Commit | Line | Data |
---|---|---|
c906108c | 1 | /* Find a variable's value in memory, for GDB, the GNU debugger. |
1bac305b | 2 | |
6aba47ca DJ |
3 | Copyright (C) 1986, 1987, 1988, 1989, 1990, 1991, 1992, 1993, 1994, 1995, |
4 | 1996, 1997, 1998, 1999, 2000, 2001, 2003, 2004, 2005, 2007 | |
5 | Free Software Foundation, Inc. | |
c906108c | 6 | |
c5aa993b | 7 | This file is part of GDB. |
c906108c | 8 | |
c5aa993b JM |
9 | This program is free software; you can redistribute it and/or modify |
10 | it under the terms of the GNU General Public License as published by | |
11 | the Free Software Foundation; either version 2 of the License, or | |
12 | (at your option) any later version. | |
c906108c | 13 | |
c5aa993b JM |
14 | This program is distributed in the hope that it will be useful, |
15 | but WITHOUT ANY WARRANTY; without even the implied warranty of | |
16 | MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the | |
17 | GNU General Public License for more details. | |
c906108c | 18 | |
c5aa993b JM |
19 | You should have received a copy of the GNU General Public License |
20 | along with this program; if not, write to the Free Software | |
197e01b6 EZ |
21 | Foundation, Inc., 51 Franklin Street, Fifth Floor, |
22 | Boston, MA 02110-1301, USA. */ | |
c906108c SS |
23 | |
24 | #include "defs.h" | |
25 | #include "symtab.h" | |
26 | #include "gdbtypes.h" | |
27 | #include "frame.h" | |
28 | #include "value.h" | |
29 | #include "gdbcore.h" | |
30 | #include "inferior.h" | |
31 | #include "target.h" | |
32 | #include "gdb_string.h" | |
14e534aa | 33 | #include "gdb_assert.h" |
c906108c | 34 | #include "floatformat.h" |
c5aa993b | 35 | #include "symfile.h" /* for overlay functions */ |
4e052eda | 36 | #include "regcache.h" |
eb8bc282 | 37 | #include "user-regs.h" |
fe898f56 | 38 | #include "block.h" |
c906108c | 39 | |
c906108c SS |
40 | /* Basic byte-swapping routines. GDB has needed these for a long time... |
41 | All extract a target-format integer at ADDR which is LEN bytes long. */ | |
42 | ||
43 | #if TARGET_CHAR_BIT != 8 || HOST_CHAR_BIT != 8 | |
44 | /* 8 bit characters are a pretty safe assumption these days, so we | |
45 | assume it throughout all these swapping routines. If we had to deal with | |
46 | 9 bit characters, we would need to make len be in bits and would have | |
47 | to re-write these routines... */ | |
c5aa993b | 48 | you lose |
c906108c SS |
49 | #endif |
50 | ||
a9ac8f51 | 51 | LONGEST |
0d509538 | 52 | extract_signed_integer (const gdb_byte *addr, int len) |
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. */ | |
d7449b42 | 66 | if (TARGET_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 | |
0d509538 | 86 | extract_unsigned_integer (const gdb_byte *addr, int len) |
c906108c SS |
87 | { |
88 | ULONGEST retval; | |
37611a2b AC |
89 | const unsigned char *p; |
90 | const unsigned char *startaddr = addr; | |
91 | const unsigned char *endaddr = startaddr + len; | |
c906108c SS |
92 | |
93 | if (len > (int) sizeof (ULONGEST)) | |
8a3fe4f8 AC |
94 | error (_("\ |
95 | That operation is not available on integers of more than %d bytes."), | |
baa6f10b | 96 | (int) sizeof (ULONGEST)); |
c906108c SS |
97 | |
98 | /* Start at the most significant end of the integer, and work towards | |
99 | the least significant. */ | |
