https://gcc.gnu.org/g:708920065ea7199781a1cf3670a1a5b2ffdfc00a
commit 708920065ea7199781a1cf3670a1a5b2ffdfc00a
Author: Arthur Cohen <arthur.co...@embecosm.com>
Date: Wed Aug 23 13:51:06 2023 +0200
toplevel: Resolve `use` declarations
gcc/rust/ChangeLog:
* resolve/rust-toplevel-name-resolver-2.0.cc
(TopLevel::insert_or_error_out): New functions.
(TopLevel::handle_use_dec): New function.
(flatten_rebind): Likewise.
(flatten_list): Likewise.
(flatten_glob): Likewise.
(flatten): Likewise.
(TopLevel::visit): Visit various `use` declaration nodes.
* resolve/rust-toplevel-name-resolver-2.0.h: Declare functions and
visitors.
Diff:
---
.../resolve/rust-toplevel-name-resolver-2.0.cc | 187 ++++++++++++++++++++-
gcc/rust/resolve/rust-toplevel-name-resolver-2.0.h | 11 ++
2 files changed, 194 insertions(+), 4 deletions(-)
diff --git a/gcc/rust/resolve/rust-toplevel-name-resolver-2.0.cc
b/gcc/rust/resolve/rust-toplevel-name-resolver-2.0.cc
index b9d0bc7c0ac9..46113a8a46b3 100644
--- a/gcc/rust/resolve/rust-toplevel-name-resolver-2.0.cc
+++ b/gcc/rust/resolve/rust-toplevel-name-resolver-2.0.cc
@@ -17,6 +17,7 @@
// <http://www.gnu.org/licenses/>.
#include "rust-toplevel-name-resolver-2.0.h"
+#include "optional.h"
#include "rust-ast-full.h"
#include "rust-hir-map.h"
#include "rust-attribute-values.h"
@@ -33,11 +34,16 @@ void
TopLevel::insert_or_error_out (const Identifier &identifier, const T &node,
Namespace ns)
{
- auto loc = node.get_locus ();
- auto node_id = node.get_node_id ();
+ insert_or_error_out (identifier, node.get_locus (), node.get_node_id (), ns);
+}
+void
+TopLevel::insert_or_error_out (const Identifier &identifier,
+ const location_t &locus, const NodeId &node_id,
+ Namespace ns)
+{
// keep track of each node's location to provide useful errors
- node_locations.emplace (node_id, loc);
+ node_locations.emplace (node_id, locus);
auto result = ctx.insert (identifier, node_id, ns);
@@ -46,7 +52,7 @@ TopLevel::insert_or_error_out (const Identifier &identifier,
const T &node,
// can we do something like check if the node id is the same? if it is
the
// same, it's not an error, just the resolver running multiple times?
- rich_location rich_loc (line_table, loc);
+ rich_location rich_loc (line_table, locus);
rich_loc.add_range (node_locations[result.error ().existing]);
rust_error_at (rich_loc, ErrorCode::E0428, "%qs defined multiple times",
@@ -308,5 +314,178 @@ TopLevel::visit (AST::ConstantItem &const_item)
ctx.scoped (Rib::Kind::ConstantItem, const_item.get_node_id (), expr_vis);
}
+bool
+TopLevel::handle_use_dec (AST::SimplePath path)
+{
+ // TODO: Glob imports can get shadowed by regular imports and regular items.
+ // So we need to store them in a specific way in the ForeverStack - which can
+ // also probably be used by labels and macros etc. Like store it as a
+ // `Shadowable(NodeId)` instead of just a `NodeId`
+
+ auto locus = path.get_final_segment ().get_locus ();
+ auto declared_name = path.get_final_segment ().as_string ();
+
+ // in what namespace do we perform path resolution? All of them? see which
one
+ // matches? Error out on ambiguities?
+ // so, apparently, for each one that matches, add it to the proper namespace
+ // :(
+
+ auto found = false;
+
+ auto resolve_and_insert = [this, &found, &declared_name,
+ locus] (Namespace ns,
+ const AST::SimplePath &path) {
+ tl::optional<NodeId> resolved = tl::nullopt;
+
+ // FIXME: resolve_path needs to return an `expected<NodeId, Error>` so
+ // that we can improve it with hints or location or w/ever. and maybe
+ // only emit it the first time.
+ switch (ns)
+ {
+ case Namespace::Values:
+ resolved = ctx.values.resolve_path (path.get_segments ());
+ break;
+ case Namespace::Types:
+ resolved = ctx.types.resolve_path (path.get_segments ());
+ break;
+ case Namespace::Macros:
+ resolved = ctx.macros.resolve_path (path.get_segments ());
+ break;
+ case Namespace::Labels:
+ // TODO: Is that okay?
+ rust_unreachable ();
+ }
+
+ // FIXME: Ugly
+ (void) resolved.map ([this, &found, &declared_name, locus, ns] (NodeId id)
{
+ found = true;
+
+ // what do we do with the id?
+ insert_or_error_out (declared_name, locus, id, ns);
+
+ return id;
+ });
+ };
+
+ // do this for all namespaces (even Labels?)
