Fix bug in sh_elf_reloc_loop
[deliverable/binutils-gdb.git] / gdb / findvar.c
1 /* Find a variable's value in memory, for GDB, the GNU debugger.
2 Copyright 1986, 87, 89, 91, 94, 95, 96, 1998
3 Free Software Foundation, Inc.
4
5 This file is part of GDB.
6
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
9 the Free Software Foundation; either version 2 of the License, or
10 (at your option) any later version.
11
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.
16
17 You should have received a copy of the GNU General Public License
18 along with this program; if not, write to the Free Software
19 Foundation, Inc., 59 Temple Place - Suite 330,
20 Boston, MA 02111-1307, USA. */
21
22 #include "defs.h"
23 #include "symtab.h"
24 #include "gdbtypes.h"
25 #include "frame.h"
26 #include "value.h"
27 #include "gdbcore.h"
28 #include "inferior.h"
29 #include "target.h"
30 #include "gdb_string.h"
31 #include "floatformat.h"
32 #include "symfile.h" /* for overlay functions */
33
34 /* This is used to indicate that we don't know the format of the floating point
35 number. Typically, this is useful for native ports, where the actual format
36 is irrelevant, since no conversions will be taking place. */
37
38 const struct floatformat floatformat_unknown;
39
40 /* Basic byte-swapping routines. GDB has needed these for a long time...
41 All extract a target-format integer at ADDR which is LEN bytes long. */
42
43 #if TARGET_CHAR_BIT != 8 || HOST_CHAR_BIT != 8
44 /* 8 bit characters are a pretty safe assumption these days, so we
45 assume it throughout all these swapping routines. If we had to deal with
46 9 bit characters, we would need to make len be in bits and would have
47 to re-write these routines... */
48 you lose
49 #endif
50
51 LONGEST
52 extract_signed_integer (void *addr, int len)
53 {
54 LONGEST retval;
55 unsigned char *p;
56 unsigned char *startaddr = (unsigned char *) addr;
57 unsigned char *endaddr = startaddr + len;
58
59 if (len > (int) sizeof (LONGEST))
60 error ("\
61 That operation is not available on integers of more than %d bytes.",
62 sizeof (LONGEST));
63
64 /* Start at the most significant end of the integer, and work towards
65 the least significant. */
66 if (TARGET_BYTE_ORDER == BIG_ENDIAN)
67 {
68 p = startaddr;
69 /* Do the sign extension once at the start. */
70 retval = ((LONGEST) * p ^ 0x80) - 0x80;
71 for (++p; p < endaddr; ++p)
72 retval = (retval << 8) | *p;
73 }
74 else
75 {
76 p = endaddr - 1;
77 /* Do the sign extension once at the start. */
78 retval = ((LONGEST) * p ^ 0x80) - 0x80;
79 for (--p; p >= startaddr; --p)
80 retval = (retval << 8) | *p;
81 }
82 return retval;
83 }
84
85 ULONGEST
86 extract_unsigned_integer (void *addr, int len)
87 {
88 ULONGEST retval;
89 unsigned char *p;
90 unsigned char *startaddr = (unsigned char *) addr;
91 unsigned char *endaddr = startaddr + len;
92
93 if (len > (int) sizeof (ULONGEST))
94 error ("\
95 That operation is not available on integers of more than %d bytes.",
96 sizeof (ULONGEST));
97
98 /* Start at the most significant end of the integer, and work towards
99 the least significant. */
100 retval = 0;
101 if (TARGET_BYTE_ORDER == BIG_ENDIAN)
102 {
103 for (p = startaddr; p < endaddr; ++p)
104 retval = (retval << 8) | *p;
105 }
106 else
107 {
108 for (p = endaddr - 1; p >= startaddr; --p)
109 retval = (retval << 8) | *p;
110 }
111 return retval;
112 }
113
114 /* Sometimes a long long unsigned integer can be extracted as a
115 LONGEST value. This is done so that we can print these values
116 better. If this integer can be converted to a LONGEST, this
117 function returns 1 and sets *PVAL. Otherwise it returns 0. */
118
119 int
120 extract_long_unsigned_integer (void *addr, int orig_len, LONGEST *pval)
121 {
122 char *p, *first_addr;
123 int len;
124
125 len = orig_len;
126 if (TARGET_BYTE_ORDER == BIG_ENDIAN)
127 {
128 for (p = (char *) addr;
129 len > (int) sizeof (LONGEST) && p < (char *) addr + orig_len;
130 p++)
131 {
132 if (*p == 0)
133 len--;
134 else
135 break;
136 }
137 first_addr = p;
138 }
139 else
140 {
141 first_addr = (char *) addr;
142 for (p = (char *) addr + orig_len - 1;
143 len > (int) sizeof (LONGEST) && p >= (char *) addr;
144 p--)
145 {
146 if (*p == 0)
147 len--;
148 else
149 break;
150 }
151 }
152
153 if (len <= (int) sizeof (LONGEST))
154 {
155 *pval = (LONGEST) extract_unsigned_integer (first_addr,
156 sizeof (LONGEST));
157 return 1;
158 }
159
160 return 0;
161 }
162
163
164 /* Treat the LEN bytes at ADDR as a target-format address, and return
165 that address. ADDR is a buffer in the GDB process, not in the
166 inferior.
