Commit | Line | Data |
---|---|---|
c906108c | 1 | /* Find a variable's value in memory, for GDB, the GNU debugger. |
b6ba6518 KB |
2 | Copyright 1986, 1987, 1988, 1989, 1990, 1991, 1992, 1993, 1994, 1995, |
3 | 1996, 1997, 1998, 1999, 2000, 2001 | |
c906108c SS |
4 | Free Software Foundation, Inc. |
5 | ||
c5aa993b | 6 | This file is part of GDB. |
c906108c | 7 | |
c5aa993b JM |
8 | This program is free software; you can redistribute it and/or modify |
9 | it under the terms of the GNU General Public License as published by | |
10 | the Free Software Foundation; either version 2 of the License, or | |
11 | (at your option) any later version. | |
c906108c | 12 | |
c5aa993b JM |
13 | This program is distributed in the hope that it will be useful, |
14 | but WITHOUT ANY WARRANTY; without even the implied warranty of | |
15 | MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the | |
16 | GNU General Public License for more details. | |
c906108c | 17 | |
c5aa993b JM |
18 | You should have received a copy of the GNU General Public License |
19 | along with this program; if not, write to the Free Software | |
20 | Foundation, Inc., 59 Temple Place - Suite 330, | |
21 | Boston, MA 02111-1307, USA. */ | |
c906108c SS |
22 | |
23 | #include "defs.h" | |
24 | #include "symtab.h" | |
25 | #include "gdbtypes.h" | |
26 | #include "frame.h" | |
27 | #include "value.h" | |
28 | #include "gdbcore.h" | |
29 | #include "inferior.h" | |
30 | #include "target.h" | |
31 | #include "gdb_string.h" | |
14e534aa | 32 | #include "gdb_assert.h" |
c906108c | 33 | #include "floatformat.h" |
c5aa993b | 34 | #include "symfile.h" /* for overlay functions */ |
4e052eda | 35 | #include "regcache.h" |
c906108c SS |
36 | |
37 | /* This is used to indicate that we don't know the format of the floating point | |
38 | number. Typically, this is useful for native ports, where the actual format | |
39 | is irrelevant, since no conversions will be taking place. */ | |
40 | ||
41 | const struct floatformat floatformat_unknown; | |
42 | ||
c906108c SS |
43 | /* Basic byte-swapping routines. GDB has needed these for a long time... |
44 | All extract a target-format integer at ADDR which is LEN bytes long. */ | |
45 | ||
46 | #if TARGET_CHAR_BIT != 8 || HOST_CHAR_BIT != 8 | |
47 | /* 8 bit characters are a pretty safe assumption these days, so we | |
48 | assume it throughout all these swapping routines. If we had to deal with | |
49 | 9 bit characters, we would need to make len be in bits and would have | |
50 | to re-write these routines... */ | |
c5aa993b | 51 | you lose |
c906108c SS |
52 | #endif |
53 | ||
a9ac8f51 AC |
54 | LONGEST |
55 | extract_signed_integer (void *addr, int len) | |
c906108c SS |
56 | { |
57 | LONGEST retval; | |
58 | unsigned char *p; | |
c5aa993b | 59 | unsigned char *startaddr = (unsigned char *) addr; |
c906108c SS |
60 | unsigned char *endaddr = startaddr + len; |
61 | ||
62 | if (len > (int) sizeof (LONGEST)) | |
63 | error ("\ | |
64 | That operation is not available on integers of more than %d bytes.", | |
65 | sizeof (LONGEST)); | |
66 | ||
67 | /* Start at the most significant end of the integer, and work towards | |
68 | the least significant. */ | |
d7449b42 | 69 | if (TARGET_BYTE_ORDER == BFD_ENDIAN_BIG) |
c906108c SS |
70 | { |
71 | p = startaddr; | |
72 | /* Do the sign extension once at the start. */ | |
c5aa993b | 73 | retval = ((LONGEST) * p ^ 0x80) - 0x80; |
c906108c SS |
74 | for (++p; p < endaddr; ++p) |
75 | retval = (retval << 8) | *p; | |
76 | } | |
77 | else | |
78 | { | |
79 | p = endaddr - 1; | |
80 | /* Do the sign extension once at the start. */ | |
c5aa993b | 81 | retval = ((LONGEST) * p ^ 0x80) - 0x80; |
c906108c SS |
82 | for (--p; p >= startaddr; --p) |
83 | retval = (retval << 8) | *p; | |
84 | } | |
85 | return retval; | |
86 | } | |
87 | ||
88 | ULONGEST | |
a9ac8f51 | 89 | extract_unsigned_integer (void *addr, int len) |
c906108c SS |
90 | { |
91 | ULONGEST retval; | |
92 | unsigned char *p; | |
c5aa993b | 93 | unsigned char *startaddr = (unsigned char *) addr; |
