xref: /netbsd-src/external/gpl3/gdb.old/dist/gdb/testsuite/gdb.base/watchpoint-reuse-slot.exp (revision 9616dacfef448e70e3fbbd865bddf60d54b656c5)
1# Copyright 2014-2015 Free Software Foundation, Inc.
2
3# This program is free software; you can redistribute it and/or modify
4# it under the terms of the GNU General Public License as published by
5# the Free Software Foundation; either version 3 of the License, or
6# (at your option) any later version.
7#
8# This program is distributed in the hope that it will be useful,
9# but WITHOUT ANY WARRANTY; without even the implied warranty of
10# MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
11# GNU General Public License for more details.
12#
13# You should have received a copy of the GNU General Public License
14# along with this program.  If not, see <http://www.gnu.org/licenses/>.
15
16# Test alternating between watchpoint types, watching a sliding window
17# of addresses (thus alternating between aligned and unaligned
18# addresses).  Only a single watchpoint exists at any given time.  On
19# targets that only update the debug registers on resume, this
20# stresses the debug register setup code, both in GDB and in the
21# target/kernel as one watchpoint replaces the other in a single
22# operation.  (Note that we don't have any of these watchpoints
23# trigger.)
24
25if [target_info exists gdb,no_hardware_watchpoints] {
26    unsupported "no target support"
27    return
28}
29
30standard_testfile
31
32if {[prepare_for_testing "failed to prepare" $testfile $srcfile debug]} {
33    return -1
34}
35
36if ![runto_main] then {
37    fail "Can't run to main"
38    return 0
39}
40
41# The line we'll be stepping.
42set srcline [gdb_get_line_number "stepi line"]
43
44# The address the program is stopped at currently.
45set cur_addr ""
46
47# Get the current PC.
48
49proc get_pc {} {
50    global hex gdb_prompt
51
52    set addr ""
53    set test "get PC"
54    gdb_test_multiple "p /x \$pc" "$test" {
55	-re " = ($hex).*$gdb_prompt $" {
56	    set addr $expect_out(1,string)
57	    pass "$test"
58	}
59    }
60
61    return $addr
62}
63
64
65# Issue a stepi, and make sure the program advanced past the current
66# instruction (stored in the CUR_ADDR global).
67
68proc stepi {} {
69    global hex gdb_prompt cur_addr
70
71    set srcline "  for (i = 0; i < 100000; i++); /* stepi line */"
72    set test "stepi advanced"
73    gdb_test_multiple "stepi" $test {
74	-re "($hex).*[string_to_regexp $srcline]\r\n$gdb_prompt $" {
75	    set addr $expect_out(1,string)
76	    if {$addr != $cur_addr} {
77		pass $test
78	    } else {
79		fail $test
80	    }
81	    set cur_addr addr
82	}
83    }
84}
85
86gdb_breakpoint $srcline
87gdb_continue_to_breakpoint "stepi line"
88
89# The test tries various sequences of different types of watchpoints.
90# Probe for support first.
91
92# So we get an immediate warning/error if the target doesn't support a
93# given watchpoint type.
94gdb_test_no_output "set breakpoint always-inserted on"
95
96# The list of supported commands.  Below we'll probe for support and
97# add elements to this list.
98set cmds {}
99
100foreach cmd {"watch" "awatch" "rwatch"} {
101    set test $cmd
102    gdb_test_multiple "$cmd buf.byte\[0\]" $test {
103	-re "You may have requested too many.*$gdb_prompt $" {
104	    unsupported $test
105	}
106	-re "Target does not support.*$gdb_prompt $" {
107	    unsupported $test
108	}
109	-re "$gdb_prompt $" {
110	    pass $test
111	    lappend cmds $cmd
112	}
113    }
114
115   delete_breakpoints
116}
117
118set test "hbreak"
119gdb_test_multiple "hbreak main" $test {
120    -re "You may have requested too many.*$gdb_prompt $" {
121	unsupported $test
122    }
123    -re "No hardware breakpoint support.*$gdb_prompt $" {
124	unsupported $test
125    }
126    -re "$gdb_prompt $" {
127	pass $test
128	lappend cmds "hbreak"
129    }
130}
131
132delete_breakpoints
133
134set cur_addr [get_pc]
135
136# Return true if the memory range [buf.byte + OFFSET, +WIDTH] can be
137# monitored by CMD, otherwise return false.
