# Copyright (C) 2017-2018 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/>.


if { ![istarget i?86-*-*] && ![istarget x86_64-*-* ] } {
    untested "skipping x86 MPX tests."
    return
}

standard_testfile

set comp_flags "-mmpx -fcheck-pointer-bounds -I${srcdir}/../nat"

if {[prepare_for_testing "failed to prepare" ${testfile} ${srcfile} \
    [list debug additional_flags=${comp_flags}]] } {
    return -1
}

if ![runto_main] {
    untested "could not run to main"
    return -1
}

set test "check whether processor supports MPX"
gdb_test_multiple "print have_mpx ()" $test {
    -re ".*= 1\r\n$gdb_prompt " {
        pass $test
    }
    -re ".*= 0\r\n$gdb_prompt " {
        pass $test
        untested "processor does not support MPX; skipping tests"
        return
    }
}

# Convenience for returning from an inferior call that causes a BND violation.
#
gdb_test_no_output "set confirm off"

# Convenience variable.
#
set bound_reg " = \\\{lbound = $hex, ubound = $hex\\\}.*"
set int_braw_reg " = \\\{lbound = 0x0, ubound_raw = 0x0\\\}.*"
set bndcfg_reg " = \\\{raw = $hex, config = \\\{base = $hex, reserved = $hex,\
               preserved = $hex, enabled = $hex\\\}\\\}"
set bndstatus_reg  " = \\\{raw = $hex, status = \\\{bde = $hex,\
                    error = $hex\\\}\\\}"
set u_fault [multi_line "Program received signal SIGSEGV, Segmentation fault" \
                        "Upper bound violation while accessing address $hex" \
                        "Bounds: \\\[lower = $hex, upper = $hex\\\]"]


# Simplify the tests below.
#
proc sanity_check_bndregs {arglist} {

    global int_braw_reg

    foreach a $arglist {
        gdb_test "p /x $a" "$int_braw_reg"\
            "$a"
    }
}

# Set bnd register to have no access to memory.
#
proc remove_memory_access {reg} {
    global hex

    sanity_check_bndregs {"\$bnd0raw" "\$bnd1raw" "\$bnd2raw" "\$bnd3raw"}

    gdb_test "p /x $reg.lbound = $reg.ubound" "= $hex"\
        "$reg lower bound set"
    gdb_test "p /x $reg.ubound = 0" " = 0x0"\
        "$reg upper bound set"
}


# Prepare convenience variables for bndconfig and status
# for posterior comparison.
#
proc prepare_bndcfg_bndstatus {} {

    global bndcfg_reg
    global bndstatus_reg

    gdb_test "p /x \$temp_bndcfgu = \$bndcfgu" "$bndcfg_reg"\
        "bndcfgu should not change"

    gdb_test "p /x \$temp_bndstatus = \$bndstatus" "$bndstatus_reg"\
        "bndstatus should not change"
}

# Compare values set for convenience variables and actual values of bndconfig
# and bndstatus registers.
#
proc compare_bndstatus_with_convenience {} {

    gdb_test "p \$temp_bndcfgu == \$bndcfgu" "= 1"\
        "bndcfgu compare before and after"
    gdb_test "p \$temp_bndstatus == \$bndstatus" "= 1"\
        "bndstatus compare before and after"
}

# Perform an inferior call defined in func.
#
proc perform_a_call {func} {

    global inf_call_stopped
    global gdb_prompt

    gdb_test "p /x $func" [multi_line "The program being debugged\
                          stopped while in a function called from GDB." \
                          "Evaluation of the expression containing the\
                          function.*" \
                          ] "inferior call stopped"
}

# Perform an inferior call defined in func.
#
proc check_bound_violation {parm parm_type is_positive} {

    global u_fault

    gdb_test "continue" "$u_fault.*" "continue to a bnd violation"

    set message "access only one position"
    if {$is_positive == 1} {
        gdb_test "p (((void *)\$_siginfo._sifields._sigfault.si_addr\
                  - (void*)$parm))/sizeof($parm_type) == 1"\
                  " = 1" $message
    } else {
        gdb_test "p ((void*)$parm\
                  - (void *)\$_siginfo._sifields._sigfault.si_addr)\
                  /sizeof($parm_type) == 1"\
                  " = 1" $message
    }
    gdb_test "return" "\\\#.*main.*i386-mpx-call\\\.c:.*" "return from the fault"
}


# Start testing!
#

# Set up for stopping in the middle of main for calling a function in the
# inferior.
#
set break "bkpt 1."
gdb_breakpoint [gdb_get_line_number "${break}"]
gdb_continue_to_breakpoint "${break}" ".*${break}.*"


# Consistency:
#    default run execution of call should succeed without violations.
#
with_test_prefix "default_run" {

    gdb_test "p \$keep_bnd0_value=\$bnd0" $bound_reg\
        "store bnd0 register in a convenience variable"

    gdb_test "p /x upper (a, b, c, d, 0)" " = $hex"\
        "default inferior call"

    gdb_test "p ((\$bnd0.lbound==\$keep_bnd0_value.lbound) &&\
        (\$bnd0.ubound==\$keep_bnd0_value.ubound))" "= 1" \
        "bnd register value after and before call"
}