100 | retval = 0; | |
d7449b42 | 101 | if (TARGET_BYTE_ORDER == BFD_ENDIAN_BIG) |
c906108c SS |
102 | { |
103 | for (p = startaddr; p < endaddr; ++p) | |
104 | retval = (retval << 8) | *p; | |
105 | } | |
106 | else | |
107 | { | |
108 | for (p = endaddr - 1; p >= startaddr; --p) | |
109 | retval = (retval << 8) | *p; | |
110 | } | |
111 | return retval; | |
112 | } | |
113 | ||
114 | /* Sometimes a long long unsigned integer can be extracted as a | |
115 | LONGEST value. This is done so that we can print these values | |
116 | better. If this integer can be converted to a LONGEST, this | |
117 | function returns 1 and sets *PVAL. Otherwise it returns 0. */ | |
118 | ||
119 | int | |
0d509538 AC |
120 | extract_long_unsigned_integer (const gdb_byte *addr, int orig_len, |
121 | LONGEST *pval) | |
c906108c | 122 | { |
0d509538 AC |
123 | const gdb_byte *p; |
124 | const gdb_byte *first_addr; | |
c906108c SS |
125 | int len; |
126 | ||
127 | len = orig_len; | |
d7449b42 | 128 | if (TARGET_BYTE_ORDER == BFD_ENDIAN_BIG) |
c906108c | 129 | { |
0d509538 AC |
130 | for (p = addr; |
131 | len > (int) sizeof (LONGEST) && p < addr + orig_len; | |
c906108c SS |
132 | p++) |
133 | { | |
134 | if (*p == 0) | |
135 | len--; | |
136 | else | |
137 | break; | |
138 | } | |
139 | first_addr = p; | |
140 | } | |
141 | else | |
142 | { | |
0d509538 AC |
143 | first_addr = addr; |
144 | for (p = addr + orig_len - 1; | |
145 | len > (int) sizeof (LONGEST) && p >= addr; | |
c906108c SS |
146 | p--) |
147 | { | |
148 | if (*p == 0) | |
149 | len--; | |
150 | else | |
151 | break; | |
152 | } | |
153 | } | |
154 | ||
155 | if (len <= (int) sizeof (LONGEST)) | |
156 | { | |
157 | *pval = (LONGEST) extract_unsigned_integer (first_addr, | |
158 | sizeof (LONGEST)); | |
159 | return 1; | |
160 | } | |
161 | ||
162 | return 0; | |
163 | } | |
164 | ||
4478b372 | 165 | |
4478b372 JB |
166 | /* Treat the bytes at BUF as a pointer of type TYPE, and return the |
167 | address it represents. */ | |
168 | CORE_ADDR | |
0d509538 | 169 | extract_typed_address (const gdb_byte *buf, struct type *type) |
4478b372 JB |
170 | { |
171 | if (TYPE_CODE (type) != TYPE_CODE_PTR | |
172 | && TYPE_CODE (type) != TYPE_CODE_REF) | |
8e65ff28 | 173 | internal_error (__FILE__, __LINE__, |
e2e0b3e5 AC |
174 | _("extract_typed_address: " |
175 | "type is not a pointer or reference")); | |
4478b372 JB |
176 | |
177 | return POINTER_TO_ADDRESS (type, buf); | |
178 | } | |
179 | ||
180 | ||
c906108c | 181 | void |
0d509538 | 182 | store_signed_integer (gdb_byte *addr, int len, LONGEST val) |
c906108c | 183 | { |
0d509538 AC |
184 | gdb_byte *p; |
185 | gdb_byte *startaddr = addr; | |
186 | gdb_byte *endaddr = startaddr + len; | |
c906108c SS |
187 | |
188 | /* Start at the least significant end of the integer, and work towards | |
189 | the most significant. */ | |
d7449b42 | 190 | if (TARGET_BYTE_ORDER == BFD_ENDIAN_BIG) |
c906108c SS |
191 | { |
192 | for (p = endaddr - 1; p >= startaddr; --p) | |
193 | { | |
194 | *p = val & 0xff; | |
195 | val >>= 8; | |
196 | } | |
197 | } | |
198 | else | |
199 | { | |
200 | for (p = startaddr; p < endaddr; ++p) | |
201 | { | |
202 | *p = val & 0xff; | |
203 | val >>= 8; | |
204 | } | |
205 | } | |
206 | } | |
207 | ||
208 | void | |
0d509538 | 209 | store_unsigned_integer (gdb_byte *addr, int len, ULONGEST val) |
