Commit | Line | Data |
---|---|---|
c906108c | 1 | /* Find a variable's value in memory, for GDB, the GNU debugger. |
1bac305b | 2 | |
ecd75fc8 | 3 | Copyright (C) 1986-2014 Free Software Foundation, Inc. |
c906108c | 4 | |
c5aa993b | 5 | This file is part of GDB. |
c906108c | 6 | |
c5aa993b JM |
7 | This program is free software; you can redistribute it and/or modify |
8 | it under the terms of the GNU General Public License as published by | |
a9762ec7 | 9 | the Free Software Foundation; either version 3 of the License, or |
c5aa993b | 10 | (at your option) any later version. |
c906108c | 11 | |
c5aa993b JM |
12 | This program is distributed in the hope that it will be useful, |
13 | but WITHOUT ANY WARRANTY; without even the implied warranty of | |
14 | MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the | |
15 | GNU General Public License for more details. | |
c906108c | 16 | |
c5aa993b | 17 | You should have received a copy of the GNU General Public License |
a9762ec7 | 18 | along with this program. If not, see <http://www.gnu.org/licenses/>. */ |
c906108c SS |
19 | |
20 | #include "defs.h" | |
21 | #include "symtab.h" | |
22 | #include "gdbtypes.h" | |
23 | #include "frame.h" | |
24 | #include "value.h" | |
25 | #include "gdbcore.h" | |
26 | #include "inferior.h" | |
27 | #include "target.h" | |
0e9f083f | 28 | #include <string.h> |
14e534aa | 29 | #include "gdb_assert.h" |
c906108c | 30 | #include "floatformat.h" |
c5aa993b | 31 | #include "symfile.h" /* for overlay functions */ |
4e052eda | 32 | #include "regcache.h" |
eb8bc282 | 33 | #include "user-regs.h" |
fe898f56 | 34 | #include "block.h" |
e0740f77 | 35 | #include "objfiles.h" |
a5ee536b | 36 | #include "language.h" |
c906108c | 37 | |
9659616a MS |
38 | /* Basic byte-swapping routines. All 'extract' functions return a |
39 | host-format integer from a target-format integer at ADDR which is | |
40 | LEN bytes long. */ | |
c906108c SS |
41 | |
42 | #if TARGET_CHAR_BIT != 8 || HOST_CHAR_BIT != 8 | |
43 | /* 8 bit characters are a pretty safe assumption these days, so we | |
44 | assume it throughout all these swapping routines. If we had to deal with | |
45 | 9 bit characters, we would need to make len be in bits and would have | |
46 | to re-write these routines... */ | |
c5aa993b | 47 | you lose |
c906108c SS |
48 | #endif |
49 | ||
a9ac8f51 | 50 | LONGEST |
e17a4113 UW |
51 | extract_signed_integer (const gdb_byte *addr, int len, |
52 | enum bfd_endian byte_order) | |
c906108c SS |
53 | { |
54 | LONGEST retval; | |
37611a2b AC |
55 | const unsigned char *p; |
56 | const unsigned char *startaddr = addr; | |
57 | const unsigned char *endaddr = startaddr + len; | |
c906108c SS |
58 | |
59 | if (len > (int) sizeof (LONGEST)) | |
8a3fe4f8 AC |
60 | error (_("\ |
61 | That operation is not available on integers of more than %d bytes."), | |
baa6f10b | 62 | (int) sizeof (LONGEST)); |
c906108c SS |
63 | |
64 | /* Start at the most significant end of the integer, and work towards | |
65 | the least significant. */ | |
e17a4113 | 66 | if (byte_order == BFD_ENDIAN_BIG) |
c906108c SS |
67 | { |
68 | p = startaddr; | |
69 | /* Do the sign extension once at the start. */ | |
c5aa993b | 70 | retval = ((LONGEST) * p ^ 0x80) - 0x80; |
c906108c SS |
71 | for (++p; p < endaddr; ++p) |
72 | retval = (retval << 8) | *p; | |
73 | } | |
74 | else | |
75 | { | |
76 | p = endaddr - 1; | |
77 | /* Do the sign extension once at the start. */ | |
c5aa993b | 78 | retval = ((LONGEST) * p ^ 0x80) - 0x80; |
c906108c SS |
79 | for (--p; p >= startaddr; --p) |
80 | retval = (retval << 8) | *p; | |
81 | } | |
82 | return retval; | |
83 | } | |
84 | ||
85 | ULONGEST | |
e17a4113 UW |
86 | extract_unsigned_integer (const gdb_byte *addr, int len, |
87 | enum bfd_endian byte_order) | |
c906108c SS |
88 | { |
