Commit | Line | Data |
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c906108c | 1 | /* Low level packing and unpacking of values 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, 2002, 2003, 2004, 2005, 2006, 2007 | |
4f2aea11 | 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 "gdb_string.h" | |
26 | #include "symtab.h" | |
27 | #include "gdbtypes.h" | |
28 | #include "value.h" | |
29 | #include "gdbcore.h" | |
c906108c SS |
30 | #include "command.h" |
31 | #include "gdbcmd.h" | |
32 | #include "target.h" | |
33 | #include "language.h" | |
c906108c | 34 | #include "demangle.h" |
d16aafd8 | 35 | #include "doublest.h" |
5ae326fa | 36 | #include "gdb_assert.h" |
36160dc4 | 37 | #include "regcache.h" |
fe898f56 | 38 | #include "block.h" |
c906108c SS |
39 | |
40 | /* Prototypes for exported functions. */ | |
41 | ||
a14ed312 | 42 | void _initialize_values (void); |
c906108c | 43 | |
91294c83 AC |
44 | struct value |
45 | { | |
46 | /* Type of value; either not an lval, or one of the various | |
47 | different possible kinds of lval. */ | |
48 | enum lval_type lval; | |
49 | ||
50 | /* Is it modifiable? Only relevant if lval != not_lval. */ | |
51 | int modifiable; | |
52 | ||
53 | /* Location of value (if lval). */ | |
54 | union | |
55 | { | |
56 | /* If lval == lval_memory, this is the address in the inferior. | |
57 | If lval == lval_register, this is the byte offset into the | |
58 | registers structure. */ | |
59 | CORE_ADDR address; | |
60 | ||
61 | /* Pointer to internal variable. */ | |
62 | struct internalvar *internalvar; | |
63 | } location; | |
64 | ||
65 | /* Describes offset of a value within lval of a structure in bytes. | |
66 | If lval == lval_memory, this is an offset to the address. If | |
67 | lval == lval_register, this is a further offset from | |
68 | location.address within the registers structure. Note also the | |
69 | member embedded_offset below. */ | |
70 | int offset; | |
71 | ||
72 | /* Only used for bitfields; number of bits contained in them. */ | |
73 | int bitsize; | |
74 | ||
75 | /* Only used for bitfields; position of start of field. For | |
76 | BITS_BIG_ENDIAN=0 targets, it is the position of the LSB. For | |
77 | BITS_BIG_ENDIAN=1 targets, it is the position of the MSB. */ | |
78 | int bitpos; | |
79 | ||
80 | /* Frame register value is relative to. This will be described in | |
81 | the lval enum above as "lval_register". */ | |
82 | struct frame_id frame_id; | |
83 | ||
84 | /* Type of the value. */ | |
85 | struct type *type; | |
86 | ||
87 | /* If a value represents a C++ object, then the `type' field gives | |
88 | the object's compile-time type. If the object actually belongs | |
89 | to some class derived from `type', perhaps with other base | |
90 | classes and additional members, then `type' is just a subobject | |
91 | of the real thing, and the full object is probably larger than | |
92 | `type' would suggest. | |
93 | ||
94 | If `type' is a dynamic class (i.e. one with a vtable), then GDB | |
95 | can actually determine the object's run-time type by looking at | |
96 | the run-time type information in the vtable. When this | |
97 | information is available, we may elect to read in the entire | |
98 | object, for several reasons: | |
99 | ||
100 | - When printing the value, the user would probably rather see the | |
101 | full object, not just the limited portion apparent from the | |
102 | compile-time type. | |
103 | ||
104 | - If `type' has virtual base classes, then even printing `type' | |
105 | alone may require reaching outside the `type' portion of the | |
106 | object to wherever the virtual base class has been stored. | |
107 | ||
108 | When we store the entire object, `enclosing_type' is the run-time | |
109 | type -- the complete object -- and `embedded_offset' is the | |
110 | offset of `type' within that larger type, in bytes. The | |
111 | value_contents() macro takes `embedded_offset' into account, so | |
112 | most GDB code continues to see the `type' portion of the value, | |
113 | just as the inferior would. | |
114 | ||
115 | If `type' is a pointer to an object, then `enclosing_type' is a | |
116 | pointer to the object's run-time type, and `pointed_to_offset' is | |
117 | the offset in bytes from the full object to the pointed-to object | |
118 | -- that is, the value `embedded_offset' would have if we followed | |
119 | the pointer and fetched the complete object. (I don't really see | |
120 | the point. Why not just determine the run-time type when you | |
121 | indirect, and avoid the special case? The contents don't matter | |
122 | until you indirect anyway.) | |
123 | ||
124 | If we're not doing anything fancy, `enclosing_type' is equal to | |
125 | `type', and `embedded_offset' is zero, so everything works | |
126 | normally. */ | |
127 | struct type *enclosing_type; | |
128 | int embedded_offset; | |
129 | int pointed_to_offset; | |
130 | ||
131 | /* Values are stored in a chain, so that they can be deleted easily | |
132 | over calls to the inferior. Values assigned to internal | |
133 | variables or put into the value history are taken off this | |
134 | list. */ | |
135 | struct value *next; | |
136 | ||
137 | /* Register number if the value is from a register. */ | |
138 | short regnum; | |
139 | ||
140 | /* If zero, contents of this value are in the contents field. If | |
141 | nonzero, contents are in inferior memory at address in the | |
142 | location.address field plus the offset field (and the lval field | |
143 | should be lval_memory). | |
144 | ||
145 | WARNING: This field is used by the code which handles watchpoints | |
146 | (see breakpoint.c) to decide whether a particular value can be | |
147 | watched by hardware watchpoints. If the lazy flag is set for | |
148 | some member of a value chain, it is assumed that this member of | |
149 | the chain doesn't need to be watched as part of watching the | |
150 | value itself. This is how GDB avoids watching the entire struct | |
151 | or array when the user wants to watch a single struct member or | |
152 | array element. If you ever change the way lazy flag is set and | |
153 | reset, be sure to consider this use as well! */ | |
154 | char lazy; | |
155 | ||
156 | /* If nonzero, this is the value of a variable which does not | |
157 | actually exist in the program. */ | |
158 | char optimized_out; | |
159 | ||
160 | /* Actual contents of the value. For use of this value; setting it | |
161 | uses the stuff above. Not valid if lazy is nonzero. Target | |
162 | byte-order. We force it to be aligned properly for any possible | |
163 | value. Note that a value therefore extends beyond what is | |
164 | declared here. */ | |
165 | union | |
166 | { | |
fc1a4b47 | 167 | gdb_byte contents[1]; |
91294c83 AC |
168 | DOUBLEST force_doublest_align; |
169 | LONGEST force_longest_align; | |
170 | CORE_ADDR force_core_addr_align; | |
171 | void *force_pointer_align; | |
172 | } aligner; | |
173 | /* Do not add any new members here -- contents above will trash | |
174 | them. */ | |
175 | }; | |
176 | ||
c906108c SS |
177 | /* Prototypes for local functions. */ |
178 | ||
a14ed312 | 179 | static void show_values (char *, int); |
c906108c | 180 | |
a14ed312 | 181 | static void show_convenience (char *, int); |
c906108c | 182 | |
c906108c SS |
183 | |
184 | /* The value-history records all the values printed | |
185 | by print commands during this session. Each chunk | |
186 | records 60 consecutive values. The first chunk on | |
187 | the chain records the most recent values. | |
188 | The total number of values is in value_history_count. */ | |
189 | ||
190 | #define VALUE_HISTORY_CHUNK 60 | |
191 | ||
192 | struct value_history_chunk | |
c5aa993b JM |
193 | { |
194 | struct value_history_chunk *next; | |
f23631e4 | 195 | struct value *values[VALUE_HISTORY_CHUNK]; |
c5aa993b | 196 | }; |
c906108c SS |
197 | |
198 | /* Chain of chunks now in use. */ | |
199 | ||
200 | static struct value_history_chunk *value_history_chain; | |
201 | ||
202 | static int value_history_count; /* Abs number of last entry stored */ | |
203 | \f | |
204 | /* List of all value objects currently allocated | |
205 | (except for those released by calls to release_value) | |
206 | This is so they can be freed after each command. */ | |
207 | ||
f23631e4 | 208 | static struct value *all_values; |
c906108c SS |
209 | |
210 | /* Allocate a value that has the correct length for type TYPE. */ | |
211 | ||
f23631e4 | 212 | struct value * |
fba45db2 | 213 | allocate_value (struct type *type) |
c906108c | 214 | { |
f23631e4 | 215 | struct value *val; |
c906108c SS |
216 | struct type *atype = check_typedef (type); |
217 | ||