c906108c SS |
94 | unsigned char *endaddr = startaddr + len; |
95 | ||
96 | if (len > (int) sizeof (ULONGEST)) | |
97 | error ("\ | |
98 | That operation is not available on integers of more than %d bytes.", | |
99 | sizeof (ULONGEST)); | |
100 | ||
101 | /* Start at the most significant end of the integer, and work towards | |
102 | the least significant. */ | |
103 | retval = 0; | |
d7449b42 | 104 | if (TARGET_BYTE_ORDER == BFD_ENDIAN_BIG) |
c906108c SS |
105 | { |
106 | for (p = startaddr; p < endaddr; ++p) | |
107 | retval = (retval << 8) | *p; | |
108 | } | |
109 | else | |
110 | { | |
111 | for (p = endaddr - 1; p >= startaddr; --p) | |
112 | retval = (retval << 8) | *p; | |
113 | } | |
114 | return retval; | |
115 | } | |
116 | ||
117 | /* Sometimes a long long unsigned integer can be extracted as a | |
118 | LONGEST value. This is done so that we can print these values | |
119 | better. If this integer can be converted to a LONGEST, this | |
120 | function returns 1 and sets *PVAL. Otherwise it returns 0. */ | |
121 | ||
122 | int | |
a9ac8f51 | 123 | extract_long_unsigned_integer (void *addr, int orig_len, LONGEST *pval) |
c906108c SS |
124 | { |
125 | char *p, *first_addr; | |
126 | int len; | |
127 | ||
128 | len = orig_len; | |
d7449b42 | 129 | if (TARGET_BYTE_ORDER == BFD_ENDIAN_BIG) |
c906108c SS |
130 | { |
131 | for (p = (char *) addr; | |
132 | len > (int) sizeof (LONGEST) && p < (char *) addr + orig_len; | |
133 | p++) | |
134 | { | |
135 | if (*p == 0) | |
136 | len--; | |
137 | else | |
138 | break; | |
139 | } | |
140 | first_addr = p; | |
141 | } | |
142 | else | |
143 | { | |
144 | first_addr = (char *) addr; | |
145 | for (p = (char *) addr + orig_len - 1; | |
146 | len > (int) sizeof (LONGEST) && p >= (char *) addr; | |
147 | p--) | |
148 | { | |
149 | if (*p == 0) | |
150 | len--; | |
151 | else | |
152 | break; | |
153 | } | |
154 | } | |
155 | ||
156 | if (len <= (int) sizeof (LONGEST)) | |
157 | { | |
158 | *pval = (LONGEST) extract_unsigned_integer (first_addr, | |
159 | sizeof (LONGEST)); | |
160 | return 1; | |
161 | } | |
162 | ||
163 | return 0; | |
164 | } | |
165 | ||
4478b372 JB |
166 | |
167 | /* Treat the LEN bytes at ADDR as a target-format address, and return | |
168 | that address. ADDR is a buffer in the GDB process, not in the | |
169 | inferior. | |
170 | ||
171 | This function should only be used by target-specific code. It | |
172 | assumes that a pointer has the same representation as that thing's | |
173 | address represented as an integer. Some machines use word | |
174 | addresses, or similarly munged things, for certain types of | |
175 | pointers, so that assumption doesn't hold everywhere. | |
176 | ||
177 | Common code should use extract_typed_address instead, or something | |
178 | else based on POINTER_TO_ADDRESS. */ | |
179 | ||
c906108c | 180 | CORE_ADDR |
a9ac8f51 | 181 | extract_address (void *addr, int len) |
c906108c SS |
182 | { |
183 | /* Assume a CORE_ADDR can fit in a LONGEST (for now). Not sure | |
184 | whether we want this to be true eventually. */ | |
c5aa993b | 185 | return (CORE_ADDR) extract_unsigned_integer (addr, len); |
c906108c SS |
186 | } |
187 | ||
4478b372 | 188 | |
4478b372 JB |
189 | /* Treat the bytes at BUF as a pointer of type TYPE, and return the |
190 | address it represents. */ | |
191 | CORE_ADDR | |
192 | extract_typed_address (void *buf, struct type *type) | |
193 | { | |
194 | if (TYPE_CODE (type) != TYPE_CODE_PTR | |
195 | && TYPE_CODE (type) != TYPE_CODE_REF) | |
8e65ff28 AC |
196 | internal_error (__FILE__, __LINE__, |
197 | "extract_typed_address: " | |
4478b372 JB |
198 | "type is not a pointer or reference"); |
199 | ||
200 | return POINTER_TO_ADDRESS (type, buf); | |
201 | } | |
202 | ||
203 | ||
c906108c | 204 | void |
a9ac8f51 | 205 | store_signed_integer (void *addr, int len, LONGEST val) |
c906108c SS |
206 | { |
207 | unsigned char *p; | |
c5aa993b | 208 | unsigned char *startaddr = (unsigned char *) addr; |
c906108c SS |
