1 /* DWARF 2 location expression support for GDB.
3 Copyright (C) 2003-2016 Free Software Foundation, Inc.
5 Contributed by Daniel Jacobowitz, MontaVista Software, Inc.
7 This file is part of GDB.
9 This program is free software; you can redistribute it and/or modify
10 it under the terms of the GNU General Public License as published by
11 the Free Software Foundation; either version 3 of the License, or
12 (at your option) any later version.
14 This program is distributed in the hope that it will be useful,
15 but WITHOUT ANY WARRANTY; without even the implied warranty of
16 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
17 GNU General Public License for more details.
19 You should have received a copy of the GNU General Public License
20 along with this program. If not, see <http://www.gnu.org/licenses/>. */
35 #include "complaints.h"
37 #include "dwarf2expr.h"
38 #include "dwarf2loc.h"
39 #include "dwarf2-frame.h"
40 #include "compile/compile.h"
42 extern int dwarf_always_disassemble
;
44 extern const struct dwarf_expr_context_funcs dwarf_expr_ctx_funcs
;
46 static struct value
*dwarf2_evaluate_loc_desc_full (struct type
*type
,
47 struct frame_info
*frame
,
50 struct dwarf2_per_cu_data
*per_cu
,
53 /* Until these have formal names, we define these here.
54 ref: http://gcc.gnu.org/wiki/DebugFission
55 Each entry in .debug_loc.dwo begins with a byte that describes the entry,
56 and is then followed by data specific to that entry. */
60 /* Indicates the end of the list of entries. */
61 DEBUG_LOC_END_OF_LIST
= 0,
63 /* This is followed by an unsigned LEB128 number that is an index into
64 .debug_addr and specifies the base address for all following entries. */
65 DEBUG_LOC_BASE_ADDRESS
= 1,
67 /* This is followed by two unsigned LEB128 numbers that are indices into
68 .debug_addr and specify the beginning and ending addresses, and then
69 a normal location expression as in .debug_loc. */
70 DEBUG_LOC_START_END
= 2,
72 /* This is followed by an unsigned LEB128 number that is an index into
73 .debug_addr and specifies the beginning address, and a 4 byte unsigned
74 number that specifies the length, and then a normal location expression
76 DEBUG_LOC_START_LENGTH
= 3,
78 /* An internal value indicating there is insufficient data. */
79 DEBUG_LOC_BUFFER_OVERFLOW
= -1,
81 /* An internal value indicating an invalid kind of entry was found. */
82 DEBUG_LOC_INVALID_ENTRY
= -2
85 /* Helper function which throws an error if a synthetic pointer is
89 invalid_synthetic_pointer (void)
91 error (_("access outside bounds of object "
92 "referenced via synthetic pointer"));
95 /* Decode the addresses in a non-dwo .debug_loc entry.
96 A pointer to the next byte to examine is returned in *NEW_PTR.
97 The encoded low,high addresses are return in *LOW,*HIGH.
98 The result indicates the kind of entry found. */
100 static enum debug_loc_kind
101 decode_debug_loc_addresses (const gdb_byte
*loc_ptr
, const gdb_byte
*buf_end
,
102 const gdb_byte
**new_ptr
,
103 CORE_ADDR
*low
, CORE_ADDR
*high
,
104 enum bfd_endian byte_order
,
105 unsigned int addr_size
,
108 CORE_ADDR base_mask
= ~(~(CORE_ADDR
)1 << (addr_size
* 8 - 1));
110 if (buf_end
- loc_ptr
< 2 * addr_size
)
111 return DEBUG_LOC_BUFFER_OVERFLOW
;
114 *low
= extract_signed_integer (loc_ptr
, addr_size
, byte_order
);
116 *low
= extract_unsigned_integer (loc_ptr
, addr_size
, byte_order
);
117 loc_ptr
+= addr_size
;
120 *high
= extract_signed_integer (loc_ptr
, addr_size
, byte_order
);
122 *high
= extract_unsigned_integer (loc_ptr
, addr_size
, byte_order
);
123 loc_ptr
+= addr_size
;
127 /* A base-address-selection entry. */
128 if ((*low
& base_mask
) == base_mask
)
129 return DEBUG_LOC_BASE_ADDRESS
;
131 /* An end-of-list entry. */
132 if (*low
== 0 && *high
== 0)
133 return DEBUG_LOC_END_OF_LIST
;
135 return DEBUG_LOC_START_END
;
138 /* Decode the addresses in .debug_loc.dwo entry.
139 A pointer to the next byte to examine is returned in *NEW_PTR.
140 The encoded low,high addresses are return in *LOW,*HIGH.
141 The result indicates the kind of entry found. */
143 static enum debug_loc_kind
144 decode_debug_loc_dwo_addresses (struct dwarf2_per_cu_data
*per_cu
,
145 const gdb_byte
*loc_ptr
,
146 const gdb_byte
*buf_end
,
147 const gdb_byte
**new_ptr
,
148 CORE_ADDR
*low
, CORE_ADDR
*high
,
149 enum bfd_endian byte_order
)
151 uint64_t low_index
, high_index
;
153 if (loc_ptr
== buf_end
)
154 return DEBUG_LOC_BUFFER_OVERFLOW
;
158 case DEBUG_LOC_END_OF_LIST
:
160 return DEBUG_LOC_END_OF_LIST
;
161 case DEBUG_LOC_BASE_ADDRESS
:
163 loc_ptr
= gdb_read_uleb128 (loc_ptr
, buf_end
, &high_index
);
165 return DEBUG_LOC_BUFFER_OVERFLOW
;
166 *high
= dwarf2_read_addr_index (per_cu
, high_index
);
168 return DEBUG_LOC_BASE_ADDRESS
;
169 case DEBUG_LOC_START_END
:
170 loc_ptr
= gdb_read_uleb128 (loc_ptr
, buf_end
, &low_index
);
172 return DEBUG_LOC_BUFFER_OVERFLOW
;
173 *low
= dwarf2_read_addr_index (per_cu
, low_index
);
174 loc_ptr
= gdb_read_uleb128 (loc_ptr
, buf_end
, &high_index
);
176 return DEBUG_LOC_BUFFER_OVERFLOW
;
177 *high
= dwarf2_read_addr_index (per_cu
, high_index
);
179 return DEBUG_LOC_START_END
;
180 case DEBUG_LOC_START_LENGTH
:
181 loc_ptr
= gdb_read_uleb128 (loc_ptr
, buf_end
, &low_index
);
183 return DEBUG_LOC_BUFFER_OVERFLOW
;
184 *low
= dwarf2_read_addr_index (per_cu
, low_index
);
185 if (loc_ptr
+ 4 > buf_end
)
186 return DEBUG_LOC_BUFFER_OVERFLOW
;
188 *high
+= extract_unsigned_integer (loc_ptr
, 4, byte_order
);
189 *new_ptr
= loc_ptr
+ 4;
190 return DEBUG_LOC_START_LENGTH
;
192 return DEBUG_LOC_INVALID_ENTRY
;
196 /* A function for dealing with location lists. Given a
197 symbol baton (BATON) and a pc value (PC), find the appropriate
198 location expression, set *LOCEXPR_LENGTH, and return a pointer
199 to the beginning of the expression. Returns NULL on failure.
201 For now, only return the first matching location expression; there
202 can be more than one in the list. */
205 dwarf2_find_location_expression (struct dwarf2_loclist_baton
*baton
,
206 size_t *locexpr_length
, CORE_ADDR pc
)
208 struct objfile
*objfile
= dwarf2_per_cu_objfile (baton
->per_cu
);
209 struct gdbarch
*gdbarch
= get_objfile_arch (objfile
);
210 enum bfd_endian byte_order
= gdbarch_byte_order (gdbarch
);
211 unsigned int addr_size
= dwarf2_per_cu_addr_size (baton
->per_cu
);
212 int signed_addr_p
= bfd_get_sign_extend_vma (objfile
->obfd
);
213 /* Adjust base_address for relocatable objects. */
214 CORE_ADDR base_offset
= dwarf2_per_cu_text_offset (baton
->per_cu
);
215 CORE_ADDR base_address
= baton
->base_address
+ base_offset
;
216 const gdb_byte
*loc_ptr
, *buf_end
;
218 loc_ptr
= baton
->data
;
219 buf_end
= baton
->data
+ baton
->size
;
223 CORE_ADDR low
= 0, high
= 0; /* init for gcc -Wall */
225 enum debug_loc_kind kind
;
226 const gdb_byte
*new_ptr
= NULL
; /* init for gcc -Wall */
229 kind
= decode_debug_loc_dwo_addresses (baton
->per_cu
,
230 loc_ptr
, buf_end
, &new_ptr
,
231 &low
, &high
, byte_order
);
233 kind
= decode_debug_loc_addresses (loc_ptr
, buf_end
, &new_ptr
,
235 byte_order
, addr_size
,
240 case DEBUG_LOC_END_OF_LIST
:
243 case DEBUG_LOC_BASE_ADDRESS
:
244 base_address
= high
+ base_offset
;
246 case DEBUG_LOC_START_END
:
247 case DEBUG_LOC_START_LENGTH
:
249 case DEBUG_LOC_BUFFER_OVERFLOW
:
250 case DEBUG_LOC_INVALID_ENTRY
:
251 error (_("dwarf2_find_location_expression: "
252 "Corrupted DWARF expression."));
254 gdb_assert_not_reached ("bad debug_loc_kind");
257 /* Otherwise, a location expression entry.
258 If the entry is from a DWO, don't add base address: the entry is from
259 .debug_addr which already has the DWARF "base address". We still add
260 base_offset in case we're debugging a PIE executable. */
269 high
+= base_address
;
272 length
= extract_unsigned_integer (loc_ptr
, 2, byte_order
);
275 if (low
== high
&& pc
== low
)
277 /* This is entry PC record present only at entry point
278 of a function. Verify it is really the function entry point. */
280 const struct block
*pc_block
= block_for_pc (pc
);
281 struct symbol
*pc_func
= NULL
;
284 pc_func
= block_linkage_function (pc_block
);
286 if (pc_func
&& pc
== BLOCK_START (SYMBOL_BLOCK_VALUE (pc_func
)))
288 *locexpr_length
= length
;
293 if (pc
>= low
&& pc
< high
)
295 *locexpr_length
= length
;
303 /* This is the baton used when performing dwarf2 expression
305 struct dwarf_expr_baton
307 struct frame_info
*frame
;
308 struct dwarf2_per_cu_data
*per_cu
;
309 CORE_ADDR obj_address
;
312 /* Helper functions for dwarf2_evaluate_loc_desc. */
314 /* Using the frame specified in BATON, return the value of register
315 REGNUM, treated as a pointer. */
317 dwarf_expr_read_addr_from_reg (void *baton
, int dwarf_regnum
)
319 struct dwarf_expr_baton
*debaton
= (struct dwarf_expr_baton
*) baton
;
320 struct gdbarch
*gdbarch
= get_frame_arch (debaton
->frame
);
321 int regnum
= dwarf_reg_to_regnum_or_error (gdbarch
, dwarf_regnum
);
323 return address_from_register (regnum
, debaton
->frame
);
326 /* Implement struct dwarf_expr_context_funcs' "get_reg_value" callback. */
328 static struct value
*
329 dwarf_expr_get_reg_value (void *baton
, struct type
*type
, int dwarf_regnum
)
331 struct dwarf_expr_baton
*debaton
= (struct dwarf_expr_baton
*) baton
;
332 struct gdbarch
*gdbarch
= get_frame_arch (debaton
->frame
);
333 int regnum
= dwarf_reg_to_regnum_or_error (gdbarch
, dwarf_regnum
);
335 return value_from_register (type
, regnum
, debaton
->frame
);
338 /* Read memory at ADDR (length LEN) into BUF. */
341 dwarf_expr_read_mem (void *baton
, gdb_byte
*buf
, CORE_ADDR addr
, size_t len
)
343 read_memory (addr
, buf
, len
);
346 /* Using the frame specified in BATON, find the location expression
347 describing the frame base. Return a pointer to it in START and
348 its length in LENGTH. */
350 dwarf_expr_frame_base (void *baton
, const gdb_byte
**start
, size_t * length
)
352 /* FIXME: cagney/2003-03-26: This code should be using
353 get_frame_base_address(), and then implement a dwarf2 specific
355 struct symbol
*framefunc
;
356 struct dwarf_expr_baton
*debaton
= (struct dwarf_expr_baton
*) baton
;
357 const struct block
*bl
= get_frame_block (debaton
->frame
, NULL
);
360 error (_("frame address is not available."));
362 /* Use block_linkage_function, which returns a real (not inlined)
363 function, instead of get_frame_function, which may return an
365 framefunc
= block_linkage_function (bl
);
367 /* If we found a frame-relative symbol then it was certainly within
368 some function associated with a frame. If we can't find the frame,
369 something has gone wrong. */
370 gdb_assert (framefunc
!= NULL
);
372 func_get_frame_base_dwarf_block (framefunc
,
373 get_frame_address_in_block (debaton
->frame
),
377 /* Implement find_frame_base_location method for LOC_BLOCK functions using
378 DWARF expression for its DW_AT_frame_base. */
381 locexpr_find_frame_base_location (struct symbol
*framefunc
, CORE_ADDR pc
,
382 const gdb_byte
**start
, size_t *length
)
384 struct dwarf2_locexpr_baton
*symbaton
385 = (struct dwarf2_locexpr_baton
*) SYMBOL_LOCATION_BATON (framefunc
);
387 *length
= symbaton
->size
;
388 *start
= symbaton
->data
;
391 /* Implement the struct symbol_block_ops::get_frame_base method for
392 LOC_BLOCK functions using a DWARF expression as its DW_AT_frame_base. */
395 locexpr_get_frame_base (struct symbol
*framefunc
, struct frame_info
*frame
)
397 struct gdbarch
*gdbarch
;
399 struct dwarf2_locexpr_baton
*dlbaton
;
400 const gdb_byte
*start
;
402 struct value
*result
;
404 /* If this method is called, then FRAMEFUNC is supposed to be a DWARF block.
405 Thus, it's supposed to provide the find_frame_base_location method as
407 gdb_assert (SYMBOL_BLOCK_OPS (framefunc
)->find_frame_base_location
!= NULL
);
409 gdbarch
= get_frame_arch (frame
);
410 type
= builtin_type (gdbarch
)->builtin_data_ptr
;
411 dlbaton
= (struct dwarf2_locexpr_baton
*) SYMBOL_LOCATION_BATON (framefunc
);
413 SYMBOL_BLOCK_OPS (framefunc
)->find_frame_base_location
414 (framefunc
, get_frame_pc (frame
), &start
, &length
);
415 result
= dwarf2_evaluate_loc_desc (type
, frame
, start
, length
,
418 /* The DW_AT_frame_base attribute contains a location description which
419 computes the base address itself. However, the call to
420 dwarf2_evaluate_loc_desc returns a value representing a variable at
421 that address. The frame base address is thus this variable's
423 return value_address (result
);
426 /* Vector for inferior functions as represented by LOC_BLOCK, if the inferior
427 function uses DWARF expression for its DW_AT_frame_base. */
429 const struct symbol_block_ops dwarf2_block_frame_base_locexpr_funcs
=
431 locexpr_find_frame_base_location
,
432 locexpr_get_frame_base
435 /* Implement find_frame_base_location method for LOC_BLOCK functions using
436 DWARF location list for its DW_AT_frame_base. */
439 loclist_find_frame_base_location (struct symbol
*framefunc
, CORE_ADDR pc
,
440 const gdb_byte
**start
, size_t *length
)
442 struct dwarf2_loclist_baton
*symbaton
443 = (struct dwarf2_loclist_baton
*) SYMBOL_LOCATION_BATON (framefunc
);
445 *start
= dwarf2_find_location_expression (symbaton
, length
, pc
);
448 /* Implement the struct symbol_block_ops::get_frame_base method for
449 LOC_BLOCK functions using a DWARF location list as its DW_AT_frame_base. */
452 loclist_get_frame_base (struct symbol
*framefunc
, struct frame_info
*frame
)
454 struct gdbarch
*gdbarch
;
456 struct dwarf2_loclist_baton
*dlbaton
;
457 const gdb_byte
*start
;
459 struct value
*result
;
461 /* If this method is called, then FRAMEFUNC is supposed to be a DWARF block.
462 Thus, it's supposed to provide the find_frame_base_location method as
464 gdb_assert (SYMBOL_BLOCK_OPS (framefunc
)->find_frame_base_location
!= NULL
);
466 gdbarch
= get_frame_arch (frame
);
467 type
= builtin_type (gdbarch
)->builtin_data_ptr
;
468 dlbaton
= (struct dwarf2_loclist_baton
*) SYMBOL_LOCATION_BATON (framefunc
);
470 SYMBOL_BLOCK_OPS (framefunc
)->find_frame_base_location
471 (framefunc
, get_frame_pc (frame
), &start
, &length
);
472 result
= dwarf2_evaluate_loc_desc (type
, frame
, start
, length
,
475 /* The DW_AT_frame_base attribute contains a location description which
476 computes the base address itself. However, the call to
477 dwarf2_evaluate_loc_desc returns a value representing a variable at
478 that address. The frame base address is thus this variable's
480 return value_address (result
);
483 /* Vector for inferior functions as represented by LOC_BLOCK, if the inferior
484 function uses DWARF location list for its DW_AT_frame_base. */
486 const struct symbol_block_ops dwarf2_block_frame_base_loclist_funcs
=
488 loclist_find_frame_base_location
,
489 loclist_get_frame_base
492 /* See dwarf2loc.h. */
495 func_get_frame_base_dwarf_block (struct symbol
*framefunc
, CORE_ADDR pc
,
496 const gdb_byte
**start
, size_t *length
)
498 if (SYMBOL_BLOCK_OPS (framefunc
) != NULL
)
500 const struct symbol_block_ops
*ops_block
= SYMBOL_BLOCK_OPS (framefunc
);
502 ops_block
->find_frame_base_location (framefunc
, pc
, start
, length
);
508 error (_("Could not find the frame base for \"%s\"."),
509 SYMBOL_NATURAL_NAME (framefunc
));
512 /* Helper function for dwarf2_evaluate_loc_desc. Computes the CFA for
513 the frame in BATON. */
516 dwarf_expr_frame_cfa (void *baton
)
518 struct dwarf_expr_baton
*debaton
= (struct dwarf_expr_baton
*) baton
;
520 return dwarf2_frame_cfa (debaton
->frame
);
523 /* Helper function for dwarf2_evaluate_loc_desc. Computes the PC for
524 the frame in BATON. */
527 dwarf_expr_frame_pc (void *baton
)
529 struct dwarf_expr_baton
*debaton
= (struct dwarf_expr_baton
*) baton
;
531 return get_frame_address_in_block (debaton
->frame
);
534 /* Using the objfile specified in BATON, find the address for the
535 current thread's thread-local storage with offset OFFSET. */
537 dwarf_expr_tls_address (void *baton
, CORE_ADDR offset
)
539 struct dwarf_expr_baton
*debaton
= (struct dwarf_expr_baton
*) baton
;
540 struct objfile
*objfile
= dwarf2_per_cu_objfile (debaton
->per_cu
);
542 return target_translate_tls_address (objfile
, offset
);
545 /* Call DWARF subroutine from DW_AT_location of DIE at DIE_OFFSET in
546 current CU (as is PER_CU). State of the CTX is not affected by the
550 per_cu_dwarf_call (struct dwarf_expr_context
*ctx
, cu_offset die_offset
,
551 struct dwarf2_per_cu_data
*per_cu
,
552 CORE_ADDR (*get_frame_pc
) (void *baton
),
555 struct dwarf2_locexpr_baton block
;
557 block
= dwarf2_fetch_die_loc_cu_off (die_offset
, per_cu
, get_frame_pc
, baton
);
559 /* DW_OP_call_ref is currently not supported. */
560 gdb_assert (block
.per_cu
== per_cu
);
562 dwarf_expr_eval (ctx
, block
.data
, block
.size
);
565 /* Helper interface of per_cu_dwarf_call for dwarf2_evaluate_loc_desc. */
568 dwarf_expr_dwarf_call (struct dwarf_expr_context
*ctx
, cu_offset die_offset
)
570 struct dwarf_expr_baton
*debaton
= (struct dwarf_expr_baton
*) ctx
->baton
;
572 per_cu_dwarf_call (ctx
, die_offset
, debaton
->per_cu
,
573 ctx
->funcs
->get_frame_pc
, ctx
->baton
);
576 /* Callback function for dwarf2_evaluate_loc_desc. */
579 dwarf_expr_get_base_type (struct dwarf_expr_context
*ctx
,
580 cu_offset die_offset
)
582 struct dwarf_expr_baton
*debaton
= (struct dwarf_expr_baton
*) ctx
->baton
;
584 return dwarf2_get_die_type (die_offset
, debaton
->per_cu
);
587 /* See dwarf2loc.h. */
589 unsigned int entry_values_debug
= 0;
591 /* Helper to set entry_values_debug. */
594 show_entry_values_debug (struct ui_file
*file
, int from_tty
,
595 struct cmd_list_element
*c
, const char *value
)
597 fprintf_filtered (file
,
598 _("Entry values and tail call frames debugging is %s.\n"),
602 /* Find DW_TAG_GNU_call_site's DW_AT_GNU_call_site_target address.
