Commit | Line | Data |
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c906108c | 1 | /* Find a variable's value in memory, for GDB, the GNU debugger. |
1bac305b | 2 | |
3666a048 | 3 | Copyright (C) 1986-2021 Free Software Foundation, Inc. |
c906108c | 4 | |
c5aa993b | 5 | This file is part of GDB. |
c906108c | 6 | |
c5aa993b JM |
7 | This program is free software; you can redistribute it and/or modify |
8 | it under the terms of the GNU General Public License as published by | |
a9762ec7 | 9 | the Free Software Foundation; either version 3 of the License, or |
c5aa993b | 10 | (at your option) any later version. |
c906108c | 11 | |
c5aa993b JM |
12 | This program is distributed in the hope that it will be useful, |
13 | but WITHOUT ANY WARRANTY; without even the implied warranty of | |
14 | MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the | |
15 | GNU General Public License for more details. | |
c906108c | 16 | |
c5aa993b | 17 | You should have received a copy of the GNU General Public License |
a9762ec7 | 18 | along with this program. If not, see <http://www.gnu.org/licenses/>. */ |
c906108c SS |
19 | |
20 | #include "defs.h" | |
4de283e4 TT |
21 | #include "symtab.h" |
22 | #include "gdbtypes.h" | |
c906108c | 23 | #include "frame.h" |
4de283e4 | 24 | #include "value.h" |
c906108c SS |
25 | #include "gdbcore.h" |
26 | #include "inferior.h" | |
d55e5aa6 | 27 | #include "target.h" |
4de283e4 TT |
28 | #include "symfile.h" /* for overlay functions */ |
29 | #include "regcache.h" | |
eb8bc282 | 30 | #include "user-regs.h" |
4de283e4 TT |
31 | #include "block.h" |
32 | #include "objfiles.h" | |
33 | #include "language.h" | |
82ca8957 | 34 | #include "dwarf2/loc.h" |
268a13a5 | 35 | #include "gdbsupport/selftest.h" |
c906108c | 36 | |
9659616a MS |
37 | /* Basic byte-swapping routines. All 'extract' functions return a |
38 | host-format integer from a target-format integer at ADDR which is | |
39 | LEN bytes long. */ | |
c906108c SS |
40 | |
41 | #if TARGET_CHAR_BIT != 8 || HOST_CHAR_BIT != 8 | |
42 | /* 8 bit characters are a pretty safe assumption these days, so we | |
43 | assume it throughout all these swapping routines. If we had to deal with | |
44 | 9 bit characters, we would need to make len be in bits and would have | |
45 | to re-write these routines... */ | |
c5aa993b | 46 | you lose |
c906108c SS |
47 | #endif |
48 | ||
6f98355c YQ |
49 | template<typename T, typename> |
50 | T | |
51 | extract_integer (const gdb_byte *addr, int len, enum bfd_endian byte_order) | |
c906108c | 52 | { |
0101665f | 53 | typename std::make_unsigned<T>::type retval = 0; |
37611a2b AC |
54 | const unsigned char *p; |
55 | const unsigned char *startaddr = addr; | |
56 | const unsigned char *endaddr = startaddr + len; | |
c906108c | 57 | |
6f98355c | 58 | if (len > (int) sizeof (T)) |
8a3fe4f8 AC |
59 | error (_("\ |
60 | That operation is not available on integers of more than %d bytes."), | |
6f98355c | 61 | (int) sizeof (T)); |
c906108c SS |
62 | |
63 | /* Start at the most significant end of the integer, and work towards | |
64 | the least significant. */ | |
e17a4113 | 65 | if (byte_order == BFD_ENDIAN_BIG) |
c906108c SS |
66 | { |
67 | p = startaddr; | |
6f98355c YQ |
68 | if (std::is_signed<T>::value) |
69 | { | |
70 | /* Do the sign extension once at the start. */ | |
71 | retval = ((LONGEST) * p ^ 0x80) - 0x80; | |
72 | ++p; | |
73 | } | |
74 | for (; p < endaddr; ++p) | |
c906108c SS |
75 | retval = (retval << 8) | *p; |
76 | } | |
77 | else | |
78 | { | |
79 | p = endaddr - 1; | |
6f98355c YQ |
80 | if (std::is_signed<T>::value) |
81 | { | |
82 | /* Do the sign extension once at the start. */ | |
83 | retval = ((LONGEST) * p ^ 0x80) - 0x80; | |
84 | --p; | |
85 | } | |
86 | for (; p >= startaddr; --p) | |
c906108c SS |
87 | retval = (retval << 8) | *p; |
88 | } | |
89 | return retval; | |
90 | } | |
91 | ||
6f98355c YQ |
92 | /* Explicit instantiations. */ |
93 | template LONGEST extract_integer<LONGEST> (const gdb_byte *addr, int len, | |
94 | enum bfd_endian byte_order); | |
95 | template ULONGEST extract_integer<ULONGEST> (const gdb_byte *addr, int len, | |
96 | enum bfd_endian byte_order); | |
c906108c SS |
97 | |
98 | /* Sometimes a long long unsigned integer can be extracted as a | |
99 | LONGEST value. This is done so that we can print these values | |
100 | better. If this integer can be converted to a LONGEST, this | |
101 | function returns 1 and sets *PVAL. Otherwise it returns 0. */ | |
102 | ||
103 | int | |
0d509538 | 104 | extract_long_unsigned_integer (const gdb_byte *addr, int orig_len, |
e17a4113 | 105 | enum bfd_endian byte_order, LONGEST *pval) |
c906108c | 106 | { |
0d509538 AC |
107 | const gdb_byte *p; |
108 | const gdb_byte *first_addr; | |
c906108c SS |
109 | int len; |
110 | ||
111 | len = orig_len; | |
e17a4113 | 112 | if (byte_order == BFD_ENDIAN_BIG) |
c906108c | 113 | { |
0d509538 AC |
114 | for (p = addr; |
115 | len > (int) sizeof (LONGEST) && p < addr + orig_len; | |
c906108c SS |
116 | p++) |
117 | { | |
118 | if (*p == 0) | |
119 | len--; | |
120 | else | |
121 | break; | |
122 | } | |
123 | first_addr = p; | |
124 | } | |
125 | else | |
126 | { | |
0d509538 AC |
127 | first_addr = addr; |
128 | for (p = addr + orig_len - 1; | |
129 | len > (int) sizeof (LONGEST) && p >= addr; | |
c906108c SS |
130 | p--) |
131 | { | |
132 | if (*p == 0) | |
133 | len--; | |
134 | else | |
135 | break; | |
136 | } | |
137 | } | |
138 | ||
139 | if (len <= (int) sizeof (LONGEST)) | |
140 | { | |
141 | *pval = (LONGEST) extract_unsigned_integer (first_addr, | |
e17a4113 UW |
142 | sizeof (LONGEST), |
143 | byte_order); | |
c906108c SS |
144 | return 1; |
145 | } | |
146 | ||
147 | return 0; | |
148 | } | |
149 | ||
4478b372 | 150 | |
4478b372 JB |
151 | /* Treat the bytes at BUF as a pointer of type TYPE, and return the |