5b90c7b5 | 218 | val = (struct value *) xzalloc (sizeof (struct value) + TYPE_LENGTH (atype)); |
df407dfe | 219 | val->next = all_values; |
c906108c | 220 | all_values = val; |
df407dfe | 221 | val->type = type; |
4754a64e | 222 | val->enclosing_type = type; |
c906108c SS |
223 | VALUE_LVAL (val) = not_lval; |
224 | VALUE_ADDRESS (val) = 0; | |
1df6926e | 225 | VALUE_FRAME_ID (val) = null_frame_id; |
df407dfe AC |
226 | val->offset = 0; |
227 | val->bitpos = 0; | |
228 | val->bitsize = 0; | |
9ee8fc9d | 229 | VALUE_REGNUM (val) = -1; |
d69fe07e | 230 | val->lazy = 0; |
feb13ab0 | 231 | val->optimized_out = 0; |
13c3b5f5 | 232 | val->embedded_offset = 0; |
b44d461b | 233 | val->pointed_to_offset = 0; |
c906108c SS |
234 | val->modifiable = 1; |
235 | return val; | |
236 | } | |
237 | ||
238 | /* Allocate a value that has the correct length | |
239 | for COUNT repetitions type TYPE. */ | |
240 | ||
f23631e4 | 241 | struct value * |
fba45db2 | 242 | allocate_repeat_value (struct type *type, int count) |
c906108c | 243 | { |
c5aa993b | 244 | int low_bound = current_language->string_lower_bound; /* ??? */ |
c906108c SS |
245 | /* FIXME-type-allocation: need a way to free this type when we are |
246 | done with it. */ | |
247 | struct type *range_type | |
c5aa993b JM |
248 | = create_range_type ((struct type *) NULL, builtin_type_int, |
249 | low_bound, count + low_bound - 1); | |
c906108c SS |
250 | /* FIXME-type-allocation: need a way to free this type when we are |
251 | done with it. */ | |
252 | return allocate_value (create_array_type ((struct type *) NULL, | |
253 | type, range_type)); | |
254 | } | |
255 | ||
df407dfe AC |
256 | /* Accessor methods. */ |
257 | ||
17cf0ecd AC |
258 | struct value * |
259 | value_next (struct value *value) | |
260 | { | |
261 | return value->next; | |
262 | } | |
263 | ||
df407dfe AC |
264 | struct type * |
265 | value_type (struct value *value) | |
266 | { | |
267 | return value->type; | |
268 | } | |
04624583 AC |
269 | void |
270 | deprecated_set_value_type (struct value *value, struct type *type) | |
271 | { | |
272 | value->type = type; | |
273 | } | |
df407dfe AC |
274 | |
275 | int | |
276 | value_offset (struct value *value) | |
277 | { | |
278 | return value->offset; | |
279 | } | |
f5cf64a7 AC |
280 | void |
281 | set_value_offset (struct value *value, int offset) | |
282 | { | |
283 | value->offset = offset; | |
284 | } | |
df407dfe AC |
285 | |
286 | int | |
287 | value_bitpos (struct value *value) | |
288 | { | |
289 | return value->bitpos; | |
290 | } | |
9bbda503 AC |
291 | void |
292 | set_value_bitpos (struct value *value, int bit) | |
293 | { | |
294 | value->bitpos = bit; | |
295 | } | |
df407dfe AC |
296 | |
297 | int | |
298 | value_bitsize (struct value *value) | |
299 | { | |
300 | return value->bitsize; | |
301 | } | |
9bbda503 AC |
302 | void |
303 | set_value_bitsize (struct value *value, int bit) | |
304 | { | |
305 | value->bitsize = bit; | |
306 | } | |
df407dfe | 307 | |
fc1a4b47 | 308 | gdb_byte * |
990a07ab AC |
309 | value_contents_raw (struct value *value) |
310 | { | |
311 | return value->aligner.contents + value->embedded_offset; | |
312 | } | |
313 | ||
fc1a4b47 | 314 | gdb_byte * |
990a07ab AC |
315 | value_contents_all_raw (struct value *value) |
316 | { | |
317 | return value->aligner.contents; | |
318 | } | |
319 | ||
4754a64e AC |
320 | struct type * |
321 | value_enclosing_type (struct value *value) | |
322 | { | |
323 | return value->enclosing_type; | |
324 | } | |
325 | ||
fc1a4b47 | 326 | const gdb_byte * |
46615f07 AC |
327 | value_contents_all (struct value *value) |
328 | { | |
329 | if (value->lazy) | |
330 | value_fetch_lazy (value); | |
331 | return value->aligner.contents; | |
332 | } | |
333 | ||
d69fe07e AC |
334 | int |
335 | value_lazy (struct value *value) | |
336 | { | |
337 | return value->lazy; | |
338 | } | |
339 | ||
dfa52d88 AC |
340 | void |
341 | set_value_lazy (struct value *value, int val) | |
342 | { | |
343 | value->lazy = val; | |
344 | } | |
345 | ||
fc1a4b47 | 346 | const gdb_byte * |
0fd88904 AC |
347 | value_contents (struct value *value) |
348 | { | |
349 | return value_contents_writeable (value); | |
350 | } | |
351 | ||
fc1a4b47 | 352 | gdb_byte * |
0fd88904 AC |
353 | value_contents_writeable (struct value *value) |
354 | { | |
355 | if (value->lazy) | |
356 | value_fetch_lazy (value); | |
fc0c53a0 | 357 | return value_contents_raw (value); |
0fd88904 AC |
358 | } |
359 | ||
a6c442d8 MK |
360 | /* Return non-zero if VAL1 and VAL2 have the same contents. Note that |
361 | this function is different from value_equal; in C the operator == | |
362 | can return 0 even if the two values being compared are equal. */ | |
363 | ||
364 | int | |
365 | value_contents_equal (struct value *val1, struct value *val2) | |
366 | { | |
367 | struct type *type1; | |
368 | struct type *type2; | |
369 | int len; | |
370 | ||
371 | type1 = check_typedef (value_type (val1)); | |
372 | type2 = check_typedef (value_type (val2)); | |
373 | len = TYPE_LENGTH (type1); | |
374 | if (len != TYPE_LENGTH (type2)) | |
375 | return 0; | |
376 | ||
377 | return (memcmp (value_contents (val1), value_contents (val2), len) == 0); | |
378 | } | |
379 | ||
feb13ab0 AC |
380 | int |
381 | value_optimized_out (struct value *value) | |
382 | { | |
383 | return value->optimized_out; | |
384 | } | |
385 | ||
386 | void | |
387 | set_value_optimized_out (struct value *value, int val) | |
388 | { | |
389 | value->optimized_out = val; | |
390 | } | |
13c3b5f5 AC |
391 | |
392 | int | |
393 | value_embedded_offset (struct value *value) | |
394 | { | |
395 | return value->embedded_offset; | |
396 | } | |
397 | ||
398 | void | |
399 | set_value_embedded_offset (struct value *value, int val) | |
400 | { | |
401 | value->embedded_offset = val; | |
402 | } | |
b44d461b AC |
403 | |
404 | int | |
405 | value_pointed_to_offset (struct value *value) | |
406 | { | |
407 | return value->pointed_to_offset; | |
408 | } | |
409 | ||
410 | void | |
411 | set_value_pointed_to_offset (struct value *value, int val) | |
412 | { | |
413 | value->pointed_to_offset = val; | |
414 | } | |
13bb5560 AC |
415 | |
416 | enum lval_type * | |
417 | deprecated_value_lval_hack (struct value *value) | |
418 | { | |
419 | return &value->lval; | |
420 | } | |
421 | ||
422 | CORE_ADDR * | |
423 | deprecated_value_address_hack (struct value *value) | |
424 | { | |
425 | return &value->location.address; | |
426 | } | |
427 | ||
428 | struct internalvar ** | |
429 | deprecated_value_internalvar_hack (struct value *value) | |
430 | { | |
431 | return &value->location.internalvar; | |
432 | } | |
433 | ||
434 | struct frame_id * | |
435 | deprecated_value_frame_id_hack (struct value *value) | |
436 | { | |
437 | return &value->frame_id; | |
438 | } | |
439 | ||
440 | short * | |
441 | deprecated_value_regnum_hack (struct value *value) | |
442 | { | |
443 | return &value->regnum; | |
444 | } | |
88e3b34b AC |
445 | |
446 | int | |
447 | deprecated_value_modifiable (struct value *value) | |
448 | { | |
449 | return value->modifiable; | |
450 | } | |
451 | void | |
452 | deprecated_set_value_modifiable (struct value *value, int modifiable) | |
453 | { | |
454 | value->modifiable = modifiable; | |
455 | } | |
990a07ab | 456 | \f |
c906108c SS |
457 | /* Return a mark in the value chain. All values allocated after the |
458 | mark is obtained (except for those released) are subject to being freed | |
459 | if a subsequent value_free_to_mark is passed the mark. */ | |
f23631e4 | 460 | struct value * |
fba45db2 | 461 | value_mark (void) |
c906108c SS |
462 | { |
463 | return all_values; | |
464 | } | |
465 | ||
466 | /* Free all values allocated since MARK was obtained by value_mark | |
467 | (except for those released). */ | |
468 | void | |
f23631e4 | 469 | value_free_to_mark (struct value *mark) |
c906108c | 470 | { |
f23631e4 AC |
471 | struct value *val; |
472 | struct value *next; | |
c906108c SS |
473 | |
474 | for (val = all_values; val && val != mark; val = next) | |
475 | { | |
df407dfe | 476 | next = val->next; |
c906108c SS |
477 | value_free (val); |
478 | } | |
479 | all_values = val; | |
480 | } | |
481 | ||
482 | /* Free all the values that have been allocated (except for those released). | |
483 | Called after each command, successful or not. */ | |
484 | ||
485 | void | |
fba45db2 | 486 | free_all_values (void) |
c906108c | 487 | { |
f23631e4 AC |
488 | struct value *val; |
489 | struct value *next; | |
c906108c SS |
490 | |
491 | for (val = all_values; val; val = next) | |
492 | { | |
df407dfe | 493 | next = val->next; |
c906108c SS |
494 | value_free (val); |
495 | } | |
496 | ||
497 | all_values = 0; | |
498 | } | |
499 | ||