603 CALLER_FRAME (for registers) can be NULL if it is not known. This function
604 always returns valid address or it throws NO_ENTRY_VALUE_ERROR. */
607 call_site_to_target_addr (struct gdbarch
*call_site_gdbarch
,
608 struct call_site
*call_site
,
609 struct frame_info
*caller_frame
)
611 switch (FIELD_LOC_KIND (call_site
->target
))
613 case FIELD_LOC_KIND_DWARF_BLOCK
:
615 struct dwarf2_locexpr_baton
*dwarf_block
;
617 struct type
*caller_core_addr_type
;
618 struct gdbarch
*caller_arch
;
620 dwarf_block
= FIELD_DWARF_BLOCK (call_site
->target
);
621 if (dwarf_block
== NULL
)
623 struct bound_minimal_symbol msym
;
625 msym
= lookup_minimal_symbol_by_pc (call_site
->pc
- 1);
626 throw_error (NO_ENTRY_VALUE_ERROR
,
627 _("DW_AT_GNU_call_site_target is not specified "
629 paddress (call_site_gdbarch
, call_site
->pc
),
630 (msym
.minsym
== NULL
? "???"
631 : MSYMBOL_PRINT_NAME (msym
.minsym
)));
634 if (caller_frame
== NULL
)
636 struct bound_minimal_symbol msym
;
638 msym
= lookup_minimal_symbol_by_pc (call_site
->pc
- 1);
639 throw_error (NO_ENTRY_VALUE_ERROR
,
640 _("DW_AT_GNU_call_site_target DWARF block resolving "
641 "requires known frame which is currently not "
642 "available at %s in %s"),
643 paddress (call_site_gdbarch
, call_site
->pc
),
644 (msym
.minsym
== NULL
? "???"
645 : MSYMBOL_PRINT_NAME (msym
.minsym
)));
648 caller_arch
= get_frame_arch (caller_frame
);
649 caller_core_addr_type
= builtin_type (caller_arch
)->builtin_func_ptr
;
650 val
= dwarf2_evaluate_loc_desc (caller_core_addr_type
, caller_frame
,
651 dwarf_block
->data
, dwarf_block
->size
,
652 dwarf_block
->per_cu
);
653 /* DW_AT_GNU_call_site_target is a DWARF expression, not a DWARF
655 if (VALUE_LVAL (val
) == lval_memory
)
656 return value_address (val
);
658 return value_as_address (val
);
661 case FIELD_LOC_KIND_PHYSNAME
:
663 const char *physname
;
664 struct bound_minimal_symbol msym
;
666 physname
= FIELD_STATIC_PHYSNAME (call_site
->target
);
668 /* Handle both the mangled and demangled PHYSNAME. */
669 msym
= lookup_minimal_symbol (physname
, NULL
, NULL
);
670 if (msym
.minsym
== NULL
)
672 msym
= lookup_minimal_symbol_by_pc (call_site
->pc
- 1);
673 throw_error (NO_ENTRY_VALUE_ERROR
,
674 _("Cannot find function \"%s\" for a call site target "
676 physname
, paddress (call_site_gdbarch
, call_site
->pc
),
677 (msym
.minsym
== NULL
? "???"
678 : MSYMBOL_PRINT_NAME (msym
.minsym
)));
681 return BMSYMBOL_VALUE_ADDRESS (msym
);
684 case FIELD_LOC_KIND_PHYSADDR
:
685 return FIELD_STATIC_PHYSADDR (call_site
->target
);
688 internal_error (__FILE__
, __LINE__
, _("invalid call site target kind"));
692 /* Convert function entry point exact address ADDR to the function which is
693 compliant with TAIL_CALL_LIST_COMPLETE condition. Throw
694 NO_ENTRY_VALUE_ERROR otherwise. */
696 static struct symbol
*
697 func_addr_to_tail_call_list (struct gdbarch
*gdbarch
, CORE_ADDR addr
)
699 struct symbol
*sym
= find_pc_function (addr
);
702 if (sym
== NULL
|| BLOCK_START (SYMBOL_BLOCK_VALUE (sym
)) != addr
)
703 throw_error (NO_ENTRY_VALUE_ERROR
,
704 _("DW_TAG_GNU_call_site resolving failed to find function "
705 "name for address %s"),
706 paddress (gdbarch
, addr
));
708 type
= SYMBOL_TYPE (sym
);
709 gdb_assert (TYPE_CODE (type
) == TYPE_CODE_FUNC
);
710 gdb_assert (TYPE_SPECIFIC_FIELD (type
) == TYPE_SPECIFIC_FUNC
);
715 /* Verify function with entry point exact address ADDR can never call itself
716 via its tail calls (incl. transitively). Throw NO_ENTRY_VALUE_ERROR if it
717 can call itself via tail calls.
719 If a funtion can tail call itself its entry value based parameters are
720 unreliable. There is no verification whether the value of some/all
721 parameters is unchanged through the self tail call, we expect if there is
722 a self tail call all the parameters can be modified. */
725 func_verify_no_selftailcall (struct gdbarch
*gdbarch
, CORE_ADDR verify_addr
)
727 struct obstack addr_obstack
;
728 struct cleanup
*old_chain
;
731 /* Track here CORE_ADDRs which were already visited. */
734 /* The verification is completely unordered. Track here function addresses
735 which still need to be iterated. */
736 VEC (CORE_ADDR
) *todo
= NULL
;
738 obstack_init (&addr_obstack
);
739 old_chain
= make_cleanup_obstack_free (&addr_obstack
);
740 addr_hash
= htab_create_alloc_ex (64, core_addr_hash
, core_addr_eq
, NULL
,
741 &addr_obstack
, hashtab_obstack_allocate
,
743 make_cleanup_htab_delete (addr_hash
);
745 make_cleanup (VEC_cleanup (CORE_ADDR
), &todo
);
747 VEC_safe_push (CORE_ADDR
, todo
, verify_addr
);
748 while (!VEC_empty (CORE_ADDR
, todo
))
750 struct symbol
*func_sym
;
751 struct call_site
*call_site
;
753 addr
= VEC_pop (CORE_ADDR
, todo
);
755 func_sym
= func_addr_to_tail_call_list (gdbarch
, addr
);
757 for (call_site
= TYPE_TAIL_CALL_LIST (SYMBOL_TYPE (func_sym
));
758 call_site
; call_site
= call_site
->tail_call_next
)
760 CORE_ADDR target_addr
;
763 /* CALLER_FRAME with registers is not available for tail-call jumped
765 target_addr
= call_site_to_target_addr (gdbarch
, call_site
, NULL
);
767 if (target_addr
== verify_addr
)
769 struct bound_minimal_symbol msym
;
771 msym
= lookup_minimal_symbol_by_pc (verify_addr
);
772 throw_error (NO_ENTRY_VALUE_ERROR
,
773 _("DW_OP_GNU_entry_value resolving has found "
774 "function \"%s\" at %s can call itself via tail "
776 (msym
.minsym
== NULL
? "???"
777 : MSYMBOL_PRINT_NAME (msym
.minsym
)),
778 paddress (gdbarch
, verify_addr
));
781 slot
= htab_find_slot (addr_hash
, &target_addr
, INSERT
);
784 *slot
= obstack_copy (&addr_obstack
, &target_addr
,
785 sizeof (target_addr
));
786 VEC_safe_push (CORE_ADDR
, todo
, target_addr
);
791 do_cleanups (old_chain
);
794 /* Print user readable form of CALL_SITE->PC to gdb_stdlog. Used only for
795 ENTRY_VALUES_DEBUG. */
798 tailcall_dump (struct gdbarch
*gdbarch
, const struct call_site
*call_site
)
800 CORE_ADDR addr
= call_site
->pc
;
801 struct bound_minimal_symbol msym
= lookup_minimal_symbol_by_pc (addr
- 1);
803 fprintf_unfiltered (gdb_stdlog
, " %s(%s)", paddress (gdbarch
, addr
),
804 (msym
.minsym
== NULL
? "???"
805 : MSYMBOL_PRINT_NAME (msym
.minsym
)));
809 /* vec.h needs single word type name, typedef it. */
810 typedef struct call_site
*call_sitep
;
812 /* Define VEC (call_sitep) functions. */
813 DEF_VEC_P (call_sitep
);
815 /* Intersect RESULTP with CHAIN to keep RESULTP unambiguous, keep in RESULTP
816 only top callers and bottom callees which are present in both. GDBARCH is
817 used only for ENTRY_VALUES_DEBUG. RESULTP is NULL after return if there are
818 no remaining possibilities to provide unambiguous non-trivial result.
819 RESULTP should point to NULL on the first (initialization) call. Caller is
820 responsible for xfree of any RESULTP data. */
823 chain_candidate (struct gdbarch
*gdbarch
, struct call_site_chain
**resultp
,
824 VEC (call_sitep
) *chain
)
826 struct call_site_chain
*result
= *resultp
;
827 long length
= VEC_length (call_sitep
, chain
);
828 int callers
, callees
, idx
;
832 /* Create the initial chain containing all the passed PCs. */
834 result
= ((struct call_site_chain
*)
835 xmalloc (sizeof (*result
)
836 + sizeof (*result
->call_site
) * (length
- 1)));
837 result
->length
= length
;
838 result
->callers
= result
->callees
= length
;
839 if (!VEC_empty (call_sitep
, chain
))
840 memcpy (result
->call_site
, VEC_address (call_sitep
, chain
),
841 sizeof (*result
->call_site
) * length
);
844 if (entry_values_debug
)
846 fprintf_unfiltered (gdb_stdlog
, "tailcall: initial:");
847 for (idx
= 0; idx
< length
; idx
++)
848 tailcall_dump (gdbarch
, result
->call_site
[idx
]);
849 fputc_unfiltered ('\n', gdb_stdlog
);
855 if (entry_values_debug
)
857 fprintf_unfiltered (gdb_stdlog
, "tailcall: compare:");
858 for (idx
= 0; idx
< length
; idx
++)
859 tailcall_dump (gdbarch
, VEC_index (call_sitep
, chain
, idx
));
860 fputc_unfiltered ('\n', gdb_stdlog
);
863 /* Intersect callers. */
865 callers
= min (result
->callers
, length
);
866 for (idx
= 0; idx
< callers
; idx
++)
867 if (result
->call_site
[idx
] != VEC_index (call_sitep
, chain
, idx
))
869 result
->callers
= idx
;
873 /* Intersect callees. */
875 callees
= min (result
->callees
, length
);
876 for (idx
= 0; idx
< callees
; idx
++)
877 if (result
->call_site
[result
->length
- 1 - idx
]
878 != VEC_index (call_sitep
, chain
, length
- 1 - idx
))
880 result
->callees
= idx
;
884 if (entry_values_debug
)
886 fprintf_unfiltered (gdb_stdlog
, "tailcall: reduced:");
887 for (idx
= 0; idx
< result
->callers
; idx
++)
888 tailcall_dump (gdbarch
, result
->call_site
[idx
]);
889 fputs_unfiltered (" |", gdb_stdlog
);
890 for (idx
= 0; idx
< result
->callees
; idx
++)
891 tailcall_dump (gdbarch
, result
->call_site
[result
->length
892 - result
->callees
+ idx
]);
893 fputc_unfiltered ('\n', gdb_stdlog
);
896 if (result
->callers
== 0 && result
->callees
== 0)
898 /* There are no common callers or callees. It could be also a direct
899 call (which has length 0) with ambiguous possibility of an indirect
900 call - CALLERS == CALLEES == 0 is valid during the first allocation
901 but any subsequence processing of such entry means ambiguity. */
907 /* See call_site_find_chain_1 why there is no way to reach the bottom callee
908 PC again. In such case there must be two different code paths to reach
909 it. CALLERS + CALLEES equal to LENGTH in the case of self tail-call. */
910 gdb_assert (result
->callers
+ result
->callees
<= result
->length
);
913 /* Create and return call_site_chain for CALLER_PC and CALLEE_PC. All the
914 assumed frames between them use GDBARCH. Use depth first search so we can
915 keep single CHAIN of call_site's back to CALLER_PC. Function recursion
916 would have needless GDB stack overhead. Caller is responsible for xfree of
917 the returned result. Any unreliability results in thrown
918 NO_ENTRY_VALUE_ERROR. */
920 static struct call_site_chain
*
921 call_site_find_chain_1 (struct gdbarch
*gdbarch
, CORE_ADDR caller_pc
,
924 CORE_ADDR save_callee_pc
= callee_pc
;
925 struct obstack addr_obstack
;
926 struct cleanup
*back_to_retval
, *back_to_workdata
;
927 struct call_site_chain
*retval
= NULL
;
928 struct call_site
*call_site
;
930 /* Mark CALL_SITEs so we do not visit the same ones twice. */
933 /* CHAIN contains only the intermediate CALL_SITEs. Neither CALLER_PC's
934 call_site nor any possible call_site at CALLEE_PC's function is there.
935 Any CALL_SITE in CHAIN will be iterated to its siblings - via
936 TAIL_CALL_NEXT. This is inappropriate for CALLER_PC's call_site. */
937 VEC (call_sitep
) *chain
= NULL
;
939 /* We are not interested in the specific PC inside the callee function. */
940 callee_pc
= get_pc_function_start (callee_pc
);
942 throw_error (NO_ENTRY_VALUE_ERROR
, _("Unable to find function for PC %s"),
943 paddress (gdbarch
, save_callee_pc
));
945 back_to_retval
= make_cleanup (free_current_contents
, &retval
);
947 obstack_init (&addr_obstack
);
948 back_to_workdata
= make_cleanup_obstack_free (&addr_obstack
);
949 addr_hash
= htab_create_alloc_ex (64, core_addr_hash
, core_addr_eq
, NULL
,
950 &addr_obstack
, hashtab_obstack_allocate
,
952 make_cleanup_htab_delete (addr_hash
);
954 make_cleanup (VEC_cleanup (call_sitep
), &chain
);
956 /* Do not push CALL_SITE to CHAIN. Push there only the first tail call site
957 at the target's function. All the possible tail call sites in the
958 target's function will get iterated as already pushed into CHAIN via their
960 call_site
= call_site_for_pc (gdbarch
, caller_pc
);
964 CORE_ADDR target_func_addr
;
965 struct call_site
*target_call_site
;
967 /* CALLER_FRAME with registers is not available for tail-call jumped
969 target_func_addr
= call_site_to_target_addr (gdbarch
, call_site
, NULL
);
971 if (target_func_addr
== callee_pc
)
973 chain_candidate (gdbarch
, &retval
, chain
);
977 /* There is no way to reach CALLEE_PC again as we would prevent
978 entering it twice as being already marked in ADDR_HASH. */
979 target_call_site
= NULL
;
983 struct symbol
*target_func
;
985 target_func
= func_addr_to_tail_call_list (gdbarch
, target_func_addr
);
986 target_call_site
= TYPE_TAIL_CALL_LIST (SYMBOL_TYPE (target_func
));
991 /* Attempt to visit TARGET_CALL_SITE. */
993 if (target_call_site
)
997 slot
= htab_find_slot (addr_hash
, &target_call_site
->pc
, INSERT
);
1000 /* Successfully entered TARGET_CALL_SITE. */
1002 *slot
= &target_call_site
->pc
;
1003 VEC_safe_push (call_sitep
, chain
, target_call_site
);
1008 /* Backtrack (without revisiting the originating call_site). Try the
1009 callers's sibling; if there isn't any try the callers's callers's
1012 target_call_site
= NULL
;
1013 while (!VEC_empty (call_sitep
, chain
))
1015 call_site
= VEC_pop (call_sitep
, chain
);
1017 gdb_assert (htab_find_slot (addr_hash
, &call_site
->pc
,
1018 NO_INSERT
) != NULL
);
1019 htab_remove_elt (addr_hash
, &call_site
->pc
);
1021 target_call_site
= call_site
->tail_call_next
;
1022 if (target_call_site
)
1026 while (target_call_site
);
1028 if (VEC_empty (call_sitep
, chain
))
1031 call_site
= VEC_last (call_sitep
, chain
);
1036 struct bound_minimal_symbol msym_caller
, msym_callee
;
1038 msym_caller
= lookup_minimal_symbol_by_pc (caller_pc
);
1039 msym_callee
= lookup_minimal_symbol_by_pc (callee_pc
);
1040 throw_error (NO_ENTRY_VALUE_ERROR
,
1041 _("There are no unambiguously determinable intermediate "
1042 "callers or callees between caller function \"%s\" at %s "
1043 "and callee function \"%s\" at %s"),
1044 (msym_caller
.minsym
== NULL
1045 ? "???" : MSYMBOL_PRINT_NAME (msym_caller
.minsym
)),
1046 paddress (gdbarch
, caller_pc
),
1047 (msym_callee
.minsym
== NULL
1048 ? "???" : MSYMBOL_PRINT_NAME (msym_callee
.minsym
)),
1049 paddress (gdbarch
, callee_pc
));
1052 do_cleanups (back_to_workdata
);
1053 discard_cleanups (back_to_retval
);
1057 /* Create and return call_site_chain for CALLER_PC and CALLEE_PC. All the
1058 assumed frames between them use GDBARCH. If valid call_site_chain cannot be
1059 constructed return NULL. Caller is responsible for xfree of the returned
1062 struct call_site_chain
*
1063 call_site_find_chain (struct gdbarch
*gdbarch
, CORE_ADDR caller_pc
,
1064 CORE_ADDR callee_pc
)
1066 struct call_site_chain
*retval
= NULL
;
1070 retval
= call_site_find_chain_1 (gdbarch
, caller_pc
, callee_pc
);
1072 CATCH (e
, RETURN_MASK_ERROR
)
1074 if (e
.error
== NO_ENTRY_VALUE_ERROR
)
1076 if (entry_values_debug
)
1077 exception_print (gdb_stdout
, e
);
1082 throw_exception (e
);
1089 /* Return 1 if KIND and KIND_U match PARAMETER. Return 0 otherwise. */
1092 call_site_parameter_matches (struct call_site_parameter
*parameter
,
1093 enum call_site_parameter_kind kind
,
1094 union call_site_parameter_u kind_u
)
1096 if (kind
== parameter
->kind
)
1099 case CALL_SITE_PARAMETER_DWARF_REG
:
1100 return kind_u
.dwarf_reg
== parameter
->u
.dwarf_reg
;
1101 case CALL_SITE_PARAMETER_FB_OFFSET
:
1102 return kind_u
.fb_offset
== parameter
->u
.fb_offset
;
1103 case CALL_SITE_PARAMETER_PARAM_OFFSET
:
1104 return kind_u
.param_offset
.cu_off
== parameter
->u
.param_offset
.cu_off
;
1109 /* Fetch call_site_parameter from caller matching KIND and KIND_U.