89 | ULONGEST retval; | |
37611a2b AC |
90 | const unsigned char *p; |
91 | const unsigned char *startaddr = addr; | |
92 | const unsigned char *endaddr = startaddr + len; | |
c906108c SS |
93 | |
94 | if (len > (int) sizeof (ULONGEST)) | |
8a3fe4f8 AC |
95 | error (_("\ |
96 | That operation is not available on integers of more than %d bytes."), | |
baa6f10b | 97 | (int) sizeof (ULONGEST)); |
c906108c SS |
98 | |
99 | /* Start at the most significant end of the integer, and work towards | |
100 | the least significant. */ | |
101 | retval = 0; | |
e17a4113 | 102 | if (byte_order == BFD_ENDIAN_BIG) |
c906108c SS |
103 | { |
104 | for (p = startaddr; p < endaddr; ++p) | |
105 | retval = (retval << 8) | *p; | |
106 | } | |
107 | else | |
108 | { | |
109 | for (p = endaddr - 1; p >= startaddr; --p) | |
110 | retval = (retval << 8) | *p; | |
111 | } | |
112 | return retval; | |
113 | } | |
114 | ||
115 | /* Sometimes a long long unsigned integer can be extracted as a | |
116 | LONGEST value. This is done so that we can print these values | |
117 | better. If this integer can be converted to a LONGEST, this | |
118 | function returns 1 and sets *PVAL. Otherwise it returns 0. */ | |
119 | ||
120 | int | |
0d509538 | 121 | extract_long_unsigned_integer (const gdb_byte *addr, int orig_len, |
e17a4113 | 122 | enum bfd_endian byte_order, LONGEST *pval) |
c906108c | 123 | { |
0d509538 AC |
124 | const gdb_byte *p; |
125 | const gdb_byte *first_addr; | |
c906108c SS |
126 | int len; |
127 | ||
128 | len = orig_len; | |
e17a4113 | 129 | if (byte_order == BFD_ENDIAN_BIG) |
c906108c | 130 | { |
0d509538 AC |
131 | for (p = addr; |
132 | len > (int) sizeof (LONGEST) && p < addr + orig_len; | |
c906108c SS |
133 | p++) |
134 | { | |
135 | if (*p == 0) | |
136 | len--; | |
137 | else | |
138 | break; | |
139 | } | |
140 | first_addr = p; | |
141 | } | |
142 | else | |
143 | { | |
0d509538 AC |
144 | first_addr = addr; |
145 | for (p = addr + orig_len - 1; | |
146 | len > (int) sizeof (LONGEST) && p >= addr; | |
c906108c SS |
147 | p--) |
148 | { | |
149 | if (*p == 0) | |
150 | len--; | |
151 | else | |
152 | break; | |
153 | } | |
154 | } | |
155 | ||
156 | if (len <= (int) sizeof (LONGEST)) | |
157 | { | |
158 | *pval = (LONGEST) extract_unsigned_integer (first_addr, | |
e17a4113 UW |
159 | sizeof (LONGEST), |
160 | byte_order); | |
c906108c SS |
161 | return 1; |
162 | } | |
163 | ||
164 | return 0; | |
165 | } | |
166 | ||
4478b372 | 167 | |
4478b372 JB |
168 | /* Treat the bytes at BUF as a pointer of type TYPE, and return the |
169 | address it represents. */ | |
170 | CORE_ADDR | |
0d509538 | 171 | extract_typed_address (const gdb_byte *buf, struct type *type) |
4478b372 JB |
172 | { |
173 | if (TYPE_CODE (type) != TYPE_CODE_PTR | |
174 | && TYPE_CODE (type) != TYPE_CODE_REF) | |
8e65ff28 | 175 | internal_error (__FILE__, __LINE__, |
e2e0b3e5 AC |
176 | _("extract_typed_address: " |
177 | "type is not a pointer or reference")); | |
4478b372 | 178 | |
50810684 | 179 | return gdbarch_pointer_to_address (get_type_arch (type), type, buf); |
4478b372 JB |
180 | } |
181 | ||
9659616a MS |
182 | /* All 'store' functions accept a host-format integer and store a |
183 | target-format integer at ADDR which is LEN bytes long. */ | |
4478b372 | 184 | |
c906108c | 185 | void |
e17a4113 UW |
186 | store_signed_integer (gdb_byte *addr, int len, |
187 | enum bfd_endian byte_order, LONGEST val) | |
c906108c | 188 | { |
0d509538 AC |
189 | gdb_byte *p; |
190 | gdb_byte *startaddr = addr; | |
191 | gdb_byte *endaddr = startaddr + len; | |
c906108c SS |
192 | |
193 | /* Start at the least significant end of the integer, and work towards | |
194 | the most significant. */ | |
e17a4113 | 195 | if (byte_order == BFD_ENDIAN_BIG) |
c906108c SS |
196 | { |
197 | for (p = endaddr - 1; p >= startaddr; --p) | |