167
168 This function should only be used by target-specific code. It
169 assumes that a pointer has the same representation as that thing's
170 address represented as an integer. Some machines use word
171 addresses, or similarly munged things, for certain types of
172 pointers, so that assumption doesn't hold everywhere.
173
174 Common code should use extract_typed_address instead, or something
175 else based on POINTER_TO_ADDRESS. */
176
177 CORE_ADDR
178 extract_address (void *addr, int len)
179 {
180 /* Assume a CORE_ADDR can fit in a LONGEST (for now). Not sure
181 whether we want this to be true eventually. */
182 return (CORE_ADDR) extract_unsigned_integer (addr, len);
183 }
184
185
186 /* Treat the bytes at BUF as a pointer of type TYPE, and return the
187 address it represents. */
188 CORE_ADDR
189 extract_typed_address (void *buf, struct type *type)
190 {
191 if (TYPE_CODE (type) != TYPE_CODE_PTR
192 && TYPE_CODE (type) != TYPE_CODE_REF)
193 internal_error ("findvar.c (extract_typed_address): "
194 "type is not a pointer or reference");
195
196 return POINTER_TO_ADDRESS (type, buf);
197 }
198
199
200 void
201 store_signed_integer (void *addr, int len, LONGEST val)
202 {
203 unsigned char *p;
204 unsigned char *startaddr = (unsigned char *) addr;
205 unsigned char *endaddr = startaddr + len;
206
207 /* Start at the least significant end of the integer, and work towards
208 the most significant. */
209 if (TARGET_BYTE_ORDER == BIG_ENDIAN)
210 {
211 for (p = endaddr - 1; p >= startaddr; --p)
212 {
213 *p = val & 0xff;
214 val >>= 8;
215 }
216 }
217 else
218 {
219 for (p = startaddr; p < endaddr; ++p)
220 {
221 *p = val & 0xff;
222 val >>= 8;
223 }
224 }
225 }
226
227 void
228 store_unsigned_integer (void *addr, int len, ULONGEST val)
229 {
230 unsigned char *p;
231 unsigned char *startaddr = (unsigned char *) addr;
232 unsigned char *endaddr = startaddr + len;
233
234 /* Start at the least significant end of the integer, and work towards
235 the most significant. */
236 if (TARGET_BYTE_ORDER == BIG_ENDIAN)
237 {
238 for (p = endaddr - 1; p >= startaddr; --p)
239 {
240 *p = val & 0xff;
241 val >>= 8;
242 }
243 }
244 else
245 {
246 for (p = startaddr; p < endaddr; ++p)
247 {
248 *p = val & 0xff;
249 val >>= 8;
250 }
251 }
252 }
253
254 /* Store the address VAL as a LEN-byte value in target byte order at
255 ADDR. ADDR is a buffer in the GDB process, not in the inferior.
256
257 This function should only be used by target-specific code. It
258 assumes that a pointer has the same representation as that thing's
259 address represented as an integer. Some machines use word
260 addresses, or similarly munged things, for certain types of
261 pointers, so that assumption doesn't hold everywhere.