1110 FRAME is for callee.
1112 Function always returns non-NULL, it throws NO_ENTRY_VALUE_ERROR
1115 static struct call_site_parameter
*
1116 dwarf_expr_reg_to_entry_parameter (struct frame_info
*frame
,
1117 enum call_site_parameter_kind kind
,
1118 union call_site_parameter_u kind_u
,
1119 struct dwarf2_per_cu_data
**per_cu_return
)
1121 CORE_ADDR func_addr
, caller_pc
;
1122 struct gdbarch
*gdbarch
;
1123 struct frame_info
*caller_frame
;
1124 struct call_site
*call_site
;
1126 /* Initialize it just to avoid a GCC false warning. */
1127 struct call_site_parameter
*parameter
= NULL
;
1128 CORE_ADDR target_addr
;
1130 while (get_frame_type (frame
) == INLINE_FRAME
)
1132 frame
= get_prev_frame (frame
);
1133 gdb_assert (frame
!= NULL
);
1136 func_addr
= get_frame_func (frame
);
1137 gdbarch
= get_frame_arch (frame
);
1138 caller_frame
= get_prev_frame (frame
);
1139 if (gdbarch
!= frame_unwind_arch (frame
))
1141 struct bound_minimal_symbol msym
1142 = lookup_minimal_symbol_by_pc (func_addr
);
1143 struct gdbarch
*caller_gdbarch
= frame_unwind_arch (frame
);
1145 throw_error (NO_ENTRY_VALUE_ERROR
,
1146 _("DW_OP_GNU_entry_value resolving callee gdbarch %s "
1147 "(of %s (%s)) does not match caller gdbarch %s"),
1148 gdbarch_bfd_arch_info (gdbarch
)->printable_name
,
1149 paddress (gdbarch
, func_addr
),
1150 (msym
.minsym
== NULL
? "???"
1151 : MSYMBOL_PRINT_NAME (msym
.minsym
)),
1152 gdbarch_bfd_arch_info (caller_gdbarch
)->printable_name
);
1155 if (caller_frame
== NULL
)
1157 struct bound_minimal_symbol msym
1158 = lookup_minimal_symbol_by_pc (func_addr
);
1160 throw_error (NO_ENTRY_VALUE_ERROR
, _("DW_OP_GNU_entry_value resolving "
1161 "requires caller of %s (%s)"),
1162 paddress (gdbarch
, func_addr
),
1163 (msym
.minsym
== NULL
? "???"
1164 : MSYMBOL_PRINT_NAME (msym
.minsym
)));
1166 caller_pc
= get_frame_pc (caller_frame
);
1167 call_site
= call_site_for_pc (gdbarch
, caller_pc
);
1169 target_addr
= call_site_to_target_addr (gdbarch
, call_site
, caller_frame
);
1170 if (target_addr
!= func_addr
)
1172 struct minimal_symbol
*target_msym
, *func_msym
;
1174 target_msym
= lookup_minimal_symbol_by_pc (target_addr
).minsym
;
1175 func_msym
= lookup_minimal_symbol_by_pc (func_addr
).minsym
;
1176 throw_error (NO_ENTRY_VALUE_ERROR
,
1177 _("DW_OP_GNU_entry_value resolving expects callee %s at %s "
1178 "but the called frame is for %s at %s"),
1179 (target_msym
== NULL
? "???"
1180 : MSYMBOL_PRINT_NAME (target_msym
)),
1181 paddress (gdbarch
, target_addr
),
1182 func_msym
== NULL
? "???" : MSYMBOL_PRINT_NAME (func_msym
),
1183 paddress (gdbarch
, func_addr
));
1186 /* No entry value based parameters would be reliable if this function can
1187 call itself via tail calls. */
1188 func_verify_no_selftailcall (gdbarch
, func_addr
);
1190 for (iparams
= 0; iparams
< call_site
->parameter_count
; iparams
++)
1192 parameter
= &call_site
->parameter
[iparams
];
1193 if (call_site_parameter_matches (parameter
, kind
, kind_u
))
1196 if (iparams
== call_site
->parameter_count
)
1198 struct minimal_symbol
*msym
1199 = lookup_minimal_symbol_by_pc (caller_pc
).minsym
;
1201 /* DW_TAG_GNU_call_site_parameter will be missing just if GCC could not
1202 determine its value. */
1203 throw_error (NO_ENTRY_VALUE_ERROR
, _("Cannot find matching parameter "
1204 "at DW_TAG_GNU_call_site %s at %s"),
1205 paddress (gdbarch
, caller_pc
),
1206 msym
== NULL
? "???" : MSYMBOL_PRINT_NAME (msym
));
1209 *per_cu_return
= call_site
->per_cu
;
1213 /* Return value for PARAMETER matching DEREF_SIZE. If DEREF_SIZE is -1, return
1214 the normal DW_AT_GNU_call_site_value block. Otherwise return the
1215 DW_AT_GNU_call_site_data_value (dereferenced) block.
1217 TYPE and CALLER_FRAME specify how to evaluate the DWARF block into returned
1220 Function always returns non-NULL, non-optimized out value. It throws
1221 NO_ENTRY_VALUE_ERROR if it cannot resolve the value for any reason. */
1223 static struct value
*
1224 dwarf_entry_parameter_to_value (struct call_site_parameter
*parameter
,
1225 CORE_ADDR deref_size
, struct type
*type
,
1226 struct frame_info
*caller_frame
,
1227 struct dwarf2_per_cu_data
*per_cu
)
1229 const gdb_byte
*data_src
;
1233 data_src
= deref_size
== -1 ? parameter
->value
: parameter
->data_value
;
1234 size
= deref_size
== -1 ? parameter
->value_size
: parameter
->data_value_size
;
1236 /* DEREF_SIZE size is not verified here. */
1237 if (data_src
== NULL
)
1238 throw_error (NO_ENTRY_VALUE_ERROR
,
1239 _("Cannot resolve DW_AT_GNU_call_site_data_value"));
1241 /* DW_AT_GNU_call_site_value is a DWARF expression, not a DWARF
1242 location. Postprocessing of DWARF_VALUE_MEMORY would lose the type from
1244 data
= (gdb_byte
*) alloca (size
+ 1);
1245 memcpy (data
, data_src
, size
);
1246 data
[size
] = DW_OP_stack_value
;
1248 return dwarf2_evaluate_loc_desc (type
, caller_frame
, data
, size
+ 1, per_cu
);
1251 /* Execute DWARF block of call_site_parameter which matches KIND and KIND_U.
1252 Choose DEREF_SIZE value of that parameter. Search caller of the CTX's
1253 frame. CTX must be of dwarf_expr_ctx_funcs kind.
1255 The CTX caller can be from a different CU - per_cu_dwarf_call implementation
1256 can be more simple as it does not support cross-CU DWARF executions. */
1259 dwarf_expr_push_dwarf_reg_entry_value (struct dwarf_expr_context
*ctx
,
1260 enum call_site_parameter_kind kind
,
1261 union call_site_parameter_u kind_u
,
1264 struct dwarf_expr_baton
*debaton
;
1265 struct frame_info
*frame
, *caller_frame
;
1266 struct dwarf2_per_cu_data
*caller_per_cu
;
1267 struct dwarf_expr_baton baton_local
;
1268 struct dwarf_expr_context saved_ctx
;
1269 struct call_site_parameter
*parameter
;
1270 const gdb_byte
*data_src
;
1273 gdb_assert (ctx
->funcs
== &dwarf_expr_ctx_funcs
);
1274 debaton
= (struct dwarf_expr_baton
*) ctx
->baton
;
1275 frame
= debaton
->frame
;
1276 caller_frame
= get_prev_frame (frame
);
1278 parameter
= dwarf_expr_reg_to_entry_parameter (frame
, kind
, kind_u
,
1280 data_src
= deref_size
== -1 ? parameter
->value
: parameter
->data_value
;
1281 size
= deref_size
== -1 ? parameter
->value_size
: parameter
->data_value_size
;
1283 /* DEREF_SIZE size is not verified here. */
1284 if (data_src
== NULL
)
1285 throw_error (NO_ENTRY_VALUE_ERROR
,
1286 _("Cannot resolve DW_AT_GNU_call_site_data_value"));
1288 baton_local
.frame
= caller_frame
;
1289 baton_local
.per_cu
= caller_per_cu
;
1290 baton_local
.obj_address
= 0;
1292 saved_ctx
.gdbarch
= ctx
->gdbarch
;
1293 saved_ctx
.addr_size
= ctx
->addr_size
;
1294 saved_ctx
.offset
= ctx
->offset
;
1295 saved_ctx
.baton
= ctx
->baton
;
1296 ctx
->gdbarch
= get_objfile_arch (dwarf2_per_cu_objfile (baton_local
.per_cu
));
1297 ctx
->addr_size
= dwarf2_per_cu_addr_size (baton_local
.per_cu
);
1298 ctx
->offset
= dwarf2_per_cu_text_offset (baton_local
.per_cu
);
1299 ctx
->baton
= &baton_local
;
1301 dwarf_expr_eval (ctx
, data_src
, size
);
1303 ctx
->gdbarch
= saved_ctx
.gdbarch
;
1304 ctx
->addr_size
= saved_ctx
.addr_size
;
1305 ctx
->offset
= saved_ctx
.offset
;
1306 ctx
->baton
= saved_ctx
.baton
;
1309 /* Callback function for dwarf2_evaluate_loc_desc.
1310 Fetch the address indexed by DW_OP_GNU_addr_index. */
1313 dwarf_expr_get_addr_index (void *baton
, unsigned int index
)
1315 struct dwarf_expr_baton
*debaton
= (struct dwarf_expr_baton
*) baton
;
1317 return dwarf2_read_addr_index (debaton
->per_cu
, index
);
1320 /* Callback function for get_object_address. Return the address of the VLA
1324 dwarf_expr_get_obj_addr (void *baton
)
1326 struct dwarf_expr_baton
*debaton
= (struct dwarf_expr_baton
*) baton
;
1328 gdb_assert (debaton
!= NULL
);
1330 if (debaton
->obj_address
== 0)
1331 error (_("Location address is not set."));
1333 return debaton
->obj_address
;
1336 /* VALUE must be of type lval_computed with entry_data_value_funcs. Perform
1337 the indirect method on it, that is use its stored target value, the sole
1338 purpose of entry_data_value_funcs.. */
1340 static struct value
*
1341 entry_data_value_coerce_ref (const struct value
*value
)
1343 struct type
*checked_type
= check_typedef (value_type (value
));
1344 struct value
*target_val
;
1346 if (TYPE_CODE (checked_type
) != TYPE_CODE_REF
)
1349 target_val
= (struct value
*) value_computed_closure (value
);
1350 value_incref (target_val
);
1354 /* Implement copy_closure. */
1357 entry_data_value_copy_closure (const struct value
*v
)
1359 struct value
*target_val
= (struct value
*) value_computed_closure (v
);
1361 value_incref (target_val
);
1365 /* Implement free_closure. */
1368 entry_data_value_free_closure (struct value
*v
)
1370 struct value
*target_val
= (struct value
*) value_computed_closure (v
);
1372 value_free (target_val
);
1375 /* Vector for methods for an entry value reference where the referenced value
1376 is stored in the caller. On the first dereference use
1377 DW_AT_GNU_call_site_data_value in the caller. */
1379 static const struct lval_funcs entry_data_value_funcs
=
1383 NULL
, /* indirect */
1384 entry_data_value_coerce_ref
,
1385 NULL
, /* check_synthetic_pointer */
1386 entry_data_value_copy_closure
,
1387 entry_data_value_free_closure
1390 /* Read parameter of TYPE at (callee) FRAME's function entry. KIND and KIND_U
1391 are used to match DW_AT_location at the caller's
1392 DW_TAG_GNU_call_site_parameter.
1394 Function always returns non-NULL value. It throws NO_ENTRY_VALUE_ERROR if it
1395 cannot resolve the parameter for any reason. */
1397 static struct value
*
1398 value_of_dwarf_reg_entry (struct type
*type
, struct frame_info
*frame
,
1399 enum call_site_parameter_kind kind
,
1400 union call_site_parameter_u kind_u
)
1402 struct type
*checked_type
= check_typedef (type
);
1403 struct type
*target_type
= TYPE_TARGET_TYPE (checked_type
);
1404 struct frame_info
*caller_frame
= get_prev_frame (frame
);
1405 struct value
*outer_val
, *target_val
, *val
;
1406 struct call_site_parameter
*parameter
;
1407 struct dwarf2_per_cu_data
*caller_per_cu
;
1409 parameter
= dwarf_expr_reg_to_entry_parameter (frame
, kind
, kind_u
,
1412 outer_val
= dwarf_entry_parameter_to_value (parameter
, -1 /* deref_size */,
1416 /* Check if DW_AT_GNU_call_site_data_value cannot be used. If it should be
1417 used and it is not available do not fall back to OUTER_VAL - dereferencing
1418 TYPE_CODE_REF with non-entry data value would give current value - not the
1421 if (TYPE_CODE (checked_type
) != TYPE_CODE_REF
1422 || TYPE_TARGET_TYPE (checked_type
) == NULL
)
1425 target_val
= dwarf_entry_parameter_to_value (parameter
,
1426 TYPE_LENGTH (target_type
),
1427 target_type
, caller_frame
,
1430 release_value (target_val
);
1431 val
= allocate_computed_value (type
, &entry_data_value_funcs
,
1432 target_val
/* closure */);
1434 /* Copy the referencing pointer to the new computed value. */
1435 memcpy (value_contents_raw (val
), value_contents_raw (outer_val
),
1436 TYPE_LENGTH (checked_type
));
1437 set_value_lazy (val
, 0);
1442 /* Read parameter of TYPE at (callee) FRAME's function entry. DATA and
1443 SIZE are DWARF block used to match DW_AT_location at the caller's
1444 DW_TAG_GNU_call_site_parameter.
1446 Function always returns non-NULL value. It throws NO_ENTRY_VALUE_ERROR if it
1447 cannot resolve the parameter for any reason. */
1449 static struct value
*
1450 value_of_dwarf_block_entry (struct type
*type
, struct frame_info
*frame
,
1451 const gdb_byte
*block
, size_t block_len
)
1453 union call_site_parameter_u kind_u
;
1455 kind_u
.dwarf_reg
= dwarf_block_to_dwarf_reg (block
, block
+ block_len
);
1456 if (kind_u
.dwarf_reg
!= -1)
1457 return value_of_dwarf_reg_entry (type
, frame
, CALL_SITE_PARAMETER_DWARF_REG
,
1460 if (dwarf_block_to_fb_offset (block
, block
+ block_len
, &kind_u
.fb_offset
))
1461 return value_of_dwarf_reg_entry (type
, frame
, CALL_SITE_PARAMETER_FB_OFFSET
,
1464 /* This can normally happen - throw NO_ENTRY_VALUE_ERROR to get the message
1465 suppressed during normal operation. The expression can be arbitrary if
1466 there is no caller-callee entry value binding expected. */
1467 throw_error (NO_ENTRY_VALUE_ERROR
,
1468 _("DWARF-2 expression error: DW_OP_GNU_entry_value is supported "
1469 "only for single DW_OP_reg* or for DW_OP_fbreg(*)"));
1472 struct piece_closure
1474 /* Reference count. */
1477 /* The CU from which this closure's expression came. */
1478 struct dwarf2_per_cu_data
*per_cu
;
1480 /* The number of pieces used to describe this variable. */
1483 /* The target address size, used only for DWARF_VALUE_STACK. */
1486 /* The pieces themselves. */
1487 struct dwarf_expr_piece
*pieces
;
1490 /* Allocate a closure for a value formed from separately-described
1493 static struct piece_closure
*
1494 allocate_piece_closure (struct dwarf2_per_cu_data
*per_cu
,
1495 int n_pieces
, struct dwarf_expr_piece
*pieces
,
1498 struct piece_closure
*c
= XCNEW (struct piece_closure
);
1503 c
->n_pieces
= n_pieces
;
1504 c
->addr_size
= addr_size
;
1505 c
->pieces
= XCNEWVEC (struct dwarf_expr_piece
, n_pieces
);
1507 memcpy (c
->pieces
, pieces
, n_pieces
* sizeof (struct dwarf_expr_piece
));
1508 for (i
= 0; i
< n_pieces
; ++i
)
1509 if (c
->pieces
[i
].location
== DWARF_VALUE_STACK
)
1510 value_incref (c
->pieces
[i
].v
.value
);
1515 /* The lowest-level function to extract bits from a byte buffer.
1516 SOURCE is the buffer. It is updated if we read to the end of a
1518 SOURCE_OFFSET_BITS is the offset of the first bit to read. It is
1519 updated to reflect the number of bits actually read.
1520 NBITS is the number of bits we want to read. It is updated to
1521 reflect the number of bits actually read. This function may read
1523 BITS_BIG_ENDIAN is taken directly from gdbarch.
1524 This function returns the extracted bits. */
1527 extract_bits_primitive (const gdb_byte
**source
,
1528 unsigned int *source_offset_bits
,
1529 int *nbits
, int bits_big_endian
)
1531 unsigned int avail
, mask
, datum
;
1533 gdb_assert (*source_offset_bits
< 8);
1535 avail
= 8 - *source_offset_bits
;
1539 mask
= (1 << avail
) - 1;
1541 if (bits_big_endian
)
1542 datum
>>= 8 - (*source_offset_bits
+ *nbits
);
1544 datum
>>= *source_offset_bits
;
1548 *source_offset_bits
+= avail
;
1549 if (*source_offset_bits
>= 8)
1551 *source_offset_bits
-= 8;
1558 /* Extract some bits from a source buffer and move forward in the
1561 SOURCE is the source buffer. It is updated as bytes are read.
1562 SOURCE_OFFSET_BITS is the offset into SOURCE. It is updated as
1564 NBITS is the number of bits to read.
1565 BITS_BIG_ENDIAN is taken directly from gdbarch.
1567 This function returns the bits that were read. */
1570 extract_bits (const gdb_byte
**source
, unsigned int *source_offset_bits
,
1571 int nbits
, int bits_big_endian
)
1575 gdb_assert (nbits
> 0 && nbits
<= 8);
1577 datum
= extract_bits_primitive (source
, source_offset_bits
, &nbits
,
1583 more
= extract_bits_primitive (source
, source_offset_bits
, &nbits
,
1585 if (bits_big_endian
)
1595 /* Write some bits into a buffer and move forward in the buffer.