209 | unsigned char *endaddr = startaddr + len; |
210 | ||
211 | /* Start at the least significant end of the integer, and work towards | |
212 | the most significant. */ | |
d7449b42 | 213 | if (TARGET_BYTE_ORDER == BFD_ENDIAN_BIG) |
c906108c SS |
214 | { |
215 | for (p = endaddr - 1; p >= startaddr; --p) | |
216 | { | |
217 | *p = val & 0xff; | |
218 | val >>= 8; | |
219 | } | |
220 | } | |
221 | else | |
222 | { | |
223 | for (p = startaddr; p < endaddr; ++p) | |
224 | { | |
225 | *p = val & 0xff; | |
226 | val >>= 8; | |
227 | } | |
228 | } | |
229 | } | |
230 | ||
231 | void | |
a9ac8f51 | 232 | store_unsigned_integer (void *addr, int len, ULONGEST val) |
c906108c SS |
233 | { |
234 | unsigned char *p; | |
c5aa993b | 235 | unsigned char *startaddr = (unsigned char *) addr; |
c906108c SS |
236 | unsigned char *endaddr = startaddr + len; |
237 | ||
238 | /* Start at the least significant end of the integer, and work towards | |
239 | the most significant. */ | |
d7449b42 | 240 | if (TARGET_BYTE_ORDER == BFD_ENDIAN_BIG) |
c906108c SS |
241 | { |
242 | for (p = endaddr - 1; p >= startaddr; --p) | |
243 | { | |
244 | *p = val & 0xff; | |
245 | val >>= 8; | |
246 | } | |
247 | } | |
248 | else | |
249 | { | |
250 | for (p = startaddr; p < endaddr; ++p) | |
251 | { | |
252 | *p = val & 0xff; | |
253 | val >>= 8; | |
254 | } | |
255 | } | |
256 | } | |
257 | ||
4478b372 JB |
258 | /* Store the address VAL as a LEN-byte value in target byte order at |
259 | ADDR. ADDR is a buffer in the GDB process, not in the inferior. | |
260 | ||
261 | This function should only be used by target-specific code. It | |
262 | assumes that a pointer has the same representation as that thing's | |
263 | address represented as an integer. Some machines use word | |
264 | addresses, or similarly munged things, for certain types of | |
265 | pointers, so that assumption doesn't hold everywhere. | |
266 | ||
267 | Common code should use store_typed_address instead, or something else | |
268 | based on ADDRESS_TO_POINTER. */ | |
c906108c | 269 | void |
a9ac8f51 | 270 | store_address (void *addr, int len, LONGEST val) |
c906108c | 271 | { |
c906108c SS |
272 | store_unsigned_integer (addr, len, val); |
273 | } | |
4478b372 JB |
274 | |
275 | ||
4478b372 JB |
276 | /* Store the address ADDR as a pointer of type TYPE at BUF, in target |
277 | form. */ | |
278 | void | |
279 | store_typed_address (void *buf, struct type *type, CORE_ADDR addr) | |
280 | { | |
281 | if (TYPE_CODE (type) != TYPE_CODE_PTR | |
282 | && TYPE_CODE (type) != TYPE_CODE_REF) | |
8e65ff28 AC |
283 | internal_error (__FILE__, __LINE__, |
284 | "store_typed_address: " | |
4478b372 JB |
285 | "type is not a pointer or reference"); |
286 | ||
287 | ADDRESS_TO_POINTER (type, buf, addr); | |
288 | } | |
289 | ||
290 | ||
291 | ||
c906108c SS |
292 | /* Return a `value' with the contents of register REGNUM |
293 | in its virtual format, with the type specified by | |
294 | REGISTER_VIRTUAL_TYPE. | |
295 | ||
296 | NOTE: returns NULL if register value is not available. | |
297 | Caller will check return value or die! */ | |
298 | ||
3d6d86c6 | 299 | struct value * |
fba45db2 | 300 | value_of_register (int regnum) |
c906108c SS |
301 | { |
302 | CORE_ADDR addr; | |
303 | int optim; | |
3d6d86c6 | 304 | struct value *reg_val; |
e6cbd02a | 305 | char *raw_buffer = (char*) alloca (MAX_REGISTER_RAW_SIZE); |
c906108c SS |
306 | enum lval_type lval; |
307 | ||
308 | get_saved_register (raw_buffer, &optim, &addr, | |
309 | selected_frame, regnum, &lval); | |
310 | ||
32178cab | 311 | if (register_cached (regnum) < 0) |
c5aa993b | 312 | return NULL; /* register value not available */ |
c906108c SS |
313 | |
314 | reg_val = allocate_value (REGISTER_VIRTUAL_TYPE (regnum)); | |
315 | ||
316 | /* Convert raw data to virtual format if necessary. */ | |
317 | ||
c906108c SS |
318 | if (REGISTER_CONVERTIBLE (regnum)) |
319 | { | |
320 | REGISTER_CONVERT_TO_VIRTUAL (regnum, REGISTER_VIRTUAL_TYPE (regnum), | |
321 | raw_buffer, VALUE_CONTENTS_RAW (reg_val)); | |
