1 /* DWARF 2 location expression support for GDB.
3 Copyright (C) 2003-2017 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"
44 #include <unordered_set>
45 #include "common/underlying.h"
47 extern int dwarf_always_disassemble
;
49 static struct value
*dwarf2_evaluate_loc_desc_full (struct type
*type
,
50 struct frame_info
*frame
,
53 struct dwarf2_per_cu_data
*per_cu
,
54 struct type
*subobj_type
,
55 LONGEST subobj_byte_offset
);
57 static struct call_site_parameter
*dwarf_expr_reg_to_entry_parameter
58 (struct frame_info
*frame
,
59 enum call_site_parameter_kind kind
,
60 union call_site_parameter_u kind_u
,
61 struct dwarf2_per_cu_data
**per_cu_return
);
63 /* Until these have formal names, we define these here.
64 ref: http://gcc.gnu.org/wiki/DebugFission
65 Each entry in .debug_loc.dwo begins with a byte that describes the entry,
66 and is then followed by data specific to that entry. */
70 /* Indicates the end of the list of entries. */
71 DEBUG_LOC_END_OF_LIST
= 0,
73 /* This is followed by an unsigned LEB128 number that is an index into
74 .debug_addr and specifies the base address for all following entries. */
75 DEBUG_LOC_BASE_ADDRESS
= 1,
77 /* This is followed by two unsigned LEB128 numbers that are indices into
78 .debug_addr and specify the beginning and ending addresses, and then
79 a normal location expression as in .debug_loc. */
80 DEBUG_LOC_START_END
= 2,
82 /* This is followed by an unsigned LEB128 number that is an index into
83 .debug_addr and specifies the beginning address, and a 4 byte unsigned
84 number that specifies the length, and then a normal location expression
86 DEBUG_LOC_START_LENGTH
= 3,
88 /* An internal value indicating there is insufficient data. */
89 DEBUG_LOC_BUFFER_OVERFLOW
= -1,
91 /* An internal value indicating an invalid kind of entry was found. */
92 DEBUG_LOC_INVALID_ENTRY
= -2
95 /* Helper function which throws an error if a synthetic pointer is
99 invalid_synthetic_pointer (void)
101 error (_("access outside bounds of object "
102 "referenced via synthetic pointer"));
105 /* Decode the addresses in a non-dwo .debug_loc entry.
106 A pointer to the next byte to examine is returned in *NEW_PTR.
107 The encoded low,high addresses are return in *LOW,*HIGH.
108 The result indicates the kind of entry found. */
110 static enum debug_loc_kind
111 decode_debug_loc_addresses (const gdb_byte
*loc_ptr
, const gdb_byte
*buf_end
,
112 const gdb_byte
**new_ptr
,
113 CORE_ADDR
*low
, CORE_ADDR
*high
,
114 enum bfd_endian byte_order
,
115 unsigned int addr_size
,
118 CORE_ADDR base_mask
= ~(~(CORE_ADDR
)1 << (addr_size
* 8 - 1));
120 if (buf_end
- loc_ptr
< 2 * addr_size
)
121 return DEBUG_LOC_BUFFER_OVERFLOW
;
124 *low
= extract_signed_integer (loc_ptr
, addr_size
, byte_order
);
126 *low
= extract_unsigned_integer (loc_ptr
, addr_size
, byte_order
);
127 loc_ptr
+= addr_size
;
130 *high
= extract_signed_integer (loc_ptr
, addr_size
, byte_order
);
132 *high
= extract_unsigned_integer (loc_ptr
, addr_size
, byte_order
);
133 loc_ptr
+= addr_size
;
137 /* A base-address-selection entry. */
138 if ((*low
& base_mask
) == base_mask
)
139 return DEBUG_LOC_BASE_ADDRESS
;
141 /* An end-of-list entry. */
142 if (*low
== 0 && *high
== 0)
143 return DEBUG_LOC_END_OF_LIST
;
145 return DEBUG_LOC_START_END
;
148 /* Decode the addresses in .debug_loclists entry.
149 A pointer to the next byte to examine is returned in *NEW_PTR.
150 The encoded low,high addresses are return in *LOW,*HIGH.
151 The result indicates the kind of entry found. */
153 static enum debug_loc_kind
154 decode_debug_loclists_addresses (struct dwarf2_per_cu_data
*per_cu
,
155 const gdb_byte
*loc_ptr
,
156 const gdb_byte
*buf_end
,
157 const gdb_byte
**new_ptr
,
158 CORE_ADDR
*low
, CORE_ADDR
*high
,
159 enum bfd_endian byte_order
,
160 unsigned int addr_size
,
165 if (loc_ptr
== buf_end
)
166 return DEBUG_LOC_BUFFER_OVERFLOW
;
170 case DW_LLE_end_of_list
:
172 return DEBUG_LOC_END_OF_LIST
;
173 case DW_LLE_base_address
:
174 if (loc_ptr
+ addr_size
> buf_end
)
175 return DEBUG_LOC_BUFFER_OVERFLOW
;
177 *high
= extract_signed_integer (loc_ptr
, addr_size
, byte_order
);
179 *high
= extract_unsigned_integer (loc_ptr
, addr_size
, byte_order
);
180 loc_ptr
+= addr_size
;
182 return DEBUG_LOC_BASE_ADDRESS
;
183 case DW_LLE_offset_pair
:
184 loc_ptr
= gdb_read_uleb128 (loc_ptr
, buf_end
, &u64
);
186 return DEBUG_LOC_BUFFER_OVERFLOW
;
188 loc_ptr
= gdb_read_uleb128 (loc_ptr
, buf_end
, &u64
);
190 return DEBUG_LOC_BUFFER_OVERFLOW
;
193 return DEBUG_LOC_START_END
;
195 return DEBUG_LOC_INVALID_ENTRY
;
199 /* Decode the addresses in .debug_loc.dwo entry.
200 A pointer to the next byte to examine is returned in *NEW_PTR.
201 The encoded low,high addresses are return in *LOW,*HIGH.
202 The result indicates the kind of entry found. */
204 static enum debug_loc_kind
205 decode_debug_loc_dwo_addresses (struct dwarf2_per_cu_data
*per_cu
,
206 const gdb_byte
*loc_ptr
,
207 const gdb_byte
*buf_end
,
208 const gdb_byte
**new_ptr
,
209 CORE_ADDR
*low
, CORE_ADDR
*high
,
210 enum bfd_endian byte_order
)
212 uint64_t low_index
, high_index
;
214 if (loc_ptr
== buf_end
)
215 return DEBUG_LOC_BUFFER_OVERFLOW
;
219 case DW_LLE_GNU_end_of_list_entry
:
221 return DEBUG_LOC_END_OF_LIST
;
222 case DW_LLE_GNU_base_address_selection_entry
:
224 loc_ptr
= gdb_read_uleb128 (loc_ptr
, buf_end
, &high_index
);
226 return DEBUG_LOC_BUFFER_OVERFLOW
;
227 *high
= dwarf2_read_addr_index (per_cu
, high_index
);
229 return DEBUG_LOC_BASE_ADDRESS
;
230 case DW_LLE_GNU_start_end_entry
:
231 loc_ptr
= gdb_read_uleb128 (loc_ptr
, buf_end
, &low_index
);
233 return DEBUG_LOC_BUFFER_OVERFLOW
;
234 *low
= dwarf2_read_addr_index (per_cu
, low_index
);
235 loc_ptr
= gdb_read_uleb128 (loc_ptr
, buf_end
, &high_index
);
237 return DEBUG_LOC_BUFFER_OVERFLOW
;
238 *high
= dwarf2_read_addr_index (per_cu
, high_index
);
240 return DEBUG_LOC_START_END
;
241 case DW_LLE_GNU_start_length_entry
:
242 loc_ptr
= gdb_read_uleb128 (loc_ptr
, buf_end
, &low_index
);
244 return DEBUG_LOC_BUFFER_OVERFLOW
;
245 *low
= dwarf2_read_addr_index (per_cu
, low_index
);
246 if (loc_ptr
+ 4 > buf_end
)
247 return DEBUG_LOC_BUFFER_OVERFLOW
;
249 *high
+= extract_unsigned_integer (loc_ptr
, 4, byte_order
);
250 *new_ptr
= loc_ptr
+ 4;
251 return DEBUG_LOC_START_LENGTH
;
253 return DEBUG_LOC_INVALID_ENTRY
;
257 /* A function for dealing with location lists. Given a
258 symbol baton (BATON) and a pc value (PC), find the appropriate
259 location expression, set *LOCEXPR_LENGTH, and return a pointer
260 to the beginning of the expression. Returns NULL on failure.
262 For now, only return the first matching location expression; there
263 can be more than one in the list. */
266 dwarf2_find_location_expression (struct dwarf2_loclist_baton
*baton
,
267 size_t *locexpr_length
, CORE_ADDR pc
)
269 struct objfile
*objfile
= dwarf2_per_cu_objfile (baton
->per_cu
);
270 struct gdbarch
*gdbarch
= get_objfile_arch (objfile
);
271 enum bfd_endian byte_order
= gdbarch_byte_order (gdbarch
);
272 unsigned int addr_size
= dwarf2_per_cu_addr_size (baton
->per_cu
);
273 int signed_addr_p
= bfd_get_sign_extend_vma (objfile
->obfd
);
274 /* Adjust base_address for relocatable objects. */
275 CORE_ADDR base_offset
= dwarf2_per_cu_text_offset (baton
->per_cu
);
276 CORE_ADDR base_address
= baton
->base_address
+ base_offset
;
277 const gdb_byte
*loc_ptr
, *buf_end
;
279 loc_ptr
= baton
->data
;
280 buf_end
= baton
->data
+ baton
->size
;
284 CORE_ADDR low
= 0, high
= 0; /* init for gcc -Wall */
286 enum debug_loc_kind kind
;
287 const gdb_byte
*new_ptr
= NULL
; /* init for gcc -Wall */
290 kind
= decode_debug_loc_dwo_addresses (baton
->per_cu
,
291 loc_ptr
, buf_end
, &new_ptr
,
292 &low
, &high
, byte_order
);
293 else if (dwarf2_version (baton
->per_cu
) < 5)
294 kind
= decode_debug_loc_addresses (loc_ptr
, buf_end
, &new_ptr
,
296 byte_order
, addr_size
,
299 kind
= decode_debug_loclists_addresses (baton
->per_cu
,
300 loc_ptr
, buf_end
, &new_ptr
,
301 &low
, &high
, byte_order
,
302 addr_size
, signed_addr_p
);
307 case DEBUG_LOC_END_OF_LIST
:
310 case DEBUG_LOC_BASE_ADDRESS
:
311 base_address
= high
+ base_offset
;
313 case DEBUG_LOC_START_END
:
314 case DEBUG_LOC_START_LENGTH
:
316 case DEBUG_LOC_BUFFER_OVERFLOW
:
317 case DEBUG_LOC_INVALID_ENTRY
:
318 error (_("dwarf2_find_location_expression: "
319 "Corrupted DWARF expression."));
321 gdb_assert_not_reached ("bad debug_loc_kind");
324 /* Otherwise, a location expression entry.
325 If the entry is from a DWO, don't add base address: the entry is from
326 .debug_addr which already has the DWARF "base address". We still add
327 base_offset in case we're debugging a PIE executable. */
336 high
+= base_address
;
339 if (dwarf2_version (baton
->per_cu
) < 5)
341 length
= extract_unsigned_integer (loc_ptr
, 2, byte_order
);
346 unsigned int bytes_read
;
348 length
= read_unsigned_leb128 (NULL
, loc_ptr
, &bytes_read
);
349 loc_ptr
+= bytes_read
;
352 if (low
== high
&& pc
== low
)
354 /* This is entry PC record present only at entry point
355 of a function. Verify it is really the function entry point. */
357 const struct block
*pc_block
= block_for_pc (pc
);
358 struct symbol
*pc_func
= NULL
;
361 pc_func
= block_linkage_function (pc_block
);
363 if (pc_func
&& pc
== BLOCK_START (SYMBOL_BLOCK_VALUE (pc_func
)))
365 *locexpr_length
= length
;
370 if (pc
>= low
&& pc
< high
)
372 *locexpr_length
= length
;
380 /* This is the baton used when performing dwarf2 expression
382 struct dwarf_expr_baton
384 struct frame_info
*frame
;
385 struct dwarf2_per_cu_data
*per_cu
;
386 CORE_ADDR obj_address
;
389 /* Implement find_frame_base_location method for LOC_BLOCK functions using
390 DWARF expression for its DW_AT_frame_base. */
393 locexpr_find_frame_base_location (struct symbol
*framefunc
, CORE_ADDR pc
,
394 const gdb_byte
**start
, size_t *length
)
396 struct dwarf2_locexpr_baton
*symbaton
397 = (struct dwarf2_locexpr_baton
*) SYMBOL_LOCATION_BATON (framefunc
);
399 *length
= symbaton
->size
;
400 *start
= symbaton
->data
;
403 /* Implement the struct symbol_block_ops::get_frame_base method for
404 LOC_BLOCK functions using a DWARF expression as its DW_AT_frame_base. */
407 locexpr_get_frame_base (struct symbol
*framefunc
, struct frame_info
*frame
)
409 struct gdbarch
*gdbarch
;
411 struct dwarf2_locexpr_baton
*dlbaton
;
412 const gdb_byte
*start
;
414 struct value
*result
;
416 /* If this method is called, then FRAMEFUNC is supposed to be a DWARF block.
417 Thus, it's supposed to provide the find_frame_base_location method as
419 gdb_assert (SYMBOL_BLOCK_OPS (framefunc
)->find_frame_base_location
!= NULL
);
421 gdbarch
= get_frame_arch (frame
);
422 type
= builtin_type (gdbarch
)->builtin_data_ptr
;
423 dlbaton
= (struct dwarf2_locexpr_baton
*) SYMBOL_LOCATION_BATON (framefunc
);
425 SYMBOL_BLOCK_OPS (framefunc
)->find_frame_base_location
426 (framefunc
, get_frame_pc (frame
), &start
, &length
);
427 result
= dwarf2_evaluate_loc_desc (type
, frame
, start
, length
,
430 /* The DW_AT_frame_base attribute contains a location description which
431 computes the base address itself. However, the call to
432 dwarf2_evaluate_loc_desc returns a value representing a variable at
433 that address. The frame base address is thus this variable's
435 return value_address (result
);
438 /* Vector for inferior functions as represented by LOC_BLOCK, if the inferior
439 function uses DWARF expression for its DW_AT_frame_base. */
441 const struct symbol_block_ops dwarf2_block_frame_base_locexpr_funcs
=
443 locexpr_find_frame_base_location
,
444 locexpr_get_frame_base
447 /* Implement find_frame_base_location method for LOC_BLOCK functions using
448 DWARF location list for its DW_AT_frame_base. */
451 loclist_find_frame_base_location (struct symbol
*framefunc
, CORE_ADDR pc
,
452 const gdb_byte
**start
, size_t *length
)
454 struct dwarf2_loclist_baton
*symbaton
455 = (struct dwarf2_loclist_baton
*) SYMBOL_LOCATION_BATON (framefunc
);
457 *start
= dwarf2_find_location_expression (symbaton
, length
, pc
);
460 /* Implement the struct symbol_block_ops::get_frame_base method for
461 LOC_BLOCK functions using a DWARF location list as its DW_AT_frame_base. */
464 loclist_get_frame_base (struct symbol
*framefunc
, struct frame_info
*frame
)
466 struct gdbarch
*gdbarch
;
468 struct dwarf2_loclist_baton
*dlbaton
;
469 const gdb_byte
*start
;
471 struct value
*result
;
473 /* If this method is called, then FRAMEFUNC is supposed to be a DWARF block.