1597 DATUM is the bits to write. The low-order bits of DATUM are used.
1598 DEST is the destination buffer. It is updated as bytes are
1600 DEST_OFFSET_BITS is the bit offset in DEST at which writing is
1602 NBITS is the number of valid bits in DATUM.
1603 BITS_BIG_ENDIAN is taken directly from gdbarch. */
1606 insert_bits (unsigned int datum
,
1607 gdb_byte
*dest
, unsigned int dest_offset_bits
,
1608 int nbits
, int bits_big_endian
)
1612 gdb_assert (dest_offset_bits
+ nbits
<= 8);
1614 mask
= (1 << nbits
) - 1;
1615 if (bits_big_endian
)
1617 datum
<<= 8 - (dest_offset_bits
+ nbits
);
1618 mask
<<= 8 - (dest_offset_bits
+ nbits
);
1622 datum
<<= dest_offset_bits
;
1623 mask
<<= dest_offset_bits
;
1626 gdb_assert ((datum
& ~mask
) == 0);
1628 *dest
= (*dest
& ~mask
) | datum
;
1631 /* Copy bits from a source to a destination.
1633 DEST is where the bits should be written.
1634 DEST_OFFSET_BITS is the bit offset into DEST.
1635 SOURCE is the source of bits.
1636 SOURCE_OFFSET_BITS is the bit offset into SOURCE.
1637 BIT_COUNT is the number of bits to copy.
1638 BITS_BIG_ENDIAN is taken directly from gdbarch. */
1641 copy_bitwise (gdb_byte
*dest
, unsigned int dest_offset_bits
,
1642 const gdb_byte
*source
, unsigned int source_offset_bits
,
1643 unsigned int bit_count
,
1644 int bits_big_endian
)
1646 unsigned int dest_avail
;
1649 /* Reduce everything to byte-size pieces. */
1650 dest
+= dest_offset_bits
/ 8;
1651 dest_offset_bits
%= 8;
1652 source
+= source_offset_bits
/ 8;
1653 source_offset_bits
%= 8;
1655 dest_avail
= 8 - dest_offset_bits
% 8;
1657 /* See if we can fill the first destination byte. */
1658 if (dest_avail
< bit_count
)
1660 datum
= extract_bits (&source
, &source_offset_bits
, dest_avail
,
1662 insert_bits (datum
, dest
, dest_offset_bits
, dest_avail
, bits_big_endian
);
1664 dest_offset_bits
= 0;
1665 bit_count
-= dest_avail
;
1668 /* Now, either DEST_OFFSET_BITS is byte-aligned, or we have fewer
1669 than 8 bits remaining. */
1670 gdb_assert (dest_offset_bits
% 8 == 0 || bit_count
< 8);
1671 for (; bit_count
>= 8; bit_count
-= 8)
1673 datum
= extract_bits (&source
, &source_offset_bits
, 8, bits_big_endian
);
1674 *dest
++ = (gdb_byte
) datum
;
1677 /* Finally, we may have a few leftover bits. */
1678 gdb_assert (bit_count
<= 8 - dest_offset_bits
% 8);
1681 datum
= extract_bits (&source
, &source_offset_bits
, bit_count
,
1683 insert_bits (datum
, dest
, dest_offset_bits
, bit_count
, bits_big_endian
);
1688 read_pieced_value (struct value
*v
)
1692 ULONGEST bits_to_skip
;
1694 struct piece_closure
*c
1695 = (struct piece_closure
*) value_computed_closure (v
);
1696 struct frame_info
*frame
= frame_find_by_id (VALUE_FRAME_ID (v
));
1698 size_t buffer_size
= 0;
1699 gdb_byte
*buffer
= NULL
;
1700 struct cleanup
*cleanup
;
1702 = gdbarch_bits_big_endian (get_type_arch (value_type (v
)));
1704 if (value_type (v
) != value_enclosing_type (v
))
1705 internal_error (__FILE__
, __LINE__
,
1706 _("Should not be able to create a lazy value with "
1707 "an enclosing type"));
1709 cleanup
= make_cleanup (free_current_contents
, &buffer
);
1711 contents
= value_contents_raw (v
);
1712 bits_to_skip
= 8 * value_offset (v
);
1713 if (value_bitsize (v
))
1715 bits_to_skip
+= value_bitpos (v
);
1716 type_len
= value_bitsize (v
);
1719 type_len
= 8 * TYPE_LENGTH (value_type (v
));
1721 for (i
= 0; i
< c
->n_pieces
&& offset
< type_len
; i
++)
1723 struct dwarf_expr_piece
*p
= &c
->pieces
[i
];
1724 size_t this_size
, this_size_bits
;
1725 long dest_offset_bits
, source_offset_bits
, source_offset
;
1726 const gdb_byte
*intermediate_buffer
;
1728 /* Compute size, source, and destination offsets for copying, in
1730 this_size_bits
= p
->size
;
1731 if (bits_to_skip
> 0 && bits_to_skip
>= this_size_bits
)
1733 bits_to_skip
-= this_size_bits
;
1736 if (bits_to_skip
> 0)
1738 dest_offset_bits
= 0;
1739 source_offset_bits
= bits_to_skip
;
1740 this_size_bits
-= bits_to_skip
;
1745 dest_offset_bits
= offset
;
1746 source_offset_bits
= 0;
1748 if (this_size_bits
> type_len
- offset
)
1749 this_size_bits
= type_len
- offset
;
1751 this_size
= (this_size_bits
+ source_offset_bits
% 8 + 7) / 8;
1752 source_offset
= source_offset_bits
/ 8;
1753 if (buffer_size
< this_size
)
1755 buffer_size
= this_size
;
1756 buffer
= (gdb_byte
*) xrealloc (buffer
, buffer_size
);
1758 intermediate_buffer
= buffer
;
1760 /* Copy from the source to DEST_BUFFER. */
1761 switch (p
->location
)
1763 case DWARF_VALUE_REGISTER
:
1765 struct gdbarch
*arch
= get_frame_arch (frame
);
1766 int gdb_regnum
= dwarf_reg_to_regnum_or_error (arch
, p
->v
.regno
);
1768 int reg_offset
= source_offset
;
1770 if (gdbarch_byte_order (arch
) == BFD_ENDIAN_BIG
1771 && this_size
< register_size (arch
, gdb_regnum
))
1773 /* Big-endian, and we want less than full size. */
1774 reg_offset
= register_size (arch
, gdb_regnum
) - this_size
;
1775 /* We want the lower-order THIS_SIZE_BITS of the bytes
1776 we extract from the register. */
1777 source_offset_bits
+= 8 * this_size
- this_size_bits
;
1780 if (!get_frame_register_bytes (frame
, gdb_regnum
, reg_offset
,
1784 /* Just so garbage doesn't ever shine through. */
1785 memset (buffer
, 0, this_size
);
1788 mark_value_bits_optimized_out (v
, offset
, this_size_bits
);
1790 mark_value_bits_unavailable (v
, offset
, this_size_bits
);
1795 case DWARF_VALUE_MEMORY
:
1796 read_value_memory (v
, offset
,
1797 p
->v
.mem
.in_stack_memory
,
1798 p
->v
.mem
.addr
+ source_offset
,
1802 case DWARF_VALUE_STACK
:
1804 size_t n
= this_size
;
1806 if (n
> c
->addr_size
- source_offset
)
1807 n
= (c
->addr_size
>= source_offset
1808 ? c
->addr_size
- source_offset
1816 const gdb_byte
*val_bytes
= value_contents_all (p
->v
.value
);
1818 intermediate_buffer
= val_bytes
+ source_offset
;
1823 case DWARF_VALUE_LITERAL
:
1825 size_t n
= this_size
;
1827 if (n
> p
->v
.literal
.length
- source_offset
)
1828 n
= (p
->v
.literal
.length
>= source_offset
1829 ? p
->v
.literal
.length
- source_offset
1832 intermediate_buffer
= p
->v
.literal
.data
+ source_offset
;
1836 /* These bits show up as zeros -- but do not cause the value
1837 to be considered optimized-out. */
1838 case DWARF_VALUE_IMPLICIT_POINTER
:
1841 case DWARF_VALUE_OPTIMIZED_OUT
:
1842 mark_value_bits_optimized_out (v
, offset
, this_size_bits
);
1846 internal_error (__FILE__
, __LINE__
, _("invalid location type"));
1849 if (p
->location
!= DWARF_VALUE_OPTIMIZED_OUT
1850 && p
->location
!= DWARF_VALUE_IMPLICIT_POINTER
)
1851 copy_bitwise (contents
, dest_offset_bits
,
1852 intermediate_buffer
, source_offset_bits
% 8,
1853 this_size_bits
, bits_big_endian
);
1855 offset
+= this_size_bits
;
1858 do_cleanups (cleanup
);
1862 write_pieced_value (struct value
*to
, struct value
*from
)
1866 ULONGEST bits_to_skip
;
1867 const gdb_byte
*contents
;
1868 struct piece_closure
*c
1869 = (struct piece_closure
*) value_computed_closure (to
);
1870 struct frame_info
*frame
= frame_find_by_id (VALUE_FRAME_ID (to
));
1872 size_t buffer_size
= 0;
1873 gdb_byte
*buffer
= NULL
;
1874 struct cleanup
*cleanup
;
1876 = gdbarch_bits_big_endian (get_type_arch (value_type (to
)));
1880 mark_value_bytes_optimized_out (to
, 0, TYPE_LENGTH (value_type (to
)));
1884 cleanup
= make_cleanup (free_current_contents
, &buffer
);
1886 contents
= value_contents (from
);
1887 bits_to_skip
= 8 * value_offset (to
);
1888 if (value_bitsize (to
))
1890 bits_to_skip
+= value_bitpos (to
);
1891 type_len
= value_bitsize (to
);
1894 type_len
= 8 * TYPE_LENGTH (value_type (to
));
1896 for (i
= 0; i
< c
->n_pieces
&& offset
< type_len
; i
++)
1898 struct dwarf_expr_piece
*p
= &c
->pieces
[i
];
1899 size_t this_size_bits
, this_size
;
1900 long dest_offset_bits
, source_offset_bits
, dest_offset
, source_offset
;
1902 const gdb_byte
*source_buffer
;
1904 this_size_bits
= p
->size
;
1905 if (bits_to_skip
> 0 && bits_to_skip
>= this_size_bits
)
1907 bits_to_skip
-= this_size_bits
;
1910 if (this_size_bits
> type_len
- offset
)
1911 this_size_bits
= type_len
- offset
;
1912 if (bits_to_skip
> 0)
1914 dest_offset_bits
= bits_to_skip
;
1915 source_offset_bits
= 0;
1916 this_size_bits
-= bits_to_skip
;
1921 dest_offset_bits
= 0;
1922 source_offset_bits
= offset
;
1925 this_size
= (this_size_bits
+ source_offset_bits
% 8 + 7) / 8;
1926 source_offset
= source_offset_bits
/ 8;
1927 dest_offset
= dest_offset_bits
/ 8;
1928 if (dest_offset_bits
% 8 == 0 && source_offset_bits
% 8 == 0)
1930 source_buffer
= contents
+ source_offset
;
1935 if (buffer_size
< this_size
)
1937 buffer_size
= this_size
;
1938 buffer
= (gdb_byte
*) xrealloc (buffer
, buffer_size
);
1940 source_buffer
= buffer
;
1944 switch (p
->location
)
1946 case DWARF_VALUE_REGISTER
:
1948 struct gdbarch
*arch
= get_frame_arch (frame
);
1949 int gdb_regnum
= dwarf_reg_to_regnum_or_error (arch
, p
->v
.regno
);
1950 int reg_offset
= dest_offset
;
1952 if (gdbarch_byte_order (arch
) == BFD_ENDIAN_BIG
1953 && this_size
<= register_size (arch
, gdb_regnum
))
1955 /* Big-endian, and we want less than full size. */
1956 reg_offset
= register_size (arch
, gdb_regnum
) - this_size
;
1963 if (!get_frame_register_bytes (frame
, gdb_regnum
, reg_offset
,
1968 throw_error (OPTIMIZED_OUT_ERROR
,
1969 _("Can't do read-modify-write to "
1970 "update bitfield; containing word "
1971 "has been optimized out"));
1973 throw_error (NOT_AVAILABLE_ERROR
,
1974 _("Can't do read-modify-write to update "
1975 "bitfield; containing word "
1978 copy_bitwise (buffer
, dest_offset_bits
,
1979 contents
, source_offset_bits
,
1984 put_frame_register_bytes (frame
, gdb_regnum
, reg_offset
,
1985 this_size
, source_buffer
);
1988 case DWARF_VALUE_MEMORY
:
1991 /* Only the first and last bytes can possibly have any
1993 read_memory (p
->v
.mem
.addr
+ dest_offset
, buffer
, 1);
1994 read_memory (p
->v
.mem
.addr
+ dest_offset
+ this_size
- 1,
1995 buffer
+ this_size
- 1, 1);
1996 copy_bitwise (buffer
, dest_offset_bits
,
1997 contents
, source_offset_bits
,
2002 write_memory (p
->v
.mem
.addr
+ dest_offset
,
2003 source_buffer
, this_size
);
2006 mark_value_bytes_optimized_out (to
, 0, TYPE_LENGTH (value_type (to
)));
2009 offset
+= this_size_bits
;
2012 do_cleanups (cleanup
);
2015 /* An implementation of an lval_funcs method to see whether a value is
2016 a synthetic pointer. */
2019 check_pieced_synthetic_pointer (const struct value
*value
, int bit_offset
,
2022 struct piece_closure
*c
2023 = (struct piece_closure
*) value_computed_closure (value
);
2026 bit_offset
+= 8 * value_offset (value
);
2027 if (value_bitsize (value
))
2028 bit_offset
+= value_bitpos (value
);
2030 for (i
= 0; i
< c
->n_pieces
&& bit_length
> 0; i
++)
2032 struct dwarf_expr_piece
*p
= &c
->pieces
[i
];
2033 size_t this_size_bits
= p
->size
;
2037 if (bit_offset
>= this_size_bits
)
2039 bit_offset
-= this_size_bits
;
2043 bit_length
-= this_size_bits
- bit_offset
;
2047 bit_length
-= this_size_bits
;
2049 if (p
->location
!= DWARF_VALUE_IMPLICIT_POINTER
)
2056 /* A wrapper function for get_frame_address_in_block. */
2059 get_frame_address_in_block_wrapper (void *baton
)
2061 return get_frame_address_in_block ((struct frame_info
*) baton
);
2064 /* Fetch a DW_AT_const_value through a synthetic pointer. */
2066 static struct value
*
2067 fetch_const_value_from_synthetic_pointer (sect_offset die
, LONGEST byte_offset
,
2068 struct dwarf2_per_cu_data
*per_cu
,
2071 struct value
*result
= NULL
;
2072 struct obstack temp_obstack
;
2073 struct cleanup
*cleanup
;
2074 const gdb_byte
*bytes
;
2077 obstack_init (&temp_obstack
);
2078 cleanup
= make_cleanup_obstack_free (&temp_obstack
);
2079 bytes
= dwarf2_fetch_constant_bytes (die
, per_cu
, &temp_obstack
, &len
);
2083 if (byte_offset
>= 0
2084 && byte_offset
+ TYPE_LENGTH (TYPE_TARGET_TYPE (type
)) <= len
)
2086 bytes
+= byte_offset
;
2087 result
= value_from_contents (TYPE_TARGET_TYPE (type
), bytes
);
2090 invalid_synthetic_pointer ();
2093 result
= allocate_optimized_out_value (TYPE_TARGET_TYPE (type
));
2095 do_cleanups (cleanup
);
2100 /* Fetch the value pointed to by a synthetic pointer. */
2102 static struct value
*
2103 indirect_synthetic_pointer (sect_offset die
, LONGEST byte_offset
,
2104 struct dwarf2_per_cu_data
*per_cu
,
2105 struct frame_info
*frame
, struct type
*type
)
2107 /* Fetch the location expression of the DIE we're pointing to. */
2108 struct dwarf2_locexpr_baton baton
2109 = dwarf2_fetch_die_loc_sect_off (die
, per_cu
,
2110 get_frame_address_in_block_wrapper
, frame
);
2112 /* If pointed-to DIE has a DW_AT_location, evaluate it and return the
2113 resulting value. Otherwise, it may have a DW_AT_const_value instead,
2114 or it may've been optimized out. */
2115 if (baton
.data
!= NULL
)
2116 return dwarf2_evaluate_loc_desc_full (TYPE_TARGET_TYPE (type
), frame
,
2117 baton
.data
, baton
.size
, baton
.per_cu
,
2120 return fetch_const_value_from_synthetic_pointer (die
, byte_offset
, per_cu
,
2124 /* An implementation of an lval_funcs method to indirect through a
2125 pointer. This handles the synthetic pointer case when needed. */
2127 static struct value
*
2128 indirect_pieced_value (struct value
*value
)
2130 struct piece_closure
*c
2131 = (struct piece_closure
*) value_computed_closure (value
);
2133 struct frame_info
*frame
;
2134 struct dwarf2_locexpr_baton baton
;
2135 int i
, bit_offset
, bit_length
;
2136 struct dwarf_expr_piece
*piece
= NULL
;
2137 LONGEST byte_offset
;
2138 enum bfd_endian byte_order
;
2140 type
= check_typedef (value_type (value
));
2141 if (TYPE_CODE (type
) != TYPE_CODE_PTR
)
2144 bit_length
= 8 * TYPE_LENGTH (type
);
2145 bit_offset
= 8 * value_offset (value
);
2146 if (value_bitsize (value
))
2147 bit_offset
+= value_bitpos (value
);
2149 for (i
= 0; i
< c
->n_pieces
&& bit_length
> 0; i
++)
2151 struct dwarf_expr_piece
*p
= &c
->pieces
[i
];
2152 size_t this_size_bits
= p
->size
;
2156 if (bit_offset
>= this_size_bits
)
2158 bit_offset
-= this_size_bits
;
2162 bit_length
-= this_size_bits
- bit_offset
;
2166 bit_length
-= this_size_bits
;
2168 if (p
->location
!= DWARF_VALUE_IMPLICIT_POINTER
)
2171 if (bit_length
!= 0)
2172 error (_("Invalid use of DW_OP_GNU_implicit_pointer"));
2178 gdb_assert (piece
!= NULL
);
2179 frame
= get_selected_frame (_("No frame selected."));
2181 /* This is an offset requested by GDB, such as value subscripts.
