/* ******************************************************************************
 * Copyright (c) 2014-2023 Google, Inc.  All rights reserved.
 * Copyright (c) 2011 Massachusetts Institute of Technology  All rights reserved.
 * Copyright (c) 2008 VMware, Inc.  All rights reserved.
 * ******************************************************************************/

/*
 * Redistribution and use in source and binary forms, with or without
 * modification, are permitted provided that the following conditions are met:
 *
 * * Redistributions of source code must retain the above copyright notice,
 *   this list of conditions and the following disclaimer.
 *
 * * Redistributions in binary form must reproduce the above copyright notice,
 *   this list of conditions and the following disclaimer in the documentation
 *   and/or other materials provided with the distribution.
 *
 * * Neither the name of VMware, Inc. nor the names of its contributors may be
 *   used to endorse or promote products derived from this software without
 *   specific prior written permission.
 *
 * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS"
 * AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
 * ARE DISCLAIMED. IN NO EVENT SHALL VMWARE, INC. OR CONTRIBUTORS BE LIABLE
 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR
 * SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER
 * CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH
 * DAMAGE.
 */

/* Code Manipulation API Sample:
 * inscount.cpp
 *
 * Reports the dynamic count of the total number of instructions executed.
 * Illustrates how to perform performant clean calls.
 * Demonstrates effect of clean call optimization and auto-inlining with
 * different -opt_cleancall values.
 *
 * The runtime options for this client include:
 *   -only_from_app  Do not count instructions in shared libraries.
 * The options are handled using the droption extension.
 */

#include "dr_api.h"
#include "drmgr.h"
#include "droption.h"
#include <string.h>

namespace dynamorio {
namespace samples {
namespace {

using ::dynamorio::droption::droption_parser_t;
using ::dynamorio::droption::DROPTION_SCOPE_ALL;
using ::dynamorio::droption::DROPTION_SCOPE_CLIENT;
using ::dynamorio::droption::droption_t;

#ifdef WINDOWS
#    define DISPLAY_STRING(msg) dr_messagebox(msg)
#else
#    define DISPLAY_STRING(msg) dr_printf("%s\n", msg);
#endif

#define NULL_TERMINATE(buf) (buf)[(sizeof((buf)) / sizeof((buf)[0])) - 1] = '\0'

static droption_t<bool> only_from_app(
    DROPTION_SCOPE_CLIENT, "only_from_app", false,
    "Only count app, not lib, instructions",
    "Count only instructions in the application itself, ignoring instructions in "
    "shared libraries.");

/* Application module */
static app_pc exe_start;
/* we only have a global count */
static uint64 global_count;
/* A simple clean call that will be automatically inlined because it has only
 * one argument and contains no calls to other functions.
 */
static void
inscount(uint num_instrs)
{
    global_count += num_instrs;
}
static void
event_exit(void);
static dr_emit_flags_t
event_bb_analysis(void *drcontext, void *tag, instrlist_t *bb, bool for_trace,
                  bool translating, void **user_data);
static dr_emit_flags_t
event_app_instruction(void *drcontext, void *tag, instrlist_t *bb, instr_t *inst,
                      bool for_trace, bool translating, void *user_data);

static void
event_exit(void)
{
#ifdef SHOW_RESULTS
    char msg[512];
    int len;
    len = dr_snprintf(msg, sizeof(msg) / sizeof(msg[0]),
                      "Instrumentation results: %llu instructions executed\n",
                      global_count);
    DR_ASSERT(len > 0);
    NULL_TERMINATE(msg);
    DISPLAY_STRING(msg);
#endif /* SHOW_RESULTS */
    drmgr_exit();
}

static dr_emit_flags_t
event_bb_analysis(void *drcontext, void *tag, instrlist_t *bb, bool for_trace,
                  bool translating, void **user_data)
{
    instr_t *instr;
    uint num_instrs;

#ifdef VERBOSE
    dr_printf("in dynamorio_basic_block(tag=" PFX ")\n", tag);
#    ifdef VERBOSE_VERBOSE
    instrlist_disassemble(drcontext, tag, bb, STDOUT);
#    endif
#endif
    /* Only count in app BBs */
    if (only_from_app.get_value()) {
        module_data_t *mod = dr_lookup_module(dr_fragment_app_pc(tag));
        if (mod != NULL) {
            bool from_exe = (mod->start == exe_start);
            dr_free_module_data(mod);
            if (!from_exe) {
                *user_data = NULL;
                return DR_EMIT_DEFAULT;
            }
        }
    }

