Commit | Line | Data |
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c906108c | 1 | /* Low level packing and unpacking of values 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, 2002, 2003, 2004, 2005, 2006, 2007, 2008, |
4c38e0a4 | 5 | 2009, 2010 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" | |
e17c207e | 23 | #include "arch-utils.h" |
c906108c SS |
24 | #include "gdb_string.h" |
25 | #include "symtab.h" | |
26 | #include "gdbtypes.h" | |
27 | #include "value.h" | |
28 | #include "gdbcore.h" | |
c906108c SS |
29 | #include "command.h" |
30 | #include "gdbcmd.h" | |
31 | #include "target.h" | |
32 | #include "language.h" | |
c906108c | 33 | #include "demangle.h" |
d16aafd8 | 34 | #include "doublest.h" |
5ae326fa | 35 | #include "gdb_assert.h" |
36160dc4 | 36 | #include "regcache.h" |
fe898f56 | 37 | #include "block.h" |
27bc4d80 | 38 | #include "dfp.h" |
bccdca4a | 39 | #include "objfiles.h" |
79a45b7d | 40 | #include "valprint.h" |
bc3b79fd | 41 | #include "cli/cli-decode.h" |
c906108c | 42 | |
a08702d6 TJB |
43 | #include "python/python.h" |
44 | ||
0914bcdb SS |
45 | #include "tracepoint.h" |
46 | ||
c906108c SS |
47 | /* Prototypes for exported functions. */ |
48 | ||
a14ed312 | 49 | void _initialize_values (void); |
c906108c | 50 | |
bc3b79fd TJB |
51 | /* Definition of a user function. */ |
52 | struct internal_function | |
53 | { | |
54 | /* The name of the function. It is a bit odd to have this in the | |
55 | function itself -- the user might use a differently-named | |
56 | convenience variable to hold the function. */ | |
57 | char *name; | |
58 | ||
59 | /* The handler. */ | |
60 | internal_function_fn handler; | |
61 | ||
62 | /* User data for the handler. */ | |
63 | void *cookie; | |
64 | }; | |
65 | ||
66 | static struct cmd_list_element *functionlist; | |
67 | ||
91294c83 AC |
68 | struct value |
69 | { | |
70 | /* Type of value; either not an lval, or one of the various | |
71 | different possible kinds of lval. */ | |
72 | enum lval_type lval; | |
73 | ||
74 | /* Is it modifiable? Only relevant if lval != not_lval. */ | |
75 | int modifiable; | |
76 | ||
77 | /* Location of value (if lval). */ | |
78 | union | |
79 | { | |
80 | /* If lval == lval_memory, this is the address in the inferior. | |
81 | If lval == lval_register, this is the byte offset into the | |
82 | registers structure. */ | |
83 | CORE_ADDR address; | |
84 | ||
85 | /* Pointer to internal variable. */ | |
86 | struct internalvar *internalvar; | |
5f5233d4 PA |
87 | |
88 | /* If lval == lval_computed, this is a set of function pointers | |
89 | to use to access and describe the value, and a closure pointer | |
90 | for them to use. */ | |
91 | struct | |
92 | { | |
93 | struct lval_funcs *funcs; /* Functions to call. */ | |
94 | void *closure; /* Closure for those functions to use. */ | |
95 | } computed; | |
91294c83 AC |
96 | } location; |
97 | ||
98 | /* Describes offset of a value within lval of a structure in bytes. | |
99 | If lval == lval_memory, this is an offset to the address. If | |
100 | lval == lval_register, this is a further offset from | |
101 | location.address within the registers structure. Note also the | |
102 | member embedded_offset below. */ | |
103 | int offset; | |
104 | ||
105 | /* Only used for bitfields; number of bits contained in them. */ | |
106 | int bitsize; | |
107 | ||
108 | /* Only used for bitfields; position of start of field. For | |
32c9a795 MD |
109 | gdbarch_bits_big_endian=0 targets, it is the position of the LSB. For |
110 | gdbarch_bits_big_endian=1 targets, it is the position of the MSB. */ | |
91294c83 AC |
111 | int bitpos; |
112 | ||
4ea48cc1 DJ |
113 | /* Only used for bitfields; the containing value. This allows a |
114 | single read from the target when displaying multiple | |
115 | bitfields. */ | |
116 | struct value *parent; | |
117 | ||
91294c83 AC |
118 | /* Frame register value is relative to. This will be described in |
119 | the lval enum above as "lval_register". */ | |
120 | struct frame_id frame_id; | |
121 | ||
122 | /* Type of the value. */ | |
123 | struct type *type; | |
124 | ||
125 | /* If a value represents a C++ object, then the `type' field gives | |
126 | the object's compile-time type. If the object actually belongs | |
127 | to some class derived from `type', perhaps with other base | |
128 | classes and additional members, then `type' is just a subobject | |
129 | of the real thing, and the full object is probably larger than | |
130 | `type' would suggest. | |
131 | ||
132 | If `type' is a dynamic class (i.e. one with a vtable), then GDB | |
133 | can actually determine the object's run-time type by looking at | |
134 | the run-time type information in the vtable. When this | |
135 | information is available, we may elect to read in the entire | |
136 | object, for several reasons: | |
137 | ||
138 | - When printing the value, the user would probably rather see the | |
139 | full object, not just the limited portion apparent from the | |
140 | compile-time type. | |
141 | ||
142 | - If `type' has virtual base classes, then even printing `type' | |
143 | alone may require reaching outside the `type' portion of the | |
144 | object to wherever the virtual base class has been stored. | |
145 | ||
146 | When we store the entire object, `enclosing_type' is the run-time | |
147 | type -- the complete object -- and `embedded_offset' is the | |
148 | offset of `type' within that larger type, in bytes. The | |
149 | value_contents() macro takes `embedded_offset' into account, so | |
150 | most GDB code continues to see the `type' portion of the value, | |
151 | just as the inferior would. | |
152 | ||
153 | If `type' is a pointer to an object, then `enclosing_type' is a | |
154 | pointer to the object's run-time type, and `pointed_to_offset' is | |
155 | the offset in bytes from the full object to the pointed-to object | |
156 | -- that is, the value `embedded_offset' would have if we followed | |
157 | the pointer and fetched the complete object. (I don't really see | |
158 | the point. Why not just determine the run-time type when you | |
159 | indirect, and avoid the special case? The contents don't matter | |
160 | until you indirect anyway.) | |
161 | ||
162 | If we're not doing anything fancy, `enclosing_type' is equal to | |
163 | `type', and `embedded_offset' is zero, so everything works | |
164 | normally. */ | |
165 | struct type *enclosing_type; | |
166 | int embedded_offset; | |
167 | int pointed_to_offset; | |
168 | ||
169 | /* Values are stored in a chain, so that they can be deleted easily | |
170 | over calls to the inferior. Values assigned to internal | |
a08702d6 TJB |
171 | variables, put into the value history or exposed to Python are |
172 | taken off this list. */ | |
91294c83 AC |
173 | struct value *next; |
174 | ||
175 | /* Register number if the value is from a register. */ | |
176 | short regnum; | |
177 | ||
178 | /* If zero, contents of this value are in the contents field. If | |
9214ee5f DJ |
179 | nonzero, contents are in inferior. If the lval field is lval_memory, |
180 | the contents are in inferior memory at location.address plus offset. | |
181 | The lval field may also be lval_register. | |
91294c83 AC |
182 | |
183 | WARNING: This field is used by the code which handles watchpoints | |
184 | (see breakpoint.c) to decide whether a particular value can be | |
185 | watched by hardware watchpoints. If the lazy flag is set for | |
186 | some member of a value chain, it is assumed that this member of | |
187 | the chain doesn't need to be watched as part of watching the | |
188 | value itself. This is how GDB avoids watching the entire struct | |
189 | or array when the user wants to watch a single struct member or | |
190 | array element. If you ever change the way lazy flag is set and | |
191 | reset, be sure to consider this use as well! */ | |
192 | char lazy; | |
193 | ||
194 | /* If nonzero, this is the value of a variable which does not | |
195 | actually exist in the program. */ | |
196 | char optimized_out; | |
197 | ||
42be36b3 CT |
198 | /* If value is a variable, is it initialized or not. */ |
199 | int initialized; | |
200 | ||
4e5d721f DE |
201 | /* If value is from the stack. If this is set, read_stack will be |
202 | used instead of read_memory to enable extra caching. */ | |
203 | int stack; | |
204 | ||
3e3d7139 JG |
205 | /* Actual contents of the value. Target byte-order. NULL or not |
206 | valid if lazy is nonzero. */ | |
207 | gdb_byte *contents; | |
828d3400 DJ |
208 | |
209 | /* The number of references to this value. When a value is created, | |
210 | the value chain holds a reference, so REFERENCE_COUNT is 1. If | |
211 | release_value is called, this value is removed from the chain but | |
212 | the caller of release_value now has a reference to this value. | |
213 | The caller must arrange for a call to value_free later. */ | |
214 | int reference_count; | |
91294c83 AC |
215 | }; |
216 | ||
c906108c SS |
217 | /* Prototypes for local functions. */ |
218 | ||
a14ed312 | 219 | static void show_values (char *, int); |
c906108c | 220 | |
a14ed312 | 221 | static void show_convenience (char *, int); |
c906108c | 222 | |
c906108c SS |
223 | |
224 | /* The value-history records all the values printed | |
225 | by print commands during this session. Each chunk | |
226 | records 60 consecutive values. The first chunk on | |
227 | the chain records the most recent values. | |
228 | The total number of values is in value_history_count. */ | |
229 | ||
230 | #define VALUE_HISTORY_CHUNK 60 | |
231 | ||
232 | struct value_history_chunk | |
c5aa993b JM |
233 | { |
234 | struct value_history_chunk *next; | |
f23631e4 | 235 | struct value *values[VALUE_HISTORY_CHUNK]; |
c5aa993b | 236 | }; |
c906108c SS |
237 | |
238 | /* Chain of chunks now in use. */ | |
239 | ||
240 | static struct value_history_chunk *value_history_chain; | |
241 | ||
242 | static int value_history_count; /* Abs number of last entry stored */ | |
bc3b79fd | 243 | |
c906108c SS |
244 | \f |
245 | /* List of all value objects currently allocated | |
246 | (except for those released by calls to release_value) | |
247 | This is so they can be freed after each command. */ | |
248 | ||
f23631e4 | 249 | static struct value *all_values; |
c906108c | 250 | |
3e3d7139 JG |
251 | /* Allocate a lazy value for type TYPE. Its actual content is |
252 | "lazily" allocated too: the content field of the return value is | |
253 | NULL; it will be allocated when it is fetched from the target. */ | |
c906108c | 254 | |
f23631e4 | 255 | struct value * |
3e3d7139 | 256 | allocate_value_lazy (struct type *type) |
c906108c | 257 | { |
f23631e4 | 258 | struct value *val; |
c54eabfa JK |
259 | |
260 | /* Call check_typedef on our type to make sure that, if TYPE | |
261 | is a TYPE_CODE_TYPEDEF, its length is set to the length | |
262 | of the target type instead of zero. However, we do not | |
263 | replace the typedef type by the target type, because we want | |
264 | to keep the typedef in order to be able to set the VAL's type | |
265 | description correctly. */ | |
266 | check_typedef (type); | |
c906108c | 267 | |
3e3d7139 JG |
268 | val = (struct value *) xzalloc (sizeof (struct value)); |
269 | val->contents = NULL; | |
df407dfe | 270 | val->next = all_values; |
c906108c | 271 | all_values = val; |
df407dfe | 272 | val->type = type; |
4754a64e | 273 | val->enclosing_type = type; |
c906108c | 274 | VALUE_LVAL (val) = not_lval; |
42ae5230 | 275 | val->location.address = 0; |
1df6926e | 276 | VALUE_FRAME_ID (val) = null_frame_id; |
df407dfe AC |
277 | val->offset = 0; |
278 | val->bitpos = 0; | |
279 | val->bitsize = 0; | |
9ee8fc9d | 280 | VALUE_REGNUM (val) = -1; |
3e3d7139 | 281 | val->lazy = 1; |
feb13ab0 | 282 | val->optimized_out = 0; |
13c3b5f5 | 283 | val->embedded_offset = 0; |
b44d461b | 284 | val->pointed_to_offset = 0; |
c906108c | 285 | val->modifiable = 1; |
42be36b3 | 286 | val->initialized = 1; /* Default to initialized. */ |
828d3400 DJ |
287 | |
288 | /* Values start out on the all_values chain. */ | |
289 | val->reference_count = 1; | |
290 | ||
c906108c SS |
291 | return val; |
292 | } | |
293 | ||
3e3d7139 JG |
294 | /* Allocate the contents of VAL if it has not been allocated yet. */ |
295 | ||
296 | void | |
297 | allocate_value_contents (struct value *val) | |
298 | { | |
299 | if (!val->contents) | |
300 | val->contents = (gdb_byte *) xzalloc (TYPE_LENGTH (val->enclosing_type)); | |
301 | } | |
302 | ||
303 | /* Allocate a value and its contents for type TYPE. */ | |