c906108c SS |
210 | { |
211 | unsigned char *p; | |
c5aa993b | 212 | unsigned char *startaddr = (unsigned char *) addr; |
c906108c SS |
213 | unsigned char *endaddr = startaddr + len; |
214 | ||
215 | /* Start at the least significant end of the integer, and work towards | |
216 | the most significant. */ | |
d7449b42 | 217 | if (TARGET_BYTE_ORDER == BFD_ENDIAN_BIG) |
c906108c SS |
218 | { |
219 | for (p = endaddr - 1; p >= startaddr; --p) | |
220 | { | |
221 | *p = val & 0xff; | |
222 | val >>= 8; | |
223 | } | |
224 | } | |
225 | else | |
226 | { | |
227 | for (p = startaddr; p < endaddr; ++p) | |
228 | { | |
229 | *p = val & 0xff; | |
230 | val >>= 8; | |
231 | } | |
232 | } | |
233 | } | |
234 | ||
4478b372 JB |
235 | /* Store the address ADDR as a pointer of type TYPE at BUF, in target |
236 | form. */ | |
237 | void | |
0d509538 | 238 | store_typed_address (gdb_byte *buf, struct type *type, CORE_ADDR addr) |
4478b372 JB |
239 | { |
240 | if (TYPE_CODE (type) != TYPE_CODE_PTR | |
241 | && TYPE_CODE (type) != TYPE_CODE_REF) | |
8e65ff28 | 242 | internal_error (__FILE__, __LINE__, |
e2e0b3e5 AC |
243 | _("store_typed_address: " |
244 | "type is not a pointer or reference")); | |
4478b372 JB |
245 | |
246 | ADDRESS_TO_POINTER (type, buf, addr); | |
247 | } | |
248 | ||
249 | ||
250 | ||
376c9600 AC |
251 | /* Return a `value' with the contents of (virtual or cooked) register |
252 | REGNUM as found in the specified FRAME. The register's type is | |
9c5ea4d9 | 253 | determined by register_type(). */ |
c906108c | 254 | |
3d6d86c6 | 255 | struct value * |
376c9600 | 256 | value_of_register (int regnum, struct frame_info *frame) |
c906108c SS |
257 | { |
258 | CORE_ADDR addr; | |
259 | int optim; | |
3d6d86c6 | 260 | struct value *reg_val; |
ac2adee5 | 261 | int realnum; |
10c42a71 | 262 | gdb_byte raw_buffer[MAX_REGISTER_SIZE]; |
c906108c SS |
263 | enum lval_type lval; |
264 | ||
9564ee9f | 265 | /* User registers lie completely outside of the range of normal |
0406ec40 AC |
266 | registers. Catch them early so that the target never sees them. */ |
267 | if (regnum >= NUM_REGS + NUM_PSEUDO_REGS) | |
eb8bc282 | 268 | return value_of_user_reg (regnum, frame); |
0406ec40 | 269 | |
ac2adee5 | 270 | frame_register (frame, regnum, &optim, &lval, &addr, &realnum, raw_buffer); |
c906108c | 271 | |
7b83296f | 272 | reg_val = allocate_value (register_type (current_gdbarch, regnum)); |
c906108c | 273 | |
990a07ab | 274 | memcpy (value_contents_raw (reg_val), raw_buffer, |
01e1877c | 275 | register_size (current_gdbarch, regnum)); |
c906108c SS |
276 | VALUE_LVAL (reg_val) = lval; |
277 | VALUE_ADDRESS (reg_val) = addr; | |
9ee8fc9d | 278 | VALUE_REGNUM (reg_val) = regnum; |
feb13ab0 | 279 | set_value_optimized_out (reg_val, optim); |
0c16dd26 | 280 | VALUE_FRAME_ID (reg_val) = get_frame_id (frame); |
c906108c SS |
281 | return reg_val; |
282 | } | |
4478b372 JB |
283 | |
284 | /* Given a pointer of type TYPE in target form in BUF, return the | |
285 | address it represents. */ | |
286 | CORE_ADDR | |
b60c417a | 287 | unsigned_pointer_to_address (struct type *type, const gdb_byte *buf) |
4478b372 | 288 | { |
af1342ab | 289 | return extract_unsigned_integer (buf, TYPE_LENGTH (type)); |
4478b372 JB |
290 | } |
291 | ||
ac2e2ef7 | 292 | CORE_ADDR |
