1 files changed, 69 insertions, 0 deletions
diff --git a/scripts/gcc-plugins/cyc_complexity_plugin.c b/scripts/gcc-plugins/cyc_complexity_plugin.c
new file mode 100644
index 000000000..73124c2b3
--- /dev/null
+++ b/scripts/gcc-plugins/cyc_complexity_plugin.c
@@ -0,0 +1,69 @@
+/*
+ * Copyright 2011-2016 by Emese Revfy <re.emese@gmail.com>
+ * Licensed under the GPL v2, or (at your option) v3
+ *
+ * Homepage:
+ * https://github.com/ephox-gcc-plugins/cyclomatic_complexity
+ *
+ * https://en.wikipedia.org/wiki/Cyclomatic_complexity
+ * The complexity M is then defined as:
+ * M = E - N + 2P
+ * where
+ *
+ *  E = the number of edges of the graph
+ *  N = the number of nodes of the graph
+ *  P = the number of connected components (exit nodes).
+ *
+ * Usage (4.5 - 5):
+ * $ make clean; make run
+ */
+
+#include "gcc-common.h"
+
+__visible int plugin_is_GPL_compatible;
+
+static struct plugin_info cyc_complexity_plugin_info = {
+	.version	= "20160225",
+	.help		= "Cyclomatic Complexity\n",
+};
+
+static unsigned int cyc_complexity_execute(void)
+{
+	int complexity;
+	expanded_location xloc;
+
+	/* M = E - N + 2P */
+	complexity = n_edges_for_fn(cfun) - n_basic_blocks_for_fn(cfun) + 2;
+
+	xloc = expand_location(DECL_SOURCE_LOCATION(current_function_decl));
+	fprintf(stderr, "Cyclomatic Complexity %d %s:%s\n", complexity,
+		xloc.file, DECL_NAME_POINTER(current_function_decl));
+
+	return 0;
+}
+
+#define PASS_NAME cyc_complexity
+
+#define NO_GATE
+#define TODO_FLAGS_FINISH TODO_dump_func
+
+#include "gcc-generate-gimple-pass.h"
+
+__visible int plugin_init(struct plugin_name_args *plugin_info, struct plugin_gcc_version *version)
+{
+	const char * const plugin_name = plugin_info->base_name;
+
+	PASS_INFO(cyc_complexity, "ssa", 1, PASS_POS_INSERT_AFTER);
+
+	if (!plugin_default_version_check(version, &gcc_version)) {
+		error(G_("incompatible gcc/plugin versions"));
+		return 1;
+	}
+
+	register_callback(plugin_name, PLUGIN_INFO, NULL,
+				&cyc_complexity_plugin_info);
+	register_callback(plugin_name, PLUGIN_PASS_MANAGER_SETUP, NULL,
+				&cyc_complexity_pass_info);
+
+	return 0;
+}