304 | ||
305 | struct value * | |
306 | allocate_value (struct type *type) | |
307 | { | |
308 | struct value *val = allocate_value_lazy (type); | |
a109c7c1 | 309 | |
3e3d7139 JG |
310 | allocate_value_contents (val); |
311 | val->lazy = 0; | |
312 | return val; | |
313 | } | |
314 | ||
c906108c | 315 | /* Allocate a value that has the correct length |
938f5214 | 316 | for COUNT repetitions of type TYPE. */ |
c906108c | 317 | |
f23631e4 | 318 | struct value * |
fba45db2 | 319 | allocate_repeat_value (struct type *type, int count) |
c906108c | 320 | { |
c5aa993b | 321 | int low_bound = current_language->string_lower_bound; /* ??? */ |
c906108c SS |
322 | /* FIXME-type-allocation: need a way to free this type when we are |
323 | done with it. */ | |
e3506a9f UW |
324 | struct type *array_type |
325 | = lookup_array_range_type (type, low_bound, count + low_bound - 1); | |
a109c7c1 | 326 | |
e3506a9f | 327 | return allocate_value (array_type); |
c906108c SS |
328 | } |
329 | ||
5f5233d4 PA |
330 | struct value * |
331 | allocate_computed_value (struct type *type, | |
332 | struct lval_funcs *funcs, | |
333 | void *closure) | |
334 | { | |
335 | struct value *v = allocate_value (type); | |
a109c7c1 | 336 | |
5f5233d4 PA |
337 | VALUE_LVAL (v) = lval_computed; |
338 | v->location.computed.funcs = funcs; | |
339 | v->location.computed.closure = closure; | |
340 | set_value_lazy (v, 1); | |
341 | ||
342 | return v; | |
343 | } | |
344 | ||
df407dfe AC |
345 | /* Accessor methods. */ |
346 | ||
17cf0ecd AC |
347 | struct value * |
348 | value_next (struct value *value) | |
349 | { | |
350 | return value->next; | |
351 | } | |
352 | ||
df407dfe | 353 | struct type * |
0e03807e | 354 | value_type (const struct value *value) |
df407dfe AC |
355 | { |
356 | return value->type; | |
357 | } | |
04624583 AC |
358 | void |
359 | deprecated_set_value_type (struct value *value, struct type *type) | |
360 | { | |
361 | value->type = type; | |
362 | } | |
df407dfe AC |
363 | |
364 | int | |
0e03807e | 365 | value_offset (const struct value *value) |
df407dfe AC |
366 | { |
367 | return value->offset; | |
368 | } | |
f5cf64a7 AC |
369 | void |
370 | set_value_offset (struct value *value, int offset) | |
371 | { | |
372 | value->offset = offset; | |
373 | } | |
df407dfe AC |
374 | |
375 | int | |
0e03807e | 376 | value_bitpos (const struct value *value) |
df407dfe AC |
377 | { |
378 | return value->bitpos; | |
379 | } | |
9bbda503 AC |
380 | void |
381 | set_value_bitpos (struct value *value, int bit) | |
382 | { | |
383 | value->bitpos = bit; | |
384 | } | |
df407dfe AC |
385 | |
386 | int | |
0e03807e | 387 | value_bitsize (const struct value *value) |
df407dfe AC |
388 | { |
389 | return value->bitsize; | |
390 | } | |
9bbda503 AC |
391 | void |
392 | set_value_bitsize (struct value *value, int bit) | |
393 | { | |
394 | value->bitsize = bit; | |
395 | } | |
df407dfe | 396 | |
4ea48cc1 DJ |
397 | struct value * |
398 | value_parent (struct value *value) | |
399 | { | |
400 | return value->parent; | |
401 | } | |
402 | ||
fc1a4b47 | 403 | gdb_byte * |
990a07ab AC |
404 | value_contents_raw (struct value *value) |
405 | { | |
3e3d7139 JG |
406 | allocate_value_contents (value); |
407 | return value->contents + value->embedded_offset; | |
990a07ab AC |
408 | } |
409 | ||
fc1a4b47 | 410 | gdb_byte * |
990a07ab AC |
411 | value_contents_all_raw (struct value *value) |
412 | { | |
3e3d7139 JG |
413 | allocate_value_contents (value); |
414 | return value->contents; | |
990a07ab AC |
415 | } |
416 | ||
4754a64e AC |
417 | struct type * |
418 | value_enclosing_type (struct value *value) | |
419 | { | |
420 | return value->enclosing_type; | |
421 | } | |
422 | ||
0e03807e TT |
423 | static void |
424 | require_not_optimized_out (struct value *value) | |
425 | { | |
426 | if (value->optimized_out) | |
427 | error (_("value has been optimized out")); | |
428 | } | |
429 | ||
fc1a4b47 | 430 | const gdb_byte * |
0e03807e | 431 | value_contents_for_printing (struct value *value) |
46615f07 AC |
432 | { |
433 | if (value->lazy) | |
434 | value_fetch_lazy (value); | |
3e3d7139 | 435 | return value->contents; |
46615f07 AC |
436 | } |
437 | ||
0e03807e TT |
438 | const gdb_byte * |
439 | value_contents_all (struct value *value) | |
440 | { | |
441 | const gdb_byte *result = value_contents_for_printing (value); | |
442 | require_not_optimized_out (value); | |
443 | return result; | |
444 | } | |
445 | ||
d69fe07e AC |
446 | int |
447 | value_lazy (struct value *value) | |
448 | { | |
449 | return value->lazy; | |
450 | } | |
451 | ||
dfa52d88 AC |
452 | void |
453 | set_value_lazy (struct value *value, int val) | |
454 | { | |
455 | value->lazy = val; | |
456 | } | |
457 | ||
4e5d721f DE |
458 | int |
459 | value_stack (struct value *value) | |
460 | { | |
461 | return value->stack; | |
462 | } | |
463 | ||
464 | void | |
465 | set_value_stack (struct value *value, int val) | |
466 | { | |
467 | value->stack = val; | |
468 | } | |
469 | ||
fc1a4b47 | 470 | const gdb_byte * |
0fd88904 AC |
471 | value_contents (struct value *value) |
472 | { | |
0e03807e TT |
473 | const gdb_byte *result = value_contents_writeable (value); |
474 | require_not_optimized_out (value); | |
475 | return result; | |
0fd88904 AC |
476 | } |
477 | ||
fc1a4b47 | 478 | gdb_byte * |
0fd88904 AC |
479 | value_contents_writeable (struct value *value) |
480 | { | |
481 | if (value->lazy) | |
482 | value_fetch_lazy (value); | |
fc0c53a0 | 483 | return value_contents_raw (value); |
0fd88904 AC |
484 | } |
485 | ||
a6c442d8 MK |
486 | /* Return non-zero if VAL1 and VAL2 have the same contents. Note that |
487 | this function is different from value_equal; in C the operator == | |
488 | can return 0 even if the two values being compared are equal. */ | |
489 | ||
490 | int | |
491 | value_contents_equal (struct value *val1, struct value *val2) | |
492 | { | |
493 | struct type *type1; | |
494 | struct type *type2; | |
495 | int len; | |
496 | ||
497 | type1 = check_typedef (value_type (val1)); | |
498 | type2 = check_typedef (value_type (val2)); | |
499 | len = TYPE_LENGTH (type1); | |
500 | if (len != TYPE_LENGTH (type2)) | |
501 | return 0; | |
502 | ||
503 | return (memcmp (value_contents (val1), value_contents (val2), len) == 0); | |
504 | } | |
505 | ||
feb13ab0 AC |
506 | int |
507 | value_optimized_out (struct value *value) | |
508 | { | |
509 | return value->optimized_out; | |
510 | } | |
511 | ||
512 | void | |
513 | set_value_optimized_out (struct value *value, int val) | |
514 | { | |
515 | value->optimized_out = val; | |
516 | } | |
13c3b5f5 | 517 | |
0e03807e TT |
518 | int |
519 | value_entirely_optimized_out (const struct value *value) | |
520 | { | |
521 | if (!value->optimized_out) | |
522 | return 0; | |
523 | if (value->lval != lval_computed | |
ba19bb4d | 524 | || !value->location.computed.funcs->check_any_valid) |
0e03807e | 525 | return 1; |
b65c7efe | 526 | return !value->location.computed.funcs->check_any_valid (value); |
0e03807e TT |
527 | } |
528 | ||
529 | int | |
530 | value_bits_valid (const struct value *value, int offset, int length) | |
531 | { | |
532 | if (value == NULL || !value->optimized_out) | |
533 | return 1; | |
534 | if (value->lval != lval_computed | |
535 | || !value->location.computed.funcs->check_validity) | |
536 | return 0; | |
537 | return value->location.computed.funcs->check_validity (value, offset, | |
538 | length); | |
539 | } | |
540 | ||
8cf6f0b1 TT |
541 | int |
542 | value_bits_synthetic_pointer (const struct value *value, | |
543 | int offset, int length) | |
544 | { | |
545 | if (value == NULL || value->lval != lval_computed | |
546 | || !value->location.computed.funcs->check_synthetic_pointer) | |
547 | return 0; | |
548 | return value->location.computed.funcs->check_synthetic_pointer (value, | |
549 | offset, | |
550 | length); | |
551 | } | |
552 | ||
13c3b5f5 AC |
553 | int |
554 | value_embedded_offset (struct value *value) | |
555 | { | |
556 | return value->embedded_offset; | |
557 | } | |
558 | ||
559 | void | |
560 | set_value_embedded_offset (struct value *value, int val) | |
561 | { | |
562 | value->embedded_offset = val; | |
563 | } | |
b44d461b AC |
564 | |
565 | int | |
566 | value_pointed_to_offset (struct value *value) | |
567 | { | |
568 | return value->pointed_to_offset; | |
569 | } | |
570 | ||
571 | void | |
572 | set_value_pointed_to_offset (struct value *value, int val) | |
573 | { | |
574 | value->pointed_to_offset = val; | |
575 | } | |
13bb5560 | 576 | |
5f5233d4 PA |
577 | struct lval_funcs * |
578 | value_computed_funcs (struct value *v) | |
579 | { | |
580 | gdb_assert (VALUE_LVAL (v) == lval_computed); | |
581 | ||
582 | return v->location.computed.funcs; | |
583 | } | |
584 | ||
585 | void * | |
0e03807e | 586 | value_computed_closure (const struct value *v) |
5f5233d4 | 587 | { |
0e03807e | 588 | gdb_assert (v->lval == lval_computed); |
5f5233d4 PA |
589 | |
590 | return v->location.computed.closure; | |
591 | } | |
592 | ||
13bb5560 AC |
593 | enum lval_type * |
594 | deprecated_value_lval_hack (struct value *value) | |
595 | { | |
596 | return &value->lval; | |
597 | } | |
598 | ||
42ae5230 TT |
599 | CORE_ADDR |
600 | value_address (struct value *value) | |
601 | { | |
602 | if (value->lval == lval_internalvar | |
603 | || value->lval == lval_internalvar_component) | |
604 | return 0; | |
605 | return value->location.address + value->offset; | |
606 | } | |
607 | ||
608 | CORE_ADDR | |
609 | value_raw_address (struct value *value) | |
610 | { | |
611 | if (value->lval == lval_internalvar | |
612 | || value->lval == lval_internalvar_component) | |
613 | return 0; | |
614 | return value->location.address; | |
615 | } | |
616 | ||
617 | void | |
618 | set_value_address (struct value *value, CORE_ADDR addr) | |
13bb5560 | 619 | { |
42ae5230 TT |
620 | gdb_assert (value->lval != lval_internalvar |
621 | && value->lval != lval_internalvar_component); | |
622 | value->location.address = addr; | |
13bb5560 AC |
623 | } |
624 | ||
625 | struct internalvar ** | |
626 | deprecated_value_internalvar_hack (struct value *value) | |
627 | { | |
628 | return &value->location.internalvar; | |
629 | } | |
630 | ||
631 | struct frame_id * | |
632 | deprecated_value_frame_id_hack (struct value *value) | |
633 | { | |
634 | return &value->frame_id; | |
635 | } | |
636 | ||
637 | short * | |
638 | deprecated_value_regnum_hack (struct value *value) | |
639 | { | |
640 | return &value->regnum; | |
641 | } | |
88e3b34b AC |
642 | |
643 | int | |
644 | deprecated_value_modifiable (struct value *value) | |
645 | { | |
646 | return value->modifiable; | |
647 | } | |
648 | void | |
649 | deprecated_set_value_modifiable (struct value *value, int modifiable) | |
650 | { | |
651 | value->modifiable = modifiable; | |
652 | } | |
990a07ab | 653 | \f |
c906108c SS |
654 | /* Return a mark in the value chain. All values allocated after the |
655 | mark is obtained (except for those released) are subject to being freed | |
656 | if a subsequent value_free_to_mark is passed the mark. */ | |
f23631e4 | 657 | struct value * |
fba45db2 | 658 | value_mark (void) |
c906108c SS |
659 | { |
660 | return all_values; | |
661 | } | |
662 | ||
828d3400 DJ |
663 | /* Take a reference to VAL. VAL will not be deallocated until all |
664 | references are released. */ | |
665 | ||
666 | void | |
667 | value_incref (struct value *val) | |
668 | { | |
669 | val->reference_count++; | |
670 | } | |
671 | ||
672 | /* Release a reference to VAL, which was acquired with value_incref. | |
673 | This function is also called to deallocate values from the value | |
674 | chain. */ | |
675 | ||
3e3d7139 JG |
676 | void |
677 | value_free (struct value *val) | |
678 | { | |
679 | if (val) | |
5f5233d4 | 680 | { |
828d3400 DJ |
681 | gdb_assert (val->reference_count > 0); |
682 | val->reference_count--; | |
683 | if (val->reference_count > 0) | |
684 | return; | |
685 | ||
4ea48cc1 DJ |
686 | /* If there's an associated parent value, drop our reference to |
687 | it. */ | |
688 | if (val->parent != NULL) | |
689 | value_free (val->parent); | |
690 | ||
5f5233d4 PA |
691 | if (VALUE_LVAL (val) == lval_computed) |
692 | { | |
693 | struct lval_funcs *funcs = val->location.computed.funcs; | |
694 | ||
695 | if (funcs->free_closure) | |
696 | funcs->free_closure (val); | |
697 | } | |
698 | ||
699 | xfree (val->contents); | |
700 | } | |
3e3d7139 JG |
701 | xfree (val); |
702 | } | |
703 | ||
c906108c SS |
704 | /* Free all values allocated since MARK was obtained by value_mark |
