1 /*
2  * Copyright 2011-2016 by Emese Revfy <re.emese@gmail.com>
3  * Licensed under the GPL v2, or (at your option) v3
4  *
5  * Homepage:
6  * https://github.com/ephox-gcc-plugins/cyclomatic_complexity
7  *
8  * http://en.wikipedia.org/wiki/Cyclomatic_complexity
9  * The complexity M is then defined as:
10  * M = E - N + 2P
11  * where
12  *
13  *  E = the number of edges of the graph
14  *  N = the number of nodes of the graph
15  *  P = the number of connected components (exit nodes).
16  *
17  * Usage (4.5 - 5):
18  * $ make clean; make run
19  */
20 
21 #include "gcc-common.h"
22 
23 __visible int plugin_is_GPL_compatible;
24 
25 static struct plugin_info cyc_complexity_plugin_info = {
26 	.version	= "20160225",
27 	.help		= "Cyclomatic Complexity\n",
28 };
29 
cyc_complexity_execute(void)30 static unsigned int cyc_complexity_execute(void)
31 {
32 	int complexity;
33 	expanded_location xloc;
34 
35 	/* M = E - N + 2P */
36 	complexity = n_edges_for_fn(cfun) - n_basic_blocks_for_fn(cfun) + 2;
37 
38 	xloc = expand_location(DECL_SOURCE_LOCATION(current_function_decl));
39 	fprintf(stderr, "Cyclomatic Complexity %d %s:%s\n", complexity,
40 		xloc.file, DECL_NAME_POINTER(current_function_decl));
41 
42 	return 0;
43 }
44 
45 #define PASS_NAME cyc_complexity
46 
47 #define NO_GATE
48 #define TODO_FLAGS_FINISH TODO_dump_func
49 
50 #include "gcc-generate-gimple-pass.h"
51 
plugin_init(struct plugin_name_args * plugin_info,struct plugin_gcc_version * version)52 __visible int plugin_init(struct plugin_name_args *plugin_info, struct plugin_gcc_version *version)
53 {
54 	const char * const plugin_name = plugin_info->base_name;
55 
56 	PASS_INFO(cyc_complexity, "ssa", 1, PASS_POS_INSERT_AFTER);
57 
58 	if (!plugin_default_version_check(version, &gcc_version)) {
59 		error(G_("incompatible gcc/plugin versions"));
60 		return 1;
61 	}
62 
63 	register_callback(plugin_name, PLUGIN_INFO, NULL,
64 				&cyc_complexity_plugin_info);
65 	register_callback(plugin_name, PLUGIN_PASS_MANAGER_SETUP, NULL,
66 				&cyc_complexity_pass_info);
67 
68 	return 0;
69 }
70