322 | } | |
392a587b JM |
323 | else if (REGISTER_RAW_SIZE (regnum) == REGISTER_VIRTUAL_SIZE (regnum)) |
324 | memcpy (VALUE_CONTENTS_RAW (reg_val), raw_buffer, | |
325 | REGISTER_RAW_SIZE (regnum)); | |
c906108c | 326 | else |
8e65ff28 AC |
327 | internal_error (__FILE__, __LINE__, |
328 | "Register \"%s\" (%d) has conflicting raw (%d) and virtual (%d) size", | |
96baa820 JM |
329 | REGISTER_NAME (regnum), |
330 | regnum, | |
331 | REGISTER_RAW_SIZE (regnum), | |
332 | REGISTER_VIRTUAL_SIZE (regnum)); | |
c906108c SS |
333 | VALUE_LVAL (reg_val) = lval; |
334 | VALUE_ADDRESS (reg_val) = addr; | |
335 | VALUE_REGNO (reg_val) = regnum; | |
336 | VALUE_OPTIMIZED_OUT (reg_val) = optim; | |
337 | return reg_val; | |
338 | } | |
4478b372 JB |
339 | |
340 | /* Given a pointer of type TYPE in target form in BUF, return the | |
341 | address it represents. */ | |
342 | CORE_ADDR | |
ac2e2ef7 | 343 | unsigned_pointer_to_address (struct type *type, void *buf) |
4478b372 JB |
344 | { |
345 | return extract_address (buf, TYPE_LENGTH (type)); | |
346 | } | |
347 | ||
ac2e2ef7 AC |
348 | CORE_ADDR |
349 | signed_pointer_to_address (struct type *type, void *buf) | |
350 | { | |
351 | return extract_signed_integer (buf, TYPE_LENGTH (type)); | |
352 | } | |
4478b372 JB |
353 | |
354 | /* Given an address, store it as a pointer of type TYPE in target | |
355 | format in BUF. */ | |
356 | void | |
ac2e2ef7 | 357 | unsigned_address_to_pointer (struct type *type, void *buf, CORE_ADDR addr) |
4478b372 JB |
358 | { |
359 | store_address (buf, TYPE_LENGTH (type), addr); | |
360 | } | |
361 | ||
ac2e2ef7 AC |
362 | void |
363 | address_to_signed_pointer (struct type *type, void *buf, CORE_ADDR addr) | |
364 | { | |
365 | store_signed_integer (buf, TYPE_LENGTH (type), addr); | |
366 | } | |
c906108c SS |
367 | \f |
368 | /* Will calling read_var_value or locate_var_value on SYM end | |
369 | up caring what frame it is being evaluated relative to? SYM must | |
370 | be non-NULL. */ | |
371 | int | |
fba45db2 | 372 | symbol_read_needs_frame (struct symbol *sym) |
c906108c SS |
373 | { |
374 | switch (SYMBOL_CLASS (sym)) | |
375 | { | |
376 | /* All cases listed explicitly so that gcc -Wall will detect it if | |
c5aa993b | 377 | we failed to consider one. */ |
c906108c SS |
378 | case LOC_REGISTER: |
379 | case LOC_ARG: | |
380 | case LOC_REF_ARG: | |
381 | case LOC_REGPARM: | |
382 | case LOC_REGPARM_ADDR: | |
383 | case LOC_LOCAL: | |
384 | case LOC_LOCAL_ARG: | |
385 | case LOC_BASEREG: | |
386 | case LOC_BASEREG_ARG: | |
387 | case LOC_THREAD_LOCAL_STATIC: | |
388 | return 1; | |
389 | ||
390 | case LOC_UNDEF: | |
391 | case LOC_CONST: | |
392 | case LOC_STATIC: | |
393 | case LOC_INDIRECT: | |
394 | case LOC_TYPEDEF: | |
395 | ||
396 | case LOC_LABEL: | |
397 | /* Getting the address of a label can be done independently of the block, | |
c5aa993b JM |
398 | even if some *uses* of that address wouldn't work so well without |
399 | the right frame. */ | |
c906108c SS |
400 | |
401 | case LOC_BLOCK: | |
402 | case LOC_CONST_BYTES: | |
403 | case LOC_UNRESOLVED: | |
404 | case LOC_OPTIMIZED_OUT: | |
405 | return 0; | |
406 | } | |
407 | return 1; | |
408 | } | |
409 | ||
410 | /* Given a struct symbol for a variable, | |
411 | and a stack frame id, read the value of the variable | |
412 | and return a (pointer to a) struct value containing the value. | |
413 | If the variable cannot be found, return a zero pointer. | |
414 | If FRAME is NULL, use the selected_frame. */ | |
415 | ||
3d6d86c6 | 416 | struct value * |
fba45db2 | 417 | read_var_value (register struct symbol *var, struct frame_info *frame) |
c906108c | 418 | { |
3d6d86c6 | 419 | register struct value *v; |
c906108c SS |
420 | struct type *type = SYMBOL_TYPE (var); |
421 | CORE_ADDR addr; | |
422 | register int len; | |
423 | ||
424 | v = allocate_value (type); | |
425 | VALUE_LVAL (v) = lval_memory; /* The most likely possibility. */ | |
426 | VALUE_BFD_SECTION (v) = SYMBOL_BFD_SECTION (var); | |
427 | ||