500 | /* Remove VAL from the chain all_values | |
501 | so it will not be freed automatically. */ | |
502 | ||
503 | void | |
f23631e4 | 504 | release_value (struct value *val) |
c906108c | 505 | { |
f23631e4 | 506 | struct value *v; |
c906108c SS |
507 | |
508 | if (all_values == val) | |
509 | { | |
510 | all_values = val->next; | |
511 | return; | |
512 | } | |
513 | ||
514 | for (v = all_values; v; v = v->next) | |
515 | { | |
516 | if (v->next == val) | |
517 | { | |
518 | v->next = val->next; | |
519 | break; | |
520 | } | |
521 | } | |
522 | } | |
523 | ||
524 | /* Release all values up to mark */ | |
f23631e4 AC |
525 | struct value * |
526 | value_release_to_mark (struct value *mark) | |
c906108c | 527 | { |
f23631e4 AC |
528 | struct value *val; |
529 | struct value *next; | |
c906108c | 530 | |
df407dfe AC |
531 | for (val = next = all_values; next; next = next->next) |
532 | if (next->next == mark) | |
c906108c | 533 | { |
df407dfe AC |
534 | all_values = next->next; |
535 | next->next = NULL; | |
c906108c SS |
536 | return val; |
537 | } | |
538 | all_values = 0; | |
539 | return val; | |
540 | } | |
541 | ||
542 | /* Return a copy of the value ARG. | |
543 | It contains the same contents, for same memory address, | |
544 | but it's a different block of storage. */ | |
545 | ||
f23631e4 AC |
546 | struct value * |
547 | value_copy (struct value *arg) | |
c906108c | 548 | { |
4754a64e | 549 | struct type *encl_type = value_enclosing_type (arg); |
f23631e4 | 550 | struct value *val = allocate_value (encl_type); |
df407dfe | 551 | val->type = arg->type; |
c906108c | 552 | VALUE_LVAL (val) = VALUE_LVAL (arg); |
6f7c8fc2 | 553 | val->location = arg->location; |
df407dfe AC |
554 | val->offset = arg->offset; |
555 | val->bitpos = arg->bitpos; | |
556 | val->bitsize = arg->bitsize; | |
1df6926e | 557 | VALUE_FRAME_ID (val) = VALUE_FRAME_ID (arg); |
9ee8fc9d | 558 | VALUE_REGNUM (val) = VALUE_REGNUM (arg); |
d69fe07e | 559 | val->lazy = arg->lazy; |
feb13ab0 | 560 | val->optimized_out = arg->optimized_out; |
13c3b5f5 | 561 | val->embedded_offset = value_embedded_offset (arg); |
b44d461b | 562 | val->pointed_to_offset = arg->pointed_to_offset; |
c906108c | 563 | val->modifiable = arg->modifiable; |
d69fe07e | 564 | if (!value_lazy (val)) |
c906108c | 565 | { |
990a07ab | 566 | memcpy (value_contents_all_raw (val), value_contents_all_raw (arg), |
4754a64e | 567 | TYPE_LENGTH (value_enclosing_type (arg))); |
c906108c SS |
568 | |
569 | } | |
570 | return val; | |
571 | } | |
572 | \f | |
573 | /* Access to the value history. */ | |
574 | ||
575 | /* Record a new value in the value history. | |
576 | Returns the absolute history index of the entry. | |
577 | Result of -1 indicates the value was not saved; otherwise it is the | |
578 | value history index of this new item. */ | |
579 | ||
580 | int | |
f23631e4 | 581 | record_latest_value (struct value *val) |
c906108c SS |
582 | { |
583 | int i; | |
584 | ||
585 | /* We don't want this value to have anything to do with the inferior anymore. | |
586 | In particular, "set $1 = 50" should not affect the variable from which | |
587 | the value was taken, and fast watchpoints should be able to assume that | |
588 | a value on the value history never changes. */ | |
d69fe07e | 589 | if (value_lazy (val)) |
c906108c SS |
590 | value_fetch_lazy (val); |
591 | /* We preserve VALUE_LVAL so that the user can find out where it was fetched | |
592 | from. This is a bit dubious, because then *&$1 does not just return $1 | |
593 | but the current contents of that location. c'est la vie... */ | |
594 | val->modifiable = 0; | |
595 | release_value (val); | |
596 | ||
597 | /* Here we treat value_history_count as origin-zero | |
598 | and applying to the value being stored now. */ | |
599 | ||
600 | i = value_history_count % VALUE_HISTORY_CHUNK; | |
601 | if (i == 0) | |
602 | { | |
f23631e4 | 603 | struct value_history_chunk *new |
c5aa993b JM |
604 | = (struct value_history_chunk *) |
605 | xmalloc (sizeof (struct value_history_chunk)); | |
c906108c SS |
606 | memset (new->values, 0, sizeof new->values); |
607 | new->next = value_history_chain; | |
608 | value_history_chain = new; | |
609 | } | |
610 | ||
611 | value_history_chain->values[i] = val; | |
612 | ||
613 | /* Now we regard value_history_count as origin-one | |
614 | and applying to the value just stored. */ | |
615 | ||
616 | return ++value_history_count; | |
617 | } | |
618 | ||
619 | /* Return a copy of the value in the history with sequence number NUM. */ | |
620 | ||
f23631e4 | 621 | struct value * |
fba45db2 | 622 | access_value_history (int num) |
c906108c | 623 | { |
f23631e4 | 624 | struct value_history_chunk *chunk; |
52f0bd74 AC |
625 | int i; |
626 | int absnum = num; | |
c906108c SS |
627 | |
628 | if (absnum <= 0) | |
629 | absnum += value_history_count; | |
630 | ||
631 | if (absnum <= 0) | |
632 | { | |
633 | if (num == 0) | |
8a3fe4f8 | 634 | error (_("The history is empty.")); |
c906108c | 635 | else if (num == 1) |
8a3fe4f8 | 636 | error (_("There is only one value in the history.")); |
c906108c | 637 | else |
8a3fe4f8 | 638 | error (_("History does not go back to $$%d."), -num); |
c906108c SS |
639 | } |
640 | if (absnum > value_history_count) | |
8a3fe4f8 | 641 | error (_("History has not yet reached $%d."), absnum); |
c906108c SS |
642 | |
643 | absnum--; | |
644 | ||
645 | /* Now absnum is always absolute and origin zero. */ | |
646 | ||
647 | chunk = value_history_chain; | |
648 | for (i = (value_history_count - 1) / VALUE_HISTORY_CHUNK - absnum / VALUE_HISTORY_CHUNK; | |
649 | i > 0; i--) | |
650 | chunk = chunk->next; | |
651 | ||
652 | return value_copy (chunk->values[absnum % VALUE_HISTORY_CHUNK]); | |
653 | } | |
654 | ||
c906108c | 655 | static void |
fba45db2 | 656 | show_values (char *num_exp, int from_tty) |
c906108c | 657 | { |
52f0bd74 | 658 | int i; |
f23631e4 | 659 | struct value *val; |
c906108c SS |
660 | static int num = 1; |
661 | ||
662 | if (num_exp) | |
663 | { | |
c5aa993b JM |
664 | /* "info history +" should print from the stored position. |
665 | "info history <exp>" should print around value number <exp>. */ | |
c906108c | 666 | if (num_exp[0] != '+' || num_exp[1] != '\0') |
bb518678 | 667 | num = parse_and_eval_long (num_exp) - 5; |
c906108c SS |
668 | } |
669 | else | |
670 | { | |
671 | /* "info history" means print the last 10 values. */ | |
672 | num = value_history_count - 9; | |
673 | } | |
674 | ||
675 | if (num <= 0) | |
676 | num = 1; | |
677 | ||
678 | for (i = num; i < num + 10 && i <= value_history_count; i++) | |
679 | { | |
680 | val = access_value_history (i); | |
a3f17187 | 681 | printf_filtered (("$%d = "), i); |
c906108c | 682 | value_print (val, gdb_stdout, 0, Val_pretty_default); |
a3f17187 | 683 | printf_filtered (("\n")); |
c906108c SS |
684 | } |
685 | ||
686 | /* The next "info history +" should start after what we just printed. */ | |
687 | num += 10; | |
688 | ||
689 | /* Hitting just return after this command should do the same thing as | |
690 | "info history +". If num_exp is null, this is unnecessary, since | |
691 | "info history +" is not useful after "info history". */ | |
692 | if (from_tty && num_exp) | |
693 | { | |
694 | num_exp[0] = '+'; | |
695 | num_exp[1] = '\0'; | |
696 | } | |
697 | } | |
698 | \f | |
699 | /* Internal variables. These are variables within the debugger | |
700 | that hold values assigned by debugger commands. | |
701 | The user refers to them with a '$' prefix | |
702 | that does not appear in the variable names stored internally. */ | |
703 | ||
704 | static struct internalvar *internalvars; | |
705 | ||
53e5f3cf AS |
706 | /* If the variable does not already exist create it and give it the value given. |
707 | If no value is given then the default is zero. */ | |
708 | static void | |
709 | init_if_undefined_command (char* args, int from_tty) | |
710 | { | |
711 | struct internalvar* intvar; | |
712 | ||
713 | /* Parse the expression - this is taken from set_command(). */ | |
714 | struct expression *expr = parse_expression (args); | |
715 | register struct cleanup *old_chain = | |
716 | make_cleanup (free_current_contents, &expr); | |
717 | ||
718 | /* Validate the expression. | |
719 | Was the expression an assignment? | |
720 | Or even an expression at all? */ | |
721 | if (expr->nelts == 0 || expr->elts[0].opcode != BINOP_ASSIGN) | |
722 | error (_("Init-if-undefined requires an assignment expression.")); | |
723 | ||
724 | /* Extract the variable from the parsed expression. | |
725 | In the case of an assign the lvalue will be in elts[1] and elts[2]. */ | |
726 | if (expr->elts[1].opcode != OP_INTERNALVAR) | |
