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Elixir Cross Referencer

# This testcase is part of GDB, the GNU debugger.
#
# Copyright 2013-2020 Free Software Foundation, Inc.
#
# Contributed by Intel Corp. <markus.t.metzger@intel.com>
#
# 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/>.

if { [skip_btrace_tests] } {
    unsupported "target does not support record-btrace"
    return -1
}

standard_testfile
if {[gdb_compile_pthreads "$srcdir/$subdir/$srcfile" "$binfile" executable {debug}] != "" } {
    untested "failed to prepare"
    return -1
}
clean_restart $testfile

if ![runto_main] {
    untested "failed to run to main"
    return -1
}

# set up breakpoints
set bp_1 [gdb_get_line_number "bp.1" $srcfile]
set bp_2 [gdb_get_line_number "bp.2" $srcfile]
set bp_3 [gdb_get_line_number "bp.3" $srcfile]

proc gdb_cont_to_line { line } {
    gdb_breakpoint $line
    gdb_continue_to_breakpoint "cont to $line" ".*$line\r\n.*"
    delete_breakpoints
}

proc check_replay_insn { thread insn } {
    gdb_test "thread apply $thread info record" \
        "Replay in progress\.  At instruction $insn\."
}

proc check_not_replaying { thread } {
    global gdb_prompt

    set test "thread $thread not replaying"

    gdb_test_multiple "thread apply $thread info record" $test {
        -re "Replay in progress" {
            fail $test
        }
        -re "$gdb_prompt $" {
            pass $test
        }
    }
}

# trace the code between the two breakpoints
delete_breakpoints
gdb_cont_to_line $srcfile:$bp_1
# make sure GDB knows about the new thread
gdb_test "info threads" ".*"
gdb_test_no_output "record btrace"
gdb_cont_to_line $srcfile:$bp_2

proc test_navigate {} {
    with_test_prefix "navigate" {
        gdb_test "thread 1" ".*"
        with_test_prefix "thread 1" {
            gdb_test "record goto begin" ".*"

            check_replay_insn 1 1
            check_not_replaying 2
        }
        gdb_test "thread 2" ".*"
        with_test_prefix "thread 2" {
            gdb_test "record goto begin" ".*"

            check_replay_insn 1 1
            check_replay_insn 2 1
        }
    }
}

proc test_step {} {
    with_test_prefix "step" {
        gdb_test "thread 1" ".*"
        with_test_prefix "thread 1" {
            gdb_test "stepi" ".*"

            check_replay_insn 1 2
            check_replay_insn 2 1
        }
        gdb_test "thread 2" ".*"
        with_test_prefix "thread 2" {
            gdb_test "stepi" ".*"

            check_replay_insn 1 2
            check_replay_insn 2 2
        }
    }
}

proc test_cont {} {
    with_test_prefix "cont" {
        gdb_test "thread 1" ".*"
        with_test_prefix "thread 1" {
            gdb_test "continue" "No more reverse-execution history.*"

            check_not_replaying 1
            check_replay_insn 2 2
        }
        gdb_test "thread 2" ".*"
        with_test_prefix "thread 2" {
            gdb_test "continue" "No more reverse-execution history.*"

            check_not_replaying 1
            check_not_replaying 2
        }
    }
}

proc test_cont_all {} {
    with_test_prefix "cont-all" {
        gdb_test "continue" "No more reverse-execution history.*"

        # this works because we're lock-stepping threads that executed exactly
        # the same code starting from the same instruction.

        check_not_replaying 1
        check_not_replaying 2
    }
}

proc test_rstep {} {
    with_test_prefix "reverse-step" {
        gdb_test "thread apply all record goto 3"

        gdb_test "thread 1" ".*"
        with_test_prefix "thread 1" {
            gdb_test "reverse-stepi" ".*"

            check_replay_insn 1 2
            check_replay_insn 2 3
        }
        gdb_test "thread 2" ".*"
        with_test_prefix "thread 2" {
            gdb_test "reverse-stepi" ".*"

            check_replay_insn 1 2
            check_replay_insn 2 2
        }
    }
}

proc test_goto_end {} {
    with_test_prefix "goto-end" {
        gdb_test "thread apply all record goto end"

        check_not_replaying 1
        check_not_replaying 2
    }
}

foreach schedlock { "replay" "on" "step" } {
    with_test_prefix "schedlock-$schedlock" {
        gdb_test_no_output "set scheduler-locking $schedlock"

        test_navigate
        test_step
        if { $schedlock == "step" } {
            test_cont_all
        } else {
            test_cont
        }
        test_rstep
        test_goto_end
    }
}

# schedlock-off is difficult to test since we can't really say where the other
# thread will be when the resumed thread stops.

# navigate back into the history for thread 1 and continue thread 2
with_test_prefix "cont-to-end" {
    # this test only works for scheduler-locking replay
    gdb_test_no_output "set scheduler-locking replay"

    gdb_test "thread 1" ".*"
    with_test_prefix "thread 1" {
        gdb_test "record goto begin" ".*"

        check_replay_insn 1 1
    }
    gdb_test "thread 2" ".*"
    with_test_prefix "thread 2" {
        gdb_test "record goto end" ".*"

        check_not_replaying 2

        # if we reach the breakpoint, thread 2 terminated...
        gdb_cont_to_line $srcfile:$bp_3

        # and thread 1 stopped replaying
        check_not_replaying 1
    }
}