152 | address it represents. */ | |
153 | CORE_ADDR | |
0d509538 | 154 | extract_typed_address (const gdb_byte *buf, struct type *type) |
4478b372 | 155 | { |
78134374 | 156 | if (type->code () != TYPE_CODE_PTR && !TYPE_IS_REFERENCE (type)) |
8e65ff28 | 157 | internal_error (__FILE__, __LINE__, |
e2e0b3e5 AC |
158 | _("extract_typed_address: " |
159 | "type is not a pointer or reference")); | |
4478b372 | 160 | |
8ee511af | 161 | return gdbarch_pointer_to_address (type->arch (), type, buf); |
4478b372 JB |
162 | } |
163 | ||
9659616a MS |
164 | /* All 'store' functions accept a host-format integer and store a |
165 | target-format integer at ADDR which is LEN bytes long. */ | |
6f98355c | 166 | template<typename T, typename> |
c906108c | 167 | void |
6f98355c YQ |
168 | store_integer (gdb_byte *addr, int len, enum bfd_endian byte_order, |
169 | T val) | |
c906108c | 170 | { |
0d509538 AC |
171 | gdb_byte *p; |
172 | gdb_byte *startaddr = addr; | |
173 | gdb_byte *endaddr = startaddr + len; | |
c906108c SS |
174 | |
175 | /* Start at the least significant end of the integer, and work towards | |
176 | the most significant. */ | |
e17a4113 | 177 | if (byte_order == BFD_ENDIAN_BIG) |
c906108c SS |
178 | { |
179 | for (p = endaddr - 1; p >= startaddr; --p) | |
180 | { | |
181 | *p = val & 0xff; | |
182 | val >>= 8; | |
183 | } | |
184 | } | |
185 | else | |
186 | { | |
187 | for (p = startaddr; p < endaddr; ++p) | |
188 | { | |
189 | *p = val & 0xff; | |
190 | val >>= 8; | |
191 | } | |
192 | } | |
193 | } | |
194 | ||
6f98355c YQ |
195 | /* Explicit instantiations. */ |
196 | template void store_integer (gdb_byte *addr, int len, | |
197 | enum bfd_endian byte_order, | |
198 | LONGEST val); | |
c906108c | 199 | |
6f98355c YQ |
200 | template void store_integer (gdb_byte *addr, int len, |
201 | enum bfd_endian byte_order, | |
202 | ULONGEST val); | |
c906108c | 203 | |
4478b372 JB |
204 | /* Store the address ADDR as a pointer of type TYPE at BUF, in target |
205 | form. */ | |
206 | void | |
0d509538 | 207 | store_typed_address (gdb_byte *buf, struct type *type, CORE_ADDR addr) |
4478b372 | 208 | { |
78134374 | 209 | if (type->code () != TYPE_CODE_PTR && !TYPE_IS_REFERENCE (type)) |
8e65ff28 | 210 | internal_error (__FILE__, __LINE__, |
e2e0b3e5 AC |
211 | _("store_typed_address: " |
212 | "type is not a pointer or reference")); | |
4478b372 | 213 | |
8ee511af | 214 | gdbarch_address_to_pointer (type->arch (), type, buf, addr); |
4478b372 JB |
215 | } |
216 | ||
b057297a AH |
217 | /* Copy a value from SOURCE of size SOURCE_SIZE bytes to DEST of size DEST_SIZE |
218 | bytes. If SOURCE_SIZE is greater than DEST_SIZE, then truncate the most | |
219 | significant bytes. If SOURCE_SIZE is less than DEST_SIZE then either sign | |
220 | or zero extended according to IS_SIGNED. Values are stored in memory with | |
405feb71 | 221 | endianness BYTE_ORDER. */ |
4478b372 | 222 | |
b057297a AH |
223 | void |
224 | copy_integer_to_size (gdb_byte *dest, int dest_size, const gdb_byte *source, | |
225 | int source_size, bool is_signed, | |
226 | enum bfd_endian byte_order) | |
227 | { | |
228 | signed int size_diff = dest_size - source_size; | |
229 | ||
230 | /* Copy across everything from SOURCE that can fit into DEST. */ | |
231 | ||
232 | if (byte_order == BFD_ENDIAN_BIG && size_diff > 0) | |
233 | memcpy (dest + size_diff, source, source_size); | |
234 | else if (byte_order == BFD_ENDIAN_BIG && size_diff < 0) | |
235 | memcpy (dest, source - size_diff, dest_size); | |
236 | else | |
237 | memcpy (dest, source, std::min (source_size, dest_size)); | |
238 | ||
239 | /* Fill the remaining space in DEST by either zero extending or sign | |
240 | extending. */ | |
241 | ||
242 | if (size_diff > 0) | |
243 | { | |
244 | gdb_byte extension = 0; | |
245 | if (is_signed | |
246 | && ((byte_order != BFD_ENDIAN_BIG && source[source_size - 1] & 0x80) | |
247 | || (byte_order == BFD_ENDIAN_BIG && source[0] & 0x80))) | |
248 | extension = 0xff; | |
249 | ||
250 | /* Extend into MSBs of SOURCE. */ | |
251 | if (byte_order == BFD_ENDIAN_BIG) | |
252 | memset (dest, extension, size_diff); | |
253 | else | |
254 | memset (dest + source_size, extension, size_diff); | |
255 | } | |
256 | } | |
4478b372 | 257 | |
376c9600 AC |
258 | /* Return a `value' with the contents of (virtual or cooked) register |
259 | REGNUM as found in the specified FRAME. The register's type is | |
78134374 | 260 | determined by register_type (). */ |
c906108c | 261 | |
3d6d86c6 | 262 | struct value * |
376c9600 | 263 | value_of_register (int regnum, struct frame_info *frame) |
c906108c | 264 | { |
e9e45075 | 265 | struct gdbarch *gdbarch = get_frame_arch (frame); |
3d6d86c6 | 266 | struct value *reg_val; |
c906108c | 267 | |
9564ee9f | 268 | /* User registers lie completely outside of the range of normal |
0406ec40 | 269 | registers. Catch them early so that the target never sees them. */ |
f6efe3f8 | 270 | if (regnum >= gdbarch_num_cooked_regs (gdbarch)) |
eb8bc282 | 271 | return value_of_user_reg (regnum, frame); |
0406ec40 | 272 | |
d5b495b4 PA |
273 | reg_val = value_of_register_lazy (frame, regnum); |
274 | value_fetch_lazy (reg_val); | |
c906108c SS |
275 | return reg_val; |
276 | } | |
4478b372 | 277 | |
9214ee5f DJ |
278 | /* Return a `value' with the contents of (virtual or cooked) register |
279 | REGNUM as found in the specified FRAME. The register's type is | |
78134374 | 280 | determined by register_type (). The value is not fetched. */ |
9214ee5f DJ |
281 | |
282 | struct value * | |
283 | value_of_register_lazy (struct frame_info *frame, int regnum) | |
284 | { | |
285 | struct gdbarch *gdbarch = get_frame_arch (frame); | |
286 | struct value *reg_val; | |
41b56feb | 287 | struct frame_info *next_frame; |
9214ee5f | 288 | |