474 Thus, it's supposed to provide the find_frame_base_location method as
476 gdb_assert (SYMBOL_BLOCK_OPS (framefunc
)->find_frame_base_location
!= NULL
);
478 gdbarch
= get_frame_arch (frame
);
479 type
= builtin_type (gdbarch
)->builtin_data_ptr
;
480 dlbaton
= (struct dwarf2_loclist_baton
*) SYMBOL_LOCATION_BATON (framefunc
);
482 SYMBOL_BLOCK_OPS (framefunc
)->find_frame_base_location
483 (framefunc
, get_frame_pc (frame
), &start
, &length
);
484 result
= dwarf2_evaluate_loc_desc (type
, frame
, start
, length
,
487 /* The DW_AT_frame_base attribute contains a location description which
488 computes the base address itself. However, the call to
489 dwarf2_evaluate_loc_desc returns a value representing a variable at
490 that address. The frame base address is thus this variable's
492 return value_address (result
);
495 /* Vector for inferior functions as represented by LOC_BLOCK, if the inferior
496 function uses DWARF location list for its DW_AT_frame_base. */
498 const struct symbol_block_ops dwarf2_block_frame_base_loclist_funcs
=
500 loclist_find_frame_base_location
,
501 loclist_get_frame_base
504 /* See dwarf2loc.h. */
507 func_get_frame_base_dwarf_block (struct symbol
*framefunc
, CORE_ADDR pc
,
508 const gdb_byte
**start
, size_t *length
)
510 if (SYMBOL_BLOCK_OPS (framefunc
) != NULL
)
512 const struct symbol_block_ops
*ops_block
= SYMBOL_BLOCK_OPS (framefunc
);
514 ops_block
->find_frame_base_location (framefunc
, pc
, start
, length
);
520 error (_("Could not find the frame base for \"%s\"."),
521 SYMBOL_NATURAL_NAME (framefunc
));
525 get_frame_pc_for_per_cu_dwarf_call (void *baton
)
527 dwarf_expr_context
*ctx
= (dwarf_expr_context
*) baton
;
529 return ctx
->get_frame_pc ();
533 per_cu_dwarf_call (struct dwarf_expr_context
*ctx
, cu_offset die_offset
,
534 struct dwarf2_per_cu_data
*per_cu
)
536 struct dwarf2_locexpr_baton block
;
538 block
= dwarf2_fetch_die_loc_cu_off (die_offset
, per_cu
,
539 get_frame_pc_for_per_cu_dwarf_call
,
542 /* DW_OP_call_ref is currently not supported. */
543 gdb_assert (block
.per_cu
== per_cu
);
545 ctx
->eval (block
.data
, block
.size
);
548 class dwarf_evaluate_loc_desc
: public dwarf_expr_context
552 struct frame_info
*frame
;
553 struct dwarf2_per_cu_data
*per_cu
;
554 CORE_ADDR obj_address
;
556 /* Helper function for dwarf2_evaluate_loc_desc. Computes the CFA for
557 the frame in BATON. */
559 CORE_ADDR
get_frame_cfa () OVERRIDE
561 return dwarf2_frame_cfa (frame
);
564 /* Helper function for dwarf2_evaluate_loc_desc. Computes the PC for
565 the frame in BATON. */
567 CORE_ADDR
get_frame_pc () OVERRIDE
569 return get_frame_address_in_block (frame
);
572 /* Using the objfile specified in BATON, find the address for the
573 current thread's thread-local storage with offset OFFSET. */
574 CORE_ADDR
get_tls_address (CORE_ADDR offset
) OVERRIDE
576 struct objfile
*objfile
= dwarf2_per_cu_objfile (per_cu
);
578 return target_translate_tls_address (objfile
, offset
);
581 /* Helper interface of per_cu_dwarf_call for
582 dwarf2_evaluate_loc_desc. */
584 void dwarf_call (cu_offset die_offset
) OVERRIDE
586 per_cu_dwarf_call (this, die_offset
, per_cu
);
589 struct type
*get_base_type (cu_offset die_offset
, int size
) OVERRIDE
591 struct type
*result
= dwarf2_get_die_type (die_offset
, per_cu
);
593 error (_("Could not find type for DW_OP_const_type"));
594 if (size
!= 0 && TYPE_LENGTH (result
) != size
)
595 error (_("DW_OP_const_type has different sizes for type and data"));
599 /* Callback function for dwarf2_evaluate_loc_desc.
600 Fetch the address indexed by DW_OP_GNU_addr_index. */
602 CORE_ADDR
get_addr_index (unsigned int index
) OVERRIDE
604 return dwarf2_read_addr_index (per_cu
, index
);
607 /* Callback function for get_object_address. Return the address of the VLA
610 CORE_ADDR
get_object_address () OVERRIDE
612 if (obj_address
== 0)
613 error (_("Location address is not set."));
617 /* Execute DWARF block of call_site_parameter which matches KIND and
618 KIND_U. Choose DEREF_SIZE value of that parameter. Search
619 caller of this objects's frame.
621 The caller can be from a different CU - per_cu_dwarf_call
622 implementation can be more simple as it does not support cross-CU
625 void push_dwarf_reg_entry_value (enum call_site_parameter_kind kind
,
626 union call_site_parameter_u kind_u
,
627 int deref_size
) OVERRIDE
629 struct frame_info
*caller_frame
;
630 struct dwarf2_per_cu_data
*caller_per_cu
;
631 struct call_site_parameter
*parameter
;
632 const gdb_byte
*data_src
;
635 caller_frame
= get_prev_frame (frame
);
637 parameter
= dwarf_expr_reg_to_entry_parameter (frame
, kind
, kind_u
,
639 data_src
= deref_size
== -1 ? parameter
->value
: parameter
->data_value
;
640 size
= deref_size
== -1 ? parameter
->value_size
: parameter
->data_value_size
;
642 /* DEREF_SIZE size is not verified here. */
643 if (data_src
== NULL
)
644 throw_error (NO_ENTRY_VALUE_ERROR
,
645 _("Cannot resolve DW_AT_call_data_value"));
647 scoped_restore save_frame
= make_scoped_restore (&this->frame
,
649 scoped_restore save_per_cu
= make_scoped_restore (&this->per_cu
,
651 scoped_restore save_obj_addr
= make_scoped_restore (&this->obj_address
,
654 scoped_restore save_arch
= make_scoped_restore (&this->gdbarch
);
656 = get_objfile_arch (dwarf2_per_cu_objfile (per_cu
));
657 scoped_restore save_addr_size
= make_scoped_restore (&this->addr_size
);
658 this->addr_size
= dwarf2_per_cu_addr_size (per_cu
);
659 scoped_restore save_offset
= make_scoped_restore (&this->offset
);
660 this->offset
= dwarf2_per_cu_text_offset (per_cu
);
662 this->eval (data_src
, size
);
665 /* Using the frame specified in BATON, find the location expression
666 describing the frame base. Return a pointer to it in START and
667 its length in LENGTH. */
668 void get_frame_base (const gdb_byte
**start
, size_t * length
) OVERRIDE
670 /* FIXME: cagney/2003-03-26: This code should be using
671 get_frame_base_address(), and then implement a dwarf2 specific
673 struct symbol
*framefunc
;
674 const struct block
*bl
= get_frame_block (frame
, NULL
);
677 error (_("frame address is not available."));
679 /* Use block_linkage_function, which returns a real (not inlined)
680 function, instead of get_frame_function, which may return an
682 framefunc
= block_linkage_function (bl
);
684 /* If we found a frame-relative symbol then it was certainly within
685 some function associated with a frame. If we can't find the frame,
686 something has gone wrong. */
687 gdb_assert (framefunc
!= NULL
);
689 func_get_frame_base_dwarf_block (framefunc
,
690 get_frame_address_in_block (frame
),
694 /* Read memory at ADDR (length LEN) into BUF. */
696 void read_mem (gdb_byte
*buf
, CORE_ADDR addr
, size_t len
) OVERRIDE
698 read_memory (addr
, buf
, len
);
701 /* Using the frame specified in BATON, return the value of register
702 REGNUM, treated as a pointer. */
703 CORE_ADDR
read_addr_from_reg (int dwarf_regnum
) OVERRIDE
705 struct gdbarch
*gdbarch
= get_frame_arch (frame
);
706 int regnum
= dwarf_reg_to_regnum_or_error (gdbarch
, dwarf_regnum
);
708 return address_from_register (regnum
, frame
);
711 /* Implement "get_reg_value" callback. */
713 struct value
*get_reg_value (struct type
*type
, int dwarf_regnum
) OVERRIDE
715 struct gdbarch
*gdbarch
= get_frame_arch (frame
);
716 int regnum
= dwarf_reg_to_regnum_or_error (gdbarch
, dwarf_regnum
);
718 return value_from_register (type
, regnum
, frame
);
722 /* See dwarf2loc.h. */
724 unsigned int entry_values_debug
= 0;
726 /* Helper to set entry_values_debug. */
729 show_entry_values_debug (struct ui_file
*file
, int from_tty
,
730 struct cmd_list_element
*c
, const char *value
)
732 fprintf_filtered (file
,
733 _("Entry values and tail call frames debugging is %s.\n"),
737 /* Find DW_TAG_call_site's DW_AT_call_target address.
738 CALLER_FRAME (for registers) can be NULL if it is not known. This function
739 always returns valid address or it throws NO_ENTRY_VALUE_ERROR. */
742 call_site_to_target_addr (struct gdbarch
*call_site_gdbarch
,
743 struct call_site
*call_site
,
744 struct frame_info
*caller_frame
)
746 switch (FIELD_LOC_KIND (call_site
->target
))
748 case FIELD_LOC_KIND_DWARF_BLOCK
:
750 struct dwarf2_locexpr_baton
*dwarf_block
;
752 struct type
*caller_core_addr_type
;
753 struct gdbarch
*caller_arch
;
755 dwarf_block
= FIELD_DWARF_BLOCK (call_site
->target
);
756 if (dwarf_block
== NULL
)
758 struct bound_minimal_symbol msym
;
760 msym
= lookup_minimal_symbol_by_pc (call_site
->pc
- 1);
761 throw_error (NO_ENTRY_VALUE_ERROR
,
762 _("DW_AT_call_target is not specified at %s in %s"),
763 paddress (call_site_gdbarch
, call_site
->pc
),
764 (msym
.minsym
== NULL
? "???"
765 : MSYMBOL_PRINT_NAME (msym
.minsym
)));
768 if (caller_frame
== NULL
)
770 struct bound_minimal_symbol msym
;
772 msym
= lookup_minimal_symbol_by_pc (call_site
->pc
- 1);
773 throw_error (NO_ENTRY_VALUE_ERROR
,
774 _("DW_AT_call_target DWARF block resolving "
775 "requires known frame which is currently not "
776 "available at %s in %s"),
777 paddress (call_site_gdbarch
, call_site
->pc
),
778 (msym
.minsym
== NULL
? "???"
779 : MSYMBOL_PRINT_NAME (msym
.minsym
)));
782 caller_arch
= get_frame_arch (caller_frame
);
783 caller_core_addr_type
= builtin_type (caller_arch
)->builtin_func_ptr
;
784 val
= dwarf2_evaluate_loc_desc (caller_core_addr_type
, caller_frame
,
785 dwarf_block
->data
, dwarf_block
->size
,
786 dwarf_block
->per_cu
);
787 /* DW_AT_call_target is a DWARF expression, not a DWARF location. */
788 if (VALUE_LVAL (val
) == lval_memory
)
789 return value_address (val
);
791 return value_as_address (val
);
794 case FIELD_LOC_KIND_PHYSNAME
:
796 const char *physname
;
797 struct bound_minimal_symbol msym
;
799 physname
= FIELD_STATIC_PHYSNAME (call_site
->target
);
801 /* Handle both the mangled and demangled PHYSNAME. */
802 msym
= lookup_minimal_symbol (physname
, NULL
, NULL
);
803 if (msym
.minsym
== NULL
)
805 msym
= lookup_minimal_symbol_by_pc (call_site
->pc
- 1);
806 throw_error (NO_ENTRY_VALUE_ERROR
,
807 _("Cannot find function \"%s\" for a call site target "
809 physname
, paddress (call_site_gdbarch
, call_site
->pc
),
810 (msym
.minsym
== NULL
? "???"
811 : MSYMBOL_PRINT_NAME (msym
.minsym
)));
814 return BMSYMBOL_VALUE_ADDRESS (msym
);
817 case FIELD_LOC_KIND_PHYSADDR
:
818 return FIELD_STATIC_PHYSADDR (call_site
->target
);
821 internal_error (__FILE__
, __LINE__
, _("invalid call site target kind"));
825 /* Convert function entry point exact address ADDR to the function which is
826 compliant with TAIL_CALL_LIST_COMPLETE condition. Throw
827 NO_ENTRY_VALUE_ERROR otherwise. */
829 static struct symbol
*
830 func_addr_to_tail_call_list (struct gdbarch
*gdbarch
, CORE_ADDR addr
)
832 struct symbol
*sym
= find_pc_function (addr
);
835 if (sym
== NULL
|| BLOCK_START (SYMBOL_BLOCK_VALUE (sym
)) != addr
)
836 throw_error (NO_ENTRY_VALUE_ERROR
,
837 _("DW_TAG_call_site resolving failed to find function "
838 "name for address %s"),
839 paddress (gdbarch
, addr
));
841 type
= SYMBOL_TYPE (sym
);
842 gdb_assert (TYPE_CODE (type
) == TYPE_CODE_FUNC
);
843 gdb_assert (TYPE_SPECIFIC_FIELD (type
) == TYPE_SPECIFIC_FUNC
);
848 /* Verify function with entry point exact address ADDR can never call itself
849 via its tail calls (incl. transitively). Throw NO_ENTRY_VALUE_ERROR if it
850 can call itself via tail calls.
852 If a funtion can tail call itself its entry value based parameters are
853 unreliable. There is no verification whether the value of some/all
854 parameters is unchanged through the self tail call, we expect if there is
855 a self tail call all the parameters can be modified. */
858 func_verify_no_selftailcall (struct gdbarch
*gdbarch
, CORE_ADDR verify_addr
)
862 /* The verification is completely unordered. Track here function addresses
863 which still need to be iterated. */
864 std::vector
<CORE_ADDR
> todo
;
866 /* Track here CORE_ADDRs which were already visited. */
867 std::unordered_set
<CORE_ADDR
> addr_hash
;
869 todo
.push_back (verify_addr
);
870 while (!todo
.empty ())
872 struct symbol
*func_sym
;
873 struct call_site
*call_site
;
878 func_sym
= func_addr_to_tail_call_list (gdbarch
, addr
);
880 for (call_site
= TYPE_TAIL_CALL_LIST (SYMBOL_TYPE (func_sym
));
881 call_site
; call_site
= call_site
->tail_call_next
)
883 CORE_ADDR target_addr
;
885 /* CALLER_FRAME with registers is not available for tail-call jumped
887 target_addr
= call_site_to_target_addr (gdbarch
, call_site
, NULL
);
889 if (target_addr
== verify_addr
)
891 struct bound_minimal_symbol msym
;
893 msym
= lookup_minimal_symbol_by_pc (verify_addr
);
894 throw_error (NO_ENTRY_VALUE_ERROR
,
895 _("DW_OP_entry_value resolving has found "
896 "function \"%s\" at %s can call itself via tail "
898 (msym
.minsym
== NULL
? "???"
899 : MSYMBOL_PRINT_NAME (msym
.minsym
)),
900 paddress (gdbarch
, verify_addr
));
903 if (addr_hash
.insert (target_addr
).second
)
904 todo
.push_back (target_addr
);
909 /* Print user readable form of CALL_SITE->PC to gdb_stdlog. Used only for
910 ENTRY_VALUES_DEBUG. */
913 tailcall_dump (struct gdbarch
*gdbarch
, const struct call_site
*call_site
)
915 CORE_ADDR addr
= call_site
->pc
;
916 struct bound_minimal_symbol msym
= lookup_minimal_symbol_by_pc (addr
- 1);
918 fprintf_unfiltered (gdb_stdlog
, " %s(%s)", paddress (gdbarch
, addr
),
919 (msym
.minsym
== NULL
? "???"
920 : MSYMBOL_PRINT_NAME (msym
.minsym
)));
924 /* Intersect RESULTP with CHAIN to keep RESULTP unambiguous, keep in RESULTP
925 only top callers and bottom callees which are present in both. GDBARCH is
926 used only for ENTRY_VALUES_DEBUG. RESULTP is NULL after return if there are
927 no remaining possibilities to provide unambiguous non-trivial result.
928 RESULTP should point to NULL on the first (initialization) call. Caller is
929 responsible for xfree of any RESULTP data. */
932 chain_candidate (struct gdbarch
*gdbarch
,
933 gdb::unique_xmalloc_ptr
<struct call_site_chain
> *resultp
,
934 std::vector
<struct call_site
*> *chain
)
936 long length
= chain
->size ();
937 int callers
, callees
, idx
;
939 if (*resultp
== NULL
)
941 /* Create the initial chain containing all the passed PCs. */
943 struct call_site_chain
*result
944 = ((struct call_site_chain
*)
945 xmalloc (sizeof (*result
)
946 + sizeof (*result
->call_site
) * (length
- 1)));
947 result
->length
= length
;
948 result
->callers
= result
->callees
= length
;
949 if (!chain
->empty ())
950 memcpy (result
->call_site
, chain
->data (),
951 sizeof (*result
->call_site
) * length
);
952 resultp
->reset (result
);
954 if (entry_values_debug
)
956 fprintf_unfiltered (gdb_stdlog
, "tailcall: initial:");
957 for (idx
= 0; idx
< length
; idx
++)
958 tailcall_dump (gdbarch
, result
->call_site
[idx
]);
959 fputc_unfiltered ('\n', gdb_stdlog
);
965 if (entry_values_debug
)
967 fprintf_unfiltered (gdb_stdlog
, "tailcall: compare:");
968 for (idx
= 0; idx
< length
; idx
++)
969 tailcall_dump (gdbarch
, chain
->at (idx
));
970 fputc_unfiltered ('\n', gdb_stdlog
);
973 /* Intersect callers. */
975 callers
= std::min ((long) (*resultp
)->callers
, length
);
976 for (idx
= 0; idx
< callers
; idx
++)
977 if ((*resultp
)->call_site
[idx
] != chain
->at (idx
))
979 (*resultp
)->callers
= idx
;
983 /* Intersect callees. */
985 callees
= std::min ((long) (*resultp
)->callees
, length
);
986 for (idx
= 0; idx
< callees
; idx
++)
987 if ((*resultp
)->call_site
[(*resultp
)->length
- 1 - idx
]
988 != chain
->at (length
- 1 - idx
))
990 (*resultp
)->callees
= idx
;
994 if (entry_values_debug
)
996 fprintf_unfiltered (gdb_stdlog
, "tailcall: reduced:");
997 for (idx
= 0; idx
< (*resultp
)->callers
; idx
++)
998 tailcall_dump (gdbarch
, (*resultp
)->call_site
[idx
]);
999 fputs_unfiltered (" |", gdb_stdlog
);
1000 for (idx
= 0; idx
< (*resultp
)->callees
; idx
++)
1001 tailcall_dump (gdbarch
,
1002 (*resultp
)->call_site
[(*resultp
)->length
1003 - (*resultp
)->callees
+ idx
]);
1004 fputc_unfiltered ('\n', gdb_stdlog
);
1007 if ((*resultp
)->callers
== 0 && (*resultp
)->callees
== 0)
1009 /* There are no common callers or callees. It could be also a direct
1010 call (which has length 0) with ambiguous possibility of an indirect
1011 call - CALLERS == CALLEES == 0 is valid during the first allocation
1012 but any subsequence processing of such entry means ambiguity. */
1013 resultp
->reset (NULL
);
1017 /* See call_site_find_chain_1 why there is no way to reach the bottom callee
1018 PC again. In such case there must be two different code paths to reach
1019 it. CALLERS + CALLEES equal to LENGTH in the case of self tail-call. */
1020 gdb_assert ((*resultp
)->callers
+ (*resultp
)->callees
<= (*resultp
)->length
);
1023 /* Create and return call_site_chain for CALLER_PC and CALLEE_PC. All the
1024 assumed frames between them use GDBARCH. Use depth first search so we can
1025 keep single CHAIN of call_site's back to CALLER_PC. Function recursion
1026 would have needless GDB stack overhead. Caller is responsible for xfree of
1027 the returned result. Any unreliability results in thrown
1028 NO_ENTRY_VALUE_ERROR. */
1030 static struct call_site_chain
*
1031 call_site_find_chain_1 (struct gdbarch
*gdbarch
, CORE_ADDR caller_pc
,
1032 CORE_ADDR callee_pc
)
1034 CORE_ADDR save_callee_pc
= callee_pc
;
1035 gdb::unique_xmalloc_ptr
<struct call_site_chain
> retval
;
1036 struct call_site
*call_site
;
1038 /* CHAIN contains only the intermediate CALL_SITEs. Neither CALLER_PC's
1039 call_site nor any possible call_site at CALLEE_PC's function is there.