198 | { | |
199 | *p = val & 0xff; | |
200 | val >>= 8; | |
201 | } | |
202 | } | |
203 | else | |
204 | { | |
205 | for (p = startaddr; p < endaddr; ++p) | |
206 | { | |
207 | *p = val & 0xff; | |
208 | val >>= 8; | |
209 | } | |
210 | } | |
211 | } | |
212 | ||
213 | void | |
e17a4113 UW |
214 | store_unsigned_integer (gdb_byte *addr, int len, |
215 | enum bfd_endian byte_order, ULONGEST val) | |
c906108c SS |
216 | { |
217 | unsigned char *p; | |
c5aa993b | 218 | unsigned char *startaddr = (unsigned char *) addr; |
c906108c SS |
219 | unsigned char *endaddr = startaddr + len; |
220 | ||
221 | /* Start at the least significant end of the integer, and work towards | |
222 | the most significant. */ | |
e17a4113 | 223 | if (byte_order == BFD_ENDIAN_BIG) |
c906108c SS |
224 | { |
225 | for (p = endaddr - 1; p >= startaddr; --p) | |
226 | { | |
227 | *p = val & 0xff; | |
228 | val >>= 8; | |
229 | } | |
230 | } | |
231 | else | |
232 | { | |
233 | for (p = startaddr; p < endaddr; ++p) | |
234 | { | |
235 | *p = val & 0xff; | |
236 | val >>= 8; | |
237 | } | |
238 | } | |
239 | } | |
240 | ||
4478b372 JB |
241 | /* Store the address ADDR as a pointer of type TYPE at BUF, in target |
242 | form. */ | |
243 | void | |
0d509538 | 244 | store_typed_address (gdb_byte *buf, struct type *type, CORE_ADDR addr) |
4478b372 JB |
245 | { |
246 | if (TYPE_CODE (type) != TYPE_CODE_PTR | |
247 | && TYPE_CODE (type) != TYPE_CODE_REF) | |
8e65ff28 | 248 | internal_error (__FILE__, __LINE__, |
e2e0b3e5 AC |
249 | _("store_typed_address: " |
250 | "type is not a pointer or reference")); | |
4478b372 | 251 | |
50810684 | 252 | gdbarch_address_to_pointer (get_type_arch (type), type, buf, addr); |
4478b372 JB |
253 | } |
254 | ||
255 | ||
256 | ||
376c9600 AC |
257 | /* Return a `value' with the contents of (virtual or cooked) register |
258 | REGNUM as found in the specified FRAME. The register's type is | |
9c5ea4d9 | 259 | determined by register_type(). */ |
c906108c | 260 | |
3d6d86c6 | 261 | struct value * |
376c9600 | 262 | value_of_register (int regnum, struct frame_info *frame) |
c906108c | 263 | { |
e9e45075 | 264 | struct gdbarch *gdbarch = get_frame_arch (frame); |
3d6d86c6 | 265 | struct value *reg_val; |
c906108c | 266 | |
9564ee9f | 267 | /* User registers lie completely outside of the range of normal |
0406ec40 | 268 | registers. Catch them early so that the target never sees them. */ |
e9e45075 UW |
269 | if (regnum >= gdbarch_num_regs (gdbarch) |
270 | + gdbarch_num_pseudo_regs (gdbarch)) | |
eb8bc282 | 271 | return value_of_user_reg (regnum, frame); |
0406ec40 | 272 | |
d5b495b4 PA |
273 | reg_val = value_of_register_lazy (frame, regnum); |
274 | value_fetch_lazy (reg_val); | |
c906108c SS |
275 | return reg_val; |
276 | } | |
4478b372 | 277 | |
9214ee5f DJ |
278 | /* Return a `value' with the contents of (virtual or cooked) register |
279 | REGNUM as found in the specified FRAME. The register's type is | |
280 | determined by register_type(). The value is not fetched. */ | |
281 | ||
282 | struct value * | |
283 | value_of_register_lazy (struct frame_info *frame, int regnum) | |
284 | { | |
285 | struct gdbarch *gdbarch = get_frame_arch (frame); | |
286 | struct value *reg_val; | |
287 | ||
288 | gdb_assert (regnum < (gdbarch_num_regs (gdbarch) | |
289 | + gdbarch_num_pseudo_regs (gdbarch))); | |
290 | ||
291 | /* We should have a valid (i.e. non-sentinel) frame. */ | |
292 | gdb_assert (frame_id_p (get_frame_id (frame))); | |
293 | ||
41e8491f | 294 | reg_val = allocate_value_lazy (register_type (gdbarch, regnum)); |
9214ee5f DJ |
295 | VALUE_LVAL (reg_val) = lval_register; |
296 | VALUE_REGNUM (reg_val) = regnum; | |
297 | VALUE_FRAME_ID (reg_val) = get_frame_id (frame); | |
9214ee5f DJ |
298 | return reg_val; |
299 | } | |