f6efe3f8 | 289 | gdb_assert (regnum < gdbarch_num_cooked_regs (gdbarch)); |
9214ee5f | 290 | |
41b56feb KB |
291 | gdb_assert (frame != NULL); |
292 | ||
293 | next_frame = get_next_frame_sentinel_okay (frame); | |
9fc501fd AB |
294 | |
295 | /* In some cases NEXT_FRAME may not have a valid frame-id yet. This can | |
296 | happen if we end up trying to unwind a register as part of the frame | |
297 | sniffer. The only time that we get here without a valid frame-id is | |
298 | if NEXT_FRAME is an inline frame. If this is the case then we can | |
299 | avoid getting into trouble here by skipping past the inline frames. */ | |
300 | while (get_frame_type (next_frame) == INLINE_FRAME) | |
301 | next_frame = get_next_frame_sentinel_okay (next_frame); | |
41b56feb KB |
302 | |
303 | /* We should have a valid next frame. */ | |
304 | gdb_assert (frame_id_p (get_frame_id (next_frame))); | |
9214ee5f | 305 | |
41e8491f | 306 | reg_val = allocate_value_lazy (register_type (gdbarch, regnum)); |
9214ee5f DJ |
307 | VALUE_LVAL (reg_val) = lval_register; |
308 | VALUE_REGNUM (reg_val) = regnum; | |
41b56feb KB |
309 | VALUE_NEXT_FRAME_ID (reg_val) = get_frame_id (next_frame); |
310 | ||
9214ee5f DJ |
311 | return reg_val; |
312 | } | |
313 | ||
4478b372 JB |
314 | /* Given a pointer of type TYPE in target form in BUF, return the |
315 | address it represents. */ | |
316 | CORE_ADDR | |
9898f801 UW |
317 | unsigned_pointer_to_address (struct gdbarch *gdbarch, |
318 | struct type *type, const gdb_byte *buf) | |
4478b372 | 319 | { |
34877895 | 320 | enum bfd_endian byte_order = type_byte_order (type); |
bb9bcb69 | 321 | |
e17a4113 | 322 | return extract_unsigned_integer (buf, TYPE_LENGTH (type), byte_order); |
4478b372 JB |
323 | } |
324 | ||
ac2e2ef7 | 325 | CORE_ADDR |
9898f801 UW |
326 | signed_pointer_to_address (struct gdbarch *gdbarch, |
327 | struct type *type, const gdb_byte *buf) | |
ac2e2ef7 | 328 | { |
34877895 | 329 | enum bfd_endian byte_order = type_byte_order (type); |
bb9bcb69 | 330 | |
e17a4113 | 331 | return extract_signed_integer (buf, TYPE_LENGTH (type), byte_order); |
ac2e2ef7 | 332 | } |
4478b372 JB |
333 | |
334 | /* Given an address, store it as a pointer of type TYPE in target | |
335 | format in BUF. */ | |
336 | void | |
9898f801 UW |
337 | unsigned_address_to_pointer (struct gdbarch *gdbarch, struct type *type, |
338 | gdb_byte *buf, CORE_ADDR addr) | |
4478b372 | 339 | { |
34877895 | 340 | enum bfd_endian byte_order = type_byte_order (type); |
bb9bcb69 | 341 | |
e17a4113 | 342 | store_unsigned_integer (buf, TYPE_LENGTH (type), byte_order, addr); |
4478b372 JB |
343 | } |
344 | ||
ac2e2ef7 | 345 | void |
9898f801 UW |
346 | address_to_signed_pointer (struct gdbarch *gdbarch, struct type *type, |
347 | gdb_byte *buf, CORE_ADDR addr) | |
ac2e2ef7 | 348 | { |
34877895 | 349 | enum bfd_endian byte_order = type_byte_order (type); |
bb9bcb69 | 350 | |
e17a4113 | 351 | store_signed_integer (buf, TYPE_LENGTH (type), byte_order, addr); |
ac2e2ef7 | 352 | } |
c906108c | 353 | \f |
0b31a4bc TT |
354 | /* See value.h. */ |
355 | ||
356 | enum symbol_needs_kind | |
357 | symbol_read_needs (struct symbol *sym) | |
c906108c | 358 | { |
24d6c2a0 | 359 | if (SYMBOL_COMPUTED_OPS (sym) != NULL) |
0b31a4bc | 360 | return SYMBOL_COMPUTED_OPS (sym)->get_symbol_read_needs (sym); |
24d6c2a0 | 361 | |
c906108c SS |
362 | switch (SYMBOL_CLASS (sym)) |
363 | { | |
364 | /* All cases listed explicitly so that gcc -Wall will detect it if | |
dda83cd7 | 365 | we failed to consider one. */ |
4c2df51b | 366 | case LOC_COMPUTED: |
24d6c2a0 | 367 | gdb_assert_not_reached (_("LOC_COMPUTED variable missing a method")); |
4c2df51b | 368 | |
c906108c SS |
369 | case LOC_REGISTER: |
370 | case LOC_ARG: | |
371 | case LOC_REF_ARG: | |
c906108c SS |
372 | case LOC_REGPARM_ADDR: |
373 | case LOC_LOCAL: | |
0b31a4bc | 374 | return SYMBOL_NEEDS_FRAME; |
c906108c SS |
375 | |
376 | case LOC_UNDEF: | |
377 | case LOC_CONST: | |
378 | case LOC_STATIC: | |
c906108c SS |
379 | case LOC_TYPEDEF: |
380 | ||
381 | case LOC_LABEL: | |
382 | /* Getting the address of a label can be done independently of the block, | |
dda83cd7 SM |
383 | even if some *uses* of that address wouldn't work so well without |
384 | the right frame. */ | |
c906108c SS |
385 | |
386 | case LOC_BLOCK: | |
387 | case LOC_CONST_BYTES: | |
388 | case LOC_UNRESOLVED: | |
389 | case LOC_OPTIMIZED_OUT: | |
0b31a4bc | 390 | return SYMBOL_NEEDS_NONE; |
c906108c | 391 | } |
0b31a4bc TT |
392 | return SYMBOL_NEEDS_FRAME; |
393 | } | |
394 | ||
395 | /* See value.h. */ | |
396 | ||
397 | int | |
398 | symbol_read_needs_frame (struct symbol *sym) | |
399 | { | |
400 | return symbol_read_needs (sym) == SYMBOL_NEEDS_FRAME; | |
c906108c SS |
401 | } |
402 | ||
19630284 JB |
403 | /* Private data to be used with minsym_lookup_iterator_cb. */ |
404 | ||
405 | struct minsym_lookup_data | |
406 | { | |
407 | /* The name of the minimal symbol we are searching for. */ | |
408 | const char *name; | |
409 | ||
410 | /* The field where the callback should store the minimal symbol | |
411 | if found. It should be initialized to NULL before the search | |
412 | is started. */ | |
3b7344d5 | 413 | struct bound_minimal_symbol result; |
19630284 JB |
414 | }; |
415 | ||
416 | /* A callback function for gdbarch_iterate_over_objfiles_in_search_order. | |
417 | It searches by name for a minimal symbol within the given OBJFILE. | |
418 | The arguments are passed via CB_DATA, which in reality is a pointer | |
419 | to struct minsym_lookup_data. */ | |
420 | ||
421 | static int | |
422 | minsym_lookup_iterator_cb (struct objfile *objfile, void *cb_data) | |
423 | { | |
424 | struct minsym_lookup_data *data = (struct minsym_lookup_data *) cb_data; | |
425 | ||
3b7344d5 | 426 | gdb_assert (data->result.minsym == NULL); |