428 | len = TYPE_LENGTH (type); | |
429 | ||
c5aa993b JM |
430 | if (frame == NULL) |
431 | frame = selected_frame; | |
c906108c SS |
432 | |
433 | switch (SYMBOL_CLASS (var)) | |
434 | { | |
435 | case LOC_CONST: | |
436 | /* Put the constant back in target format. */ | |
437 | store_signed_integer (VALUE_CONTENTS_RAW (v), len, | |
438 | (LONGEST) SYMBOL_VALUE (var)); | |
439 | VALUE_LVAL (v) = not_lval; | |
440 | return v; | |
441 | ||
442 | case LOC_LABEL: | |
443 | /* Put the constant back in target format. */ | |
444 | if (overlay_debugging) | |
4478b372 JB |
445 | { |
446 | CORE_ADDR addr | |
447 | = symbol_overlayed_address (SYMBOL_VALUE_ADDRESS (var), | |
448 | SYMBOL_BFD_SECTION (var)); | |
449 | store_typed_address (VALUE_CONTENTS_RAW (v), type, addr); | |
450 | } | |
c906108c | 451 | else |
4478b372 JB |
452 | store_typed_address (VALUE_CONTENTS_RAW (v), type, |
453 | SYMBOL_VALUE_ADDRESS (var)); | |
c906108c SS |
454 | VALUE_LVAL (v) = not_lval; |
455 | return v; | |
456 | ||
457 | case LOC_CONST_BYTES: | |
458 | { | |
459 | char *bytes_addr; | |
460 | bytes_addr = SYMBOL_VALUE_BYTES (var); | |
461 | memcpy (VALUE_CONTENTS_RAW (v), bytes_addr, len); | |
462 | VALUE_LVAL (v) = not_lval; | |
463 | return v; | |
464 | } | |
465 | ||
466 | case LOC_STATIC: | |
467 | if (overlay_debugging) | |
468 | addr = symbol_overlayed_address (SYMBOL_VALUE_ADDRESS (var), | |
469 | SYMBOL_BFD_SECTION (var)); | |
470 | else | |
471 | addr = SYMBOL_VALUE_ADDRESS (var); | |
472 | break; | |
473 | ||
474 | case LOC_INDIRECT: | |
f76febae AC |
475 | { |
476 | /* The import slot does not have a real address in it from the | |
477 | dynamic loader (dld.sl on HP-UX), if the target hasn't | |
478 | begun execution yet, so check for that. */ | |
479 | CORE_ADDR locaddr; | |
480 | struct value *loc; | |
481 | if (!target_has_execution) | |
482 | error ("\ | |
c906108c SS |
483 | Attempt to access variable defined in different shared object or load module when\n\ |
484 | addresses have not been bound by the dynamic loader. Try again when executable is running."); | |
c5aa993b | 485 | |
f76febae AC |
486 | locaddr = SYMBOL_VALUE_ADDRESS (var); |
487 | loc = value_at (lookup_pointer_type (type), locaddr, NULL); | |
1aa20aa8 | 488 | addr = value_as_address (loc); |
f76febae | 489 | } |
c906108c SS |
490 | |
491 | case LOC_ARG: | |
492 | if (frame == NULL) | |
493 | return 0; | |
494 | addr = FRAME_ARGS_ADDRESS (frame); | |
495 | if (!addr) | |
496 | return 0; | |
497 | addr += SYMBOL_VALUE (var); | |
498 | break; | |
499 | ||
500 | case LOC_REF_ARG: | |
f76febae AC |
501 | { |
502 | struct value *ref; | |
503 | CORE_ADDR argref; | |
504 | if (frame == NULL) | |
505 | return 0; | |
506 | argref = FRAME_ARGS_ADDRESS (frame); | |
507 | if (!argref) | |
508 | return 0; | |
509 | argref += SYMBOL_VALUE (var); | |
510 | ref = value_at (lookup_pointer_type (type), argref, NULL); | |
1aa20aa8 | 511 | addr = value_as_address (ref); |
f76febae AC |
512 | break; |
513 | } | |
c906108c SS |
514 | |
515 | case LOC_LOCAL: | |
516 | case LOC_LOCAL_ARG: | |
517 | if (frame == NULL) | |
518 | return 0; | |
519 | addr = FRAME_LOCALS_ADDRESS (frame); | |
520 | addr += SYMBOL_VALUE (var); | |
521 | break; | |
522 | ||
523 | case LOC_BASEREG: | |
524 | case LOC_BASEREG_ARG: | |
c906108c SS |
525 | case LOC_THREAD_LOCAL_STATIC: |
526 | { | |
3d6d86c6 | 527 | struct value *regval; |
c5aa993b | 528 | |
9ed10b08 ND |
529 | regval = value_from_register (lookup_pointer_type (type), |
530 | SYMBOL_BASEREG (var), frame); | |
531 | if (regval == NULL) | |
532 | error ("Value of base register not available."); | |
1aa20aa8 | 533 | addr = value_as_address (regval); |
c5aa993b JM |
534 | addr += SYMBOL_VALUE (var); |
535 | break; | |
c906108c | 536 | } |
c5aa993b | 537 | |
c906108c SS |
538 | case LOC_TYPEDEF: |
539 | error ("Cannot look up value of a typedef"); | |
540 | break; | |
541 | ||
542 | case LOC_BLOCK: | |
543 | if (overlay_debugging) | |
c5aa993b | 544 | VALUE_ADDRESS (v) = symbol_overlayed_address |
c906108c SS |