705 | (except for those released). */ | |
706 | void | |
f23631e4 | 707 | value_free_to_mark (struct value *mark) |
c906108c | 708 | { |
f23631e4 AC |
709 | struct value *val; |
710 | struct value *next; | |
c906108c SS |
711 | |
712 | for (val = all_values; val && val != mark; val = next) | |
713 | { | |
df407dfe | 714 | next = val->next; |
c906108c SS |
715 | value_free (val); |
716 | } | |
717 | all_values = val; | |
718 | } | |
719 | ||
720 | /* Free all the values that have been allocated (except for those released). | |
725e88af DE |
721 | Call after each command, successful or not. |
722 | In practice this is called before each command, which is sufficient. */ | |
c906108c SS |
723 | |
724 | void | |
fba45db2 | 725 | free_all_values (void) |
c906108c | 726 | { |
f23631e4 AC |
727 | struct value *val; |
728 | struct value *next; | |
c906108c SS |
729 | |
730 | for (val = all_values; val; val = next) | |
731 | { | |
df407dfe | 732 | next = val->next; |
c906108c SS |
733 | value_free (val); |
734 | } | |
735 | ||
736 | all_values = 0; | |
737 | } | |
738 | ||
0cf6dd15 TJB |
739 | /* Frees all the elements in a chain of values. */ |
740 | ||
741 | void | |
742 | free_value_chain (struct value *v) | |
743 | { | |
744 | struct value *next; | |
745 | ||
746 | for (; v; v = next) | |
747 | { | |
748 | next = value_next (v); | |
749 | value_free (v); | |
750 | } | |
751 | } | |
752 | ||
c906108c SS |
753 | /* Remove VAL from the chain all_values |
754 | so it will not be freed automatically. */ | |
755 | ||
756 | void | |
f23631e4 | 757 | release_value (struct value *val) |
c906108c | 758 | { |
f23631e4 | 759 | struct value *v; |
c906108c SS |
760 | |
761 | if (all_values == val) | |
762 | { | |
763 | all_values = val->next; | |
06a64a0b | 764 | val->next = NULL; |
c906108c SS |
765 | return; |
766 | } | |
767 | ||
768 | for (v = all_values; v; v = v->next) | |
769 | { | |
770 | if (v->next == val) | |
771 | { | |
772 | v->next = val->next; | |
06a64a0b | 773 | val->next = NULL; |
c906108c SS |
774 | break; |
775 | } | |
776 | } | |
777 | } | |
778 | ||
779 | /* Release all values up to mark */ | |
f23631e4 AC |
780 | struct value * |
781 | value_release_to_mark (struct value *mark) | |
c906108c | 782 | { |
f23631e4 AC |
783 | struct value *val; |
784 | struct value *next; | |
c906108c | 785 | |
df407dfe AC |
786 | for (val = next = all_values; next; next = next->next) |
787 | if (next->next == mark) | |
c906108c | 788 | { |
df407dfe AC |
789 | all_values = next->next; |
790 | next->next = NULL; | |
c906108c SS |
791 | return val; |
792 | } | |
793 | all_values = 0; | |
794 | return val; | |
795 | } | |
796 | ||
797 | /* Return a copy of the value ARG. | |
798 | It contains the same contents, for same memory address, | |
799 | but it's a different block of storage. */ | |
800 | ||
f23631e4 AC |
801 | struct value * |
802 | value_copy (struct value *arg) | |
c906108c | 803 | { |
4754a64e | 804 | struct type *encl_type = value_enclosing_type (arg); |
3e3d7139 JG |
805 | struct value *val; |
806 | ||
807 | if (value_lazy (arg)) | |
808 | val = allocate_value_lazy (encl_type); | |
809 | else | |
810 | val = allocate_value (encl_type); | |
df407dfe | 811 | val->type = arg->type; |
c906108c | 812 | VALUE_LVAL (val) = VALUE_LVAL (arg); |
6f7c8fc2 | 813 | val->location = arg->location; |
df407dfe AC |
814 | val->offset = arg->offset; |
815 | val->bitpos = arg->bitpos; | |
816 | val->bitsize = arg->bitsize; | |
1df6926e | 817 | VALUE_FRAME_ID (val) = VALUE_FRAME_ID (arg); |
9ee8fc9d | 818 | VALUE_REGNUM (val) = VALUE_REGNUM (arg); |
d69fe07e | 819 | val->lazy = arg->lazy; |
feb13ab0 | 820 | val->optimized_out = arg->optimized_out; |
13c3b5f5 | 821 | val->embedded_offset = value_embedded_offset (arg); |
b44d461b | 822 | val->pointed_to_offset = arg->pointed_to_offset; |
c906108c | 823 | val->modifiable = arg->modifiable; |
d69fe07e | 824 | if (!value_lazy (val)) |
c906108c | 825 | { |
990a07ab | 826 | memcpy (value_contents_all_raw (val), value_contents_all_raw (arg), |
4754a64e | 827 | TYPE_LENGTH (value_enclosing_type (arg))); |
c906108c SS |
828 | |
829 | } | |
4ea48cc1 DJ |
830 | val->parent = arg->parent; |
831 | if (val->parent) | |
832 | value_incref (val->parent); | |
5f5233d4 PA |
833 | if (VALUE_LVAL (val) == lval_computed) |
834 | { | |
835 | struct lval_funcs *funcs = val->location.computed.funcs; | |
836 | ||
837 | if (funcs->copy_closure) | |
838 | val->location.computed.closure = funcs->copy_closure (val); | |
839 | } | |
c906108c SS |
840 | return val; |
841 | } | |
74bcbdf3 | 842 | |
c37f7098 KW |
843 | /* Return a version of ARG that is non-lvalue. */ |
844 | ||
845 | struct value * | |
846 | value_non_lval (struct value *arg) | |
847 | { | |
848 | if (VALUE_LVAL (arg) != not_lval) | |
849 | { | |
850 | struct type *enc_type = value_enclosing_type (arg); | |
851 | struct value *val = allocate_value (enc_type); | |
852 | ||
853 | memcpy (value_contents_all_raw (val), value_contents_all (arg), | |
854 | TYPE_LENGTH (enc_type)); | |
855 | val->type = arg->type; | |
856 | set_value_embedded_offset (val, value_embedded_offset (arg)); | |
857 | set_value_pointed_to_offset (val, value_pointed_to_offset (arg)); | |
858 | return val; | |
859 | } | |
860 | return arg; | |
861 | } | |
862 | ||
74bcbdf3 | 863 | void |
0e03807e TT |
864 | set_value_component_location (struct value *component, |
865 | const struct value *whole) | |
74bcbdf3 | 866 | { |
0e03807e | 867 | if (whole->lval == lval_internalvar) |
74bcbdf3 PA |
868 | VALUE_LVAL (component) = lval_internalvar_component; |
869 | else | |
0e03807e | 870 | VALUE_LVAL (component) = whole->lval; |
5f5233d4 | 871 | |
74bcbdf3 | 872 | component->location = whole->location; |
0e03807e | 873 | if (whole->lval == lval_computed) |
5f5233d4 PA |
874 | { |
875 | struct lval_funcs *funcs = whole->location.computed.funcs; | |
876 | ||
877 | if (funcs->copy_closure) | |
878 | component->location.computed.closure = funcs->copy_closure (whole); | |
879 | } | |
74bcbdf3 PA |
880 | } |
881 | ||
c906108c SS |
882 | \f |
883 | /* Access to the value history. */ | |
884 | ||
885 | /* Record a new value in the value history. | |
886 | Returns the absolute history index of the entry. | |
887 | Result of -1 indicates the value was not saved; otherwise it is the | |
888 | value history index of this new item. */ | |
889 | ||
890 | int | |
f23631e4 | 891 | record_latest_value (struct value *val) |
c906108c SS |
892 | { |
893 | int i; | |
894 | ||
895 | /* We don't want this value to have anything to do with the inferior anymore. | |
896 | In particular, "set $1 = 50" should not affect the variable from which | |
897 | the value was taken, and fast watchpoints should be able to assume that | |
898 | a value on the value history never changes. */ | |
d69fe07e | 899 | if (value_lazy (val)) |
c906108c SS |
900 | value_fetch_lazy (val); |
901 | /* We preserve VALUE_LVAL so that the user can find out where it was fetched | |
902 | from. This is a bit dubious, because then *&$1 does not just return $1 | |
903 | but the current contents of that location. c'est la vie... */ | |
904 | val->modifiable = 0; | |
905 | release_value (val); | |
906 | ||
907 | /* Here we treat value_history_count as origin-zero | |
908 | and applying to the value being stored now. */ | |
909 | ||
910 | i = value_history_count % VALUE_HISTORY_CHUNK; | |
911 | if (i == 0) | |
912 | { | |
f23631e4 | 913 | struct value_history_chunk *new |
a109c7c1 MS |
914 | = (struct value_history_chunk *) |
915 | ||
c5aa993b | 916 | xmalloc (sizeof (struct value_history_chunk)); |
c906108c SS |
917 | memset (new->values, 0, sizeof new->values); |
918 | new->next = value_history_chain; | |
919 | value_history_chain = new; | |
920 | } | |
921 | ||
922 | value_history_chain->values[i] = val; | |
923 | ||
924 | /* Now we regard value_history_count as origin-one | |
925 | and applying to the value just stored. */ | |
926 | ||
927 | return ++value_history_count; | |
928 | } | |
929 | ||
930 | /* Return a copy of the value in the history with sequence number NUM. */ | |
931 | ||
f23631e4 | 932 | struct value * |
fba45db2 | 933 | access_value_history (int num) |
c906108c | 934 | { |
f23631e4 | 935 | struct value_history_chunk *chunk; |
52f0bd74 AC |
936 | int i; |
937 | int absnum = num; | |
c906108c SS |
938 | |
939 | if (absnum <= 0) | |
940 | absnum += value_history_count; | |
941 | ||
942 | if (absnum <= 0) | |
943 | { | |
944 | if (num == 0) | |
8a3fe4f8 | 945 | error (_("The history is empty.")); |
c906108c | 946 | else if (num == 1) |
8a3fe4f8 | 947 | error (_("There is only one value in the history.")); |
c906108c | 948 | else |
8a3fe4f8 | 949 | error (_("History does not go back to $$%d."), -num); |
c906108c SS |
950 | } |
951 | if (absnum > value_history_count) | |
8a3fe4f8 | 952 | error (_("History has not yet reached $%d."), absnum); |
c906108c SS |
953 | |
954 | absnum--; | |
955 | ||
956 | /* Now absnum is always absolute and origin zero. */ | |
957 | ||
958 | chunk = value_history_chain; | |
959 | for (i = (value_history_count - 1) / VALUE_HISTORY_CHUNK - absnum / VALUE_HISTORY_CHUNK; | |
960 | i > 0; i--) | |
961 | chunk = chunk->next; | |
962 | ||
963 | return value_copy (chunk->values[absnum % VALUE_HISTORY_CHUNK]); | |
964 | } | |
965 | ||
c906108c | 966 | static void |
fba45db2 | 967 | show_values (char *num_exp, int from_tty) |
c906108c | 968 | { |
52f0bd74 | 969 | int i; |
f23631e4 | 970 | struct value *val; |
c906108c SS |
971 | static int num = 1; |
972 | ||
973 | if (num_exp) | |
974 | { | |
f132ba9d TJB |
975 | /* "show values +" should print from the stored position. |
976 | "show values <exp>" should print around value number <exp>. */ | |
c906108c | 977 | if (num_exp[0] != '+' || num_exp[1] != '\0') |
bb518678 | 978 | num = parse_and_eval_long (num_exp) - 5; |
c906108c SS |
979 | } |
980 | else | |
981 | { | |
f132ba9d | 982 | /* "show values" means print the last 10 values. */ |
c906108c SS |
983 | num = value_history_count - 9; |
984 | } | |
985 | ||
986 | if (num <= 0) | |
987 | num = 1; | |
988 | ||
989 | for (i = num; i < num + 10 && i <= value_history_count; i++) | |
990 | { | |
79a45b7d | 991 | struct value_print_options opts; |
a109c7c1 | 992 | |
c906108c | 993 | val = access_value_history (i); |
a3f17187 | 994 | printf_filtered (("$%d = "), i); |
79a45b7d TT |
995 | get_user_print_options (&opts); |
996 | value_print (val, gdb_stdout, &opts); | |
a3f17187 | 997 | printf_filtered (("\n")); |
c906108c SS |
998 | } |
999 | ||
f132ba9d | 1000 | /* The next "show values +" should start after what we just printed. */ |
c906108c SS |
1001 | num += 10; |
1002 | ||
1003 | /* Hitting just return after this command should do the same thing as | |
f132ba9d TJB |
1004 | "show values +". If num_exp is null, this is unnecessary, since |
1005 | "show values +" is not useful after "show values". */ | |
c906108c SS |
1006 | if (from_tty && num_exp) |
1007 | { | |
1008 | num_exp[0] = '+'; | |
1009 | num_exp[1] = '\0'; | |
1010 | } | |
1011 | } | |
1012 | \f | |
1013 | /* Internal variables. These are variables within the debugger | |
1014 | that hold values assigned by debugger commands. | |
1015 | The user refers to them with a '$' prefix | |
1016 | that does not appear in the variable names stored internally. */ | |
1017 | ||
4fa62494 UW |
1018 | struct internalvar |
1019 | { | |
1020 | struct internalvar *next; | |
1021 | char *name; | |
4fa62494 | 1022 | |
78267919 UW |
1023 | /* We support various different kinds of content of an internal variable. |
1024 | enum internalvar_kind specifies the kind, and union internalvar_data | |
1025 | provides the data associated with this particular kind. */ | |
1026 | ||
1027 | enum internalvar_kind | |
1028 | { | |
1029 | /* The internal variable is empty. */ | |
1030 | INTERNALVAR_VOID, | |
1031 | ||
1032 | /* The value of the internal variable is provided directly as | |
1033 | a GDB value object. */ | |
1034 | INTERNALVAR_VALUE, | |
1035 | ||
1036 | /* A fresh value is computed via a call-back routine on every | |
1037 | access to the internal variable. */ | |
1038 | INTERNALVAR_MAKE_VALUE, | |
4fa62494 | 1039 | |
78267919 UW |
1040 | /* The internal variable holds a GDB internal convenience function. */ |
1041 | INTERNALVAR_FUNCTION, | |
1042 | ||
cab0c772 UW |
1043 | /* The variable holds an integer value. */ |
1044 | INTERNALVAR_INTEGER, | |
1045 | ||
1046 | /* The variable holds a pointer value. */ | |
1047 | INTERNALVAR_POINTER, | |
78267919 UW |
1048 | |
1049 | /* The variable holds a GDB-provided string. */ | |