19630284 JB |
427 | |
428 | data->result = lookup_minimal_symbol (data->name, NULL, objfile); | |
429 | ||
430 | /* The iterator should stop iff a match was found. */ | |
3b7344d5 | 431 | return (data->result.minsym != NULL); |
19630284 JB |
432 | } |
433 | ||
63e43d3a PMR |
434 | /* Given static link expression and the frame it lives in, look for the frame |
435 | the static links points to and return it. Return NULL if we could not find | |
436 | such a frame. */ | |
437 | ||
438 | static struct frame_info * | |
439 | follow_static_link (struct frame_info *frame, | |
440 | const struct dynamic_prop *static_link) | |
441 | { | |
442 | CORE_ADDR upper_frame_base; | |
443 | ||
444 | if (!dwarf2_evaluate_property (static_link, frame, NULL, &upper_frame_base)) | |
445 | return NULL; | |
446 | ||
447 | /* Now climb up the stack frame until we reach the frame we are interested | |
448 | in. */ | |
449 | for (; frame != NULL; frame = get_prev_frame (frame)) | |
450 | { | |
451 | struct symbol *framefunc = get_frame_function (frame); | |
452 | ||
453 | /* Stacks can be quite deep: give the user a chance to stop this. */ | |
454 | QUIT; | |
455 | ||
456 | /* If we don't know how to compute FRAME's base address, don't give up: | |
85102364 | 457 | maybe the frame we are looking for is upper in the stack frame. */ |
63e43d3a | 458 | if (framefunc != NULL |
2091da29 | 459 | && SYMBOL_BLOCK_OPS (framefunc) != NULL |
63e43d3a PMR |
460 | && SYMBOL_BLOCK_OPS (framefunc)->get_frame_base != NULL |
461 | && (SYMBOL_BLOCK_OPS (framefunc)->get_frame_base (framefunc, frame) | |
462 | == upper_frame_base)) | |
463 | break; | |
464 | } | |
465 | ||
466 | return frame; | |
467 | } | |
468 | ||
469 | /* Assuming VAR is a symbol that can be reached from FRAME thanks to lexical | |
470 | rules, look for the frame that is actually hosting VAR and return it. If, | |
471 | for some reason, we found no such frame, return NULL. | |
472 | ||
473 | This kind of computation is necessary to correctly handle lexically nested | |
474 | functions. | |
475 | ||
476 | Note that in some cases, we know what scope VAR comes from but we cannot | |
477 | reach the specific frame that hosts the instance of VAR we are looking for. | |
478 | For backward compatibility purposes (with old compilers), we then look for | |
479 | the first frame that can host it. */ | |
480 | ||
481 | static struct frame_info * | |
482 | get_hosting_frame (struct symbol *var, const struct block *var_block, | |
483 | struct frame_info *frame) | |
484 | { | |
485 | const struct block *frame_block = NULL; | |
486 | ||
487 | if (!symbol_read_needs_frame (var)) | |
488 | return NULL; | |
489 | ||
490 | /* Some symbols for local variables have no block: this happens when they are | |
491 | not produced by a debug information reader, for instance when GDB creates | |
492 | synthetic symbols. Without block information, we must assume they are | |
493 | local to FRAME. In this case, there is nothing to do. */ | |
494 | else if (var_block == NULL) | |
495 | return frame; | |
496 | ||
497 | /* We currently assume that all symbols with a location list need a frame. | |
498 | This is true in practice because selecting the location description | |
499 | requires to compute the CFA, hence requires a frame. However we have | |
500 | tests that embed global/static symbols with null location lists. | |
501 | We want to get <optimized out> instead of <frame required> when evaluating | |
502 | them so return a frame instead of raising an error. */ | |
503 | else if (var_block == block_global_block (var_block) | |
504 | || var_block == block_static_block (var_block)) | |
505 | return frame; | |
506 | ||
507 | /* We have to handle the "my_func::my_local_var" notation. This requires us | |
508 | to look for upper frames when we find no block for the current frame: here | |
509 | and below, handle when frame_block == NULL. */ | |
510 | if (frame != NULL) | |
511 | frame_block = get_frame_block (frame, NULL); | |
512 | ||
513 | /* Climb up the call stack until reaching the frame we are looking for. */ | |
514 | while (frame != NULL && frame_block != var_block) | |
515 | { | |
516 | /* Stacks can be quite deep: give the user a chance to stop this. */ | |
517 | QUIT; | |
518 | ||
519 | if (frame_block == NULL) | |
520 | { | |
521 | frame = get_prev_frame (frame); | |
522 | if (frame == NULL) | |
523 | break; | |
524 | frame_block = get_frame_block (frame, NULL); | |
525 | } | |
526 | ||
527 | /* If we failed to find the proper frame, fallback to the heuristic | |
528 | method below. */ | |
529 | else if (frame_block == block_global_block (frame_block)) | |
530 | { | |
531 | frame = NULL; | |
532 | break; | |
533 | } | |
534 | ||
535 | /* Assuming we have a block for this frame: if we are at the function | |
536 | level, the immediate upper lexical block is in an outer function: | |
537 | follow the static link. */ | |
538 | else if (BLOCK_FUNCTION (frame_block)) | |
539 | { | |
540 | const struct dynamic_prop *static_link | |
541 | = block_static_link (frame_block); | |
542 | int could_climb_up = 0; | |
543 | ||
544 | if (static_link != NULL) | |
545 | { | |
546 | frame = follow_static_link (frame, static_link); | |
547 | if (frame != NULL) | |
548 | { | |
549 | frame_block = get_frame_block (frame, NULL); | |
550 | could_climb_up = frame_block != NULL; | |
551 | } | |
552 | } | |
553 | if (!could_climb_up) | |
554 | { | |
555 | frame = NULL; | |
556 | break; | |
557 | } | |
558 | } | |
559 | ||
560 | else | |
561 | /* We must be in some function nested lexical block. Just get the | |
562 | outer block: both must share the same frame. */ | |
563 | frame_block = BLOCK_SUPERBLOCK (frame_block); | |
564 | } | |
565 | ||
566 | /* Old compilers may not provide a static link, or they may provide an | |
