[COMMITTED 024/145] gccrs: Change return type for lookup_hir_impl_block

[arthur . cohen]

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

Change the return type to an optiona. This allows to differentiate
between missing hir impl block and null pointers.

gcc/rust/ChangeLog:

        * typecheck/rust-type-util.cc (query_type): Change call to the function
        in order to accomodate the new return type.
        * util/rust-hir-map.cc (Mappings::lookup_hir_impl_block): Change the
        function's return type to 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/typecheck/rust-type-util.cc | 8 ++++----
 gcc/rust/util/rust-hir-map.cc        | 6 +++---
 gcc/rust/util/rust-hir-map.h         | 2 +-
 3 files changed, 8 insertions(+), 8 deletions(-)

diff --git a/gcc/rust/typecheck/rust-type-util.cc 
b/gcc/rust/typecheck/rust-type-util.cc
index 9a777863c2c..af38acd0c32 100644
--- a/gcc/rust/typecheck/rust-type-util.cc
+++ b/gcc/rust/typecheck/rust-type-util.cc
@@ -75,15 +75,15 @@ query_type (HirId reference, TyTy::BaseType **result)
     = mappings.lookup_hir_implitem (reference, &parent_impl_id);
   if (impl_item != nullptr)
     {
-      HIR::ImplBlock *impl_block
-       = mappings.lookup_hir_impl_block (parent_impl_id);
-      rust_assert (impl_block != nullptr);
+      auto impl_block = mappings.lookup_hir_impl_block (parent_impl_id);
+      rust_assert (impl_block);
 
       // found an impl item
       rust_debug_loc (impl_item->get_locus (), "resolved impl-item {%u} to",
                      reference);
 
-      *result = TypeCheckItem::ResolveImplItem (*impl_block, *impl_item);
+      *result
+       = TypeCheckItem::ResolveImplItem (*impl_block.value (), *impl_item);
       context->query_completed (reference);
       return true;
     }
diff --git a/gcc/rust/util/rust-hir-map.cc b/gcc/rust/util/rust-hir-map.cc
index 184ab13494d..a5b1daf04c1 100644
--- a/gcc/rust/util/rust-hir-map.cc
+++ b/gcc/rust/util/rust-hir-map.cc
@@ -468,7 +468,7 @@ void
 Mappings::insert_hir_impl_block (HIR::ImplBlock *item)
 {
   auto id = item->get_mappings ().get_hirid ();
-  rust_assert (lookup_hir_impl_block (id) == nullptr);
+  rust_assert (!lookup_hir_impl_block (id));
 
   HirId impl_type_id = item->get_type ()->get_mappings ().get_hirid ();
   hirImplBlockMappings[id] = item;
@@ -476,12 +476,12 @@ Mappings::insert_hir_impl_block (HIR::ImplBlock *item)
   insert_node_to_hir (item->get_mappings ().get_nodeid (), id);
 }
 
-HIR::ImplBlock *
+tl::optional<HIR::ImplBlock *>
 Mappings::lookup_hir_impl_block (HirId id)
 {
   auto it = hirImplBlockMappings.find (id);
   if (it == hirImplBlockMappings.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 ef4d65639a0..109693e9c74 100644
--- a/gcc/rust/util/rust-hir-map.h
+++ b/gcc/rust/util/rust-hir-map.h
@@ -130,7 +130,7 @@ public:
   HIR::ExternalItem *lookup_hir_extern_item (HirId id, HirId *parent_block);
 
   void insert_hir_impl_block (HIR::ImplBlock *item);
-  HIR::ImplBlock *lookup_hir_impl_block (HirId id);
+  tl::optional<HIR::ImplBlock *> lookup_hir_impl_block (HirId id);
   bool lookup_impl_block_type (HirId id, HIR::ImplBlock **impl_block);
 
   void insert_module (HIR::Module *module);
-- 
2.45.2