b60c417a | 293 | signed_pointer_to_address (struct type *type, const gdb_byte *buf) |
ac2e2ef7 AC |
294 | { |
295 | return extract_signed_integer (buf, TYPE_LENGTH (type)); | |
296 | } | |
4478b372 JB |
297 | |
298 | /* Given an address, store it as a pointer of type TYPE in target | |
299 | format in BUF. */ | |
300 | void | |
b60c417a AC |
301 | unsigned_address_to_pointer (struct type *type, gdb_byte *buf, |
302 | CORE_ADDR addr) | |
4478b372 | 303 | { |
fbd9dcd3 | 304 | store_unsigned_integer (buf, TYPE_LENGTH (type), addr); |
4478b372 JB |
305 | } |
306 | ||
ac2e2ef7 | 307 | void |
b60c417a | 308 | address_to_signed_pointer (struct type *type, gdb_byte *buf, CORE_ADDR addr) |
ac2e2ef7 AC |
309 | { |
310 | store_signed_integer (buf, TYPE_LENGTH (type), addr); | |
311 | } | |
c906108c SS |
312 | \f |
313 | /* Will calling read_var_value or locate_var_value on SYM end | |
314 | up caring what frame it is being evaluated relative to? SYM must | |
315 | be non-NULL. */ | |
316 | int | |
fba45db2 | 317 | symbol_read_needs_frame (struct symbol *sym) |
c906108c SS |
318 | { |
319 | switch (SYMBOL_CLASS (sym)) | |
320 | { | |
321 | /* All cases listed explicitly so that gcc -Wall will detect it if | |
c5aa993b | 322 | we failed to consider one. */ |
4c2df51b DJ |
323 | case LOC_COMPUTED: |
324 | case LOC_COMPUTED_ARG: | |
a67af2b9 AC |
325 | /* FIXME: cagney/2004-01-26: It should be possible to |
326 | unconditionally call the SYMBOL_OPS method when available. | |
d3efc286 | 327 | Unfortunately DWARF 2 stores the frame-base (instead of the |
a67af2b9 AC |
328 | function) location in a function's symbol. Oops! For the |
329 | moment enable this when/where applicable. */ | |
330 | return SYMBOL_OPS (sym)->read_needs_frame (sym); | |
4c2df51b | 331 | |
c906108c SS |
332 | case LOC_REGISTER: |
333 | case LOC_ARG: | |
334 | case LOC_REF_ARG: | |
335 | case LOC_REGPARM: | |
336 | case LOC_REGPARM_ADDR: | |
337 | case LOC_LOCAL: | |
338 | case LOC_LOCAL_ARG: | |
339 | case LOC_BASEREG: | |
340 | case LOC_BASEREG_ARG: | |
407caf07 | 341 | case LOC_HP_THREAD_LOCAL_STATIC: |
c906108c SS |
342 | return 1; |
343 | ||
344 | case LOC_UNDEF: | |
345 | case LOC_CONST: | |
346 | case LOC_STATIC: | |
347 | case LOC_INDIRECT: | |
348 | case LOC_TYPEDEF: | |
349 | ||
350 | case LOC_LABEL: | |
351 | /* Getting the address of a label can be done independently of the block, | |
c5aa993b JM |
352 | even if some *uses* of that address wouldn't work so well without |
353 | the right frame. */ | |
c906108c SS |
354 | |
355 | case LOC_BLOCK: | |
356 | case LOC_CONST_BYTES: | |
357 | case LOC_UNRESOLVED: | |
358 | case LOC_OPTIMIZED_OUT: | |
359 | return 0; | |
360 | } | |
361 | return 1; | |
362 | } | |
363 | ||
364 | /* Given a struct symbol for a variable, | |
365 | and a stack frame id, read the value of the variable | |
366 | and return a (pointer to a) struct value containing the value. | |
367 | If the variable cannot be found, return a zero pointer. | |
206415a3 | 368 | If FRAME is NULL, use the selected frame. */ |
c906108c | 369 | |
3d6d86c6 | 370 | struct value * |
aa1ee363 | 371 | read_var_value (struct symbol *var, struct frame_info *frame) |
c906108c | 372 | { |
52f0bd74 | 373 | struct value *v; |
c906108c SS |
374 | struct type *type = SYMBOL_TYPE (var); |
375 | CORE_ADDR addr; | |