1040 Any CALL_SITE in CHAIN will be iterated to its siblings - via
1041 TAIL_CALL_NEXT. This is inappropriate for CALLER_PC's call_site. */
1042 std::vector
<struct call_site
*> chain
;
1044 /* We are not interested in the specific PC inside the callee function. */
1045 callee_pc
= get_pc_function_start (callee_pc
);
1047 throw_error (NO_ENTRY_VALUE_ERROR
, _("Unable to find function for PC %s"),
1048 paddress (gdbarch
, save_callee_pc
));
1050 /* Mark CALL_SITEs so we do not visit the same ones twice. */
1051 std::unordered_set
<CORE_ADDR
> addr_hash
;
1053 /* Do not push CALL_SITE to CHAIN. Push there only the first tail call site
1054 at the target's function. All the possible tail call sites in the
1055 target's function will get iterated as already pushed into CHAIN via their
1057 call_site
= call_site_for_pc (gdbarch
, caller_pc
);
1061 CORE_ADDR target_func_addr
;
1062 struct call_site
*target_call_site
;
1064 /* CALLER_FRAME with registers is not available for tail-call jumped
1066 target_func_addr
= call_site_to_target_addr (gdbarch
, call_site
, NULL
);
1068 if (target_func_addr
== callee_pc
)
1070 chain_candidate (gdbarch
, &retval
, &chain
);
1074 /* There is no way to reach CALLEE_PC again as we would prevent
1075 entering it twice as being already marked in ADDR_HASH. */
1076 target_call_site
= NULL
;
1080 struct symbol
*target_func
;
1082 target_func
= func_addr_to_tail_call_list (gdbarch
, target_func_addr
);
1083 target_call_site
= TYPE_TAIL_CALL_LIST (SYMBOL_TYPE (target_func
));
1088 /* Attempt to visit TARGET_CALL_SITE. */
1090 if (target_call_site
)
1092 if (addr_hash
.insert (target_call_site
->pc
).second
)
1094 /* Successfully entered TARGET_CALL_SITE. */
1096 chain
.push_back (target_call_site
);
1101 /* Backtrack (without revisiting the originating call_site). Try the
1102 callers's sibling; if there isn't any try the callers's callers's
1105 target_call_site
= NULL
;
1106 while (!chain
.empty ())
1108 call_site
= chain
.back ();
1111 size_t removed
= addr_hash
.erase (call_site
->pc
);
1112 gdb_assert (removed
== 1);
1114 target_call_site
= call_site
->tail_call_next
;
1115 if (target_call_site
)
1119 while (target_call_site
);
1124 call_site
= chain
.back ();
1129 struct bound_minimal_symbol msym_caller
, msym_callee
;
1131 msym_caller
= lookup_minimal_symbol_by_pc (caller_pc
);
1132 msym_callee
= lookup_minimal_symbol_by_pc (callee_pc
);
1133 throw_error (NO_ENTRY_VALUE_ERROR
,
1134 _("There are no unambiguously determinable intermediate "
1135 "callers or callees between caller function \"%s\" at %s "
1136 "and callee function \"%s\" at %s"),
1137 (msym_caller
.minsym
== NULL
1138 ? "???" : MSYMBOL_PRINT_NAME (msym_caller
.minsym
)),
1139 paddress (gdbarch
, caller_pc
),
1140 (msym_callee
.minsym
== NULL
1141 ? "???" : MSYMBOL_PRINT_NAME (msym_callee
.minsym
)),
1142 paddress (gdbarch
, callee_pc
));
1145 return retval
.release ();
1148 /* Create and return call_site_chain for CALLER_PC and CALLEE_PC. All the
1149 assumed frames between them use GDBARCH. If valid call_site_chain cannot be
1150 constructed return NULL. Caller is responsible for xfree of the returned
1153 struct call_site_chain
*
1154 call_site_find_chain (struct gdbarch
*gdbarch
, CORE_ADDR caller_pc
,
1155 CORE_ADDR callee_pc
)
1157 struct call_site_chain
*retval
= NULL
;
1161 retval
= call_site_find_chain_1 (gdbarch
, caller_pc
, callee_pc
);
1163 CATCH (e
, RETURN_MASK_ERROR
)
1165 if (e
.error
== NO_ENTRY_VALUE_ERROR
)
1167 if (entry_values_debug
)
1168 exception_print (gdb_stdout
, e
);
1173 throw_exception (e
);
1180 /* Return 1 if KIND and KIND_U match PARAMETER. Return 0 otherwise. */
1183 call_site_parameter_matches (struct call_site_parameter
*parameter
,
1184 enum call_site_parameter_kind kind
,
1185 union call_site_parameter_u kind_u
)
1187 if (kind
== parameter
->kind
)
1190 case CALL_SITE_PARAMETER_DWARF_REG
:
1191 return kind_u
.dwarf_reg
== parameter
->u
.dwarf_reg
;
1192 case CALL_SITE_PARAMETER_FB_OFFSET
:
1193 return kind_u
.fb_offset
== parameter
->u
.fb_offset
;
1194 case CALL_SITE_PARAMETER_PARAM_OFFSET
:
1195 return kind_u
.param_cu_off
== parameter
->u
.param_cu_off
;
1200 /* Fetch call_site_parameter from caller matching KIND and KIND_U.
1201 FRAME is for callee.
1203 Function always returns non-NULL, it throws NO_ENTRY_VALUE_ERROR
1206 static struct call_site_parameter
*
1207 dwarf_expr_reg_to_entry_parameter (struct frame_info
*frame
,
1208 enum call_site_parameter_kind kind
,
1209 union call_site_parameter_u kind_u
,
1210 struct dwarf2_per_cu_data
**per_cu_return
)
1212 CORE_ADDR func_addr
, caller_pc
;
1213 struct gdbarch
*gdbarch
;
1214 struct frame_info
*caller_frame
;
1215 struct call_site
*call_site
;
1217 /* Initialize it just to avoid a GCC false warning. */
1218 struct call_site_parameter
*parameter
= NULL
;
1219 CORE_ADDR target_addr
;
1221 while (get_frame_type (frame
) == INLINE_FRAME
)
1223 frame
= get_prev_frame (frame
);
1224 gdb_assert (frame
!= NULL
);
1227 func_addr
= get_frame_func (frame
);
1228 gdbarch
= get_frame_arch (frame
);
1229 caller_frame
= get_prev_frame (frame
);
1230 if (gdbarch
!= frame_unwind_arch (frame
))
1232 struct bound_minimal_symbol msym
1233 = lookup_minimal_symbol_by_pc (func_addr
);
1234 struct gdbarch
*caller_gdbarch
= frame_unwind_arch (frame
);
1236 throw_error (NO_ENTRY_VALUE_ERROR
,
1237 _("DW_OP_entry_value resolving callee gdbarch %s "
1238 "(of %s (%s)) does not match caller gdbarch %s"),
1239 gdbarch_bfd_arch_info (gdbarch
)->printable_name
,
1240 paddress (gdbarch
, func_addr
),
1241 (msym
.minsym
== NULL
? "???"
1242 : MSYMBOL_PRINT_NAME (msym
.minsym
)),
1243 gdbarch_bfd_arch_info (caller_gdbarch
)->printable_name
);
1246 if (caller_frame
== NULL
)
1248 struct bound_minimal_symbol msym
1249 = lookup_minimal_symbol_by_pc (func_addr
);
1251 throw_error (NO_ENTRY_VALUE_ERROR
, _("DW_OP_entry_value resolving "
1252 "requires caller of %s (%s)"),
1253 paddress (gdbarch
, func_addr
),
1254 (msym
.minsym
== NULL
? "???"
1255 : MSYMBOL_PRINT_NAME (msym
.minsym
)));
1257 caller_pc
= get_frame_pc (caller_frame
);
1258 call_site
= call_site_for_pc (gdbarch
, caller_pc
);
1260 target_addr
= call_site_to_target_addr (gdbarch
, call_site
, caller_frame
);
1261 if (target_addr
!= func_addr
)
1263 struct minimal_symbol
*target_msym
, *func_msym
;
1265 target_msym
= lookup_minimal_symbol_by_pc (target_addr
).minsym
;
1266 func_msym
= lookup_minimal_symbol_by_pc (func_addr
).minsym
;
1267 throw_error (NO_ENTRY_VALUE_ERROR
,
1268 _("DW_OP_entry_value resolving expects callee %s at %s "
1269 "but the called frame is for %s at %s"),
1270 (target_msym
== NULL
? "???"
1271 : MSYMBOL_PRINT_NAME (target_msym
)),
1272 paddress (gdbarch
, target_addr
),
1273 func_msym
== NULL
? "???" : MSYMBOL_PRINT_NAME (func_msym
),
1274 paddress (gdbarch
, func_addr
));
1277 /* No entry value based parameters would be reliable if this function can
1278 call itself via tail calls. */
1279 func_verify_no_selftailcall (gdbarch
, func_addr
);
1281 for (iparams
= 0; iparams
< call_site
->parameter_count
; iparams
++)
1283 parameter
= &call_site
->parameter
[iparams
];
1284 if (call_site_parameter_matches (parameter
, kind
, kind_u
))
1287 if (iparams
== call_site
->parameter_count
)
1289 struct minimal_symbol
*msym
1290 = lookup_minimal_symbol_by_pc (caller_pc
).minsym
;
1292 /* DW_TAG_call_site_parameter will be missing just if GCC could not
1293 determine its value. */
1294 throw_error (NO_ENTRY_VALUE_ERROR
, _("Cannot find matching parameter "
1295 "at DW_TAG_call_site %s at %s"),
1296 paddress (gdbarch
, caller_pc
),
1297 msym
== NULL
? "???" : MSYMBOL_PRINT_NAME (msym
));
1300 *per_cu_return
= call_site
->per_cu
;
1304 /* Return value for PARAMETER matching DEREF_SIZE. If DEREF_SIZE is -1, return
1305 the normal DW_AT_call_value block. Otherwise return the
1306 DW_AT_call_data_value (dereferenced) block.
1308 TYPE and CALLER_FRAME specify how to evaluate the DWARF block into returned
1311 Function always returns non-NULL, non-optimized out value. It throws
1312 NO_ENTRY_VALUE_ERROR if it cannot resolve the value for any reason. */
1314 static struct value
*
1315 dwarf_entry_parameter_to_value (struct call_site_parameter
*parameter
,
1316 CORE_ADDR deref_size
, struct type
*type
,
1317 struct frame_info
*caller_frame
,
1318 struct dwarf2_per_cu_data
*per_cu
)
1320 const gdb_byte
*data_src
;
1324 data_src
= deref_size
== -1 ? parameter
->value
: parameter
->data_value
;
1325 size
= deref_size
== -1 ? parameter
->value_size
: parameter
->data_value_size
;
1327 /* DEREF_SIZE size is not verified here. */
1328 if (data_src
== NULL
)
1329 throw_error (NO_ENTRY_VALUE_ERROR
,
1330 _("Cannot resolve DW_AT_call_data_value"));
1332 /* DW_AT_call_value is a DWARF expression, not a DWARF
1333 location. Postprocessing of DWARF_VALUE_MEMORY would lose the type from
1335 data
= (gdb_byte
*) alloca (size
+ 1);
1336 memcpy (data
, data_src
, size
);
1337 data
[size
] = DW_OP_stack_value
;
1339 return dwarf2_evaluate_loc_desc (type
, caller_frame
, data
, size
+ 1, per_cu
);
1342 /* VALUE must be of type lval_computed with entry_data_value_funcs. Perform
1343 the indirect method on it, that is use its stored target value, the sole
1344 purpose of entry_data_value_funcs.. */
1346 static struct value
*
1347 entry_data_value_coerce_ref (const struct value
*value
)
1349 struct type
*checked_type
= check_typedef (value_type (value
));
1350 struct value
*target_val
;
1352 if (!TYPE_IS_REFERENCE (checked_type
))
1355 target_val
= (struct value
*) value_computed_closure (value
);
1356 value_incref (target_val
);
1360 /* Implement copy_closure. */
1363 entry_data_value_copy_closure (const struct value
*v
)
1365 struct value
*target_val
= (struct value
*) value_computed_closure (v
);
1367 value_incref (target_val
);
1371 /* Implement free_closure. */
1374 entry_data_value_free_closure (struct value
*v
)
1376 struct value
*target_val
= (struct value
*) value_computed_closure (v
);
1378 value_free (target_val
);
1381 /* Vector for methods for an entry value reference where the referenced value
1382 is stored in the caller. On the first dereference use
1383 DW_AT_call_data_value in the caller. */
1385 static const struct lval_funcs entry_data_value_funcs
=
1389 NULL
, /* indirect */
1390 entry_data_value_coerce_ref
,
1391 NULL
, /* check_synthetic_pointer */
1392 entry_data_value_copy_closure
,
1393 entry_data_value_free_closure
1396 /* Read parameter of TYPE at (callee) FRAME's function entry. KIND and KIND_U
1397 are used to match DW_AT_location at the caller's
1398 DW_TAG_call_site_parameter.
1400 Function always returns non-NULL value. It throws NO_ENTRY_VALUE_ERROR if it
1401 cannot resolve the parameter for any reason. */
1403 static struct value
*
1404 value_of_dwarf_reg_entry (struct type
*type
, struct frame_info
*frame
,
1405 enum call_site_parameter_kind kind
,
1406 union call_site_parameter_u kind_u
)
1408 struct type
*checked_type
= check_typedef (type
);
1409 struct type
*target_type
= TYPE_TARGET_TYPE (checked_type
);
1410 struct frame_info
*caller_frame
= get_prev_frame (frame
);
1411 struct value
*outer_val
, *target_val
, *val
;
1412 struct call_site_parameter
*parameter
;
1413 struct dwarf2_per_cu_data
*caller_per_cu
;
1415 parameter
= dwarf_expr_reg_to_entry_parameter (frame
, kind
, kind_u
,
1418 outer_val
= dwarf_entry_parameter_to_value (parameter
, -1 /* deref_size */,
1422 /* Check if DW_AT_call_data_value cannot be used. If it should be
1423 used and it is not available do not fall back to OUTER_VAL - dereferencing
1424 TYPE_CODE_REF with non-entry data value would give current value - not the
1427 if (!TYPE_IS_REFERENCE (checked_type
)
1428 || TYPE_TARGET_TYPE (checked_type
) == NULL
)
1431 target_val
= dwarf_entry_parameter_to_value (parameter
,
1432 TYPE_LENGTH (target_type
),
1433 target_type
, caller_frame
,
1436 release_value (target_val
);
1437 val
= allocate_computed_value (type
, &entry_data_value_funcs
,
1438 target_val
/* closure */);
1440 /* Copy the referencing pointer to the new computed value. */
1441 memcpy (value_contents_raw (val
), value_contents_raw (outer_val
),
1442 TYPE_LENGTH (checked_type
));
1443 set_value_lazy (val
, 0);
1448 /* Read parameter of TYPE at (callee) FRAME's function entry. DATA and
1449 SIZE are DWARF block used to match DW_AT_location at the caller's
1450 DW_TAG_call_site_parameter.
1452 Function always returns non-NULL value. It throws NO_ENTRY_VALUE_ERROR if it
1453 cannot resolve the parameter for any reason. */
1455 static struct value
*
1456 value_of_dwarf_block_entry (struct type
*type
, struct frame_info
*frame
,
1457 const gdb_byte
*block
, size_t block_len
)
1459 union call_site_parameter_u kind_u
;
1461 kind_u
.dwarf_reg
= dwarf_block_to_dwarf_reg (block
, block
+ block_len
);
1462 if (kind_u
.dwarf_reg
!= -1)
1463 return value_of_dwarf_reg_entry (type
, frame
, CALL_SITE_PARAMETER_DWARF_REG
,
1466 if (dwarf_block_to_fb_offset (block
, block
+ block_len
, &kind_u
.fb_offset
))
1467 return value_of_dwarf_reg_entry (type
, frame
, CALL_SITE_PARAMETER_FB_OFFSET
,
1470 /* This can normally happen - throw NO_ENTRY_VALUE_ERROR to get the message
1471 suppressed during normal operation. The expression can be arbitrary if
1472 there is no caller-callee entry value binding expected. */
1473 throw_error (NO_ENTRY_VALUE_ERROR
,
1474 _("DWARF-2 expression error: DW_OP_entry_value is supported "
1475 "only for single DW_OP_reg* or for DW_OP_fbreg(*)"));
1478 struct piece_closure
1480 /* Reference count. */
1483 /* The CU from which this closure's expression came. */
1484 struct dwarf2_per_cu_data
*per_cu
;
1486 /* The number of pieces used to describe this variable. */
1489 /* The pieces themselves. */
1490 struct dwarf_expr_piece
*pieces
;
1492 /* Frame ID of frame to which a register value is relative, used
1493 only by DWARF_VALUE_REGISTER. */
1494 struct frame_id frame_id
;
1497 /* Allocate a closure for a value formed from separately-described
1500 static struct piece_closure
*
1501 allocate_piece_closure (struct dwarf2_per_cu_data
*per_cu
,
1502 int n_pieces
, struct dwarf_expr_piece
*pieces
,
1503 struct frame_info
*frame
)
1505 struct piece_closure
*c
= XCNEW (struct piece_closure
);
1510 c
->n_pieces
= n_pieces
;
1511 c
->pieces
= XCNEWVEC (struct dwarf_expr_piece
, n_pieces
);
1513 c
->frame_id
= null_frame_id
;
1515 c
->frame_id
= get_frame_id (frame
);
1517 memcpy (c
->pieces
, pieces
, n_pieces
* sizeof (struct dwarf_expr_piece
));
1518 for (i
= 0; i
< n_pieces
; ++i
)
1519 if (c
->pieces
[i
].location
== DWARF_VALUE_STACK
)
1520 value_incref (c
->pieces
[i
].v
.value
);
1525 /* Copy NBITS bits from SOURCE to DEST starting at the given bit
1526 offsets. Use the bit order as specified by BITS_BIG_ENDIAN.
