summaryrefslogtreecommitdiff
path: root/gdb/testsuite/gdb.base/recurse.exp
blob: cd1b698d8a859709b64fd3c4852760b7158ef385 (plain)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
# Copyright 1992, 1994, 1995, 1996, 1997, 1999, 2000, 2007, 2008, 2009, 2010
# 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 was written by Jeff Law. (law@cs.utah.edu)

if $tracelevel then {
    strace $tracelevel
}

set prms_id 0
set bug_id 0

set testfile "recurse"
set srcfile ${testfile}.c
set binfile ${objdir}/${subdir}/${testfile}
if  { [gdb_compile "${srcdir}/${subdir}/${srcfile}" "${binfile}" executable {debug}] != "" } {
     untested recurse.exp
     return -1
}

# Start with a fresh gdb.

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

proc recurse_tests {} {

    # Disable hardware watchpoints if necessary.
    if [target_info exists gdb,no_hardware_watchpoints] {
	gdb_test "set can-use-hw-watchpoints 0" "" ""
    }

    if [runto recurse] then {
	# First we need to step over the assignment of b, so it has a known
	# value.
	gdb_test "next" "if \\(a == 1\\)" "next over b = 0 in first instance"
	gdb_test "watch b" ".*\[Ww\]atchpoint \[0-9]*: b" \
	    "set first instance watchpoint"

	# Continue until initial set of b.
	if [gdb_test "continue" \
	    "Continuing.*\[Ww\]atchpoint.*: b.*Old value = 0.*New value = 10.*" \
	    "continue to first instance watchpoint, first time"] then {
	    gdb_suppress_tests;
	}

	# Continue inward for a few iterations
	gdb_test "continue" "Breakpoint.* recurse \\(a=9\\).*" \
	    "continue to recurse (a = 9)"
	gdb_test "continue" "Breakpoint.* recurse \\(a=8\\).*" \
	    "continue to recurse (a = 8)"
	gdb_test "continue" "Breakpoint.* recurse \\(a=7\\).*" \
	    "continue to recurse (a = 7)"
	gdb_test "continue" "Breakpoint.* recurse \\(a=6\\).*" \
	    "continue to recurse (a = 6)"
	gdb_test "continue" "Breakpoint.* recurse \\(a=5\\).*" \
	    "continue to recurse (a = 5)"

	# Put a watchpoint on another instance of b
	# First we need to step over the assignment of b, so it has a known
	# value.
	gdb_test "next" "if \\(a == 1\\)" "next over b = 0 in second instance"
	gdb_test "watch b" ".*\[Ww\]atchpoint \[0-9]*: b" \
	    "set second instance watchpoint"

	# Continue until initial set of b (second instance).
	if [gdb_test "continue" \
	    "Continuing.*\[Ww\]atchpoint.*: b.*Old value = 0.*New value = 5.*"\
	    "continue to second instance watchpoint, first time"] then {
	gdb_suppress_tests;
	}

	# Continue inward for a few iterations
	gdb_test "continue" "Breakpoint.* recurse \\(a=4\\).*" \
	    "continue to recurse (a = 4)"
	gdb_test "continue" "Breakpoint.* recurse \\(a=3\\).*" \
	    "continue to recurse (a = 3)"
	gdb_test "continue" "Breakpoint.* recurse \\(a=2\\).*" \
	    "continue to recurse (a = 2)"
	gdb_test "continue" "Breakpoint.* recurse \\(a=1\\).*" \
	    "continue to recurse (a = 1)"

	# Continue until second set of b (second instance).
	if [gdb_test "continue" \
	    "Continuing.*\[Ww\]atchpoint.*: b.*Old value = 5.*New value = 120.*return.*" \
	    "continue to second instance watchpoint, second time"] then { 
	    gdb_suppress_tests;
	}

	# Continue again.  We should have a watchpoint go out of scope now
	if [gdb_test "continue" \
	    "Continuing.*\[Ww\]atchpoint.*deleted.*recurse \\(a=6\\) .*" \
	    "second instance watchpoint deleted when leaving scope"] then {
	    gdb_suppress_tests;
	}

	# Continue until second set of b (first instance).
	# 24320 is allowed as the final value for b as that's the value
	# b would have on systems with 16bit integers.
	#
	# We could fix the test program to deal with this too.
	if [gdb_test "continue" \
	    "Continuing.*\[Ww\]atchpoint.*b.*Old value = 10.*New value = \(3628800|24320\).*return.*" \
	    "continue to first instance watchpoint, second time"] then {
	    gdb_suppress_tests
	}

	# Continue again.  We should have a watchpoint go out of scope now.
	#
	# The former version expected the test to return to main().
	# Now it expects the test to return to main or to stop in the
	# function's epilogue.
	# 
	# The problem is that gdb needs to (but doesn't) understand
	# function epilogues in the same way as for prologues.
	# 
	# If there is no hardware watchpoint (such as a x86 debug register),
	# then watchpoints are done "the hard way" by single-stepping the
	# target until the value of the watched variable changes.  If you
	# are single-stepping, you will eventually step into an epilogue.
	# When you do that, the "top" stack frame may become partially
	# deconstructed (as when you pop the frame pointer, for instance),
	# and from that point on, GDB can no longer make sense of the stack.
	# 
	# A test which stops in the epilogue is trying to determine when GDB
	# leaves the stack frame in which the watchpoint was created.  It does
	# this basically by watching for the frame pointer to change.  When
	# the frame pointer changes, the test expects to be back in main, but
	# instead it is still in the epilogue of the callee.
	if [gdb_test "continue" \
	    "Continuing.*\[Ww\]atchpoint.*deleted.*\(main \\(\\) \|21.*\}\).*" \
	    "first instance watchpoint deleted when leaving scope"] then {
	    gdb_suppress_tests;
	}
    }
    gdb_stop_suppressing_tests;
}

# Preserve the old timeout, and set a new one that should be
# sufficient to avoid timing out during this test.
set oldtimeout $timeout
set timeout [expr "$timeout + 60"]
verbose "Timeout is now $timeout seconds" 2

recurse_tests

# Restore the preserved old timeout value.
set timeout $oldtimeout
verbose "Timeout is now $timeout seconds" 2