545 | (BLOCK_START (SYMBOL_BLOCK_VALUE (var)), SYMBOL_BFD_SECTION (var)); |
546 | else | |
547 | VALUE_ADDRESS (v) = BLOCK_START (SYMBOL_BLOCK_VALUE (var)); | |
548 | return v; | |
549 | ||
550 | case LOC_REGISTER: | |
551 | case LOC_REGPARM: | |
552 | case LOC_REGPARM_ADDR: | |
553 | { | |
554 | struct block *b; | |
555 | int regno = SYMBOL_VALUE (var); | |
3d6d86c6 | 556 | struct value *regval; |
c906108c SS |
557 | |
558 | if (frame == NULL) | |
559 | return 0; | |
560 | b = get_frame_block (frame); | |
561 | ||
562 | if (SYMBOL_CLASS (var) == LOC_REGPARM_ADDR) | |
563 | { | |
564 | regval = value_from_register (lookup_pointer_type (type), | |
c5aa993b | 565 | regno, |
c906108c SS |
566 | frame); |
567 | ||
568 | if (regval == NULL) | |
569 | error ("Value of register variable not available."); | |
570 | ||
1aa20aa8 | 571 | addr = value_as_address (regval); |
c906108c SS |
572 | VALUE_LVAL (v) = lval_memory; |
573 | } | |
574 | else | |
575 | { | |
576 | regval = value_from_register (type, regno, frame); | |
577 | ||
578 | if (regval == NULL) | |
579 | error ("Value of register variable not available."); | |
580 | return regval; | |
581 | } | |
582 | } | |
583 | break; | |
584 | ||
585 | case LOC_UNRESOLVED: | |
586 | { | |
587 | struct minimal_symbol *msym; | |
588 | ||
589 | msym = lookup_minimal_symbol (SYMBOL_NAME (var), NULL, NULL); | |
590 | if (msym == NULL) | |
591 | return 0; | |
592 | if (overlay_debugging) | |
593 | addr = symbol_overlayed_address (SYMBOL_VALUE_ADDRESS (msym), | |
594 | SYMBOL_BFD_SECTION (msym)); | |
595 | else | |
596 | addr = SYMBOL_VALUE_ADDRESS (msym); | |
597 | } | |
598 | break; | |
599 | ||
600 | case LOC_OPTIMIZED_OUT: | |
601 | VALUE_LVAL (v) = not_lval; | |
602 | VALUE_OPTIMIZED_OUT (v) = 1; | |
603 | return v; | |
604 | ||
605 | default: | |
606 | error ("Cannot look up value of a botched symbol."); | |
607 | break; | |
608 | } | |
609 | ||
610 | VALUE_ADDRESS (v) = addr; | |
611 | VALUE_LAZY (v) = 1; | |
612 | return v; | |
613 | } | |
614 | ||
615 | /* Return a value of type TYPE, stored in register REGNUM, in frame | |
0f2c5ba5 | 616 | FRAME. |
c906108c SS |
617 | |
618 | NOTE: returns NULL if register value is not available. | |
619 | Caller will check return value or die! */ | |
620 | ||
3d6d86c6 | 621 | struct value * |
fba45db2 | 622 | value_from_register (struct type *type, int regnum, struct frame_info *frame) |
c906108c | 623 | { |
e6cbd02a | 624 | char *raw_buffer = (char*) alloca (MAX_REGISTER_RAW_SIZE); |
c906108c SS |
625 | CORE_ADDR addr; |
626 | int optim; | |
3d6d86c6 | 627 | struct value *v = allocate_value (type); |
c906108c SS |
628 | char *value_bytes = 0; |
629 | int value_bytes_copied = 0; | |
630 | int num_storage_locs; | |
631 | enum lval_type lval; | |
632 | int len; | |
633 | ||
634 | CHECK_TYPEDEF (type); | |
635 | len = TYPE_LENGTH (type); | |
636 | ||
637 | VALUE_REGNO (v) = regnum; | |
638 | ||
639 | num_storage_locs = (len > REGISTER_VIRTUAL_SIZE (regnum) ? | |
640 | ((len - 1) / REGISTER_RAW_SIZE (regnum)) + 1 : | |
641 | 1); | |
642 | ||
643 | if (num_storage_locs > 1 | |
644 | #ifdef GDB_TARGET_IS_H8500 | |
645 | || TYPE_CODE (type) == TYPE_CODE_PTR | |
646 | #endif | |
c5aa993b | 647 | ) |
c906108c SS |
648 | { |
649 | /* Value spread across multiple storage locations. */ | |
c5aa993b | 650 | |
c906108c SS |
651 | int local_regnum; |
652 | int mem_stor = 0, reg_stor = 0; | |
653 | int mem_tracking = 1; | |
654 | CORE_ADDR last_addr = 0; | |
655 | CORE_ADDR first_addr = 0; | |
656 | ||
657 | value_bytes = (char *) alloca (len + MAX_REGISTER_RAW_SIZE); | |
658 | ||
659 | /* Copy all of the data out, whereever it may be. */ | |
660 | ||
661 | #ifdef GDB_TARGET_IS_H8500 | |
662 | /* This piece of hideosity is required because the H8500 treats registers | |
663 | differently depending upon whether they are used as pointers or not. As a | |
664 | pointer, a register needs to have a page register tacked onto the front. | |
665 | An alternate way to do this would be to have gcc output different register | |