1527 Source and destination buffers must not overlap. */
1530 copy_bitwise (gdb_byte
*dest
, ULONGEST dest_offset
,
1531 const gdb_byte
*source
, ULONGEST source_offset
,
1532 ULONGEST nbits
, int bits_big_endian
)
1534 unsigned int buf
, avail
;
1539 if (bits_big_endian
)
1541 /* Start from the end, then work backwards. */
1542 dest_offset
+= nbits
- 1;
1543 dest
+= dest_offset
/ 8;
1544 dest_offset
= 7 - dest_offset
% 8;
1545 source_offset
+= nbits
- 1;
1546 source
+= source_offset
/ 8;
1547 source_offset
= 7 - source_offset
% 8;
1551 dest
+= dest_offset
/ 8;
1553 source
+= source_offset
/ 8;
1557 /* Fill BUF with DEST_OFFSET bits from the destination and 8 -
1558 SOURCE_OFFSET bits from the source. */
1559 buf
= *(bits_big_endian
? source
-- : source
++) >> source_offset
;
1560 buf
<<= dest_offset
;
1561 buf
|= *dest
& ((1 << dest_offset
) - 1);
1563 /* NBITS: bits yet to be written; AVAIL: BUF's fill level. */
1564 nbits
+= dest_offset
;
1565 avail
= dest_offset
+ 8 - source_offset
;
1567 /* Flush 8 bits from BUF, if appropriate. */
1568 if (nbits
>= 8 && avail
>= 8)
1570 *(bits_big_endian
? dest
-- : dest
++) = buf
;
1576 /* Copy the middle part. */
1579 size_t len
= nbits
/ 8;
1581 /* Use a faster method for byte-aligned copies. */
1584 if (bits_big_endian
)
1588 memcpy (dest
+ 1, source
+ 1, len
);
1592 memcpy (dest
, source
, len
);
1601 buf
|= *(bits_big_endian
? source
-- : source
++) << avail
;
1602 *(bits_big_endian
? dest
-- : dest
++) = buf
;
1609 /* Write the last byte. */
1613 buf
|= *source
<< avail
;
1615 buf
&= (1 << nbits
) - 1;
1616 *dest
= (*dest
& (~0 << nbits
)) | buf
;
1622 namespace selftests
{
1624 /* Helper function for the unit test of copy_bitwise. Convert NBITS bits
1625 out of BITS, starting at OFFS, to the respective '0'/'1'-string. MSB0
1626 specifies whether to assume big endian bit numbering. Store the
1627 resulting (not null-terminated) string at STR. */
1630 bits_to_str (char *str
, const gdb_byte
*bits
, ULONGEST offs
,
1631 ULONGEST nbits
, int msb0
)
1636 for (i
= offs
/ 8, j
= offs
% 8; nbits
; i
++, j
= 0)
1638 unsigned int ch
= bits
[i
];
1639 for (; j
< 8 && nbits
; j
++, nbits
--)
1640 *str
++ = (ch
& (msb0
? (1 << (7 - j
)) : (1 << j
))) ? '1' : '0';
1644 /* Check one invocation of copy_bitwise with the given parameters. */
1647 check_copy_bitwise (const gdb_byte
*dest
, unsigned int dest_offset
,
1648 const gdb_byte
*source
, unsigned int source_offset
,
1649 unsigned int nbits
, int msb0
)
1651 size_t len
= align_up (dest_offset
+ nbits
, 8);
1652 char *expected
= (char *) alloca (len
+ 1);
1653 char *actual
= (char *) alloca (len
+ 1);
1654 gdb_byte
*buf
= (gdb_byte
*) alloca (len
/ 8);
1656 /* Compose a '0'/'1'-string that represents the expected result of
1658 Bits from [0, DEST_OFFSET) are filled from DEST.
1659 Bits from [DEST_OFFSET, DEST_OFFSET + NBITS) are filled from SOURCE.
1660 Bits from [DEST_OFFSET + NBITS, LEN) are filled from DEST.
1669 We should end up with:
1671 DDDDSSDD (D=dest, S=source)
1673 bits_to_str (expected
, dest
, 0, len
, msb0
);
1674 bits_to_str (expected
+ dest_offset
, source
, source_offset
, nbits
, msb0
);
1676 /* Fill BUF with data from DEST, apply copy_bitwise, and convert the
1677 result to a '0'/'1'-string. */
1678 memcpy (buf
, dest
, len
/ 8);
1679 copy_bitwise (buf
, dest_offset
, source
, source_offset
, nbits
, msb0
);
1680 bits_to_str (actual
, buf
, 0, len
, msb0
);
1682 /* Compare the resulting strings. */
1683 expected
[len
] = actual
[len
] = '\0';
1684 if (strcmp (expected
, actual
) != 0)
1685 error (_("copy_bitwise %s != %s (%u+%u -> %u)"),
1686 expected
, actual
, source_offset
, nbits
, dest_offset
);
1689 /* Unit test for copy_bitwise. */
1692 copy_bitwise_tests (void)
1694 /* Data to be used as both source and destination buffers. The two
1695 arrays below represent the lsb0- and msb0- encoded versions of the
1696 following bit string, respectively:
1697 00000000 00011111 11111111 01001000 10100101 11110010
1698 This pattern is chosen such that it contains:
1699 - constant 0- and 1- chunks of more than a full byte;
1700 - 0/1- and 1/0 transitions on all bit positions within a byte;
1701 - several sufficiently asymmetric bytes.
1703 static const gdb_byte data_lsb0
[] = {
1704 0x00, 0xf8, 0xff, 0x12, 0xa5, 0x4f
1706 static const gdb_byte data_msb0
[] = {
1707 0x00, 0x1f, 0xff, 0x48, 0xa5, 0xf2
1710 constexpr size_t data_nbits
= 8 * sizeof (data_lsb0
);
1711 constexpr unsigned max_nbits
= 24;
1713 /* Try all combinations of:
1714 lsb0/msb0 bit order (using the respective data array)
1715 X [0, MAX_NBITS] copy bit width
1716 X feasible source offsets for the given copy bit width
1717 X feasible destination offsets
1719 for (int msb0
= 0; msb0
< 2; msb0
++)
1721 const gdb_byte
*data
= msb0
? data_msb0
: data_lsb0
;
1723 for (unsigned int nbits
= 1; nbits
<= max_nbits
; nbits
++)
1725 const unsigned int max_offset
= data_nbits
- nbits
;
1727 for (unsigned source_offset
= 0;
1728 source_offset
<= max_offset
;
1731 for (unsigned dest_offset
= 0;
1732 dest_offset
<= max_offset
;
1735 check_copy_bitwise (data
+ dest_offset
/ 8,
1737 data
+ source_offset
/ 8,
1744 /* Special cases: copy all, copy nothing. */
1745 check_copy_bitwise (data_lsb0
, 0, data_msb0
, 0, data_nbits
, msb0
);
1746 check_copy_bitwise (data_msb0
, 0, data_lsb0
, 0, data_nbits
, msb0
);
1747 check_copy_bitwise (data
, data_nbits
- 7, data
, 9, 0, msb0
);
1751 } /* namespace selftests */
1753 #endif /* GDB_SELF_TEST */
1756 read_pieced_value (struct value
*v
)
1759 LONGEST offset
= 0, max_offset
;
1760 ULONGEST bits_to_skip
;
1762 struct piece_closure
*c
1763 = (struct piece_closure
*) value_computed_closure (v
);
1764 std::vector
<gdb_byte
> buffer
;
1766 = gdbarch_bits_big_endian (get_type_arch (value_type (v
)));
1768 if (value_type (v
) != value_enclosing_type (v
))
1769 internal_error (__FILE__
, __LINE__
,
1770 _("Should not be able to create a lazy value with "
1771 "an enclosing type"));
1773 contents
= value_contents_raw (v
);
1774 bits_to_skip
= 8 * value_offset (v
);
1775 if (value_bitsize (v
))
1777 bits_to_skip
+= (8 * value_offset (value_parent (v
))
1778 + value_bitpos (v
));
1779 max_offset
= value_bitsize (v
);
1782 max_offset
= 8 * TYPE_LENGTH (value_type (v
));
1784 for (i
= 0; i
< c
->n_pieces
&& offset
< max_offset
; i
++)
1786 struct dwarf_expr_piece
*p
= &c
->pieces
[i
];
1787 size_t this_size
, this_size_bits
;
1788 long dest_offset_bits
, source_offset_bits
, source_offset
;
1789 const gdb_byte
*intermediate_buffer
;
1791 /* Compute size, source, and destination offsets for copying, in
1793 this_size_bits
= p
->size
;
1794 if (bits_to_skip
> 0 && bits_to_skip
>= this_size_bits
)
1796 bits_to_skip
-= this_size_bits
;
1799 source_offset_bits
= bits_to_skip
;
1800 this_size_bits
-= bits_to_skip
;
1802 dest_offset_bits
= offset
;
1804 if (this_size_bits
> max_offset
- offset
)
1805 this_size_bits
= max_offset
- offset
;
1807 this_size
= (this_size_bits
+ source_offset_bits
% 8 + 7) / 8;
1808 buffer
.reserve (this_size
);
1809 source_offset
= source_offset_bits
/ 8;
1810 intermediate_buffer
= buffer
.data ();
1812 /* Copy from the source to DEST_BUFFER. */
1813 switch (p
->location
)
1815 case DWARF_VALUE_REGISTER
:
1817 struct frame_info
*frame
= frame_find_by_id (c
->frame_id
);
1818 struct gdbarch
*arch
= get_frame_arch (frame
);
1819 int gdb_regnum
= dwarf_reg_to_regnum_or_error (arch
, p
->v
.regno
);
1821 LONGEST reg_offset
= source_offset
;
1823 if (gdbarch_byte_order (arch
) == BFD_ENDIAN_BIG
1824 && this_size
< register_size (arch
, gdb_regnum
))
1826 /* Big-endian, and we want less than full size. */
1827 reg_offset
= register_size (arch
, gdb_regnum
) - this_size
;
1828 /* We want the lower-order THIS_SIZE_BITS of the bytes
1829 we extract from the register. */
1830 source_offset_bits
+= 8 * this_size
- this_size_bits
;
1833 if (!get_frame_register_bytes (frame
, gdb_regnum
, reg_offset
,
1834 this_size
, buffer
.data (),
1837 /* Just so garbage doesn't ever shine through. */
1838 memset (buffer
.data (), 0, this_size
);
1841 mark_value_bits_optimized_out (v
, offset
, this_size_bits
);
1843 mark_value_bits_unavailable (v
, offset
, this_size_bits
);
1846 copy_bitwise (contents
, dest_offset_bits
,
1847 intermediate_buffer
, source_offset_bits
% 8,
1848 this_size_bits
, bits_big_endian
);
1852 case DWARF_VALUE_MEMORY
:
1853 read_value_memory (v
, offset
,
1854 p
->v
.mem
.in_stack_memory
,
1855 p
->v
.mem
.addr
+ source_offset
,
1856 buffer
.data (), this_size
);
1857 copy_bitwise (contents
, dest_offset_bits
,
1858 intermediate_buffer
, source_offset_bits
% 8,
1859 this_size_bits
, bits_big_endian
);
1862 case DWARF_VALUE_STACK
:
1864 struct objfile
*objfile
= dwarf2_per_cu_objfile (c
->per_cu
);
1865 struct gdbarch
*objfile_gdbarch
= get_objfile_arch (objfile
);
1866 ULONGEST stack_value_size_bits
1867 = 8 * TYPE_LENGTH (value_type (p
->v
.value
));
1869 /* Use zeroes if piece reaches beyond stack value. */
1870 if (p
->size
> stack_value_size_bits
)
1873 /* Piece is anchored at least significant bit end. */
1874 if (gdbarch_byte_order (objfile_gdbarch
) == BFD_ENDIAN_BIG
)
1875 source_offset_bits
+= stack_value_size_bits
- p
->size
;
1877 copy_bitwise (contents
, dest_offset_bits
,
1878 value_contents_all (p
->v
.value
),
1880 this_size_bits
, bits_big_endian
);
1884 case DWARF_VALUE_LITERAL
:
1886 size_t n
= this_size
;
1888 if (n
> p
->v
.literal
.length
- source_offset
)
1889 n
= (p
->v
.literal
.length
>= source_offset
1890 ? p
->v
.literal
.length
- source_offset
1893 intermediate_buffer
= p
->v
.literal
.data
+ source_offset
;
1895 copy_bitwise (contents
, dest_offset_bits
,
1896 intermediate_buffer
, source_offset_bits
% 8,
1897 this_size_bits
, bits_big_endian
);
1901 /* These bits show up as zeros -- but do not cause the value
1902 to be considered optimized-out. */
1903 case DWARF_VALUE_IMPLICIT_POINTER
:
1906 case DWARF_VALUE_OPTIMIZED_OUT
:
1907 mark_value_bits_optimized_out (v
, offset
, this_size_bits
);
1911 internal_error (__FILE__
, __LINE__
, _("invalid location type"));
1914 offset
+= this_size_bits
;
1919 write_pieced_value (struct value
*to
, struct value
*from
)
1922 ULONGEST bits_to_skip
;
1923 LONGEST offset
= 0, max_offset
;
1924 const gdb_byte
*contents
;
1925 struct piece_closure
*c
1926 = (struct piece_closure
*) value_computed_closure (to
);
1927 std::vector
<gdb_byte
> buffer
;
1929 = gdbarch_bits_big_endian (get_type_arch (value_type (to
)));
1931 contents
= value_contents (from
);
1932 bits_to_skip
= 8 * value_offset (to
);
1933 if (value_bitsize (to
))
1935 bits_to_skip
+= (8 * value_offset (value_parent (to
))
1936 + value_bitpos (to
));
1937 /* Use the least significant bits of FROM. */
1938 if (gdbarch_byte_order (get_type_arch (value_type (from
)))
1941 max_offset
= 8 * TYPE_LENGTH (value_type (from
));
1942 offset
= max_offset
- value_bitsize (to
);
1945 max_offset
= value_bitsize (to
);
1948 max_offset
= 8 * TYPE_LENGTH (value_type (to
));
1950 for (i
= 0; i
< c
->n_pieces
&& offset
< max_offset
; i
++)
1952 struct dwarf_expr_piece
*p
= &c
->pieces
[i
];
1953 size_t this_size_bits
, this_size
;
1954 long dest_offset_bits
, source_offset_bits
, dest_offset
, source_offset
;
1956 const gdb_byte
*source_buffer
;
1958 this_size_bits
= p
->size
;
1959 if (bits_to_skip
> 0 && bits_to_skip
>= this_size_bits
)
1961 bits_to_skip
-= this_size_bits
;
1964 dest_offset_bits
= bits_to_skip
;
1965 this_size_bits
-= bits_to_skip
;
1967 source_offset_bits
= offset
;
1969 if (this_size_bits
> max_offset
- offset
)
1970 this_size_bits
= max_offset
- offset
;
1972 this_size
= (this_size_bits
+ dest_offset_bits
% 8 + 7) / 8;
1973 source_offset
= source_offset_bits
/ 8;
1974 dest_offset
= dest_offset_bits
/ 8;
1976 /* Check whether the data can be transferred byte-wise. */
1977 if (dest_offset_bits
% 8 == 0 && source_offset_bits
% 8 == 0
1978 && this_size_bits
% 8 == 0)
1980 source_buffer
= contents
+ source_offset
;
1985 buffer
.reserve (this_size
);
1986 source_buffer
= buffer
.data ();
1990 switch (p
->location
)
1992 case DWARF_VALUE_REGISTER
:
1994 struct frame_info
*frame
= frame_find_by_id (c
->frame_id
);
1995 struct gdbarch
*arch
= get_frame_arch (frame
);
1996 int gdb_regnum
= dwarf_reg_to_regnum_or_error (arch
, p
->v
.regno
);
1997 int reg_offset
= dest_offset
;
1999 if (gdbarch_byte_order (arch
) == BFD_ENDIAN_BIG
2000 && this_size
<= register_size (arch
, gdb_regnum
))
2002 /* Big-endian, and we want less than full size. */
2003 reg_offset
= register_size (arch
, gdb_regnum
) - this_size
;
2010 if (!get_frame_register_bytes (frame
, gdb_regnum
, reg_offset
,
2011 this_size
, buffer
.data (),
2015 throw_error (OPTIMIZED_OUT_ERROR
,
2016 _("Can't do read-modify-write to "
2017 "update bitfield; containing word "
2018 "has been optimized out"));
2020 throw_error (NOT_AVAILABLE_ERROR
,
2021 _("Can't do read-modify-write to update "
2022 "bitfield; containing word "
2025 copy_bitwise (buffer
.data (), dest_offset_bits
,
2026 contents
, source_offset_bits
,
2031 put_frame_register_bytes (frame
, gdb_regnum
, reg_offset
,
2032 this_size
, source_buffer
);
2035 case DWARF_VALUE_MEMORY
:
2038 /* Only the first and last bytes can possibly have any
2040 read_memory (p
->v
.mem
.addr
+ dest_offset
, buffer
.data (), 1);
2041 read_memory (p
->v
.mem
.addr
+ dest_offset
+ this_size
- 1,
2042 &buffer
[this_size
- 1], 1);
2043 copy_bitwise (buffer
.data (), dest_offset_bits
% 8,
2044 contents
, source_offset_bits
,
2049 write_memory (p
->v
.mem
.addr
+ dest_offset
,
2050 source_buffer
, this_size
);
2053 mark_value_bytes_optimized_out (to
, 0, TYPE_LENGTH (value_type (to
)));
2056 offset
+= this_size_bits