52f0bd74 | 376 | int len; |
c906108c | 377 | |
bb044262 DJ |
378 | if (SYMBOL_CLASS (var) == LOC_COMPUTED |
379 | || SYMBOL_CLASS (var) == LOC_COMPUTED_ARG | |
380 | || SYMBOL_CLASS (var) == LOC_REGISTER | |
381 | || SYMBOL_CLASS (var) == LOC_REGPARM) | |
382 | /* These cases do not use V. */ | |
383 | v = NULL; | |
384 | else | |
385 | { | |
386 | v = allocate_value (type); | |
387 | VALUE_LVAL (v) = lval_memory; /* The most likely possibility. */ | |
388 | } | |
c906108c SS |
389 | |
390 | len = TYPE_LENGTH (type); | |
391 | ||
7dd88986 DJ |
392 | /* FIXME drow/2003-09-06: this call to the selected frame should be |
393 | pushed upwards to the callers. */ | |
c5aa993b | 394 | if (frame == NULL) |
7dd88986 | 395 | frame = deprecated_safe_get_selected_frame (); |
c906108c SS |
396 | |
397 | switch (SYMBOL_CLASS (var)) | |
398 | { | |
399 | case LOC_CONST: | |
400 | /* Put the constant back in target format. */ | |
990a07ab | 401 | store_signed_integer (value_contents_raw (v), len, |
c906108c SS |
402 | (LONGEST) SYMBOL_VALUE (var)); |
403 | VALUE_LVAL (v) = not_lval; | |
404 | return v; | |
405 | ||
406 | case LOC_LABEL: | |
407 | /* Put the constant back in target format. */ | |
408 | if (overlay_debugging) | |
4478b372 JB |
409 | { |
410 | CORE_ADDR addr | |
411 | = symbol_overlayed_address (SYMBOL_VALUE_ADDRESS (var), | |
412 | SYMBOL_BFD_SECTION (var)); | |
990a07ab | 413 | store_typed_address (value_contents_raw (v), type, addr); |
4478b372 | 414 | } |
c906108c | 415 | else |
990a07ab | 416 | store_typed_address (value_contents_raw (v), type, |
4478b372 | 417 | SYMBOL_VALUE_ADDRESS (var)); |
c906108c SS |
418 | VALUE_LVAL (v) = not_lval; |
419 | return v; | |
420 | ||
421 | case LOC_CONST_BYTES: | |
422 | { | |
4e38b386 | 423 | memcpy (value_contents_raw (v), SYMBOL_VALUE_BYTES (var), len); |
c906108c SS |
424 | VALUE_LVAL (v) = not_lval; |
425 | return v; | |
426 | } | |
427 | ||
428 | case LOC_STATIC: | |
429 | if (overlay_debugging) | |
430 | addr = symbol_overlayed_address (SYMBOL_VALUE_ADDRESS (var), | |
431 | SYMBOL_BFD_SECTION (var)); | |
432 | else | |
433 | addr = SYMBOL_VALUE_ADDRESS (var); | |
434 | break; | |
435 | ||
436 | case LOC_INDIRECT: | |
f76febae AC |
437 | { |
438 | /* The import slot does not have a real address in it from the | |
439 | dynamic loader (dld.sl on HP-UX), if the target hasn't | |
440 | begun execution yet, so check for that. */ | |
441 | CORE_ADDR locaddr; | |
442 | struct value *loc; | |
443 | if (!target_has_execution) | |
8a3fe4f8 | 444 | error (_("\ |
c906108c | 445 | Attempt to access variable defined in different shared object or load module when\n\ |
8a3fe4f8 | 446 | addresses have not been bound by the dynamic loader. Try again when executable is running.")); |
c5aa993b | 447 | |
f76febae | 448 | locaddr = SYMBOL_VALUE_ADDRESS (var); |
00a4c844 | 449 | loc = value_at (lookup_pointer_type (type), locaddr); |
1aa20aa8 | 450 | addr = value_as_address (loc); |
bb044262 | 451 | break; |
f76febae | 452 | } |
c906108c SS |
453 | |
454 | case LOC_ARG: | |
455 | if (frame == NULL) | |
456 | return 0; | |
da62e633 | 457 | addr = get_frame_args_address (frame); |
c906108c SS |
458 | if (!addr) |
459 | return 0; | |
460 | addr += SYMBOL_VALUE (var); | |
461 | break; | |
462 | ||
463 | case LOC_REF_ARG: | |
f76febae AC |