1050 | INTERNALVAR_STRING, | |
1051 | ||
1052 | } kind; | |
4fa62494 | 1053 | |
4fa62494 UW |
1054 | union internalvar_data |
1055 | { | |
78267919 UW |
1056 | /* A value object used with INTERNALVAR_VALUE. */ |
1057 | struct value *value; | |
1058 | ||
1059 | /* The call-back routine used with INTERNALVAR_MAKE_VALUE. */ | |
1060 | internalvar_make_value make_value; | |
1061 | ||
1062 | /* The internal function used with INTERNALVAR_FUNCTION. */ | |
1063 | struct | |
1064 | { | |
1065 | struct internal_function *function; | |
1066 | /* True if this is the canonical name for the function. */ | |
1067 | int canonical; | |
1068 | } fn; | |
1069 | ||
cab0c772 | 1070 | /* An integer value used with INTERNALVAR_INTEGER. */ |
78267919 UW |
1071 | struct |
1072 | { | |
1073 | /* If type is non-NULL, it will be used as the type to generate | |
1074 | a value for this internal variable. If type is NULL, a default | |
1075 | integer type for the architecture is used. */ | |
1076 | struct type *type; | |
cab0c772 UW |
1077 | LONGEST val; |
1078 | } integer; | |
1079 | ||
1080 | /* A pointer value used with INTERNALVAR_POINTER. */ | |
1081 | struct | |
1082 | { | |
1083 | struct type *type; | |
1084 | CORE_ADDR val; | |
1085 | } pointer; | |
78267919 UW |
1086 | |
1087 | /* A string value used with INTERNALVAR_STRING. */ | |
1088 | char *string; | |
4fa62494 UW |
1089 | } u; |
1090 | }; | |
1091 | ||
c906108c SS |
1092 | static struct internalvar *internalvars; |
1093 | ||
53e5f3cf AS |
1094 | /* If the variable does not already exist create it and give it the value given. |
1095 | If no value is given then the default is zero. */ | |
1096 | static void | |
1097 | init_if_undefined_command (char* args, int from_tty) | |
1098 | { | |
1099 | struct internalvar* intvar; | |
1100 | ||
1101 | /* Parse the expression - this is taken from set_command(). */ | |
1102 | struct expression *expr = parse_expression (args); | |
1103 | register struct cleanup *old_chain = | |
1104 | make_cleanup (free_current_contents, &expr); | |
1105 | ||
1106 | /* Validate the expression. | |
1107 | Was the expression an assignment? | |
1108 | Or even an expression at all? */ | |
1109 | if (expr->nelts == 0 || expr->elts[0].opcode != BINOP_ASSIGN) | |
1110 | error (_("Init-if-undefined requires an assignment expression.")); | |
1111 | ||
1112 | /* Extract the variable from the parsed expression. | |
1113 | In the case of an assign the lvalue will be in elts[1] and elts[2]. */ | |
1114 | if (expr->elts[1].opcode != OP_INTERNALVAR) | |
1115 | error (_("The first parameter to init-if-undefined should be a GDB variable.")); | |
1116 | intvar = expr->elts[2].internalvar; | |
1117 | ||
1118 | /* Only evaluate the expression if the lvalue is void. | |
1119 | This may still fail if the expresssion is invalid. */ | |
78267919 | 1120 | if (intvar->kind == INTERNALVAR_VOID) |
53e5f3cf AS |
1121 | evaluate_expression (expr); |
1122 | ||
1123 | do_cleanups (old_chain); | |
1124 | } | |
1125 | ||
1126 | ||
c906108c SS |
1127 | /* Look up an internal variable with name NAME. NAME should not |
1128 | normally include a dollar sign. | |
1129 | ||
1130 | If the specified internal variable does not exist, | |
c4a3d09a | 1131 | the return value is NULL. */ |
c906108c SS |
1132 | |
1133 | struct internalvar * | |
bc3b79fd | 1134 | lookup_only_internalvar (const char *name) |
c906108c | 1135 | { |
52f0bd74 | 1136 | struct internalvar *var; |
c906108c SS |
1137 | |
1138 | for (var = internalvars; var; var = var->next) | |
5cb316ef | 1139 | if (strcmp (var->name, name) == 0) |
c906108c SS |
1140 | return var; |
1141 | ||
c4a3d09a MF |
1142 | return NULL; |
1143 | } | |
1144 | ||
1145 | ||
1146 | /* Create an internal variable with name NAME and with a void value. | |
1147 | NAME should not normally include a dollar sign. */ | |
1148 | ||
1149 | struct internalvar * | |
bc3b79fd | 1150 | create_internalvar (const char *name) |
c4a3d09a MF |
1151 | { |
1152 | struct internalvar *var; | |
a109c7c1 | 1153 | |
c906108c | 1154 | var = (struct internalvar *) xmalloc (sizeof (struct internalvar)); |
1754f103 | 1155 | var->name = concat (name, (char *)NULL); |
78267919 | 1156 | var->kind = INTERNALVAR_VOID; |
c906108c SS |
1157 | var->next = internalvars; |
1158 | internalvars = var; | |
1159 | return var; | |
1160 | } | |
1161 | ||
4aa995e1 PA |
1162 | /* Create an internal variable with name NAME and register FUN as the |
1163 | function that value_of_internalvar uses to create a value whenever | |
1164 | this variable is referenced. NAME should not normally include a | |
1165 | dollar sign. */ | |
1166 | ||
1167 | struct internalvar * | |
1168 | create_internalvar_type_lazy (char *name, internalvar_make_value fun) | |
1169 | { | |
4fa62494 | 1170 | struct internalvar *var = create_internalvar (name); |
a109c7c1 | 1171 | |
78267919 UW |
1172 | var->kind = INTERNALVAR_MAKE_VALUE; |
1173 | var->u.make_value = fun; | |
4aa995e1 PA |
1174 | return var; |
1175 | } | |
c4a3d09a MF |
1176 | |
1177 | /* Look up an internal variable with name NAME. NAME should not | |
1178 | normally include a dollar sign. | |
1179 | ||
1180 | If the specified internal variable does not exist, | |
1181 | one is created, with a void value. */ | |
1182 | ||
1183 | struct internalvar * | |
bc3b79fd | 1184 | lookup_internalvar (const char *name) |
c4a3d09a MF |
1185 | { |
1186 | struct internalvar *var; | |
1187 | ||
1188 | var = lookup_only_internalvar (name); | |
1189 | if (var) | |
1190 | return var; | |
1191 | ||
1192 | return create_internalvar (name); | |
1193 | } | |
1194 | ||
78267919 UW |
1195 | /* Return current value of internal variable VAR. For variables that |
1196 | are not inherently typed, use a value type appropriate for GDBARCH. */ | |
1197 | ||
f23631e4 | 1198 | struct value * |
78267919 | 1199 | value_of_internalvar (struct gdbarch *gdbarch, struct internalvar *var) |
c906108c | 1200 | { |
f23631e4 | 1201 | struct value *val; |
0914bcdb SS |
1202 | struct trace_state_variable *tsv; |
1203 | ||
1204 | /* If there is a trace state variable of the same name, assume that | |
1205 | is what we really want to see. */ | |
1206 | tsv = find_trace_state_variable (var->name); | |
1207 | if (tsv) | |
1208 | { | |
1209 | tsv->value_known = target_get_trace_state_variable_value (tsv->number, | |
1210 | &(tsv->value)); | |
1211 | if (tsv->value_known) | |
1212 | val = value_from_longest (builtin_type (gdbarch)->builtin_int64, | |
1213 | tsv->value); | |
1214 | else | |
1215 | val = allocate_value (builtin_type (gdbarch)->builtin_void); | |
1216 | return val; | |
1217 | } | |
c906108c | 1218 | |
78267919 | 1219 | switch (var->kind) |
5f5233d4 | 1220 | { |
78267919 UW |
1221 | case INTERNALVAR_VOID: |
1222 | val = allocate_value (builtin_type (gdbarch)->builtin_void); | |
1223 | break; | |
4fa62494 | 1224 | |
78267919 UW |
1225 | case INTERNALVAR_FUNCTION: |
1226 | val = allocate_value (builtin_type (gdbarch)->internal_fn); | |
1227 | break; | |
4fa62494 | 1228 | |
cab0c772 UW |
1229 | case INTERNALVAR_INTEGER: |
1230 | if (!var->u.integer.type) | |
78267919 | 1231 | val = value_from_longest (builtin_type (gdbarch)->builtin_int, |
cab0c772 | 1232 | var->u.integer.val); |
78267919 | 1233 | else |
cab0c772 UW |
1234 | val = value_from_longest (var->u.integer.type, var->u.integer.val); |
1235 | break; | |
1236 | ||
1237 | case INTERNALVAR_POINTER: | |
1238 | val = value_from_pointer (var->u.pointer.type, var->u.pointer.val); | |
78267919 | 1239 | break; |
4fa62494 | 1240 | |
78267919 UW |
1241 | case INTERNALVAR_STRING: |
1242 | val = value_cstring (var->u.string, strlen (var->u.string), | |
1243 | builtin_type (gdbarch)->builtin_char); | |
1244 | break; | |
4fa62494 | 1245 | |
78267919 UW |
1246 | case INTERNALVAR_VALUE: |
1247 | val = value_copy (var->u.value); | |
4aa995e1 PA |
1248 | if (value_lazy (val)) |
1249 | value_fetch_lazy (val); | |
78267919 | 1250 | break; |
4aa995e1 | 1251 | |
78267919 UW |
1252 | case INTERNALVAR_MAKE_VALUE: |
1253 | val = (*var->u.make_value) (gdbarch, var); | |
1254 | break; | |
1255 | ||
1256 | default: | |
1257 | internal_error (__FILE__, __LINE__, "bad kind"); | |
1258 | } | |
1259 | ||
1260 | /* Change the VALUE_LVAL to lval_internalvar so that future operations | |
1261 | on this value go back to affect the original internal variable. | |
1262 | ||
1263 | Do not do this for INTERNALVAR_MAKE_VALUE variables, as those have | |
1264 | no underlying modifyable state in the internal variable. | |
1265 | ||
1266 | Likewise, if the variable's value is a computed lvalue, we want | |
1267 | references to it to produce another computed lvalue, where | |
1268 | references and assignments actually operate through the | |
1269 | computed value's functions. | |
1270 | ||
1271 | This means that internal variables with computed values | |
1272 | behave a little differently from other internal variables: | |
1273 | assignments to them don't just replace the previous value | |
1274 | altogether. At the moment, this seems like the behavior we | |
1275 | want. */ | |
1276 | ||
1277 | if (var->kind != INTERNALVAR_MAKE_VALUE | |
1278 | && val->lval != lval_computed) | |
1279 | { | |
1280 | VALUE_LVAL (val) = lval_internalvar; | |
1281 | VALUE_INTERNALVAR (val) = var; | |
5f5233d4 | 1282 | } |
d3c139e9 | 1283 | |
4fa62494 UW |
1284 | return val; |
1285 | } | |
d3c139e9 | 1286 | |
4fa62494 UW |
1287 | int |
1288 | get_internalvar_integer (struct internalvar *var, LONGEST *result) | |
1289 | { | |
78267919 | 1290 | switch (var->kind) |
4fa62494 | 1291 | { |
cab0c772 UW |
1292 | case INTERNALVAR_INTEGER: |
1293 | *result = var->u.integer.val; | |
1294 | return 1; | |
d3c139e9 | 1295 | |
4fa62494 UW |
1296 | default: |
1297 | return 0; | |
1298 | } | |
1299 | } | |
d3c139e9 | 1300 | |
4fa62494 UW |
1301 | static int |
1302 | get_internalvar_function (struct internalvar *var, | |
1303 | struct internal_function **result) | |
1304 | { | |
78267919 | 1305 | switch (var->kind) |
d3c139e9 | 1306 | { |
78267919 UW |
1307 | case INTERNALVAR_FUNCTION: |
1308 | *result = var->u.fn.function; | |
4fa62494 | 1309 | return 1; |
d3c139e9 | 1310 | |
4fa62494 UW |
1311 | default: |
1312 | return 0; | |
1313 | } | |
c906108c SS |
1314 | } |
1315 | ||
1316 | void | |
fba45db2 | 1317 | set_internalvar_component (struct internalvar *var, int offset, int bitpos, |
f23631e4 | 1318 | int bitsize, struct value *newval) |
c906108c | 1319 | { |
4fa62494 | 1320 | gdb_byte *addr; |
c906108c | 1321 | |
78267919 | 1322 | switch (var->kind) |
4fa62494 | 1323 | { |
78267919 UW |
1324 | case INTERNALVAR_VALUE: |
1325 | addr = value_contents_writeable (var->u.value); | |
4fa62494 UW |
1326 | |
1327 | if (bitsize) | |
50810684 | 1328 | modify_field (value_type (var->u.value), addr + offset, |
4fa62494 UW |
1329 | value_as_long (newval), bitpos, bitsize); |
1330 | else | |
1331 | memcpy (addr + offset, value_contents (newval), | |
1332 | TYPE_LENGTH (value_type (newval))); | |
1333 | break; | |
78267919 UW |
1334 | |
1335 | default: | |
1336 | /* We can never get a component of any other kind. */ | |
1337 | internal_error (__FILE__, __LINE__, "set_internalvar_component"); | |
4fa62494 | 1338 | } |
c906108c SS |
1339 | } |
1340 | ||
1341 | void | |
f23631e4 | 1342 | set_internalvar (struct internalvar *var, struct value *val) |
c906108c | 1343 | { |
78267919 | 1344 | enum internalvar_kind new_kind; |
4fa62494 | 1345 | union internalvar_data new_data = { 0 }; |
c906108c | 1346 | |
78267919 | 1347 | if (var->kind == INTERNALVAR_FUNCTION && var->u.fn.canonical) |
bc3b79fd TJB |
1348 | error (_("Cannot overwrite convenience function %s"), var->name); |
1349 | ||
4fa62494 | 1350 | /* Prepare new contents. */ |
78267919 | 1351 | switch (TYPE_CODE (check_typedef (value_type (val)))) |
4fa62494 UW |
1352 | { |
1353 | case TYPE_CODE_VOID: | |
78267919 | 1354 | new_kind = INTERNALVAR_VOID; |
4fa62494 UW |
1355 | break; |
1356 | ||
1357 | case TYPE_CODE_INTERNAL_FUNCTION: | |
1358 | gdb_assert (VALUE_LVAL (val) == lval_internalvar); | |
78267919 UW |
1359 | new_kind = INTERNALVAR_FUNCTION; |
1360 | get_internalvar_function (VALUE_INTERNALVAR (val), | |
1361 | &new_data.fn.function); | |
1362 | /* Copies created here are never canonical. */ | |
4fa62494 UW |
1363 | break; |
1364 | ||
1365 | case TYPE_CODE_INT: | |
cab0c772 UW |
1366 | new_kind = INTERNALVAR_INTEGER; |
1367 | new_data.integer.type = value_type (val); | |
1368 | new_data.integer.val = value_as_long (val); | |
4fa62494 UW |
1369 | break; |
1370 | ||
1371 | case TYPE_CODE_PTR: | |
cab0c772 UW |
1372 | new_kind = INTERNALVAR_POINTER; |
