Commit | Line | Data |
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c906108c | 1 | /* Find a variable's value in memory, for GDB, the GNU debugger. |
1bac305b | 2 | |
6aba47ca | 3 | Copyright (C) 1986, 1987, 1988, 1989, 1990, 1991, 1992, 1993, 1994, 1995, |
0fb0cc75 | 4 | 1996, 1997, 1998, 1999, 2000, 2001, 2003, 2004, 2005, 2007, 2008, 2009 |
6aba47ca | 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 | |
a9762ec7 | 11 | the Free Software Foundation; either version 3 of the License, or |
c5aa993b | 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 | 19 | You should have received a copy of the GNU General Public License |
a9762ec7 | 20 | along with this program. If not, see <http://www.gnu.org/licenses/>. */ |
c906108c SS |
21 | |
22 | #include "defs.h" | |
23 | #include "symtab.h" | |
24 | #include "gdbtypes.h" | |
25 | #include "frame.h" | |
26 | #include "value.h" | |
27 | #include "gdbcore.h" | |
28 | #include "inferior.h" | |
29 | #include "target.h" | |
30 | #include "gdb_string.h" | |
14e534aa | 31 | #include "gdb_assert.h" |
c906108c | 32 | #include "floatformat.h" |
c5aa993b | 33 | #include "symfile.h" /* for overlay functions */ |
4e052eda | 34 | #include "regcache.h" |
eb8bc282 | 35 | #include "user-regs.h" |
fe898f56 | 36 | #include "block.h" |
e0740f77 | 37 | #include "objfiles.h" |
c906108c | 38 | |
c906108c SS |
39 | /* Basic byte-swapping routines. GDB has needed these for a long time... |
40 | All extract a target-format integer at ADDR which is LEN bytes long. */ | |
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 |
0d509538 | 51 | extract_signed_integer (const gdb_byte *addr, int len) |
c906108c SS |
52 | { |
53 | LONGEST retval; | |
37611a2b AC |
54 | const unsigned char *p; |
55 | const unsigned char *startaddr = addr; | |
56 | const unsigned char *endaddr = startaddr + len; | |
c906108c SS |
57 | |
58 | if (len > (int) sizeof (LONGEST)) | |
8a3fe4f8 AC |
59 | error (_("\ |
60 | That operation is not available on integers of more than %d bytes."), | |
baa6f10b | 61 | (int) sizeof (LONGEST)); |
c906108c SS |
62 | |
63 | /* Start at the most significant end of the integer, and work towards | |
64 | the least significant. */ | |
0d20ae72 | 65 | if (gdbarch_byte_order (current_gdbarch) == BFD_ENDIAN_BIG) |
c906108c SS |
66 | { |
67 | p = startaddr; | |
68 | /* Do the sign extension once at the start. */ | |
c5aa993b | 69 | retval = ((LONGEST) * p ^ 0x80) - 0x80; |
c906108c SS |
70 | for (++p; p < endaddr; ++p) |
71 | retval = (retval << 8) | *p; | |
72 | } | |
73 | else | |
74 | { | |
75 | p = endaddr - 1; | |
76 | /* Do the sign extension once at the start. */ | |
c5aa993b | 77 | retval = ((LONGEST) * p ^ 0x80) - 0x80; |
c906108c SS |
78 | for (--p; p >= startaddr; --p) |
79 | retval = (retval << 8) | *p; | |
80 | } | |
81 | return retval; | |
82 | } | |
83 | ||
84 | ULONGEST | |
0d509538 | 85 | extract_unsigned_integer (const gdb_byte *addr, int len) |
c906108c SS |
86 | { |
87 | ULONGEST retval; | |
37611a2b AC |
88 | const unsigned char *p; |
89 | const unsigned char *startaddr = addr; | |
90 | const unsigned char *endaddr = startaddr + len; | |
c906108c SS |
91 | |
92 | if (len > (int) sizeof (ULONGEST)) | |
8a3fe4f8 AC |
93 | error (_("\ |
94 | That operation is not available on integers of more than %d bytes."), | |
baa6f10b | 95 | (int) sizeof (ULONGEST)); |
c906108c SS |
96 | |