# Consistency:  Examine bnd registers values before and after the call.
#
#
with_test_prefix "verify_default_values" {

    prepare_bndcfg_bndstatus

    gdb_breakpoint "*upper"
    perform_a_call "upper (a, b, c, d, 1)"

    sanity_check_bndregs {"\$bnd0raw" "\$bnd1raw" "\$bnd2raw" "\$bnd3raw"}

    compare_bndstatus_with_convenience

    gdb_test_multiple "continue" "inferior call test" {
        -re ".*Continuing.\r\n$gdb_prompt " {
            pass "inferior call performed"
        }
    }
}

# Examine:  Cause an upper bound violation changing BND0.
#
#
with_test_prefix "upper_bnd0" {

    prepare_bndcfg_bndstatus

    gdb_breakpoint "*upper"
    perform_a_call "upper (a, b, c, d, 1)"

    remove_memory_access "\$bnd0"

    compare_bndstatus_with_convenience

    check_bound_violation "a" "int" 1
}

# Examine:  Cause an upper bound violation changing BND1.
#
#
with_test_prefix "upper_bnd1" {

    prepare_bndcfg_bndstatus

    gdb_breakpoint "*upper"
    perform_a_call "upper (a, b, c, d, 1)"

    remove_memory_access "\$bnd1"

    compare_bndstatus_with_convenience

    check_bound_violation "b" "int" 1
}

# Examine:  Cause an upper bound violation changing BND2.
#
#
with_test_prefix "upper_bnd2" {

    prepare_bndcfg_bndstatus

    gdb_breakpoint "*upper"
    perform_a_call "upper (a, b, c, d, 1)"

    remove_memory_access "\$bnd2"

    compare_bndstatus_with_convenience

    check_bound_violation "c" "int" 1
}

# Examine:  Cause an upper bound violation changing BND3.
#
#
with_test_prefix "upper_bnd3" {
    prepare_bndcfg_bndstatus

    gdb_breakpoint "*upper"
    perform_a_call "upper (a, b, c, d, 1)"

    remove_memory_access "\$bnd3"

    compare_bndstatus_with_convenience

    check_bound_violation "d" "int" 1
}

# Examine:  Cause a lower bound violation changing BND0.
#
#
with_test_prefix "lower_bnd0" {

    prepare_bndcfg_bndstatus

    gdb_breakpoint "*lower"
    perform_a_call "lower (a, b, c, d, 1)"

    remove_memory_access "\$bnd0"

    compare_bndstatus_with_convenience

    check_bound_violation "a" "int" 0
}

# Examine:  Cause a lower bound violation changing BND1.
#
#
with_test_prefix "lower_bnd1" {

    prepare_bndcfg_bndstatus

    gdb_breakpoint "*lower"
    perform_a_call "lower (a, b, c, d, 1)"

    remove_memory_access "\$bnd1"

    compare_bndstatus_with_convenience

    check_bound_violation "b" "int" 0
}

# Examine:  Cause a lower bound violation changing BND2.
#
#
with_test_prefix "lower_bnd2" {

    prepare_bndcfg_bndstatus

    gdb_breakpoint "*lower"
    perform_a_call "lower (a, b, c, d, 1)"

    remove_memory_access "\$bnd2"

    compare_bndstatus_with_convenience

    check_bound_violation "c" "int" 0
}

# Examine:  Cause a lower bound violation changing BND3.
#
#
with_test_prefix "lower_bnd3" {

    prepare_bndcfg_bndstatus

    gdb_breakpoint "*lower"
    perform_a_call "lower (a, b, c, d, 1)"

    remove_memory_access "\$bnd3"

    compare_bndstatus_with_convenience

    check_bound_violation "d" "int" 0
}

# Examine:  String causing a upper bound violation changing BND0.
#
#
with_test_prefix "chars_up" {

    prepare_bndcfg_bndstatus

    gdb_breakpoint "*char_upper"
    perform_a_call "char_upper (hello, 1)"

    remove_memory_access "\$bnd0"

    compare_bndstatus_with_convenience

    check_bound_violation "str" "char" 1
}


# Examine:  String causing an lower bound violation changing BND0.
#
#
with_test_prefix "chars_low" {

    prepare_bndcfg_bndstatus

    gdb_breakpoint "*char_lower"
    perform_a_call "char_lower (hello, 1)"

    remove_memory_access "\$bnd0"

    compare_bndstatus_with_convenience

    check_bound_violation "str" "char" 0
}

# Examine:  String causing an lower bound violation changing BND0.
#
#
with_test_prefix "chars_low_adhoc_parm" {

    prepare_bndcfg_bndstatus

    gdb_breakpoint "*char_lower"
    perform_a_call "char_lower (\"tryme\", 1)"

    remove_memory_access "\$bnd0"

    compare_bndstatus_with_convenience

    check_bound_violation "str" "char" 0
}