1373 | new_data.pointer.type = value_type (val); | |
1374 | new_data.pointer.val = value_as_address (val); | |
4fa62494 UW |
1375 | break; |
1376 | ||
1377 | default: | |
78267919 UW |
1378 | new_kind = INTERNALVAR_VALUE; |
1379 | new_data.value = value_copy (val); | |
1380 | new_data.value->modifiable = 1; | |
4fa62494 UW |
1381 | |
1382 | /* Force the value to be fetched from the target now, to avoid problems | |
1383 | later when this internalvar is referenced and the target is gone or | |
1384 | has changed. */ | |
78267919 UW |
1385 | if (value_lazy (new_data.value)) |
1386 | value_fetch_lazy (new_data.value); | |
4fa62494 UW |
1387 | |
1388 | /* Release the value from the value chain to prevent it from being | |
1389 | deleted by free_all_values. From here on this function should not | |
1390 | call error () until new_data is installed into the var->u to avoid | |
1391 | leaking memory. */ | |
78267919 | 1392 | release_value (new_data.value); |
4fa62494 UW |
1393 | break; |
1394 | } | |
1395 | ||
1396 | /* Clean up old contents. */ | |
1397 | clear_internalvar (var); | |
1398 | ||
1399 | /* Switch over. */ | |
78267919 | 1400 | var->kind = new_kind; |
4fa62494 | 1401 | var->u = new_data; |
c906108c SS |
1402 | /* End code which must not call error(). */ |
1403 | } | |
1404 | ||
4fa62494 UW |
1405 | void |
1406 | set_internalvar_integer (struct internalvar *var, LONGEST l) | |
1407 | { | |
1408 | /* Clean up old contents. */ | |
1409 | clear_internalvar (var); | |
1410 | ||
cab0c772 UW |
1411 | var->kind = INTERNALVAR_INTEGER; |
1412 | var->u.integer.type = NULL; | |
1413 | var->u.integer.val = l; | |
78267919 UW |
1414 | } |
1415 | ||
1416 | void | |
1417 | set_internalvar_string (struct internalvar *var, const char *string) | |
1418 | { | |
1419 | /* Clean up old contents. */ | |
1420 | clear_internalvar (var); | |
1421 | ||
1422 | var->kind = INTERNALVAR_STRING; | |
1423 | var->u.string = xstrdup (string); | |
4fa62494 UW |
1424 | } |
1425 | ||
1426 | static void | |
1427 | set_internalvar_function (struct internalvar *var, struct internal_function *f) | |
1428 | { | |
1429 | /* Clean up old contents. */ | |
1430 | clear_internalvar (var); | |
1431 | ||
78267919 UW |
1432 | var->kind = INTERNALVAR_FUNCTION; |
1433 | var->u.fn.function = f; | |
1434 | var->u.fn.canonical = 1; | |
1435 | /* Variables installed here are always the canonical version. */ | |
4fa62494 UW |
1436 | } |
1437 | ||
1438 | void | |
1439 | clear_internalvar (struct internalvar *var) | |
1440 | { | |
1441 | /* Clean up old contents. */ | |
78267919 | 1442 | switch (var->kind) |
4fa62494 | 1443 | { |
78267919 UW |
1444 | case INTERNALVAR_VALUE: |
1445 | value_free (var->u.value); | |
1446 | break; | |
1447 | ||
1448 | case INTERNALVAR_STRING: | |
1449 | xfree (var->u.string); | |
4fa62494 UW |
1450 | break; |
1451 | ||
1452 | default: | |
4fa62494 UW |
1453 | break; |
1454 | } | |
1455 | ||
78267919 UW |
1456 | /* Reset to void kind. */ |
1457 | var->kind = INTERNALVAR_VOID; | |
4fa62494 UW |
1458 | } |
1459 | ||
c906108c | 1460 | char * |
fba45db2 | 1461 | internalvar_name (struct internalvar *var) |
c906108c SS |
1462 | { |
1463 | return var->name; | |
1464 | } | |
1465 | ||
4fa62494 UW |
1466 | static struct internal_function * |
1467 | create_internal_function (const char *name, | |
1468 | internal_function_fn handler, void *cookie) | |
bc3b79fd | 1469 | { |
bc3b79fd | 1470 | struct internal_function *ifn = XNEW (struct internal_function); |
a109c7c1 | 1471 | |
bc3b79fd TJB |
1472 | ifn->name = xstrdup (name); |
1473 | ifn->handler = handler; | |
1474 | ifn->cookie = cookie; | |
4fa62494 | 1475 | return ifn; |
bc3b79fd TJB |
1476 | } |
1477 | ||
1478 | char * | |
1479 | value_internal_function_name (struct value *val) | |
1480 | { | |
4fa62494 UW |
1481 | struct internal_function *ifn; |
1482 | int result; | |
1483 | ||
1484 | gdb_assert (VALUE_LVAL (val) == lval_internalvar); | |
1485 | result = get_internalvar_function (VALUE_INTERNALVAR (val), &ifn); | |
1486 | gdb_assert (result); | |
1487 | ||
bc3b79fd TJB |
1488 | return ifn->name; |
1489 | } | |
1490 | ||
1491 | struct value * | |
d452c4bc UW |
1492 | call_internal_function (struct gdbarch *gdbarch, |
1493 | const struct language_defn *language, | |
1494 | struct value *func, int argc, struct value **argv) | |
bc3b79fd | 1495 | { |
4fa62494 UW |
1496 | struct internal_function *ifn; |
1497 | int result; | |
1498 | ||
1499 | gdb_assert (VALUE_LVAL (func) == lval_internalvar); | |
1500 | result = get_internalvar_function (VALUE_INTERNALVAR (func), &ifn); | |
1501 | gdb_assert (result); | |
1502 | ||
d452c4bc | 1503 | return (*ifn->handler) (gdbarch, language, ifn->cookie, argc, argv); |
bc3b79fd TJB |
1504 | } |
1505 | ||
1506 | /* The 'function' command. This does nothing -- it is just a | |
1507 | placeholder to let "help function NAME" work. This is also used as | |
1508 | the implementation of the sub-command that is created when | |
1509 | registering an internal function. */ | |
1510 | static void | |
1511 | function_command (char *command, int from_tty) | |
1512 | { | |
1513 | /* Do nothing. */ | |
1514 | } | |
1515 | ||
1516 | /* Clean up if an internal function's command is destroyed. */ | |
1517 | static void | |
1518 | function_destroyer (struct cmd_list_element *self, void *ignore) | |
1519 | { | |
1520 | xfree (self->name); | |
1521 | xfree (self->doc); | |
1522 | } | |
1523 | ||
1524 | /* Add a new internal function. NAME is the name of the function; DOC | |
1525 | is a documentation string describing the function. HANDLER is | |
1526 | called when the function is invoked. COOKIE is an arbitrary | |
1527 | pointer which is passed to HANDLER and is intended for "user | |
1528 | data". */ | |
1529 | void | |
1530 | add_internal_function (const char *name, const char *doc, | |
1531 | internal_function_fn handler, void *cookie) | |
1532 | { | |
1533 | struct cmd_list_element *cmd; | |
4fa62494 | 1534 | struct internal_function *ifn; |
bc3b79fd | 1535 | struct internalvar *var = lookup_internalvar (name); |
4fa62494 UW |
1536 | |
1537 | ifn = create_internal_function (name, handler, cookie); | |
1538 | set_internalvar_function (var, ifn); | |
bc3b79fd TJB |
1539 | |
1540 | cmd = add_cmd (xstrdup (name), no_class, function_command, (char *) doc, | |
1541 | &functionlist); | |
1542 | cmd->destroyer = function_destroyer; | |
1543 | } | |
1544 | ||
ae5a43e0 DJ |
1545 | /* Update VALUE before discarding OBJFILE. COPIED_TYPES is used to |
1546 | prevent cycles / duplicates. */ | |
1547 | ||
4e7a5ef5 | 1548 | void |
ae5a43e0 DJ |
1549 | preserve_one_value (struct value *value, struct objfile *objfile, |
1550 | htab_t copied_types) | |
1551 | { | |
1552 | if (TYPE_OBJFILE (value->type) == objfile) | |
1553 | value->type = copy_type_recursive (objfile, value->type, copied_types); | |
1554 | ||
1555 | if (TYPE_OBJFILE (value->enclosing_type) == objfile) | |
1556 | value->enclosing_type = copy_type_recursive (objfile, | |
1557 | value->enclosing_type, | |
1558 | copied_types); | |
1559 | } | |
1560 | ||
78267919 UW |
1561 | /* Likewise for internal variable VAR. */ |
1562 | ||
1563 | static void | |
1564 | preserve_one_internalvar (struct internalvar *var, struct objfile *objfile, | |
1565 | htab_t copied_types) | |
1566 | { | |
1567 | switch (var->kind) | |
1568 | { | |
cab0c772 UW |
1569 | case INTERNALVAR_INTEGER: |
1570 | if (var->u.integer.type && TYPE_OBJFILE (var->u.integer.type) == objfile) | |
1571 | var->u.integer.type | |
1572 | = copy_type_recursive (objfile, var->u.integer.type, copied_types); | |
1573 | break; | |
1574 | ||
1575 | case INTERNALVAR_POINTER: | |
1576 | if (TYPE_OBJFILE (var->u.pointer.type) == objfile) | |
1577 | var->u.pointer.type | |
1578 | = copy_type_recursive (objfile, var->u.pointer.type, copied_types); | |
78267919 UW |
1579 | break; |
1580 | ||
1581 | case INTERNALVAR_VALUE: | |
1582 | preserve_one_value (var->u.value, objfile, copied_types); | |
1583 | break; | |
1584 | } | |
1585 | } | |
1586 | ||
ae5a43e0 DJ |
1587 | /* Update the internal variables and value history when OBJFILE is |
1588 | discarded; we must copy the types out of the objfile. New global types | |
1589 | will be created for every convenience variable which currently points to | |
1590 | this objfile's types, and the convenience variables will be adjusted to | |
1591 | use the new global types. */ | |
c906108c SS |
1592 | |
1593 | void | |
ae5a43e0 | 1594 | preserve_values (struct objfile *objfile) |
c906108c | 1595 | { |
ae5a43e0 DJ |
1596 | htab_t copied_types; |
1597 | struct value_history_chunk *cur; | |
52f0bd74 | 1598 | struct internalvar *var; |
ae5a43e0 | 1599 | int i; |
c906108c | 1600 | |
ae5a43e0 DJ |
1601 | /* Create the hash table. We allocate on the objfile's obstack, since |
1602 | it is soon to be deleted. */ | |
1603 | copied_types = create_copied_types_hash (objfile); | |
1604 | ||
1605 | for (cur = value_history_chain; cur; cur = cur->next) | |
1606 | for (i = 0; i < VALUE_HISTORY_CHUNK; i++) | |
1607 | if (cur->values[i]) | |
1608 | preserve_one_value (cur->values[i], objfile, copied_types); | |
1609 | ||
1610 | for (var = internalvars; var; var = var->next) | |
78267919 | 1611 | preserve_one_internalvar (var, objfile, copied_types); |
ae5a43e0 | 1612 | |
4e7a5ef5 | 1613 | preserve_python_values (objfile, copied_types); |
a08702d6 | 1614 | |
ae5a43e0 | 1615 | htab_delete (copied_types); |
c906108c SS |
1616 | } |
1617 | ||
1618 | static void | |
fba45db2 | 1619 | show_convenience (char *ignore, int from_tty) |
c906108c | 1620 | { |
e17c207e | 1621 | struct gdbarch *gdbarch = get_current_arch (); |
52f0bd74 | 1622 | struct internalvar *var; |
c906108c | 1623 | int varseen = 0; |
79a45b7d | 1624 | struct value_print_options opts; |
c906108c | 1625 | |
79a45b7d | 1626 | get_user_print_options (&opts); |
c906108c SS |
1627 | for (var = internalvars; var; var = var->next) |
1628 | { | |
c906108c SS |
1629 | if (!varseen) |
1630 | { | |
1631 | varseen = 1; | |
1632 | } | |
a3f17187 | 1633 | printf_filtered (("$%s = "), var->name); |
78267919 | 1634 | value_print (value_of_internalvar (gdbarch, var), gdb_stdout, |
79a45b7d | 1635 | &opts); |
a3f17187 | 1636 | printf_filtered (("\n")); |
c906108c SS |
1637 | } |
1638 | if (!varseen) | |
a3f17187 AC |
1639 | printf_unfiltered (_("\ |
1640 | No debugger convenience variables now defined.\n\ | |
c906108c | 1641 | Convenience variables have names starting with \"$\";\n\ |
a3f17187 | 1642 | use \"set\" as in \"set $foo = 5\" to define them.\n")); |
c906108c SS |
1643 | } |
1644 | \f | |
1645 | /* Extract a value as a C number (either long or double). | |
1646 | Knows how to convert fixed values to double, or | |
1647 | floating values to long. | |
1648 | Does not deallocate the value. */ | |
1649 | ||
1650 | LONGEST | |
f23631e4 | 1651 | value_as_long (struct value *val) |
c906108c SS |
1652 | { |
1653 | /* This coerces arrays and functions, which is necessary (e.g. | |
1654 | in disassemble_command). It also dereferences references, which | |
1655 | I suspect is the most logical thing to do. */ | |
994b9211 | 1656 | val = coerce_array (val); |
0fd88904 | 1657 | return unpack_long (value_type (val), value_contents (val)); |
c906108c SS |
1658 | } |
1659 | ||
1660 | DOUBLEST | |
f23631e4 | 1661 | value_as_double (struct value *val) |
c906108c SS |
1662 | { |
1663 | DOUBLEST foo; | |
1664 | int inv; | |
c5aa993b | 1665 | |
0fd88904 | 1666 | foo = unpack_double (value_type (val), value_contents (val), &inv); |
c906108c | 1667 | if (inv) |
8a3fe4f8 | 1668 | error (_("Invalid floating value found in program.")); |
c906108c SS |
1669 | return foo; |
1670 | } | |
4ef30785 | 1671 | |
4478b372 JB |
1672 | /* Extract a value as a C pointer. Does not deallocate the value. |
1673 | Note that val's type may not actually be a pointer; value_as_long | |
1674 | handles all the cases. */ | |
c906108c | 1675 | CORE_ADDR |
f23631e4 | 1676 | value_as_address (struct value *val) |
c906108c | 1677 | { |
50810684 UW |
1678 | struct gdbarch *gdbarch = get_type_arch (value_type (val)); |
1679 | ||
c906108c SS |
1680 | /* Assume a CORE_ADDR can fit in a LONGEST (for now). Not sure |
1681 | whether we want this to be true eventually. */ | |
1682 | #if 0 | |
bf6ae464 | 1683 | /* gdbarch_addr_bits_remove is wrong if we are being called for a |
c906108c SS |
1684 | non-address (e.g. argument to "signal", "info break", etc.), or |
1685 | for pointers to char, in which the low bits *are* significant. */ | |
50810684 | 1686 | return gdbarch_addr_bits_remove (gdbarch, value_as_long (val)); |
