summaryrefslogtreecommitdiff
path: root/gdb/testsuite/gdb.dwarf2/var-access.exp
blob: 91a29bd988602337e21986f48fcb4dad95b3f688 (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
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
235
236
237
238
239
240
241
242
243
244
245
246
247
248
249
250
251
252
253
254
255
256
257
258
259
260
261
262
263
264
265
266
267
268
269
270
271
272
273
274
275
276
277
278
279
280
281
282
283
284
285
286
287
288
289
290
291
292
293
294
295
296
297
298
299
300
301
302
303
304
305
306
307
308
309
310
311
312
313
314
315
316
317
318
319
320
321
322
323
324
325
326
327
328
329
330
331
332
333
334
335
336
337
338
339
340
341
342
343
344
345
# Copyright 2017-2018 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/>.

# Test reading/writing variables with non-trivial DWARF locations.  In
# particular the test uses register- and memory locations as well as
# composite locations with register- and memory pieces.

load_lib dwarf.exp

# This test can only be run on targets which support DWARF-2 and use gas.
if {![dwarf2_support]} {
    return 0
}

# Choose suitable integer registers for the test.

set dwarf_regnum {0 1}

if { [is_aarch64_target] } {
    set regname {x0 x1}
} elseif { [is_aarch32_target]
	   || [istarget "s390*-*-*" ]
	   || [istarget "powerpc*-*-*"]
	   || [istarget "rs6000*-*-aix*"] } {
    set regname {r0 r1}
} elseif { [is_x86_like_target] } {
    set regname {eax ecx}
} elseif { [is_amd64_regs_target] } {
    set regname {rax rdx}
} else {
    verbose "Skipping tests for accessing DWARF-described variables."
    return
}

standard_testfile .c ${gdb_test_file_name}-dw.S

# Make some DWARF for the test.

set asm_file [standard_output_file $srcfile2]
Dwarf::assemble $asm_file {
    global srcdir subdir srcfile
    global dwarf_regnum regname

    set buf_var [gdb_target_symbol buf]

    cu {} {
	DW_TAG_compile_unit {
		{DW_AT_name var-pieces-dw.c}
		{DW_AT_comp_dir /tmp}
	} {
	    declare_labels char_type_label
	    declare_labels int_type_label short_type_label
	    declare_labels array_a8_label struct_s_label struct_t_label
	    declare_labels struct_st_label

	    # char
	    char_type_label: base_type {
		{name "char"}
		{encoding @DW_ATE_unsigned_char}
		{byte_size 1 DW_FORM_sdata}
	    }

	    # int
	    int_type_label: base_type {
		{name "int"}
		{encoding @DW_ATE_signed}
		{byte_size 4 DW_FORM_sdata}
	    }

	    # char [8]
	    array_a8_label: array_type {
		{type :$char_type_label}
	    } {
		subrange_type {
		    {type :$int_type_label}
		    {upper_bound 7 DW_FORM_udata}
		}
	    }

	    # struct s { char a, b, c, d; };
	    struct_s_label: structure_type {
		{name "s"}
		{byte_size 4 DW_FORM_sdata}
	    } {
		member {
		    {name "a"}
		    {type :$char_type_label}
		    {data_member_location 0 DW_FORM_udata}
		}
		member {
		    {name "b"}
		    {type :$char_type_label}
		    {data_member_location 1 DW_FORM_udata}
		}
		member {
		    {name "c"}
		    {type :$char_type_label}
		    {data_member_location 2 DW_FORM_udata}
		}
		member {
		    {name "d"}
		    {type :$char_type_label}
		    {data_member_location 3 DW_FORM_udata}
		}
	    }

	    # struct t { int u, x:9, y:13, z:10; };
	    struct_t_label: structure_type {
		{name "t"}
		{byte_size 8 DW_FORM_sdata}
	    } {
		member {
		    {name "u"}
		    {type :$int_type_label}
		}
		member {
		    {name "x"}
		    {type :$int_type_label}
		    {data_member_location 4 DW_FORM_udata}
		    {bit_size 9 DW_FORM_udata}
		}
		member {
		    {name "y"}
		    {type :$int_type_label}
		    {data_bit_offset 41 DW_FORM_udata}
		    {bit_size 13 DW_FORM_udata}
		}
		member {
		    {name "z"}
		    {type :$int_type_label}
		    {data_bit_offset 54 DW_FORM_udata}
		    {bit_size 10 DW_FORM_udata}
		}
	    }

