1# This testcase is part of GDB, the GNU debugger.
2
3# Copyright 2009-2020 Free Software Foundation, Inc.
4
5# This program is free software; you can redistribute it and/or modify
6# it under the terms of the GNU General Public License as published by
7# the Free Software Foundation; either version 3 of the License, or
8# (at your option) any later version.
9#
10# This program is distributed in the hope that it will be useful,
11# but WITHOUT ANY WARRANTY; without even the implied warranty of
12# MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
13# GNU General Public License for more details.
14#
15# You should have received a copy of the GNU General Public License
16# along with this program.  If not, see <http://www.gnu.org/licenses/>.
17
18# Test GDB can cope with two watchpoints being hit by different threads at the
19# same time, GDB reports one of them and after "continue" to report the other
20# one GDB should not be confused by differently set watchpoints that time.
21# This is the goal of "reorder1".  "reorder0" tests the basic functionality of
22# two watchpoints being hit at the same time, without reordering them during the
23# stop.  The formerly broken functionality is due to the all-stop mode default
24# "show breakpoint always-inserted" being "off".  Formerly the remembered hit
25# could be assigned during continuation of a thread with pending SIGTRAP to the
26# different/new watchpoint, just based on the watchpoint/debug register number.
27
28if {[skip_hw_watchpoint_access_tests]
29    || [skip_hw_watchpoint_multi_tests]
30    || ![istarget *-*-linux*]} {
31    return 0
32}
33
34standard_testfile
35if {[gdb_compile_pthreads "${srcdir}/${subdir}/${srcfile}" ${binfile} executable [list debug additional_flags=-lrt]] != "" } {
36    return -1
37}
38
39foreach reorder {0 1} { with_test_prefix "reorder$reorder" {
40
41    clean_restart $testfile
42
43    gdb_test "set can-use-hw-watchpoints 1"
44
45    if ![runto_main] {
46	return -1
47    }
48
49    # Use "rwatch" as "watch" would report the watchpoint changed just based on its
50    # read memory value during a stop by unrelated event.  We are interested in not
51    # losing the hardware watchpoint trigger.
52
53    gdb_test "rwatch thread1_rwatch" "Hardware read watchpoint \[0-9\]+: thread1_rwatch"
54    set test "rwatch thread2_rwatch"
55    gdb_test_multiple $test $test {
56	-re "Target does not support this type of hardware watchpoint\\.\r\n$gdb_prompt $" {
57	    # ppc64 supports at most 1 hw watchpoints.
58	    unsupported $test
59	    return
60	}
61	-re "Hardware read watchpoint \[0-9\]+: thread2_rwatch\r\n$gdb_prompt $" {
62	    pass $test
63	}
64    }
65    gdb_breakpoint [gdb_get_line_number "break-at-exit"]
66
67    # The watchpoints can happen in arbitrary order depending on random:
68    # SEL: Found 2 SIGTRAP events, selecting #[01]
69    # As GDB contains no srand() on the specific host/OS it will behave always the
70    # same.  Such order cannot be guaranteed for GDB in general.
71
72    gdb_test "continue" \
73	     "Hardware read watchpoint \[0-9\]+: thread\[12\]_rwatch\r\n\r\nValue = 0\r\n0x\[0-9a-f\]+ in thread\[12\]_func .*" \
74	     "continue a"
75
76    if $reorder {
77	# GDB orders watchpoints by their addresses so inserting new variables
78	# with lower addresses will shift the former watchpoints to higher
79	# debug registers.
80
81	gdb_test "rwatch unused1_rwatch" "Hardware read watchpoint \[0-9\]+: unused1_rwatch"
82	gdb_test "rwatch unused2_rwatch" "Hardware read watchpoint \[0-9\]+: unused2_rwatch"
83    }
84
85    gdb_test "continue" \
86	     "Hardware read watchpoint \[0-9\]+: thread\[12\]_rwatch\r\n\r\nValue = 0\r\n0x\[0-9a-f\]+ in thread\[12\]_func .*" \
87	     "continue b"
88
89    # While the debug output itself is not checked in this testcase one bug was
90    # found in the DEBUG_INFRUN code path.
91    gdb_test "set debug infrun 1"
92
93    gdb_continue_to_breakpoint "break-at-exit" ".*break-at-exit.*"
94}}
95