300 | ||
4478b372 JB |
301 | /* Given a pointer of type TYPE in target form in BUF, return the |
302 | address it represents. */ | |
303 | CORE_ADDR | |
9898f801 UW |
304 | unsigned_pointer_to_address (struct gdbarch *gdbarch, |
305 | struct type *type, const gdb_byte *buf) | |
4478b372 | 306 | { |
e17a4113 | 307 | enum bfd_endian byte_order = gdbarch_byte_order (gdbarch); |
bb9bcb69 | 308 | |
e17a4113 | 309 | return extract_unsigned_integer (buf, TYPE_LENGTH (type), byte_order); |
4478b372 JB |
310 | } |
311 | ||
ac2e2ef7 | 312 | CORE_ADDR |
9898f801 UW |
313 | signed_pointer_to_address (struct gdbarch *gdbarch, |
314 | struct type *type, const gdb_byte *buf) | |
ac2e2ef7 | 315 | { |
e17a4113 | 316 | enum bfd_endian byte_order = gdbarch_byte_order (gdbarch); |
bb9bcb69 | 317 | |
e17a4113 | 318 | return extract_signed_integer (buf, TYPE_LENGTH (type), byte_order); |
ac2e2ef7 | 319 | } |
4478b372 JB |
320 | |
321 | /* Given an address, store it as a pointer of type TYPE in target | |
322 | format in BUF. */ | |
323 | void | |
9898f801 UW |
324 | unsigned_address_to_pointer (struct gdbarch *gdbarch, struct type *type, |
325 | gdb_byte *buf, CORE_ADDR addr) | |
4478b372 | 326 | { |
e17a4113 | 327 | enum bfd_endian byte_order = gdbarch_byte_order (gdbarch); |
bb9bcb69 | 328 | |
e17a4113 | 329 | store_unsigned_integer (buf, TYPE_LENGTH (type), byte_order, addr); |
4478b372 JB |
330 | } |
331 | ||
ac2e2ef7 | 332 | void |
9898f801 UW |
333 | address_to_signed_pointer (struct gdbarch *gdbarch, struct type *type, |
334 | gdb_byte *buf, CORE_ADDR addr) | |
ac2e2ef7 | 335 | { |
e17a4113 | 336 | enum bfd_endian byte_order = gdbarch_byte_order (gdbarch); |
bb9bcb69 | 337 | |
e17a4113 | 338 | store_signed_integer (buf, TYPE_LENGTH (type), byte_order, addr); |
ac2e2ef7 | 339 | } |
c906108c SS |
340 | \f |
341 | /* Will calling read_var_value or locate_var_value on SYM end | |
342 | up caring what frame it is being evaluated relative to? SYM must | |
343 | be non-NULL. */ | |
344 | int | |
fba45db2 | 345 | symbol_read_needs_frame (struct symbol *sym) |
c906108c | 346 | { |
24d6c2a0 TT |
347 | if (SYMBOL_COMPUTED_OPS (sym) != NULL) |
348 | return SYMBOL_COMPUTED_OPS (sym)->read_needs_frame (sym); | |
349 | ||
c906108c SS |
350 | switch (SYMBOL_CLASS (sym)) |
351 | { | |
352 | /* All cases listed explicitly so that gcc -Wall will detect it if | |
c5aa993b | 353 | we failed to consider one. */ |
4c2df51b | 354 | case LOC_COMPUTED: |
24d6c2a0 | 355 | gdb_assert_not_reached (_("LOC_COMPUTED variable missing a method")); |
4c2df51b | 356 | |
c906108c SS |
357 | case LOC_REGISTER: |
358 | case LOC_ARG: | |
359 | case LOC_REF_ARG: | |
c906108c SS |
360 | case LOC_REGPARM_ADDR: |
361 | case LOC_LOCAL: | |
c906108c SS |
362 | return 1; |
363 | ||
364 | case LOC_UNDEF: | |
365 | case LOC_CONST: | |
366 | case LOC_STATIC: | |
c906108c SS |
367 | case LOC_TYPEDEF: |
368 | ||
369 | case LOC_LABEL: | |
370 | /* Getting the address of a label can be done independently of the block, | |
c5aa993b JM |
371 | even if some *uses* of that address wouldn't work so well without |
372 | the right frame. */ | |
c906108c SS |
373 | |
374 | case LOC_BLOCK: | |
375 | case LOC_CONST_BYTES: | |
376 | case LOC_UNRESOLVED: | |
377 | case LOC_OPTIMIZED_OUT: | |
378 | return 0; | |
379 | } | |
380 | return 1; | |
381 | } | |
382 | ||
19630284 JB |
383 | /* Private data to be used with minsym_lookup_iterator_cb. */ |
384 | ||
385 | struct minsym_lookup_data | |
386 | { | |
387 | /* The name of the minimal symbol we are searching for. */ | |
388 | const char *name; | |
389 | ||
390 | /* The field where the callback should store the minimal symbol | |
391 | if found. It should be initialized to NULL before the search | |
392 | is started. */ | |
393 | struct minimal_symbol *result; | |
e27d198c TT |