;
2060 /* An implementation of an lval_funcs method to see whether a value is
2061 a synthetic pointer. */
2064 check_pieced_synthetic_pointer (const struct value
*value
, LONGEST bit_offset
,
2067 struct piece_closure
*c
2068 = (struct piece_closure
*) value_computed_closure (value
);
2071 bit_offset
+= 8 * value_offset (value
);
2072 if (value_bitsize (value
))
2073 bit_offset
+= value_bitpos (value
);
2075 for (i
= 0; i
< c
->n_pieces
&& bit_length
> 0; i
++)
2077 struct dwarf_expr_piece
*p
= &c
->pieces
[i
];
2078 size_t this_size_bits
= p
->size
;
2082 if (bit_offset
>= this_size_bits
)
2084 bit_offset
-= this_size_bits
;
2088 bit_length
-= this_size_bits
- bit_offset
;
2092 bit_length
-= this_size_bits
;
2094 if (p
->location
!= DWARF_VALUE_IMPLICIT_POINTER
)
2101 /* A wrapper function for get_frame_address_in_block. */
2104 get_frame_address_in_block_wrapper (void *baton
)
2106 return get_frame_address_in_block ((struct frame_info
*) baton
);
2109 /* Fetch a DW_AT_const_value through a synthetic pointer. */
2111 static struct value
*
2112 fetch_const_value_from_synthetic_pointer (sect_offset die
, LONGEST byte_offset
,
2113 struct dwarf2_per_cu_data
*per_cu
,
2116 struct value
*result
= NULL
;
2117 struct obstack temp_obstack
;
2118 struct cleanup
*cleanup
;
2119 const gdb_byte
*bytes
;
2122 obstack_init (&temp_obstack
);
2123 cleanup
= make_cleanup_obstack_free (&temp_obstack
);
2124 bytes
= dwarf2_fetch_constant_bytes (die
, per_cu
, &temp_obstack
, &len
);
2128 if (byte_offset
>= 0
2129 && byte_offset
+ TYPE_LENGTH (TYPE_TARGET_TYPE (type
)) <= len
)
2131 bytes
+= byte_offset
;
2132 result
= value_from_contents (TYPE_TARGET_TYPE (type
), bytes
);
2135 invalid_synthetic_pointer ();
2138 result
= allocate_optimized_out_value (TYPE_TARGET_TYPE (type
));
2140 do_cleanups (cleanup
);
2145 /* Fetch the value pointed to by a synthetic pointer. */
2147 static struct value
*
2148 indirect_synthetic_pointer (sect_offset die
, LONGEST byte_offset
,
2149 struct dwarf2_per_cu_data
*per_cu
,
2150 struct frame_info
*frame
, struct type
*type
)
2152 /* Fetch the location expression of the DIE we're pointing to. */
2153 struct dwarf2_locexpr_baton baton
2154 = dwarf2_fetch_die_loc_sect_off (die
, per_cu
,
2155 get_frame_address_in_block_wrapper
, frame
);
2157 /* Get type of pointed-to DIE. */
2158 struct type
*orig_type
= dwarf2_fetch_die_type_sect_off (die
, per_cu
);
2159 if (orig_type
== NULL
)
2160 invalid_synthetic_pointer ();
2162 /* If pointed-to DIE has a DW_AT_location, evaluate it and return the
2163 resulting value. Otherwise, it may have a DW_AT_const_value instead,
2164 or it may've been optimized out. */
2165 if (baton
.data
!= NULL
)
2166 return dwarf2_evaluate_loc_desc_full (orig_type
, frame
, baton
.data
,
2167 baton
.size
, baton
.per_cu
,
2168 TYPE_TARGET_TYPE (type
),
2171 return fetch_const_value_from_synthetic_pointer (die
, byte_offset
, per_cu
,
2175 /* An implementation of an lval_funcs method to indirect through a
2176 pointer. This handles the synthetic pointer case when needed. */
2178 static struct value
*
2179 indirect_pieced_value (struct value
*value
)
2181 struct piece_closure
*c
2182 = (struct piece_closure
*) value_computed_closure (value
);
2184 struct frame_info
*frame
;
2185 struct dwarf2_locexpr_baton baton
;
2188 struct dwarf_expr_piece
*piece
= NULL
;
2189 LONGEST byte_offset
;
2190 enum bfd_endian byte_order
;
2192 type
= check_typedef (value_type (value
));
2193 if (TYPE_CODE (type
) != TYPE_CODE_PTR
)
2196 bit_length
= 8 * TYPE_LENGTH (type
);
2197 bit_offset
= 8 * value_offset (value
);
2198 if (value_bitsize (value
))
2199 bit_offset
+= value_bitpos (value
);
2201 for (i
= 0; i
< c
->n_pieces
&& bit_length
> 0; i
++)
2203 struct dwarf_expr_piece
*p
= &c
->pieces
[i
];
2204 size_t this_size_bits
= p
->size
;
2208 if (bit_offset
>= this_size_bits
)
2210 bit_offset
-= this_size_bits
;
2214 bit_length
-= this_size_bits
- bit_offset
;
2218 bit_length
-= this_size_bits
;
2220 if (p
->location
!= DWARF_VALUE_IMPLICIT_POINTER
)
2223 if (bit_length
!= 0)
2224 error (_("Invalid use of DW_OP_implicit_pointer"));
2230 gdb_assert (piece
!= NULL
);
2231 frame
= get_selected_frame (_("No frame selected."));
2233 /* This is an offset requested by GDB, such as value subscripts.
2234 However, due to how synthetic pointers are implemented, this is
2235 always presented to us as a pointer type. This means we have to
2236 sign-extend it manually as appropriate. Use raw
2237 extract_signed_integer directly rather than value_as_address and
2238 sign extend afterwards on architectures that would need it
2239 (mostly everywhere except MIPS, which has signed addresses) as
2240 the later would go through gdbarch_pointer_to_address and thus
2241 return a CORE_ADDR with high bits set on architectures that
2242 encode address spaces and other things in CORE_ADDR. */
2243 byte_order
= gdbarch_byte_order (get_frame_arch (frame
));
2244 byte_offset
= extract_signed_integer (value_contents (value
),
2245 TYPE_LENGTH (type
), byte_order
);
2246 byte_offset
+= piece
->v
.ptr
.offset
;
2248 return indirect_synthetic_pointer (piece
->v
.ptr
.die_sect_off
,
2249 byte_offset
, c
->per_cu
,
2253 /* Implementation of the coerce_ref method of lval_funcs for synthetic C++
2256 static struct value
*
2257 coerce_pieced_ref (const struct value
*value
)
2259 struct type
*type
= check_typedef (value_type (value
));
2261 if (value_bits_synthetic_pointer (value
, value_embedded_offset (value
),
2262 TARGET_CHAR_BIT
* TYPE_LENGTH (type
)))
2264 const struct piece_closure
*closure
2265 = (struct piece_closure
*) value_computed_closure (value
);
2266 struct frame_info
*frame
2267 = get_selected_frame (_("No frame selected."));
2269 /* gdb represents synthetic pointers as pieced values with a single
2271 gdb_assert (closure
!= NULL
);
2272 gdb_assert (closure
->n_pieces
== 1);
2274 return indirect_synthetic_pointer (closure
->pieces
->v
.ptr
.die_sect_off
,
2275 closure
->pieces
->v
.ptr
.offset
,
2276 closure
->per_cu
, frame
, type
);
2280 /* Else: not a synthetic reference; do nothing. */
2286 copy_pieced_value_closure (const struct value
*v
)
2288 struct piece_closure
*c
2289 = (struct piece_closure
*) value_computed_closure (v
);
2296 free_pieced_value_closure (struct value
*v
)
2298 struct piece_closure
*c
2299 = (struct piece_closure
*) value_computed_closure (v
);
2306 for (i
= 0; i
< c
->n_pieces
; ++i
)
2307 if (c
->pieces
[i
].location
== DWARF_VALUE_STACK
)
2308 value_free (c
->pieces
[i
].v
.value
);
2315 /* Functions for accessing a variable described by DW_OP_piece. */
2316 static const struct lval_funcs pieced_value_funcs
= {
2319 indirect_pieced_value
,
2321 check_pieced_synthetic_pointer
,
2322 copy_pieced_value_closure
,
2323 free_pieced_value_closure
2326 /* Evaluate a location description, starting at DATA and with length
2327 SIZE, to find the current location of variable of TYPE in the
2328 context of FRAME. If SUBOBJ_TYPE is non-NULL, return instead the
2329 location of the subobject of type SUBOBJ_TYPE at byte offset
2330 SUBOBJ_BYTE_OFFSET within the variable of type TYPE. */
2332 static struct value
*
2333 dwarf2_evaluate_loc_desc_full (struct type
*type
, struct frame_info
*frame
,
2334 const gdb_byte
*data
, size_t size
,
2335 struct dwarf2_per_cu_data
*per_cu
,
2336 struct type
*subobj_type
,
2337 LONGEST subobj_byte_offset
)
2339 struct value
*retval
;
2340 struct objfile
*objfile
= dwarf2_per_cu_objfile (per_cu
);
2342 if (subobj_type
== NULL
)
2345 subobj_byte_offset
= 0;
2347 else if (subobj_byte_offset
< 0)
2348 invalid_synthetic_pointer ();
2351 return allocate_optimized_out_value (subobj_type
);
2353 dwarf_evaluate_loc_desc ctx
;
2355 ctx
.per_cu
= per_cu
;
2356 ctx
.obj_address
= 0;
2358 scoped_value_mark free_values
;
2360 ctx
.gdbarch
= get_objfile_arch (objfile
);
2361 ctx
.addr_size
= dwarf2_per_cu_addr_size (per_cu
);
2362 ctx
.ref_addr_size
= dwarf2_per_cu_ref_addr_size (per_cu
);
2363 ctx
.offset
= dwarf2_per_cu_text_offset (per_cu
);
2367 ctx
.eval (data
, size
);
2369 CATCH (ex
, RETURN_MASK_ERROR
)
2371 if (ex
.error
== NOT_AVAILABLE_ERROR
)
2373 free_values
.free_to_mark ();
2374 retval
= allocate_value (subobj_type
);
2375 mark_value_bytes_unavailable (retval
, 0,
2376 TYPE_LENGTH (subobj_type
));
2379 else if (ex
.error
== NO_ENTRY_VALUE_ERROR
)
2381 if (entry_values_debug
)
2382 exception_print (gdb_stdout
, ex
);
2383 free_values
.free_to_mark ();
2384 return allocate_optimized_out_value (subobj_type
);
2387 throw_exception (ex
);
2391 if (ctx
.num_pieces
> 0)
2393 struct piece_closure
*c
;
2394 ULONGEST bit_size
= 0;
2397 for (i
= 0; i
< ctx
.num_pieces
; ++i
)
2398 bit_size
+= ctx
.pieces
[i
].size
;
2399 if (8 * (subobj_byte_offset
+ TYPE_LENGTH (subobj_type
)) > bit_size
)
2400 invalid_synthetic_pointer ();
2402 c
= allocate_piece_closure (per_cu
, ctx
.num_pieces
, ctx
.pieces
,
2404 /* We must clean up the value chain after creating the piece
2405 closure but before allocating the result. */
2406 free_values
.free_to_mark ();
2407 retval
= allocate_computed_value (subobj_type
,
2408 &pieced_value_funcs
, c
);
2409 set_value_offset (retval
, subobj_byte_offset
);
2413 switch (ctx
.location
)
2415 case DWARF_VALUE_REGISTER
:
2417 struct gdbarch
*arch
= get_frame_arch (frame
);
2419 = longest_to_int (value_as_long (ctx
.fetch (0)));
2420 int gdb_regnum
= dwarf_reg_to_regnum_or_error (arch
, dwarf_regnum
);
2422 if (subobj_byte_offset
!= 0)
2423 error (_("cannot use offset on synthetic pointer to register"));
2424 free_values
.free_to_mark ();
2425 retval
= value_from_register (subobj_type
, gdb_regnum
, frame
);
2426 if (value_optimized_out (retval
))
2430 /* This means the register has undefined value / was
2431 not saved. As we're computing the location of some
2432 variable etc. in the program, not a value for
2433 inspecting a register ($pc, $sp, etc.), return a
2434 generic optimized out value instead, so that we show
2435 <optimized out> instead of <not saved>. */
2436 tmp
= allocate_value (subobj_type
);
2437 value_contents_copy (tmp
, 0, retval
, 0,
2438 TYPE_LENGTH (subobj_type
));
2444 case DWARF_VALUE_MEMORY
:
2446 struct type
*ptr_type
;
2447 CORE_ADDR address
= ctx
.fetch_address (0);
2448 int in_stack_memory
= ctx
.fetch_in_stack_memory (0);
2450 /* DW_OP_deref_size (and possibly other operations too) may
2451 create a pointer instead of an address. Ideally, the
2452 pointer to address conversion would be performed as part
2453 of those operations, but the type of the object to
2454 which the address refers is not known at the time of
2455 the operation. Therefore, we do the conversion here
2456 since the type is readily available. */
2458 switch (TYPE_CODE (subobj_type
))
2460 case TYPE_CODE_FUNC
:
2461 case TYPE_CODE_METHOD
:
2462 ptr_type
= builtin_type (ctx
.gdbarch
)->builtin_func_ptr
;
2465 ptr_type
= builtin_type (ctx
.gdbarch
)->builtin_data_ptr
;
2468 address
= value_as_address (value_from_pointer (ptr_type
, address
));
2470 free_values
.free_to_mark ();
2471 retval
= value_at_lazy (subobj_type
,
2472 address
+ subobj_byte_offset
);
2473 if (in_stack_memory
)
2474 set_value_stack (retval
, 1);
2478 case DWARF_VALUE_STACK
:
2480 struct value
*value
= ctx
.fetch (0);
2481 size_t n
= TYPE_LENGTH (value_type (value
));
2482 size_t len
= TYPE_LENGTH (subobj_type
);
2483 size_t max
= TYPE_LENGTH (type
);
2484 struct gdbarch
*objfile_gdbarch
= get_objfile_arch (objfile
);
2485 struct cleanup
*cleanup
;
2487 if (subobj_byte_offset
+ len
> max
)
2488 invalid_synthetic_pointer ();
2490 /* Preserve VALUE because we are going to free values back
2491 to the mark, but we still need the value contents
2493 value_incref (value
);
2494 free_values
.free_to_mark ();
2495 cleanup
= make_cleanup_value_free (value
);
2497 retval
= allocate_value (subobj_type
);
2499 /* The given offset is relative to the actual object. */
2500 if (gdbarch_byte_order (objfile_gdbarch
) == BFD_ENDIAN_BIG
)
2501 subobj_byte_offset
+= n
- max
;
2503 memcpy (value_contents_raw (retval
),
2504 value_contents_all (value
) + subobj_byte_offset
, len
);
2506 do_cleanups (cleanup
);
2510 case DWARF_VALUE_LITERAL
:
2513 size_t n
= TYPE_LENGTH (subobj_type
);
2515 if (subobj_byte_offset
+ n
> ctx
.len
)
2516 invalid_synthetic_pointer ();
2518 free_values
.free_to_mark ();
2519 retval
= allocate_value (subobj_type
);
2520 contents
= value_contents_raw (retval
);
2521 memcpy (contents
, ctx
.data
+ subobj_byte_offset
, n
);
2525 case DWARF_VALUE_OPTIMIZED_OUT
:
2526 free_values
.free_to_mark ();
2527 retval
= allocate_optimized_out_value (subobj_type
);
2530 /* DWARF_VALUE_IMPLICIT_POINTER was converted to a pieced
2531 operation by execute_stack_op. */
2532 case DWARF_VALUE_IMPLICIT_POINTER
:
2533 /* DWARF_VALUE_OPTIMIZED_OUT can't occur in this context --
2534 it can only be encountered when making a piece. */
2536 internal_error (__FILE__
, __LINE__
, _("invalid location type"));
2540 set_value_initialized (retval
, ctx
.initialized
);
2545 /* The exported interface to dwarf2_evaluate_loc_desc_full; it always
2546 passes 0 as the byte_offset. */
2549 dwarf2_evaluate_loc_desc (struct type
*type
, struct frame_info
*frame
,
2550 const gdb_byte
*data
, size_t size
,
2551 struct dwarf2_per_cu_data
*per_cu
)
2553 return dwarf2_evaluate_loc_desc_full (type
, frame
, data
, size
, per_cu
,
2557 /* Evaluates a dwarf expression and stores the result in VAL, expecting
2558 that the dwarf expression only produces a single CORE_ADDR. FRAME is the
2559 frame in which the expression is evaluated. ADDR is a context (location of
2560 a variable) and might be needed to evaluate the location expression.