262
263 Common code should use store_typed_address instead, or something else
264 based on ADDRESS_TO_POINTER. */
265 void
266 store_address (void *addr, int len, LONGEST val)
267 {
268 store_unsigned_integer (addr, len, val);
269 }
270
271
272 /* Store the address ADDR as a pointer of type TYPE at BUF, in target
273 form. */
274 void
275 store_typed_address (void *buf, struct type *type, CORE_ADDR addr)
276 {
277 if (TYPE_CODE (type) != TYPE_CODE_PTR
278 && TYPE_CODE (type) != TYPE_CODE_REF)
279 internal_error ("findvar.c (store_typed_address): "
280 "type is not a pointer or reference");
281
282 ADDRESS_TO_POINTER (type, buf, addr);
283 }
284
285
286
287 \f
288 /* Extract a floating-point number from a target-order byte-stream at ADDR.
289 Returns the value as type DOUBLEST.
290
291 If the host and target formats agree, we just copy the raw data into the
292 appropriate type of variable and return, letting the host increase precision
293 as necessary. Otherwise, we call the conversion routine and let it do the
294 dirty work. */
295
296 DOUBLEST
297 extract_floating (void *addr, int len)
298 {
299 DOUBLEST dretval;
300
301 if (len * TARGET_CHAR_BIT == TARGET_FLOAT_BIT)
302 {
303 if (HOST_FLOAT_FORMAT == TARGET_FLOAT_FORMAT)
304 {
305 float retval;
306
307 memcpy (&retval, addr, sizeof (retval));
308 return retval;
309 }
310 else
311 floatformat_to_doublest (TARGET_FLOAT_FORMAT, addr, &dretval);
312 }
313 else if (len * TARGET_CHAR_BIT == TARGET_DOUBLE_BIT)
314 {
315 if (HOST_DOUBLE_FORMAT == TARGET_DOUBLE_FORMAT)
316 {
317 double retval;
318
319 memcpy (&retval, addr, sizeof (retval));
320 return retval;
321 }
322 else
323 floatformat_to_doublest (TARGET_DOUBLE_FORMAT, addr, &dretval);
324 }
325 else if (len * TARGET_CHAR_BIT == TARGET_LONG_DOUBLE_BIT)
326 {
327 if (HOST_LONG_DOUBLE_FORMAT == TARGET_LONG_DOUBLE_FORMAT)
328 {
329 DOUBLEST retval;
330
331 memcpy (&retval, addr, sizeof (retval));
332 return retval;
333 }
334 else
335 floatformat_to_doublest (TARGET_LONG_DOUBLE_FORMAT, addr, &dretval);
336 }
337 else
338 {
339 error ("Can't deal with a floating point number of %d bytes.", len);
340 }
341
342 return dretval;
343 }
344
345 void
346 store_floating (void *addr, int len, DOUBLEST val)
347 {
348 if (len * TARGET_CHAR_BIT == TARGET_FLOAT_BIT)
349 {
350 if (HOST_FLOAT_FORMAT == TARGET_FLOAT_FORMAT)
351 {
352 float floatval = val;
353
354 memcpy (addr, &floatval, sizeof (floatval));
355 }
356 else
357 floatformat_from_doublest (TARGET_FLOAT_FORMAT, &val, addr);
358 }
359 else if (len * TARGET_CHAR_BIT == TARGET_DOUBLE_BIT)
360 {
361 if (HOST_DOUBLE_FORMAT == TARGET_DOUBLE_FORMAT)
362 {
363 double doubleval = val;
364
365 memcpy (addr, &doubleval, sizeof (doubleval));
366 }
367 else
368 floatformat_from_doublest (TARGET_DOUBLE_FORMAT, &val, addr);
369 }
370 else if (len * TARGET_CHAR_BIT == TARGET_LONG_DOUBLE_BIT)
371 {
372 if (HOST_LONG_DOUBLE_FORMAT == TARGET_LONG_DOUBLE_FORMAT)
373 memcpy (addr, &val, sizeof (val));
374 else
375 floatformat_from_doublest (TARGET_LONG_DOUBLE_FORMAT, &val, addr);
376 }
377 else
378 {
379 error ("Can't deal with a floating point number of %d bytes.", len);