97 | /* Start at the most significant end of the integer, and work towards | |
98 | the least significant. */ | |
99 | retval = 0; | |
0d20ae72 | 100 | if (gdbarch_byte_order (current_gdbarch) == BFD_ENDIAN_BIG) |
c906108c SS |
101 | { |
102 | for (p = startaddr; p < endaddr; ++p) | |
103 | retval = (retval << 8) | *p; | |
104 | } | |
105 | else | |
106 | { | |
107 | for (p = endaddr - 1; p >= startaddr; --p) | |
108 | retval = (retval << 8) | *p; | |
109 | } | |
110 | return retval; | |
111 | } | |
112 | ||
113 | /* Sometimes a long long unsigned integer can be extracted as a | |
114 | LONGEST value. This is done so that we can print these values | |
115 | better. If this integer can be converted to a LONGEST, this | |
116 | function returns 1 and sets *PVAL. Otherwise it returns 0. */ | |
117 | ||
118 | int | |
0d509538 AC |
119 | extract_long_unsigned_integer (const gdb_byte *addr, int orig_len, |
120 | LONGEST *pval) | |
c906108c | 121 | { |
0d509538 AC |
122 | const gdb_byte *p; |
123 | const gdb_byte *first_addr; | |
c906108c SS |
124 | int len; |
125 | ||
126 | len = orig_len; | |
0d20ae72 | 127 | if (gdbarch_byte_order (current_gdbarch) == BFD_ENDIAN_BIG) |
c906108c | 128 | { |
0d509538 AC |
129 | for (p = addr; |
130 | len > (int) sizeof (LONGEST) && p < addr + orig_len; | |
c906108c SS |
131 | p++) |
132 | { | |
133 | if (*p == 0) | |
134 | len--; | |
135 | else | |
136 | break; | |
137 | } | |
138 | first_addr = p; | |
139 | } | |
140 | else | |
141 | { | |
0d509538 AC |
142 | first_addr = addr; |
143 | for (p = addr + orig_len - 1; | |
144 | len > (int) sizeof (LONGEST) && p >= addr; | |
c906108c SS |
145 | p--) |
146 | { | |
147 | if (*p == 0) | |
148 | len--; | |
149 | else | |
150 | break; | |
151 | } | |
152 | } | |
153 | ||
154 | if (len <= (int) sizeof (LONGEST)) | |
155 | { | |
156 | *pval = (LONGEST) extract_unsigned_integer (first_addr, | |
157 | sizeof (LONGEST)); | |
158 | return 1; | |
159 | } | |
160 | ||
161 | return 0; | |
162 | } | |
163 | ||
4478b372 | 164 | |
4478b372 JB |
165 | /* Treat the bytes at BUF as a pointer of type TYPE, and return the |
166 | address it represents. */ | |
167 | CORE_ADDR | |
0d509538 | 168 | extract_typed_address (const gdb_byte *buf, struct type *type) |
4478b372 JB |
169 | { |
170 | if (TYPE_CODE (type) != TYPE_CODE_PTR | |
171 | && TYPE_CODE (type) != TYPE_CODE_REF) | |
8e65ff28 | 172 | internal_error (__FILE__, __LINE__, |
e2e0b3e5 AC |
173 | _("extract_typed_address: " |
174 | "type is not a pointer or reference")); | |
4478b372 | 175 | |
50810684 | 176 | return gdbarch_pointer_to_address (get_type_arch (type), type, buf); |
4478b372 JB |
177 | } |
178 | ||
179 | ||
c906108c | 180 | void |
0d509538 | 181 | store_signed_integer (gdb_byte *addr, int len, LONGEST val) |
c906108c | 182 | { |
0d509538 AC |
183 | gdb_byte *p; |
184 | gdb_byte *startaddr = addr; | |
185 | gdb_byte *endaddr = startaddr + len; | |
c906108c SS |
186 | |
187 | /* Start at the least significant end of the integer, and work towards | |
188 | the most significant. */ | |
0d20ae72 | 189 | if (gdbarch_byte_order (current_gdbarch) == BFD_ENDIAN_BIG) |
c906108c SS |
190 | { |
191 | for (p = endaddr - 1; p >= startaddr; --p) | |
192 | { | |
193 | *p = val & 0xff; | |
194 | val >>= 8; | |
195 | } | |
196 | } | |
197 | else | |
198 | { | |
199 | for (p = startaddr; p < endaddr; ++p) | |
200 | { | |
201 | *p = val & 0xff; | |
202 | val >>= 8; | |
203 | } | |
204 | } | |