2561 Returns 1 on success, 0 otherwise. */
2564 dwarf2_locexpr_baton_eval (const struct dwarf2_locexpr_baton
*dlbaton
,
2565 struct frame_info
*frame
,
2569 struct objfile
*objfile
;
2571 if (dlbaton
== NULL
|| dlbaton
->size
== 0)
2574 dwarf_evaluate_loc_desc ctx
;
2577 ctx
.per_cu
= dlbaton
->per_cu
;
2578 ctx
.obj_address
= addr
;
2580 objfile
= dwarf2_per_cu_objfile (dlbaton
->per_cu
);
2582 ctx
.gdbarch
= get_objfile_arch (objfile
);
2583 ctx
.addr_size
= dwarf2_per_cu_addr_size (dlbaton
->per_cu
);
2584 ctx
.ref_addr_size
= dwarf2_per_cu_ref_addr_size (dlbaton
->per_cu
);
2585 ctx
.offset
= dwarf2_per_cu_text_offset (dlbaton
->per_cu
);
2587 ctx
.eval (dlbaton
->data
, dlbaton
->size
);
2589 switch (ctx
.location
)
2591 case DWARF_VALUE_REGISTER
:
2592 case DWARF_VALUE_MEMORY
:
2593 case DWARF_VALUE_STACK
:
2594 *valp
= ctx
.fetch_address (0);
2595 if (ctx
.location
== DWARF_VALUE_REGISTER
)
2596 *valp
= ctx
.read_addr_from_reg (*valp
);
2598 case DWARF_VALUE_LITERAL
:
2599 *valp
= extract_signed_integer (ctx
.data
, ctx
.len
,
2600 gdbarch_byte_order (ctx
.gdbarch
));
2602 /* Unsupported dwarf values. */
2603 case DWARF_VALUE_OPTIMIZED_OUT
:
2604 case DWARF_VALUE_IMPLICIT_POINTER
:
2611 /* See dwarf2loc.h. */
2614 dwarf2_evaluate_property (const struct dynamic_prop
*prop
,
2615 struct frame_info
*frame
,
2616 struct property_addr_info
*addr_stack
,
2622 if (frame
== NULL
&& has_stack_frames ())
2623 frame
= get_selected_frame (NULL
);
2629 const struct dwarf2_property_baton
*baton
2630 = (const struct dwarf2_property_baton
*) prop
->data
.baton
;
2632 if (dwarf2_locexpr_baton_eval (&baton
->locexpr
, frame
,
2633 addr_stack
? addr_stack
->addr
: 0,
2636 if (baton
->referenced_type
)
2638 struct value
*val
= value_at (baton
->referenced_type
, *value
);
2640 *value
= value_as_address (val
);
2649 struct dwarf2_property_baton
*baton
2650 = (struct dwarf2_property_baton
*) prop
->data
.baton
;
2651 CORE_ADDR pc
= get_frame_address_in_block (frame
);
2652 const gdb_byte
*data
;
2656 data
= dwarf2_find_location_expression (&baton
->loclist
, &size
, pc
);
2659 val
= dwarf2_evaluate_loc_desc (baton
->referenced_type
, frame
, data
,
2660 size
, baton
->loclist
.per_cu
);
2661 if (!value_optimized_out (val
))
2663 *value
= value_as_address (val
);
2671 *value
= prop
->data
.const_val
;
2674 case PROP_ADDR_OFFSET
:
2676 struct dwarf2_property_baton
*baton
2677 = (struct dwarf2_property_baton
*) prop
->data
.baton
;
2678 struct property_addr_info
*pinfo
;
2681 for (pinfo
= addr_stack
; pinfo
!= NULL
; pinfo
= pinfo
->next
)
2682 if (pinfo
->type
== baton
->referenced_type
)
2685 error (_("cannot find reference address for offset property"));
2686 if (pinfo
->valaddr
!= NULL
)
2687 val
= value_from_contents
2688 (baton
->offset_info
.type
,
2689 pinfo
->valaddr
+ baton
->offset_info
.offset
);
2691 val
= value_at (baton
->offset_info
.type
,
2692 pinfo
->addr
+ baton
->offset_info
.offset
);
2693 *value
= value_as_address (val
);
2701 /* See dwarf2loc.h. */
2704 dwarf2_compile_property_to_c (string_file
&stream
,
2705 const char *result_name
,
2706 struct gdbarch
*gdbarch
,
2707 unsigned char *registers_used
,
2708 const struct dynamic_prop
*prop
,
2712 struct dwarf2_property_baton
*baton
2713 = (struct dwarf2_property_baton
*) prop
->data
.baton
;
2714 const gdb_byte
*data
;
2716 struct dwarf2_per_cu_data
*per_cu
;
2718 if (prop
->kind
== PROP_LOCEXPR
)
2720 data
= baton
->locexpr
.data
;
2721 size
= baton
->locexpr
.size
;
2722 per_cu
= baton
->locexpr
.per_cu
;
2726 gdb_assert (prop
->kind
== PROP_LOCLIST
);
2728 data
= dwarf2_find_location_expression (&baton
->loclist
, &size
, pc
);
2729 per_cu
= baton
->loclist
.per_cu
;
2732 compile_dwarf_bounds_to_c (stream
, result_name
, prop
, sym
, pc
,
2733 gdbarch
, registers_used
,
2734 dwarf2_per_cu_addr_size (per_cu
),
2735 data
, data
+ size
, per_cu
);
2739 /* Helper functions and baton for dwarf2_loc_desc_get_symbol_read_needs. */
2741 class symbol_needs_eval_context
: public dwarf_expr_context
2745 enum symbol_needs_kind needs
;
2746 struct dwarf2_per_cu_data
*per_cu
;
2748 /* Reads from registers do require a frame. */
2749 CORE_ADDR
read_addr_from_reg (int regnum
) OVERRIDE
2751 needs
= SYMBOL_NEEDS_FRAME
;
2755 /* "get_reg_value" callback: Reads from registers do require a
2758 struct value
*get_reg_value (struct type
*type
, int regnum
) OVERRIDE
2760 needs
= SYMBOL_NEEDS_FRAME
;
2761 return value_zero (type
, not_lval
);
2764 /* Reads from memory do not require a frame. */
2765 void read_mem (gdb_byte
*buf
, CORE_ADDR addr
, size_t len
) OVERRIDE
2767 memset (buf
, 0, len
);
2770 /* Frame-relative accesses do require a frame. */
2771 void get_frame_base (const gdb_byte
**start
, size_t *length
) OVERRIDE
2773 static gdb_byte lit0
= DW_OP_lit0
;
2778 needs
= SYMBOL_NEEDS_FRAME
;
2781 /* CFA accesses require a frame. */
2782 CORE_ADDR
get_frame_cfa () OVERRIDE
2784 needs
= SYMBOL_NEEDS_FRAME
;
2788 CORE_ADDR
get_frame_pc () OVERRIDE
2790 needs
= SYMBOL_NEEDS_FRAME
;
2794 /* Thread-local accesses require registers, but not a frame. */
2795 CORE_ADDR
get_tls_address (CORE_ADDR offset
) OVERRIDE
2797 if (needs
<= SYMBOL_NEEDS_REGISTERS
)
2798 needs
= SYMBOL_NEEDS_REGISTERS
;
2802 /* Helper interface of per_cu_dwarf_call for
2803 dwarf2_loc_desc_get_symbol_read_needs. */
2805 void dwarf_call (cu_offset die_offset
) OVERRIDE
2807 per_cu_dwarf_call (this, die_offset
, per_cu
);
2810 /* DW_OP_entry_value accesses require a caller, therefore a
2813 void push_dwarf_reg_entry_value (enum call_site_parameter_kind kind
,
2814 union call_site_parameter_u kind_u
,
2815 int deref_size
) OVERRIDE
2817 needs
= SYMBOL_NEEDS_FRAME
;
2819 /* The expression may require some stub values on DWARF stack. */
2820 push_address (0, 0);
2823 /* DW_OP_GNU_addr_index doesn't require a frame. */
2825 CORE_ADDR
get_addr_index (unsigned int index
) OVERRIDE
2827 /* Nothing to do. */
2831 /* DW_OP_push_object_address has a frame already passed through. */
2833 CORE_ADDR
get_object_address () OVERRIDE
2835 /* Nothing to do. */
2840 /* Compute the correct symbol_needs_kind value for the location
2841 expression at DATA (length SIZE). */
2843 static enum symbol_needs_kind
2844 dwarf2_loc_desc_get_symbol_read_needs (const gdb_byte
*data
, size_t size
,
2845 struct dwarf2_per_cu_data
*per_cu
)
2848 struct objfile
*objfile
= dwarf2_per_cu_objfile (per_cu
);
2850 scoped_value_mark free_values
;
2852 symbol_needs_eval_context ctx
;
2854 ctx
.needs
= SYMBOL_NEEDS_NONE
;
2855 ctx
.per_cu
= per_cu
;
2856 ctx
.gdbarch
= get_objfile_arch (objfile
);
2857 ctx
.addr_size
= dwarf2_per_cu_addr_size (per_cu
);
2858 ctx
.ref_addr_size
= dwarf2_per_cu_ref_addr_size (per_cu
);
2859 ctx
.offset
= dwarf2_per_cu_text_offset (per_cu
);
2861 ctx
.eval (data
, size
);
2863 in_reg
= ctx
.location
== DWARF_VALUE_REGISTER
;
2865 if (ctx
.num_pieces
> 0)
2869 /* If the location has several pieces, and any of them are in
2870 registers, then we will need a frame to fetch them from. */
2871 for (i
= 0; i
< ctx
.num_pieces
; i
++)
2872 if (ctx
.pieces
[i
].location
== DWARF_VALUE_REGISTER
)
2877 ctx
.needs
= SYMBOL_NEEDS_FRAME
;
2881 /* A helper function that throws an unimplemented error mentioning a
2882 given DWARF operator. */
2885 unimplemented (unsigned int op
)
2887 const char *name
= get_DW_OP_name (op
);
2890 error (_("DWARF operator %s cannot be translated to an agent expression"),
2893 error (_("Unknown DWARF operator 0x%02x cannot be translated "
2894 "to an agent expression"),
2900 This is basically a wrapper on gdbarch_dwarf2_reg_to_regnum so that we
2901 can issue a complaint, which is better than having every target's
2902 implementation of dwarf2_reg_to_regnum do it. */
2905 dwarf_reg_to_regnum (struct gdbarch
*arch
, int dwarf_reg
)
2907 int reg
= gdbarch_dwarf2_reg_to_regnum (arch
, dwarf_reg
);
2911 complaint (&symfile_complaints
,
2912 _("bad DWARF register number %d"), dwarf_reg
);
2917 /* Subroutine of dwarf_reg_to_regnum_or_error to simplify it.
2918 Throw an error because DWARF_REG is bad. */
2921 throw_bad_regnum_error (ULONGEST dwarf_reg
)
2923 /* Still want to print -1 as "-1".
2924 We *could* have int and ULONGEST versions of dwarf2_reg_to_regnum_or_error
2925 but that's overkill for now. */
2926 if ((int) dwarf_reg
== dwarf_reg
)
2927 error (_("Unable to access DWARF register number %d"), (int) dwarf_reg
);
2928 error (_("Unable to access DWARF register number %s"),
2929 pulongest (dwarf_reg
));
2932 /* See dwarf2loc.h. */
2935 dwarf_reg_to_regnum_or_error (struct gdbarch
*arch
, ULONGEST dwarf_reg
)
2939 if (dwarf_reg
> INT_MAX
)
2940 throw_bad_regnum_error (dwarf_reg
);
2941 /* Yes, we will end up issuing a complaint and an error if DWARF_REG is
2942 bad, but that's ok. */
2943 reg
= dwarf_reg_to_regnum (arch
, (int) dwarf_reg
);
2945 throw_bad_regnum_error (dwarf_reg
);
2949 /* A helper function that emits an access to memory. ARCH is the
2950 target architecture. EXPR is the expression which we are building.
2951 NBITS is the number of bits we want to read. This emits the
2952 opcodes needed to read the memory and then extract the desired
2956 access_memory (struct gdbarch
*arch
, struct agent_expr
*expr
, ULONGEST nbits
)
2958 ULONGEST nbytes
= (nbits
+ 7) / 8;
2960 gdb_assert (nbytes
> 0 && nbytes
<= sizeof (LONGEST
));
2963 ax_trace_quick (expr
, nbytes
);
2966 ax_simple (expr
, aop_ref8
);
2967 else if (nbits
<= 16)
2968 ax_simple (expr
, aop_ref16
);
2969 else if (nbits
<= 32)
2970 ax_simple (expr
, aop_ref32
);
2972 ax_simple (expr
, aop_ref64
);
2974 /* If we read exactly the number of bytes we wanted, we're done. */
2975 if (8 * nbytes
== nbits
)
2978 if (gdbarch_bits_big_endian (arch
))
2980 /* On a bits-big-endian machine, we want the high-order
2982 ax_const_l (expr
, 8 * nbytes
- nbits
);
2983 ax_simple (expr
, aop_rsh_unsigned
);
2987 /* On a bits-little-endian box, we want the low-order NBITS. */
2988 ax_zero_ext (expr
, nbits
);
2992 /* A helper function to return the frame's PC. */
2995 get_ax_pc (void *baton
)
2997 struct agent_expr
*expr
= (struct agent_expr
*) baton
;
3002 /* Compile a DWARF location expression to an agent expression.
3004 EXPR is the agent expression we are building.
3005 LOC is the agent value we modify.
3006 ARCH is the architecture.
3007 ADDR_SIZE is the size of addresses, in bytes.
3008 OP_PTR is the start of the location expression.
3009 OP_END is one past the last byte of the location expression.
3011 This will throw an exception for various kinds of errors -- for
3012 example, if the expression cannot be compiled, or if the expression
3016 dwarf2_compile_expr_to_ax (struct agent_expr
*expr
, struct axs_value
*loc
,
3017 struct gdbarch
*arch
, unsigned int addr_size
,
3018 const gdb_byte
*op_ptr
, const gdb_byte
*op_end
,
3019 struct dwarf2_per_cu_data
*per_cu
)
3022 std::vector
<int> dw_labels
, patches
;
3023 const gdb_byte
* const base
= op_ptr
;
3024 const gdb_byte
*previous_piece
= op_ptr
;
3025 enum bfd_endian byte_order
= gdbarch_byte_order (arch
);
3026 ULONGEST bits_collected
= 0;
3027 unsigned int addr_size_bits
= 8 * addr_size
;
3028 int bits_big_endian
= gdbarch_bits_big_endian (arch
);
3030 std::vector
<int> offsets (op_end
- op_ptr
, -1);
3032 /* By default we are making an address. */
3033 loc
->kind
= axs_lvalue_memory
;
3035 while (op_ptr
< op_end
)
3037 enum dwarf_location_atom op
= (enum dwarf_location_atom
) *op_ptr
;
3038 uint64_t uoffset
, reg
;
3042 offsets
[op_ptr
- base
] = expr
->len
;