380 }
381 }
382
383 /* Return a `value' with the contents of register REGNUM
384 in its virtual format, with the type specified by
385 REGISTER_VIRTUAL_TYPE.
386
387 NOTE: returns NULL if register value is not available.
388 Caller will check return value or die! */
389
390 value_ptr
391 value_of_register (int regnum)
392 {
393 CORE_ADDR addr;
394 int optim;
395 register value_ptr reg_val;
396 char raw_buffer[MAX_REGISTER_RAW_SIZE];
397 enum lval_type lval;
398
399 get_saved_register (raw_buffer, &optim, &addr,
400 selected_frame, regnum, &lval);
401
402 if (register_cached (regnum) < 0)
403 return NULL; /* register value not available */
404
405 reg_val = allocate_value (REGISTER_VIRTUAL_TYPE (regnum));
406
407 /* Convert raw data to virtual format if necessary. */
408
409 if (REGISTER_CONVERTIBLE (regnum))
410 {
411 REGISTER_CONVERT_TO_VIRTUAL (regnum, REGISTER_VIRTUAL_TYPE (regnum),
412 raw_buffer, VALUE_CONTENTS_RAW (reg_val));
413 }
414 else if (REGISTER_RAW_SIZE (regnum) == REGISTER_VIRTUAL_SIZE (regnum))
415 memcpy (VALUE_CONTENTS_RAW (reg_val), raw_buffer,
416 REGISTER_RAW_SIZE (regnum));
417 else
418 internal_error ("Register \"%s\" (%d) has conflicting raw (%d) and virtual (%d) size",
419 REGISTER_NAME (regnum),
420 regnum,
421 REGISTER_RAW_SIZE (regnum),
422 REGISTER_VIRTUAL_SIZE (regnum));
423 VALUE_LVAL (reg_val) = lval;
424 VALUE_ADDRESS (reg_val) = addr;
425 VALUE_REGNO (reg_val) = regnum;
426 VALUE_OPTIMIZED_OUT (reg_val) = optim;
427 return reg_val;
428 }
429
430 /* Given a pointer of type TYPE in target form in BUF, return the
431 address it represents. */
432 CORE_ADDR
433 unsigned_pointer_to_address (struct type *type, void *buf)
434 {
435 return extract_address (buf, TYPE_LENGTH (type));
436 }
437
438 CORE_ADDR
439 signed_pointer_to_address (struct type *type, void *buf)
440 {
441 return extract_signed_integer (buf, TYPE_LENGTH (type));
442 }
443
444 /* Given an address, store it as a pointer of type TYPE in target
445 format in BUF. */
446 void
447 unsigned_address_to_pointer (struct type *type, void *buf, CORE_ADDR addr)
448 {
449 store_address (buf, TYPE_LENGTH (type), addr);
450 }
451
452 void
453 address_to_signed_pointer (struct type *type, void *buf, CORE_ADDR addr)
454 {
455 store_signed_integer (buf, TYPE_LENGTH (type), addr);
456 }
457 \f
458 /* Will calling read_var_value or locate_var_value on SYM end
459 up caring what frame it is being evaluated relative to? SYM must
460 be non-NULL. */
461 int
462 symbol_read_needs_frame (struct symbol *sym)
463 {
464 switch (SYMBOL_CLASS (sym))
465 {
466 /* All cases listed explicitly so that gcc -Wall will detect it if
467 we failed to consider one. */
468 case LOC_REGISTER:
469 case LOC_ARG:
470 case LOC_REF_ARG:
471 case LOC_REGPARM:
472 case LOC_REGPARM_ADDR:
473 case LOC_LOCAL:
474 case LOC_LOCAL_ARG:
475 case LOC_BASEREG:
476 case LOC_BASEREG_ARG:
477 case LOC_THREAD_LOCAL_STATIC:
478 return 1;
479
480 case LOC_UNDEF:
481 case LOC_CONST:
482 case LOC_STATIC:
483 case LOC_INDIRECT:
484 case LOC_TYPEDEF:
485
486 case LOC_LABEL:
487 /* Getting the address of a label can be done independently of the block,
488 even if some *uses* of that address wouldn't work so well without
489 the right frame. */
490
491 case LOC_BLOCK:
492 case LOC_CONST_BYTES:
493 case LOC_UNRESOLVED:
494 case LOC_OPTIMIZED_OUT:
495 return 0;
496 }
497 return 1;
498 }
499
500 /* Given a struct symbol for a variable,
501 and a stack frame id, read the value of the variable
502 and return a (pointer to a) struct value containing the value.