138
139proc valid_addr_p {cmd offset width} {
140
141    if { [istarget "aarch64*-*-linux*"] } {
142	# The aarch64 Linux kernel port only accepts 4-byte aligned addresses
143	# for hardware breakpoints and 8-byte aligned addresses for hardware
144	# watchpoints.  However, both GDB and GDBserver support unaligned
145	# watchpoints by using more than one properly aligned watchpoint
146	# registers to represent the whole unaligned region.  Breakpoint
147	# addresses must still be aligned though.
148	if {$cmd == "hbreak" } {
149	    if { [expr ($offset) % 4] != 0 } {
150		return 0
151	    }
152	}
153    } elseif { [istarget "arm*-*-linux*"] } {
154	if { $cmd == "hbreak" } {
155	    # Breakpoints must be of length 2 (thumb) or 4 (ARM) bytes.
156	    if { $width != 2 && $width != 4 } {
157		return 0
158	    }
159	} else {
160	    # Watchpoints can be of length 1, 2, 4 or 8 bytes.
161	    if { [expr $width % 2] != 0 } {
162		return 0
163	    }
164	}
165
166	if { [expr ($offset) % 8] == 0 && $width == 8 } {
167	    # If WIDTH is 8 byte, the address should be 8-byte aligned.
168	    return 1
169	} elseif { [expr ($offset) % 4] == 0 } {
170	    return 1
171	} elseif { [expr ($offset) % 4] == 2 && $width == 2 } {
172	    # Halfword watchpoints and breakpoints.
173	    return 1
174	} elseif { [expr ($offset) % 4] == 1 && $width == 1 && $cmd != "hbreak" } {
175	    # Single byte watchpoints.
176	    return 1
177	} else {
178	    return 0
179	}
180    }
181
182    return 1
183}
184
185# Watch WIDTH bytes at BASE + OFFSET.  CMD specifices the specific
186# type of watchpoint to use.  If CMD is "hbreak", WIDTH is ignored.
187
188proc watch_command {cmd base offset width} {
189    global srcfile srcline hex
190
191    if {$cmd == "hbreak"} {
192	set expr "*(buf.byte + $base + $offset)"
193	gdb_test "hbreak $expr" "Hardware assisted breakpoint \[0-9\]+ at $hex"
194    } elseif {$cmd == "watch"} {
195	set expr "*(buf.byte + $base + $offset)@$width"
196	gdb_test "$cmd $expr" \
197	    "Hardware watchpoint \[0-9\]+: [string_to_regexp $expr]"
198    } elseif {$cmd == "awatch"} {
199	set expr "*(buf.byte + $base + $offset)@$width"
200	gdb_test "$cmd $expr" \
201	    "Hardware access \\(read/write\\) watchpoint \[0-9\]+: [string_to_regexp $expr]"
202    } elseif {$cmd == "rwatch"} {
203	set expr "*(buf.byte + $base + $offset)@$width"
204	gdb_test "$cmd $expr" \
205	    "Hardware read watchpoint \[0-9\]+: [string_to_regexp $expr]"
206    }
207}
208
209# Run test proper.  See intro for description.
210
211foreach always_inserted {"off" "on" } {
212    gdb_test_no_output "set breakpoint always-inserted $always_inserted"
213    foreach cmd1 $cmds {
214	foreach cmd2 $cmds {
215	    for {set width 1} {$width < 4} {incr width} {
216
217		if {$cmd1 == "hbreak" && $cmd2 == "hbreak" && $width > 1} {
218		    # hbreak ignores WIDTH, no use testing more than
219		    # once.
220		    continue
221		}
222
223		for {set x 0} {$x < 4} {incr x} {
224
225		    if { ![valid_addr_p $cmd1 $x $width]
226			 || ![valid_addr_p $cmd2 $x+1 $width] } {
227			# Skip tests if requested address or length
228			# of breakpoint or watchpoint don't meet
229			# target or kernel requirements.
230			continue
231		    }
232
233		    set prefix "always-inserted $always_inserted: "
234		    append prefix "$cmd1 x $cmd2: "
235		    with_test_prefix "$prefix: width $width, iter $x" {
236			with_test_prefix "base + 0" {
237			    watch_command $cmd1 $x 0 $width
238			    stepi
239			    gdb_test_no_output "delete \$bpnum"
240			}
241			with_test_prefix "base + 1" {
242			    watch_command $cmd2 $x 1 $width
243			    stepi
244			    gdb_test_no_output "delete \$bpnum"
245			}
246		    }
247		}
248	    }
249	}
250    }
251}
252