2182 However, due to how synthetic pointers are implemented, this is
2183 always presented to us as a pointer type. This means we have to
2184 sign-extend it manually as appropriate. Use raw
2185 extract_signed_integer directly rather than value_as_address and
2186 sign extend afterwards on architectures that would need it
2187 (mostly everywhere except MIPS, which has signed addresses) as
2188 the later would go through gdbarch_pointer_to_address and thus
2189 return a CORE_ADDR with high bits set on architectures that
2190 encode address spaces and other things in CORE_ADDR. */
2191 byte_order
= gdbarch_byte_order (get_frame_arch (frame
));
2192 byte_offset
= extract_signed_integer (value_contents (value
),
2193 TYPE_LENGTH (type
), byte_order
);
2194 byte_offset
+= piece
->v
.ptr
.offset
;
2196 return indirect_synthetic_pointer (piece
->v
.ptr
.die
, byte_offset
, c
->per_cu
,
2200 /* Implementation of the coerce_ref method of lval_funcs for synthetic C++
2203 static struct value
*
2204 coerce_pieced_ref (const struct value
*value
)
2206 struct type
*type
= check_typedef (value_type (value
));
2208 if (value_bits_synthetic_pointer (value
, value_embedded_offset (value
),
2209 TARGET_CHAR_BIT
* TYPE_LENGTH (type
)))
2211 const struct piece_closure
*closure
2212 = (struct piece_closure
*) value_computed_closure (value
);
2213 struct frame_info
*frame
2214 = get_selected_frame (_("No frame selected."));
2216 /* gdb represents synthetic pointers as pieced values with a single
2218 gdb_assert (closure
!= NULL
);
2219 gdb_assert (closure
->n_pieces
== 1);
2221 return indirect_synthetic_pointer (closure
->pieces
->v
.ptr
.die
,
2222 closure
->pieces
->v
.ptr
.offset
,
2223 closure
->per_cu
, frame
, type
);
2227 /* Else: not a synthetic reference; do nothing. */
2233 copy_pieced_value_closure (const struct value
*v
)
2235 struct piece_closure
*c
2236 = (struct piece_closure
*) value_computed_closure (v
);
2243 free_pieced_value_closure (struct value
*v
)
2245 struct piece_closure
*c
2246 = (struct piece_closure
*) value_computed_closure (v
);
2253 for (i
= 0; i
< c
->n_pieces
; ++i
)
2254 if (c
->pieces
[i
].location
== DWARF_VALUE_STACK
)
2255 value_free (c
->pieces
[i
].v
.value
);
2262 /* Functions for accessing a variable described by DW_OP_piece. */
2263 static const struct lval_funcs pieced_value_funcs
= {
2266 indirect_pieced_value
,
2268 check_pieced_synthetic_pointer
,
2269 copy_pieced_value_closure
,
2270 free_pieced_value_closure
2273 /* Virtual method table for dwarf2_evaluate_loc_desc_full below. */
2275 const struct dwarf_expr_context_funcs dwarf_expr_ctx_funcs
=
2277 dwarf_expr_read_addr_from_reg
,
2278 dwarf_expr_get_reg_value
,
2279 dwarf_expr_read_mem
,
2280 dwarf_expr_frame_base
,
2281 dwarf_expr_frame_cfa
,
2282 dwarf_expr_frame_pc
,
2283 dwarf_expr_tls_address
,
2284 dwarf_expr_dwarf_call
,
2285 dwarf_expr_get_base_type
,
2286 dwarf_expr_push_dwarf_reg_entry_value
,
2287 dwarf_expr_get_addr_index
,
2288 dwarf_expr_get_obj_addr
2291 /* Evaluate a location description, starting at DATA and with length
2292 SIZE, to find the current location of variable of TYPE in the
2293 context of FRAME. BYTE_OFFSET is applied after the contents are
2296 static struct value
*
2297 dwarf2_evaluate_loc_desc_full (struct type
*type
, struct frame_info
*frame
,
2298 const gdb_byte
*data
, size_t size
,
2299 struct dwarf2_per_cu_data
*per_cu
,
2300 LONGEST byte_offset
)
2302 struct value
*retval
;
2303 struct dwarf_expr_baton baton
;
2304 struct dwarf_expr_context
*ctx
;
2305 struct cleanup
*old_chain
, *value_chain
;
2306 struct objfile
*objfile
= dwarf2_per_cu_objfile (per_cu
);
2308 if (byte_offset
< 0)
2309 invalid_synthetic_pointer ();
2312 return allocate_optimized_out_value (type
);
2314 baton
.frame
= frame
;
2315 baton
.per_cu
= per_cu
;
2316 baton
.obj_address
= 0;
2318 ctx
= new_dwarf_expr_context ();
2319 old_chain
= make_cleanup_free_dwarf_expr_context (ctx
);
2320 value_chain
= make_cleanup_value_free_to_mark (value_mark ());
2322 ctx
->gdbarch
= get_objfile_arch (objfile
);
2323 ctx
->addr_size
= dwarf2_per_cu_addr_size (per_cu
);
2324 ctx
->ref_addr_size
= dwarf2_per_cu_ref_addr_size (per_cu
);
2325 ctx
->offset
= dwarf2_per_cu_text_offset (per_cu
);
2326 ctx
->baton
= &baton
;
2327 ctx
->funcs
= &dwarf_expr_ctx_funcs
;
2331 dwarf_expr_eval (ctx
, data
, size
);
2333 CATCH (ex
, RETURN_MASK_ERROR
)
2335 if (ex
.error
== NOT_AVAILABLE_ERROR
)
2337 do_cleanups (old_chain
);
2338 retval
= allocate_value (type
);
2339 mark_value_bytes_unavailable (retval
, 0, TYPE_LENGTH (type
));
2342 else if (ex
.error
== NO_ENTRY_VALUE_ERROR
)
2344 if (entry_values_debug
)
2345 exception_print (gdb_stdout
, ex
);
2346 do_cleanups (old_chain
);
2347 return allocate_optimized_out_value (type
);
2350 throw_exception (ex
);
2354 if (ctx
->num_pieces
> 0)
2356 struct piece_closure
*c
;
2357 struct frame_id frame_id
= get_frame_id (frame
);
2358 ULONGEST bit_size
= 0;
2361 for (i
= 0; i
< ctx
->num_pieces
; ++i
)
2362 bit_size
+= ctx
->pieces
[i
].size
;
2363 if (8 * (byte_offset
+ TYPE_LENGTH (type
)) > bit_size
)
2364 invalid_synthetic_pointer ();
2366 c
= allocate_piece_closure (per_cu
, ctx
->num_pieces
, ctx
->pieces
,
2368 /* We must clean up the value chain after creating the piece
2369 closure but before allocating the result. */
2370 do_cleanups (value_chain
);
2371 retval
= allocate_computed_value (type
, &pieced_value_funcs
, c
);
2372 VALUE_FRAME_ID (retval
) = frame_id
;
2373 set_value_offset (retval
, byte_offset
);
2377 switch (ctx
->location
)
2379 case DWARF_VALUE_REGISTER
:
2381 struct gdbarch
*arch
= get_frame_arch (frame
);
2383 = longest_to_int (value_as_long (dwarf_expr_fetch (ctx
, 0)));
2384 int gdb_regnum
= dwarf_reg_to_regnum_or_error (arch
, dwarf_regnum
);
2386 if (byte_offset
!= 0)
2387 error (_("cannot use offset on synthetic pointer to register"));
2388 do_cleanups (value_chain
);
2389 retval
= value_from_register (type
, gdb_regnum
, frame
);
2390 if (value_optimized_out (retval
))
2394 /* This means the register has undefined value / was
2395 not saved. As we're computing the location of some
2396 variable etc. in the program, not a value for
2397 inspecting a register ($pc, $sp, etc.), return a
2398 generic optimized out value instead, so that we show
2399 <optimized out> instead of <not saved>. */
2400 do_cleanups (value_chain
);
2401 tmp
= allocate_value (type
);
2402 value_contents_copy (tmp
, 0, retval
, 0, TYPE_LENGTH (type
));
2408 case DWARF_VALUE_MEMORY
:
2410 struct type
*ptr_type
;
2411 CORE_ADDR address
= dwarf_expr_fetch_address (ctx
, 0);
2412 int in_stack_memory
= dwarf_expr_fetch_in_stack_memory (ctx
, 0);
2414 /* DW_OP_deref_size (and possibly other operations too) may
2415 create a pointer instead of an address. Ideally, the
2416 pointer to address conversion would be performed as part
2417 of those operations, but the type of the object to
2418 which the address refers is not known at the time of
2419 the operation. Therefore, we do the conversion here
2420 since the type is readily available. */
2422 switch (TYPE_CODE (type
))
2424 case TYPE_CODE_FUNC
:
2425 case TYPE_CODE_METHOD
:
2426 ptr_type
= builtin_type (ctx
->gdbarch
)->builtin_func_ptr
;
2429 ptr_type
= builtin_type (ctx
->gdbarch
)->builtin_data_ptr
;
2432 address
= value_as_address (value_from_pointer (ptr_type
, address
));
2434 do_cleanups (value_chain
);
2435 retval
= value_at_lazy (type
, address
+ byte_offset
);
2436 if (in_stack_memory
)
2437 set_value_stack (retval
, 1);
2441 case DWARF_VALUE_STACK
:
2443 struct value
*value
= dwarf_expr_fetch (ctx
, 0);
2445 const gdb_byte
*val_bytes
;
2446 size_t n
= TYPE_LENGTH (value_type (value
));
2448 if (byte_offset
+ TYPE_LENGTH (type
) > n
)
2449 invalid_synthetic_pointer ();
2451 val_bytes
= value_contents_all (value
);
2452 val_bytes
+= byte_offset
;
2455 /* Preserve VALUE because we are going to free values back
2456 to the mark, but we still need the value contents
2458 value_incref (value
);
2459 do_cleanups (value_chain
);
2460 make_cleanup_value_free (value
);
2462 retval
= allocate_value (type
);
2463 contents
= value_contents_raw (retval
);
2464 if (n
> TYPE_LENGTH (type
))
2466 struct gdbarch
*objfile_gdbarch
= get_objfile_arch (objfile
);
2468 if (gdbarch_byte_order (objfile_gdbarch
) == BFD_ENDIAN_BIG
)
2469 val_bytes
+= n
- TYPE_LENGTH (type
);
2470 n
= TYPE_LENGTH (type
);
2472 memcpy (contents
, val_bytes
, n
);
2476 case DWARF_VALUE_LITERAL
:
2479 const bfd_byte
*ldata
;
2480 size_t n
= ctx
->len
;
2482 if (byte_offset
+ TYPE_LENGTH (type
) > n
)
2483 invalid_synthetic_pointer ();
2485 do_cleanups (value_chain
);
2486 retval
= allocate_value (type
);
2487 contents
= value_contents_raw (retval
);
2489 ldata
= ctx
->data
+ byte_offset
;
2492 if (n
> TYPE_LENGTH (type
))
2494 struct gdbarch
*objfile_gdbarch
= get_objfile_arch (objfile
);
2496 if (gdbarch_byte_order (objfile_gdbarch
) == BFD_ENDIAN_BIG
)
2497 ldata
+= n
- TYPE_LENGTH (type
);
2498 n
= TYPE_LENGTH (type
);
2500 memcpy (contents
, ldata
, n
);
2504 case DWARF_VALUE_OPTIMIZED_OUT
:
2505 do_cleanups (value_chain
);
2506 retval
= allocate_optimized_out_value (type
);
2509 /* DWARF_VALUE_IMPLICIT_POINTER was converted to a pieced
2510 operation by execute_stack_op. */
2511 case DWARF_VALUE_IMPLICIT_POINTER
:
2512 /* DWARF_VALUE_OPTIMIZED_OUT can't occur in this context --
2513 it can only be encountered when making a piece. */
2515 internal_error (__FILE__
, __LINE__
, _("invalid location type"));
2519 set_value_initialized (retval
, ctx
->initialized
);
2521 do_cleanups (old_chain
);
2526 /* The exported interface to dwarf2_evaluate_loc_desc_full; it always
2527 passes 0 as the byte_offset. */
2530 dwarf2_evaluate_loc_desc (struct type
*type
, struct frame_info
*frame
,
2531 const gdb_byte
*data
, size_t size
,
2532 struct dwarf2_per_cu_data
*per_cu
)
2534 return dwarf2_evaluate_loc_desc_full (type
, frame
, data
, size
, per_cu
, 0);
2537 /* Evaluates a dwarf expression and stores the result in VAL, expecting
2538 that the dwarf expression only produces a single CORE_ADDR. FRAME is the
2539 frame in which the expression is evaluated. ADDR is a context (location of
2540 a variable) and might be needed to evaluate the location expression.
2541 Returns 1 on success, 0 otherwise. */
2544 dwarf2_locexpr_baton_eval (const struct dwarf2_locexpr_baton
*dlbaton
,
2545 struct frame_info
*frame
,
2549 struct dwarf_expr_context
*ctx
;
2550 struct dwarf_expr_baton baton
;
2551 struct objfile
*objfile
;
2552 struct cleanup
*cleanup
;
2554 if (dlbaton
== NULL
|| dlbaton
->size
== 0)
2557 ctx
= new_dwarf_expr_context ();
2558 cleanup
= make_cleanup_free_dwarf_expr_context (ctx
);
2560 baton
.frame
= frame
;
2561 baton
.per_cu
= dlbaton
->per_cu
;
2562 baton
.obj_address
= addr
;
2564 objfile
= dwarf2_per_cu_objfile (dlbaton
->per_cu
);
2566 ctx
->gdbarch
= get_objfile_arch (objfile
);
2567 ctx
->addr_size
= dwarf2_per_cu_addr_size (dlbaton
->per_cu
);
2568 ctx
->ref_addr_size
= dwarf2_per_cu_ref_addr_size (dlbaton
->per_cu
);
2569 ctx
->offset
= dwarf2_per_cu_text_offset (dlbaton
->per_cu
);
2570 ctx
->funcs
= &dwarf_expr_ctx_funcs
;
2571 ctx
->baton
= &baton
;
2573 dwarf_expr_eval (ctx
, dlbaton
->data
, dlbaton
->size
);
2575 switch (ctx
->location
)
2577 case DWARF_VALUE_REGISTER
:
2578 case DWARF_VALUE_MEMORY
:
2579 case DWARF_VALUE_STACK
:
2580 *valp
= dwarf_expr_fetch_address (ctx
, 0);
2581 if (ctx
->location
== DWARF_VALUE_REGISTER
)
2582 *valp
= dwarf_expr_read_addr_from_reg (&baton
, *valp
);
2583 do_cleanups (cleanup
);
2585 case DWARF_VALUE_LITERAL
:
2586 *valp
= extract_signed_integer (ctx
->data
, ctx
->len
,
2587 gdbarch_byte_order (ctx
->gdbarch
));
2588 do_cleanups (cleanup
);
2590 /* Unsupported dwarf values. */
2591 case DWARF_VALUE_OPTIMIZED_OUT
:
2592 case DWARF_VALUE_IMPLICIT_POINTER
:
2596 do_cleanups (cleanup
);
2600 /* See dwarf2loc.h. */
2603 dwarf2_evaluate_property (const struct dynamic_prop
*prop
,
2604 struct frame_info
*frame
,
2605 struct property_addr_info
*addr_stack
,
2611 if (frame
== NULL
&& has_stack_frames ())
2612 frame
= get_selected_frame (NULL
);
2618 const struct dwarf2_property_baton
*baton
2619 = (const struct dwarf2_property_baton
*) prop
->data
.baton
;
2621 if (dwarf2_locexpr_baton_eval (&baton
->locexpr
, frame
,
2622 addr_stack
? addr_stack
->addr
: 0,
2625 if (baton
->referenced_type
)
2627 struct value
*val
= value_at (baton
->referenced_type
, *value
);
2629 *value
= value_as_address (val
);
2638 struct dwarf2_property_baton
*baton
2639 = (struct dwarf2_property_baton
*) prop
->data
.baton
;
2640 CORE_ADDR pc
= get_frame_address_in_block (frame
);
2641 const gdb_byte
*data
;
2645 data
= dwarf2_find_location_expression (&baton
->loclist
, &size
, pc
);
2648 val
= dwarf2_evaluate_loc_desc (baton
->referenced_type
, frame
, data
,
2649 size
, baton
->loclist
.per_cu
);
2650 if (!value_optimized_out (val
))
2652 *value
= value_as_address (val
);
2660 *value
= prop
->data
.const_val
;
2663 case PROP_ADDR_OFFSET
:
2665 struct dwarf2_property_baton
*baton
2666 = (struct dwarf2_property_baton
*) prop
->data
.baton
;
2667 struct property_addr_info
*pinfo
;
2670 for (pinfo
= addr_stack
; pinfo
!= NULL
; pinfo
= pinfo
->next
)
2671 if (pinfo
->type
== baton
->referenced_type
)
2674 error (_("cannot find reference address for offset property"));
2675 if (pinfo
->valaddr
!= NULL
)
2676 val
= value_from_contents
2677 (baton
->offset_info
.type
,
2678 pinfo
->valaddr
+ baton
->offset_info
.offset
);
2680 val
= value_at (baton
->offset_info
.type
,
2681 pinfo
->addr
+ baton
->offset_info
.offset
);
2682 *value
= value_as_address (val
);
2690 /* See dwarf2loc.h. */
2693 dwarf2_compile_property_to_c (struct ui_file
*stream
,
2694 const char *result_name
,
2695 struct gdbarch
*gdbarch
,
2696 unsigned char *registers_used
,
2697 const struct dynamic_prop
*prop
,
2701 struct dwarf2_property_baton
*baton
2702 = (struct dwarf2_property_baton
*) prop
->data
.baton
;
2703 const gdb_byte
*data
;
2705 struct dwarf2_per_cu_data
*per_cu
;
2707 if (prop
->kind
== PROP_LOCEXPR
)
2709 data
= baton
->locexpr
.data
;
2710 size
= baton
->locexpr
.size
;
2711 per_cu
= baton
->locexpr
.per_cu
;
2715 gdb_assert (prop
->kind
== PROP_LOCLIST
);
2717 data
= dwarf2_find_location_expression (&baton
->loclist
, &size
, pc
);
2718 per_cu
= baton
->loclist
.per_cu
;
2721 compile_dwarf_bounds_to_c (stream
, result_name
, prop
, sym
, pc
,
2722 gdbarch
, registers_used
,
2723 dwarf2_per_cu_addr_size (per_cu
),
2724 data
, data
+ size
, per_cu
);
2728 /* Helper functions and baton for dwarf2_loc_desc_needs_frame. */
2730 struct needs_frame_baton
2733 struct dwarf2_per_cu_data
*per_cu
;
2736 /* Reads from registers do require a frame. */
2738 needs_frame_read_addr_from_reg (void *baton
, int regnum
)
2740 struct needs_frame_baton
*nf_baton
= (struct needs_frame_baton
*) baton
;
2742 nf_baton
->needs_frame
= 1;
2746 /* struct dwarf_expr_context_funcs' "get_reg_value" callback:
2747 Reads from registers do require a frame. */
2749 static struct value
*
2750 needs_frame_get_reg_value (void *baton
, struct type
*type
, int regnum
)
2752 struct needs_frame_baton
*nf_baton
= (struct needs_frame_baton
*) baton
;
2754 nf_baton
->needs_frame
= 1;
2755 return value_zero (type
, not_lval
);
2758 /* Reads from memory do not require a frame. */
2760 needs_frame_read_mem (void *baton
, gdb_byte
*buf
, CORE_ADDR addr
, size_t len
)
2762 memset (buf
, 0, len
);
2765 /* Frame-relative accesses do require a frame. */
2767 needs_frame_frame_base (void *baton
, const gdb_byte
**start
, size_t * length
)
2769 static gdb_byte lit0
= DW_OP_lit0
;
2770 struct needs_frame_baton
*nf_baton
= (struct needs_frame_baton
*) baton
;
2775 nf_baton
->needs_frame
= 1;
2778 /* CFA accesses require a frame. */
2781 needs_frame_frame_cfa (void *baton
)
2783 struct needs_frame_baton
*nf_baton
= (struct needs_frame_baton
*) baton
;
2785 nf_baton
->needs_frame
= 1;
2789 /* Thread-local accesses do require a frame. */
2791 needs_frame_tls_address (void *baton
, CORE_ADDR offset
)
2793 struct needs_frame_baton
*nf_baton
= (struct needs_frame_baton
*) baton
;
2795 nf_baton
->needs_frame
= 1;
2799 /* Helper interface of per_cu_dwarf_call for dwarf2_loc_desc_needs_frame. */
2802 needs_frame_dwarf_call (struct dwarf_expr_context
*ctx
, cu_offset die_offset
)
2804 struct needs_frame_baton
*nf_baton
= (struct needs_frame_baton
*) ctx
->baton
;
2806 per_cu_dwarf_call (ctx
, die_offset
, nf_baton
->per_cu
,
2807 ctx
->funcs
->get_frame_pc
, ctx
->baton
);
2810 /* DW_OP_GNU_entry_value accesses require a caller, therefore a frame. */
2813 needs_dwarf_reg_entry_value (struct dwarf_expr_context
*ctx
,
2814 enum call_site_parameter_kind kind
,
2815 union call_site_parameter_u kind_u
, int deref_size
)
2817 struct needs_frame_baton
*nf_baton
= (struct needs_frame_baton
*) ctx
->baton
;
2819 nf_baton
->needs_frame
= 1;
2821 /* The expression may require some stub values on DWARF stack. */
2822 dwarf_expr_push_address (ctx
, 0, 0);
2825 /* DW_OP_GNU_addr_index doesn't require a frame. */
2828 needs_get_addr_index (void *baton
, unsigned int index
)
2830 /* Nothing to do. */
2834 /* DW_OP_push_object_address has a frame already passed through. */
2837 needs_get_obj_addr (void *baton
)
2839 /* Nothing to do. */
2843 /* Virtual method table for dwarf2_loc_desc_needs_frame below. */
2845 static const struct dwarf_expr_context_funcs needs_frame_ctx_funcs
=
2847 needs_frame_read_addr_from_reg
,
2848 needs_frame_get_reg_value
,
2849 needs_frame_read_mem
,
2850 needs_frame_frame_base
,
2851 needs_frame_frame_cfa
,
2852 needs_frame_frame_cfa
, /* get_frame_pc */
2853 needs_frame_tls_address
,
2854 needs_frame_dwarf_call
,
2855 NULL
, /* get_base_type */
2856 needs_dwarf_reg_entry_value
,
2857 needs_get_addr_index
,
2861 /* Return non-zero iff the location expression at DATA (length SIZE)
2862 requires a frame to evaluate. */
2865 dwarf2_loc_desc_needs_frame (const gdb_byte
*data
, size_t size
,
2866 struct dwarf2_per_cu_data
*per_cu
)
2868 struct needs_frame_baton baton
;
2869 struct dwarf_expr_context
*ctx
;
2871 struct cleanup
*old_chain
;
2872 struct objfile
*objfile
= dwarf2_per_cu_objfile (per_cu
);
2874 baton
.needs_frame
= 0;
2875 baton
.per_cu
= per_cu
;
2877 ctx
= new_dwarf_expr_context ();
2878 old_chain
= make_cleanup_free_dwarf_expr_context (ctx
);
2879 make_cleanup_value_free_to_mark (value_mark ());
2881 ctx
->gdbarch
= get_objfile_arch (objfile
);
2882 ctx
->addr_size
= dwarf2_per_cu_addr_size (per_cu
);
2883 ctx
->ref_addr_size
= dwarf2_per_cu_ref_addr_size (per_cu
);
2884 ctx
->offset
= dwarf2_per_cu_text_offset (per_cu
);
2885 ctx
->baton
= &baton
;
2886 ctx
->funcs
= &needs_frame_ctx_funcs
;
2888 dwarf_expr_eval (ctx
, data
, size
);
2890 in_reg
= ctx
->location
== DWARF_VALUE_REGISTER
;
2892 if (ctx
->num_pieces
> 0)
2896 /* If the location has several pieces, and any of them are in
2897 registers, then we will need a frame to fetch them from. */
2898 for (i
= 0; i
< ctx
->num_pieces
; i
++)
2899 if (ctx
->pieces
[i
].location
== DWARF_VALUE_REGISTER
)
2903 do_cleanups (old_chain
);
2905 return baton
.needs_frame
|| in_reg
;
2908 /* A helper function that throws an unimplemented error mentioning a
2909 given DWARF operator. */
2912 unimplemented (unsigned int op
)
2914 const char *name
= get_DW_OP_name (op
);
2917 error (_("DWARF operator %s cannot be translated to an agent expression"),
2920 error (_("Unknown DWARF operator 0x%02x cannot be translated "
2921 "to an agent expression"),
2927 This is basically a wrapper on gdbarch_dwarf2_reg_to_regnum so that we
2928 can issue a complaint, which is better than having every target's
2929 implementation of dwarf2_reg_to_regnum do it. */
2932 dwarf_reg_to_regnum (struct gdbarch
*arch
, int dwarf_reg
)
2934 int reg
= gdbarch_dwarf2_reg_to_regnum (arch
, dwarf_reg
);
2938 complaint (&symfile_complaints
,
2939 _("bad DWARF register number %d"), dwarf_reg
);
2944 /* Subroutine of dwarf_reg_to_regnum_or_error to simplify it.
