Add domain_search_flags

This adds a new flag enum type, domain_search_flags, which is the flag
version of domain_enum.  Nothing uses this yet, but the goal here is
to have all symbol searches and lookups use these flags.  The new
names are chosen to exactly parallel domain_enum.

gdb/symtab.c

@@ -331,6 +331,21 @@ search_domain_name (enum search_domain e)
 
 /* See symtab.h.  */
 
+std::string
+domain_name (domain_search_flags flags)
+{
+  static constexpr domain_search_flags::string_mapping mapping[] = {
+#define DOMAIN(X) \
+    MAP_ENUM_FLAG (SEARCH_ ## X ## _DOMAIN),
+#include "sym-domains.def"
+#undef DOMAIN
+  };
+
+  return flags.to_string (mapping);
+}
+
+/* See symtab.h.  */
+
 CORE_ADDR
 linetable_entry::pc (const struct objfile *objfile) const
 {
@@ -2666,6 +2681,41 @@ symbol_matches_domain (enum language symbol_language,
 
 /* See symtab.h.  */
 
+bool
+symbol::matches (domain_search_flags flags) const
+{
+  if (language () != language_c
+      && language () != language_objc
+      && language () != language_opencl)
+    {
+      /* Only C languages distinguish tag and type namespaces.  */
+      if ((flags & SEARCH_TYPE_DOMAIN) != 0)
+	flags |= SEARCH_STRUCT_DOMAIN;
+    }
+
+  if ((flags & SEARCH_FUNCTION_DOMAIN) != 0
+      && domain () == VAR_DOMAIN
+      && aclass () == LOC_BLOCK)
+    return true;
+
+  if ((flags & SEARCH_VAR_DOMAIN) != 0
+      && domain () == VAR_DOMAIN)
+    return true;
+
+  if ((flags & SEARCH_TYPE_DOMAIN) != 0
+      && domain () == VAR_DOMAIN
+      && aclass () == LOC_TYPEDEF)
+    return true;
+
+  if ((flags & SEARCH_STRUCT_DOMAIN) != 0
+      && domain () == STRUCT_DOMAIN)
+    return true;
+
+  return search_flags_matches (flags, m_domain);
+}
+
+/* See symtab.h.  */
+
 struct type *
 lookup_transparent_type (const char *name)
 {

gdb/symtab.h

@@ -905,6 +905,48 @@ enum domain_enum
 
 extern const char *domain_name (domain_enum);
 
+/* Flags used for searching symbol tables.  These can be combined to
+   let the search match multiple kinds of symbol.  */
+enum domain_search_flag
+{
+#define DOMAIN(X) \
+  SEARCH_ ## X ## _DOMAIN = (1 << X ## _DOMAIN),
+#include "sym-domains.def"
+#undef DOMAIN
+};
+DEF_ENUM_FLAGS_TYPE (enum domain_search_flag, domain_search_flags);
+
+/* A convenience constant to search for any symbol.  */
+constexpr domain_search_flags SEARCH_ALL
+    = ((domain_search_flags) 0
+#define DOMAIN(X) | SEARCH_ ## X ## _DOMAIN
+#include "sym-domains.def"
+#undef DOMAIN
+       );
+
+/* A convenience define for "C-like" name lookups, matching variables,
+   types, and functions.  */
+#define SEARCH_VFT \
+  (SEARCH_VAR_DOMAIN | SEARCH_FUNCTION_DOMAIN | SEARCH_TYPE_DOMAIN)
+
+/* Return a string representing the given flags.  */
+extern std::string domain_name (domain_search_flags);
+
+/* Convert a symbol domain to search flags.  */
+static inline domain_search_flags 
+to_search_flags (domain_enum domain)
+{
+  return domain_search_flags (domain_search_flag (1 << domain));
+}
+
+/* Return true if the given domain matches the given flags, false
+   otherwise.  */
+static inline bool
+search_flags_matches (domain_search_flags flags, domain_enum domain)
+{
+  return (flags & to_search_flags (domain)) != 0;
+}
+
 /* Searching domains, used when searching for symbols.  Element numbers are
    hardcoded in GDB, check all enum uses before changing it.  */
 
@@ -1265,6 +1307,9 @@ struct symbol : public general_symbol_info, public allocate_on_obstack
     return symbol_matches_domain (language (), domain (), d);
   }
 
+  /* Return true if this symbol's domain matches FLAGS.  */
+  bool matches (domain_search_flags flags) const;
+
   domain_enum domain () const
   {
     return m_domain;