394 | |
395 | /* The objfile in which the symbol was found. */ | |
396 | struct objfile *objfile; | |
19630284 JB |
397 | }; |
398 | ||
399 | /* A callback function for gdbarch_iterate_over_objfiles_in_search_order. | |
400 | It searches by name for a minimal symbol within the given OBJFILE. | |
401 | The arguments are passed via CB_DATA, which in reality is a pointer | |
402 | to struct minsym_lookup_data. */ | |
403 | ||
404 | static int | |
405 | minsym_lookup_iterator_cb (struct objfile *objfile, void *cb_data) | |
406 | { | |
407 | struct minsym_lookup_data *data = (struct minsym_lookup_data *) cb_data; | |
408 | ||
409 | gdb_assert (data->result == NULL); | |
410 | ||
411 | data->result = lookup_minimal_symbol (data->name, NULL, objfile); | |
e27d198c | 412 | data->objfile = objfile; |
19630284 JB |
413 | |
414 | /* The iterator should stop iff a match was found. */ | |
415 | return (data->result != NULL); | |
416 | } | |
417 | ||
a5ee536b JB |
418 | /* A default implementation for the "la_read_var_value" hook in |
419 | the language vector which should work in most situations. */ | |
c906108c | 420 | |
3d6d86c6 | 421 | struct value * |
a5ee536b | 422 | default_read_var_value (struct symbol *var, struct frame_info *frame) |
c906108c | 423 | { |
52f0bd74 | 424 | struct value *v; |
c906108c SS |
425 | struct type *type = SYMBOL_TYPE (var); |
426 | CORE_ADDR addr; | |
c906108c | 427 | |
41e8491f JK |
428 | /* Call check_typedef on our type to make sure that, if TYPE is |
429 | a TYPE_CODE_TYPEDEF, its length is set to the length of the target type | |
430 | instead of zero. However, we do not replace the typedef type by the | |
431 | target type, because we want to keep the typedef in order to be able to | |
432 | set the returned value type description correctly. */ | |
433 | check_typedef (type); | |
c906108c | 434 | |
61212c0f UW |
435 | if (symbol_read_needs_frame (var)) |
436 | gdb_assert (frame); | |
c906108c | 437 | |
24d6c2a0 TT |
438 | if (SYMBOL_COMPUTED_OPS (var) != NULL) |
439 | return SYMBOL_COMPUTED_OPS (var)->read_variable (var, frame); | |
440 | ||
c906108c SS |
441 | switch (SYMBOL_CLASS (var)) |
442 | { | |
443 | case LOC_CONST: | |
444 | /* Put the constant back in target format. */ | |
41e8491f | 445 | v = allocate_value (type); |
744a8059 | 446 | store_signed_integer (value_contents_raw (v), TYPE_LENGTH (type), |
e17a4113 | 447 | gdbarch_byte_order (get_type_arch (type)), |
c906108c SS |
448 | (LONGEST) SYMBOL_VALUE (var)); |
449 | VALUE_LVAL (v) = not_lval; | |
450 | return v; | |
451 | ||
452 | case LOC_LABEL: | |
453 | /* Put the constant back in target format. */ | |
41e8491f | 454 | v = allocate_value (type); |
c906108c | 455 | if (overlay_debugging) |
4478b372 JB |
456 | { |
457 | CORE_ADDR addr | |
458 | = symbol_overlayed_address (SYMBOL_VALUE_ADDRESS (var), | |
e27d198c TT |
459 | SYMBOL_OBJ_SECTION (SYMBOL_OBJFILE (var), |
460 | var)); | |
bb9bcb69 | 461 | |
990a07ab | 462 | store_typed_address (value_contents_raw (v), type, addr); |
4478b372 | 463 | } |
c906108c | 464 | else |
990a07ab | 465 | store_typed_address (value_contents_raw (v), type, |
4478b372 | 466 | SYMBOL_VALUE_ADDRESS (var)); |
c906108c SS |
467 | VALUE_LVAL (v) = not_lval; |
468 | return v; | |
469 | ||
470 | case LOC_CONST_BYTES: | |
41e8491f | 471 | v = allocate_value (type); |
744a8059 SP |
472 | memcpy (value_contents_raw (v), SYMBOL_VALUE_BYTES (var), |
473 | TYPE_LENGTH (type)); | |
bb9bcb69 MS |
474 | VALUE_LVAL (v) = not_lval; |
475 | return v; | |
c906108c SS |
476 | |
477 | case LOC_STATIC: | |
478 | if (overlay_debugging) | |
479 | addr = symbol_overlayed_address (SYMBOL_VALUE_ADDRESS (var), | |
e27d198c TT |
480 | SYMBOL_OBJ_SECTION (SYMBOL_OBJFILE (var), |
481 | var)); | |
c906108c SS |
482 | else |
483 | addr = SYMBOL_VALUE_ADDRESS (var); | |