464 | { |
465 | struct value *ref; | |
466 | CORE_ADDR argref; | |
467 | if (frame == NULL) | |
468 | return 0; | |
da62e633 | 469 | argref = get_frame_args_address (frame); |
f76febae AC |
470 | if (!argref) |
471 | return 0; | |
472 | argref += SYMBOL_VALUE (var); | |
00a4c844 | 473 | ref = value_at (lookup_pointer_type (type), argref); |
1aa20aa8 | 474 | addr = value_as_address (ref); |
f76febae AC |
475 | break; |
476 | } | |
c906108c SS |
477 | |
478 | case LOC_LOCAL: | |
479 | case LOC_LOCAL_ARG: | |
480 | if (frame == NULL) | |
481 | return 0; | |
da62e633 | 482 | addr = get_frame_locals_address (frame); |
c906108c SS |
483 | addr += SYMBOL_VALUE (var); |
484 | break; | |
485 | ||
486 | case LOC_BASEREG: | |
487 | case LOC_BASEREG_ARG: | |
407caf07 | 488 | case LOC_HP_THREAD_LOCAL_STATIC: |
c906108c | 489 | { |
3d6d86c6 | 490 | struct value *regval; |
c5aa993b | 491 | |
9ed10b08 ND |
492 | regval = value_from_register (lookup_pointer_type (type), |
493 | SYMBOL_BASEREG (var), frame); | |
494 | if (regval == NULL) | |
8a3fe4f8 | 495 | error (_("Value of base register not available.")); |
1aa20aa8 | 496 | addr = value_as_address (regval); |
c5aa993b JM |
497 | addr += SYMBOL_VALUE (var); |
498 | break; | |
c906108c | 499 | } |
c5aa993b | 500 | |
c906108c | 501 | case LOC_TYPEDEF: |
8a3fe4f8 | 502 | error (_("Cannot look up value of a typedef")); |
c906108c SS |
503 | break; |
504 | ||
505 | case LOC_BLOCK: | |
506 | if (overlay_debugging) | |
c5aa993b | 507 | VALUE_ADDRESS (v) = symbol_overlayed_address |
c906108c SS |
508 | (BLOCK_START (SYMBOL_BLOCK_VALUE (var)), SYMBOL_BFD_SECTION (var)); |
509 | else | |
510 | VALUE_ADDRESS (v) = BLOCK_START (SYMBOL_BLOCK_VALUE (var)); | |
511 | return v; | |
512 | ||
513 | case LOC_REGISTER: | |
514 | case LOC_REGPARM: | |
515 | case LOC_REGPARM_ADDR: | |
516 | { | |
517 | struct block *b; | |
518 | int regno = SYMBOL_VALUE (var); | |
3d6d86c6 | 519 | struct value *regval; |
c906108c SS |
520 | |
521 | if (frame == NULL) | |
522 | return 0; | |
ae767bfb | 523 | b = get_frame_block (frame, 0); |
c906108c SS |
524 | |
525 | if (SYMBOL_CLASS (var) == LOC_REGPARM_ADDR) | |
526 | { | |
527 | regval = value_from_register (lookup_pointer_type (type), | |
c5aa993b | 528 | regno, |
c906108c SS |
529 | frame); |
530 | ||
531 | if (regval == NULL) | |
8a3fe4f8 | 532 | error (_("Value of register variable not available.")); |
c906108c | 533 | |
1aa20aa8 | 534 | addr = value_as_address (regval); |
c906108c SS |
535 | VALUE_LVAL (v) = lval_memory; |
536 | } | |
537 | else | |
538 | { | |
539 | regval = value_from_register (type, regno, frame); | |
540 | ||
541 | if (regval == NULL) | |
8a3fe4f8 | 542 | error (_("Value of register variable not available.")); |
c906108c SS |
543 | return regval; |
544 | } | |
545 | } | |
546 | break; | |
547 | ||
4c2df51b DJ |
548 | case LOC_COMPUTED: |
549 | case LOC_COMPUTED_ARG: | |
a67af2b9 AC |
550 | /* FIXME: cagney/2004-01-26: It should be possible to |
551 | unconditionally call the SYMBOL_OPS method when available. | |
d3efc286 | 552 | Unfortunately DWARF 2 stores the frame-base (instead of the |
a67af2b9 AC |
553 | function) location in a function's symbol. Oops! For the |
554 | moment enable this when/where applicable. */ | |
555 | if (frame == 0 && SYMBOL_OPS (var)->read_needs_frame (var)) | |
