# Copyright (C) 2016-2020 Free Software Foundation, Inc.

# This program is free software; you can redistribute it and/or modify
# it under the terms of the GNU General Public License as published by
# the Free Software Foundation; either version 3 of the License, or
# (at your option) any later version.
#
# This program is distributed in the hope that it will be useful,
# but WITHOUT ANY WARRANTY; without even the implied warranty of
# MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
# GNU General Public License for more details.
#
# You should have received a copy of the GNU General Public License
# along with this program.  If not, see <http://www.gnu.org/licenses/>.

# This test case is to test the speed of GDB when it is single-stepping
# with skip directives active. There's no need to test skip directives that
# match functions we're stepping through. That's not the interesting case.
# The interesting case is where there are 100s or more classes or libraries,
# each providing their own set of skip directives.
#
# Parameters:
# SKIP_STEP_COUNT: the number of single steps GDB performs
# SKIP_DIRECTIVE_COUNT: the number of skip directives to create

load_lib perftest.exp

if [skip_perf_tests] {
    return 0
}

standard_testfile .cc skip-funcs.cc
set executable $testfile
set skip_func_file [standard_output_file $srcfile2]
set expfile $testfile.exp

# make check-perf RUNTESTFLAGS='skip-command.exp SKIP_STEP_COUNT=1000 ...'
if ![info exists SKIP_STEP_COUNT] {
    set SKIP_STEP_COUNT 1000
}
if ![info exists SKIP_DIRECTIVE_COUNT] {
    set SKIP_DIRECTIVE_COUNT 1000
}

proc delete_all_skips { } {
    # FIXME: skip currently doesn't ask for confirmation
    # FIXME: "skip delete" with no skips ->
    #   "No skiplist entries found with number (null)."
    gdb_test_no_output "set confirm off"
    gdb_test "skip delete" ""
    gdb_test_no_output "set confirm on"
}

proc install_skips { kind text nr_skips } {
    global gdb_prompt
    set test "install_skips"
    delete_all_skips
    switch $kind {
	"function" { set skip_arg "-function" }
	"regexp" { set skip_arg "-rfunction" }
	default {
	    perror "bad skip kind: $kind"
	    return
	}
    }
    for { set i 0 } { $i < $nr_skips } { incr i } {
	gdb_test "skip $skip_arg [format $text $i]" ""
    }
    # There could be 1000's of these, which can overflow the buffer.
    # However, it's good to have this in the log, so we go to the effort
    # to read it all in.
    gdb_test_multiple "info skip" $test {
	-re "\[^\r\n\]*\r\n" { exp_continue }
	-re "\[\r\n\]*$gdb_prompt $" {
	    pass $test
	}
	timeout {
	    fail "$test (timeout)"
	}
    }
}

proc write_skip_func_source { file_name func_name_prefix nr_funcs } {
    set f [open $file_name "w"]
    puts $f "// DO NOT EDIT, machine generated file.  See skip-command.exp."
    for { set i 0 } { $i < $nr_funcs } { incr i } {
	set func_name [format "${func_name_prefix}_%02d" $i]
	puts $f "int $func_name () { return 0; }"
    }
    close $f
}

proc run_skip_bench { kind text } {
    global SKIP_STEP_COUNT SKIP_DIRECTIVE_COUNT

    if ![runto_main] {
	fail "can't run to main"
	return -1
    }

    gdb_test_no_output "set variable flag = 1"

    for { set i 0 } { $i < 5 } { incr i } {
	set nr_skips [expr $i * $SKIP_DIRECTIVE_COUNT]
	install_skips $kind $text $nr_skips
	gdb_test_no_output "python SkipCommand\(\"skip-$kind-$nr_skips\", ${SKIP_STEP_COUNT}\).run()"
    }

    gdb_test "set variable flag = 0"
}

PerfTest::assemble {
    global srcdir subdir srcfile binfile skip_func_file
    global SKIP_DIRECTIVE_COUNT

    write_skip_func_source $skip_func_file "skip_func" [expr 4 * $SKIP_DIRECTIVE_COUNT]
    if { [gdb_compile [list "$srcdir/$subdir/$srcfile" $skip_func_file] ${binfile} executable {c++ debug}] != "" } {
	return -1
    }
    return 0
} {
    global binfile
    clean_restart $binfile
    return 0
} {
    global SKIP_STEP_COUNT SKIP_DIRECTIVE_COUNT

    with_test_prefix "time_skip_func" {
	# N.B. The function name must match the ones in skip-command.cc.
	run_skip_bench "function" "skip_func_%02d"
    }

    with_test_prefix "time_skip_constructor" {
	run_skip_bench "regexp" "^(skip_class_%02d)::\\1 *\\("
    }

    return 0
}