666 | numbers for the pointer & non-pointer form of the register. But, it | |
667 | doesn't, so we're stuck with this. */ | |
668 | ||
669 | if (TYPE_CODE (type) == TYPE_CODE_PTR | |
670 | && len > 2) | |
671 | { | |
672 | int page_regnum; | |
673 | ||
674 | switch (regnum) | |
675 | { | |
c5aa993b JM |
676 | case R0_REGNUM: |
677 | case R1_REGNUM: | |
678 | case R2_REGNUM: | |
679 | case R3_REGNUM: | |
c906108c SS |
680 | page_regnum = SEG_D_REGNUM; |
681 | break; | |
c5aa993b JM |
682 | case R4_REGNUM: |
683 | case R5_REGNUM: | |
c906108c SS |
684 | page_regnum = SEG_E_REGNUM; |
685 | break; | |
c5aa993b JM |
686 | case R6_REGNUM: |
687 | case R7_REGNUM: | |
c906108c SS |
688 | page_regnum = SEG_T_REGNUM; |
689 | break; | |
690 | } | |
691 | ||
692 | value_bytes[0] = 0; | |
693 | get_saved_register (value_bytes + 1, | |
694 | &optim, | |
695 | &addr, | |
696 | frame, | |
697 | page_regnum, | |
698 | &lval); | |
699 | ||
32178cab | 700 | if (register_cached (page_regnum) == -1) |
c906108c SS |
701 | return NULL; /* register value not available */ |
702 | ||
703 | if (lval == lval_register) | |
704 | reg_stor++; | |
705 | else | |
706 | mem_stor++; | |
707 | first_addr = addr; | |
708 | last_addr = addr; | |
709 | ||
710 | get_saved_register (value_bytes + 2, | |
711 | &optim, | |
712 | &addr, | |
713 | frame, | |
714 | regnum, | |
715 | &lval); | |
716 | ||
32178cab | 717 | if (register_cached (regnum) == -1) |
c906108c SS |
718 | return NULL; /* register value not available */ |
719 | ||
720 | if (lval == lval_register) | |
721 | reg_stor++; | |
722 | else | |
723 | { | |
724 | mem_stor++; | |
725 | mem_tracking = mem_tracking && (addr == last_addr); | |
726 | } | |
727 | last_addr = addr; | |
728 | } | |
729 | else | |
c5aa993b | 730 | #endif /* GDB_TARGET_IS_H8500 */ |
c906108c SS |
731 | for (local_regnum = regnum; |
732 | value_bytes_copied < len; | |
733 | (value_bytes_copied += REGISTER_RAW_SIZE (local_regnum), | |
734 | ++local_regnum)) | |
735 | { | |
736 | get_saved_register (value_bytes + value_bytes_copied, | |
737 | &optim, | |
738 | &addr, | |
739 | frame, | |
740 | local_regnum, | |
741 | &lval); | |
742 | ||
32178cab | 743 | if (register_cached (local_regnum) == -1) |
c5aa993b | 744 | return NULL; /* register value not available */ |
c906108c SS |
745 | |
746 | if (regnum == local_regnum) | |
747 | first_addr = addr; | |
748 | if (lval == lval_register) | |
749 | reg_stor++; | |
750 | else | |
751 | { | |
752 | mem_stor++; | |
c5aa993b | 753 | |
c906108c SS |
754 | mem_tracking = |
755 | (mem_tracking | |
756 | && (regnum == local_regnum | |
757 | || addr == last_addr)); | |
758 | } | |
759 | last_addr = addr; | |
760 | } | |
761 | ||
762 | if ((reg_stor && mem_stor) | |
763 | || (mem_stor && !mem_tracking)) | |
764 | /* Mixed storage; all of the hassle we just went through was | |
765 | for some good purpose. */ | |
766 | { | |
767 | VALUE_LVAL (v) = lval_reg_frame_relative; | |
768 | VALUE_FRAME (v) = FRAME_FP (frame); | |
769 | VALUE_FRAME_REGNUM (v) = regnum; | |
770 | } | |
771 | else if (mem_stor) | |
772 | { | |
773 | VALUE_LVAL (v) = lval_memory; | |
774 | VALUE_ADDRESS (v) = first_addr; | |
775 | } | |
776 | else if (reg_stor) | |
777 | { | |
778 | VALUE_LVAL (v) = lval_register; | |
779 | VALUE_ADDRESS (v) = first_addr; | |
780 | } | |
781 | else | |
8e65ff28 AC |
782 | internal_error (__FILE__, __LINE__, |
783 | "value_from_register: Value not stored anywhere!"); | |
c906108c SS |
784 | |
785 | VALUE_OPTIMIZED_OUT (v) = optim; | |
786 | ||
787 | /* Any structure stored in more than one register will always be | |
c5aa993b JM |
788 | an integral number of registers. Otherwise, you'd need to do |
789 | some fiddling with the last register copied here for little | |
790 | endian machines. */ | |
c906108c SS |
791 | |
792 | /* Copy into the contents section of the value. */ | |
793 | memcpy (VALUE_CONTENTS_RAW (v), value_bytes, len); | |
794 | ||
795 | /* Finally do any conversion necessary when extracting this | |
