# Copyright (C) 2018-2021 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 file is part of the gdb testsuite.

# Test access to special purpose register TAR (the Target Address
# Register).  The test inferior writes to this register, we check that
# GDB reads the same value, then write to the register the address of
# another label.  We then let the inferior continue and execute a
# branch to TAR and check that we stop at the address that we wrote to
# register.

if {![istarget "powerpc*-*-linux*"]} then {
    verbose "Skipping PowerPC test for the TAR register."
    return
}

standard_testfile .c

if {[build_executable "compile" $binfile $srcfile {debug}] == -1} {
    return -1
}

proc check_register_access { regname } {
    global gdb_prompt

    set test "$regname register access"
    gdb_test_multiple "info reg $regname" "$test" {
	-re "Invalid register.*\r\n$gdb_prompt $" {
	    unsupported "$test"
	    return 0
	}
	-re "\r\n$regname.*\r\n$gdb_prompt $" {
	    pass "$test"
	    return 1
	}
    }
    return 0
}

proc tar_available {} {
    global gdb_prompt
    global inferior_exited_re

    set test "TAR available to inferior"
    gdb_test_multiple "continue" "" {
	-re "Illegal instruction.*\r\n$gdb_prompt $" {
	    unsupported "$test"
	    return 0
	}
	-re "$inferior_exited_re normally.*$gdb_prompt $" {
	    pass "$test"
	    return 1
	}
    }
    return 0
}

# Do one pass to check if TAR is usable, system
# software can prevent it from being used.
with_test_prefix "check TAR access" {
    clean_restart $binfile

    if ![runto_main] {
	return
    }

    if {![check_register_access "tar"]} {
	return
    }

    if {![tar_available]} {
	return
    }
}

# Now do the actual test
clean_restart $binfile

if ![runto_main] {
    return
}

gdb_breakpoint [gdb_get_line_number "marker"]

gdb_continue_to_breakpoint "continue to marker"

set target1 [get_hexadecimal_valueof "target1" -1]
set tar [get_hexadecimal_valueof "\$tar" -2]

set test "TAR value from mtspr"

if {${target1} == ${tar}} {
    pass $test
} else {
    fail $test
}

set target2 [get_hexadecimal_valueof "target2" -1]

if {$target2 == -1} {
    fail "Could not get value of target2"
    return
}

gdb_test_no_output "set \$tar = $target2" "set tar"

gdb_breakpoint [gdb_get_line_number "marker 2"]

gdb_continue_to_breakpoint "continue to new target address" ".*marker 2.*"