484 | break; | |
485 | ||
c906108c | 486 | case LOC_ARG: |
da62e633 | 487 | addr = get_frame_args_address (frame); |
c906108c | 488 | if (!addr) |
8afd712c JK |
489 | error (_("Unknown argument list address for `%s'."), |
490 | SYMBOL_PRINT_NAME (var)); | |
c906108c SS |
491 | addr += SYMBOL_VALUE (var); |
492 | break; | |
493 | ||
494 | case LOC_REF_ARG: | |
f76febae AC |
495 | { |
496 | struct value *ref; | |
497 | CORE_ADDR argref; | |
bb9bcb69 | 498 | |
da62e633 | 499 | argref = get_frame_args_address (frame); |
f76febae | 500 | if (!argref) |
8afd712c JK |
501 | error (_("Unknown argument list address for `%s'."), |
502 | SYMBOL_PRINT_NAME (var)); | |
f76febae | 503 | argref += SYMBOL_VALUE (var); |
00a4c844 | 504 | ref = value_at (lookup_pointer_type (type), argref); |
1aa20aa8 | 505 | addr = value_as_address (ref); |
f76febae AC |
506 | break; |
507 | } | |
c906108c SS |
508 | |
509 | case LOC_LOCAL: | |
da62e633 | 510 | addr = get_frame_locals_address (frame); |
c906108c SS |
511 | addr += SYMBOL_VALUE (var); |
512 | break; | |
513 | ||
c906108c | 514 | case LOC_TYPEDEF: |
8afd712c JK |
515 | error (_("Cannot look up value of a typedef `%s'."), |
516 | SYMBOL_PRINT_NAME (var)); | |
c906108c SS |
517 | break; |
518 | ||
519 | case LOC_BLOCK: | |
520 | if (overlay_debugging) | |
41e8491f | 521 | addr = symbol_overlayed_address |
e27d198c TT |
522 | (BLOCK_START (SYMBOL_BLOCK_VALUE (var)), SYMBOL_OBJ_SECTION (SYMBOL_OBJFILE (var), |
523 | var)); | |
c906108c | 524 | else |
41e8491f JK |
525 | addr = BLOCK_START (SYMBOL_BLOCK_VALUE (var)); |
526 | break; | |
c906108c SS |
527 | |
528 | case LOC_REGISTER: | |
c906108c SS |
529 | case LOC_REGPARM_ADDR: |
530 | { | |
768a979c UW |
531 | int regno = SYMBOL_REGISTER_OPS (var) |
532 | ->register_number (var, get_frame_arch (frame)); | |
3d6d86c6 | 533 | struct value *regval; |
c906108c | 534 | |
c906108c SS |
535 | if (SYMBOL_CLASS (var) == LOC_REGPARM_ADDR) |
536 | { | |
537 | regval = value_from_register (lookup_pointer_type (type), | |
c5aa993b | 538 | regno, |
c906108c SS |
539 | frame); |
540 | ||
541 | if (regval == NULL) | |
8afd712c JK |
542 | error (_("Value of register variable not available for `%s'."), |
543 | SYMBOL_PRINT_NAME (var)); | |
c906108c | 544 | |
1aa20aa8 | 545 | addr = value_as_address (regval); |
c906108c SS |
546 | } |
547 | else | |
548 | { | |
549 | regval = value_from_register (type, regno, frame); | |
550 | ||
551 | if (regval == NULL) | |
8afd712c JK |
552 | error (_("Value of register variable not available for `%s'."), |
553 | SYMBOL_PRINT_NAME (var)); | |
c906108c SS |
554 | return regval; |
555 | } | |
556 | } | |
557 | break; | |
558 | ||
4c2df51b | 559 | case LOC_COMPUTED: |
24d6c2a0 | 560 | gdb_assert_not_reached (_("LOC_COMPUTED variable missing a method")); |
4c2df51b | 561 | |
c906108c SS |
562 | case LOC_UNRESOLVED: |
563 | { | |
19630284 | 564 | struct minsym_lookup_data lookup_data; |
c906108c | 565 | struct minimal_symbol *msym; |
e0740f77 | 566 | struct obj_section *obj_section; |
c906108c | 567 | |
19630284 JB |
568 | memset (&lookup_data, 0, sizeof (lookup_data)); |
569 | lookup_data.name = SYMBOL_LINKAGE_NAME (var); | |
570 | ||
571 | gdbarch_iterate_over_objfiles_in_search_order | |
572 | (get_objfile_arch (SYMBOL_SYMTAB (var)->objfile), | |
573 | minsym_lookup_iterator_cb, &lookup_data, | |
574 | SYMBOL_SYMTAB (var)->objfile); | |
575 | msym = lookup_data.result; | |
576 | ||
c906108c | 577 | if (msym == NULL) |
8afd712c | 578 | error (_("No global symbol \"%s\"."), SYMBOL_LINKAGE_NAME (var)); |
c906108c SS |
579 | if (overlay_debugging) |
580 | addr = symbol_overlayed_address (SYMBOL_VALUE_ADDRESS (msym), | |
e27d198c TT |
581 | SYMBOL_OBJ_SECTION (lookup_data.objfile, |
582 | msym)); | |
c906108c SS |
583 | else |