205 | } | |
206 | ||
207 | void | |
0d509538 | 208 | store_unsigned_integer (gdb_byte *addr, int len, ULONGEST val) |
c906108c SS |
209 | { |
210 | unsigned char *p; | |
c5aa993b | 211 | unsigned char *startaddr = (unsigned char *) addr; |
c906108c SS |
212 | unsigned char *endaddr = startaddr + len; |
213 | ||
214 | /* Start at the least significant end of the integer, and work towards | |
215 | the most significant. */ | |
0d20ae72 | 216 | if (gdbarch_byte_order (current_gdbarch) == BFD_ENDIAN_BIG) |
c906108c SS |
217 | { |
218 | for (p = endaddr - 1; p >= startaddr; --p) | |
219 | { | |
220 | *p = val & 0xff; | |
221 | val >>= 8; | |
222 | } | |
223 | } | |
224 | else | |
225 | { | |
226 | for (p = startaddr; p < endaddr; ++p) | |
227 | { | |
228 | *p = val & 0xff; | |
229 | val >>= 8; | |
230 | } | |
231 | } | |
232 | } | |
233 | ||
4478b372 JB |
234 | /* Store the address ADDR as a pointer of type TYPE at BUF, in target |
235 | form. */ | |
236 | void | |
0d509538 | 237 | store_typed_address (gdb_byte *buf, struct type *type, CORE_ADDR addr) |
4478b372 JB |
238 | { |
239 | if (TYPE_CODE (type) != TYPE_CODE_PTR | |
240 | && TYPE_CODE (type) != TYPE_CODE_REF) | |
8e65ff28 | 241 | internal_error (__FILE__, __LINE__, |
e2e0b3e5 AC |
242 | _("store_typed_address: " |
243 | "type is not a pointer or reference")); | |
4478b372 | 244 | |
50810684 | 245 | gdbarch_address_to_pointer (get_type_arch (type), type, buf, addr); |
4478b372 JB |
246 | } |
247 | ||
248 | ||
249 | ||
376c9600 AC |
250 | /* Return a `value' with the contents of (virtual or cooked) register |
251 | REGNUM as found in the specified FRAME. The register's type is | |
9c5ea4d9 | 252 | determined by register_type(). */ |
c906108c | 253 | |
3d6d86c6 | 254 | struct value * |
376c9600 | 255 | value_of_register (int regnum, struct frame_info *frame) |
c906108c | 256 | { |
e9e45075 | 257 | struct gdbarch *gdbarch = get_frame_arch (frame); |
c906108c SS |
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 | 266 | registers. Catch them early so that the target never sees them. */ |
e9e45075 UW |
267 | if (regnum >= gdbarch_num_regs (gdbarch) |
268 | + gdbarch_num_pseudo_regs (gdbarch)) | |
eb8bc282 | 269 | return value_of_user_reg (regnum, frame); |
0406ec40 | 270 | |
ac2adee5 | 271 | frame_register (frame, regnum, &optim, &lval, &addr, &realnum, raw_buffer); |
c906108c | 272 | |
e9e45075 | 273 | reg_val = allocate_value (register_type (gdbarch, regnum)); |
c906108c | 274 | |
990a07ab | 275 | memcpy (value_contents_raw (reg_val), raw_buffer, |
e9e45075 | 276 | register_size (gdbarch, regnum)); |
c906108c | 277 | VALUE_LVAL (reg_val) = lval; |
42ae5230 | 278 | set_value_address (reg_val, addr); |
9ee8fc9d | 279 | VALUE_REGNUM (reg_val) = regnum; |
feb13ab0 | 280 | set_value_optimized_out (reg_val, optim); |
0c16dd26 | 281 | VALUE_FRAME_ID (reg_val) = get_frame_id (frame); |
c906108c SS |
282 | return reg_val; |
283 | } | |
4478b372 | 284 | |
9214ee5f DJ |
285 | /* Return a `value' with the contents of (virtual or cooked) register |
286 | REGNUM as found in the specified FRAME. The register's type is | |
287 | determined by register_type(). The value is not fetched. */ | |
288 | ||
289 | struct value * | |
290 | value_of_register_lazy (struct frame_info *frame, int regnum) | |
291 | { | |
292 | struct gdbarch *gdbarch = get_frame_arch (frame); | |
293 | struct value *reg_val; | |
294 | ||