3045 /* Our basic approach to code generation is to map DWARF
3046 operations directly to AX operations. However, there are
3049 First, DWARF works on address-sized units, but AX always uses
3050 LONGEST. For most operations we simply ignore this
3051 difference; instead we generate sign extensions as needed
3052 before division and comparison operations. It would be nice
3053 to omit the sign extensions, but there is no way to determine
3054 the size of the target's LONGEST. (This code uses the size
3055 of the host LONGEST in some cases -- that is a bug but it is
3058 Second, some DWARF operations cannot be translated to AX.
3059 For these we simply fail. See
3060 http://sourceware.org/bugzilla/show_bug.cgi?id=11662. */
3095 ax_const_l (expr
, op
- DW_OP_lit0
);
3099 uoffset
= extract_unsigned_integer (op_ptr
, addr_size
, byte_order
);
3100 op_ptr
+= addr_size
;
3101 /* Some versions of GCC emit DW_OP_addr before
3102 DW_OP_GNU_push_tls_address. In this case the value is an
3103 index, not an address. We don't support things like
3104 branching between the address and the TLS op. */
3105 if (op_ptr
>= op_end
|| *op_ptr
!= DW_OP_GNU_push_tls_address
)
3106 uoffset
+= dwarf2_per_cu_text_offset (per_cu
);
3107 ax_const_l (expr
, uoffset
);
3111 ax_const_l (expr
, extract_unsigned_integer (op_ptr
, 1, byte_order
));
3115 ax_const_l (expr
, extract_signed_integer (op_ptr
, 1, byte_order
));
3119 ax_const_l (expr
, extract_unsigned_integer (op_ptr
, 2, byte_order
));
3123 ax_const_l (expr
, extract_signed_integer (op_ptr
, 2, byte_order
));
3127 ax_const_l (expr
, extract_unsigned_integer (op_ptr
, 4, byte_order
));
3131 ax_const_l (expr
, extract_signed_integer (op_ptr
, 4, byte_order
));
3135 ax_const_l (expr
, extract_unsigned_integer (op_ptr
, 8, byte_order
));
3139 ax_const_l (expr
, extract_signed_integer (op_ptr
, 8, byte_order
));
3143 op_ptr
= safe_read_uleb128 (op_ptr
, op_end
, &uoffset
);
3144 ax_const_l (expr
, uoffset
);
3147 op_ptr
= safe_read_sleb128 (op_ptr
, op_end
, &offset
);
3148 ax_const_l (expr
, offset
);
3183 dwarf_expr_require_composition (op_ptr
, op_end
, "DW_OP_regx");
3184 loc
->u
.reg
= dwarf_reg_to_regnum_or_error (arch
, op
- DW_OP_reg0
);
3185 loc
->kind
= axs_lvalue_register
;
3189 op_ptr
= safe_read_uleb128 (op_ptr
, op_end
, ®
);
3190 dwarf_expr_require_composition (op_ptr
, op_end
, "DW_OP_regx");
3191 loc
->u
.reg
= dwarf_reg_to_regnum_or_error (arch
, reg
);
3192 loc
->kind
= axs_lvalue_register
;
3195 case DW_OP_implicit_value
:
3199 op_ptr
= safe_read_uleb128 (op_ptr
, op_end
, &len
);
3200 if (op_ptr
+ len
> op_end
)
3201 error (_("DW_OP_implicit_value: too few bytes available."));
3202 if (len
> sizeof (ULONGEST
))
3203 error (_("Cannot translate DW_OP_implicit_value of %d bytes"),
3206 ax_const_l (expr
, extract_unsigned_integer (op_ptr
, len
,
3209 dwarf_expr_require_composition (op_ptr
, op_end
,
3210 "DW_OP_implicit_value");
3212 loc
->kind
= axs_rvalue
;
3216 case DW_OP_stack_value
:
3217 dwarf_expr_require_composition (op_ptr
, op_end
, "DW_OP_stack_value");
3218 loc
->kind
= axs_rvalue
;
3253 op_ptr
= safe_read_sleb128 (op_ptr
, op_end
, &offset
);
3254 i
= dwarf_reg_to_regnum_or_error (arch
, op
- DW_OP_breg0
);
3258 ax_const_l (expr
, offset
);
3259 ax_simple (expr
, aop_add
);
3264 op_ptr
= safe_read_uleb128 (op_ptr
, op_end
, ®
);
3265 op_ptr
= safe_read_sleb128 (op_ptr
, op_end
, &offset
);
3266 i
= dwarf_reg_to_regnum_or_error (arch
, reg
);
3270 ax_const_l (expr
, offset
);
3271 ax_simple (expr
, aop_add
);
3277 const gdb_byte
*datastart
;
3279 const struct block
*b
;
3280 struct symbol
*framefunc
;
3282 b
= block_for_pc (expr
->scope
);
3285 error (_("No block found for address"));
3287 framefunc
= block_linkage_function (b
);
3290 error (_("No function found for block"));
3292 func_get_frame_base_dwarf_block (framefunc
, expr
->scope
,
3293 &datastart
, &datalen
);
3295 op_ptr
= safe_read_sleb128 (op_ptr
, op_end
, &offset
);
3296 dwarf2_compile_expr_to_ax (expr
, loc
, arch
, addr_size
, datastart
,
3297 datastart
+ datalen
, per_cu
);
3298 if (loc
->kind
== axs_lvalue_register
)
3299 require_rvalue (expr
, loc
);
3303 ax_const_l (expr
, offset
);
3304 ax_simple (expr
, aop_add
);
3307 loc
->kind
= axs_lvalue_memory
;
3312 ax_simple (expr
, aop_dup
);
3316 ax_simple (expr
, aop_pop
);
3321 ax_pick (expr
, offset
);
3325 ax_simple (expr
, aop_swap
);
3333 ax_simple (expr
, aop_rot
);
3337 case DW_OP_deref_size
:
3341 if (op
== DW_OP_deref_size
)
3346 if (size
!= 1 && size
!= 2 && size
!= 4 && size
!= 8)
3347 error (_("Unsupported size %d in %s"),
3348 size
, get_DW_OP_name (op
));
3349 access_memory (arch
, expr
, size
* TARGET_CHAR_BIT
);
3354 /* Sign extend the operand. */
3355 ax_ext (expr
, addr_size_bits
);
3356 ax_simple (expr
, aop_dup
);
3357 ax_const_l (expr
, 0);
3358 ax_simple (expr
, aop_less_signed
);
3359 ax_simple (expr
, aop_log_not
);
3360 i
= ax_goto (expr
, aop_if_goto
);
3361 /* We have to emit 0 - X. */
3362 ax_const_l (expr
, 0);
3363 ax_simple (expr
, aop_swap
);
3364 ax_simple (expr
, aop_sub
);
3365 ax_label (expr
, i
, expr
->len
);
3369 /* No need to sign extend here. */
3370 ax_const_l (expr
, 0);
3371 ax_simple (expr
, aop_swap
);
3372 ax_simple (expr
, aop_sub
);
3376 /* Sign extend the operand. */
3377 ax_ext (expr
, addr_size_bits
);
3378 ax_simple (expr
, aop_bit_not
);
3381 case DW_OP_plus_uconst
:
3382 op_ptr
= safe_read_uleb128 (op_ptr
, op_end
, ®
);
3383 /* It would be really weird to emit `DW_OP_plus_uconst 0',
3384 but we micro-optimize anyhow. */
3387 ax_const_l (expr
, reg
);
3388 ax_simple (expr
, aop_add
);
3393 ax_simple (expr
, aop_bit_and
);
3397 /* Sign extend the operands. */
3398 ax_ext (expr
, addr_size_bits
);
3399 ax_simple (expr
, aop_swap
);
3400 ax_ext (expr
, addr_size_bits
);
3401 ax_simple (expr
, aop_swap
);
3402 ax_simple (expr
, aop_div_signed
);
3406 ax_simple (expr
, aop_sub
);
3410 ax_simple (expr
, aop_rem_unsigned
);
3414 ax_simple (expr
, aop_mul
);
3418 ax_simple (expr
, aop_bit_or
);
3422 ax_simple (expr
, aop_add
);
3426 ax_simple (expr
, aop_lsh
);
3430 ax_simple (expr
, aop_rsh_unsigned
);
3434 ax_simple (expr
, aop_rsh_signed
);
3438 ax_simple (expr
, aop_bit_xor
);
3442 /* Sign extend the operands. */
3443 ax_ext (expr
, addr_size_bits
);
3444 ax_simple (expr
, aop_swap
);
3445 ax_ext (expr
, addr_size_bits
);
3446 /* Note no swap here: A <= B is !(B < A). */
3447 ax_simple (expr
, aop_less_signed
);
3448 ax_simple (expr
, aop_log_not
);
3452 /* Sign extend the operands. */
3453 ax_ext (expr
, addr_size_bits
);
3454 ax_simple (expr
, aop_swap
);
3455 ax_ext (expr
, addr_size_bits
);
3456 ax_simple (expr
, aop_swap
);
3457 /* A >= B is !(A < B). */
3458 ax_simple (expr
, aop_less_signed
);
3459 ax_simple (expr
, aop_log_not
);
3463 /* Sign extend the operands. */
3464 ax_ext (expr
, addr_size_bits
);
3465 ax_simple (expr
, aop_swap
);
3466 ax_ext (expr
, addr_size_bits
);
3467 /* No need for a second swap here. */
3468 ax_simple (expr
, aop_equal
);
3472 /* Sign extend the operands. */
3473 ax_ext (expr
, addr_size_bits
);
3474 ax_simple (expr
, aop_swap
);
3475 ax_ext (expr
, addr_size_bits
);
3476 ax_simple (expr
, aop_swap
);
3477 ax_simple (expr
, aop_less_signed
);
3481 /* Sign extend the operands. */
3482 ax_ext (expr
, addr_size_bits
);
3483 ax_simple (expr
, aop_swap
);
3484 ax_ext (expr
, addr_size_bits
);
3485 /* Note no swap here: A > B is B < A. */
3486 ax_simple (expr
, aop_less_signed
);
3490 /* Sign extend the operands. */
3491 ax_ext (expr
, addr_size_bits
);
3492 ax_simple (expr
, aop_swap
);
3493 ax_ext (expr
, addr_size_bits
);
3494 /* No need for a swap here. */
3495 ax_simple (expr
, aop_equal
);
3496 ax_simple (expr
, aop_log_not
);
3499 case DW_OP_call_frame_cfa
:
3502 CORE_ADDR text_offset
;
3504 const gdb_byte
*cfa_start
, *cfa_end
;
3506 if (dwarf2_fetch_cfa_info (arch
, expr
->scope
, per_cu
,
3508 &text_offset
, &cfa_start
, &cfa_end
))
3511 ax_reg (expr
, regnum
);
3514 ax_const_l (expr
, off
);
3515 ax_simple (expr
, aop_add
);
3520 /* Another expression. */
3521 ax_const_l (expr
, text_offset
);
3522 dwarf2_compile_expr_to_ax (expr
, loc
, arch
, addr_size
,
3523 cfa_start
, cfa_end
, per_cu
);
3526 loc
->kind
= axs_lvalue_memory
;
3530 case DW_OP_GNU_push_tls_address
:
3531 case DW_OP_form_tls_address
:
3535 case DW_OP_push_object_address
:
3540 offset
= extract_signed_integer (op_ptr
, 2, byte_order
);
3542 i
= ax_goto (expr
, aop_goto
);
3543 dw_labels
.push_back (op_ptr
+ offset
- base
);
3544 patches
.push_back (i
);
3548 offset
= extract_signed_integer (op_ptr
, 2, byte_order
);
3550 /* Zero extend the operand. */
3551 ax_zero_ext (expr
, addr_size_bits
);
3552 i
= ax_goto (expr
, aop_if_goto
);
3553 dw_labels
.push_back (op_ptr
+ offset
- base
);
3554 patches
.push_back (i
);
3561 case DW_OP_bit_piece
:
3563 uint64_t size
, offset
;
3565 if (op_ptr
- 1 == previous_piece
)
3566 error (_("Cannot translate empty pieces to agent expressions"));
3567 previous_piece
= op_ptr
- 1;
3569 op_ptr
= safe_read_uleb128 (op_ptr
, op_end
, &size
);
3570 if (op
== DW_OP_piece
)
3576 op_ptr
= safe_read_uleb128 (op_ptr
, op_end
, &offset
);
3578 if (bits_collected
+ size
> 8 * sizeof (LONGEST
))
3579 error (_("Expression pieces exceed word size"));
3581 /* Access the bits. */
3584 case axs_lvalue_register
:
3585 ax_reg (expr
, loc
->u
.reg
);
3588 case axs_lvalue_memory
:
3589 /* Offset the pointer, if needed. */
3592 ax_const_l (expr
, offset
/ 8);
3593 ax_simple (expr
, aop_add
);
3596 access_memory (arch
, expr
, size
);
3600 /* For a bits-big-endian target, shift up what we already
3601 have. For a bits-little-endian target, shift up the
3602 new data. Note that there is a potential bug here if
3603 the DWARF expression leaves multiple values on the
3605 if (bits_collected
> 0)
3607 if (bits_big_endian
)
3609 ax_simple (expr
, aop_swap
);
3610 ax_const_l (expr
, size
);
3611 ax_simple (expr
, aop_lsh
);
3612 /* We don't need a second swap here, because
3613 aop_bit_or is symmetric. */
3617 ax_const_l (expr
, size
);
3618 ax_simple (expr
, aop_lsh
);
3620 ax_simple (expr
, aop_bit_or
);
3623 bits_collected
+= size
;
3624 loc
->kind
= axs_rvalue
;
3628 case DW_OP_GNU_uninit
:
3634 struct dwarf2_locexpr_baton block
;
3635 int size
= (op
== DW_OP_call2
? 2 : 4);
3637 uoffset
= extract_unsigned_integer (op_ptr
, size
, byte_order
);
3640 cu_offset offset
= (cu_offset
) uoffset
;
3641 block
= dwarf2_fetch_die_loc_cu_off (offset
, per_cu
,
3644 /* DW_OP_call_ref is currently not supported. */
3645 gdb_assert (block
.per_cu
== per_cu
);
3647 dwarf2_compile_expr_to_ax (expr
, loc
, arch
, addr_size
,
3648 block
.data
, block
.data
+ block
.size
,
3653 case DW_OP_call_ref
:
3661 /* Patch all the branches we emitted. */
3662 for (i
= 0; i
< patches
.size (); ++i
)
3664 int targ
= offsets
[dw_labels
[i
]];
3666 internal_error (__FILE__
, __LINE__
, _("invalid label"));
3667 ax_label (expr
, patches
[i
], targ
);
3672 /* Return the value of SYMBOL in FRAME using the DWARF-2 expression
3673 evaluator to calculate the location. */
3674 static struct value
*
3675 locexpr_read_variable (struct symbol
*symbol
, struct frame_info
*frame
)
3677 struct dwarf2_locexpr_baton
*dlbaton
3678 = (struct dwarf2_locexpr_baton
*) SYMBOL_LOCATION_BATON (symbol
);
3681 val
= dwarf2_evaluate_loc_desc (SYMBOL_TYPE (symbol
), frame
, dlbaton
->data
,
3682 dlbaton
->size
, dlbaton
->per_cu
);
3687 /* Return the value of SYMBOL in FRAME at (callee) FRAME's function
3688 entry. SYMBOL should be a function parameter, otherwise NO_ENTRY_VALUE_ERROR
3691 static struct value
*
3692 locexpr_read_variable_at_entry (struct symbol
*symbol
, struct frame_info
*frame
)
3694 struct dwarf2_locexpr_baton
*dlbaton
3695 = (struct dwarf2_locexpr_baton
*) SYMBOL_LOCATION_BATON (symbol
);
3697 return value_of_dwarf_block_entry (SYMBOL_TYPE (symbol
), frame
, dlbaton
->data
,
3701 /* Implementation of get_symbol_read_needs from
3702 symbol_computed_ops. */
3704 static enum symbol_needs_kind
3705 locexpr_get_symbol_read_needs (struct symbol
*symbol
)
3707 struct dwarf2_locexpr_baton
*dlbaton
3708 = (struct dwarf2_locexpr_baton
*) SYMBOL_LOCATION_BATON (symbol
);
3710 return dwarf2_loc_desc_get_symbol_read_needs (dlbaton
->data
, dlbaton
->size
,
3714 /* Return true if DATA points to the end of a piece. END is one past
3715 the last byte in the expression. */
3718 piece_end_p (const gdb_byte
*data
, const gdb_byte
*end
)
3720 return data
== end
|| data
[0] == DW_OP_piece
|| data
[0] == DW_OP_bit_piece
;
3723 /* Helper for locexpr_describe_location_piece that finds the name of a
3727 locexpr_regname (struct gdbarch
*gdbarch
, int dwarf_regnum
)
3731 /* This doesn't use dwarf_reg_to_regnum_or_error on purpose.
3732 We'd rather print *something* here than throw an error. */
3733 regnum
= dwarf_reg_to_regnum (gdbarch
, dwarf_regnum
);
3734 /* gdbarch_register_name may just return "", return something more
3735 descriptive for bad register numbers. */
3738 /* The text is output as "$bad_register_number".