727 | error (_("The first parameter to init-if-undefined should be a GDB variable.")); | |
728 | intvar = expr->elts[2].internalvar; | |
729 | ||
730 | /* Only evaluate the expression if the lvalue is void. | |
731 | This may still fail if the expresssion is invalid. */ | |
732 | if (TYPE_CODE (value_type (intvar->value)) == TYPE_CODE_VOID) | |
733 | evaluate_expression (expr); | |
734 | ||
735 | do_cleanups (old_chain); | |
736 | } | |
737 | ||
738 | ||
c906108c SS |
739 | /* Look up an internal variable with name NAME. NAME should not |
740 | normally include a dollar sign. | |
741 | ||
742 | If the specified internal variable does not exist, | |
743 | one is created, with a void value. */ | |
744 | ||
745 | struct internalvar * | |
fba45db2 | 746 | lookup_internalvar (char *name) |
c906108c | 747 | { |
52f0bd74 | 748 | struct internalvar *var; |
c906108c SS |
749 | |
750 | for (var = internalvars; var; var = var->next) | |
5cb316ef | 751 | if (strcmp (var->name, name) == 0) |
c906108c SS |
752 | return var; |
753 | ||
754 | var = (struct internalvar *) xmalloc (sizeof (struct internalvar)); | |
1754f103 | 755 | var->name = concat (name, (char *)NULL); |
c906108c | 756 | var->value = allocate_value (builtin_type_void); |
d3c139e9 | 757 | var->endian = TARGET_BYTE_ORDER; |
c906108c SS |
758 | release_value (var->value); |
759 | var->next = internalvars; | |
760 | internalvars = var; | |
761 | return var; | |
762 | } | |
763 | ||
f23631e4 | 764 | struct value * |
fba45db2 | 765 | value_of_internalvar (struct internalvar *var) |
c906108c | 766 | { |
f23631e4 | 767 | struct value *val; |
d3c139e9 AS |
768 | int i, j; |
769 | gdb_byte temp; | |
c906108c | 770 | |
c906108c | 771 | val = value_copy (var->value); |
d69fe07e | 772 | if (value_lazy (val)) |
c906108c SS |
773 | value_fetch_lazy (val); |
774 | VALUE_LVAL (val) = lval_internalvar; | |
775 | VALUE_INTERNALVAR (val) = var; | |
d3c139e9 AS |
776 | |
777 | /* Values are always stored in the target's byte order. When connected to a | |
778 | target this will most likely always be correct, so there's normally no | |
779 | need to worry about it. | |
780 | ||
781 | However, internal variables can be set up before the target endian is | |
782 | known and so may become out of date. Fix it up before anybody sees. | |
783 | ||
784 | Internal variables usually hold simple scalar values, and we can | |
785 | correct those. More complex values (e.g. structures and floating | |
786 | point types) are left alone, because they would be too complicated | |
787 | to correct. */ | |
788 | ||
789 | if (var->endian != TARGET_BYTE_ORDER) | |
790 | { | |
791 | gdb_byte *array = value_contents_raw (val); | |
792 | struct type *type = check_typedef (value_enclosing_type (val)); | |
793 | switch (TYPE_CODE (type)) | |
794 | { | |
795 | case TYPE_CODE_INT: | |
796 | case TYPE_CODE_PTR: | |
797 | /* Reverse the bytes. */ | |
798 | for (i = 0, j = TYPE_LENGTH (type) - 1; i < j; i++, j--) | |
799 | { | |
800 | temp = array[j]; | |
801 | array[j] = array[i]; | |
802 | array[i] = temp; | |
803 | } | |
804 | break; | |
805 | } | |
806 | } | |
807 | ||
c906108c SS |
808 | return val; |
809 | } | |
810 | ||
811 | void | |
fba45db2 | 812 | set_internalvar_component (struct internalvar *var, int offset, int bitpos, |
f23631e4 | 813 | int bitsize, struct value *newval) |
c906108c | 814 | { |
fc1a4b47 | 815 | gdb_byte *addr = value_contents_writeable (var->value) + offset; |
c906108c | 816 | |
c906108c SS |
817 | if (bitsize) |
818 | modify_field (addr, value_as_long (newval), | |
819 | bitpos, bitsize); | |
820 | else | |
0fd88904 | 821 | memcpy (addr, value_contents (newval), TYPE_LENGTH (value_type (newval))); |
c906108c SS |
822 | } |
823 | ||
824 | void | |
f23631e4 | 825 | set_internalvar (struct internalvar *var, struct value *val) |
c906108c | 826 | { |
f23631e4 | 827 | struct value *newval; |
c906108c | 828 | |
c906108c SS |
829 | newval = value_copy (val); |
830 | newval->modifiable = 1; | |
831 | ||
832 | /* Force the value to be fetched from the target now, to avoid problems | |
833 | later when this internalvar is referenced and the target is gone or | |
834 | has changed. */ | |
d69fe07e | 835 | if (value_lazy (newval)) |
c906108c SS |
836 | value_fetch_lazy (newval); |
837 | ||
838 | /* Begin code which must not call error(). If var->value points to | |
839 | something free'd, an error() obviously leaves a dangling pointer. | |
840 | But we also get a danling pointer if var->value points to | |
841 | something in the value chain (i.e., before release_value is | |
842 | called), because after the error free_all_values will get called before | |
843 | long. */ | |
b8c9b27d | 844 | xfree (var->value); |
c906108c | 845 | var->value = newval; |
d3c139e9 | 846 | var->endian = TARGET_BYTE_ORDER; |
c906108c SS |
847 | release_value (newval); |
848 | /* End code which must not call error(). */ | |
849 | } | |
850 | ||
851 | char * | |
fba45db2 | 852 | internalvar_name (struct internalvar *var) |
c906108c SS |
853 | { |
854 | return var->name; | |
855 | } | |
856 | ||
ae5a43e0 DJ |
857 | /* Update VALUE before discarding OBJFILE. COPIED_TYPES is used to |
858 | prevent cycles / duplicates. */ | |
859 | ||
860 | static void | |
861 | preserve_one_value (struct value *value, struct objfile *objfile, | |
862 | htab_t copied_types) | |
863 | { | |
864 | if (TYPE_OBJFILE (value->type) == objfile) | |
865 | value->type = copy_type_recursive (objfile, value->type, copied_types); | |
866 | ||
867 | if (TYPE_OBJFILE (value->enclosing_type) == objfile) | |
868 | value->enclosing_type = copy_type_recursive (objfile, | |
869 | value->enclosing_type, | |
870 | copied_types); | |
871 | } | |
872 | ||
873 | /* Update the internal variables and value history when OBJFILE is | |
874 | discarded; we must copy the types out of the objfile. New global types | |
875 | will be created for every convenience variable which currently points to | |
876 | this objfile's types, and the convenience variables will be adjusted to | |
877 | use the new global types. */ | |
c906108c SS |
878 | |
879 | void | |
ae5a43e0 | 880 | preserve_values (struct objfile *objfile) |
c906108c | 881 | { |
ae5a43e0 DJ |
882 | htab_t copied_types; |
883 | struct value_history_chunk *cur; | |
52f0bd74 | 884 | struct internalvar *var; |
ae5a43e0 | 885 | int i; |
c906108c | 886 | |
ae5a43e0 DJ |
887 | /* Create the hash table. We allocate on the objfile's obstack, since |
888 | it is soon to be deleted. */ | |
889 | copied_types = create_copied_types_hash (objfile); | |
890 | ||
891 | for (cur = value_history_chain; cur; cur = cur->next) | |
892 | for (i = 0; i < VALUE_HISTORY_CHUNK; i++) | |
893 | if (cur->values[i]) | |
894 | preserve_one_value (cur->values[i], objfile, copied_types); | |
895 | ||
896 | for (var = internalvars; var; var = var->next) | |
897 | preserve_one_value (var->value, objfile, copied_types); | |
898 | ||
899 | htab_delete (copied_types); | |
c906108c SS |
900 | } |
901 | ||
902 | static void | |
fba45db2 | 903 | show_convenience (char *ignore, int from_tty) |
c906108c | 904 | { |
52f0bd74 | 905 | struct internalvar *var; |
c906108c SS |
906 | int varseen = 0; |
907 | ||
908 | for (var = internalvars; var; var = var->next) | |
909 | { | |
c906108c SS |
910 | if (!varseen) |
911 | { | |
912 | varseen = 1; | |
913 | } | |
a3f17187 | 914 | printf_filtered (("$%s = "), var->name); |
d3c139e9 AS |
915 | value_print (value_of_internalvar (var), gdb_stdout, |
916 | 0, Val_pretty_default); | |
a3f17187 | 917 | printf_filtered (("\n")); |
c906108c SS |
918 | } |
919 | if (!varseen) | |
a3f17187 AC |
920 | printf_unfiltered (_("\ |
921 | No debugger convenience variables now defined.\n\ | |
c906108c | 922 | Convenience variables have names starting with \"$\";\n\ |
a3f17187 | 923 | use \"set\" as in \"set $foo = 5\" to define them.\n")); |
c906108c SS |
924 | } |
925 | \f | |
926 | /* Extract a value as a C number (either long or double). | |
927 | Knows how to convert fixed values to double, or | |
928 | floating values to long. | |
929 | Does not deallocate the value. */ | |
930 | ||
931 | LONGEST | |
f23631e4 | 932 | value_as_long (struct value *val) |
c906108c SS |
933 | { |
934 | /* This coerces arrays and functions, which is necessary (e.g. | |
935 | in disassemble_command). It also dereferences references, which | |
936 | I suspect is the most logical thing to do. */ | |
994b9211 | 937 | val = coerce_array (val); |
0fd88904 | 938 | return unpack_long (value_type (val), value_contents (val)); |
c906108c SS |
939 | } |
940 | ||
941 | DOUBLEST | |
f23631e4 | 942 | value_as_double (struct value *val) |
c906108c SS |
943 | { |
944 | DOUBLEST foo; | |
945 | int inv; | |
c5aa993b | 946 | |