796 | type from more than one register. */ | |
797 | #ifdef REGISTER_CONVERT_TO_TYPE | |
c5aa993b | 798 | REGISTER_CONVERT_TO_TYPE (regnum, type, VALUE_CONTENTS_RAW (v)); |
c906108c SS |
799 | #endif |
800 | return v; | |
801 | } | |
802 | ||
803 | /* Data is completely contained within a single register. Locate the | |
804 | register's contents in a real register or in core; | |
805 | read the data in raw format. */ | |
806 | ||
807 | get_saved_register (raw_buffer, &optim, &addr, frame, regnum, &lval); | |
808 | ||
32178cab | 809 | if (register_cached (regnum) == -1) |
c5aa993b | 810 | return NULL; /* register value not available */ |
c906108c SS |
811 | |
812 | VALUE_OPTIMIZED_OUT (v) = optim; | |
813 | VALUE_LVAL (v) = lval; | |
814 | VALUE_ADDRESS (v) = addr; | |
815 | ||
816 | /* Convert raw data to virtual format if necessary. */ | |
c5aa993b | 817 | |
c906108c SS |
818 | if (REGISTER_CONVERTIBLE (regnum)) |
819 | { | |
820 | REGISTER_CONVERT_TO_VIRTUAL (regnum, type, | |
821 | raw_buffer, VALUE_CONTENTS_RAW (v)); | |
822 | } | |
823 | else | |
c906108c SS |
824 | { |
825 | /* Raw and virtual formats are the same for this register. */ | |
826 | ||
d7449b42 | 827 | if (TARGET_BYTE_ORDER == BFD_ENDIAN_BIG && len < REGISTER_RAW_SIZE (regnum)) |
c906108c | 828 | { |
c5aa993b | 829 | /* Big-endian, and we want less than full size. */ |
c906108c SS |
830 | VALUE_OFFSET (v) = REGISTER_RAW_SIZE (regnum) - len; |
831 | } | |
832 | ||
833 | memcpy (VALUE_CONTENTS_RAW (v), raw_buffer + VALUE_OFFSET (v), len); | |
834 | } | |
c5aa993b | 835 | |
c906108c SS |
836 | return v; |
837 | } | |
838 | \f | |
839 | /* Given a struct symbol for a variable or function, | |
840 | and a stack frame id, | |
841 | return a (pointer to a) struct value containing the properly typed | |
842 | address. */ | |
843 | ||
3d6d86c6 | 844 | struct value * |
fba45db2 | 845 | locate_var_value (register struct symbol *var, struct frame_info *frame) |
c906108c SS |
846 | { |
847 | CORE_ADDR addr = 0; | |
848 | struct type *type = SYMBOL_TYPE (var); | |
3d6d86c6 | 849 | struct value *lazy_value; |
c906108c SS |
850 | |
851 | /* Evaluate it first; if the result is a memory address, we're fine. | |
852 | Lazy evaluation pays off here. */ | |
853 | ||
854 | lazy_value = read_var_value (var, frame); | |
855 | if (lazy_value == 0) | |
856 | error ("Address of \"%s\" is unknown.", SYMBOL_SOURCE_NAME (var)); | |
857 | ||
858 | if (VALUE_LAZY (lazy_value) | |
859 | || TYPE_CODE (type) == TYPE_CODE_FUNC) | |
860 | { | |
3d6d86c6 | 861 | struct value *val; |
c906108c SS |
862 | |
863 | addr = VALUE_ADDRESS (lazy_value); | |
4478b372 | 864 | val = value_from_pointer (lookup_pointer_type (type), addr); |
c906108c SS |
865 | VALUE_BFD_SECTION (val) = VALUE_BFD_SECTION (lazy_value); |
866 | return val; | |
867 | } | |
868 | ||
869 | /* Not a memory address; check what the problem was. */ | |
c5aa993b | 870 | switch (VALUE_LVAL (lazy_value)) |
c906108c SS |
871 | { |
872 | case lval_register: | |
14e534aa PM |
873 | gdb_assert (REGISTER_NAME (VALUE_REGNO (lazy_value)) != NULL |
874 | && *REGISTER_NAME (VALUE_REGNO (lazy_value)) != '\0'); | |
875 | error("Address requested for identifier " | |
876 | "\"%s\" which is in register $%s", | |
877 | SYMBOL_SOURCE_NAME (var), | |
878 | REGISTER_NAME (VALUE_REGNO (lazy_value))); | |
879 | break; | |
880 | ||
c906108c | 881 | case lval_reg_frame_relative: |
14e534aa PM |
882 | gdb_assert (REGISTER_NAME (VALUE_FRAME_REGNUM (lazy_value)) != NULL |
883 | && *REGISTER_NAME (VALUE_FRAME_REGNUM (lazy_value)) != '\0'); | |
884 | error("Address requested for identifier " | |
885 | "\"%s\" which is in frame register $%s", | |
886 | SYMBOL_SOURCE_NAME (var), | |
887 | REGISTER_NAME (VALUE_FRAME_REGNUM (lazy_value))); | |
c906108c SS |
888 | break; |
889 | ||
890 | default: | |
891 | error ("Can't take address of \"%s\" which isn't an lvalue.", | |
892 | SYMBOL_SOURCE_NAME (var)); | |
893 | break; | |
894 | } | |
c5aa993b | 895 | return 0; /* For lint -- never reached */ |
c906108c | 896 | } |