	    # struct st { struct s s; struct t t; };
	    struct_st_label: structure_type {
		{name "st"}
		{byte_size 12 DW_FORM_udata}
	    } {
		member {
		    {name "s"}
		    {type :$struct_s_label}
		}
		member {
		    {name "t"}
		    {type :$struct_t_label}
		    {data_member_location 4 DW_FORM_udata}
		}
	    }

	    DW_TAG_subprogram {
		{MACRO_AT_func { main ${srcdir}/${subdir}/${srcfile} }}
		{DW_AT_external 1 flag}
	    } {
		# Simple memory location.
		DW_TAG_variable {
		    {name "a"}
		    {type :$array_a8_label}
		    {location {
			addr $buf_var
		    } SPECIAL_expr}
		}
		# Memory pieces: two bytes from &buf[2], and two bytes
		# from &buf[0].
		DW_TAG_variable {
		    {name "s1"}
		    {type :$struct_s_label}
		    {location {
			addr $buf_var
			plus_uconst 2
			piece 2
			addr $buf_var
			piece 2
		    } SPECIAL_expr}
		}
		# Register- and memory pieces: one byte each from r0,
		# &buf[4], r1, and &buf[5].
		DW_TAG_variable {
		    {name "s2"}
		    {type :$struct_s_label}
		    {location {
			regx [lindex $dwarf_regnum 0]
			piece 1
			addr "$buf_var + 4"
			piece 1
			regx [lindex $dwarf_regnum 1]
			piece 1
			addr "$buf_var + 5"
			piece 1
		    } SPECIAL_expr}
		}
		# Memory pieces for bitfield access: 8 bytes optimized
		# out, 3 bytes from &buf[3], and 1 byte from &buf[1].
		DW_TAG_variable {
		    {name "st1"}
		    {type :$struct_st_label}
		    {location {
			piece 8
			addr "$buf_var + 3"
			piece 3
			addr "$buf_var + 1"
			piece 1
		    } SPECIAL_expr}
		}
		# Register pieces for bitfield access: 4 bytes optimized
		# out, 3 bytes from r0, and 1 byte from r1.
		DW_TAG_variable {
		    {name "t2"}
		    {type :$struct_t_label}
		    {location {
			piece 4
			regx [lindex $dwarf_regnum 0]
			piece 3
			regx [lindex $dwarf_regnum 1]
			piece 1
		    } SPECIAL_expr}
		}
		# One piece per bitfield, using piece offsets: 32 bits of
		# an implicit value, 9 bits of a stack value, 13 bits of
		# r0, and 10 bits of buf.
		DW_TAG_variable {
		    {name "t3"}
		    {type :$struct_t_label}
		    {location {
			implicit_value 0x12 0x34 0x56 0x78 0x9a
			bit_piece 32 4
			const2s -280
			stack_value
			bit_piece 9 2
			regx [lindex $dwarf_regnum 0]
			bit_piece 13 14
			addr $buf_var
			bit_piece 10 42
		    } SPECIAL_expr}
		}
	    }
	}
    }
}

if { [prepare_for_testing ${testfile}.exp ${testfile} \
	  [list $srcfile $asm_file] {nodebug}] } {
    return -1
}

if ![runto_main] {
    return -1
}

# Determine byte order.
set endian [get_endianness]

# Byte-aligned memory pieces.
gdb_test "print/d s1" " = \\{a = 2, b = 3, c = 0, d = 1\\}" \
    "s1 == re-ordered buf"
gdb_test_no_output "set var s1.a = 63"
gdb_test "print/d s1" " = \\{a = 63, b = 3, c = 0, d = 1\\}" \
    "verify s1.a"
gdb_test "print/d a" " = \\{0, 1, 63, 3, 4, 5, 6, 7\\}" \
    "verify s1.a through a"
gdb_test_no_output "set var s1.b = 42"
gdb_test "print/d s1" " = \\{a = 63, b = 42, c = 0, d = 1\\}" \
    "verify s1.b"
gdb_test "print/d a" " = \\{0, 1, 63, 42, 4, 5, 6, 7\\}" \
    "verify s1.b through a"