c906108c | 1687 | #else |
f312f057 JB |
1688 | |
1689 | /* There are several targets (IA-64, PowerPC, and others) which | |
1690 | don't represent pointers to functions as simply the address of | |
1691 | the function's entry point. For example, on the IA-64, a | |
1692 | function pointer points to a two-word descriptor, generated by | |
1693 | the linker, which contains the function's entry point, and the | |
1694 | value the IA-64 "global pointer" register should have --- to | |
1695 | support position-independent code. The linker generates | |
1696 | descriptors only for those functions whose addresses are taken. | |
1697 | ||
1698 | On such targets, it's difficult for GDB to convert an arbitrary | |
1699 | function address into a function pointer; it has to either find | |
1700 | an existing descriptor for that function, or call malloc and | |
1701 | build its own. On some targets, it is impossible for GDB to | |
1702 | build a descriptor at all: the descriptor must contain a jump | |
1703 | instruction; data memory cannot be executed; and code memory | |
1704 | cannot be modified. | |
1705 | ||
1706 | Upon entry to this function, if VAL is a value of type `function' | |
1707 | (that is, TYPE_CODE (VALUE_TYPE (val)) == TYPE_CODE_FUNC), then | |
42ae5230 | 1708 | value_address (val) is the address of the function. This is what |
f312f057 JB |
1709 | you'll get if you evaluate an expression like `main'. The call |
1710 | to COERCE_ARRAY below actually does all the usual unary | |
1711 | conversions, which includes converting values of type `function' | |
1712 | to `pointer to function'. This is the challenging conversion | |
1713 | discussed above. Then, `unpack_long' will convert that pointer | |
1714 | back into an address. | |
1715 | ||
1716 | So, suppose the user types `disassemble foo' on an architecture | |
1717 | with a strange function pointer representation, on which GDB | |
1718 | cannot build its own descriptors, and suppose further that `foo' | |
1719 | has no linker-built descriptor. The address->pointer conversion | |
1720 | will signal an error and prevent the command from running, even | |
1721 | though the next step would have been to convert the pointer | |
1722 | directly back into the same address. | |
1723 | ||
1724 | The following shortcut avoids this whole mess. If VAL is a | |
1725 | function, just return its address directly. */ | |
df407dfe AC |
1726 | if (TYPE_CODE (value_type (val)) == TYPE_CODE_FUNC |
1727 | || TYPE_CODE (value_type (val)) == TYPE_CODE_METHOD) | |
42ae5230 | 1728 | return value_address (val); |
f312f057 | 1729 | |
994b9211 | 1730 | val = coerce_array (val); |
fc0c74b1 AC |
1731 | |
1732 | /* Some architectures (e.g. Harvard), map instruction and data | |
1733 | addresses onto a single large unified address space. For | |
1734 | instance: An architecture may consider a large integer in the | |
1735 | range 0x10000000 .. 0x1000ffff to already represent a data | |
1736 | addresses (hence not need a pointer to address conversion) while | |
1737 | a small integer would still need to be converted integer to | |
1738 | pointer to address. Just assume such architectures handle all | |
1739 | integer conversions in a single function. */ | |
1740 | ||
1741 | /* JimB writes: | |
1742 | ||
1743 | I think INTEGER_TO_ADDRESS is a good idea as proposed --- but we | |
1744 | must admonish GDB hackers to make sure its behavior matches the | |
1745 | compiler's, whenever possible. | |
1746 | ||
1747 | In general, I think GDB should evaluate expressions the same way | |
1748 | the compiler does. When the user copies an expression out of | |
1749 | their source code and hands it to a `print' command, they should | |
1750 | get the same value the compiler would have computed. Any | |
1751 | deviation from this rule can cause major confusion and annoyance, | |
1752 | and needs to be justified carefully. In other words, GDB doesn't | |
1753 | really have the freedom to do these conversions in clever and | |
1754 | useful ways. | |
1755 | ||
1756 | AndrewC pointed out that users aren't complaining about how GDB | |
1757 | casts integers to pointers; they are complaining that they can't | |
1758 | take an address from a disassembly listing and give it to `x/i'. | |
1759 | This is certainly important. | |
1760 | ||
79dd2d24 | 1761 | Adding an architecture method like integer_to_address() certainly |
fc0c74b1 AC |
1762 | makes it possible for GDB to "get it right" in all circumstances |
1763 | --- the target has complete control over how things get done, so | |
1764 | people can Do The Right Thing for their target without breaking | |
1765 | anyone else. The standard doesn't specify how integers get | |
1766 | converted to pointers; usually, the ABI doesn't either, but | |
1767 | ABI-specific code is a more reasonable place to handle it. */ | |
1768 | ||
df407dfe AC |
1769 | if (TYPE_CODE (value_type (val)) != TYPE_CODE_PTR |
1770 | && TYPE_CODE (value_type (val)) != TYPE_CODE_REF | |
50810684 UW |
1771 | && gdbarch_integer_to_address_p (gdbarch)) |
1772 | return gdbarch_integer_to_address (gdbarch, value_type (val), | |
0fd88904 | 1773 | value_contents (val)); |
fc0c74b1 | 1774 | |
0fd88904 | 1775 | return unpack_long (value_type (val), value_contents (val)); |
c906108c SS |
1776 | #endif |
1777 | } | |
1778 | \f | |
1779 | /* Unpack raw data (copied from debugee, target byte order) at VALADDR | |
1780 | as a long, or as a double, assuming the raw data is described | |
1781 | by type TYPE. Knows how to convert different sizes of values | |
1782 | and can convert between fixed and floating point. We don't assume | |
1783 | any alignment for the raw data. Return value is in host byte order. | |
1784 | ||
1785 | If you want functions and arrays to be coerced to pointers, and | |
1786 | references to be dereferenced, call value_as_long() instead. | |
1787 | ||
1788 | C++: It is assumed that the front-end has taken care of | |
1789 | all matters concerning pointers to members. A pointer | |
1790 | to member which reaches here is considered to be equivalent | |
1791 | to an INT (or some size). After all, it is only an offset. */ | |
1792 | ||
1793 | LONGEST | |
fc1a4b47 | 1794 | unpack_long (struct type *type, const gdb_byte *valaddr) |
c906108c | 1795 | { |
e17a4113 | 1796 | enum bfd_endian byte_order = gdbarch_byte_order (get_type_arch (type)); |
52f0bd74 AC |
1797 | enum type_code code = TYPE_CODE (type); |
1798 | int len = TYPE_LENGTH (type); | |
1799 | int nosign = TYPE_UNSIGNED (type); | |
c906108c | 1800 | |
c906108c SS |
1801 | switch (code) |
1802 | { | |
1803 | case TYPE_CODE_TYPEDEF: | |
1804 | return unpack_long (check_typedef (type), valaddr); | |
1805 | case TYPE_CODE_ENUM: | |
4f2aea11 | 1806 | case TYPE_CODE_FLAGS: |
c906108c SS |
1807 | case TYPE_CODE_BOOL: |
1808 | case TYPE_CODE_INT: | |
1809 | case TYPE_CODE_CHAR: | |
1810 | case TYPE_CODE_RANGE: | |
0d5de010 | 1811 | case TYPE_CODE_MEMBERPTR: |
c906108c | 1812 | if (nosign) |
e17a4113 | 1813 | return extract_unsigned_integer (valaddr, len, byte_order); |
c906108c | 1814 | else |
e17a4113 | 1815 | return extract_signed_integer (valaddr, len, byte_order); |
c906108c SS |
1816 | |
1817 | case TYPE_CODE_FLT: | |
96d2f608 | 1818 | return extract_typed_floating (valaddr, type); |
c906108c | 1819 | |
4ef30785 TJB |
1820 | case TYPE_CODE_DECFLOAT: |
1821 | /* libdecnumber has a function to convert from decimal to integer, but | |
1822 | it doesn't work when the decimal number has a fractional part. */ | |
e17a4113 | 1823 | return decimal_to_doublest (valaddr, len, byte_order); |
4ef30785 | 1824 | |
c906108c SS |
1825 | case TYPE_CODE_PTR: |
1826 | case TYPE_CODE_REF: | |
1827 | /* Assume a CORE_ADDR can fit in a LONGEST (for now). Not sure | |
c5aa993b | 1828 | whether we want this to be true eventually. */ |
4478b372 | 1829 | return extract_typed_address (valaddr, type); |
c906108c | 1830 | |
c906108c | 1831 | default: |
8a3fe4f8 | 1832 | error (_("Value can't be converted to integer.")); |
c906108c | 1833 | } |
c5aa993b | 1834 | return 0; /* Placate lint. */ |
c906108c SS |
1835 | } |
1836 | ||
1837 | /* Return a double value from the specified type and address. | |
1838 | INVP points to an int which is set to 0 for valid value, | |
1839 | 1 for invalid value (bad float format). In either case, | |
1840 | the returned double is OK to use. Argument is in target | |
1841 | format, result is in host format. */ | |
1842 | ||
1843 | DOUBLEST | |
fc1a4b47 | 1844 | unpack_double (struct type *type, const gdb_byte *valaddr, int *invp) |
c906108c | 1845 | { |
e17a4113 | 1846 | enum bfd_endian byte_order = gdbarch_byte_order (get_type_arch (type)); |
c906108c SS |
1847 | enum type_code code; |
1848 | int len; | |
1849 | int nosign; | |
1850 | ||
1851 | *invp = 0; /* Assume valid. */ | |
1852 | CHECK_TYPEDEF (type); | |
1853 | code = TYPE_CODE (type); | |
1854 | len = TYPE_LENGTH (type); | |
1855 | nosign = TYPE_UNSIGNED (type); | |
1856 | if (code == TYPE_CODE_FLT) | |
1857 | { | |
75bc7ddf AC |
1858 | /* NOTE: cagney/2002-02-19: There was a test here to see if the |
1859 | floating-point value was valid (using the macro | |
1860 | INVALID_FLOAT). That test/macro have been removed. | |
1861 | ||
1862 | It turns out that only the VAX defined this macro and then | |
1863 | only in a non-portable way. Fixing the portability problem | |
1864 | wouldn't help since the VAX floating-point code is also badly | |
1865 | bit-rotten. The target needs to add definitions for the | |
ea06eb3d | 1866 | methods gdbarch_float_format and gdbarch_double_format - these |
75bc7ddf AC |
1867 | exactly describe the target floating-point format. The |
1868 | problem here is that the corresponding floatformat_vax_f and | |
1869 | floatformat_vax_d values these methods should be set to are | |
1870 | also not defined either. Oops! | |
1871 | ||
1872 | Hopefully someone will add both the missing floatformat | |
ac79b88b DJ |
1873 | definitions and the new cases for floatformat_is_valid (). */ |
1874 | ||
1875 | if (!floatformat_is_valid (floatformat_from_type (type), valaddr)) | |
1876 | { | |
1877 | *invp = 1; | |
1878 | return 0.0; | |
1879 | } | |
1880 | ||
96d2f608 | 1881 | return extract_typed_floating (valaddr, type); |
c906108c | 1882 | } |
4ef30785 | 1883 | else if (code == TYPE_CODE_DECFLOAT) |
e17a4113 | 1884 | return decimal_to_doublest (valaddr, len, byte_order); |
c906108c SS |
1885 | else if (nosign) |
1886 | { | |
1887 | /* Unsigned -- be sure we compensate for signed LONGEST. */ | |
c906108c | 1888 | return (ULONGEST) unpack_long (type, valaddr); |
c906108c SS |
1889 | } |
1890 | else | |
1891 | { | |
1892 | /* Signed -- we are OK with unpack_long. */ | |
1893 | return unpack_long (type, valaddr); | |
1894 | } | |
1895 | } | |
1896 | ||
1897 | /* Unpack raw data (copied from debugee, target byte order) at VALADDR | |
1898 | as a CORE_ADDR, assuming the raw data is described by type TYPE. | |
1899 | We don't assume any alignment for the raw data. Return value is in | |
1900 | host byte order. | |
1901 | ||
1902 | If you want functions and arrays to be coerced to pointers, and | |
1aa20aa8 | 1903 | references to be dereferenced, call value_as_address() instead. |
c906108c SS |
1904 | |
1905 | C++: It is assumed that the front-end has taken care of | |
1906 | all matters concerning pointers to members. A pointer | |
1907 | to member which reaches here is considered to be equivalent | |
1908 | to an INT (or some size). After all, it is only an offset. */ | |
1909 | ||
1910 | CORE_ADDR | |
fc1a4b47 | 1911 | unpack_pointer (struct type *type, const gdb_byte *valaddr) |
c906108c SS |
1912 | { |
1913 | /* Assume a CORE_ADDR can fit in a LONGEST (for now). Not sure | |
1914 | whether we want this to be true eventually. */ | |
1915 | return unpack_long (type, valaddr); | |
1916 | } | |
4478b372 | 1917 | |
c906108c | 1918 | \f |
1596cb5d | 1919 | /* Get the value of the FIELDNO'th field (which must be static) of |
2c2738a0 DC |
1920 | TYPE. Return NULL if the field doesn't exist or has been |
1921 | optimized out. */ | |
c906108c | 1922 | |
f23631e4 | 1923 | struct value * |
fba45db2 | 1924 | value_static_field (struct type *type, int fieldno) |
c906108c | 1925 | { |
948e66d9 DJ |
1926 | struct value *retval; |
1927 | ||
1596cb5d | 1928 | switch (TYPE_FIELD_LOC_KIND (type, fieldno)) |
c906108c | 1929 | { |
1596cb5d | 1930 | case FIELD_LOC_KIND_PHYSADDR: |
52e9fde8 SS |
1931 | retval = value_at_lazy (TYPE_FIELD_TYPE (type, fieldno), |
1932 | TYPE_FIELD_STATIC_PHYSADDR (type, fieldno)); | |