    /* Count instructions. If an emulation client is running with this client,
     * we want to count all the original native instructions and the emulated
     * instruction but NOT the introduced native instructions used for emulation.
     */
    bool is_emulation = false;
    for (instr = instrlist_first(bb), num_instrs = 0; instr != NULL;
         instr = instr_get_next(instr)) {
        if (drmgr_is_emulation_start(instr)) {
            /* Each emulated instruction is replaced by a series of native
             * instructions delimited by labels indicating when the emulation
             * sequence begins and ends. It is the responsibility of the
             * emulation client to place the start/stop labels correctly.
             */
            num_instrs++;
            is_emulation = true;
            /* Data about the emulated instruction can be extracted from the
             * start label using the accessor function:
             * drmgr_get_emulated_instr_data()
             */
            continue;
        }
        if (drmgr_is_emulation_end(instr)) {
            is_emulation = false;
            continue;
        }
        if (is_emulation)
            continue;
        if (!instr_is_app(instr))
            continue;
        num_instrs++;
    }
    *user_data = (void *)(ptr_uint_t)num_instrs;

#if defined(VERBOSE) && defined(VERBOSE_VERBOSE)
    dr_printf("Finished counting for dynamorio_basic_block(tag=" PFX ")\n", tag);
    instrlist_disassemble(drcontext, tag, bb, STDOUT);
#endif
    return DR_EMIT_DEFAULT;
}

static dr_emit_flags_t
event_app_instruction(void *drcontext, void *tag, instrlist_t *bb, instr_t *instr,
                      bool for_trace, bool translating, void *user_data)
{
    uint num_instrs;
    /* By default drmgr enables auto-predication, which predicates all instructions with
     * the predicate of the current instruction on ARM.
     * We disable it here because we want to unconditionally execute the following
     * instrumentation.
     */
    drmgr_disable_auto_predication(drcontext, bb);
    if (!drmgr_is_first_instr(drcontext, instr))
        return DR_EMIT_DEFAULT;
    /* Only insert calls for in-app BBs */
    if (user_data == NULL)
        return DR_EMIT_DEFAULT;
    /* Insert clean call */
    num_instrs = (uint)(ptr_uint_t)user_data;
    dr_insert_clean_call(drcontext, bb, instrlist_first_app(bb), (void *)inscount,
                         false /* save fpstate */, 1, OPND_CREATE_INT32(num_instrs));
    return DR_EMIT_DEFAULT;
}

} // namespace
} // namespace samples
} // namespace dynamorio

DR_EXPORT void
dr_client_main(client_id_t id, int argc, const char *argv[])
{
    dr_set_client_name("DynamoRIO Sample Client 'inscount'",
                       "http://dynamorio.org/issues");

    /* Options */
    if (!dynamorio::droption::droption_parser_t::parse_argv(
            dynamorio::droption::DROPTION_SCOPE_CLIENT, argc, argv, NULL, NULL))
        DR_ASSERT(false);
    drmgr_init();

    /* Get main module address */
    if (dynamorio::samples::only_from_app.get_value()) {
        module_data_t *exe = dr_get_main_module();
        if (exe != NULL)
            dynamorio::samples::exe_start = exe->start;
        dr_free_module_data(exe);
    }

    /* register events */
    drmgr_register_exit_event(dynamorio::samples::event_exit);
    drmgr_register_bb_instrumentation_event(dynamorio::samples::event_bb_analysis,
                                            dynamorio::samples::event_app_instruction,
                                            NULL);

    /* make it easy to tell, by looking at log file, which client executed */
    dr_log(NULL, DR_LOG_ALL, 1, "Client 'inscount' initializing\n");
#ifdef SHOW_RESULTS
    /* also give notification to stderr */
    if (dr_is_notify_on()) {
#    ifdef WINDOWS
        /* ask for best-effort printing to cmd window.  must be called at init. */
        dr_enable_console_printing();
#    endif
        dr_fprintf(STDERR, "Client inscount is running\n");
    }
#endif
}