503 If the variable cannot be found, return a zero pointer.
504 If FRAME is NULL, use the selected_frame. */
505
506 value_ptr
507 read_var_value (register struct symbol *var, struct frame_info *frame)
508 {
509 register value_ptr v;
510 struct type *type = SYMBOL_TYPE (var);
511 CORE_ADDR addr;
512 register int len;
513
514 v = allocate_value (type);
515 VALUE_LVAL (v) = lval_memory; /* The most likely possibility. */
516 VALUE_BFD_SECTION (v) = SYMBOL_BFD_SECTION (var);
517
518 len = TYPE_LENGTH (type);
519
520 if (frame == NULL)
521 frame = selected_frame;
522
523 switch (SYMBOL_CLASS (var))
524 {
525 case LOC_CONST:
526 /* Put the constant back in target format. */
527 store_signed_integer (VALUE_CONTENTS_RAW (v), len,
528 (LONGEST) SYMBOL_VALUE (var));
529 VALUE_LVAL (v) = not_lval;
530 return v;
531
532 case LOC_LABEL:
533 /* Put the constant back in target format. */
534 if (overlay_debugging)
535 {
536 CORE_ADDR addr
537 = symbol_overlayed_address (SYMBOL_VALUE_ADDRESS (var),
538 SYMBOL_BFD_SECTION (var));
539 store_typed_address (VALUE_CONTENTS_RAW (v), type, addr);
540 }
541 else
542 store_typed_address (VALUE_CONTENTS_RAW (v), type,
543 SYMBOL_VALUE_ADDRESS (var));
544 VALUE_LVAL (v) = not_lval;
545 return v;
546
547 case LOC_CONST_BYTES:
548 {
549 char *bytes_addr;
550 bytes_addr = SYMBOL_VALUE_BYTES (var);
551 memcpy (VALUE_CONTENTS_RAW (v), bytes_addr, len);
552 VALUE_LVAL (v) = not_lval;
553 return v;
554 }
555
556 case LOC_STATIC:
557 if (overlay_debugging)
558 addr = symbol_overlayed_address (SYMBOL_VALUE_ADDRESS (var),
559 SYMBOL_BFD_SECTION (var));
560 else
561 addr = SYMBOL_VALUE_ADDRESS (var);
562 break;
563
564 case LOC_INDIRECT:
565 /* The import slot does not have a real address in it from the
566 dynamic loader (dld.sl on HP-UX), if the target hasn't begun
567 execution yet, so check for that. */
568 if (!target_has_execution)
569 error ("\
570 Attempt to access variable defined in different shared object or load module when\n\
571 addresses have not been bound by the dynamic loader. Try again when executable is running.");
572
573 addr = SYMBOL_VALUE_ADDRESS (var);
574 addr = read_memory_unsigned_integer
575 (addr, TARGET_PTR_BIT / TARGET_CHAR_BIT);
576 break;
577
578 case LOC_ARG:
579 if (frame == NULL)
580 return 0;
581 addr = FRAME_ARGS_ADDRESS (frame);
582 if (!addr)
583 return 0;
584 addr += SYMBOL_VALUE (var);
585 break;
586
587 case LOC_REF_ARG:
588 if (frame == NULL)
589 return 0;
590 addr = FRAME_ARGS_ADDRESS (frame);
591 if (!addr)
592 return 0;
593 addr += SYMBOL_VALUE (var);
594 addr = read_memory_unsigned_integer
595 (addr, TARGET_PTR_BIT / TARGET_CHAR_BIT);
596 break;
597
598 case LOC_LOCAL:
599 case LOC_LOCAL_ARG:
600 if (frame == NULL)
601 return 0;
602 addr = FRAME_LOCALS_ADDRESS (frame);
603 addr += SYMBOL_VALUE (var);
604 break;
605
606 case LOC_BASEREG:
607 case LOC_BASEREG_ARG:
608 {
609 char buf[MAX_REGISTER_RAW_SIZE];
610 get_saved_register (buf, NULL, NULL, frame, SYMBOL_BASEREG (var),
611 NULL);