0fd88904 | 947 | foo = unpack_double (value_type (val), value_contents (val), &inv); |
c906108c | 948 | if (inv) |
8a3fe4f8 | 949 | error (_("Invalid floating value found in program.")); |
c906108c SS |
950 | return foo; |
951 | } | |
4478b372 JB |
952 | /* Extract a value as a C pointer. Does not deallocate the value. |
953 | Note that val's type may not actually be a pointer; value_as_long | |
954 | handles all the cases. */ | |
c906108c | 955 | CORE_ADDR |
f23631e4 | 956 | value_as_address (struct value *val) |
c906108c SS |
957 | { |
958 | /* Assume a CORE_ADDR can fit in a LONGEST (for now). Not sure | |
959 | whether we want this to be true eventually. */ | |
960 | #if 0 | |
961 | /* ADDR_BITS_REMOVE is wrong if we are being called for a | |
962 | non-address (e.g. argument to "signal", "info break", etc.), or | |
963 | for pointers to char, in which the low bits *are* significant. */ | |
c5aa993b | 964 | return ADDR_BITS_REMOVE (value_as_long (val)); |
c906108c | 965 | #else |
f312f057 JB |
966 | |
967 | /* There are several targets (IA-64, PowerPC, and others) which | |
968 | don't represent pointers to functions as simply the address of | |
969 | the function's entry point. For example, on the IA-64, a | |
970 | function pointer points to a two-word descriptor, generated by | |
971 | the linker, which contains the function's entry point, and the | |
972 | value the IA-64 "global pointer" register should have --- to | |
973 | support position-independent code. The linker generates | |
974 | descriptors only for those functions whose addresses are taken. | |
975 | ||
976 | On such targets, it's difficult for GDB to convert an arbitrary | |
977 | function address into a function pointer; it has to either find | |
978 | an existing descriptor for that function, or call malloc and | |
979 | build its own. On some targets, it is impossible for GDB to | |
980 | build a descriptor at all: the descriptor must contain a jump | |
981 | instruction; data memory cannot be executed; and code memory | |
982 | cannot be modified. | |
983 | ||
984 | Upon entry to this function, if VAL is a value of type `function' | |
985 | (that is, TYPE_CODE (VALUE_TYPE (val)) == TYPE_CODE_FUNC), then | |
986 | VALUE_ADDRESS (val) is the address of the function. This is what | |
987 | you'll get if you evaluate an expression like `main'. The call | |
988 | to COERCE_ARRAY below actually does all the usual unary | |
989 | conversions, which includes converting values of type `function' | |
990 | to `pointer to function'. This is the challenging conversion | |
991 | discussed above. Then, `unpack_long' will convert that pointer | |
992 | back into an address. | |
993 | ||
994 | So, suppose the user types `disassemble foo' on an architecture | |
995 | with a strange function pointer representation, on which GDB | |
996 | cannot build its own descriptors, and suppose further that `foo' | |
997 | has no linker-built descriptor. The address->pointer conversion | |
998 | will signal an error and prevent the command from running, even | |
999 | though the next step would have been to convert the pointer | |
1000 | directly back into the same address. | |
1001 | ||
1002 | The following shortcut avoids this whole mess. If VAL is a | |
1003 | function, just return its address directly. */ | |
df407dfe AC |
1004 | if (TYPE_CODE (value_type (val)) == TYPE_CODE_FUNC |
1005 | || TYPE_CODE (value_type (val)) == TYPE_CODE_METHOD) | |
f312f057 JB |
1006 | return VALUE_ADDRESS (val); |
1007 | ||
994b9211 | 1008 | val = coerce_array (val); |
fc0c74b1 AC |
1009 | |
1010 | /* Some architectures (e.g. Harvard), map instruction and data | |
1011 | addresses onto a single large unified address space. For | |
1012 | instance: An architecture may consider a large integer in the | |
1013 | range 0x10000000 .. 0x1000ffff to already represent a data | |
1014 | addresses (hence not need a pointer to address conversion) while | |
1015 | a small integer would still need to be converted integer to | |
1016 | pointer to address. Just assume such architectures handle all | |
1017 | integer conversions in a single function. */ | |
1018 | ||
1019 | /* JimB writes: | |
1020 | ||
1021 | I think INTEGER_TO_ADDRESS is a good idea as proposed --- but we | |
1022 | must admonish GDB hackers to make sure its behavior matches the | |
1023 | compiler's, whenever possible. | |
1024 | ||
1025 | In general, I think GDB should evaluate expressions the same way | |
1026 | the compiler does. When the user copies an expression out of | |
1027 | their source code and hands it to a `print' command, they should | |
1028 | get the same value the compiler would have computed. Any | |
1029 | deviation from this rule can cause major confusion and annoyance, | |
1030 | and needs to be justified carefully. In other words, GDB doesn't | |
1031 | really have the freedom to do these conversions in clever and | |
1032 | useful ways. | |
1033 | ||
1034 | AndrewC pointed out that users aren't complaining about how GDB | |
1035 | casts integers to pointers; they are complaining that they can't | |
1036 | take an address from a disassembly listing and give it to `x/i'. | |
1037 | This is certainly important. | |
1038 | ||
79dd2d24 | 1039 | Adding an architecture method like integer_to_address() certainly |
fc0c74b1 AC |
1040 | makes it possible for GDB to "get it right" in all circumstances |
1041 | --- the target has complete control over how things get done, so | |
1042 | people can Do The Right Thing for their target without breaking | |
1043 | anyone else. The standard doesn't specify how integers get | |
1044 | converted to pointers; usually, the ABI doesn't either, but | |
1045 | ABI-specific code is a more reasonable place to handle it. */ | |
1046 | ||
df407dfe AC |
1047 | if (TYPE_CODE (value_type (val)) != TYPE_CODE_PTR |
1048 | && TYPE_CODE (value_type (val)) != TYPE_CODE_REF | |
79dd2d24 AC |
1049 | && gdbarch_integer_to_address_p (current_gdbarch)) |
1050 | return gdbarch_integer_to_address (current_gdbarch, value_type (val), | |
0fd88904 | 1051 | value_contents (val)); |
fc0c74b1 | 1052 | |
0fd88904 | 1053 | return unpack_long (value_type (val), value_contents (val)); |
c906108c SS |
1054 | #endif |
1055 | } | |
1056 | \f | |
1057 | /* Unpack raw data (copied from debugee, target byte order) at VALADDR | |
1058 | as a long, or as a double, assuming the raw data is described | |
1059 | by type TYPE. Knows how to convert different sizes of values | |
1060 | and can convert between fixed and floating point. We don't assume | |
1061 | any alignment for the raw data. Return value is in host byte order. | |
1062 | ||
1063 | If you want functions and arrays to be coerced to pointers, and | |
1064 | references to be dereferenced, call value_as_long() instead. | |
1065 | ||
1066 | C++: It is assumed that the front-end has taken care of | |
1067 | all matters concerning pointers to members. A pointer | |
1068 | to member which reaches here is considered to be equivalent | |
1069 | to an INT (or some size). After all, it is only an offset. */ | |
1070 | ||
1071 | LONGEST | |
fc1a4b47 | 1072 | unpack_long (struct type *type, const gdb_byte *valaddr) |
c906108c | 1073 | { |
52f0bd74 AC |
1074 | enum type_code code = TYPE_CODE (type); |
1075 | int len = TYPE_LENGTH (type); | |
1076 | int nosign = TYPE_UNSIGNED (type); | |
c906108c | 1077 | |
c906108c SS |
1078 | switch (code) |
1079 | { | |
1080 | case TYPE_CODE_TYPEDEF: | |
1081 | return unpack_long (check_typedef (type), valaddr); | |
1082 | case TYPE_CODE_ENUM: | |
4f2aea11 | 1083 | case TYPE_CODE_FLAGS: |
c906108c SS |
1084 | case TYPE_CODE_BOOL: |
1085 | case TYPE_CODE_INT: | |
1086 | case TYPE_CODE_CHAR: | |
1087 | case TYPE_CODE_RANGE: | |
0d5de010 | 1088 | case TYPE_CODE_MEMBERPTR: |
c906108c SS |
1089 | if (nosign) |
1090 | return extract_unsigned_integer (valaddr, len); | |
1091 | else | |
1092 | return extract_signed_integer (valaddr, len); | |
1093 | ||
1094 | case TYPE_CODE_FLT: | |
96d2f608 | 1095 | return extract_typed_floating (valaddr, type); |
c906108c SS |
1096 | |
1097 | case TYPE_CODE_PTR: | |
1098 | case TYPE_CODE_REF: | |
1099 | /* Assume a CORE_ADDR can fit in a LONGEST (for now). Not sure | |
c5aa993b | 1100 | whether we want this to be true eventually. */ |
4478b372 | 1101 | return extract_typed_address (valaddr, type); |
c906108c | 1102 | |
c906108c | 1103 | default: |
8a3fe4f8 | 1104 | error (_("Value can't be converted to integer.")); |
c906108c | 1105 | } |
c5aa993b | 1106 | return 0; /* Placate lint. */ |
c906108c SS |
1107 | } |
1108 | ||
1109 | /* Return a double value from the specified type and address. | |
1110 | INVP points to an int which is set to 0 for valid value, | |