295 | gdb_assert (regnum < (gdbarch_num_regs (gdbarch) | |
296 | + gdbarch_num_pseudo_regs (gdbarch))); | |
297 | ||
298 | /* We should have a valid (i.e. non-sentinel) frame. */ | |
299 | gdb_assert (frame_id_p (get_frame_id (frame))); | |
300 | ||
301 | reg_val = allocate_value (register_type (gdbarch, regnum)); | |
302 | VALUE_LVAL (reg_val) = lval_register; | |
303 | VALUE_REGNUM (reg_val) = regnum; | |
304 | VALUE_FRAME_ID (reg_val) = get_frame_id (frame); | |
305 | set_value_lazy (reg_val, 1); | |
306 | return reg_val; | |
307 | } | |
308 | ||
4478b372 JB |
309 | /* Given a pointer of type TYPE in target form in BUF, return the |
310 | address it represents. */ | |
311 | CORE_ADDR | |
9898f801 UW |
312 | unsigned_pointer_to_address (struct gdbarch *gdbarch, |
313 | struct type *type, const gdb_byte *buf) | |
4478b372 | 314 | { |
af1342ab | 315 | return extract_unsigned_integer (buf, TYPE_LENGTH (type)); |
4478b372 JB |
316 | } |
317 | ||
ac2e2ef7 | 318 | CORE_ADDR |
9898f801 UW |
319 | signed_pointer_to_address (struct gdbarch *gdbarch, |
320 | struct type *type, const gdb_byte *buf) | |
ac2e2ef7 AC |
321 | { |
322 | return extract_signed_integer (buf, TYPE_LENGTH (type)); | |
323 | } | |
4478b372 JB |
324 | |
325 | /* Given an address, store it as a pointer of type TYPE in target | |
326 | format in BUF. */ | |
327 | void | |
9898f801 UW |
328 | unsigned_address_to_pointer (struct gdbarch *gdbarch, struct type *type, |
329 | gdb_byte *buf, CORE_ADDR addr) | |
4478b372 | 330 | { |
fbd9dcd3 | 331 | store_unsigned_integer (buf, TYPE_LENGTH (type), addr); |
4478b372 JB |
332 | } |
333 | ||
ac2e2ef7 | 334 | void |
9898f801 UW |
335 | address_to_signed_pointer (struct gdbarch *gdbarch, struct type *type, |
336 | gdb_byte *buf, CORE_ADDR addr) | |
ac2e2ef7 AC |
337 | { |
338 | store_signed_integer (buf, TYPE_LENGTH (type), addr); | |
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 SS |
346 | { |
347 | switch (SYMBOL_CLASS (sym)) | |
348 | { | |
349 | /* All cases listed explicitly so that gcc -Wall will detect it if | |
c5aa993b | 350 | we failed to consider one. */ |
4c2df51b | 351 | case LOC_COMPUTED: |
a67af2b9 | 352 | /* FIXME: cagney/2004-01-26: It should be possible to |
768a979c | 353 | unconditionally call the SYMBOL_COMPUTED_OPS method when available. |
d3efc286 | 354 | Unfortunately DWARF 2 stores the frame-base (instead of the |
a67af2b9 AC |
355 | function) location in a function's symbol. Oops! For the |
356 | moment enable this when/where applicable. */ | |
768a979c | 357 | return SYMBOL_COMPUTED_OPS (sym)->read_needs_frame (sym); |
4c2df51b | 358 | |
c906108c SS |
359 | case LOC_REGISTER: |
360 | case LOC_ARG: | |
361 | case LOC_REF_ARG: | |
c906108c SS |
362 | case LOC_REGPARM_ADDR: |
363 | case LOC_LOCAL: | |
c906108c SS |
364 | return 1; |
365 | ||
366 | case LOC_UNDEF: | |
367 | case LOC_CONST: | |
368 | case LOC_STATIC: | |
c906108c SS |
369 | case LOC_TYPEDEF: |
370 | ||
371 | case LOC_LABEL: | |
372 | /* Getting the address of a label can be done independently of the block, | |
c5aa993b JM |
373 | even if some *uses* of that address wouldn't work so well without |
374 | the right frame. */ | |
c906108c SS |
375 | |
376 | case LOC_BLOCK: | |
377 | case LOC_CONST_BYTES: | |
378 | case LOC_UNRESOLVED: | |
379 | case LOC_OPTIMIZED_OUT: | |
380 | return 0; | |
381 | } | |
382 | return 1; | |
383 | } | |
384 | ||
385 | /* Given a struct symbol for a variable, | |