2945 Throw an error because DWARF_REG is bad. */
2948 throw_bad_regnum_error (ULONGEST dwarf_reg
)
2950 /* Still want to print -1 as "-1".
2951 We *could* have int and ULONGEST versions of dwarf2_reg_to_regnum_or_error
2952 but that's overkill for now. */
2953 if ((int) dwarf_reg
== dwarf_reg
)
2954 error (_("Unable to access DWARF register number %d"), (int) dwarf_reg
);
2955 error (_("Unable to access DWARF register number %s"),
2956 pulongest (dwarf_reg
));
2959 /* See dwarf2loc.h. */
2962 dwarf_reg_to_regnum_or_error (struct gdbarch
*arch
, ULONGEST dwarf_reg
)
2966 if (dwarf_reg
> INT_MAX
)
2967 throw_bad_regnum_error (dwarf_reg
);
2968 /* Yes, we will end up issuing a complaint and an error if DWARF_REG is
2969 bad, but that's ok. */
2970 reg
= dwarf_reg_to_regnum (arch
, (int) dwarf_reg
);
2972 throw_bad_regnum_error (dwarf_reg
);
2976 /* A helper function that emits an access to memory. ARCH is the
2977 target architecture. EXPR is the expression which we are building.
2978 NBITS is the number of bits we want to read. This emits the
2979 opcodes needed to read the memory and then extract the desired
2983 access_memory (struct gdbarch
*arch
, struct agent_expr
*expr
, ULONGEST nbits
)
2985 ULONGEST nbytes
= (nbits
+ 7) / 8;
2987 gdb_assert (nbytes
> 0 && nbytes
<= sizeof (LONGEST
));
2990 ax_trace_quick (expr
, nbytes
);
2993 ax_simple (expr
, aop_ref8
);
2994 else if (nbits
<= 16)
2995 ax_simple (expr
, aop_ref16
);
2996 else if (nbits
<= 32)
2997 ax_simple (expr
, aop_ref32
);
2999 ax_simple (expr
, aop_ref64
);
3001 /* If we read exactly the number of bytes we wanted, we're done. */
3002 if (8 * nbytes
== nbits
)
3005 if (gdbarch_bits_big_endian (arch
))
3007 /* On a bits-big-endian machine, we want the high-order
3009 ax_const_l (expr
, 8 * nbytes
- nbits
);
3010 ax_simple (expr
, aop_rsh_unsigned
);
3014 /* On a bits-little-endian box, we want the low-order NBITS. */
3015 ax_zero_ext (expr
, nbits
);
3019 /* A helper function to return the frame's PC. */
3022 get_ax_pc (void *baton
)
3024 struct agent_expr
*expr
= (struct agent_expr
*) baton
;
3029 /* Compile a DWARF location expression to an agent expression.
3031 EXPR is the agent expression we are building.
3032 LOC is the agent value we modify.
3033 ARCH is the architecture.
3034 ADDR_SIZE is the size of addresses, in bytes.
3035 OP_PTR is the start of the location expression.
3036 OP_END is one past the last byte of the location expression.
3038 This will throw an exception for various kinds of errors -- for
3039 example, if the expression cannot be compiled, or if the expression
3043 dwarf2_compile_expr_to_ax (struct agent_expr
*expr
, struct axs_value
*loc
,
3044 struct gdbarch
*arch
, unsigned int addr_size
,
3045 const gdb_byte
*op_ptr
, const gdb_byte
*op_end
,
3046 struct dwarf2_per_cu_data
*per_cu
)
3048 struct cleanup
*cleanups
;
3050 VEC(int) *dw_labels
= NULL
, *patches
= NULL
;
3051 const gdb_byte
* const base
= op_ptr
;
3052 const gdb_byte
*previous_piece
= op_ptr
;
3053 enum bfd_endian byte_order
= gdbarch_byte_order (arch
);
3054 ULONGEST bits_collected
= 0;
3055 unsigned int addr_size_bits
= 8 * addr_size
;
3056 int bits_big_endian
= gdbarch_bits_big_endian (arch
);
3058 offsets
= XNEWVEC (int, op_end
- op_ptr
);
3059 cleanups
= make_cleanup (xfree
, offsets
);
3061 for (i
= 0; i
< op_end
- op_ptr
; ++i
)
3064 make_cleanup (VEC_cleanup (int), &dw_labels
);
3065 make_cleanup (VEC_cleanup (int), &patches
);
3067 /* By default we are making an address. */
3068 loc
->kind
= axs_lvalue_memory
;
3070 while (op_ptr
< op_end
)
3072 enum dwarf_location_atom op
= (enum dwarf_location_atom
) *op_ptr
;
3073 uint64_t uoffset
, reg
;
3077 offsets
[op_ptr
- base
] = expr
->len
;
3080 /* Our basic approach to code generation is to map DWARF
3081 operations directly to AX operations. However, there are
3084 First, DWARF works on address-sized units, but AX always uses
3085 LONGEST. For most operations we simply ignore this
3086 difference; instead we generate sign extensions as needed
3087 before division and comparison operations. It would be nice
3088 to omit the sign extensions, but there is no way to determine
3089 the size of the target's LONGEST. (This code uses the size
3090 of the host LONGEST in some cases -- that is a bug but it is
3093 Second, some DWARF operations cannot be translated to AX.
3094 For these we simply fail. See
3095 http://sourceware.org/bugzilla/show_bug.cgi?id=11662. */
3130 ax_const_l (expr
, op
- DW_OP_lit0
);
3134 uoffset
= extract_unsigned_integer (op_ptr
, addr_size
, byte_order
);
3135 op_ptr
+= addr_size
;
3136 /* Some versions of GCC emit DW_OP_addr before
3137 DW_OP_GNU_push_tls_address. In this case the value is an
3138 index, not an address. We don't support things like
3139 branching between the address and the TLS op. */
3140 if (op_ptr
>= op_end
|| *op_ptr
!= DW_OP_GNU_push_tls_address
)
3141 uoffset
+= dwarf2_per_cu_text_offset (per_cu
);
3142 ax_const_l (expr
, uoffset
);
3146 ax_const_l (expr
, extract_unsigned_integer (op_ptr
, 1, byte_order
));
3150 ax_const_l (expr
, extract_signed_integer (op_ptr
, 1, byte_order
));
3154 ax_const_l (expr
, extract_unsigned_integer (op_ptr
, 2, byte_order
));
3158 ax_const_l (expr
, extract_signed_integer (op_ptr
, 2, byte_order
));
3162 ax_const_l (expr
, extract_unsigned_integer (op_ptr
, 4, byte_order
));
3166 ax_const_l (expr
, extract_signed_integer (op_ptr
, 4, byte_order
));
3170 ax_const_l (expr
, extract_unsigned_integer (op_ptr
, 8, byte_order
));
3174 ax_const_l (expr
, extract_signed_integer (op_ptr
, 8, byte_order
));
3178 op_ptr
= safe_read_uleb128 (op_ptr
, op_end
, &uoffset
);
3179 ax_const_l (expr
, uoffset
);
3182 op_ptr
= safe_read_sleb128 (op_ptr
, op_end
, &offset
);
3183 ax_const_l (expr
, offset
);
3218 dwarf_expr_require_composition (op_ptr
, op_end
, "DW_OP_regx");
3219 loc
->u
.reg
= dwarf_reg_to_regnum_or_error (arch
, op
- DW_OP_reg0
);
3220 loc
->kind
= axs_lvalue_register
;
3224 op_ptr
= safe_read_uleb128 (op_ptr
, op_end
, ®
);
3225 dwarf_expr_require_composition (op_ptr
, op_end
, "DW_OP_regx");
3226 loc
->u
.reg
= dwarf_reg_to_regnum_or_error (arch
, reg
);
3227 loc
->kind
= axs_lvalue_register
;
3230 case DW_OP_implicit_value
:
3234 op_ptr
= safe_read_uleb128 (op_ptr
, op_end
, &len
);
3235 if (op_ptr
+ len
> op_end
)
3236 error (_("DW_OP_implicit_value: too few bytes available."));
3237 if (len
> sizeof (ULONGEST
))
3238 error (_("Cannot translate DW_OP_implicit_value of %d bytes"),
3241 ax_const_l (expr
, extract_unsigned_integer (op_ptr
, len
,
3244 dwarf_expr_require_composition (op_ptr
, op_end
,
3245 "DW_OP_implicit_value");
3247 loc
->kind
= axs_rvalue
;
3251 case DW_OP_stack_value
:
3252 dwarf_expr_require_composition (op_ptr
, op_end
, "DW_OP_stack_value");
3253 loc
->kind
= axs_rvalue
;
3288 op_ptr
= safe_read_sleb128 (op_ptr
, op_end
, &offset
);
3289 i
= dwarf_reg_to_regnum_or_error (arch
, op
- DW_OP_breg0
);
3293 ax_const_l (expr
, offset
);
3294 ax_simple (expr
, aop_add
);
3299 op_ptr
= safe_read_uleb128 (op_ptr
, op_end
, ®
);
3300 op_ptr
= safe_read_sleb128 (op_ptr
, op_end
, &offset
);
3301 i
= dwarf_reg_to_regnum_or_error (arch
, reg
);
3305 ax_const_l (expr
, offset
);
3306 ax_simple (expr
, aop_add
);
3312 const gdb_byte
*datastart
;
3314 const struct block
*b
;
3315 struct symbol
*framefunc
;
3317 b
= block_for_pc (expr
->scope
);
3320 error (_("No block found for address"));
3322 framefunc
= block_linkage_function (b
);
3325 error (_("No function found for block"));
3327 func_get_frame_base_dwarf_block (framefunc
, expr
->scope
,
3328 &datastart
, &datalen
);
3330 op_ptr
= safe_read_sleb128 (op_ptr
, op_end
, &offset
);
3331 dwarf2_compile_expr_to_ax (expr
, loc
, arch
, addr_size
, datastart
,
3332 datastart
+ datalen
, per_cu
);
3333 if (loc
->kind
== axs_lvalue_register
)
3334 require_rvalue (expr
, loc
);
3338 ax_const_l (expr
, offset
);
3339 ax_simple (expr
, aop_add
);
3342 loc
->kind
= axs_lvalue_memory
;
3347 ax_simple (expr
, aop_dup
);
3351 ax_simple (expr
, aop_pop
);
3356 ax_pick (expr
, offset
);
3360 ax_simple (expr
, aop_swap
);
3368 ax_simple (expr
, aop_rot
);
3372 case DW_OP_deref_size
:
3376 if (op
== DW_OP_deref_size
)
3381 if (size
!= 1 && size
!= 2 && size
!= 4 && size
!= 8)
3382 error (_("Unsupported size %d in %s"),
3383 size
, get_DW_OP_name (op
));
3384 access_memory (arch
, expr
, size
* TARGET_CHAR_BIT
);
3389 /* Sign extend the operand. */
3390 ax_ext (expr
, addr_size_bits
);
3391 ax_simple (expr
, aop_dup
);
3392 ax_const_l (expr
, 0);
3393 ax_simple (expr
, aop_less_signed
);
3394 ax_simple (expr
, aop_log_not
);
3395 i
= ax_goto (expr
, aop_if_goto
);
3396 /* We have to emit 0 - X. */
3397 ax_const_l (expr
, 0);
3398 ax_simple (expr
, aop_swap
);
3399 ax_simple (expr
, aop_sub
);
3400 ax_label (expr
, i
, expr
->len
);
3404 /* No need to sign extend here. */
3405 ax_const_l (expr
, 0);
3406 ax_simple (expr
, aop_swap
);
3407 ax_simple (expr
, aop_sub
);
3411 /* Sign extend the operand. */
3412 ax_ext (expr
, addr_size_bits
);
3413 ax_simple (expr
, aop_bit_not
);
3416 case DW_OP_plus_uconst
:
3417 op_ptr
= safe_read_uleb128 (op_ptr
, op_end
, ®
);
3418 /* It would be really weird to emit `DW_OP_plus_uconst 0',
3419 but we micro-optimize anyhow. */
3422 ax_const_l (expr
, reg
);
3423 ax_simple (expr
, aop_add
);
3428 ax_simple (expr
, aop_bit_and
);
3432 /* Sign extend the operands. */
3433 ax_ext (expr
, addr_size_bits
);
3434 ax_simple (expr
, aop_swap
);
3435 ax_ext (expr
, addr_size_bits
);
3436 ax_simple (expr
, aop_swap
);
3437 ax_simple (expr
, aop_div_signed
);
3441 ax_simple (expr
, aop_sub
);
3445 ax_simple (expr
, aop_rem_unsigned
);
3449 ax_simple (expr
, aop_mul
);
3453 ax_simple (expr
, aop_bit_or
);
3457 ax_simple (expr
, aop_add
);
3461 ax_simple (expr
, aop_lsh
);
3465 ax_simple (expr
, aop_rsh_unsigned
);
3469 ax_simple (expr
, aop_rsh_signed
);
3473 ax_simple (expr
, aop_bit_xor
);
3477 /* Sign extend the operands. */
3478 ax_ext (expr
, addr_size_bits
);
3479 ax_simple (expr
, aop_swap
);
3480 ax_ext (expr
, addr_size_bits
);
3481 /* Note no swap here: A <= B is !(B < A). */
3482 ax_simple (expr
, aop_less_signed
);
3483 ax_simple (expr
, aop_log_not
);
3487 /* Sign extend the operands. */
3488 ax_ext (expr
, addr_size_bits
);
3489 ax_simple (expr
, aop_swap
);
3490 ax_ext (expr
, addr_size_bits
);
3491 ax_simple (expr
, aop_swap
);
3492 /* A >= B is !(A < B). */
3493 ax_simple (expr
, aop_less_signed
);
3494 ax_simple (expr
, aop_log_not
);
3498 /* Sign extend the operands. */
3499 ax_ext (expr
, addr_size_bits
);
3500 ax_simple (expr
, aop_swap
);
3501 ax_ext (expr
, addr_size_bits
);
3502 /* No need for a second swap here. */
3503 ax_simple (expr
, aop_equal
);
3507 /* Sign extend the operands. */
3508 ax_ext (expr
, addr_size_bits
);
3509 ax_simple (expr
, aop_swap
);
3510 ax_ext (expr
, addr_size_bits
);
3511 ax_simple (expr
, aop_swap
);
3512 ax_simple (expr
, aop_less_signed
);
3516 /* Sign extend the operands. */
3517 ax_ext (expr
, addr_size_bits
);
3518 ax_simple (expr
, aop_swap
);
3519 ax_ext (expr
, addr_size_bits
);
3520 /* Note no swap here: A > B is B < A. */