612 addr = extract_address (buf, REGISTER_RAW_SIZE (SYMBOL_BASEREG (var)));
613 addr += SYMBOL_VALUE (var);
614 break;
615 }
616
617 case LOC_THREAD_LOCAL_STATIC:
618 {
619 char buf[MAX_REGISTER_RAW_SIZE];
620
621 get_saved_register (buf, NULL, NULL, frame, SYMBOL_BASEREG (var),
622 NULL);
623 addr = extract_address (buf, REGISTER_RAW_SIZE (SYMBOL_BASEREG (var)));
624 addr += SYMBOL_VALUE (var);
625 break;
626 }
627
628 case LOC_TYPEDEF:
629 error ("Cannot look up value of a typedef");
630 break;
631
632 case LOC_BLOCK:
633 if (overlay_debugging)
634 VALUE_ADDRESS (v) = symbol_overlayed_address
635 (BLOCK_START (SYMBOL_BLOCK_VALUE (var)), SYMBOL_BFD_SECTION (var));
636 else
637 VALUE_ADDRESS (v) = BLOCK_START (SYMBOL_BLOCK_VALUE (var));
638 return v;
639
640 case LOC_REGISTER:
641 case LOC_REGPARM:
642 case LOC_REGPARM_ADDR:
643 {
644 struct block *b;
645 int regno = SYMBOL_VALUE (var);
646 value_ptr regval;
647
648 if (frame == NULL)
649 return 0;
650 b = get_frame_block (frame);
651
652 if (SYMBOL_CLASS (var) == LOC_REGPARM_ADDR)
653 {
654 regval = value_from_register (lookup_pointer_type (type),
655 regno,
656 frame);
657
658 if (regval == NULL)
659 error ("Value of register variable not available.");
660
661 addr = value_as_pointer (regval);
662 VALUE_LVAL (v) = lval_memory;
663 }
664 else
665 {
666 regval = value_from_register (type, regno, frame);
667
668 if (regval == NULL)
669 error ("Value of register variable not available.");
670 return regval;
671 }
672 }
673 break;
674
675 case LOC_UNRESOLVED:
676 {
677 struct minimal_symbol *msym;
678
679 msym = lookup_minimal_symbol (SYMBOL_NAME (var), NULL, NULL);
680 if (msym == NULL)
681 return 0;
682 if (overlay_debugging)
683 addr = symbol_overlayed_address (SYMBOL_VALUE_ADDRESS (msym),
684 SYMBOL_BFD_SECTION (msym));
685 else
686 addr = SYMBOL_VALUE_ADDRESS (msym);
687 }
688 break;
689
690 case LOC_OPTIMIZED_OUT:
691 VALUE_LVAL (v) = not_lval;
692 VALUE_OPTIMIZED_OUT (v) = 1;
693 return v;
694
695 default:
696 error ("Cannot look up value of a botched symbol.");
697 break;
698 }
699
700 VALUE_ADDRESS (v) = addr;
701 VALUE_LAZY (v) = 1;
702 return v;
703 }
704
705 /* Return a value of type TYPE, stored in register REGNUM, in frame
706 FRAME.
707
708 NOTE: returns NULL if register value is not available.
709 Caller will check return value or die! */
710
711 value_ptr
712 value_from_register (struct type *type, int regnum, struct frame_info *frame)
713 {
714 char raw_buffer[MAX_REGISTER_RAW_SIZE];
715 CORE_ADDR addr;
716 int optim;
717 value_ptr v = allocate_value (type);
718 char *value_bytes = 0;
719 int value_bytes_copied = 0;
720 int num_storage_locs;
721 enum lval_type lval;
722 int len;
723
724 CHECK_TYPEDEF (type);
725 len = TYPE_LENGTH (type);
726
727 /* Pointers on D10V are really only 16 bits,
728 but we lie to gdb elsewhere... */
729 if (GDB_TARGET_IS_D10V && TYPE_CODE (type) == TYPE_CODE_PTR)
730 len = 2;
731
732 VALUE_REGNO (v) = regnum;
733
734 num_storage_locs = (len > REGISTER_VIRTUAL_SIZE (regnum) ?
