Change C front end to emit structured loop and switch tree nodes.

2020-08-12  Sandra Loosemore  <sandra@codesourcery.com>

	gcc/c
	* c-decl.c (c_break_label, c_cont_label): Delete, and replace
	with...
	(in_statement): New.
	(start_function): Adjust for above change.
	(c_push_function_context, c_pop_function_context): Likewise.
	* c-lang.h (struct language_function): Likewise.
	* c-objc-common.h (LANG_HOOKS_BLOCK_MAY_FALLTHRU): Define.
	* c-parser.c (objc_foreach_break_label, objc_foreach_continue_label):
	New.
	(c_parser_statement_after_labels): Adjust calls to c_finish_bc_stmt.
	(c_parser_switch_statement): Adjust break/switch context handling
	and calls to renamed functions.
	(c_parser_while_statement): Adjust break/switch context handling and
	build a WHILE_STMT.
	(c_parser_do_statement): Ditto, with DO_STMT respectively.
	(c_parser_for_statement): Ditto, with FOR_STMT respectively.
	(c_parser_omp_for_loop): Adjust break/switch context handling.
	* c-tree.h (c_break_label, c_cont_label): Delete.
	(IN_SWITCH_STMT, IN_ITERATION_STMT): Define.
	(IN_OMP_BLOCK, IN_OMP_FOR, IN_OBJC_FOREACH): Define.
	(in_statement, switch_statement_break_seen_p): Declare.
	(c_start_case, c_finish_case): Renamed to...
	(c_start_switch, c_finish_switch).
	(c_finish_bc_stmt): Adjust arguments.
	* c-typeck.c (build_function_call_vec): Don't try to print
	statements with %qE format.
	(struct c_switch):  Rename switch_expr field to switch_stmt.
	Add break_stmt_seen_p field.
	(c_start_case): Rename to c_start_switch.  Build a SWITCH_STMT
	instead of a SWITCH_EXPR.  Update for changes to struct c_switch.
	(do_case): Update for changes to struct c_switch.
	(c_finish_case): Rename to c_finish_switch.  Update for changes to
	struct c_switch and change of representation from SWITCH_EXPR to
	SWITCH_STMT.
	(c_finish_loop): Delete.
	(c_finish_bc_stmt): Update to reflect changes to break/continue
	state representation.  Build a BREAK_STMT or CONTINUE_STMT instead
	of a GOTO_EXPR except for objc foreach loops.

	gcc/objc
	* objc-act.c (objc_start_method_definition): Update to reflect
	changes to break/continue state bookkeeping in C front end.

	gcc/testsuite/
	* gcc.dg/gomp/block-7.c: Update expected error message wording.

1 files changed, 16 insertions, 5 deletions

diff --git a/gcc/c/c-tree.h b/gcc/c/c-tree.h
index 10938cf..7e51859 100644
--- a/gcc/c/c-tree.h
+++ b/gcc/c/c-tree.h
@@ -547,8 +547,19 @@ extern void gen_aux_info_record (tree, int, int, int);
 struct c_spot_bindings;
 class c_struct_parse_info;
 extern struct obstack parser_obstack;
-extern tree c_break_label;
-extern tree c_cont_label;
+/* Set to IN_ITERATION_STMT if parsing an iteration-statement,
+   to IN_OMP_BLOCK if parsing OpenMP structured block and
+   IN_OMP_FOR if parsing OpenMP loop.  If parsing a switch statement,
+   this is bitwise ORed with IN_SWITCH_STMT, unless parsing an
+   iteration-statement, OpenMP block or loop within that switch.  */
+#define IN_SWITCH_STMT		1
+#define IN_ITERATION_STMT	2
+#define IN_OMP_BLOCK		4
+#define IN_OMP_FOR		8
+#define IN_OBJC_FOREACH		16
+extern unsigned char in_statement;
+
+extern bool switch_statement_break_seen_p;
 
 extern bool global_bindings_p (void);
 extern tree pushdecl (tree);
@@ -714,8 +725,8 @@ extern void process_init_element (location_t, struct c_expr, bool,
 extern tree build_compound_literal (location_t, tree, tree, bool,
 				    unsigned int);
 extern void check_compound_literal_type (location_t, struct c_type_name *);
-extern tree c_start_case (location_t, location_t, tree, bool);
-extern void c_finish_case (tree, tree);
+extern tree c_start_switch (location_t, location_t, tree, bool);
+extern void c_finish_switch (tree, tree);
 extern tree build_asm_expr (location_t, tree, tree, tree, tree, tree, bool,
 			    bool);
 extern tree build_asm_stmt (bool, tree);
@@ -730,7 +741,7 @@ extern tree c_finish_stmt_expr (location_t, tree);
 extern tree c_process_expr_stmt (location_t, tree);
 extern tree c_finish_expr_stmt (location_t, tree);
 extern tree c_finish_return (location_t, tree, tree);
-extern tree c_finish_bc_stmt (location_t, tree *, bool);
+extern tree c_finish_bc_stmt (location_t, tree, bool);
 extern tree c_finish_goto_label (location_t, tree);
 extern tree c_finish_goto_ptr (location_t, tree);
 extern tree c_expr_to_decl (tree, bool *, bool *);