584 | addr = SYMBOL_VALUE_ADDRESS (msym); | |
e0740f77 | 585 | |
e27d198c | 586 | obj_section = SYMBOL_OBJ_SECTION (lookup_data.objfile, msym); |
e0740f77 JK |
587 | if (obj_section |
588 | && (obj_section->the_bfd_section->flags & SEC_THREAD_LOCAL) != 0) | |
589 | addr = target_translate_tls_address (obj_section->objfile, addr); | |
c906108c SS |
590 | } |
591 | break; | |
592 | ||
593 | case LOC_OPTIMIZED_OUT: | |
a7035dbb | 594 | return allocate_optimized_out_value (type); |
c906108c SS |
595 | |
596 | default: | |
8afd712c JK |
597 | error (_("Cannot look up value of a botched symbol `%s'."), |
598 | SYMBOL_PRINT_NAME (var)); | |
c906108c SS |
599 | break; |
600 | } | |
601 | ||
08039c9e | 602 | v = value_at_lazy (type, addr); |
c906108c SS |
603 | return v; |
604 | } | |
605 | ||
a5ee536b JB |
606 | /* Calls VAR's language la_read_var_value hook with the given arguments. */ |
607 | ||
608 | struct value * | |
609 | read_var_value (struct symbol *var, struct frame_info *frame) | |
610 | { | |
611 | const struct language_defn *lang = language_def (SYMBOL_LANGUAGE (var)); | |
612 | ||
613 | gdb_assert (lang != NULL); | |
614 | gdb_assert (lang->la_read_var_value != NULL); | |
615 | ||
616 | return lang->la_read_var_value (var, frame); | |
617 | } | |
618 | ||
9acbedc0 UW |
619 | /* Install default attributes for register values. */ |
620 | ||
621 | struct value * | |
622 | default_value_from_register (struct type *type, int regnum, | |
623 | struct frame_info *frame) | |
624 | { | |
625 | struct gdbarch *gdbarch = get_frame_arch (frame); | |
626 | int len = TYPE_LENGTH (type); | |
627 | struct value *value = allocate_value (type); | |
628 | ||
629 | VALUE_LVAL (value) = lval_register; | |
630 | VALUE_FRAME_ID (value) = get_frame_id (frame); | |
631 | VALUE_REGNUM (value) = regnum; | |
632 | ||
633 | /* Any structure stored in more than one register will always be | |
634 | an integral number of registers. Otherwise, you need to do | |
635 | some fiddling with the last register copied here for little | |
636 | endian machines. */ | |
e9e45075 | 637 | if (gdbarch_byte_order (gdbarch) == BFD_ENDIAN_BIG |
9acbedc0 UW |
638 | && len < register_size (gdbarch, regnum)) |
639 | /* Big-endian, and we want less than full size. */ | |
640 | set_value_offset (value, register_size (gdbarch, regnum) - len); | |
641 | else | |
642 | set_value_offset (value, 0); | |
643 | ||
644 | return value; | |
645 | } | |
646 | ||
b56d6f31 JB |
647 | /* VALUE must be an lval_register value. If regnum is the value's |
648 | associated register number, and len the length of the values type, | |
649 | read one or more registers in FRAME, starting with register REGNUM, | |
2603f7ee AB |
650 | until we've read LEN bytes. |
651 | ||
652 | If any of the registers we try to read are optimized out, then mark the | |
653 | complete resulting value as optimized out. */ | |
b56d6f31 JB |
654 | |
655 | void | |
656 | read_frame_register_value (struct value *value, struct frame_info *frame) | |
657 | { | |
01efb936 | 658 | struct gdbarch *gdbarch = get_frame_arch (frame); |
b56d6f31 | 659 | int offset = 0; |
01efb936 | 660 | int reg_offset = value_offset (value); |
b56d6f31 | 661 | int regnum = VALUE_REGNUM (value); |
01efb936 | 662 | int len = TYPE_LENGTH (check_typedef (value_type (value))); |
b56d6f31 JB |
663 | |
664 | gdb_assert (VALUE_LVAL (value) == lval_register); | |
665 | ||
01efb936 UW |
666 | /* Skip registers wholly inside of REG_OFFSET. */ |
667 | while (reg_offset >= register_size (gdbarch, regnum)) | |
668 | { | |
669 | reg_offset -= register_size (gdbarch, regnum); | |
670 | regnum++; | |
671 | } | |
672 | ||
673 | /* Copy the data. */ | |
674 | while (len > 0) | |
b56d6f31 JB |
675 | { |
676 | struct value *regval = get_frame_register_value (frame, regnum); | |