556 | return 0; | |
557 | return SYMBOL_OPS (var)->read_variable (var, frame); | |
4c2df51b | 558 | |
c906108c SS |
559 | case LOC_UNRESOLVED: |
560 | { | |
561 | struct minimal_symbol *msym; | |
562 | ||
22abf04a | 563 | msym = lookup_minimal_symbol (DEPRECATED_SYMBOL_NAME (var), NULL, NULL); |
c906108c SS |
564 | if (msym == NULL) |
565 | return 0; | |
566 | if (overlay_debugging) | |
567 | addr = symbol_overlayed_address (SYMBOL_VALUE_ADDRESS (msym), | |
568 | SYMBOL_BFD_SECTION (msym)); | |
569 | else | |
570 | addr = SYMBOL_VALUE_ADDRESS (msym); | |
571 | } | |
572 | break; | |
573 | ||
574 | case LOC_OPTIMIZED_OUT: | |
575 | VALUE_LVAL (v) = not_lval; | |
feb13ab0 | 576 | set_value_optimized_out (v, 1); |
c906108c SS |
577 | return v; |
578 | ||
579 | default: | |
8a3fe4f8 | 580 | error (_("Cannot look up value of a botched symbol.")); |
c906108c SS |
581 | break; |
582 | } | |
583 | ||
584 | VALUE_ADDRESS (v) = addr; | |
dfa52d88 | 585 | set_value_lazy (v, 1); |
c906108c SS |
586 | return v; |
587 | } | |
588 | ||
9acbedc0 UW |
589 | /* Install default attributes for register values. */ |
590 | ||
591 | struct value * | |
592 | default_value_from_register (struct type *type, int regnum, | |
593 | struct frame_info *frame) | |
594 | { | |
595 | struct gdbarch *gdbarch = get_frame_arch (frame); | |
596 | int len = TYPE_LENGTH (type); | |
597 | struct value *value = allocate_value (type); | |
598 | ||
599 | VALUE_LVAL (value) = lval_register; | |
600 | VALUE_FRAME_ID (value) = get_frame_id (frame); | |
601 | VALUE_REGNUM (value) = regnum; | |
602 | ||
603 | /* Any structure stored in more than one register will always be | |
604 | an integral number of registers. Otherwise, you need to do | |
605 | some fiddling with the last register copied here for little | |
606 | endian machines. */ | |
607 | if (TARGET_BYTE_ORDER == BFD_ENDIAN_BIG | |
608 | && len < register_size (gdbarch, regnum)) | |
609 | /* Big-endian, and we want less than full size. */ | |
610 | set_value_offset (value, register_size (gdbarch, regnum) - len); | |
611 | else | |
612 | set_value_offset (value, 0); | |
613 | ||
614 | return value; | |
615 | } | |
616 | ||
00fa51f6 | 617 | /* Return a value of type TYPE, stored in register REGNUM, in frame FRAME. */ |
c906108c | 618 | |
3d6d86c6 | 619 | struct value * |
fba45db2 | 620 | value_from_register (struct type *type, int regnum, struct frame_info *frame) |
c906108c | 621 | { |
ff2e87ac | 622 | struct gdbarch *gdbarch = get_frame_arch (frame); |
9acbedc0 UW |
623 | struct type *type1 = check_typedef (type); |
624 | struct value *v; | |
625 | ||
626 | if (CONVERT_REGISTER_P (regnum, type1)) | |
ff2e87ac AC |
627 | { |
628 | /* The ISA/ABI need to something weird when obtaining the | |
629 | specified value from this register. It might need to | |
630 | re-order non-adjacent, starting with REGNUM (see MIPS and | |
631 | i386). It might need to convert the [float] register into | |
632 | the corresponding [integer] type (see Alpha). The assumption | |
633 | is that REGISTER_TO_VALUE populates the entire value | |
634 | including the location. */ | |
9acbedc0 UW |
635 | v = allocate_value (type); |
636 | VALUE_LVAL (v) = lval_register; | |
637 | VALUE_FRAME_ID (v) = get_frame_id (frame); | |
638 | VALUE_REGNUM (v) = regnum; | |
