, stmt_id, stmt.span); let expr_cx = Context {parent: Some(stmt_id), ..cx}; visit::walk_stmt(visitor, stmt, expr_cx); } - ast::StmtMac(*) => cx.sess.bug("unexpanded macro") + ast::StmtMac(*) => visitor.sess.bug("unexpanded macro") } } fn resolve_expr(visitor: &mut RegionResolutionVisitor, expr: @ast::Expr, cx: Context) { - parent_to_expr(cx, expr.id, expr.span); + parent_to_expr(visitor, cx, expr.id, expr.span); let mut new_cx = cx; new_cx.parent = Some(expr.id); @@ -415,7 +418,7 @@ fn resolve_local(visitor: &mut RegionResolutionVisitor, local: @ast::Local, cx: Context) { assert_eq!(cx.var_parent, cx.parent); - parent_to_expr(cx, local.id, local.span); + parent_to_expr(visitor, cx, local.id, local.span); visit::walk_local(visitor, local, cx); } @@ -439,7 +442,7 @@ fn resolve_fn(visitor: &mut RegionResolutionVisitor, body.id=%?, \ cx.parent=%?)", id, - cx.sess.codemap.span_to_str(sp), + visitor.sess.codemap.span_to_str(sp), body.id, cx.parent); @@ -449,7 +452,7 @@ fn resolve_fn(visitor: &mut RegionResolutionVisitor, ..cx}; match *fk { visit::fk_method(_, _, method) => { - cx.region_maps.record_parent(method.self_id, body.id); + visitor.region_maps.record_parent(method.self_id, body.id); } _ => {} } @@ -470,8 +473,6 @@ fn resolve_fn(visitor: &mut RegionResolutionVisitor, visitor.visit_block(body, body_cx); } -struct RegionResolutionVisitor; - impl Visitor<Context> for RegionResolutionVisitor { fn visit_block(&mut self, b:&Block, cx:Context) { @@ -511,12 +512,13 @@ pub fn resolve_crate(sess: Session, free_region_map: HashMap::new(), cleanup_scopes: HashSet::new(), }; - let cx = Context {sess: sess, - def_map: def_map, - region_maps: region_maps, - parent: None, + let cx = Context {parent: None, var_parent: None}; - let mut visitor = RegionResolutionVisitor; + let mut visitor = RegionResolutionVisitor { + sess: sess, + def_map: def_map, + region_maps: region_maps, + }; visit::walk_crate(&mut visitor, crate, cx); return region_maps; } @@ -733,10 +735,9 @@ impl DetermineRpCtxt { } fn determine_rp_in_item(visitor: &mut DetermineRpVisitor, - item: @ast::item, - cx: @mut DetermineRpCtxt) { - do cx.with(item.id, true) { - visit::walk_item(visitor, item, cx); + item: @ast::item) { + do visitor.cx.with(item.id, true) { + visit::walk_item(visitor, item, ()); } } @@ -745,32 +746,33 @@ fn determine_rp_in_fn(visitor: &mut DetermineRpVisitor, decl: &ast::fn_decl, body: &ast::Block, _: Span, - _: ast::NodeId, - cx: @mut DetermineRpCtxt) { + _: ast::NodeId) { + let cx = visitor.cx; do cx.with(cx.item_id, false) { do cx.with_ambient_variance(rv_contravariant) { for a in decl.inputs.iter() { - visitor.visit_ty(&a.ty, cx); + visitor.visit_ty(&a.ty, ()); } } - visitor.visit_ty(&decl.output, cx); + visitor.visit_ty(&decl.output, ()); let generics = visit::generics_of_fn(fk); - visitor.visit_generics(&generics, cx); - visitor.visit_block(body, cx); + visitor.visit_generics(&generics, ()); + visitor.visit_block(body, ()); } } fn determine_rp_in_ty_method(visitor: &mut DetermineRpVisitor, - ty_m: &ast::TypeMethod, - cx: @mut DetermineRpCtxt) { + ty_m: &ast::TypeMethod) { + let cx = visitor.cx; do cx.with(cx.item_id, false) { - visit::walk_ty_method(visitor, ty_m, cx); + visit::walk_ty_method(visitor, ty_m, ()); } } fn determine_rp_in_ty(visitor: &mut DetermineRpVisitor, - ty: &ast::Ty, - cx: @mut DetermineRpCtxt) { + ty: &ast::Ty) { + let cx = visitor.cx; + // we are only interested in types that will require an item to // be region-parameterized. if cx.item_id is zero, then this type // is not a member of a type defn nor is it a constitutent of an @@ -854,14 +856,14 @@ fn determine_rp_in_ty(visitor: &mut DetermineRpVisitor, match ty.node { ast::ty_box(ref mt) | ast::ty_uniq(ref mt) | ast::ty_vec(ref mt) | ast::ty_rptr(_, ref mt) | ast::ty_ptr(ref mt) => { - visit_mt(visitor, mt, cx); + visit_mt(visitor, mt); } ast::ty_path(ref path, _, _) => { // type parameters are---for now, anyway---always invariant do cx.with_ambient_variance(rv_invariant) { for tp in path.segments.iter().flat_map(|s| s.types.iter()) { - visitor.visit_ty(tp, cx); + visitor.visit_ty(tp, ()); } } } @@ -874,57 +876,58 @@ fn determine_rp_in_ty(visitor: &mut DetermineRpVisitor, // parameters are contravariant do cx.with_ambient_variance(rv_contravariant) { for a in decl.inputs.iter() { - visitor.visit_ty(&a.ty, cx); + visitor.visit_ty(&a.ty, ()); } } - visitor.visit_ty(&decl.output, cx); + visitor.visit_ty(&decl.output, ()); } } _ => { - visit::walk_ty(visitor, ty, cx); + visit::walk_ty(visitor, ty, ()); } } fn visit_mt(visitor: &mut DetermineRpVisitor, - mt: &ast::mt, - cx: @mut DetermineRpCtxt) { + mt: &ast::mt) { + let cx = visitor.cx; // mutability is invariant if mt.mutbl == ast::MutMutable { do cx.with_ambient_variance(rv_invariant) { - visitor.visit_ty(mt.ty, cx); + visitor.visit_ty(mt.ty, ()); } } else { - visitor.visit_ty(mt.ty, cx); + visitor.visit_ty(mt.ty, ()); } } } fn determine_rp_in_struct_field(visitor: &mut DetermineRpVisitor, - cm: @ast::struct_field, - cx: @mut DetermineRpCtxt) { - visit::walk_struct_field(visitor, cm, cx); + cm: @ast::struct_field) { + visit::walk_struct_field(visitor, cm, ()); } -struct DetermineRpVisitor; +struct DetermineRpVisitor { + cx: @mut DetermineRpCtxt +} -impl Visitor<@mut DetermineRpCtxt> for DetermineRpVisitor { +impl Visitor<()> for DetermineRpVisitor { fn visit_fn(&mut self, fk:&fn_kind, fd:&fn_decl, - b:&Block, s:Span, n:NodeId, e:@mut DetermineRpCtxt) { - determine_rp_in_fn(self, fk, fd, b, s, n, e); + b:&Block, s:Span, n:NodeId, _:()) { + determine_rp_in_fn(self, fk, fd, b, s, n); } - fn visit_item(&mut self, i:@item, e:@mut DetermineRpCtxt) { - determine_rp_in_item(self, i, e); + fn visit_item(&mut self, i:@item, _:()) { + determine_rp_in_item(self, i); } - fn visit_ty(&mut self, t:&Ty, e:@mut DetermineRpCtxt) { - determine_rp_in_ty(self, t, e); + fn visit_ty(&mut self, t:&Ty, _:()) { + determine_rp_in_ty(self, t); } - fn visit_ty_method(&mut self, t:&TypeMethod, e:@mut DetermineRpCtxt) { - determine_rp_in_ty_method(self, t, e); + fn visit_ty_method(&mut self, t:&TypeMethod, _:()) { + determine_rp_in_ty_method(self, t); } - fn visit_struct_field(&mut self, s:@struct_field, e:@mut DetermineRpCtxt) { - determine_rp_in_struct_field(self, s, e); + fn visit_struct_field(&mut self, s:@struct_field, _:()) { + determine_rp_in_struct_field(self, s); } } @@ -947,8 +950,8 @@ pub fn determine_rp_in_crate(sess: Session, }; // Gather up the base set, worklist and dep_map - let mut visitor = DetermineRpVisitor; - visit::walk_crate(&mut visitor, crate, cx); + let mut visitor = DetermineRpVisitor { cx: cx }; + visit::walk_crate(&mut visitor, crate, ()); // Propagate indirect dependencies // |