1111 | 1 for invalid value (bad float format). In either case, | |
1112 | the returned double is OK to use. Argument is in target | |
1113 | format, result is in host format. */ | |
1114 | ||
1115 | DOUBLEST | |
fc1a4b47 | 1116 | unpack_double (struct type *type, const gdb_byte *valaddr, int *invp) |
c906108c SS |
1117 | { |
1118 | enum type_code code; | |
1119 | int len; | |
1120 | int nosign; | |
1121 | ||
1122 | *invp = 0; /* Assume valid. */ | |
1123 | CHECK_TYPEDEF (type); | |
1124 | code = TYPE_CODE (type); | |
1125 | len = TYPE_LENGTH (type); | |
1126 | nosign = TYPE_UNSIGNED (type); | |
1127 | if (code == TYPE_CODE_FLT) | |
1128 | { | |
75bc7ddf AC |
1129 | /* NOTE: cagney/2002-02-19: There was a test here to see if the |
1130 | floating-point value was valid (using the macro | |
1131 | INVALID_FLOAT). That test/macro have been removed. | |
1132 | ||
1133 | It turns out that only the VAX defined this macro and then | |
1134 | only in a non-portable way. Fixing the portability problem | |
1135 | wouldn't help since the VAX floating-point code is also badly | |
1136 | bit-rotten. The target needs to add definitions for the | |
1137 | methods TARGET_FLOAT_FORMAT and TARGET_DOUBLE_FORMAT - these | |
1138 | exactly describe the target floating-point format. The | |
1139 | problem here is that the corresponding floatformat_vax_f and | |
1140 | floatformat_vax_d values these methods should be set to are | |
1141 | also not defined either. Oops! | |
1142 | ||
1143 | Hopefully someone will add both the missing floatformat | |
ac79b88b DJ |
1144 | definitions and the new cases for floatformat_is_valid (). */ |
1145 | ||
1146 | if (!floatformat_is_valid (floatformat_from_type (type), valaddr)) | |
1147 | { | |
1148 | *invp = 1; | |
1149 | return 0.0; | |
1150 | } | |
1151 | ||
96d2f608 | 1152 | return extract_typed_floating (valaddr, type); |
c906108c SS |
1153 | } |
1154 | else if (nosign) | |
1155 | { | |
1156 | /* Unsigned -- be sure we compensate for signed LONGEST. */ | |
c906108c | 1157 | return (ULONGEST) unpack_long (type, valaddr); |
c906108c SS |
1158 | } |
1159 | else | |
1160 | { | |
1161 | /* Signed -- we are OK with unpack_long. */ | |
1162 | return unpack_long (type, valaddr); | |
1163 | } | |
1164 | } | |
1165 | ||
1166 | /* Unpack raw data (copied from debugee, target byte order) at VALADDR | |
1167 | as a CORE_ADDR, assuming the raw data is described by type TYPE. | |
1168 | We don't assume any alignment for the raw data. Return value is in | |
1169 | host byte order. | |
1170 | ||
1171 | If you want functions and arrays to be coerced to pointers, and | |
1aa20aa8 | 1172 | references to be dereferenced, call value_as_address() instead. |
c906108c SS |
1173 | |
1174 | C++: It is assumed that the front-end has taken care of | |
1175 | all matters concerning pointers to members. A pointer | |
1176 | to member which reaches here is considered to be equivalent | |
1177 | to an INT (or some size). After all, it is only an offset. */ | |
1178 | ||
1179 | CORE_ADDR | |
fc1a4b47 | 1180 | unpack_pointer (struct type *type, const gdb_byte *valaddr) |
c906108c SS |
1181 | { |
1182 | /* Assume a CORE_ADDR can fit in a LONGEST (for now). Not sure | |
1183 | whether we want this to be true eventually. */ | |
1184 | return unpack_long (type, valaddr); | |
1185 | } | |
4478b372 | 1186 | |
c906108c | 1187 | \f |
2c2738a0 DC |
1188 | /* Get the value of the FIELDN'th field (which must be static) of |
1189 | TYPE. Return NULL if the field doesn't exist or has been | |
1190 | optimized out. */ | |
c906108c | 1191 | |
f23631e4 | 1192 | struct value * |
fba45db2 | 1193 | value_static_field (struct type *type, int fieldno) |
c906108c | 1194 | { |
948e66d9 DJ |
1195 | struct value *retval; |
1196 | ||
c906108c SS |
1197 | if (TYPE_FIELD_STATIC_HAS_ADDR (type, fieldno)) |
1198 | { | |
948e66d9 | 1199 | retval = value_at (TYPE_FIELD_TYPE (type, fieldno), |
00a4c844 | 1200 | TYPE_FIELD_STATIC_PHYSADDR (type, fieldno)); |
c906108c SS |
1201 | } |
1202 | else | |
1203 | { | |
1204 | char *phys_name = TYPE_FIELD_STATIC_PHYSNAME (type, fieldno); | |
176620f1 | 1205 | struct symbol *sym = lookup_symbol (phys_name, 0, VAR_DOMAIN, 0, NULL); |
948e66d9 | 1206 | if (sym == NULL) |
c906108c SS |
1207 | { |
1208 | /* With some compilers, e.g. HP aCC, static data members are reported | |
c5aa993b JM |
1209 | as non-debuggable symbols */ |
1210 | struct minimal_symbol *msym = lookup_minimal_symbol (phys_name, NULL, NULL); | |
c906108c SS |
1211 | if (!msym) |
1212 | return NULL; | |
1213 | else | |
c5aa993b | 1214 | { |
948e66d9 | 1215 | retval = value_at (TYPE_FIELD_TYPE (type, fieldno), |
00a4c844 | 1216 | SYMBOL_VALUE_ADDRESS (msym)); |
c906108c SS |
1217 | } |
1218 | } | |
1219 | else | |
1220 | { | |
948e66d9 DJ |
1221 | /* SYM should never have a SYMBOL_CLASS which will require |
1222 | read_var_value to use the FRAME parameter. */ | |
1223 | if (symbol_read_needs_frame (sym)) | |
8a3fe4f8 AC |
1224 | warning (_("static field's value depends on the current " |
1225 | "frame - bad debug info?")); | |
948e66d9 | 1226 | retval = read_var_value (sym, NULL); |
2b127877 | 1227 | } |
948e66d9 DJ |
1228 | if (retval && VALUE_LVAL (retval) == lval_memory) |
1229 | SET_FIELD_PHYSADDR (TYPE_FIELD (type, fieldno), | |
1230 | VALUE_ADDRESS (retval)); | |
c906108c | 1231 | } |
948e66d9 | 1232 | return retval; |
c906108c SS |
1233 | } |
1234 | ||
2b127877 DB |
1235 | /* Change the enclosing type of a value object VAL to NEW_ENCL_TYPE. |
1236 | You have to be careful here, since the size of the data area for the value | |
1237 | is set by the length of the enclosing type. So if NEW_ENCL_TYPE is bigger | |
1238 | than the old enclosing type, you have to allocate more space for the data. | |
1239 | The return value is a pointer to the new version of this value structure. */ | |
1240 | ||
f23631e4 AC |
1241 | struct value * |
1242 | value_change_enclosing_type (struct value *val, struct type *new_encl_type) | |
2b127877 | 1243 | { |
4754a64e | 1244 | if (TYPE_LENGTH (new_encl_type) <= TYPE_LENGTH (value_enclosing_type (val))) |
2b127877 | 1245 | { |
4754a64e | 1246 | val->enclosing_type = new_encl_type; |
2b127877 DB |
1247 | return val; |
1248 | } | |
1249 | else | |
1250 | { | |
f23631e4 AC |
1251 | struct value *new_val; |
1252 | struct value *prev; | |
2b127877 | 1253 | |
f23631e4 | 1254 | new_val = (struct value *) xrealloc (val, sizeof (struct value) + TYPE_LENGTH (new_encl_type)); |
cc303028 | 1255 | |
4754a64e | 1256 | new_val->enclosing_type = new_encl_type; |
cc303028 | 1257 | |
2b127877 DB |
1258 | /* We have to make sure this ends up in the same place in the value |
1259 | chain as the original copy, so it's clean-up behavior is the same. | |
1260 | If the value has been released, this is a waste of time, but there | |
1261 | is no way to tell that in advance, so... */ | |
1262 | ||
1263 | if (val != all_values) | |
1264 | { | |
1265 | for (prev = all_values; prev != NULL; prev = prev->next) | |
1266 | { | |
1267 | if (prev->next == val) | |
1268 | { | |
1269 | prev->next = new_val; | |
1270 | break; | |
1271 | } | |
1272 | } | |
1273 | } | |
1274 | ||
1275 | return new_val; | |
1276 | } | |
1277 | } | |
1278 | ||
c906108c SS |
1279 | /* Given a value ARG1 (offset by OFFSET bytes) |
1280 | of a struct or union type ARG_TYPE, | |
1281 | extract and return the value of one of its (non-static) fields. | |
1282 | FIELDNO says which field. */ | |
1283 | ||
f23631e4 AC |
1284 | struct value * |
1285 | value_primitive_field (struct value *arg1, int offset, | |
aa1ee363 | 1286 | int fieldno, struct type *arg_type) |
c906108c | 1287 | { |
f23631e4 | 1288 | struct value *v; |
52f0bd74 | 1289 | struct type *type; |
c906108c SS |
1290 | |
1291 | CHECK_TYPEDEF (arg_type); | |
1292 | type = TYPE_FIELD_TYPE (arg_type, fieldno); | |
1293 | ||
1294 | /* Handle packed fields */ | |
1295 | ||
1296 | if (TYPE_FIELD_BITSIZE (arg_type, fieldno)) | |
1297 | { | |
1298 | v = value_from_longest (type, | |
1299 | unpack_field_as_long (arg_type, | |
0fd88904 | 1300 | value_contents (arg1) |
c5aa993b | 1301 | + offset, |
c906108c | 1302 | fieldno)); |
df407dfe AC |
1303 | v->bitpos = TYPE_FIELD_BITPOS (arg_type, fieldno) % 8; |
1304 | v->bitsize = TYPE_FIELD_BITSIZE (arg_type, fieldno); | |
1305 | v->offset = value_offset (arg1) + offset | |
2e70b7b9 | 1306 | + TYPE_FIELD_BITPOS (arg_type, fieldno) / 8; |
c906108c SS |
1307 | } |
1308 | else if (fieldno < TYPE_N_BASECLASSES (arg_type)) | |
1309 | { | |
1310 | /* This field is actually a base subobject, so preserve the | |
1311 | entire object's contents for later references to virtual | |
1312 | bases, etc. */ | |
