testsuite/gdb.threads/watchthreads.exp

# This testcase is part of GDB, the GNU debugger.

# Copyright 2004-2020 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/>.

# Check that GDB can support multiple watchpoints across threads.


# This test verifies that a watchpoint is detected in the proper thread
# so the test is only meaningful on a system with hardware watchpoints.
if {[skip_hw_watchpoint_multi_tests]} {
    return 0
}

proc target_no_stopped_data { } {
    return [istarget s390*-*-*]
}

standard_testfile
if {[gdb_compile_pthreads "${srcdir}/${subdir}/${srcfile}" "${binfile}" executable debug] != "" } {
    return -1
}

gdb_exit
gdb_start
gdb_reinitialize_dir $srcdir/$subdir
gdb_load ${binfile}

gdb_test_no_output "set can-use-hw-watchpoints 1" ""

#
# Run to `main' where we begin our tests.
#

if ![runto_main] then {
    fail "can't run to main"
    return 0
}

set args_0 0
set args_1 0

# Watch values that will be modified by distinct threads.
gdb_test "watch args\[0\]" "Hardware watchpoint 2: args\\\[0\\\]"
gdb_test "watch args\[1\]" "Hardware watchpoint 3: args\\\[1\\\]"
set hwwp_2_enabled 1
set hwwp_3_enabled 1

set init_line [gdb_get_line_number "Init value"]
set inc_line [gdb_get_line_number "Loop increment"]
set main_loc "main \\\(\\\) at .*watchthreads.c:$init_line"
set thread0_loc "thread_function \\\(arg=0x0\\\) at .*watchthreads.c:$inc_line"
set thread1_loc "thread_function \\\(arg=0x1\\\) at .*watchthreads.c:$inc_line"

# Loop and continue to allow both watchpoints to be triggered.
for {set i 0} {$i < 30} {incr i} {
  set test_flag_0 0
  set test_flag_1 0
  set test_flag 0
  gdb_test_multiple "continue" "threaded watch loop" {
    -re "(.*Hardware watchpoint.*)$gdb_prompt $" {
	# At least one hardware watchpoint was hit.  Check if both were.
	set string $expect_out(1,string)

	if [regexp "Hardware watchpoint 2: args\\\[0\\\]\[^\r\]*\r\[^\r\]*\r\[^\r\]*Old value = $args_0\[^\r\]*\r\[^\r\]*New value = [expr $args_0+1]\r" $string] {
	    incr args_0
	    incr test_flag_0
	}
	if [regexp "Hardware watchpoint 3: args\\\[1\\\]\[^\r\]*\r\[^\r\]*\r\[^\r\]*Old value = $args_1\[^\r\]*\r\[^\r\]*New value = [expr $args_1+1]\r" $string] {
	    incr args_1
	    incr test_flag_1
	}

	set expected_loc "bogus location"
	if { $test_flag_0 == 1 && $test_flag_1 == 0 && $args_0 == 1 } {
	    set expected_loc $main_loc
	} elseif { $test_flag_0 == 0 && $test_flag_1 == 1 && $args_1 == 1 } {
	    set expected_loc $main_loc
	} elseif { $test_flag_0 == 1 && $test_flag_1 == 0 } {
	    set expected_loc $thread0_loc
	} elseif { $test_flag_0 == 0 && $test_flag_1 == 1 } {
	    set expected_loc $thread1_loc
	} elseif { $test_flag_0 + $test_flag_1 == 2 } {
	    # On S/390, or any other system which can not report the
	    # stopped data address, it is OK to report two watchpoints
	    # at once in this test.  Make sure the reported location
	    # corresponds to at least one of the watchpoints (and not,
	    # e.g., __nptl_create_event).  On other systems, we should
	    # report the two watchpoints serially.
	    if { [target_no_stopped_data] } {
		set expected_loc "($main_loc|$thread0_loc|$thread1_loc)"
	    }
	}

	if [ regexp "$expected_loc" $string ] {
	    set test_flag 1
	} else {
	    fail "threaded watch loop"
	}

	# If one of the watchpoints is disabled, we'd better not stop there.
	if { !$hwwp_2_enabled && $test_flag_0 } {
	    fail "disabled hw watchpoint 2 triggered"
	}
	if { !$hwwp_3_enabled && $test_flag_1 } {
	    fail "disabled hw watchpoint 3 triggered"
	}

	# If we get to 10 in one of the watched locations disable it so we
	# see some of the other watched location.
	# 10 is chosen so we're guaranteed to come through here.
	if { $hwwp_2_enabled && $hwwp_3_enabled } {
	    if { $args_0 >= 10 && $hwwp_2_enabled } {
		gdb_test_no_output "disable 2" "disable first watchpoint at 10"
		set hwwp_2_enabled 0
	    } elseif { $args_1 >= 10 && $hwwp_3_enabled } {
		gdb_test_no_output "disable 3" "disable first watchpoint at 10"
		set hwwp_3_enabled 0
	    }
	}
    }
  }

  # If we fail above, don't bother continuing loop
  if { $test_flag == 0 } {
    set i 30
  }
}

# Print success message if loop succeeded.
if { $test_flag == 1 } {
  pass "threaded watch loop"
}

# Verify that we hit first watchpoint in main thread.
set message "first watchpoint on args\[0\] hit"
if { $args_0 > 0 } {
  pass $message
} else {
  fail $message
}

# Verify that we hit second watchpoint in main thread.
set message "first watchpoint on args\[1\] hit"
if { $args_1 > 0 } {
  pass $message
} else {
  fail $message
}

# Verify that we hit first watchpoint in child thread.
set message "watchpoint on args\[0\] hit in thread"
if { $args_0 > 1 } {
  pass $message
} else {
  fail $message
}

# Verify that we hit second watchpoint in child thread.
set message "watchpoint on args\[1\] hit in thread"
if { $args_1 > 1 } {
  pass $message
} else {
  fail $message
}

# Verify that all watchpoint hits are accounted for.
set message "combination of threaded watchpoints = 30"
if { [target_no_stopped_data] } {
    # See above.  If we allow two watchpoints to be hit at once, we
    # may have more than 30 hits total.
    set result [expr $args_0 + $args_1 >= 30]
} else {
    set result [expr $args_0 + $args_1 == 30]
}
if { $result } {
  pass $message
} else {
  fail $message
}