735 ((len - 1) / REGISTER_RAW_SIZE (regnum)) + 1 :
736 1);
737
738 if (num_storage_locs > 1
739 #ifdef GDB_TARGET_IS_H8500
740 || TYPE_CODE (type) == TYPE_CODE_PTR
741 #endif
742 )
743 {
744 /* Value spread across multiple storage locations. */
745
746 int local_regnum;
747 int mem_stor = 0, reg_stor = 0;
748 int mem_tracking = 1;
749 CORE_ADDR last_addr = 0;
750 CORE_ADDR first_addr = 0;
751
752 value_bytes = (char *) alloca (len + MAX_REGISTER_RAW_SIZE);
753
754 /* Copy all of the data out, whereever it may be. */
755
756 #ifdef GDB_TARGET_IS_H8500
757 /* This piece of hideosity is required because the H8500 treats registers
758 differently depending upon whether they are used as pointers or not. As a
759 pointer, a register needs to have a page register tacked onto the front.
760 An alternate way to do this would be to have gcc output different register
761 numbers for the pointer & non-pointer form of the register. But, it
762 doesn't, so we're stuck with this. */
763
764 if (TYPE_CODE (type) == TYPE_CODE_PTR
765 && len > 2)
766 {
767 int page_regnum;
768
769 switch (regnum)
770 {
771 case R0_REGNUM:
772 case R1_REGNUM:
773 case R2_REGNUM:
774 case R3_REGNUM:
775 page_regnum = SEG_D_REGNUM;
776 break;
777 case R4_REGNUM:
778 case R5_REGNUM:
779 page_regnum = SEG_E_REGNUM;
780 break;
781 case R6_REGNUM:
782 case R7_REGNUM:
783 page_regnum = SEG_T_REGNUM;
784 break;
785 }
786
787 value_bytes[0] = 0;
788 get_saved_register (value_bytes + 1,
789 &optim,
790 &addr,
791 frame,
792 page_regnum,
793 &lval);
794
795 if (register_cached (page_regnum) == -1)
796 return NULL; /* register value not available */
797
798 if (lval == lval_register)
799 reg_stor++;
800 else
801 mem_stor++;
802 first_addr = addr;
803 last_addr = addr;
804
805 get_saved_register (value_bytes + 2,
806 &optim,
807 &addr,
808 frame,
809 regnum,
810 &lval);
811
812 if (register_cached (regnum) == -1)
813 return NULL; /* register value not available */
814
815 if (lval == lval_register)
816 reg_stor++;
817 else
818 {
819 mem_stor++;
820 mem_tracking = mem_tracking && (addr == last_addr);
821 }
822 last_addr = addr;
823 }
824 else
825 #endif /* GDB_TARGET_IS_H8500 */
826 for (local_regnum = regnum;
827 value_bytes_copied < len;
828 (value_bytes_copied += REGISTER_RAW_SIZE (local_regnum),
829 ++local_regnum))
830 {
831 get_saved_register (value_bytes + value_bytes_copied,
832 &optim,
833 &addr,
834 frame,
835 local_regnum,
836 &lval);
837
838 if (register_cached (local_regnum) == -1)
839 return NULL; /* register value not available */
840
841 if (regnum == local_regnum)
842 first_addr = addr;
843 if (lval == lval_register)
844 reg_stor++;
845 else
846 {
847 mem_stor++;
848
849 mem_tracking =
850 (mem_tracking
851 && (regnum == local_regnum
852 || addr == last_addr));
853 }
854 last_addr = addr;
855 }
856
857 if ((reg_stor && mem_stor)
858 || (mem_stor && !mem_tracking))
859 /* Mixed storage; all of the hassle we just went through was
860 for some good purpose. */
861 {
862 VALUE_LVAL (v) = lval_reg_frame_relative;
863 VALUE_FRAME (v) = FRAME_FP (frame);
864 VALUE_FRAME_REGNUM (v) = regnum;
865 }
866 else if (mem_stor)
867 {
868 VALUE_LVAL (v) = lval_memory;
869 VALUE_ADDRESS (v) = first_addr;
870 }
871 else if (reg_stor)
872 {
873 VALUE_LVAL (v) = lval_register;
874 VALUE_ADDRESS (v) = first_addr;
875 }
876 else
877 internal_error ("value_from_register: Value not stored anywhere!");
878
879 VALUE_OPTIMIZED_OUT (v) = optim;
880
881 /* Any structure stored in more than one register will always be
