gdb/testsuite/gdb.arch/powerpc-ppr-dscr.exp

# 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 registers PPR and DSCR.  The test
# inferior writes to these registers, we check that GDB reads the same
# values, then write to the registers trough GDB, step once, and check
# again if we read back the same values.

if {![istarget "powerpc*-*-linux*"]} then {
    verbose "Skipping PowerPC test for PPR and DSCR registers."
    return
}

standard_testfile .c

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

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
}

# Do one pass to check if the instructions in our test programs are
# available to this processor (e.g. mtspr 3, RS for accessing DSCR).
proc ppr_dscr_available {} {
    global gdb_prompt
    global inferior_exited_re

    set test "PPR/DSCR 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
}

with_test_prefix "check PPR/DSCR access" {
    clean_restart $binfile

    if ![runto_main] {
	return
    }

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

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

    if {![ppr_dscr_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"

# At the breakpoint the inferior should have set the
# registers to these expected values.

with_test_prefix "before write" {
    gdb_test "info reg dscr" "dscr.*0x0*20\[ \t\]+.*"
    gdb_test "info reg ppr" "ppr.*0x0*8000000000000\[ \t\]+.*"
}

# Set Store Stream Enable in DSCR and set PPR to the medium-low
# priority.
gdb_test_no_output "set \$dscr = 0x8"
gdb_test_no_output "set \$ppr = 0xC000000000000"

gdb_test "stepi" "asm.*"

with_test_prefix "after write" {
    gdb_test "info reg dscr" "dscr.*0x0*8+\[ \t\]+.*"
    gdb_test "info reg ppr" "ppr.*0x0*\[cC\]000000000000\[ \t\]+.*"
}