567 | invalid one. For such cases, fallback on the old way to evaluate | |
568 | non-local references: just climb up the call stack and pick the first | |
569 | frame that contains the variable we are looking for. */ | |
570 | if (frame == NULL) | |
571 | { | |
572 | frame = block_innermost_frame (var_block); | |
573 | if (frame == NULL) | |
574 | { | |
575 | if (BLOCK_FUNCTION (var_block) | |
576 | && !block_inlined_p (var_block) | |
987012b8 | 577 | && BLOCK_FUNCTION (var_block)->print_name ()) |
63e43d3a | 578 | error (_("No frame is currently executing in block %s."), |
987012b8 | 579 | BLOCK_FUNCTION (var_block)->print_name ()); |
63e43d3a PMR |
580 | else |
581 | error (_("No frame is currently executing in specified" | |
582 | " block")); | |
583 | } | |
584 | } | |
585 | ||
586 | return frame; | |
587 | } | |
588 | ||
15e5fd35 | 589 | /* See language.h. */ |
c906108c | 590 | |
3d6d86c6 | 591 | struct value * |
15e5fd35 AB |
592 | language_defn::read_var_value (struct symbol *var, |
593 | const struct block *var_block, | |
594 | struct frame_info *frame) const | |
c906108c | 595 | { |
52f0bd74 | 596 | struct value *v; |
c906108c SS |
597 | struct type *type = SYMBOL_TYPE (var); |
598 | CORE_ADDR addr; | |
0b31a4bc | 599 | enum symbol_needs_kind sym_need; |
c906108c | 600 | |
41e8491f JK |
601 | /* Call check_typedef on our type to make sure that, if TYPE is |
602 | a TYPE_CODE_TYPEDEF, its length is set to the length of the target type | |
603 | instead of zero. However, we do not replace the typedef type by the | |
604 | target type, because we want to keep the typedef in order to be able to | |
605 | set the returned value type description correctly. */ | |
606 | check_typedef (type); | |
c906108c | 607 | |
0b31a4bc TT |
608 | sym_need = symbol_read_needs (var); |
609 | if (sym_need == SYMBOL_NEEDS_FRAME) | |
63e43d3a | 610 | gdb_assert (frame != NULL); |
9dccd06e | 611 | else if (sym_need == SYMBOL_NEEDS_REGISTERS && !target_has_registers ()) |
987012b8 | 612 | error (_("Cannot read `%s' without registers"), var->print_name ()); |
63e43d3a PMR |
613 | |
614 | if (frame != NULL) | |
615 | frame = get_hosting_frame (var, var_block, frame); | |
c906108c | 616 | |
24d6c2a0 TT |
617 | if (SYMBOL_COMPUTED_OPS (var) != NULL) |
618 | return SYMBOL_COMPUTED_OPS (var)->read_variable (var, frame); | |
619 | ||
c906108c SS |
620 | switch (SYMBOL_CLASS (var)) |
621 | { | |
622 | case LOC_CONST: | |
1612e0c0 SA |
623 | if (is_dynamic_type (type)) |
624 | { | |
625 | /* Value is a constant byte-sequence and needs no memory access. */ | |
b249d2c2 | 626 | type = resolve_dynamic_type (type, {}, /* Unused address. */ 0); |
1612e0c0 SA |
627 | } |
628 | /* Put the constant back in target format. */ | |
41e8491f | 629 | v = allocate_value (type); |
744a8059 | 630 | store_signed_integer (value_contents_raw (v), TYPE_LENGTH (type), |
34877895 | 631 | type_byte_order (type), |
c906108c SS |
632 | (LONGEST) SYMBOL_VALUE (var)); |
633 | VALUE_LVAL (v) = not_lval; | |
634 | return v; | |
635 | ||
636 | case LOC_LABEL: | |
637 | /* Put the constant back in target format. */ | |
41e8491f | 638 | v = allocate_value (type); |
c906108c | 639 | if (overlay_debugging) |
4478b372 | 640 | { |
ebbc3a7d AB |
641 | struct objfile *var_objfile = symbol_objfile (var); |
642 | addr = symbol_overlayed_address (SYMBOL_VALUE_ADDRESS (var), | |
643 | var->obj_section (var_objfile)); | |
990a07ab | 644 | store_typed_address (value_contents_raw (v), type, addr); |
4478b372 | 645 | } |
c906108c | 646 | else |
990a07ab | 647 | store_typed_address (value_contents_raw (v), type, |
4478b372 | 648 | SYMBOL_VALUE_ADDRESS (var)); |
c906108c SS |
649 | VALUE_LVAL (v) = not_lval; |
650 | return v; | |
651 | ||
652 | case LOC_CONST_BYTES: | |
1612e0c0 SA |
653 | if (is_dynamic_type (type)) |
654 | { | |
655 | /* Value is a constant byte-sequence and needs no memory access. */ | |
b249d2c2 | 656 | type = resolve_dynamic_type (type, {}, /* Unused address. */ 0); |
1612e0c0 | 657 | } |
41e8491f | 658 | v = allocate_value (type); |
744a8059 SP |
659 | memcpy (value_contents_raw (v), SYMBOL_VALUE_BYTES (var), |
660 | TYPE_LENGTH (type)); | |
bb9bcb69 MS |
661 | VALUE_LVAL (v) = not_lval; |
662 | return v; | |
c906108c SS |
663 | |
664 | case LOC_STATIC: | |
665 | if (overlay_debugging) | |
ebbc3a7d AB |
666 | addr |
667 | = symbol_overlayed_address (SYMBOL_VALUE_ADDRESS (var), | |
668 | var->obj_section (symbol_objfile (var))); | |
c906108c SS |
669 | else |
670 | addr = SYMBOL_VALUE_ADDRESS (var); | |
671 | break; | |
672 | ||
c906108c | 673 | case LOC_ARG: |
da62e633 | 674 | addr = get_frame_args_address (frame); |
c906108c | 675 | if (!addr) |
8afd712c | 676 | error (_("Unknown argument list address for `%s'."), |
987012b8 | 677 | var->print_name ()); |
c906108c SS |
678 | addr += SYMBOL_VALUE (var); |
679 | break; | |
680 | ||
681 | case LOC_REF_ARG: | |
f76febae AC |
682 | { |
683 | struct value *ref; | |
684 | CORE_ADDR argref; | |
bb9bcb69 | 685 | |
da62e633 | 686 | argref = get_frame_args_address (frame); |
f76febae | 687 | if (!argref) |
8afd712c | 688 | error (_("Unknown argument list address for `%s'."), |
987012b8 | 689 | var->print_name ()); |
f76febae | 690 | argref += SYMBOL_VALUE (var); |
00a4c844 | 691 | ref = value_at (lookup_pointer_type (type), argref); |
1aa20aa8 | 692 | addr = value_as_address (ref); |
f76febae AC |
693 | break; |
694 | } | |
c906108c SS |
695 | |
696 | case LOC_LOCAL: | |
da62e633 | 697 | addr = get_frame_locals_address (frame); |
c906108c SS |
698 | addr += SYMBOL_VALUE (var); |
699 | break; | |
700 | ||
c906108c | 701 | case LOC_TYPEDEF: |
8afd712c | 702 | error (_("Cannot look up value of a typedef `%s'."), |
987012b8 | 703 | var->print_name ()); |
c906108c SS |
704 | break; |
705 | ||
706 | case LOC_BLOCK: | |