386 | and a stack frame id, read the value of the variable | |
387 | and return a (pointer to a) struct value containing the value. | |
61212c0f | 388 | If the variable cannot be found, return a zero pointer. */ |
c906108c | 389 | |
3d6d86c6 | 390 | struct value * |
aa1ee363 | 391 | read_var_value (struct symbol *var, struct frame_info *frame) |
c906108c | 392 | { |
52f0bd74 | 393 | struct value *v; |
c906108c SS |
394 | struct type *type = SYMBOL_TYPE (var); |
395 | CORE_ADDR addr; | |
52f0bd74 | 396 | int len; |
c906108c | 397 | |
bb044262 | 398 | if (SYMBOL_CLASS (var) == LOC_COMPUTED |
2a2d4dc3 | 399 | || SYMBOL_CLASS (var) == LOC_REGISTER) |
bb044262 DJ |
400 | /* These cases do not use V. */ |
401 | v = NULL; | |
402 | else | |
403 | { | |
404 | v = allocate_value (type); | |
405 | VALUE_LVAL (v) = lval_memory; /* The most likely possibility. */ | |
406 | } | |
c906108c SS |
407 | |
408 | len = TYPE_LENGTH (type); | |
409 | ||
61212c0f UW |
410 | if (symbol_read_needs_frame (var)) |
411 | gdb_assert (frame); | |
c906108c SS |
412 | |
413 | switch (SYMBOL_CLASS (var)) | |
414 | { | |
415 | case LOC_CONST: | |
416 | /* Put the constant back in target format. */ | |
990a07ab | 417 | store_signed_integer (value_contents_raw (v), len, |
c906108c SS |
418 | (LONGEST) SYMBOL_VALUE (var)); |
419 | VALUE_LVAL (v) = not_lval; | |
420 | return v; | |
421 | ||
422 | case LOC_LABEL: | |
423 | /* Put the constant back in target format. */ | |
424 | if (overlay_debugging) | |
4478b372 JB |
425 | { |
426 | CORE_ADDR addr | |
427 | = symbol_overlayed_address (SYMBOL_VALUE_ADDRESS (var), | |
714835d5 | 428 | SYMBOL_OBJ_SECTION (var)); |
990a07ab | 429 | store_typed_address (value_contents_raw (v), type, addr); |
4478b372 | 430 | } |
c906108c | 431 | else |
990a07ab | 432 | store_typed_address (value_contents_raw (v), type, |
4478b372 | 433 | SYMBOL_VALUE_ADDRESS (var)); |
c906108c SS |
434 | VALUE_LVAL (v) = not_lval; |
435 | return v; | |
436 | ||
437 | case LOC_CONST_BYTES: | |
438 | { | |
4e38b386 | 439 | memcpy (value_contents_raw (v), SYMBOL_VALUE_BYTES (var), len); |
c906108c SS |
440 | VALUE_LVAL (v) = not_lval; |
441 | return v; | |
442 | } | |
443 | ||
444 | case LOC_STATIC: | |
445 | if (overlay_debugging) | |
446 | addr = symbol_overlayed_address (SYMBOL_VALUE_ADDRESS (var), | |
714835d5 | 447 | SYMBOL_OBJ_SECTION (var)); |
c906108c SS |
448 | else |
449 | addr = SYMBOL_VALUE_ADDRESS (var); | |
450 | break; | |
451 | ||
c906108c | 452 | case LOC_ARG: |
da62e633 | 453 | addr = get_frame_args_address (frame); |
c906108c SS |
454 | if (!addr) |
455 | return 0; | |
456 | addr += SYMBOL_VALUE (var); | |
457 | break; | |
458 | ||
459 | case LOC_REF_ARG: | |
f76febae AC |
460 | { |
461 | struct value *ref; | |
462 | CORE_ADDR argref; | |
da62e633 | 463 | argref = get_frame_args_address (frame); |
f76febae AC |
464 | if (!argref) |
465 | return 0; | |
466 | argref += SYMBOL_VALUE (var); | |
00a4c844 | 467 | ref = value_at (lookup_pointer_type (type), argref); |
1aa20aa8 | 468 | addr = value_as_address (ref); |
f76febae AC |
469 | break; |
470 | } | |
c906108c SS |
471 | |
472 | case LOC_LOCAL: | |
da62e633 | 473 | addr = get_frame_locals_address (frame); |
c906108c SS |
474 | addr += SYMBOL_VALUE (var); |
475 | break; | |
476 | ||
c906108c | 477 | case LOC_TYPEDEF: |
8a3fe4f8 | 478 | error (_("Cannot look up value of a typedef")); |
c906108c SS |