01efb936 | 677 | int reg_len = TYPE_LENGTH (value_type (regval)) - reg_offset; |
b56d6f31 | 678 | |
2603f7ee AB |
679 | if (value_optimized_out (regval)) |
680 | { | |
681 | set_value_optimized_out (value, 1); | |
682 | break; | |
683 | } | |
684 | ||
22355c90 JB |
685 | /* If the register length is larger than the number of bytes |
686 | remaining to copy, then only copy the appropriate bytes. */ | |
01efb936 UW |
687 | if (reg_len > len) |
688 | reg_len = len; | |
22355c90 | 689 | |
01efb936 | 690 | value_contents_copy (value, offset, regval, reg_offset, reg_len); |
b56d6f31 JB |
691 | |
692 | offset += reg_len; | |
01efb936 UW |
693 | len -= reg_len; |
694 | reg_offset = 0; | |
b56d6f31 JB |
695 | regnum++; |
696 | } | |
697 | } | |
698 | ||
00fa51f6 | 699 | /* Return a value of type TYPE, stored in register REGNUM, in frame FRAME. */ |
c906108c | 700 | |
3d6d86c6 | 701 | struct value * |
fba45db2 | 702 | value_from_register (struct type *type, int regnum, struct frame_info *frame) |
c906108c | 703 | { |
ff2e87ac | 704 | struct gdbarch *gdbarch = get_frame_arch (frame); |
9acbedc0 UW |
705 | struct type *type1 = check_typedef (type); |
706 | struct value *v; | |
707 | ||
e9e45075 | 708 | if (gdbarch_convert_register_p (gdbarch, regnum, type1)) |
ff2e87ac | 709 | { |
3543a589 TT |
710 | int optim, unavail, ok; |
711 | ||
ff2e87ac AC |
712 | /* The ISA/ABI need to something weird when obtaining the |
713 | specified value from this register. It might need to | |
714 | re-order non-adjacent, starting with REGNUM (see MIPS and | |
715 | i386). It might need to convert the [float] register into | |
716 | the corresponding [integer] type (see Alpha). The assumption | |
c1afe53d | 717 | is that gdbarch_register_to_value populates the entire value |
ff2e87ac | 718 | including the location. */ |
9acbedc0 UW |
719 | v = allocate_value (type); |
720 | VALUE_LVAL (v) = lval_register; | |
721 | VALUE_FRAME_ID (v) = get_frame_id (frame); | |
722 | VALUE_REGNUM (v) = regnum; | |
8dccd430 PA |
723 | ok = gdbarch_register_to_value (gdbarch, frame, regnum, type1, |
724 | value_contents_raw (v), &optim, | |
725 | &unavail); | |
3543a589 TT |
726 | |
727 | if (!ok) | |
728 | { | |
729 | if (optim) | |
730 | set_value_optimized_out (v, 1); | |
731 | if (unavail) | |
732 | mark_value_bytes_unavailable (v, 0, TYPE_LENGTH (type)); | |
733 | } | |
ff2e87ac AC |
734 | } |
735 | else | |
c906108c | 736 | { |
9acbedc0 UW |
737 | /* Construct the value. */ |
738 | v = gdbarch_value_from_register (gdbarch, type, regnum, frame); | |
00fa51f6 UW |
739 | |
740 | /* Get the data. */ | |
b56d6f31 | 741 | read_frame_register_value (v, frame); |
c906108c | 742 | } |
8dccd430 | 743 | |
c906108c SS |
744 | return v; |
745 | } | |
ff2e87ac | 746 | |
0b2b0195 UW |
747 | /* Return contents of register REGNUM in frame FRAME as address, |
748 | interpreted as value of type TYPE. Will abort if register | |
749 | value is not available. */ | |
750 | ||
751 | CORE_ADDR | |
752 | address_from_register (struct type *type, int regnum, struct frame_info *frame) | |
753 | { | |
754 | struct value *value; | |
755 | CORE_ADDR result; | |
756 | ||
757 | value = value_from_register (type, regnum, frame); | |
758 | gdb_assert (value); | |
759 | ||
901461f8 PA |
760 | if (value_optimized_out (value)) |
761 | { | |
762 | /* This function is used while computing a location expression. | |
763 | Complain about the value being optimized out, rather than | |
764 | letting value_as_address complain about some random register | |
765 | the expression depends on not being saved. */ | |
766 | error_value_optimized_out (); | |
767 | } | |
768 | ||
0b2b0195 UW |
769 | result = value_as_address (value); |
770 | release_value (value); | |
771 | value_free (value); | |
772 | ||
773 | return result; | |
774 | } | |
b56d6f31 | 775 |