639 | REGISTER_TO_VALUE (frame, regnum, type1, value_contents_raw (v)); | |
ff2e87ac AC |
640 | } |
641 | else | |
c906108c | 642 | { |
ff2e87ac | 643 | int len = TYPE_LENGTH (type); |
00fa51f6 | 644 | |
9acbedc0 UW |
645 | /* Construct the value. */ |
646 | v = gdbarch_value_from_register (gdbarch, type, regnum, frame); | |
00fa51f6 UW |
647 | |
648 | /* Get the data. */ | |
649 | if (!get_frame_register_bytes (frame, regnum, value_offset (v), len, | |
650 | value_contents_raw (v))) | |
651 | set_value_optimized_out (v, 1); | |
c906108c | 652 | } |
c906108c SS |
653 | return v; |
654 | } | |
ff2e87ac | 655 | |
0b2b0195 UW |
656 | /* Return contents of register REGNUM in frame FRAME as address, |
657 | interpreted as value of type TYPE. Will abort if register | |
658 | value is not available. */ | |
659 | ||
660 | CORE_ADDR | |
661 | address_from_register (struct type *type, int regnum, struct frame_info *frame) | |
662 | { | |
663 | struct value *value; | |
664 | CORE_ADDR result; | |
665 | ||
666 | value = value_from_register (type, regnum, frame); | |
667 | gdb_assert (value); | |
668 | ||
669 | result = value_as_address (value); | |
670 | release_value (value); | |
671 | value_free (value); | |
672 | ||
673 | return result; | |
674 | } | |
675 | ||
c906108c SS |
676 | \f |
677 | /* Given a struct symbol for a variable or function, | |
678 | and a stack frame id, | |
679 | return a (pointer to a) struct value containing the properly typed | |
680 | address. */ | |
681 | ||
3d6d86c6 | 682 | struct value * |
aa1ee363 | 683 | locate_var_value (struct symbol *var, struct frame_info *frame) |
c906108c SS |
684 | { |
685 | CORE_ADDR addr = 0; | |
686 | struct type *type = SYMBOL_TYPE (var); | |
3d6d86c6 | 687 | struct value *lazy_value; |
c906108c SS |
688 | |
689 | /* Evaluate it first; if the result is a memory address, we're fine. | |
690 | Lazy evaluation pays off here. */ | |
691 | ||
692 | lazy_value = read_var_value (var, frame); | |
693 | if (lazy_value == 0) | |
8a3fe4f8 | 694 | error (_("Address of \"%s\" is unknown."), SYMBOL_PRINT_NAME (var)); |
c906108c | 695 | |
d69fe07e | 696 | if (value_lazy (lazy_value) |
c906108c SS |
697 | || TYPE_CODE (type) == TYPE_CODE_FUNC) |
698 | { | |
3d6d86c6 | 699 | struct value *val; |
c906108c SS |
700 | |
701 | addr = VALUE_ADDRESS (lazy_value); | |
4478b372 | 702 | val = value_from_pointer (lookup_pointer_type (type), addr); |
c906108c SS |
703 | return val; |
704 | } | |
705 | ||
706 | /* Not a memory address; check what the problem was. */ | |
c5aa993b | 707 | switch (VALUE_LVAL (lazy_value)) |
c906108c SS |
708 | { |
709 | case lval_register: | |
9ee8fc9d AC |
710 | gdb_assert (REGISTER_NAME (VALUE_REGNUM (lazy_value)) != NULL |
711 | && *REGISTER_NAME (VALUE_REGNUM (lazy_value)) != '\0'); | |
8a3fe4f8 AC |
712 | error (_("Address requested for identifier " |
713 | "\"%s\" which is in register $%s"), | |
de5ad195 | 714 | SYMBOL_PRINT_NAME (var), |
9ee8fc9d | 715 | REGISTER_NAME (VALUE_REGNUM (lazy_value))); |
14e534aa PM |
716 | break; |
717 | ||
c906108c | 718 | default: |
8a3fe4f8 | 719 | error (_("Can't take address of \"%s\" which isn't an lvalue."), |
de5ad195 | 720 | SYMBOL_PRINT_NAME (var)); |
c906108c SS |
721 | break; |
722 | } | |
c5aa993b | 723 | return 0; /* For lint -- never reached */ |
c906108c | 724 | } |