linux-imx

/*

 * 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/sancov

 *

 * This plugin inserts a __sanitizer_cov_trace_pc() call at the start of basic blocks.

 * It supports all gcc versions with plugin support (from gcc-4.5 on).

 * It is based on the commit "Add fuzzing coverage support" by Dmitry Vyukov <dvyukov@google.com>.

 *

 * You can read about it more here:

 *  https://gcc.gnu.org/viewcvs/gcc?limit_changes=0&view=revision&revision=231296

 *  http://lwn.net/Articles/674854/

 *  https://github.com/google/syzkaller

 *  https://lwn.net/Articles/677764/

 *

 * Usage:

 * make run

 */

​

#include "gcc-common.h"

​

__visible int plugin_is_GPL_compatible;

​

tree sancov_fndecl;

​

static struct plugin_info sancov_plugin_info = {

    .version    = "20160402",

    .help       = "sancov plugin\n",

};

​

static unsigned int sancov_execute(void)

{

    basic_block bb;

​

    /* Remove this line when this plugin and kcov will be in the kernel.

    if (!strcmp(DECL_NAME_POINTER(current_function_decl), DECL_NAME_POINTER(sancov_fndecl)))

        return 0;

    */

​

    FOR_EACH_BB_FN(bb, cfun) {

        const_gimple stmt;

        gcall *gcall;

        gimple_stmt_iterator gsi = gsi_after_labels(bb);

​

        if (gsi_end_p(gsi))

            continue;

​

        stmt = gsi_stmt(gsi);

        gcall = as_a_gcall(gimple_build_call(sancov_fndecl, 0));

        gimple_set_location(gcall, gimple_location(stmt));

        gsi_insert_before(&gsi, gcall, GSI_SAME_STMT);

    }

    return 0;

}

​

#define PASS_NAME sancov

​

#define NO_GATE

#define TODO_FLAGS_FINISH TODO_dump_func | TODO_verify_stmts | TODO_update_ssa_no_phi | TODO_verify_flow

​

#include "gcc-generate-gimple-pass.h"

​

static void sancov_start_unit(void __unused *gcc_data, void __unused *user_data)

{

    tree leaf_attr, nothrow_attr;

    tree BT_FN_VOID = build_function_type_list(void_type_node, NULL_TREE);

​

    sancov_fndecl = build_fn_decl("__sanitizer_cov_trace_pc", BT_FN_VOID);

​

    DECL_ASSEMBLER_NAME(sancov_fndecl);

    TREE_PUBLIC(sancov_fndecl) = 1;

    DECL_EXTERNAL(sancov_fndecl) = 1;

    DECL_ARTIFICIAL(sancov_fndecl) = 1;

    DECL_PRESERVE_P(sancov_fndecl) = 1;

    DECL_UNINLINABLE(sancov_fndecl) = 1;

    TREE_USED(sancov_fndecl) = 1;

​

    nothrow_attr = tree_cons(get_identifier("nothrow"), NULL, NULL);

    decl_attributes(&sancov_fndecl, nothrow_attr, 0);

    gcc_assert(TREE_NOTHROW(sancov_fndecl));

#if BUILDING_GCC_VERSION > 4005

    leaf_attr = tree_cons(get_identifier("leaf"), NULL, NULL);

    decl_attributes(&sancov_fndecl, leaf_attr, 0);

#endif

}

​

__visible int plugin_init(struct plugin_name_args *plugin_info, struct plugin_gcc_version *version)

{

    int i;

    const char * const plugin_name = plugin_info->base_name;