707 | if (overlay_debugging) | |
41e8491f | 708 | addr = symbol_overlayed_address |
2b1ffcfd | 709 | (BLOCK_ENTRY_PC (SYMBOL_BLOCK_VALUE (var)), |
ebbc3a7d | 710 | var->obj_section (symbol_objfile (var))); |
c906108c | 711 | else |
2b1ffcfd | 712 | addr = BLOCK_ENTRY_PC (SYMBOL_BLOCK_VALUE (var)); |
41e8491f | 713 | break; |
c906108c SS |
714 | |
715 | case LOC_REGISTER: | |
c906108c SS |
716 | case LOC_REGPARM_ADDR: |
717 | { | |
768a979c UW |
718 | int regno = SYMBOL_REGISTER_OPS (var) |
719 | ->register_number (var, get_frame_arch (frame)); | |
3d6d86c6 | 720 | struct value *regval; |
c906108c | 721 | |
c906108c SS |
722 | if (SYMBOL_CLASS (var) == LOC_REGPARM_ADDR) |
723 | { | |
724 | regval = value_from_register (lookup_pointer_type (type), | |
c5aa993b | 725 | regno, |
c906108c SS |
726 | frame); |
727 | ||
728 | if (regval == NULL) | |
8afd712c | 729 | error (_("Value of register variable not available for `%s'."), |
dda83cd7 | 730 | var->print_name ()); |
c906108c | 731 | |
1aa20aa8 | 732 | addr = value_as_address (regval); |
c906108c SS |
733 | } |
734 | else | |
735 | { | |
736 | regval = value_from_register (type, regno, frame); | |
737 | ||
738 | if (regval == NULL) | |
8afd712c | 739 | error (_("Value of register variable not available for `%s'."), |
dda83cd7 | 740 | var->print_name ()); |
c906108c SS |
741 | return regval; |
742 | } | |
743 | } | |
744 | break; | |
745 | ||
4c2df51b | 746 | case LOC_COMPUTED: |
24d6c2a0 | 747 | gdb_assert_not_reached (_("LOC_COMPUTED variable missing a method")); |
4c2df51b | 748 | |
c906108c SS |
749 | case LOC_UNRESOLVED: |
750 | { | |
19630284 | 751 | struct minsym_lookup_data lookup_data; |
c906108c | 752 | struct minimal_symbol *msym; |
e0740f77 | 753 | struct obj_section *obj_section; |
c906108c | 754 | |
19630284 | 755 | memset (&lookup_data, 0, sizeof (lookup_data)); |
987012b8 | 756 | lookup_data.name = var->linkage_name (); |
19630284 JB |
757 | |
758 | gdbarch_iterate_over_objfiles_in_search_order | |
08be3fe3 | 759 | (symbol_arch (var), |
19630284 | 760 | minsym_lookup_iterator_cb, &lookup_data, |
08be3fe3 | 761 | symbol_objfile (var)); |
3b7344d5 | 762 | msym = lookup_data.result.minsym; |
19630284 | 763 | |
015d2e7e DE |
764 | /* If we can't find the minsym there's a problem in the symbol info. |
765 | The symbol exists in the debug info, but it's missing in the minsym | |
766 | table. */ | |
c906108c | 767 | if (msym == NULL) |
015d2e7e DE |
768 | { |
769 | const char *flavour_name | |
770 | = objfile_flavour_name (symbol_objfile (var)); | |
771 | ||
772 | /* We can't get here unless we've opened the file, so flavour_name | |
773 | can't be NULL. */ | |
774 | gdb_assert (flavour_name != NULL); | |
775 | error (_("Missing %s symbol \"%s\"."), | |
987012b8 | 776 | flavour_name, var->linkage_name ()); |
015d2e7e | 777 | } |
ebbc3a7d | 778 | obj_section = msym->obj_section (lookup_data.result.objfile); |
5382cfab PW |
779 | /* Relocate address, unless there is no section or the variable is |
780 | a TLS variable. */ | |
781 | if (obj_section == NULL | |
782 | || (obj_section->the_bfd_section->flags & SEC_THREAD_LOCAL) != 0) | |
783 | addr = MSYMBOL_VALUE_RAW_ADDRESS (msym); | |
784 | else | |
785 | addr = BMSYMBOL_VALUE_ADDRESS (lookup_data.result); | |
786 | if (overlay_debugging) | |
787 | addr = symbol_overlayed_address (addr, obj_section); | |
788 | /* Determine address of TLS variable. */ | |
e0740f77 JK |
789 | if (obj_section |
790 | && (obj_section->the_bfd_section->flags & SEC_THREAD_LOCAL) != 0) | |
791 | addr = target_translate_tls_address (obj_section->objfile, addr); | |
c906108c SS |
792 | } |
793 | break; | |
794 | ||
795 | case LOC_OPTIMIZED_OUT: | |
42dc7699 | 796 | if (is_dynamic_type (type)) |
b249d2c2 | 797 | type = resolve_dynamic_type (type, {}, /* Unused address. */ 0); |
a7035dbb | 798 | return allocate_optimized_out_value (type); |
c906108c SS |
799 | |
800 | default: | |
8afd712c | 801 | error (_("Cannot look up value of a botched symbol `%s'."), |
987012b8 | 802 | var->print_name ()); |
c906108c SS |
803 | break; |
804 | } | |
805 | ||
08039c9e | 806 | v = value_at_lazy (type, addr); |
c906108c SS |
807 | return v; |
808 | } | |
809 | ||
15e5fd35 | 810 | /* Calls VAR's language read_var_value hook with the given arguments. */ |
a5ee536b JB |
811 | |
812 | struct value * | |
63e43d3a PMR |
813 | read_var_value (struct symbol *var, const struct block *var_block, |
814 | struct frame_info *frame) | |
a5ee536b | 815 | { |
c1b5c1eb | 816 | const struct language_defn *lang = language_def (var->language ()); |
a5ee536b JB |
817 | |
818 | gdb_assert (lang != NULL); | |
a5ee536b | 819 | |
15e5fd35 | 820 | return lang->read_var_value (var, var_block, frame); |
a5ee536b JB |
821 | } |
822 | ||
9acbedc0 UW |
823 | /* Install default attributes for register values. */ |
824 | ||
825 | struct value * | |
2ed3c037 | 826 | default_value_from_register (struct gdbarch *gdbarch, struct type *type, |
dda83cd7 | 827 | int regnum, struct frame_id frame_id) |
9acbedc0 | 828 | { |
9acbedc0 UW |
829 | int len = TYPE_LENGTH (type); |
830 | struct value *value = allocate_value (type); | |
41b56feb | 831 | struct frame_info *frame; |
9acbedc0 UW |
832 | |
833 | VALUE_LVAL (value) = lval_register; | |
41b56feb KB |
834 | frame = frame_find_by_id (frame_id); |
835 | ||
836 | if (frame == NULL) | |
837 | frame_id = null_frame_id; | |
838 | else | |
839 | frame_id = get_frame_id (get_next_frame_sentinel_okay (frame)); | |
840 | ||
841 | VALUE_NEXT_FRAME_ID (value) = frame_id; | |
9acbedc0 UW |
842 | VALUE_REGNUM (value) = regnum; |
843 | ||
844 | /* Any structure stored in more than one register will always be | |
845 | an integral number of registers. Otherwise, you need to do | |
846 | some fiddling with the last register copied here for little | |