+
+ resolve_and_insert (Namespace::Values, path);
+ resolve_and_insert (Namespace::Types, path);
+ resolve_and_insert (Namespace::Macros, path);
+
+ // TODO: No labels? No, right?
+
+ return found;
+}
+
+static void
+flatten_rebind (const AST::UseTreeRebind &glob,
+ std::vector<AST::SimplePath> &paths);
+static void
+flatten_list (const AST::UseTreeList &glob,
+ std::vector<AST::SimplePath> &paths);
+static void
+flatten_glob (const AST::UseTreeGlob &glob,
+ std::vector<AST::SimplePath> &paths);
+
+static void
+flatten (const AST::UseTree *tree, std::vector<AST::SimplePath> &paths)
+{
+ switch (tree->get_kind ())
+ {
+ case AST::UseTree::Rebind: {
+ auto rebind = static_cast<const AST::UseTreeRebind *> (tree);
+ flatten_rebind (*rebind, paths);
+ break;
+ }
+ case AST::UseTree::List: {
+ auto list = static_cast<const AST::UseTreeList *> (tree);
+ flatten_list (*list, paths);
+ break;
+ }
+ case AST::UseTree::Glob: {
+ rust_sorry_at (tree->get_locus (), "cannot resolve glob imports yet");
+ auto glob = static_cast<const AST::UseTreeGlob *> (tree);
+ flatten_glob (*glob, paths);
+ break;
+ }
+ break;
+ }
+}
+
+static void
+flatten_rebind (const AST::UseTreeRebind &rebind,
+ std::vector<AST::SimplePath> &paths)
+{
+ auto path = rebind.get_path ();
+
+ // FIXME: Do we want to emplace the rebind here as well?
+ if (rebind.has_identifier ())
+ {
+ auto rebind_path = path;
+ auto new_seg = rebind.get_identifier ();
+
+ // Add the identifier as a new path
+ rebind_path.get_segments ().back ()
+ = AST::SimplePathSegment (new_seg.as_string (), UNDEF_LOCATION);
+
+ paths.emplace_back (rebind_path);
+ }
+ else
+ {
+ paths.emplace_back (path);
+ }
+}
+
+static void
+flatten_list (const AST::UseTreeList &list, std::vector<AST::SimplePath>
&paths)
+{
+ auto prefix = AST::SimplePath::create_empty ();
+ if (list.has_path ())
+ prefix = list.get_path ();
+
+ for (const auto &tree : list.get_trees ())
+ {
+ auto sub_paths = std::vector<AST::SimplePath> ();
+ flatten (tree.get (), sub_paths);
+
+ for (auto &sub_path : sub_paths)
+ {
+ auto new_path = prefix;
+ std::copy (sub_path.get_segments ().begin (),
+ sub_path.get_segments ().end (),
+ std::back_inserter (new_path.get_segments ()));
+
+ paths.emplace_back (new_path);
+ }
+ }
+}
+
+static void
+flatten_glob (const AST::UseTreeGlob &glob, std::vector<AST::SimplePath>
&paths)
+{
+ if (glob.has_path ())
+ paths.emplace_back (glob.get_path ());
+}
+
+void
+TopLevel::visit (AST::UseDeclaration &use)
+{
+ auto paths = std::vector<AST::SimplePath> ();
+
+ // FIXME: How do we handle `use foo::{self}` imports? Some beforehand
cleanup?
+ // How do we handle module imports in general? Should they get added to all
+ // namespaces?
+
+ const auto &tree = use.get_tree ();
+ flatten (tree.get (), paths);
+
+ for (auto &path : paths)
+ if (!handle_use_dec (path))
+ rust_error_at (path.get_final_segment ().get_locus (), ErrorCode::E0433,
+ "could not resolve import %qs",
+ path.as_string ().c_str ());
+}
+
} // namespace Resolver2_0
} // namespace Rust
diff --git a/gcc/rust/resolve/rust-toplevel-name-resolver-2.0.h
b/gcc/rust/resolve/rust-toplevel-name-resolver-2.0.h
index 95187d7b3fdb..996899b0848f 100644
--- a/gcc/rust/resolve/rust-toplevel-name-resolver-2.0.h
+++ b/gcc/rust/resolve/rust-toplevel-name-resolver-2.0.h
@@ -53,6 +53,9 @@ private:
template <typename T>
void insert_or_error_out (const Identifier &identifier, const T &node,
Namespace ns);
+ void insert_or_error_out (const Identifier &identifier,
+ const location_t &locus, const NodeId &id,
+ Namespace ns);
// FIXME: Do we move these to our mappings?
std::unordered_map<NodeId, location_t> node_locations;
@@ -73,6 +76,14 @@ private:
void visit (AST::Union &union_item) override;
void visit (AST::ConstantItem &const_item) override;
void visit (AST::ExternCrate &crate) override;
+
+ // FIXME: Documentation
+ // Call this on all the paths of a UseDec - so each flattened path in a
+ // UseTreeList for example
+ // FIXME: Should that return `found`?
+ bool handle_use_dec (AST::SimplePath path);
+
+ void visit (AST::UseDeclaration &use) override;
};
} // namespace Resolver2_0
