Add rib kind debug representation

Rib kind had no string representation, and thus were not used in the
debug string representation.

gcc/rust/ChangeLog:

	* resolve/rust-forever-stack.hxx: Output rib kind.
	* resolve/rust-rib.h: Add function to get string representation from
	a rib kind.

Signed-off-by: Pierre-Emmanuel Patry <[email protected]>

Author: P-E-P

gcc/rust/resolve/rust-forever-stack.hxx

@@ -781,13 +781,17 @@ ForeverStack<N>::stream_rib (std::stringstream &stream, const Rib &rib,
 			     const std::string &next,
 			     const std::string &next_next) const
 {
+  std::string rib_kind = Rib::kind_to_string (rib.kind);
+  stream << next << "rib [" << rib_kind << "]: {";
   if (rib.get_values ().empty ())
     {
-      stream << next << "rib: {},\n";
+      stream << "}\n";
       return;
     }
-
-  stream << next << "rib: {\n";
+  else
+    {
+      stream << "\n";
+    }
 
   for (const auto &kv : rib.get_values ())
     stream << next_next << kv.first << ": " << kv.second.to_string () << "\n";

gcc/rust/resolve/rust-rib.h

@@ -175,6 +175,35 @@ class Rib
     ConstParamType,
   } kind;
 
+  static std::string kind_to_string (Rib::Kind kind)
+  {
+    switch (kind)
+      {
+      case Rib::Kind::Normal:
+	return "Normal";
+      case Rib::Kind::Module:
+	return "Module";
+      case Rib::Kind::Function:
+	return "Function";
+      case Rib::Kind::ConstantItem:
+	return "ConstantItem";
+      case Rib::Kind::TraitOrImpl:
+	return "TraitOrImpl";
+      case Rib::Kind::Item:
+	return "Item";
+      case Rib::Kind::Closure:
+	return "Closure";
+      case Rib::Kind::MacroDefinition:
+	return "Macro definition";
+      case Rib::Kind::ForwardTypeParamBan:
+	return "Forward type param ban";
+      case Rib::Kind::ConstParamType:
+	return "Const Param Type";
+      default:
+	rust_unreachable ();
+      }
+  }
+
   Rib (Kind kind);
   Rib (Kind kind, std::string identifier, NodeId id);
   Rib (Kind kind, std::unordered_map<std::string, NodeId> values);