847 | endian machines. */ | |
34877895 | 848 | if (type_byte_order (type) == BFD_ENDIAN_BIG |
9acbedc0 UW |
849 | && len < register_size (gdbarch, regnum)) |
850 | /* Big-endian, and we want less than full size. */ | |
851 | set_value_offset (value, register_size (gdbarch, regnum) - len); | |
852 | else | |
853 | set_value_offset (value, 0); | |
854 | ||
855 | return value; | |
856 | } | |
857 | ||
b56d6f31 JB |
858 | /* VALUE must be an lval_register value. If regnum is the value's |
859 | associated register number, and len the length of the values type, | |
860 | read one or more registers in FRAME, starting with register REGNUM, | |
2603f7ee AB |
861 | until we've read LEN bytes. |
862 | ||
863 | If any of the registers we try to read are optimized out, then mark the | |
864 | complete resulting value as optimized out. */ | |
b56d6f31 JB |
865 | |
866 | void | |
867 | read_frame_register_value (struct value *value, struct frame_info *frame) | |
868 | { | |
01efb936 | 869 | struct gdbarch *gdbarch = get_frame_arch (frame); |
6b850546 DT |
870 | LONGEST offset = 0; |
871 | LONGEST reg_offset = value_offset (value); | |
b56d6f31 | 872 | int regnum = VALUE_REGNUM (value); |
3ae385af | 873 | int len = type_length_units (check_typedef (value_type (value))); |
b56d6f31 JB |
874 | |
875 | gdb_assert (VALUE_LVAL (value) == lval_register); | |
876 | ||
01efb936 UW |
877 | /* Skip registers wholly inside of REG_OFFSET. */ |
878 | while (reg_offset >= register_size (gdbarch, regnum)) | |
879 | { | |
880 | reg_offset -= register_size (gdbarch, regnum); | |
881 | regnum++; | |
882 | } | |
883 | ||
884 | /* Copy the data. */ | |
885 | while (len > 0) | |
b56d6f31 JB |
886 | { |
887 | struct value *regval = get_frame_register_value (frame, regnum); | |
3ae385af | 888 | int reg_len = type_length_units (value_type (regval)) - reg_offset; |
b56d6f31 | 889 | |
22355c90 | 890 | /* If the register length is larger than the number of bytes |
dda83cd7 | 891 | remaining to copy, then only copy the appropriate bytes. */ |
01efb936 UW |
892 | if (reg_len > len) |
893 | reg_len = len; | |
22355c90 | 894 | |
01efb936 | 895 | value_contents_copy (value, offset, regval, reg_offset, reg_len); |
b56d6f31 JB |
896 | |
897 | offset += reg_len; | |
01efb936 UW |
898 | len -= reg_len; |
899 | reg_offset = 0; | |
b56d6f31 JB |
900 | regnum++; |
901 | } | |
902 | } | |
903 | ||
00fa51f6 | 904 | /* Return a value of type TYPE, stored in register REGNUM, in frame FRAME. */ |
c906108c | 905 | |
3d6d86c6 | 906 | struct value * |
fba45db2 | 907 | value_from_register (struct type *type, int regnum, struct frame_info *frame) |
c906108c | 908 | { |
ff2e87ac | 909 | struct gdbarch *gdbarch = get_frame_arch (frame); |
9acbedc0 UW |
910 | struct type *type1 = check_typedef (type); |
911 | struct value *v; | |
912 | ||
e9e45075 | 913 | if (gdbarch_convert_register_p (gdbarch, regnum, type1)) |
ff2e87ac | 914 | { |
3543a589 TT |
915 | int optim, unavail, ok; |
916 | ||
ff2e87ac | 917 | /* The ISA/ABI need to something weird when obtaining the |
dda83cd7 SM |
918 | specified value from this register. It might need to |
919 | re-order non-adjacent, starting with REGNUM (see MIPS and | |
920 | i386). It might need to convert the [float] register into | |
921 | the corresponding [integer] type (see Alpha). The assumption | |
922 | is that gdbarch_register_to_value populates the entire value | |
923 | including the location. */ | |
9acbedc0 UW |
924 | v = allocate_value (type); |
925 | VALUE_LVAL (v) = lval_register; | |
41b56feb | 926 | VALUE_NEXT_FRAME_ID (v) = get_frame_id (get_next_frame_sentinel_okay (frame)); |
9acbedc0 | 927 | VALUE_REGNUM (v) = regnum; |
8dccd430 PA |
928 | ok = gdbarch_register_to_value (gdbarch, frame, regnum, type1, |
929 | value_contents_raw (v), &optim, | |
930 | &unavail); | |
3543a589 TT |
931 | |
932 | if (!ok) | |
933 | { | |
934 | if (optim) | |
9a0dc9e3 | 935 | mark_value_bytes_optimized_out (v, 0, TYPE_LENGTH (type)); |
3543a589 TT |
936 | if (unavail) |
937 | mark_value_bytes_unavailable (v, 0, TYPE_LENGTH (type)); | |
938 | } | |
ff2e87ac AC |
939 | } |
940 | else | |
c906108c | 941 | { |
9acbedc0 | 942 | /* Construct the value. */ |
2ed3c037 UW |
943 | v = gdbarch_value_from_register (gdbarch, type, |
944 | regnum, get_frame_id (frame)); | |
00fa51f6 UW |
945 | |
946 | /* Get the data. */ | |
b56d6f31 | 947 | read_frame_register_value (v, frame); |
c906108c | 948 | } |
8dccd430 | 949 | |
c906108c SS |
950 | return v; |
951 | } | |
ff2e87ac | 952 | |
2ed3c037 UW |
953 | /* Return contents of register REGNUM in frame FRAME as address. |
954 | Will abort if register value is not available. */ | |
0b2b0195 UW |
955 | |
956 | CORE_ADDR | |
2ed3c037 | 957 | address_from_register (int regnum, struct frame_info *frame) |
0b2b0195 | 958 | { |
2ed3c037 UW |
959 | struct gdbarch *gdbarch = get_frame_arch (frame); |
960 | struct type *type = builtin_type (gdbarch)->builtin_data_ptr; | |
0b2b0195 UW |
961 | struct value *value; |
962 | CORE_ADDR result; | |
f6efe3f8 | 963 | int regnum_max_excl = gdbarch_num_cooked_regs (gdbarch); |
5f3ff4f8 JK |
964 | |
965 | if (regnum < 0 || regnum >= regnum_max_excl) | |
966 | error (_("Invalid register #%d, expecting 0 <= # < %d"), regnum, | |
967 | regnum_max_excl); | |
0b2b0195 | 968 | |
2ed3c037 UW |
969 | /* This routine may be called during early unwinding, at a time |
970 | where the ID of FRAME is not yet known. Calling value_from_register | |
971 | would therefore abort in get_frame_id. However, since we only need | |
972 | a temporary value that is never used as lvalue, we actually do not | |
41b56feb | 973 | really need to set its VALUE_NEXT_FRAME_ID. Therefore, we re-implement |
eeef931a | 974 | the core of value_from_register, but use the null_frame_id. */ |
2ed3c037 | 975 | |
eeef931a UW |