479 | break; |
480 | ||
481 | case LOC_BLOCK: | |
482 | if (overlay_debugging) | |
42ae5230 TT |
483 | set_value_address (v, symbol_overlayed_address |
484 | (BLOCK_START (SYMBOL_BLOCK_VALUE (var)), SYMBOL_OBJ_SECTION (var))); | |
c906108c | 485 | else |
42ae5230 | 486 | set_value_address (v, BLOCK_START (SYMBOL_BLOCK_VALUE (var))); |
c906108c SS |
487 | return v; |
488 | ||
489 | case LOC_REGISTER: | |
c906108c SS |
490 | case LOC_REGPARM_ADDR: |
491 | { | |
768a979c UW |
492 | int regno = SYMBOL_REGISTER_OPS (var) |
493 | ->register_number (var, get_frame_arch (frame)); | |
3d6d86c6 | 494 | struct value *regval; |
c906108c | 495 | |
c906108c SS |
496 | if (SYMBOL_CLASS (var) == LOC_REGPARM_ADDR) |
497 | { | |
498 | regval = value_from_register (lookup_pointer_type (type), | |
c5aa993b | 499 | regno, |
c906108c SS |
500 | frame); |
501 | ||
502 | if (regval == NULL) | |
8a3fe4f8 | 503 | error (_("Value of register variable not available.")); |
c906108c | 504 | |
1aa20aa8 | 505 | addr = value_as_address (regval); |
c906108c SS |
506 | VALUE_LVAL (v) = lval_memory; |
507 | } | |
508 | else | |
509 | { | |
510 | regval = value_from_register (type, regno, frame); | |
511 | ||
512 | if (regval == NULL) | |
8a3fe4f8 | 513 | error (_("Value of register variable not available.")); |
c906108c SS |
514 | return regval; |
515 | } | |
516 | } | |
517 | break; | |
518 | ||
4c2df51b | 519 | case LOC_COMPUTED: |
a67af2b9 | 520 | /* FIXME: cagney/2004-01-26: It should be possible to |
768a979c | 521 | unconditionally call the SYMBOL_COMPUTED_OPS method when available. |
d3efc286 | 522 | Unfortunately DWARF 2 stores the frame-base (instead of the |
a67af2b9 AC |
523 | function) location in a function's symbol. Oops! For the |
524 | moment enable this when/where applicable. */ | |
768a979c | 525 | return SYMBOL_COMPUTED_OPS (var)->read_variable (var, frame); |
4c2df51b | 526 | |
c906108c SS |
527 | case LOC_UNRESOLVED: |
528 | { | |
529 | struct minimal_symbol *msym; | |
e0740f77 | 530 | struct obj_section *obj_section; |
c906108c | 531 | |
3567439c | 532 | msym = lookup_minimal_symbol (SYMBOL_LINKAGE_NAME (var), NULL, NULL); |
c906108c SS |
533 | if (msym == NULL) |
534 | return 0; | |
535 | if (overlay_debugging) | |
536 | addr = symbol_overlayed_address (SYMBOL_VALUE_ADDRESS (msym), | |
714835d5 | 537 | SYMBOL_OBJ_SECTION (msym)); |
c906108c SS |
538 | else |
539 | addr = SYMBOL_VALUE_ADDRESS (msym); | |
e0740f77 JK |
540 | |
541 | obj_section = SYMBOL_OBJ_SECTION (msym); | |
542 | if (obj_section | |
543 | && (obj_section->the_bfd_section->flags & SEC_THREAD_LOCAL) != 0) | |
544 | addr = target_translate_tls_address (obj_section->objfile, addr); | |
c906108c SS |
545 | } |
546 | break; | |
547 | ||
548 | case LOC_OPTIMIZED_OUT: | |
549 | VALUE_LVAL (v) = not_lval; | |
feb13ab0 | 550 | set_value_optimized_out (v, 1); |
c906108c SS |
551 | return v; |
552 | ||
553 | default: | |
8a3fe4f8 | 554 | error (_("Cannot look up value of a botched symbol.")); |
c906108c SS |
555 | break; |
556 | } | |
557 | ||
42ae5230 | 558 | set_value_address (v, addr); |
dfa52d88 | 559 | set_value_lazy (v, 1); |
c906108c SS |
560 | return v; |
561 | } | |
562 | ||
9acbedc0 UW |
563 | /* Install default attributes for register values. */ |
564 | ||
565 | struct value * | |
566 | default_value_from_register (struct type *type, int regnum, | |
567 | struct frame_info *frame) | |
568 | { | |