4754a64e | 1313 | v = allocate_value (value_enclosing_type (arg1)); |
df407dfe | 1314 | v->type = type; |
d69fe07e | 1315 | if (value_lazy (arg1)) |
dfa52d88 | 1316 | set_value_lazy (v, 1); |
c906108c | 1317 | else |
990a07ab | 1318 | memcpy (value_contents_all_raw (v), value_contents_all_raw (arg1), |
4754a64e | 1319 | TYPE_LENGTH (value_enclosing_type (arg1))); |
df407dfe | 1320 | v->offset = value_offset (arg1); |
13c3b5f5 AC |
1321 | v->embedded_offset = (offset + value_embedded_offset (arg1) |
1322 | + TYPE_FIELD_BITPOS (arg_type, fieldno) / 8); | |
c906108c SS |
1323 | } |
1324 | else | |
1325 | { | |
1326 | /* Plain old data member */ | |
1327 | offset += TYPE_FIELD_BITPOS (arg_type, fieldno) / 8; | |
1328 | v = allocate_value (type); | |
d69fe07e | 1329 | if (value_lazy (arg1)) |
dfa52d88 | 1330 | set_value_lazy (v, 1); |
c906108c | 1331 | else |
990a07ab AC |
1332 | memcpy (value_contents_raw (v), |
1333 | value_contents_raw (arg1) + offset, | |
c906108c | 1334 | TYPE_LENGTH (type)); |
df407dfe | 1335 | v->offset = (value_offset (arg1) + offset |
13c3b5f5 | 1336 | + value_embedded_offset (arg1)); |
c906108c SS |
1337 | } |
1338 | VALUE_LVAL (v) = VALUE_LVAL (arg1); | |
1339 | if (VALUE_LVAL (arg1) == lval_internalvar) | |
1340 | VALUE_LVAL (v) = lval_internalvar_component; | |
7d85ee02 | 1341 | v->location = arg1->location; |
9ee8fc9d | 1342 | VALUE_REGNUM (v) = VALUE_REGNUM (arg1); |
0c16dd26 | 1343 | VALUE_FRAME_ID (v) = VALUE_FRAME_ID (arg1); |
c906108c SS |
1344 | return v; |
1345 | } | |
1346 | ||
1347 | /* Given a value ARG1 of a struct or union type, | |
1348 | extract and return the value of one of its (non-static) fields. | |
1349 | FIELDNO says which field. */ | |
1350 | ||
f23631e4 | 1351 | struct value * |
aa1ee363 | 1352 | value_field (struct value *arg1, int fieldno) |
c906108c | 1353 | { |
df407dfe | 1354 | return value_primitive_field (arg1, 0, fieldno, value_type (arg1)); |
c906108c SS |
1355 | } |
1356 | ||
1357 | /* Return a non-virtual function as a value. | |
1358 | F is the list of member functions which contains the desired method. | |
0478d61c FF |
1359 | J is an index into F which provides the desired method. |
1360 | ||
1361 | We only use the symbol for its address, so be happy with either a | |
1362 | full symbol or a minimal symbol. | |
1363 | */ | |
c906108c | 1364 | |
f23631e4 AC |
1365 | struct value * |
1366 | value_fn_field (struct value **arg1p, struct fn_field *f, int j, struct type *type, | |
fba45db2 | 1367 | int offset) |
c906108c | 1368 | { |
f23631e4 | 1369 | struct value *v; |
52f0bd74 | 1370 | struct type *ftype = TYPE_FN_FIELD_TYPE (f, j); |
0478d61c | 1371 | char *physname = TYPE_FN_FIELD_PHYSNAME (f, j); |
c906108c | 1372 | struct symbol *sym; |
0478d61c | 1373 | struct minimal_symbol *msym; |
c906108c | 1374 | |
176620f1 | 1375 | sym = lookup_symbol (physname, 0, VAR_DOMAIN, 0, NULL); |
5ae326fa | 1376 | if (sym != NULL) |
0478d61c | 1377 | { |
5ae326fa AC |
1378 | msym = NULL; |
1379 | } | |
1380 | else | |
1381 | { | |
1382 | gdb_assert (sym == NULL); | |
0478d61c | 1383 | msym = lookup_minimal_symbol (physname, NULL, NULL); |
5ae326fa AC |
1384 | if (msym == NULL) |
1385 | return NULL; | |
0478d61c FF |
1386 | } |
1387 | ||
c906108c | 1388 | v = allocate_value (ftype); |
0478d61c FF |
1389 | if (sym) |
1390 | { | |
1391 | VALUE_ADDRESS (v) = BLOCK_START (SYMBOL_BLOCK_VALUE (sym)); | |
1392 | } | |
1393 | else | |
1394 | { | |
1395 | VALUE_ADDRESS (v) = SYMBOL_VALUE_ADDRESS (msym); | |
1396 | } | |
c906108c SS |
1397 | |
1398 | if (arg1p) | |
c5aa993b | 1399 | { |
df407dfe | 1400 | if (type != value_type (*arg1p)) |
c5aa993b JM |
1401 | *arg1p = value_ind (value_cast (lookup_pointer_type (type), |
1402 | value_addr (*arg1p))); | |
1403 | ||
070ad9f0 | 1404 | /* Move the `this' pointer according to the offset. |
c5aa993b JM |
1405 | VALUE_OFFSET (*arg1p) += offset; |
1406 | */ | |
c906108c SS |
1407 | } |
1408 | ||
1409 | return v; | |
1410 | } | |
1411 | ||
c906108c SS |
1412 | \f |
1413 | /* Unpack a field FIELDNO of the specified TYPE, from the anonymous object at | |
1414 | VALADDR. | |
1415 | ||
1416 | Extracting bits depends on endianness of the machine. Compute the | |
1417 | number of least significant bits to discard. For big endian machines, | |
1418 | we compute the total number of bits in the anonymous object, subtract | |
1419 | off the bit count from the MSB of the object to the MSB of the | |
1420 | bitfield, then the size of the bitfield, which leaves the LSB discard | |
1421 | count. For little endian machines, the discard count is simply the | |
1422 | number of bits from the LSB of the anonymous object to the LSB of the | |
1423 | bitfield. | |
1424 | ||
1425 | If the field is signed, we also do sign extension. */ | |
1426 | ||
1427 | LONGEST | |
fc1a4b47 | 1428 | unpack_field_as_long (struct type *type, const gdb_byte *valaddr, int fieldno) |
c906108c SS |
1429 | { |
1430 | ULONGEST val; | |
1431 | ULONGEST valmask; | |
1432 | int bitpos = TYPE_FIELD_BITPOS (type, fieldno); | |
1433 | int bitsize = TYPE_FIELD_BITSIZE (type, fieldno); | |
1434 | int lsbcount; | |
1435 | struct type *field_type; | |
1436 | ||
1437 | val = extract_unsigned_integer (valaddr + bitpos / 8, sizeof (val)); | |
1438 | field_type = TYPE_FIELD_TYPE (type, fieldno); | |
1439 | CHECK_TYPEDEF (field_type); | |
1440 | ||
1441 | /* Extract bits. See comment above. */ | |
1442 | ||
1443 | if (BITS_BIG_ENDIAN) | |
1444 | lsbcount = (sizeof val * 8 - bitpos % 8 - bitsize); | |
1445 | else | |
1446 | lsbcount = (bitpos % 8); | |
1447 | val >>= lsbcount; | |
1448 | ||
1449 | /* If the field does not entirely fill a LONGEST, then zero the sign bits. | |
1450 | If the field is signed, and is negative, then sign extend. */ | |
1451 | ||
1452 | if ((bitsize > 0) && (bitsize < 8 * (int) sizeof (val))) | |
1453 | { | |
1454 | valmask = (((ULONGEST) 1) << bitsize) - 1; | |
1455 | val &= valmask; | |
1456 | if (!TYPE_UNSIGNED (field_type)) | |
1457 | { | |
1458 | if (val & (valmask ^ (valmask >> 1))) | |
1459 | { | |
1460 | val |= ~valmask; | |
1461 | } | |
1462 | } | |
1463 | } | |
1464 | return (val); | |
1465 | } | |
1466 | ||
1467 | /* Modify the value of a bitfield. ADDR points to a block of memory in | |
1468 | target byte order; the bitfield starts in the byte pointed to. FIELDVAL | |
1469 | is the desired value of the field, in host byte order. BITPOS and BITSIZE | |
f4e88c8e PH |
1470 | indicate which bits (in target bit order) comprise the bitfield. |
1471 | Requires 0 < BITSIZE <= lbits, 0 <= BITPOS+BITSIZE <= lbits, and | |
1472 | 0 <= BITPOS, where lbits is the size of a LONGEST in bits. */ | |
c906108c SS |
1473 | |
1474 | void | |
fc1a4b47 | 1475 | modify_field (gdb_byte *addr, LONGEST fieldval, int bitpos, int bitsize) |
c906108c | 1476 | { |
f4e88c8e PH |
1477 | ULONGEST oword; |
1478 | ULONGEST mask = (ULONGEST) -1 >> (8 * sizeof (ULONGEST) - bitsize); | |
c906108c SS |
1479 | |
1480 | /* If a negative fieldval fits in the field in question, chop | |
1481 | off the sign extension bits. */ | |
f4e88c8e PH |
1482 | if ((~fieldval & ~(mask >> 1)) == 0) |
1483 | fieldval &= mask; | |
c906108c SS |
1484 | |
1485 | /* Warn if value is too big to fit in the field in question. */ | |
f4e88c8e | 1486 | if (0 != (fieldval & ~mask)) |
c906108c SS |
1487 | { |
1488 | /* FIXME: would like to include fieldval in the message, but | |
c5aa993b | 1489 | we don't have a sprintf_longest. */ |
8a3fe4f8 | 1490 | warning (_("Value does not fit in %d bits."), bitsize); |
c906108c SS |
1491 | |
1492 | /* Truncate it, otherwise adjoining fields may be corrupted. */ | |
f4e88c8e | 1493 | fieldval &= mask; |
c906108c SS |
1494 | } |
1495 | ||
f4e88c8e | 1496 | oword = extract_unsigned_integer (addr, sizeof oword); |
c906108c SS |
1497 | |
1498 | /* Shifting for bit field depends on endianness of the target machine. */ | |
1499 | if (BITS_BIG_ENDIAN) | |
1500 | bitpos = sizeof (oword) * 8 - bitpos - bitsize; | |
1501 | ||
f4e88c8e | 1502 | oword &= ~(mask << bitpos); |
c906108c SS |
1503 | oword |= fieldval << bitpos; |
1504 | ||
f4e88c8e | 1505 | store_unsigned_integer (addr, sizeof oword, oword); |
c906108c SS |
1506 | } |
1507 | \f | |
1508 | /* Convert C numbers into newly allocated values */ | |
1509 | ||
f23631e4 | 1510 | struct value * |
aa1ee363 | 1511 | value_from_longest (struct type *type, LONGEST num) |
c906108c | 1512 | { |
f23631e4 | 1513 | struct value *val = allocate_value (type); |
52f0bd74 AC |
1514 | enum type_code code; |
1515 | int len; | |
c5aa993b | 1516 | retry: |
c906108c SS |
1517 | code = TYPE_CODE (type); |
1518 | len = TYPE_LENGTH (type); | |
1519 | ||
1520 | switch (code) | |
1521 | { | |
1522 | case TYPE_CODE_TYPEDEF: | |