976 | /* Some targets require a special conversion routine even for plain |
977 | pointer types. Avoid constructing a value object in those cases. */ | |
978 | if (gdbarch_convert_register_p (gdbarch, regnum, type)) | |
979 | { | |
224c3ddb | 980 | gdb_byte *buf = (gdb_byte *) alloca (TYPE_LENGTH (type)); |
eeef931a UW |
981 | int optim, unavail, ok; |
982 | ||
983 | ok = gdbarch_register_to_value (gdbarch, frame, regnum, type, | |
984 | buf, &optim, &unavail); | |
985 | if (!ok) | |
986 | { | |
987 | /* This function is used while computing a location expression. | |
988 | Complain about the value being optimized out, rather than | |
989 | letting value_as_address complain about some random register | |
990 | the expression depends on not being saved. */ | |
991 | error_value_optimized_out (); | |
992 | } | |
993 | ||
994 | return unpack_long (type, buf); | |
995 | } | |
2ed3c037 UW |
996 | |
997 | value = gdbarch_value_from_register (gdbarch, type, regnum, null_frame_id); | |
998 | read_frame_register_value (value, frame); | |
0b2b0195 | 999 | |
901461f8 PA |
1000 | if (value_optimized_out (value)) |
1001 | { | |
1002 | /* This function is used while computing a location expression. | |
1003 | Complain about the value being optimized out, rather than | |
1004 | letting value_as_address complain about some random register | |
1005 | the expression depends on not being saved. */ | |
1006 | error_value_optimized_out (); | |
1007 | } | |
1008 | ||
0b2b0195 UW |
1009 | result = value_as_address (value); |
1010 | release_value (value); | |
0b2b0195 UW |
1011 | |
1012 | return result; | |
1013 | } | |
b56d6f31 | 1014 | |
b057297a AH |
1015 | #if GDB_SELF_TEST |
1016 | namespace selftests { | |
1017 | namespace findvar_tests { | |
1018 | ||
1019 | /* Function to test copy_integer_to_size. Store SOURCE_VAL with size | |
1020 | SOURCE_SIZE to a buffer, making sure no sign extending happens at this | |
1021 | stage. Copy buffer to a new buffer using copy_integer_to_size. Extract | |
1022 | copied value and compare to DEST_VALU. Copy again with a signed | |
1023 | copy_integer_to_size and compare to DEST_VALS. Do everything for both | |
1024 | LITTLE and BIG target endians. Use unsigned values throughout to make | |
1025 | sure there are no implicit sign extensions. */ | |
1026 | ||
1027 | static void | |
1028 | do_cint_test (ULONGEST dest_valu, ULONGEST dest_vals, int dest_size, | |
1029 | ULONGEST src_val, int src_size) | |
1030 | { | |
1031 | for (int i = 0; i < 2 ; i++) | |
1032 | { | |
1033 | gdb_byte srcbuf[sizeof (ULONGEST)] = {}; | |
1034 | gdb_byte destbuf[sizeof (ULONGEST)] = {}; | |
1035 | enum bfd_endian byte_order = i ? BFD_ENDIAN_BIG : BFD_ENDIAN_LITTLE; | |
1036 | ||
1037 | /* Fill the src buffer (and later the dest buffer) with non-zero junk, | |
1038 | to ensure zero extensions aren't hidden. */ | |
1039 | memset (srcbuf, 0xaa, sizeof (srcbuf)); | |
1040 | ||
1041 | /* Store (and later extract) using unsigned to ensure there are no sign | |
1042 | extensions. */ | |
1043 | store_unsigned_integer (srcbuf, src_size, byte_order, src_val); | |
1044 | ||
1045 | /* Test unsigned. */ | |
1046 | memset (destbuf, 0xaa, sizeof (destbuf)); | |
1047 | copy_integer_to_size (destbuf, dest_size, srcbuf, src_size, false, | |
1048 | byte_order); | |
1049 | SELF_CHECK (dest_valu == extract_unsigned_integer (destbuf, dest_size, | |
1050 | byte_order)); | |
1051 | ||
1052 | /* Test signed. */ | |
1053 | memset (destbuf, 0xaa, sizeof (destbuf)); | |
1054 | copy_integer_to_size (destbuf, dest_size, srcbuf, src_size, true, | |
1055 | byte_order); | |
1056 | SELF_CHECK (dest_vals == extract_unsigned_integer (destbuf, dest_size, | |
1057 | byte_order)); | |
1058 | } | |
1059 | } | |
1060 | ||
1061 | static void | |
1062 | copy_integer_to_size_test () | |
1063 | { | |
1064 | /* Destination is bigger than the source, which has the signed bit unset. */ | |
1065 | do_cint_test (0x12345678, 0x12345678, 8, 0x12345678, 4); | |
1066 | do_cint_test (0x345678, 0x345678, 8, 0x12345678, 3); | |
1067 | ||
1068 | /* Destination is bigger than the source, which has the signed bit set. */ | |
1069 | do_cint_test (0xdeadbeef, 0xffffffffdeadbeef, 8, 0xdeadbeef, 4); | |
1070 | do_cint_test (0xadbeef, 0xffffffffffadbeef, 8, 0xdeadbeef, 3); | |
1071 | ||
1072 | /* Destination is smaller than the source. */ | |
1073 | do_cint_test (0x5678, 0x5678, 2, 0x12345678, 3); | |
1074 | do_cint_test (0xbeef, 0xbeef, 2, 0xdeadbeef, 3); | |
1075 | ||
1076 | /* Destination and source are the same size. */ | |
1077 | do_cint_test (0x8765432112345678, 0x8765432112345678, 8, 0x8765432112345678, | |
1078 | 8); | |
1079 | do_cint_test (0x432112345678, 0x432112345678, 6, 0x8765432112345678, 6); | |
1080 | do_cint_test (0xfeedbeaddeadbeef, 0xfeedbeaddeadbeef, 8, 0xfeedbeaddeadbeef, | |
1081 | 8); | |
1082 | do_cint_test (0xbeaddeadbeef, 0xbeaddeadbeef, 6, 0xfeedbeaddeadbeef, 6); | |
1083 | ||
1084 | /* Destination is bigger than the source. Source is bigger than 32bits. */ | |
1085 | do_cint_test (0x3412345678, 0x3412345678, 8, 0x3412345678, 6); | |
1086 | do_cint_test (0xff12345678, 0xff12345678, 8, 0xff12345678, 6); | |
1087 | do_cint_test (0x432112345678, 0x432112345678, 8, 0x8765432112345678, 6); | |
1088 | do_cint_test (0xff2112345678, 0xffffff2112345678, 8, 0xffffff2112345678, 6); | |
1089 | } | |
1090 | ||
1091 | } // namespace findvar_test | |
1092 | } // namespace selftests | |
1093 | ||
1094 | #endif | |
1095 | ||
6c265988 | 1096 | void _initialize_findvar (); |
b057297a | 1097 | void |
6c265988 | 1098 | _initialize_findvar () |
b057297a AH |
1099 | { |
1100 | #if GDB_SELF_TEST | |
1526853e SM |
1101 | selftests::register_test |
1102 | ("copy_integer_to_size", | |
1103 | selftests::findvar_tests::copy_integer_to_size_test); | |
b057297a AH |
1104 | #endif |
1105 | } |