569 | struct gdbarch *gdbarch = get_frame_arch (frame); | |
570 | int len = TYPE_LENGTH (type); | |
571 | struct value *value = allocate_value (type); | |
572 | ||
573 | VALUE_LVAL (value) = lval_register; | |
574 | VALUE_FRAME_ID (value) = get_frame_id (frame); | |
575 | VALUE_REGNUM (value) = regnum; | |
576 | ||
577 | /* Any structure stored in more than one register will always be | |
578 | an integral number of registers. Otherwise, you need to do | |
579 | some fiddling with the last register copied here for little | |
580 | endian machines. */ | |
e9e45075 | 581 | if (gdbarch_byte_order (gdbarch) == BFD_ENDIAN_BIG |
9acbedc0 UW |
582 | && len < register_size (gdbarch, regnum)) |
583 | /* Big-endian, and we want less than full size. */ | |
584 | set_value_offset (value, register_size (gdbarch, regnum) - len); | |
585 | else | |
586 | set_value_offset (value, 0); | |
587 | ||
588 | return value; | |
589 | } | |
590 | ||
00fa51f6 | 591 | /* Return a value of type TYPE, stored in register REGNUM, in frame FRAME. */ |
c906108c | 592 | |
3d6d86c6 | 593 | struct value * |
fba45db2 | 594 | value_from_register (struct type *type, int regnum, struct frame_info *frame) |
c906108c | 595 | { |
ff2e87ac | 596 | struct gdbarch *gdbarch = get_frame_arch (frame); |
9acbedc0 UW |
597 | struct type *type1 = check_typedef (type); |
598 | struct value *v; | |
599 | ||
e9e45075 | 600 | if (gdbarch_convert_register_p (gdbarch, regnum, type1)) |
ff2e87ac AC |
601 | { |
602 | /* The ISA/ABI need to something weird when obtaining the | |
603 | specified value from this register. It might need to | |
604 | re-order non-adjacent, starting with REGNUM (see MIPS and | |
605 | i386). It might need to convert the [float] register into | |
606 | the corresponding [integer] type (see Alpha). The assumption | |
c1afe53d | 607 | is that gdbarch_register_to_value populates the entire value |
ff2e87ac | 608 | including the location. */ |
9acbedc0 UW |
609 | v = allocate_value (type); |
610 | VALUE_LVAL (v) = lval_register; | |
611 | VALUE_FRAME_ID (v) = get_frame_id (frame); | |
612 | VALUE_REGNUM (v) = regnum; | |
e9e45075 | 613 | gdbarch_register_to_value (gdbarch, |
c1afe53d | 614 | frame, regnum, type1, value_contents_raw (v)); |
ff2e87ac AC |
615 | } |
616 | else | |
c906108c | 617 | { |
ff2e87ac | 618 | int len = TYPE_LENGTH (type); |
00fa51f6 | 619 | |
9acbedc0 UW |
620 | /* Construct the value. */ |
621 | v = gdbarch_value_from_register (gdbarch, type, regnum, frame); | |
00fa51f6 UW |
622 | |
623 | /* Get the data. */ | |
624 | if (!get_frame_register_bytes (frame, regnum, value_offset (v), len, | |
625 | value_contents_raw (v))) | |
626 | set_value_optimized_out (v, 1); | |
c906108c | 627 | } |
c906108c SS |
628 | return v; |
629 | } | |
ff2e87ac | 630 | |
0b2b0195 UW |
631 | /* Return contents of register REGNUM in frame FRAME as address, |
632 | interpreted as value of type TYPE. Will abort if register | |
633 | value is not available. */ | |
634 | ||
635 | CORE_ADDR | |
636 | address_from_register (struct type *type, int regnum, struct frame_info *frame) | |
637 | { | |
638 | struct value *value; | |
639 | CORE_ADDR result; | |
640 | ||
641 | value = value_from_register (type, regnum, frame); | |
642 | gdb_assert (value); | |
643 | ||
644 | result = value_as_address (value); | |
645 | release_value (value); | |
646 | value_free (value); | |
647 | ||
648 | return result; | |
649 | } |