3521 ax_simple (expr
, aop_less_signed
);
3525 /* Sign extend the operands. */
3526 ax_ext (expr
, addr_size_bits
);
3527 ax_simple (expr
, aop_swap
);
3528 ax_ext (expr
, addr_size_bits
);
3529 /* No need for a swap here. */
3530 ax_simple (expr
, aop_equal
);
3531 ax_simple (expr
, aop_log_not
);
3534 case DW_OP_call_frame_cfa
:
3537 CORE_ADDR text_offset
;
3539 const gdb_byte
*cfa_start
, *cfa_end
;
3541 if (dwarf2_fetch_cfa_info (arch
, expr
->scope
, per_cu
,
3543 &text_offset
, &cfa_start
, &cfa_end
))
3546 ax_reg (expr
, regnum
);
3549 ax_const_l (expr
, off
);
3550 ax_simple (expr
, aop_add
);
3555 /* Another expression. */
3556 ax_const_l (expr
, text_offset
);
3557 dwarf2_compile_expr_to_ax (expr
, loc
, arch
, addr_size
,
3558 cfa_start
, cfa_end
, per_cu
);
3561 loc
->kind
= axs_lvalue_memory
;
3565 case DW_OP_GNU_push_tls_address
:
3569 case DW_OP_push_object_address
:
3574 offset
= extract_signed_integer (op_ptr
, 2, byte_order
);
3576 i
= ax_goto (expr
, aop_goto
);
3577 VEC_safe_push (int, dw_labels
, op_ptr
+ offset
- base
);
3578 VEC_safe_push (int, patches
, i
);
3582 offset
= extract_signed_integer (op_ptr
, 2, byte_order
);
3584 /* Zero extend the operand. */
3585 ax_zero_ext (expr
, addr_size_bits
);
3586 i
= ax_goto (expr
, aop_if_goto
);
3587 VEC_safe_push (int, dw_labels
, op_ptr
+ offset
- base
);
3588 VEC_safe_push (int, patches
, i
);
3595 case DW_OP_bit_piece
:
3597 uint64_t size
, offset
;
3599 if (op_ptr
- 1 == previous_piece
)
3600 error (_("Cannot translate empty pieces to agent expressions"));
3601 previous_piece
= op_ptr
- 1;
3603 op_ptr
= safe_read_uleb128 (op_ptr
, op_end
, &size
);
3604 if (op
== DW_OP_piece
)
3610 op_ptr
= safe_read_uleb128 (op_ptr
, op_end
, &offset
);
3612 if (bits_collected
+ size
> 8 * sizeof (LONGEST
))
3613 error (_("Expression pieces exceed word size"));
3615 /* Access the bits. */
3618 case axs_lvalue_register
:
3619 ax_reg (expr
, loc
->u
.reg
);
3622 case axs_lvalue_memory
:
3623 /* Offset the pointer, if needed. */
3626 ax_const_l (expr
, offset
/ 8);
3627 ax_simple (expr
, aop_add
);
3630 access_memory (arch
, expr
, size
);
3634 /* For a bits-big-endian target, shift up what we already
3635 have. For a bits-little-endian target, shift up the
3636 new data. Note that there is a potential bug here if
3637 the DWARF expression leaves multiple values on the
3639 if (bits_collected
> 0)
3641 if (bits_big_endian
)
3643 ax_simple (expr
, aop_swap
);
3644 ax_const_l (expr
, size
);
3645 ax_simple (expr
, aop_lsh
);
3646 /* We don't need a second swap here, because
3647 aop_bit_or is symmetric. */
3651 ax_const_l (expr
, size
);
3652 ax_simple (expr
, aop_lsh
);
3654 ax_simple (expr
, aop_bit_or
);
3657 bits_collected
+= size
;
3658 loc
->kind
= axs_rvalue
;
3662 case DW_OP_GNU_uninit
:
3668 struct dwarf2_locexpr_baton block
;
3669 int size
= (op
== DW_OP_call2
? 2 : 4);
3672 uoffset
= extract_unsigned_integer (op_ptr
, size
, byte_order
);
3675 offset
.cu_off
= uoffset
;
3676 block
= dwarf2_fetch_die_loc_cu_off (offset
, per_cu
,
3679 /* DW_OP_call_ref is currently not supported. */
3680 gdb_assert (block
.per_cu
== per_cu
);
3682 dwarf2_compile_expr_to_ax (expr
, loc
, arch
, addr_size
,
3683 block
.data
, block
.data
+ block
.size
,
3688 case DW_OP_call_ref
:
3696 /* Patch all the branches we emitted. */
3697 for (i
= 0; i
< VEC_length (int, patches
); ++i
)
3699 int targ
= offsets
[VEC_index (int, dw_labels
, i
)];
3701 internal_error (__FILE__
, __LINE__
, _("invalid label"));
3702 ax_label (expr
, VEC_index (int, patches
, i
), targ
);
3705 do_cleanups (cleanups
);
3709 /* Return the value of SYMBOL in FRAME using the DWARF-2 expression
3710 evaluator to calculate the location. */
3711 static struct value
*
3712 locexpr_read_variable (struct symbol
*symbol
, struct frame_info
*frame
)
3714 struct dwarf2_locexpr_baton
*dlbaton
3715 = (struct dwarf2_locexpr_baton
*) SYMBOL_LOCATION_BATON (symbol
);
3718 val
= dwarf2_evaluate_loc_desc (SYMBOL_TYPE (symbol
), frame
, dlbaton
->data
,
3719 dlbaton
->size
, dlbaton
->per_cu
);
3724 /* Return the value of SYMBOL in FRAME at (callee) FRAME's function
3725 entry. SYMBOL should be a function parameter, otherwise NO_ENTRY_VALUE_ERROR
3728 static struct value
*
3729 locexpr_read_variable_at_entry (struct symbol
*symbol
, struct frame_info
*frame
)
3731 struct dwarf2_locexpr_baton
*dlbaton
3732 = (struct dwarf2_locexpr_baton
*) SYMBOL_LOCATION_BATON (symbol
);
3734 return value_of_dwarf_block_entry (SYMBOL_TYPE (symbol
), frame
, dlbaton
->data
,
3738 /* Return non-zero iff we need a frame to evaluate SYMBOL. */
3740 locexpr_read_needs_frame (struct symbol
*symbol
)
3742 struct dwarf2_locexpr_baton
*dlbaton
3743 = (struct dwarf2_locexpr_baton
*) SYMBOL_LOCATION_BATON (symbol
);
3745 return dwarf2_loc_desc_needs_frame (dlbaton
->data
, dlbaton
->size
,
3749 /* Return true if DATA points to the end of a piece. END is one past
3750 the last byte in the expression. */
3753 piece_end_p (const gdb_byte
*data
, const gdb_byte
*end
)
3755 return data
== end
|| data
[0] == DW_OP_piece
|| data
[0] == DW_OP_bit_piece
;
3758 /* Helper for locexpr_describe_location_piece that finds the name of a
3762 locexpr_regname (struct gdbarch
*gdbarch
, int dwarf_regnum
)
3766 /* This doesn't use dwarf_reg_to_regnum_or_error on purpose.
3767 We'd rather print *something* here than throw an error. */
3768 regnum
= dwarf_reg_to_regnum (gdbarch
, dwarf_regnum
);
3769 /* gdbarch_register_name may just return "", return something more
3770 descriptive for bad register numbers. */
3773 /* The text is output as "$bad_register_number".
3774 That is why we use the underscores. */
3775 return _("bad_register_number");
3777 return gdbarch_register_name (gdbarch
, regnum
);
3780 /* Nicely describe a single piece of a location, returning an updated
3781 position in the bytecode sequence. This function cannot recognize
3782 all locations; if a location is not recognized, it simply returns
3783 DATA. If there is an error during reading, e.g. we run off the end
3784 of the buffer, an error is thrown. */
3786 static const gdb_byte
*
3787 locexpr_describe_location_piece (struct symbol
*symbol
, struct ui_file
*stream
,
3788 CORE_ADDR addr
, struct objfile
*objfile
,
3789 struct dwarf2_per_cu_data
*per_cu
,
3790 const gdb_byte
*data
, const gdb_byte
*end
,
3791 unsigned int addr_size
)
3793 struct gdbarch
*gdbarch
= get_objfile_arch (objfile
);
3796 if (data
[0] >= DW_OP_reg0
&& data
[0] <= DW_OP_reg31
)
3798 fprintf_filtered (stream
, _("a variable in $%s"),
3799 locexpr_regname (gdbarch
, data
[0] - DW_OP_reg0
));
3802 else if (data
[0] == DW_OP_regx
)
3806 data
= safe_read_uleb128 (data
+ 1, end
, ®
);
3807 fprintf_filtered (stream
, _("a variable in $%s"),
3808 locexpr_regname (gdbarch
, reg
));
3810 else if (data
[0] == DW_OP_fbreg
)
3812 const struct block
*b
;
3813 struct symbol
*framefunc
;
3815 int64_t frame_offset
;
3816 const gdb_byte
*base_data
, *new_data
, *save_data
= data
;
3818 int64_t base_offset
= 0;
3820 new_data
= safe_read_sleb128 (data
+ 1, end
, &frame_offset
);
3821 if (!piece_end_p (new_data
, end
))
3825 b
= block_for_pc (addr
);
3828 error (_("No block found for address for symbol \"%s\"."),
3829 SYMBOL_PRINT_NAME (symbol
));
3831 framefunc
= block_linkage_function (b
);
3834 error (_("No function found for block for symbol \"%s\"."),
3835 SYMBOL_PRINT_NAME (symbol
));
3837 func_get_frame_base_dwarf_block (framefunc
, addr
, &base_data
, &base_size
);
3839 if (base_data
[0] >= DW_OP_breg0
&& base_data
[0] <= DW_OP_breg31
)
3841 const gdb_byte
*buf_end
;
3843 frame_reg
= base_data
[0] - DW_OP_breg0
;
3844 buf_end
= safe_read_sleb128 (base_data
+ 1, base_data
+ base_size
,
3846 if (buf_end
!= base_data
+ base_size
)
3847 error (_("Unexpected opcode after "
3848 "DW_OP_breg%u for symbol \"%s\"."),
3849 frame_reg
, SYMBOL_PRINT_NAME (symbol
));
3851 else if (base_data
[0] >= DW_OP_reg0
&& base_data
[0] <= DW_OP_reg31
)
3853 /* The frame base is just the register, with no offset. */
3854 frame_reg
= base_data
[0] - DW_OP_reg0
;
3859 /* We don't know what to do with the frame base expression,
3860 so we can't trace this variable; give up. */
3864 fprintf_filtered (stream
,
3865 _("a variable at frame base reg $%s offset %s+%s"),
3866 locexpr_regname (gdbarch
, frame_reg
),
3867 plongest (base_offset
), plongest (frame_offset
));
3869 else if (data
[0] >= DW_OP_breg0
&& data
[0] <= DW_OP_breg31
3870 && piece_end_p (data
, end
))
3874 data
= safe_read_sleb128 (data
+ 1, end
, &offset
);
3876 fprintf_filtered (stream
,
3877 _("a variable at offset %s from base reg $%s"),
3879 locexpr_regname (gdbarch
, data
[0] - DW_OP_breg0
));
3882 /* The location expression for a TLS variable looks like this (on a
3885 DW_AT_location : 10 byte block: 3 4 0 0 0 0 0 0 0 e0
3886 (DW_OP_addr: 4; DW_OP_GNU_push_tls_address)
3888 0x3 is the encoding for DW_OP_addr, which has an operand as long
3889 as the size of an address on the target machine (here is 8
3890 bytes). Note that more recent version of GCC emit DW_OP_const4u
3891 or DW_OP_const8u, depending on address size, rather than
3892 DW_OP_addr. 0xe0 is the encoding for DW_OP_GNU_push_tls_address.
3893 The operand represents the offset at which the variable is within
3894 the thread local storage. */
3896 else if (data
+ 1 + addr_size
< end
3897 && (data
[0] == DW_OP_addr
3898 || (addr_size
== 4 && data
[0] == DW_OP_const4u
)
3899 || (addr_size
== 8 && data
[0] == DW_OP_const8u
))
3900 && data
[1 + addr_size
] == DW_OP_GNU_push_tls_address
3901 && piece_end_p (data
+ 2 + addr_size
, end
))
3904 offset
= extract_unsigned_integer (data
+ 1, addr_size
,
3905 gdbarch_byte_order (gdbarch
));
3907 fprintf_filtered (stream
,
3908 _("a thread-local variable at offset 0x%s "
3909 "in the thread-local storage for `%s'"),
3910 phex_nz (offset
, addr_size
), objfile_name (objfile
));
3912 data
+= 1 + addr_size
+ 1;
3915 /* With -gsplit-dwarf a TLS variable can also look like this:
3916 DW_AT_location : 3 byte block: fc 4 e0
3917 (DW_OP_GNU_const_index: 4;
3918 DW_OP_GNU_push_tls_address) */
3919 else if (data
+ 3 <= end
3920 && data
+ 1 + (leb128_size
= skip_leb128 (data
+ 1, end
)) < end
3921 && data
[0] == DW_OP_GNU_const_index
3923 && data
[1 + leb128_size
] == DW_OP_GNU_push_tls_address
3924 && piece_end_p (data
+ 2 + leb128_size
, end
))
3928 data
= safe_read_uleb128 (data
+ 1, end
, &offset
);
3929 offset
= dwarf2_read_addr_index (per_cu
, offset
);
3930 fprintf_filtered (stream
,
3931 _("a thread-local variable at offset 0x%s "
3932 "in the thread-local storage for `%s'"),
3933 phex_nz (offset
, addr_size
), objfile_name (objfile
));
3937 else if (data
[0] >= DW_OP_lit0
3938 && data
[0] <= DW_OP_lit31
3940 && data
[1] == DW_OP_stack_value
)
3942 fprintf_filtered (stream
, _("the constant %d"), data
[0] - DW_OP_lit0
);
3949 /* Disassemble an expression, stopping at the end of a piece or at the
3950 end of the expression. Returns a pointer to the next unread byte
3951 in the input expression. If ALL is nonzero, then this function
3952 will keep going until it reaches the end of the expression.