1596cb5d DE |
1933 | break; |
1934 | case FIELD_LOC_KIND_PHYSNAME: | |
c906108c SS |
1935 | { |
1936 | char *phys_name = TYPE_FIELD_STATIC_PHYSNAME (type, fieldno); | |
a109c7c1 | 1937 | /*TYPE_FIELD_NAME (type, fieldno);*/ |
2570f2b7 | 1938 | struct symbol *sym = lookup_symbol (phys_name, 0, VAR_DOMAIN, 0); |
94af9270 | 1939 | |
948e66d9 | 1940 | if (sym == NULL) |
c906108c | 1941 | { |
a109c7c1 MS |
1942 | /* With some compilers, e.g. HP aCC, static data members are |
1943 | reported as non-debuggable symbols */ | |
1944 | struct minimal_symbol *msym = lookup_minimal_symbol (phys_name, | |
1945 | NULL, NULL); | |
1946 | ||
c906108c SS |
1947 | if (!msym) |
1948 | return NULL; | |
1949 | else | |
c5aa993b | 1950 | { |
52e9fde8 SS |
1951 | retval = value_at_lazy (TYPE_FIELD_TYPE (type, fieldno), |
1952 | SYMBOL_VALUE_ADDRESS (msym)); | |
c906108c SS |
1953 | } |
1954 | } | |
1955 | else | |
515ed532 | 1956 | retval = value_of_variable (sym, NULL); |
1596cb5d | 1957 | break; |
c906108c | 1958 | } |
1596cb5d | 1959 | default: |
f3574227 | 1960 | gdb_assert_not_reached ("unexpected field location kind"); |
1596cb5d DE |
1961 | } |
1962 | ||
948e66d9 | 1963 | return retval; |
c906108c SS |
1964 | } |
1965 | ||
4dfea560 DE |
1966 | /* Change the enclosing type of a value object VAL to NEW_ENCL_TYPE. |
1967 | You have to be careful here, since the size of the data area for the value | |
1968 | is set by the length of the enclosing type. So if NEW_ENCL_TYPE is bigger | |
1969 | than the old enclosing type, you have to allocate more space for the | |
1970 | data. */ | |
2b127877 | 1971 | |
4dfea560 DE |
1972 | void |
1973 | set_value_enclosing_type (struct value *val, struct type *new_encl_type) | |
2b127877 | 1974 | { |
3e3d7139 JG |
1975 | if (TYPE_LENGTH (new_encl_type) > TYPE_LENGTH (value_enclosing_type (val))) |
1976 | val->contents = | |
1977 | (gdb_byte *) xrealloc (val->contents, TYPE_LENGTH (new_encl_type)); | |
1978 | ||
1979 | val->enclosing_type = new_encl_type; | |
2b127877 DB |
1980 | } |
1981 | ||
c906108c SS |
1982 | /* Given a value ARG1 (offset by OFFSET bytes) |
1983 | of a struct or union type ARG_TYPE, | |
1984 | extract and return the value of one of its (non-static) fields. | |
1985 | FIELDNO says which field. */ | |
1986 | ||
f23631e4 AC |
1987 | struct value * |
1988 | value_primitive_field (struct value *arg1, int offset, | |
aa1ee363 | 1989 | int fieldno, struct type *arg_type) |
c906108c | 1990 | { |
f23631e4 | 1991 | struct value *v; |
52f0bd74 | 1992 | struct type *type; |
c906108c SS |
1993 | |
1994 | CHECK_TYPEDEF (arg_type); | |
1995 | type = TYPE_FIELD_TYPE (arg_type, fieldno); | |
c54eabfa JK |
1996 | |
1997 | /* Call check_typedef on our type to make sure that, if TYPE | |
1998 | is a TYPE_CODE_TYPEDEF, its length is set to the length | |
1999 | of the target type instead of zero. However, we do not | |
2000 | replace the typedef type by the target type, because we want | |
2001 | to keep the typedef in order to be able to print the type | |
2002 | description correctly. */ | |
2003 | check_typedef (type); | |
c906108c SS |
2004 | |
2005 | /* Handle packed fields */ | |
2006 | ||
2007 | if (TYPE_FIELD_BITSIZE (arg_type, fieldno)) | |
2008 | { | |
4ea48cc1 DJ |
2009 | /* Create a new value for the bitfield, with bitpos and bitsize |
2010 | set. If possible, arrange offset and bitpos so that we can | |
2011 | do a single aligned read of the size of the containing type. | |
2012 | Otherwise, adjust offset to the byte containing the first | |
2013 | bit. Assume that the address, offset, and embedded offset | |
2014 | are sufficiently aligned. */ | |
2015 | int bitpos = TYPE_FIELD_BITPOS (arg_type, fieldno); | |
2016 | int container_bitsize = TYPE_LENGTH (type) * 8; | |
2017 | ||
2018 | v = allocate_value_lazy (type); | |
df407dfe | 2019 | v->bitsize = TYPE_FIELD_BITSIZE (arg_type, fieldno); |
4ea48cc1 DJ |
2020 | if ((bitpos % container_bitsize) + v->bitsize <= container_bitsize |
2021 | && TYPE_LENGTH (type) <= (int) sizeof (LONGEST)) | |
2022 | v->bitpos = bitpos % container_bitsize; | |
2023 | else | |
2024 | v->bitpos = bitpos % 8; | |
38f12cfc TT |
2025 | v->offset = (value_embedded_offset (arg1) |
2026 | + offset | |
2027 | + (bitpos - v->bitpos) / 8); | |
4ea48cc1 DJ |
2028 | v->parent = arg1; |
2029 | value_incref (v->parent); | |
2030 | if (!value_lazy (arg1)) | |
2031 | value_fetch_lazy (v); | |
c906108c SS |
2032 | } |
2033 | else if (fieldno < TYPE_N_BASECLASSES (arg_type)) | |
2034 | { | |
2035 | /* This field is actually a base subobject, so preserve the | |
2036 | entire object's contents for later references to virtual | |
2037 | bases, etc. */ | |
a4e2ee12 DJ |
2038 | |
2039 | /* Lazy register values with offsets are not supported. */ | |
2040 | if (VALUE_LVAL (arg1) == lval_register && value_lazy (arg1)) | |
2041 | value_fetch_lazy (arg1); | |
2042 | ||
2043 | if (value_lazy (arg1)) | |
3e3d7139 | 2044 | v = allocate_value_lazy (value_enclosing_type (arg1)); |
c906108c | 2045 | else |
3e3d7139 JG |
2046 | { |
2047 | v = allocate_value (value_enclosing_type (arg1)); | |
2048 | memcpy (value_contents_all_raw (v), value_contents_all_raw (arg1), | |
2049 | TYPE_LENGTH (value_enclosing_type (arg1))); | |
2050 | } | |
2051 | v->type = type; | |
df407dfe | 2052 | v->offset = value_offset (arg1); |
13c3b5f5 AC |
2053 | v->embedded_offset = (offset + value_embedded_offset (arg1) |
2054 | + TYPE_FIELD_BITPOS (arg_type, fieldno) / 8); | |
c906108c SS |
2055 | } |
2056 | else | |
2057 | { | |
2058 | /* Plain old data member */ | |
2059 | offset += TYPE_FIELD_BITPOS (arg_type, fieldno) / 8; | |
a4e2ee12 DJ |
2060 | |
2061 | /* Lazy register values with offsets are not supported. */ | |
2062 | if (VALUE_LVAL (arg1) == lval_register && value_lazy (arg1)) | |
2063 | value_fetch_lazy (arg1); | |
2064 | ||
2065 | if (value_lazy (arg1)) | |
3e3d7139 | 2066 | v = allocate_value_lazy (type); |
c906108c | 2067 | else |
3e3d7139 JG |
2068 | { |
2069 | v = allocate_value (type); | |
2070 | memcpy (value_contents_raw (v), | |
2071 | value_contents_raw (arg1) + offset, | |
2072 | TYPE_LENGTH (type)); | |
2073 | } | |
df407dfe | 2074 | v->offset = (value_offset (arg1) + offset |
13c3b5f5 | 2075 | + value_embedded_offset (arg1)); |
c906108c | 2076 | } |
74bcbdf3 | 2077 | set_value_component_location (v, arg1); |
9ee8fc9d | 2078 | VALUE_REGNUM (v) = VALUE_REGNUM (arg1); |
0c16dd26 | 2079 | VALUE_FRAME_ID (v) = VALUE_FRAME_ID (arg1); |
c906108c SS |
2080 | return v; |
2081 | } | |
2082 | ||
2083 | /* Given a value ARG1 of a struct or union type, | |
2084 | extract and return the value of one of its (non-static) fields. | |
2085 | FIELDNO says which field. */ | |
2086 | ||
f23631e4 | 2087 | struct value * |
aa1ee363 | 2088 | value_field (struct value *arg1, int fieldno) |
c906108c | 2089 | { |
df407dfe | 2090 | return value_primitive_field (arg1, 0, fieldno, value_type (arg1)); |
c906108c SS |
2091 | } |
2092 | ||
2093 | /* Return a non-virtual function as a value. | |
2094 | F is the list of member functions which contains the desired method. | |
0478d61c FF |
2095 | J is an index into F which provides the desired method. |
2096 | ||
2097 | We only use the symbol for its address, so be happy with either a | |
2098 | full symbol or a minimal symbol. | |
2099 | */ | |
c906108c | 2100 | |
f23631e4 AC |
2101 | struct value * |
2102 | value_fn_field (struct value **arg1p, struct fn_field *f, int j, struct type *type, | |
fba45db2 | 2103 | int offset) |
c906108c | 2104 | { |
f23631e4 | 2105 | struct value *v; |
52f0bd74 | 2106 | struct type *ftype = TYPE_FN_FIELD_TYPE (f, j); |
0478d61c | 2107 | char *physname = TYPE_FN_FIELD_PHYSNAME (f, j); |
c906108c | 2108 | struct symbol *sym; |
0478d61c | 2109 | struct minimal_symbol *msym; |
c906108c | 2110 | |
2570f2b7 | 2111 | sym = lookup_symbol (physname, 0, VAR_DOMAIN, 0); |
5ae326fa | 2112 | if (sym != NULL) |
0478d61c | 2113 | { |
5ae326fa AC |
2114 | msym = NULL; |
2115 | } | |
2116 | else | |
2117 | { | |
2118 | gdb_assert (sym == NULL); | |
0478d61c | 2119 | msym = lookup_minimal_symbol (physname, NULL, NULL); |
5ae326fa AC |
2120 | if (msym == NULL) |
2121 | return NULL; | |
0478d61c FF |
2122 | } |
2123 | ||
c906108c | 2124 | v = allocate_value (ftype); |
0478d61c FF |
2125 | if (sym) |
2126 | { | |
42ae5230 | 2127 | set_value_address (v, BLOCK_START (SYMBOL_BLOCK_VALUE (sym))); |
0478d61c FF |
2128 | } |
2129 | else | |
2130 | { | |
bccdca4a UW |
2131 | /* The minimal symbol might point to a function descriptor; |
2132 | resolve it to the actual code address instead. */ | |
2133 | struct objfile *objfile = msymbol_objfile (msym); | |
2134 | struct gdbarch *gdbarch = get_objfile_arch (objfile); | |
2135 | ||
42ae5230 TT |
2136 | set_value_address (v, |
2137 | gdbarch_convert_from_func_ptr_addr | |
2138 | (gdbarch, SYMBOL_VALUE_ADDRESS (msym), ¤t_target)); | |
0478d61c | 2139 | } |
c906108c SS |
2140 | |
2141 | if (arg1p) | |
c5aa993b | 2142 | { |
df407dfe | 2143 | if (type != value_type (*arg1p)) |
c5aa993b JM |
2144 | *arg1p = value_ind (value_cast (lookup_pointer_type (type), |
2145 | value_addr (*arg1p))); | |
2146 | ||
070ad9f0 | 2147 | /* Move the `this' pointer according to the offset. |
c5aa993b JM |
2148 | VALUE_OFFSET (*arg1p) += offset; |
2149 | */ | |
c906108c SS |
2150 | } |
2151 | ||
2152 | return v; | |
2153 | } | |
2154 | ||
c906108c | 2155 | \f |
4ea48cc1 DJ |
2156 | /* Unpack a bitfield of the specified FIELD_TYPE, from the anonymous |
2157 | object at VALADDR. The bitfield starts at BITPOS bits and contains | |
2158 | BITSIZE bits. | |
c906108c SS |
2159 | |
2160 | Extracting bits depends on endianness of the machine. Compute the | |
2161 | number of least significant bits to discard. For big endian machines, | |
2162 | we compute the total number of bits in the anonymous object, subtract | |
2163 | off the bit count from the MSB of the object to the MSB of the | |
2164 | bitfield, then the size of the bitfield, which leaves the LSB discard | |
2165 | count. For little endian machines, the discard count is simply the | |
2166 | number of bits from the LSB of the anonymous object to the LSB of the | |
2167 | bitfield. | |
2168 | ||
2169 | If the field is signed, we also do sign extension. */ | |
2170 | ||
2171 | LONGEST | |
4ea48cc1 DJ |
2172 | unpack_bits_as_long (struct type *field_type, const gdb_byte *valaddr, |
2173 | int bitpos, int bitsize) | |
c906108c | 2174 | { |
4ea48cc1 | 2175 | enum bfd_endian byte_order = gdbarch_byte_order (get_type_arch (field_type)); |
c906108c SS |
2176 | ULONGEST val; |
2177 | ULONGEST valmask; | |
c906108c | 2178 | int lsbcount; |
4a76eae5 | 2179 | int bytes_read; |
c906108c | 2180 | |
4a76eae5 DJ |
2181 | /* Read the minimum number of bytes required; there may not be |
2182 | enough bytes to read an entire ULONGEST. */ | |
c906108c | 2183 | CHECK_TYPEDEF (field_type); |
4a76eae5 DJ |
2184 | if (bitsize) |
2185 | bytes_read = ((bitpos % 8) + bitsize + 7) / 8; | |
2186 | else | |
2187 | bytes_read = TYPE_LENGTH (field_type); | |
2188 | ||
2189 | val = extract_unsigned_integer (valaddr + bitpos / 8, | |
2190 | bytes_read, byte_order); | |
c906108c SS |
2191 | |
2192 | /* Extract bits. See comment above. */ | |
2193 | ||
4ea48cc1 | 2194 | if (gdbarch_bits_big_endian (get_type_arch (field_type))) |
4a76eae5 | 2195 | lsbcount = (bytes_read * 8 - bitpos % 8 - bitsize); |
c906108c SS |
2196 | else |
2197 | lsbcount = (bitpos % 8); | |
2198 | val >>= lsbcount; | |
2199 | ||
2200 | /* If the field does not entirely fill a LONGEST, then zero the sign bits. | |
2201 | If the field is signed, and is negative, then sign extend. */ | |
2202 | ||
2203 | if ((bitsize > 0) && (bitsize < 8 * (int) sizeof (val))) | |
2204 | { | |
2205 | valmask = (((ULONGEST) 1) << bitsize) - 1; | |
2206 | val &= valmask; | |
2207 | if (!TYPE_UNSIGNED (field_type)) | |
2208 | { | |
2209 | if (val & (valmask ^ (valmask >> 1))) | |
2210 | { | |
2211 | val |= ~valmask; | |
2212 | } | |
2213 | } | |
2214 | } | |
2215 | return (val); | |
2216 | } | |
2217 | ||
4ea48cc1 DJ |
2218 | /* Unpack a field FIELDNO of the specified TYPE, from the anonymous object at |
2219 | VALADDR. See unpack_bits_as_long for more details. */ | |
2220 | ||
2221 | LONGEST | |
2222 | unpack_field_as_long (struct type *type, const gdb_byte *valaddr, int fieldno) | |
2223 | { | |
2224 | int bitpos = TYPE_FIELD_BITPOS (type, fieldno); | |
2225 | int bitsize = TYPE_FIELD_BITSIZE (type, fieldno); | |
2226 | struct type *field_type = TYPE_FIELD_TYPE (type, fieldno); | |
2227 | ||
