[COMMITTED 037/145] gccrs: Change lookup_hir_path_expr_seg return type

[arthur . cohen]

From: Pierre-Emmanuel Patry <pierre-emmanuel.pa...@embecosm.com>

Make the function's return type optional in order to differentiate
between null pointers and missing value.

gcc/rust/ChangeLog:

        * util/rust-hir-map.cc (Mappings::insert_hir_path_expr_seg): Change
        call site to accomodate the new return type.
        (Mappings::lookup_hir_path_expr_seg): Wrap the function's return type
        with an optional.
        * util/rust-hir-map.h: Update the function's prototype.

Signed-off-by: Pierre-Emmanuel Patry <pierre-emmanuel.pa...@embecosm.com>
---
 gcc/rust/util/rust-hir-map.cc | 6 +++---
 gcc/rust/util/rust-hir-map.h  | 2 +-
 2 files changed, 4 insertions(+), 4 deletions(-)

diff --git a/gcc/rust/util/rust-hir-map.cc b/gcc/rust/util/rust-hir-map.cc
index 80786490f82..c96743a54f8 100644
--- a/gcc/rust/util/rust-hir-map.cc
+++ b/gcc/rust/util/rust-hir-map.cc
@@ -550,19 +550,19 @@ void
 Mappings::insert_hir_path_expr_seg (HIR::PathExprSegment *expr)
 {
   auto id = expr->get_mappings ().get_hirid ();
-  rust_assert (lookup_hir_path_expr_seg (id) == nullptr);
+  rust_assert (!lookup_hir_path_expr_seg (id));
 
   hirPathSegMappings[id] = expr;
   insert_node_to_hir (expr->get_mappings ().get_nodeid (), id);
   insert_location (id, expr->get_locus ());
 }
 
-HIR::PathExprSegment *
+tl::optional<HIR::PathExprSegment *>
 Mappings::lookup_hir_path_expr_seg (HirId id)
 {
   auto it = hirPathSegMappings.find (id);
   if (it == hirPathSegMappings.end ())
-    return nullptr;
+    return tl::nullopt;
 
   return it->second;
 }
diff --git a/gcc/rust/util/rust-hir-map.h b/gcc/rust/util/rust-hir-map.h
index 8d0f652a3d3..c7d0838d400 100644
--- a/gcc/rust/util/rust-hir-map.h
+++ b/gcc/rust/util/rust-hir-map.h
@@ -149,7 +149,7 @@ public:
   tl::optional<HIR::Expr *> lookup_hir_expr (HirId id);
 
   void insert_hir_path_expr_seg (HIR::PathExprSegment *expr);
-  HIR::PathExprSegment *lookup_hir_path_expr_seg (HirId id);
+  tl::optional<HIR::PathExprSegment *> lookup_hir_path_expr_seg (HirId id);
 
   void insert_hir_generic_param (HIR::GenericParam *expr);
   HIR::GenericParam *lookup_hir_generic_param (HirId id);
-- 
2.45.2