3953 If there is an error during reading, e.g. we run off the end
3954 of the buffer, an error is thrown. */
3956 static const gdb_byte
*
3957 disassemble_dwarf_expression (struct ui_file
*stream
,
3958 struct gdbarch
*arch
, unsigned int addr_size
,
3959 int offset_size
, const gdb_byte
*start
,
3960 const gdb_byte
*data
, const gdb_byte
*end
,
3961 int indent
, int all
,
3962 struct dwarf2_per_cu_data
*per_cu
)
3966 || (data
[0] != DW_OP_piece
&& data
[0] != DW_OP_bit_piece
)))
3968 enum dwarf_location_atom op
= (enum dwarf_location_atom
) *data
++;
3973 name
= get_DW_OP_name (op
);
3976 error (_("Unrecognized DWARF opcode 0x%02x at %ld"),
3977 op
, (long) (data
- 1 - start
));
3978 fprintf_filtered (stream
, " %*ld: %s", indent
+ 4,
3979 (long) (data
- 1 - start
), name
);
3984 ul
= extract_unsigned_integer (data
, addr_size
,
3985 gdbarch_byte_order (arch
));
3987 fprintf_filtered (stream
, " 0x%s", phex_nz (ul
, addr_size
));
3991 ul
= extract_unsigned_integer (data
, 1, gdbarch_byte_order (arch
));
3993 fprintf_filtered (stream
, " %s", pulongest (ul
));
3996 l
= extract_signed_integer (data
, 1, gdbarch_byte_order (arch
));
3998 fprintf_filtered (stream
, " %s", plongest (l
));
4001 ul
= extract_unsigned_integer (data
, 2, gdbarch_byte_order (arch
));
4003 fprintf_filtered (stream
, " %s", pulongest (ul
));
4006 l
= extract_signed_integer (data
, 2, gdbarch_byte_order (arch
));
4008 fprintf_filtered (stream
, " %s", plongest (l
));
4011 ul
= extract_unsigned_integer (data
, 4, gdbarch_byte_order (arch
));
4013 fprintf_filtered (stream
, " %s", pulongest (ul
));
4016 l
= extract_signed_integer (data
, 4, gdbarch_byte_order (arch
));
4018 fprintf_filtered (stream
, " %s", plongest (l
));
4021 ul
= extract_unsigned_integer (data
, 8, gdbarch_byte_order (arch
));
4023 fprintf_filtered (stream
, " %s", pulongest (ul
));
4026 l
= extract_signed_integer (data
, 8, gdbarch_byte_order (arch
));
4028 fprintf_filtered (stream
, " %s", plongest (l
));
4031 data
= safe_read_uleb128 (data
, end
, &ul
);
4032 fprintf_filtered (stream
, " %s", pulongest (ul
));
4035 data
= safe_read_sleb128 (data
, end
, &l
);
4036 fprintf_filtered (stream
, " %s", plongest (l
));
4071 fprintf_filtered (stream
, " [$%s]",
4072 locexpr_regname (arch
, op
- DW_OP_reg0
));
4076 data
= safe_read_uleb128 (data
, end
, &ul
);
4077 fprintf_filtered (stream
, " %s [$%s]", pulongest (ul
),
4078 locexpr_regname (arch
, (int) ul
));
4081 case DW_OP_implicit_value
:
4082 data
= safe_read_uleb128 (data
, end
, &ul
);
4084 fprintf_filtered (stream
, " %s", pulongest (ul
));
4119 data
= safe_read_sleb128 (data
, end
, &l
);
4120 fprintf_filtered (stream
, " %s [$%s]", plongest (l
),
4121 locexpr_regname (arch
, op
- DW_OP_breg0
));
4125 data
= safe_read_uleb128 (data
, end
, &ul
);
4126 data
= safe_read_sleb128 (data
, end
, &l
);
4127 fprintf_filtered (stream
, " register %s [$%s] offset %s",
4129 locexpr_regname (arch
, (int) ul
),
4134 data
= safe_read_sleb128 (data
, end
, &l
);
4135 fprintf_filtered (stream
, " %s", plongest (l
));
4138 case DW_OP_xderef_size
:
4139 case DW_OP_deref_size
:
4141 fprintf_filtered (stream
, " %d", *data
);
4145 case DW_OP_plus_uconst
:
4146 data
= safe_read_uleb128 (data
, end
, &ul
);
4147 fprintf_filtered (stream
, " %s", pulongest (ul
));
4151 l
= extract_signed_integer (data
, 2, gdbarch_byte_order (arch
));
4153 fprintf_filtered (stream
, " to %ld",
4154 (long) (data
+ l
- start
));
4158 l
= extract_signed_integer (data
, 2, gdbarch_byte_order (arch
));
4160 fprintf_filtered (stream
, " %ld",
4161 (long) (data
+ l
- start
));
4165 ul
= extract_unsigned_integer (data
, 2, gdbarch_byte_order (arch
));
4167 fprintf_filtered (stream
, " offset %s", phex_nz (ul
, 2));
4171 ul
= extract_unsigned_integer (data
, 4, gdbarch_byte_order (arch
));
4173 fprintf_filtered (stream
, " offset %s", phex_nz (ul
, 4));
4176 case DW_OP_call_ref
:
4177 ul
= extract_unsigned_integer (data
, offset_size
,
4178 gdbarch_byte_order (arch
));
4179 data
+= offset_size
;
4180 fprintf_filtered (stream
, " offset %s", phex_nz (ul
, offset_size
));
4184 data
= safe_read_uleb128 (data
, end
, &ul
);
4185 fprintf_filtered (stream
, " %s (bytes)", pulongest (ul
));
4188 case DW_OP_bit_piece
:
4192 data
= safe_read_uleb128 (data
, end
, &ul
);
4193 data
= safe_read_uleb128 (data
, end
, &offset
);
4194 fprintf_filtered (stream
, " size %s offset %s (bits)",
4195 pulongest (ul
), pulongest (offset
));
4199 case DW_OP_GNU_implicit_pointer
:
4201 ul
= extract_unsigned_integer (data
, offset_size
,
4202 gdbarch_byte_order (arch
));
4203 data
+= offset_size
;
4205 data
= safe_read_sleb128 (data
, end
, &l
);
4207 fprintf_filtered (stream
, " DIE %s offset %s",
4208 phex_nz (ul
, offset_size
),
4213 case DW_OP_GNU_deref_type
:
4215 int addr_size
= *data
++;
4219 data
= safe_read_uleb128 (data
, end
, &ul
);
4221 type
= dwarf2_get_die_type (offset
, per_cu
);
4222 fprintf_filtered (stream
, "<");
4223 type_print (type
, "", stream
, -1);
4224 fprintf_filtered (stream
, " [0x%s]> %d", phex_nz (offset
.cu_off
, 0),
4229 case DW_OP_GNU_const_type
:
4234 data
= safe_read_uleb128 (data
, end
, &ul
);
4235 type_die
.cu_off
= ul
;
4236 type
= dwarf2_get_die_type (type_die
, per_cu
);
4237 fprintf_filtered (stream
, "<");
4238 type_print (type
, "", stream
, -1);
4239 fprintf_filtered (stream
, " [0x%s]>", phex_nz (type_die
.cu_off
, 0));
4243 case DW_OP_GNU_regval_type
:
4249 data
= safe_read_uleb128 (data
, end
, ®
);
4250 data
= safe_read_uleb128 (data
, end
, &ul
);
4251 type_die
.cu_off
= ul
;
4253 type
= dwarf2_get_die_type (type_die
, per_cu
);
4254 fprintf_filtered (stream
, "<");
4255 type_print (type
, "", stream
, -1);
4256 fprintf_filtered (stream
, " [0x%s]> [$%s]",
4257 phex_nz (type_die
.cu_off
, 0),
4258 locexpr_regname (arch
, reg
));
4262 case DW_OP_GNU_convert
:
4263 case DW_OP_GNU_reinterpret
:
4267 data
= safe_read_uleb128 (data
, end
, &ul
);
4268 type_die
.cu_off
= ul
;
4270 if (type_die
.cu_off
== 0)
4271 fprintf_filtered (stream
, "<0>");
4276 type
= dwarf2_get_die_type (type_die
, per_cu
);
4277 fprintf_filtered (stream
, "<");
4278 type_print (type
, "", stream
, -1);
4279 fprintf_filtered (stream
, " [0x%s]>", phex_nz (type_die
.cu_off
, 0));
4284 case DW_OP_GNU_entry_value
:
4285 data
= safe_read_uleb128 (data
, end
, &ul
);
4286 fputc_filtered ('\n', stream
);
4287 disassemble_dwarf_expression (stream
, arch
, addr_size
, offset_size
,
4288 start
, data
, data
+ ul
, indent
+ 2,
4293 case DW_OP_GNU_parameter_ref
:
4294 ul
= extract_unsigned_integer (data
, 4, gdbarch_byte_order (arch
));
4296 fprintf_filtered (stream
, " offset %s", phex_nz (ul
, 4));
4299 case DW_OP_GNU_addr_index
:
4300 data
= safe_read_uleb128 (data
, end
, &ul
);
4301 ul
= dwarf2_read_addr_index (per_cu
, ul
);
4302 fprintf_filtered (stream
, " 0x%s", phex_nz (ul
, addr_size
));
4304 case DW_OP_GNU_const_index
:
4305 data
= safe_read_uleb128 (data
, end
, &ul
);
4306 ul
= dwarf2_read_addr_index (per_cu
, ul
);
4307 fprintf_filtered (stream
, " %s", pulongest (ul
));
4311 fprintf_filtered (stream
, "\n");
4317 /* Describe a single location, which may in turn consist of multiple
4321 locexpr_describe_location_1 (struct symbol
*symbol
, CORE_ADDR addr
,
4322 struct ui_file
*stream
,
4323 const gdb_byte
*data
, size_t size
,
4324 struct objfile
*objfile
, unsigned int addr_size
,
4325 int offset_size
, struct dwarf2_per_cu_data
*per_cu
)
4327 const gdb_byte
*end
= data
+ size
;
4328 int first_piece
= 1, bad
= 0;
4332 const gdb_byte
*here
= data
;
4333 int disassemble
= 1;
4338 fprintf_filtered (stream
, _(", and "));
4340 if (!dwarf_always_disassemble
)
4342 data
= locexpr_describe_location_piece (symbol
, stream
,
4343 addr
, objfile
, per_cu
,
4344 data
, end
, addr_size
);
4345 /* If we printed anything, or if we have an empty piece,
4346 then don't disassemble. */
4348 || data
[0] == DW_OP_piece
4349 || data
[0] == DW_OP_bit_piece
)
4354 fprintf_filtered (stream
, _("a complex DWARF expression:\n"));
4355 data
= disassemble_dwarf_expression (stream
,
4356 get_objfile_arch (objfile
),
4357 addr_size
, offset_size
, data
,
4359 dwarf_always_disassemble
,
4365 int empty
= data
== here
;
4368 fprintf_filtered (stream
, " ");
4369 if (data
[0] == DW_OP_piece
)
4373 data
= safe_read_uleb128 (data
+ 1, end
, &bytes
);
4376 fprintf_filtered (stream
, _("an empty %s-byte piece"),
4379 fprintf_filtered (stream
, _(" [%s-byte piece]"),
4382 else if (data
[0] == DW_OP_bit_piece
)
4384 uint64_t bits
, offset
;
4386 data
= safe_read_uleb128 (data
+ 1, end
, &bits
);
4387 data
= safe_read_uleb128 (data
, end
, &offset
);
4390 fprintf_filtered (stream
,
4391 _("an empty %s-bit piece"),
4394 fprintf_filtered (stream
,
4395 _(" [%s-bit piece, offset %s bits]"),
4396 pulongest (bits
), pulongest (offset
));
4406 if (bad
|| data
> end
)
4407 error (_("Corrupted DWARF2 expression for \"%s\"."),
4408 SYMBOL_PRINT_NAME (symbol
));
4411 /* Print a natural-language description of SYMBOL to STREAM. This
4412 version is for a symbol with a single location. */
4415 locexpr_describe_location (struct symbol
*symbol
, CORE_ADDR addr
,
4416 struct ui_file
*stream
)
4418 struct dwarf2_locexpr_baton
*dlbaton
4419 = (struct dwarf2_locexpr_baton
*) SYMBOL_LOCATION_BATON (symbol
);
4420 struct objfile
*objfile
= dwarf2_per_cu_objfile (dlbaton
->per_cu
);
4421 unsigned int addr_size
= dwarf2_per_cu_addr_size (dlbaton
->per_cu
);
4422 int offset_size
= dwarf2_per_cu_offset_size (dlbaton
->per_cu
);
4424 locexpr_describe_location_1 (symbol
, addr
, stream
,
4425 dlbaton
->data
, dlbaton
->size
,
4426 objfile
, addr_size
, offset_size
,
4430 /* Describe the location of SYMBOL as an agent value in VALUE, generating
4431 any necessary bytecode in AX. */
4434 locexpr_tracepoint_var_ref (struct symbol
*symbol
, struct gdbarch
*gdbarch
,
4435 struct agent_expr
*ax
, struct axs_value
*value
)
4437 struct dwarf2_locexpr_baton
*dlbaton
4438 = (struct dwarf2_locexpr_baton
*) SYMBOL_LOCATION_BATON (symbol
);
4439 unsigned int addr_size
= dwarf2_per_cu_addr_size (dlbaton
->per_cu
);
4441 if (dlbaton
->size
== 0)
4442 value
->optimized_out
= 1;
4444 dwarf2_compile_expr_to_ax (ax
, value
, gdbarch
, addr_size
,
4445 dlbaton
->data
, dlbaton
->data
+ dlbaton
->size
,
4449 /* symbol_computed_ops 'generate_c_location' method. */
4452 locexpr_generate_c_location (struct symbol
*sym
, struct ui_file
*stream
,
4453 struct gdbarch
*gdbarch
,
4454 unsigned char *registers_used
,
4455 CORE_ADDR pc
, const char *result_name
)
4457 struct dwarf2_locexpr_baton
*dlbaton
4458 = (struct dwarf2_locexpr_baton
*) SYMBOL_LOCATION_BATON (sym
);
4459 unsigned int addr_size
= dwarf2_per_cu_addr_size (dlbaton
->per_cu
);
4461 if (dlbaton
->size
== 0)
4462 error (_("symbol \"%s\" is optimized out"), SYMBOL_NATURAL_NAME (sym
));
4464 compile_dwarf_expr_to_c (stream
, result_name
,
4465 sym
, pc
, gdbarch
, registers_used
, addr_size
,
4466 dlbaton
->data
, dlbaton
->data
+ dlbaton
->size
,
4470 /* The set of location functions used with the DWARF-2 expression
4472 const struct symbol_computed_ops dwarf2_locexpr_funcs
= {
4473 locexpr_read_variable
,
4474 locexpr_read_variable_at_entry
,
4475 locexpr_read_needs_frame
,
4476 locexpr_describe_location
,
4477 0, /* location_has_loclist */
4478 locexpr_tracepoint_var_ref
,
4479 locexpr_generate_c_location
4483 /* Wrapper functions for location lists. These generally find
4484 the appropriate location expression and call something above. */
4486 /* Return the value of SYMBOL in FRAME using the DWARF-2 expression
4487 evaluator to calculate the location. */
4488 static struct value
*
4489 loclist_read_variable (struct symbol
*symbol
, struct frame_info
*frame
)
4491 struct dwarf2_loclist_baton
*dlbaton
4492 = (struct dwarf2_loclist_baton
*) SYMBOL_LOCATION_BATON (symbol
);
4494 const gdb_byte
*data
;
4496 CORE_ADDR pc
= frame
? get_frame_address_in_block (frame
) : 0;
4498 data
= dwarf2_find_location_expression (dlbaton
, &size
, pc
);
4499 val
= dwarf2_evaluate_loc_desc (SYMBOL_TYPE (symbol
), frame
, data
, size
,
4505 /* Read variable SYMBOL like loclist_read_variable at (callee) FRAME's function
4506 entry. SYMBOL should be a function parameter, otherwise NO_ENTRY_VALUE_ERROR
4509 Function always returns non-NULL value, it may be marked optimized out if
4510 inferior frame information is not available. It throws NO_ENTRY_VALUE_ERROR
4511 if it cannot resolve the parameter for any reason. */
4513 static struct value
*
4514 loclist_read_variable_at_entry (struct symbol
*symbol
, struct frame_info
*frame
)
4516 struct dwarf2_loclist_baton
*dlbaton
4517 = (struct dwarf2_loclist_baton
*) SYMBOL_LOCATION_BATON (symbol
);
4518 const gdb_byte
*data
;
4522 if (frame
== NULL
|| !get_frame_func_if_available (frame
, &pc
))
4523 return allocate_optimized_out_value (SYMBOL_TYPE (symbol
));
4525 data
= dwarf2_find_location_expression (dlbaton
, &size
, pc
);
4527 return allocate_optimized_out_value (SYMBOL_TYPE (symbol
));
4529 return value_of_dwarf_block_entry (SYMBOL_TYPE (symbol
), frame
, data
, size
);
4532 /* Return non-zero iff we need a frame to evaluate SYMBOL. */
4534 loclist_read_needs_frame (struct symbol
*symbol
)
4536 /* If there's a location list, then assume we need to have a frame
4537 to choose the appropriate location expression. With tracking of
4538 global variables this is not necessarily true, but such tracking
4539 is disabled in GCC at the moment until we figure out how to
4545 /* Print a natural-language description of SYMBOL to STREAM. This
4546 version applies when there is a list of different locations, each
4547 with a specified address range. */
4550 loclist_describe_location (struct symbol
*symbol
, CORE_ADDR addr
,
4551 struct ui_file
*stream
)
4553 struct dwarf2_loclist_baton
*dlbaton
4554 = (struct dwarf2_loclist_baton
*) SYMBOL_LOCATION_BATON (symbol
);
4555 const gdb_byte
*loc_ptr
, *buf_end
;
4556 struct objfile
*objfile
= dwarf2_per_cu_objfile (dlbaton
->per_cu
);
4557 struct gdbarch
*gdbarch
= get_objfile_arch (objfile
);
4558 enum bfd_endian byte_order
= gdbarch_byte_order (gdbarch
);
4559 unsigned int addr_size
= dwarf2_per_cu_addr_size (dlbaton
->per_cu
);
4560 int offset_size
= dwarf2_per_cu_offset_size (dlbaton
->per_cu
);
4561 int signed_addr_p
= bfd_get_sign_extend_vma (objfile
->obfd
);
4562 /* Adjust base_address for relocatable objects. */
4563 CORE_ADDR base_offset
= dwarf2_per_cu_text_offset (dlbaton
->per_cu
);
4564 CORE_ADDR base_address
= dlbaton
->base_address
+ base_offset
;
4567 loc_ptr
= dlbaton
->data
;
4568 buf_end
= dlbaton
->data
+ dlbaton
->size
;
4570 fprintf_filtered (stream
, _("multi-location:\n"));
4572 /* Iterate through locations until we run out. */
4575 CORE_ADDR low
= 0, high
= 0; /* init for gcc -Wall */
4577 enum debug_loc_kind kind
;
4578 const gdb_byte
*new_ptr
= NULL
; /* init for gcc -Wall */
4580 if (dlbaton
->from_dwo
)
4581 kind
= decode_debug_loc_dwo_addresses (dlbaton
->per_cu
,
4582 loc_ptr
, buf_end
, &new_ptr
,
4583 &low
, &high
, byte_order
);
4585 kind
= decode_debug_loc_addresses (loc_ptr
, buf_end
, &new_ptr
,
4587 byte_order
, addr_size
,
4592 case DEBUG_LOC_END_OF_LIST
:
4595 case DEBUG_LOC_BASE_ADDRESS
:
4596 base_address
= high
+ base_offset
;
4597 fprintf_filtered (stream
, _(" Base address %s"),
4598 paddress (gdbarch
, base_address
));
4600 case DEBUG_LOC_START_END
:
4601 case DEBUG_LOC_START_LENGTH
:
4603 case DEBUG_LOC_BUFFER_OVERFLOW
:
4604 case DEBUG_LOC_INVALID_ENTRY
:
4605 error (_("Corrupted DWARF expression for symbol \"%s\"."),
4606 SYMBOL_PRINT_NAME (symbol
));
4608 gdb_assert_not_reached ("bad debug_loc_kind");
4611 /* Otherwise, a location expression entry. */
4612 low
+= base_address
;
4613 high
+= base_address
;
4615 low
= gdbarch_adjust_dwarf2_addr (gdbarch
, low
);
4616 high
= gdbarch_adjust_dwarf2_addr (gdbarch
, high
);
4618 length
= extract_unsigned_integer (loc_ptr
, 2, byte_order
);
4621 /* (It would improve readability to print only the minimum
4622 necessary digits of the second number of the range.) */
4623 fprintf_filtered (stream
, _(" Range %s-%s: "),
4624 paddress (gdbarch
, low
), paddress (gdbarch
, high
));
4626 /* Now describe this particular location. */
4627 locexpr_describe_location_1 (symbol
, low
, stream
, loc_ptr
, length
,
4628 objfile
, addr_size
, offset_size
,
4631 fprintf_filtered (stream
, "\n");
4637 /* Describe the location of SYMBOL as an agent value in VALUE, generating
4638 any necessary bytecode in AX. */
4640 loclist_tracepoint_var_ref (struct symbol
*symbol
, struct gdbarch
*gdbarch
,
4641 struct agent_expr
*ax
, struct axs_value
*value
)
4643 struct dwarf2_loclist_baton
*dlbaton
4644 = (struct dwarf2_loclist_baton
*) SYMBOL_LOCATION_BATON (symbol
);
4645 const gdb_byte
*data
;
4647 unsigned int addr_size
= dwarf2_per_cu_addr_size (dlbaton
->per_cu
);
4649 data
= dwarf2_find_location_expression (dlbaton
, &size
, ax
->scope
);
4651 value
->optimized_out
= 1;
4653 dwarf2_compile_expr_to_ax (ax
, value
, gdbarch
, addr_size
, data
, data
+ size
,
4657 /* symbol_computed_ops 'generate_c_location' method. */
4660 loclist_generate_c_location (struct symbol
*sym
, struct ui_file
*stream
,
4661 struct gdbarch
*gdbarch
,
4662 unsigned char *registers_used
,
4663 CORE_ADDR pc
, const char *result_name
)
4665 struct dwarf2_loclist_baton
*dlbaton
4666 = (struct dwarf2_loclist_baton
*) SYMBOL_LOCATION_BATON (sym
);
4667 unsigned int addr_size
= dwarf2_per_cu_addr_size (dlbaton
->per_cu
);
4668 const gdb_byte
*data
;
4671 data
= dwarf2_find_location_expression (dlbaton
, &size
, pc
);
4673 error (_("symbol \"%s\" is optimized out"), SYMBOL_NATURAL_NAME (sym
));
4675 compile_dwarf_expr_to_c (stream
, result_name
,
4676 sym
, pc
, gdbarch
, registers_used
, addr_size
,
4681 /* The set of location functions used with the DWARF-2 expression
4682 evaluator and location lists. */
4683 const struct symbol_computed_ops dwarf2_loclist_funcs
= {
4684 loclist_read_variable
,
4685 loclist_read_variable_at_entry
,
4686 loclist_read_needs_frame
,
4687 loclist_describe_location
,
4688 1, /* location_has_loclist */
4689 loclist_tracepoint_var_ref
,
4690 loclist_generate_c_location
4693 /* Provide a prototype to silence -Wmissing-prototypes. */
4694 extern initialize_file_ftype _initialize_dwarf2loc
;
4697 _initialize_dwarf2loc (void)
4699 add_setshow_zuinteger_cmd ("entry-values", class_maintenance
,
4700 &entry_values_debug
,
4701 _("Set entry values and tail call frames "
4703 _("Show entry values and tail call frames "
4705 _("When non-zero, the process of determining "
4706 "parameter values from function entry point "
4707 "and tail call frames will be printed."),
4709 show_entry_values_debug
,
4710 &setdebuglist
, &showdebuglist
);