2228 | return unpack_bits_as_long (field_type, valaddr, bitpos, bitsize); | |
2229 | } | |
2230 | ||
c906108c SS |
2231 | /* Modify the value of a bitfield. ADDR points to a block of memory in |
2232 | target byte order; the bitfield starts in the byte pointed to. FIELDVAL | |
2233 | is the desired value of the field, in host byte order. BITPOS and BITSIZE | |
f4e88c8e | 2234 | indicate which bits (in target bit order) comprise the bitfield. |
19f220c3 | 2235 | Requires 0 < BITSIZE <= lbits, 0 <= BITPOS % 8 + BITSIZE <= lbits, and |
f4e88c8e | 2236 | 0 <= BITPOS, where lbits is the size of a LONGEST in bits. */ |
c906108c SS |
2237 | |
2238 | void | |
50810684 UW |
2239 | modify_field (struct type *type, gdb_byte *addr, |
2240 | LONGEST fieldval, int bitpos, int bitsize) | |
c906108c | 2241 | { |
e17a4113 | 2242 | enum bfd_endian byte_order = gdbarch_byte_order (get_type_arch (type)); |
f4e88c8e PH |
2243 | ULONGEST oword; |
2244 | ULONGEST mask = (ULONGEST) -1 >> (8 * sizeof (ULONGEST) - bitsize); | |
19f220c3 JK |
2245 | int bytesize; |
2246 | ||
2247 | /* Normalize BITPOS. */ | |
2248 | addr += bitpos / 8; | |
2249 | bitpos %= 8; | |
c906108c SS |
2250 | |
2251 | /* If a negative fieldval fits in the field in question, chop | |
2252 | off the sign extension bits. */ | |
f4e88c8e PH |
2253 | if ((~fieldval & ~(mask >> 1)) == 0) |
2254 | fieldval &= mask; | |
c906108c SS |
2255 | |
2256 | /* Warn if value is too big to fit in the field in question. */ | |
f4e88c8e | 2257 | if (0 != (fieldval & ~mask)) |
c906108c SS |
2258 | { |
2259 | /* FIXME: would like to include fieldval in the message, but | |
c5aa993b | 2260 | we don't have a sprintf_longest. */ |
8a3fe4f8 | 2261 | warning (_("Value does not fit in %d bits."), bitsize); |
c906108c SS |
2262 | |
2263 | /* Truncate it, otherwise adjoining fields may be corrupted. */ | |
f4e88c8e | 2264 | fieldval &= mask; |
c906108c SS |
2265 | } |
2266 | ||
19f220c3 JK |
2267 | /* Ensure no bytes outside of the modified ones get accessed as it may cause |
2268 | false valgrind reports. */ | |
2269 | ||
2270 | bytesize = (bitpos + bitsize + 7) / 8; | |
2271 | oword = extract_unsigned_integer (addr, bytesize, byte_order); | |
c906108c SS |
2272 | |
2273 | /* Shifting for bit field depends on endianness of the target machine. */ | |
50810684 | 2274 | if (gdbarch_bits_big_endian (get_type_arch (type))) |
19f220c3 | 2275 | bitpos = bytesize * 8 - bitpos - bitsize; |
c906108c | 2276 | |
f4e88c8e | 2277 | oword &= ~(mask << bitpos); |
c906108c SS |
2278 | oword |= fieldval << bitpos; |
2279 | ||
19f220c3 | 2280 | store_unsigned_integer (addr, bytesize, byte_order, oword); |
c906108c SS |
2281 | } |
2282 | \f | |
14d06750 | 2283 | /* Pack NUM into BUF using a target format of TYPE. */ |
c906108c | 2284 | |
14d06750 DJ |
2285 | void |
2286 | pack_long (gdb_byte *buf, struct type *type, LONGEST num) | |
c906108c | 2287 | { |
e17a4113 | 2288 | enum bfd_endian byte_order = gdbarch_byte_order (get_type_arch (type)); |
52f0bd74 | 2289 | int len; |
14d06750 DJ |
2290 | |
2291 | type = check_typedef (type); | |
c906108c SS |
2292 | len = TYPE_LENGTH (type); |
2293 | ||
14d06750 | 2294 | switch (TYPE_CODE (type)) |
c906108c | 2295 | { |
c906108c SS |
2296 | case TYPE_CODE_INT: |
2297 | case TYPE_CODE_CHAR: | |
2298 | case TYPE_CODE_ENUM: | |
4f2aea11 | 2299 | case TYPE_CODE_FLAGS: |
c906108c SS |
2300 | case TYPE_CODE_BOOL: |
2301 | case TYPE_CODE_RANGE: | |
0d5de010 | 2302 | case TYPE_CODE_MEMBERPTR: |
e17a4113 | 2303 | store_signed_integer (buf, len, byte_order, num); |
c906108c | 2304 | break; |
c5aa993b | 2305 | |
c906108c SS |
2306 | case TYPE_CODE_REF: |
2307 | case TYPE_CODE_PTR: | |
14d06750 | 2308 | store_typed_address (buf, type, (CORE_ADDR) num); |
c906108c | 2309 | break; |
c5aa993b | 2310 | |
c906108c | 2311 | default: |
14d06750 DJ |
2312 | error (_("Unexpected type (%d) encountered for integer constant."), |
2313 | TYPE_CODE (type)); | |
c906108c | 2314 | } |
14d06750 DJ |
2315 | } |
2316 | ||
2317 | ||
595939de PM |
2318 | /* Pack NUM into BUF using a target format of TYPE. */ |
2319 | ||
2320 | void | |
2321 | pack_unsigned_long (gdb_byte *buf, struct type *type, ULONGEST num) | |
2322 | { | |
2323 | int len; | |
2324 | enum bfd_endian byte_order; | |
2325 | ||
2326 | type = check_typedef (type); | |
2327 | len = TYPE_LENGTH (type); | |
2328 | byte_order = gdbarch_byte_order (get_type_arch (type)); | |
2329 | ||
2330 | switch (TYPE_CODE (type)) | |
2331 | { | |
2332 | case TYPE_CODE_INT: | |
2333 | case TYPE_CODE_CHAR: | |
2334 | case TYPE_CODE_ENUM: | |
2335 | case TYPE_CODE_FLAGS: | |
2336 | case TYPE_CODE_BOOL: | |
2337 | case TYPE_CODE_RANGE: | |
2338 | case TYPE_CODE_MEMBERPTR: | |
2339 | store_unsigned_integer (buf, len, byte_order, num); | |
2340 | break; | |
2341 | ||
2342 | case TYPE_CODE_REF: | |
2343 | case TYPE_CODE_PTR: | |
2344 | store_typed_address (buf, type, (CORE_ADDR) num); | |
2345 | break; | |
2346 | ||
2347 | default: | |
2348 | error (_("\ | |
2349 | Unexpected type (%d) encountered for unsigned integer constant."), | |
2350 | TYPE_CODE (type)); | |
2351 | } | |
2352 | } | |
2353 | ||
2354 | ||
14d06750 DJ |
2355 | /* Convert C numbers into newly allocated values. */ |
2356 | ||
2357 | struct value * | |
2358 | value_from_longest (struct type *type, LONGEST num) | |
2359 | { | |
2360 | struct value *val = allocate_value (type); | |
2361 | ||
2362 | pack_long (value_contents_raw (val), type, num); | |
c906108c SS |
2363 | return val; |
2364 | } | |
2365 | ||
4478b372 | 2366 | |
595939de PM |
2367 | /* Convert C unsigned numbers into newly allocated values. */ |
2368 | ||
2369 | struct value * | |
2370 | value_from_ulongest (struct type *type, ULONGEST num) | |
2371 | { | |
2372 | struct value *val = allocate_value (type); | |
2373 | ||
2374 | pack_unsigned_long (value_contents_raw (val), type, num); | |
2375 | ||
2376 | return val; | |
2377 | } | |
2378 | ||
2379 | ||
4478b372 JB |
2380 | /* Create a value representing a pointer of type TYPE to the address |
2381 | ADDR. */ | |
f23631e4 | 2382 | struct value * |
4478b372 JB |
2383 | value_from_pointer (struct type *type, CORE_ADDR addr) |
2384 | { | |
f23631e4 | 2385 | struct value *val = allocate_value (type); |
a109c7c1 | 2386 | |
cab0c772 | 2387 | store_typed_address (value_contents_raw (val), check_typedef (type), addr); |
4478b372 JB |
2388 | return val; |
2389 | } | |
2390 | ||
2391 | ||
8acb6b92 TT |
2392 | /* Create a value of type TYPE whose contents come from VALADDR, if it |
2393 | is non-null, and whose memory address (in the inferior) is | |
2394 | ADDRESS. */ | |
2395 | ||
2396 | struct value * | |
2397 | value_from_contents_and_address (struct type *type, | |
2398 | const gdb_byte *valaddr, | |
2399 | CORE_ADDR address) | |
2400 | { | |
2401 | struct value *v = allocate_value (type); | |
a109c7c1 | 2402 | |
8acb6b92 TT |
2403 | if (valaddr == NULL) |
2404 | set_value_lazy (v, 1); | |
2405 | else | |
2406 | memcpy (value_contents_raw (v), valaddr, TYPE_LENGTH (type)); | |
42ae5230 | 2407 | set_value_address (v, address); |
33d502b4 | 2408 | VALUE_LVAL (v) = lval_memory; |
8acb6b92 TT |
2409 | return v; |
2410 | } | |
2411 | ||
f23631e4 | 2412 | struct value * |
fba45db2 | 2413 | value_from_double (struct type *type, DOUBLEST num) |
c906108c | 2414 | { |
f23631e4 | 2415 | struct value *val = allocate_value (type); |
c906108c | 2416 | struct type *base_type = check_typedef (type); |
52f0bd74 | 2417 | enum type_code code = TYPE_CODE (base_type); |
c906108c SS |
2418 | |
2419 | if (code == TYPE_CODE_FLT) | |
2420 | { | |
990a07ab | 2421 | store_typed_floating (value_contents_raw (val), base_type, num); |
c906108c SS |
2422 | } |
2423 | else | |
8a3fe4f8 | 2424 | error (_("Unexpected type encountered for floating constant.")); |
c906108c SS |
2425 | |
2426 | return val; | |
2427 | } | |
994b9211 | 2428 | |
27bc4d80 | 2429 | struct value * |
4ef30785 | 2430 | value_from_decfloat (struct type *type, const gdb_byte *dec) |
27bc4d80 TJB |
2431 | { |
2432 | struct value *val = allocate_value (type); | |
27bc4d80 | 2433 | |
4ef30785 | 2434 | memcpy (value_contents_raw (val), dec, TYPE_LENGTH (type)); |
27bc4d80 TJB |
2435 | return val; |
2436 | } | |
2437 | ||
994b9211 AC |
2438 | struct value * |
2439 | coerce_ref (struct value *arg) | |
2440 | { | |
df407dfe | 2441 | struct type *value_type_arg_tmp = check_typedef (value_type (arg)); |
a109c7c1 | 2442 | |
994b9211 AC |
2443 | if (TYPE_CODE (value_type_arg_tmp) == TYPE_CODE_REF) |
2444 | arg = value_at_lazy (TYPE_TARGET_TYPE (value_type_arg_tmp), | |
df407dfe | 2445 | unpack_pointer (value_type (arg), |
0fd88904 | 2446 | value_contents (arg))); |
994b9211 AC |
2447 | return arg; |
2448 | } | |
2449 | ||
2450 | struct value * | |
2451 | coerce_array (struct value *arg) | |
2452 | { | |
f3134b88 TT |
2453 | struct type *type; |
2454 | ||
994b9211 | 2455 | arg = coerce_ref (arg); |
f3134b88 TT |
2456 | type = check_typedef (value_type (arg)); |
2457 | ||
2458 | switch (TYPE_CODE (type)) | |
2459 | { | |
2460 | case TYPE_CODE_ARRAY: | |
7346b668 | 2461 | if (!TYPE_VECTOR (type) && current_language->c_style_arrays) |
f3134b88 TT |
2462 | arg = value_coerce_array (arg); |
2463 | break; | |
2464 | case TYPE_CODE_FUNC: | |
2465 | arg = value_coerce_function (arg); | |
2466 | break; | |
2467 | } | |
994b9211 AC |
2468 | return arg; |
2469 | } | |
c906108c | 2470 | \f |
c906108c | 2471 | |
48436ce6 AC |
2472 | /* Return true if the function returning the specified type is using |
2473 | the convention of returning structures in memory (passing in the | |
82585c72 | 2474 | address as a hidden first parameter). */ |
c906108c SS |
2475 | |
2476 | int | |
d80b854b UW |
2477 | using_struct_return (struct gdbarch *gdbarch, |
2478 | struct type *func_type, struct type *value_type) | |
c906108c | 2479 | { |
52f0bd74 | 2480 | enum type_code code = TYPE_CODE (value_type); |
c906108c SS |
2481 | |
2482 | if (code == TYPE_CODE_ERROR) | |
8a3fe4f8 | 2483 | error (_("Function return type unknown.")); |
c906108c | 2484 | |
667e784f AC |
2485 | if (code == TYPE_CODE_VOID) |
2486 | /* A void return value is never in memory. See also corresponding | |
44e5158b | 2487 | code in "print_return_value". */ |
667e784f AC |
2488 | return 0; |
2489 | ||
92ad9cd9 | 2490 | /* Probe the architecture for the return-value convention. */ |
d80b854b | 2491 | return (gdbarch_return_value (gdbarch, func_type, value_type, |
92ad9cd9 | 2492 | NULL, NULL, NULL) |
31db7b6c | 2493 | != RETURN_VALUE_REGISTER_CONVENTION); |
c906108c SS |
2494 | } |
2495 | ||
42be36b3 CT |
2496 | /* Set the initialized field in a value struct. */ |
2497 | ||
2498 | void | |
2499 | set_value_initialized (struct value *val, int status) | |
2500 | { | |
2501 | val->initialized = status; | |
2502 | } | |
2503 | ||
2504 | /* Return the initialized field in a value struct. */ | |
2505 | ||
2506 | int | |
2507 | value_initialized (struct value *val) | |
2508 | { | |
2509 | return val->initialized; | |
2510 | } | |
2511 | ||
c906108c | 2512 | void |
fba45db2 | 2513 | _initialize_values (void) |
c906108c | 2514 | { |
1a966eab AC |
2515 | add_cmd ("convenience", no_class, show_convenience, _("\ |
2516 | Debugger convenience (\"$foo\") variables.\n\ | |
c906108c | 2517 | These variables are created when you assign them values;\n\ |
1a966eab AC |
2518 | thus, \"print $foo=1\" gives \"$foo\" the value 1. Values may be any type.\n\ |
2519 | \n\ | |
c906108c SS |
2520 | A few convenience variables are given values automatically:\n\ |
2521 | \"$_\"holds the last address examined with \"x\" or \"info lines\",\n\ | |
1a966eab | 2522 | \"$__\" holds the contents of the last address examined with \"x\"."), |
c906108c SS |
2523 | &showlist); |
2524 | ||
2525 | add_cmd ("values", no_class, show_values, | |
1a966eab | 2526 | _("Elements of value history around item number IDX (or last ten)."), |
c906108c | 2527 | &showlist); |
53e5f3cf AS |
2528 | |
2529 | add_com ("init-if-undefined", class_vars, init_if_undefined_command, _("\ | |
2530 | Initialize a convenience variable if necessary.\n\ | |
2531 | init-if-undefined VARIABLE = EXPRESSION\n\ | |
2532 | Set an internal VARIABLE to the result of the EXPRESSION if it does not\n\ | |
2533 | exist or does not contain a value. The EXPRESSION is not evaluated if the\n\ | |
2534 | VARIABLE is already initialized.")); | |
bc3b79fd TJB |
2535 | |
2536 | add_prefix_cmd ("function", no_class, function_command, _("\ | |
2537 | Placeholder command for showing help on convenience functions."), | |
2538 | &functionlist, "function ", 0, &cmdlist); | |
c906108c | 2539 | } |