Add a simulate_enum_decl langhook

Similarly to the simulate_builtin_function_decl patch, this one
adds a hook for simulating an enum declaration in the source
language.  Again, the main SVE ACLE patch has tests for various
error conditions.

2019-10-29  Richard Sandiford  <richard.sandiford@arm.com>

gcc/
	* coretypes.h (string_int_pair): New typedef.
	* langhooks-def.h (LANG_HOOKS_SIMULATE_ENUM_DECL): Define.
	(LANG_HOOKS_FOR_TYPES_INITIALIZER): Include it.
	* langhooks.h (lang_hooks_for_types::simulate_enum_decl): New hook.

gcc/c/
	* c-tree.h (c_simulate_enum_decl): Declare.
	* c-decl.c (c_simulate_enum_decl): New function.
	* c-objc-common.h (LANG_HOOKS_SIMULATE_ENUM_DECL): Define to the above.

gcc/cp/
	* cp-objcp-common.h (cxx_simulate_enum_decl): Declare.
	(LANG_HOOKS_SIMULATE_ENUM_DECL): Define to the above.
	* decl.c (cxx_simulate_enum_decl): New function.

From-SVN: r277555

3 files changed, 44 insertions, 0 deletions

diff --git a/gcc/cp/ChangeLog b/gcc/cp/ChangeLog
index 02cb6f3..c244438 100644
--- a/gcc/cp/ChangeLog
+++ b/gcc/cp/ChangeLog
@@ -1,5 +1,11 @@
 2019-10-29  Richard Sandiford  <richard.sandiford@arm.com>
 
+	* cp-objcp-common.h (cxx_simulate_enum_decl): Declare.
+	(LANG_HOOKS_SIMULATE_ENUM_DECL): Define to the above.
+	* decl.c (cxx_simulate_enum_decl): New function.
+
+2019-10-29  Richard Sandiford  <richard.sandiford@arm.com>
+
 	* cp-tree.h (cxx_simulate_builtin_function_decl): Declare.
 	* decl.c (cxx_simulate_builtin_function_decl): New function.
 	* cp-objcp-common.h (LANG_HOOKS_SIMULATE_BUILTIN_FUNCTION_DECL): Define
diff --git a/gcc/cp/cp-objcp-common.h b/gcc/cp/cp-objcp-common.h
index 1827e53..e5d34f1 100644
--- a/gcc/cp/cp-objcp-common.h
+++ b/gcc/cp/cp-objcp-common.h
@@ -35,6 +35,8 @@ extern tree cp_get_global_decls ();
 extern tree cp_pushdecl (tree);
 extern void cp_register_dumps (gcc::dump_manager *);
 extern tree cxx_make_type_hook			(tree_code);
+extern tree cxx_simulate_enum_decl (location_t, const char *,
+				    vec<string_int_pair>);
 
 /* Lang hooks that are shared between C++ and ObjC++ are defined here.  Hooks
    specific to C++ or ObjC++ go in cp/cp-lang.c and objcp/objcp-lang.c,
@@ -131,6 +133,8 @@ extern tree cxx_make_type_hook			(tree_code);
 
 #undef LANG_HOOKS_MAKE_TYPE
 #define LANG_HOOKS_MAKE_TYPE cxx_make_type_hook
+#undef LANG_HOOKS_SIMULATE_ENUM_DECL
+#define LANG_HOOKS_SIMULATE_ENUM_DECL cxx_simulate_enum_decl
 #undef LANG_HOOKS_TYPE_FOR_MODE
 #define LANG_HOOKS_TYPE_FOR_MODE c_common_type_for_mode
 #undef LANG_HOOKS_TYPE_FOR_SIZE
diff --git a/gcc/cp/decl.c b/gcc/cp/decl.c
index dccde80..95c8415 100644
--- a/gcc/cp/decl.c
+++ b/gcc/cp/decl.c
@@ -15433,6 +15433,40 @@ lookup_enumerator (tree enumtype, tree name)
   return e? TREE_VALUE (e) : NULL_TREE;
 }
 
+/* Implement LANG_HOOKS_SIMULATE_ENUM_DECL.  */
+
+tree
+cxx_simulate_enum_decl (location_t loc, const char *name,
+			vec<string_int_pair> values)
+{
+  location_t saved_loc = input_location;
+  input_location = loc;
+
+  tree enumtype = start_enum (get_identifier (name), NULL_TREE, NULL_TREE,
+			      NULL_TREE, false, NULL);
+  if (!OPAQUE_ENUM_P (enumtype))
+    {
+      error_at (loc, "multiple definition of %q#T", enumtype);
+      inform (DECL_SOURCE_LOCATION (TYPE_MAIN_DECL (enumtype)),
+	      "previous definition here");
+      return enumtype;
+    }
+  SET_OPAQUE_ENUM_P (enumtype, false);
+  DECL_SOURCE_LOCATION (TYPE_NAME (enumtype)) = loc;
+
+  string_int_pair *value;
+  unsigned int i;
+  FOR_EACH_VEC_ELT (values, i, value)
+    build_enumerator (get_identifier (value->first),
+		      build_int_cst (integer_type_node, value->second),
+		      enumtype, NULL_TREE, loc);
+
+  finish_enum_value_list (enumtype);
+  finish_enum (enumtype);
+
+  input_location = saved_loc;
+  return enumtype;
+}
 
 /* We're defining DECL.  Make sure that its type is OK.  */