882 an integral number of registers. Otherwise, you'd need to do
883 some fiddling with the last register copied here for little
884 endian machines. */
885
886 /* Copy into the contents section of the value. */
887 memcpy (VALUE_CONTENTS_RAW (v), value_bytes, len);
888
889 /* Finally do any conversion necessary when extracting this
890 type from more than one register. */
891 #ifdef REGISTER_CONVERT_TO_TYPE
892 REGISTER_CONVERT_TO_TYPE (regnum, type, VALUE_CONTENTS_RAW (v));
893 #endif
894 return v;
895 }
896
897 /* Data is completely contained within a single register. Locate the
898 register's contents in a real register or in core;
899 read the data in raw format. */
900
901 get_saved_register (raw_buffer, &optim, &addr, frame, regnum, &lval);
902
903 if (register_cached (regnum) == -1)
904 return NULL; /* register value not available */
905
906 VALUE_OPTIMIZED_OUT (v) = optim;
907 VALUE_LVAL (v) = lval;
908 VALUE_ADDRESS (v) = addr;
909
910 /* Convert raw data to virtual format if necessary. */
911
912 if (REGISTER_CONVERTIBLE (regnum))
913 {
914 REGISTER_CONVERT_TO_VIRTUAL (regnum, type,
915 raw_buffer, VALUE_CONTENTS_RAW (v));
916 }
917 else
918 {
919 /* Raw and virtual formats are the same for this register. */
920
921 if (TARGET_BYTE_ORDER == BIG_ENDIAN && len < REGISTER_RAW_SIZE (regnum))
922 {
923 /* Big-endian, and we want less than full size. */
924 VALUE_OFFSET (v) = REGISTER_RAW_SIZE (regnum) - len;
925 }
926
927 memcpy (VALUE_CONTENTS_RAW (v), raw_buffer + VALUE_OFFSET (v), len);
928 }
929
930 if (GDB_TARGET_IS_D10V
931 && TYPE_CODE (type) == TYPE_CODE_PTR)
932 {
933 unsigned long num;
934 unsigned short snum;
935
936 snum = (unsigned short)
937 extract_unsigned_integer (VALUE_CONTENTS_RAW (v), 2);
938
939 if (TYPE_TARGET_TYPE (type) /* pointer to function */
940 && (TYPE_CODE (TYPE_TARGET_TYPE (type)) == TYPE_CODE_FUNC))
941 num = D10V_MAKE_IADDR (snum);
942 else /* pointer to data */
943 num = D10V_MAKE_DADDR (snum);
944
945 store_address (VALUE_CONTENTS_RAW (v), 4, num);
946 }
947
948 return v;
949 }
950 \f
951 /* Given a struct symbol for a variable or function,
952 and a stack frame id,
953 return a (pointer to a) struct value containing the properly typed
954 address. */
955
956 value_ptr
957 locate_var_value (register struct symbol *var, struct frame_info *frame)
958 {
959 CORE_ADDR addr = 0;
960 struct type *type = SYMBOL_TYPE (var);
961 value_ptr lazy_value;
962
963 /* Evaluate it first; if the result is a memory address, we're fine.
964 Lazy evaluation pays off here. */
965
966 lazy_value = read_var_value (var, frame);
967 if (lazy_value == 0)
968 error ("Address of \"%s\" is unknown.", SYMBOL_SOURCE_NAME (var));
969
970 if (VALUE_LAZY (lazy_value)
971 || TYPE_CODE (type) == TYPE_CODE_FUNC)
972 {
973 value_ptr val;
974
975 addr = VALUE_ADDRESS (lazy_value);
976 val = value_from_pointer (lookup_pointer_type (type), addr);
977 VALUE_BFD_SECTION (val) = VALUE_BFD_SECTION (lazy_value);
978 return val;
979 }
980
981 /* Not a memory address; check what the problem was. */
982 switch (VALUE_LVAL (lazy_value))
983 {
984 case lval_register:
985 case lval_reg_frame_relative:
986 error ("Address requested for identifier \"%s\" which is in a register.",
987 SYMBOL_SOURCE_NAME (var));
988 break;
989
990 default:
991 error ("Can't take address of \"%s\" which isn't an lvalue.",
992 SYMBOL_SOURCE_NAME (var));
993 break;
994 }
995 return 0; /* For lint -- never reached */
996 }
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