# Byte-aligned register- and memory pieces.
gdb_test_no_output "set var \$[lindex $regname 0] = 81" \
    "init reg for s2.a"
gdb_test_no_output "set var \$[lindex $regname 1] = 28" \
    "init reg for s2.c"
gdb_test "print/u s2" " = \\{a = 81, b = 4, c = 28, d = 5\\}" \
    "initialized s2 from mem and regs"
gdb_test_no_output "set var s2.c += s2.a + s2.b - s2.d"
gdb_test "print/u s2" " = \\{a = 81, b = 4, c = 108, d = 5\\}" \
    "verify s2.c"
gdb_test "print/u \$[lindex $regname 1]" " = 108" \
    "verify s2.c through reg"
gdb_test_no_output "set var s2 = {191, 73, 231, 123}" \
    "re-initialize s2"
gdb_test "print/u s2"  " = \\{a = 191, b = 73, c = 231, d = 123\\}" \
    "verify re-initialized s2"

# Unaligned bitfield access through byte-aligned pieces.
gdb_test_no_output "set var a = { 0 }"
gdb_test_no_output "set var st1.t.x = -7"
gdb_test_no_output "set var st1.t.z = 340"
gdb_test_no_output "set var st1.t.y = 1234"
gdb_test "print st1.t" " = \\{u = <optimized out>, x = -7, y = 1234, z = 340\\}" \
    "verify st1.t"
switch $endian {
    little {set val "0x55, 0x0, 0xf9, 0xa5, 0x9"}
    big {set val "0x54, 0x0, 0xfc, 0x93, 0x49"}
}
# | -- | z:2-9 | -- | x:0-7 | x:8 y:0-6 | y:7-12 z:0-1 | -- | -- |
#      \_______________________________________________/
#                             val
gdb_test "print/x a" " = \\{0x0, ${val}, 0x0, 0x0\\}" \
    "verify st1 through a"

switch $endian { big {set val 0x7ffc} little {set val 0x3ffe00} }
gdb_test_no_output "set var \$[lindex $regname 0] = $val" \
    "init t2, first piece"
gdb_test_no_output "set var \$[lindex $regname 1] = 0" \
    "init t2, second piece"
gdb_test "print/d t2" " = \\{u = <optimized out>, x = 0, y = -1, z = 0\\}" \
    "initialized t2 from regs"
gdb_test_no_output "set var t2.y = 2641"
gdb_test_no_output "set var t2.z = -400"
gdb_test_no_output "set var t2.x = 200"
gdb_test "print t2.x + t2.y + t2.z" " = 2441"

# Bitfield access through pieces with nonzero piece offsets.
gdb_test_no_output "set var \$[lindex $regname 0] = 0xa8000" \
    "init reg for t3.y"
gdb_test_no_output "set var *(char \[2\] *) (a + 5) = { 70, 82 }" \
    "init mem for t3.z"
switch $endian {
    little {set val "u = -1484430527, x = -70, y = 42, z = 145"}
    big {set val "u = 591751049, x = -70, y = 42, z = 101"}
}
gdb_test "print t3" " = \\{$val\\}" \
    "initialized t3 from reg and mem"
gdb_test_no_output "set var t3.y = -1" \
    "overwrite t3.y"
gdb_test "print/x \$[lindex $regname 0]" " = 0x7ffc000" \
    "verify t3.y through reg"
gdb_test_no_output "set var t3.z = -614" \
    "overwrite t3.z"
switch $endian {big {set val "0x59, 0xa2"} little {set val "0x6a, 0x56"}}
gdb_test "print/x *(char \[2\] *) (a + 5)" " = \\{$val\\}" \
    "verify t3.z through mem"