1523 | type = check_typedef (type); | |
1524 | goto retry; | |
1525 | case TYPE_CODE_INT: | |
1526 | case TYPE_CODE_CHAR: | |
1527 | case TYPE_CODE_ENUM: | |
4f2aea11 | 1528 | case TYPE_CODE_FLAGS: |
c906108c SS |
1529 | case TYPE_CODE_BOOL: |
1530 | case TYPE_CODE_RANGE: | |
0d5de010 | 1531 | case TYPE_CODE_MEMBERPTR: |
990a07ab | 1532 | store_signed_integer (value_contents_raw (val), len, num); |
c906108c | 1533 | break; |
c5aa993b | 1534 | |
c906108c SS |
1535 | case TYPE_CODE_REF: |
1536 | case TYPE_CODE_PTR: | |
990a07ab | 1537 | store_typed_address (value_contents_raw (val), type, (CORE_ADDR) num); |
c906108c | 1538 | break; |
c5aa993b | 1539 | |
c906108c | 1540 | default: |
8a3fe4f8 | 1541 | error (_("Unexpected type (%d) encountered for integer constant."), code); |
c906108c SS |
1542 | } |
1543 | return val; | |
1544 | } | |
1545 | ||
4478b372 JB |
1546 | |
1547 | /* Create a value representing a pointer of type TYPE to the address | |
1548 | ADDR. */ | |
f23631e4 | 1549 | struct value * |
4478b372 JB |
1550 | value_from_pointer (struct type *type, CORE_ADDR addr) |
1551 | { | |
f23631e4 | 1552 | struct value *val = allocate_value (type); |
990a07ab | 1553 | store_typed_address (value_contents_raw (val), type, addr); |
4478b372 JB |
1554 | return val; |
1555 | } | |
1556 | ||
1557 | ||
0f71a2f6 | 1558 | /* Create a value for a string constant to be stored locally |
070ad9f0 | 1559 | (not in the inferior's memory space, but in GDB memory). |
0f71a2f6 JM |
1560 | This is analogous to value_from_longest, which also does not |
1561 | use inferior memory. String shall NOT contain embedded nulls. */ | |
1562 | ||
f23631e4 | 1563 | struct value * |
fba45db2 | 1564 | value_from_string (char *ptr) |
0f71a2f6 | 1565 | { |
f23631e4 | 1566 | struct value *val; |
c5aa993b | 1567 | int len = strlen (ptr); |
0f71a2f6 | 1568 | int lowbound = current_language->string_lower_bound; |
f290d38e AC |
1569 | struct type *string_char_type; |
1570 | struct type *rangetype; | |
1571 | struct type *stringtype; | |
1572 | ||
1573 | rangetype = create_range_type ((struct type *) NULL, | |
1574 | builtin_type_int, | |
1575 | lowbound, len + lowbound - 1); | |
1576 | string_char_type = language_string_char_type (current_language, | |
1577 | current_gdbarch); | |
1578 | stringtype = create_array_type ((struct type *) NULL, | |
1579 | string_char_type, | |
1580 | rangetype); | |
0f71a2f6 | 1581 | val = allocate_value (stringtype); |
990a07ab | 1582 | memcpy (value_contents_raw (val), ptr, len); |
0f71a2f6 JM |
1583 | return val; |
1584 | } | |
1585 | ||
f23631e4 | 1586 | struct value * |
fba45db2 | 1587 | value_from_double (struct type *type, DOUBLEST num) |
c906108c | 1588 | { |
f23631e4 | 1589 | struct value *val = allocate_value (type); |
c906108c | 1590 | struct type *base_type = check_typedef (type); |
52f0bd74 AC |
1591 | enum type_code code = TYPE_CODE (base_type); |
1592 | int len = TYPE_LENGTH (base_type); | |
c906108c SS |
1593 | |
1594 | if (code == TYPE_CODE_FLT) | |
1595 | { | |
990a07ab | 1596 | store_typed_floating (value_contents_raw (val), base_type, num); |
c906108c SS |
1597 | } |
1598 | else | |
8a3fe4f8 | 1599 | error (_("Unexpected type encountered for floating constant.")); |
c906108c SS |
1600 | |
1601 | return val; | |
1602 | } | |
994b9211 AC |
1603 | |
1604 | struct value * | |
1605 | coerce_ref (struct value *arg) | |
1606 | { | |
df407dfe | 1607 | struct type *value_type_arg_tmp = check_typedef (value_type (arg)); |
994b9211 AC |
1608 | if (TYPE_CODE (value_type_arg_tmp) == TYPE_CODE_REF) |
1609 | arg = value_at_lazy (TYPE_TARGET_TYPE (value_type_arg_tmp), | |
df407dfe | 1610 | unpack_pointer (value_type (arg), |
0fd88904 | 1611 | value_contents (arg))); |
994b9211 AC |
1612 | return arg; |
1613 | } | |
1614 | ||
1615 | struct value * | |
1616 | coerce_array (struct value *arg) | |
1617 | { | |
1618 | arg = coerce_ref (arg); | |
1619 | if (current_language->c_style_arrays | |
df407dfe | 1620 | && TYPE_CODE (value_type (arg)) == TYPE_CODE_ARRAY) |
994b9211 | 1621 | arg = value_coerce_array (arg); |
df407dfe | 1622 | if (TYPE_CODE (value_type (arg)) == TYPE_CODE_FUNC) |
994b9211 AC |
1623 | arg = value_coerce_function (arg); |
1624 | return arg; | |
1625 | } | |
1626 | ||
1627 | struct value * | |
1628 | coerce_number (struct value *arg) | |
1629 | { | |
1630 | arg = coerce_array (arg); | |
1631 | arg = coerce_enum (arg); | |
1632 | return arg; | |
1633 | } | |
1634 | ||
1635 | struct value * | |
1636 | coerce_enum (struct value *arg) | |
1637 | { | |
df407dfe | 1638 | if (TYPE_CODE (check_typedef (value_type (arg))) == TYPE_CODE_ENUM) |
994b9211 AC |
1639 | arg = value_cast (builtin_type_unsigned_int, arg); |
1640 | return arg; | |
1641 | } | |
c906108c | 1642 | \f |
c906108c | 1643 | |
74055713 AC |
1644 | /* Should we use DEPRECATED_EXTRACT_STRUCT_VALUE_ADDRESS instead of |
1645 | EXTRACT_RETURN_VALUE? GCC_P is true if compiled with gcc and TYPE | |
1646 | is the type (which is known to be struct, union or array). | |
c906108c SS |
1647 | |
1648 | On most machines, the struct convention is used unless we are | |
1649 | using gcc and the type is of a special size. */ | |
1650 | /* As of about 31 Mar 93, GCC was changed to be compatible with the | |
1651 | native compiler. GCC 2.3.3 was the last release that did it the | |
1652 | old way. Since gcc2_compiled was not changed, we have no | |
1653 | way to correctly win in all cases, so we just do the right thing | |
1654 | for gcc1 and for gcc2 after this change. Thus it loses for gcc | |
1655 | 2.0-2.3.3. This is somewhat unfortunate, but changing gcc2_compiled | |
1656 | would cause more chaos than dealing with some struct returns being | |
1657 | handled wrong. */ | |
bc87dfa0 AC |
1658 | /* NOTE: cagney/2004-06-13: Deleted check for "gcc_p". GCC 1.x is |
1659 | dead. */ | |
c906108c SS |
1660 | |
1661 | int | |
fba45db2 | 1662 | generic_use_struct_convention (int gcc_p, struct type *value_type) |
c5aa993b | 1663 | { |
bc87dfa0 AC |
1664 | return !(TYPE_LENGTH (value_type) == 1 |
1665 | || TYPE_LENGTH (value_type) == 2 | |
1666 | || TYPE_LENGTH (value_type) == 4 | |
1667 | || TYPE_LENGTH (value_type) == 8); | |
c906108c SS |
1668 | } |
1669 | ||
48436ce6 AC |
1670 | /* Return true if the function returning the specified type is using |
1671 | the convention of returning structures in memory (passing in the | |
1672 | address as a hidden first parameter). GCC_P is nonzero if compiled | |
c906108c SS |
1673 | with GCC. */ |
1674 | ||
1675 | int | |
48436ce6 | 1676 | using_struct_return (struct type *value_type, int gcc_p) |
c906108c | 1677 | { |
52f0bd74 | 1678 | enum type_code code = TYPE_CODE (value_type); |
c906108c SS |
1679 | |
1680 | if (code == TYPE_CODE_ERROR) | |
8a3fe4f8 | 1681 | error (_("Function return type unknown.")); |
c906108c | 1682 | |
667e784f AC |
1683 | if (code == TYPE_CODE_VOID) |
1684 | /* A void return value is never in memory. See also corresponding | |
44e5158b | 1685 | code in "print_return_value". */ |
667e784f AC |
1686 | return 0; |
1687 | ||
92ad9cd9 AC |
1688 | /* Probe the architecture for the return-value convention. */ |
1689 | return (gdbarch_return_value (current_gdbarch, value_type, | |
1690 | NULL, NULL, NULL) | |
31db7b6c | 1691 | != RETURN_VALUE_REGISTER_CONVENTION); |
c906108c SS |
1692 | } |
1693 | ||
c906108c | 1694 | void |
fba45db2 | 1695 | _initialize_values (void) |
c906108c | 1696 | { |
1a966eab AC |
1697 | add_cmd ("convenience", no_class, show_convenience, _("\ |
1698 | Debugger convenience (\"$foo\") variables.\n\ | |
c906108c | 1699 | These variables are created when you assign them values;\n\ |
1a966eab AC |
1700 | thus, \"print $foo=1\" gives \"$foo\" the value 1. Values may be any type.\n\ |
1701 | \n\ | |
c906108c SS |
1702 | A few convenience variables are given values automatically:\n\ |
1703 | \"$_\"holds the last address examined with \"x\" or \"info lines\",\n\ | |
1a966eab | 1704 | \"$__\" holds the contents of the last address examined with \"x\"."), |
c906108c SS |
1705 | &showlist); |
1706 | ||
1707 | add_cmd ("values", no_class, show_values, | |
1a966eab | 1708 | _("Elements of value history around item number IDX (or last ten)."), |
c906108c | 1709 | &showlist); |
53e5f3cf AS |
1710 | |
1711 | add_com ("init-if-undefined", class_vars, init_if_undefined_command, _("\ | |
1712 | Initialize a convenience variable if necessary.\n\ | |
1713 | init-if-undefined VARIABLE = EXPRESSION\n\ | |
1714 | Set an internal VARIABLE to the result of the EXPRESSION if it does not\n\ | |
1715 | exist or does not contain a value. The EXPRESSION is not evaluated if the\n\ | |
1716 | VARIABLE is already initialized.")); | |
c906108c | 1717 | } |