[COMMITTED 039/145] gccrs: Change lookup_hir_type return type with an optional

[arthur . cohen]

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

Wrap the function's return type with an optional in order to tell
appart a null pointer from a missing value.

gcc/rust/ChangeLog:

        * util/rust-hir-map.cc (Mappings::insert_hir_type): Change call site
        to accomodate the new return type.
        (Mappings::lookup_hir_type): Change the function's return type.
        * 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 c3929d8f3ce..ae11e67a57b 100644
--- a/gcc/rust/util/rust-hir-map.cc
+++ b/gcc/rust/util/rust-hir-map.cc
@@ -592,18 +592,18 @@ void
 Mappings::insert_hir_type (HIR::Type *type)
 {
   auto id = type->get_mappings ().get_hirid ();
-  rust_assert (lookup_hir_type (id) == nullptr);
+  rust_assert (!lookup_hir_type (id));
 
   hirTypeMappings[id] = type;
   insert_node_to_hir (type->get_mappings ().get_nodeid (), id);
 }
 
-HIR::Type *
+tl::optional<HIR::Type *>
 Mappings::lookup_hir_type (HirId id)
 {
   auto it = hirTypeMappings.find (id);
   if (it == hirTypeMappings.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 d04232f3d5d..e4f47852ed9 100644
--- a/gcc/rust/util/rust-hir-map.h
+++ b/gcc/rust/util/rust-hir-map.h
@@ -155,7 +155,7 @@ public:
   tl::optional<HIR::GenericParam *> lookup_hir_generic_param (HirId id);
 
   void insert_hir_type (HIR::Type *type);
-  HIR::Type *lookup_hir_type (HirId id);
+  tl::optional<HIR::Type *> lookup_hir_type (HirId id);
 
   void insert_hir_stmt (HIR::Stmt *stmt);
   HIR::Stmt *lookup_hir_stmt (HirId id);
-- 
2.45.2