3739 That is why we use the underscores. */
3740 return _("bad_register_number");
3742 return gdbarch_register_name (gdbarch
, regnum
);
3745 /* Nicely describe a single piece of a location, returning an updated
3746 position in the bytecode sequence. This function cannot recognize
3747 all locations; if a location is not recognized, it simply returns
3748 DATA. If there is an error during reading, e.g. we run off the end
3749 of the buffer, an error is thrown. */
3751 static const gdb_byte
*
3752 locexpr_describe_location_piece (struct symbol
*symbol
, struct ui_file
*stream
,
3753 CORE_ADDR addr
, struct objfile
*objfile
,
3754 struct dwarf2_per_cu_data
*per_cu
,
3755 const gdb_byte
*data
, const gdb_byte
*end
,
3756 unsigned int addr_size
)
3758 struct gdbarch
*gdbarch
= get_objfile_arch (objfile
);
3761 if (data
[0] >= DW_OP_reg0
&& data
[0] <= DW_OP_reg31
)
3763 fprintf_filtered (stream
, _("a variable in $%s"),
3764 locexpr_regname (gdbarch
, data
[0] - DW_OP_reg0
));
3767 else if (data
[0] == DW_OP_regx
)
3771 data
= safe_read_uleb128 (data
+ 1, end
, ®
);
3772 fprintf_filtered (stream
, _("a variable in $%s"),
3773 locexpr_regname (gdbarch
, reg
));
3775 else if (data
[0] == DW_OP_fbreg
)
3777 const struct block
*b
;
3778 struct symbol
*framefunc
;
3780 int64_t frame_offset
;
3781 const gdb_byte
*base_data
, *new_data
, *save_data
= data
;
3783 int64_t base_offset
= 0;
3785 new_data
= safe_read_sleb128 (data
+ 1, end
, &frame_offset
);
3786 if (!piece_end_p (new_data
, end
))
3790 b
= block_for_pc (addr
);
3793 error (_("No block found for address for symbol \"%s\"."),
3794 SYMBOL_PRINT_NAME (symbol
));
3796 framefunc
= block_linkage_function (b
);
3799 error (_("No function found for block for symbol \"%s\"."),
3800 SYMBOL_PRINT_NAME (symbol
));
3802 func_get_frame_base_dwarf_block (framefunc
, addr
, &base_data
, &base_size
);
3804 if (base_data
[0] >= DW_OP_breg0
&& base_data
[0] <= DW_OP_breg31
)
3806 const gdb_byte
*buf_end
;
3808 frame_reg
= base_data
[0] - DW_OP_breg0
;
3809 buf_end
= safe_read_sleb128 (base_data
+ 1, base_data
+ base_size
,
3811 if (buf_end
!= base_data
+ base_size
)
3812 error (_("Unexpected opcode after "
3813 "DW_OP_breg%u for symbol \"%s\"."),
3814 frame_reg
, SYMBOL_PRINT_NAME (symbol
));
3816 else if (base_data
[0] >= DW_OP_reg0
&& base_data
[0] <= DW_OP_reg31
)
3818 /* The frame base is just the register, with no offset. */
3819 frame_reg
= base_data
[0] - DW_OP_reg0
;
3824 /* We don't know what to do with the frame base expression,
3825 so we can't trace this variable; give up. */
3829 fprintf_filtered (stream
,
3830 _("a variable at frame base reg $%s offset %s+%s"),
3831 locexpr_regname (gdbarch
, frame_reg
),
3832 plongest (base_offset
), plongest (frame_offset
));
3834 else if (data
[0] >= DW_OP_breg0
&& data
[0] <= DW_OP_breg31
3835 && piece_end_p (data
, end
))
3839 data
= safe_read_sleb128 (data
+ 1, end
, &offset
);
3841 fprintf_filtered (stream
,
3842 _("a variable at offset %s from base reg $%s"),
3844 locexpr_regname (gdbarch
, data
[0] - DW_OP_breg0
));
3847 /* The location expression for a TLS variable looks like this (on a
3850 DW_AT_location : 10 byte block: 3 4 0 0 0 0 0 0 0 e0
3851 (DW_OP_addr: 4; DW_OP_GNU_push_tls_address)
3853 0x3 is the encoding for DW_OP_addr, which has an operand as long
3854 as the size of an address on the target machine (here is 8
3855 bytes). Note that more recent version of GCC emit DW_OP_const4u
3856 or DW_OP_const8u, depending on address size, rather than
3857 DW_OP_addr. 0xe0 is the encoding for DW_OP_GNU_push_tls_address.
3858 The operand represents the offset at which the variable is within
3859 the thread local storage. */
3861 else if (data
+ 1 + addr_size
< end
3862 && (data
[0] == DW_OP_addr
3863 || (addr_size
== 4 && data
[0] == DW_OP_const4u
)
3864 || (addr_size
== 8 && data
[0] == DW_OP_const8u
))
3865 && (data
[1 + addr_size
] == DW_OP_GNU_push_tls_address
3866 || data
[1 + addr_size
] == DW_OP_form_tls_address
)
3867 && piece_end_p (data
+ 2 + addr_size
, end
))
3870 offset
= extract_unsigned_integer (data
+ 1, addr_size
,
3871 gdbarch_byte_order (gdbarch
));
3873 fprintf_filtered (stream
,
3874 _("a thread-local variable at offset 0x%s "
3875 "in the thread-local storage for `%s'"),
3876 phex_nz (offset
, addr_size
), objfile_name (objfile
));
3878 data
+= 1 + addr_size
+ 1;
3881 /* With -gsplit-dwarf a TLS variable can also look like this:
3882 DW_AT_location : 3 byte block: fc 4 e0
3883 (DW_OP_GNU_const_index: 4;
3884 DW_OP_GNU_push_tls_address) */
3885 else if (data
+ 3 <= end
3886 && data
+ 1 + (leb128_size
= skip_leb128 (data
+ 1, end
)) < end
3887 && data
[0] == DW_OP_GNU_const_index
3889 && (data
[1 + leb128_size
] == DW_OP_GNU_push_tls_address
3890 || data
[1 + leb128_size
] == DW_OP_form_tls_address
)
3891 && piece_end_p (data
+ 2 + leb128_size
, end
))
3895 data
= safe_read_uleb128 (data
+ 1, end
, &offset
);
3896 offset
= dwarf2_read_addr_index (per_cu
, offset
);
3897 fprintf_filtered (stream
,
3898 _("a thread-local variable at offset 0x%s "
3899 "in the thread-local storage for `%s'"),
3900 phex_nz (offset
, addr_size
), objfile_name (objfile
));
3904 else if (data
[0] >= DW_OP_lit0
3905 && data
[0] <= DW_OP_lit31
3907 && data
[1] == DW_OP_stack_value
)
3909 fprintf_filtered (stream
, _("the constant %d"), data
[0] - DW_OP_lit0
);
3916 /* Disassemble an expression, stopping at the end of a piece or at the
3917 end of the expression. Returns a pointer to the next unread byte
3918 in the input expression. If ALL is nonzero, then this function
3919 will keep going until it reaches the end of the expression.
3920 If there is an error during reading, e.g. we run off the end
3921 of the buffer, an error is thrown. */
3923 static const gdb_byte
*
3924 disassemble_dwarf_expression (struct ui_file
*stream
,
3925 struct gdbarch
*arch
, unsigned int addr_size
,
3926 int offset_size
, const gdb_byte
*start
,
3927 const gdb_byte
*data
, const gdb_byte
*end
,
3928 int indent
, int all
,
3929 struct dwarf2_per_cu_data
*per_cu
)
3933 || (data
[0] != DW_OP_piece
&& data
[0] != DW_OP_bit_piece
)))
3935 enum dwarf_location_atom op
= (enum dwarf_location_atom
) *data
++;
3940 name
= get_DW_OP_name (op
);
3943 error (_("Unrecognized DWARF opcode 0x%02x at %ld"),
3944 op
, (long) (data
- 1 - start
));
3945 fprintf_filtered (stream
, " %*ld: %s", indent
+ 4,
3946 (long) (data
- 1 - start
), name
);
3951 ul
= extract_unsigned_integer (data
, addr_size
,
3952 gdbarch_byte_order (arch
));
3954 fprintf_filtered (stream
, " 0x%s", phex_nz (ul
, addr_size
));
3958 ul
= extract_unsigned_integer (data
, 1, gdbarch_byte_order (arch
));
3960 fprintf_filtered (stream
, " %s", pulongest (ul
));
3963 l
= extract_signed_integer (data
, 1, gdbarch_byte_order (arch
));
3965 fprintf_filtered (stream
, " %s", plongest (l
));
3968 ul
= extract_unsigned_integer (data
, 2, gdbarch_byte_order (arch
));
3970 fprintf_filtered (stream
, " %s", pulongest (ul
));
3973 l
= extract_signed_integer (data
, 2, gdbarch_byte_order (arch
));
3975 fprintf_filtered (stream
, " %s", plongest (l
));
3978 ul
= extract_unsigned_integer (data
, 4, gdbarch_byte_order (arch
));
3980 fprintf_filtered (stream
, " %s", pulongest (ul
));
3983 l
= extract_signed_integer (data
, 4, gdbarch_byte_order (arch
));
3985 fprintf_filtered (stream
, " %s", plongest (l
));
3988 ul
= extract_unsigned_integer (data
, 8, gdbarch_byte_order (arch
));
3990 fprintf_filtered (stream
, " %s", pulongest (ul
));
3993 l
= extract_signed_integer (data
, 8, gdbarch_byte_order (arch
));
3995 fprintf_filtered (stream
, " %s", plongest (l
));
3998 data
= safe_read_uleb128 (data
, end
, &ul
);
3999 fprintf_filtered (stream
, " %s", pulongest (ul
));
4002 data
= safe_read_sleb128 (data
, end
, &l
);
4003 fprintf_filtered (stream
, " %s", plongest (l
));
4038 fprintf_filtered (stream
, " [$%s]",
4039 locexpr_regname (arch
, op
- DW_OP_reg0
));
4043 data
= safe_read_uleb128 (data
, end
, &ul
);
4044 fprintf_filtered (stream
, " %s [$%s]", pulongest (ul
),
4045 locexpr_regname (arch
, (int) ul
));
4048 case DW_OP_implicit_value
:
4049 data
= safe_read_uleb128 (data
, end
, &ul
);
4051 fprintf_filtered (stream
, " %s", pulongest (ul
));
4086 data
= safe_read_sleb128 (data
, end
, &l
);
4087 fprintf_filtered (stream
, " %s [$%s]", plongest (l
),
4088 locexpr_regname (arch
, op
- DW_OP_breg0
));
4092 data
= safe_read_uleb128 (data
, end
, &ul
);
4093 data
= safe_read_sleb128 (data
, end
, &l
);
4094 fprintf_filtered (stream
, " register %s [$%s] offset %s",
4096 locexpr_regname (arch
, (int) ul
),
4101 data
= safe_read_sleb128 (data
, end
, &l
);
4102 fprintf_filtered (stream
, " %s", plongest (l
));
4105 case DW_OP_xderef_size
:
4106 case DW_OP_deref_size
:
4108 fprintf_filtered (stream
, " %d", *data
);
4112 case DW_OP_plus_uconst
:
4113 data
= safe_read_uleb128 (data
, end
, &ul
);
4114 fprintf_filtered (stream
, " %s", pulongest (ul
));
4118 l
= extract_signed_integer (data
, 2, gdbarch_byte_order (arch
));
4120 fprintf_filtered (stream
, " to %ld",
4121 (long) (data
+ l
- start
));
4125 l
= extract_signed_integer (data
, 2, gdbarch_byte_order (arch
));
4127 fprintf_filtered (stream
, " %ld",
4128 (long) (data
+ l
- start
));
4132 ul
= extract_unsigned_integer (data
, 2, gdbarch_byte_order (arch
));
4134 fprintf_filtered (stream
, " offset %s", phex_nz (ul
, 2));
4138 ul
= extract_unsigned_integer (data
, 4, gdbarch_byte_order (arch
));
4140 fprintf_filtered (stream
, " offset %s", phex_nz (ul
, 4));
4143 case DW_OP_call_ref
:
4144 ul
= extract_unsigned_integer (data
, offset_size
,
4145 gdbarch_byte_order (arch
));
4146 data
+= offset_size
;
4147 fprintf_filtered (stream
, " offset %s", phex_nz (ul
, offset_size
));
4151 data
= safe_read_uleb128 (data
, end
, &ul
);
4152 fprintf_filtered (stream
, " %s (bytes)", pulongest (ul
));
4155 case DW_OP_bit_piece
:
4159 data
= safe_read_uleb128 (data
, end
, &ul
);
4160 data
= safe_read_uleb128 (data
, end
, &offset
);
4161 fprintf_filtered (stream
, " size %s offset %s (bits)",
4162 pulongest (ul
), pulongest (offset
));
4166 case DW_OP_implicit_pointer
:
4167 case DW_OP_GNU_implicit_pointer
:
4169 ul
= extract_unsigned_integer (data
, offset_size
,
4170 gdbarch_byte_order (arch
));
4171 data
+= offset_size
;
4173 data
= safe_read_sleb128 (data
, end
, &l
);
4175 fprintf_filtered (stream
, " DIE %s offset %s",
4176 phex_nz (ul
, offset_size
),
4181 case DW_OP_deref_type
:
4182 case DW_OP_GNU_deref_type
:
4184 int addr_size
= *data
++;
4187 data
= safe_read_uleb128 (data
, end
, &ul
);
4188 cu_offset offset
= (cu_offset
) ul
;
4189 type
= dwarf2_get_die_type (offset
, per_cu
);
4190 fprintf_filtered (stream
, "<");
4191 type_print (type
, "", stream
, -1);
4192 fprintf_filtered (stream
, " [0x%s]> %d",
4193 phex_nz (to_underlying (offset
), 0),
4198 case DW_OP_const_type
:
4199 case DW_OP_GNU_const_type
:
4203 data
= safe_read_uleb128 (data
, end
, &ul
);
4204 cu_offset type_die
= (cu_offset
) ul
;
4205 type
= dwarf2_get_die_type (type_die
, per_cu
);
4206 fprintf_filtered (stream
, "<");
4207 type_print (type
, "", stream
, -1);
4208 fprintf_filtered (stream
, " [0x%s]>",
4209 phex_nz (to_underlying (type_die
), 0));
4213 case DW_OP_regval_type
:
4214 case DW_OP_GNU_regval_type
:
4219 data
= safe_read_uleb128 (data
, end
, ®
);
4220 data
= safe_read_uleb128 (data
, end
, &ul
);
4221 cu_offset type_die
= (cu_offset
) ul
;
4223 type
= dwarf2_get_die_type (type_die
, per_cu
);
4224 fprintf_filtered (stream
, "<");
4225 type_print (type
, "", stream
, -1);
4226 fprintf_filtered (stream
, " [0x%s]> [$%s]",
4227 phex_nz (to_underlying (type_die
), 0),
4228 locexpr_regname (arch
, reg
));
4233 case DW_OP_GNU_convert
:
4234 case DW_OP_reinterpret
:
4235 case DW_OP_GNU_reinterpret
:
4237 data
= safe_read_uleb128 (data
, end
, &ul
);
4238 cu_offset type_die
= (cu_offset
) ul
;
4240 if (to_underlying (type_die
) == 0)
4241 fprintf_filtered (stream
, "<0>");
4246 type
= dwarf2_get_die_type (type_die
, per_cu
);
4247 fprintf_filtered (stream
, "<");
4248 type_print (type
, "", stream
, -1);
4249 fprintf_filtered (stream
, " [0x%s]>",
4250 phex_nz (to_underlying (type_die
), 0));
4255 case DW_OP_entry_value
:
4256 case DW_OP_GNU_entry_value
:
4257 data
= safe_read_uleb128 (data
, end
, &ul
);
4258 fputc_filtered ('\n', stream
);
4259 disassemble_dwarf_expression (stream
, arch
, addr_size
, offset_size
,
4260 start
, data
, data
+ ul
, indent
+ 2,
4265 case DW_OP_GNU_parameter_ref
:
4266 ul
= extract_unsigned_integer (data
, 4, gdbarch_byte_order (arch
));
4268 fprintf_filtered (stream
, " offset %s", phex_nz (ul
, 4));
4271 case DW_OP_GNU_addr_index
:
4272 data
= safe_read_uleb128 (data
, end
, &ul
);
4273 ul
= dwarf2_read_addr_index (per_cu
, ul
);
4274 fprintf_filtered (stream
, " 0x%s", phex_nz (ul
, addr_size
));
4276 case DW_OP_GNU_const_index
:
4277 data
= safe_read_uleb128 (data
, end
, &ul
);
4278 ul
= dwarf2_read_addr_index (per_cu
, ul
);
4279 fprintf_filtered (stream
, " %s", pulongest (ul
));
4283 fprintf_filtered (stream
, "\n");
4289 /* Describe a single location, which may in turn consist of multiple
4293 locexpr_describe_location_1 (struct symbol
*symbol
, CORE_ADDR addr
,
4294 struct ui_file
*stream
,
4295 const gdb_byte
*data
, size_t size
,
4296 struct objfile
*objfile
, unsigned int addr_size
,
4297 int offset_size
, struct dwarf2_per_cu_data
*per_cu
)
4299 const gdb_byte
*end
= data
+ size
;
4300 int first_piece
= 1, bad
= 0;
4304 const gdb_byte
*here
= data
;
4305 int disassemble
= 1;
4310 fprintf_filtered (stream
, _(", and "));
4312 if (!dwarf_always_disassemble
)
4314 data
= locexpr_describe_location_piece (symbol
, stream
,
4315 addr
, objfile
, per_cu
,
4316 data
, end
, addr_size
);
4317 /* If we printed anything, or if we have an empty piece,
4318 then don't disassemble. */
4320 || data
[0] == DW_OP_piece
4321 || data
[0] == DW_OP_bit_piece
)
4326 fprintf_filtered (stream
, _("a complex DWARF expression:\n"));
4327 data
= disassemble_dwarf_expression (stream
,
4328 get_objfile_arch (objfile
),
4329 addr_size
, offset_size
, data
,
4331 dwarf_always_disassemble
,
4337 int empty
= data
== here
;
4340 fprintf_filtered (stream
, " ");
4341 if (data
[0] == DW_OP_piece
)
4345 data
= safe_read_uleb128 (data
+ 1, end
, &bytes
);
4348 fprintf_filtered (stream
, _("an empty %s-byte piece"),
4351 fprintf_filtered (stream
, _(" [%s-byte piece]"),
4354 else if (data
[0] == DW_OP_bit_piece
)
4356 uint64_t bits
, offset
;
4358 data
= safe_read_uleb128 (data
+ 1, end
, &bits
);
4359 data
= safe_read_uleb128 (data
, end
, &offset
);
4362 fprintf_filtered (stream
,
4363 _("an empty %s-bit piece"),
4366 fprintf_filtered (stream
,
4367 _(" [%s-bit piece, offset %s bits]"),
4368 pulongest (bits
), pulongest (offset
));
4378 if (bad
|| data
> end
)
4379 error (_("Corrupted DWARF2 expression for \"%s\"."),
4380 SYMBOL_PRINT_NAME (symbol
));
4383 /* Print a natural-language description of SYMBOL to STREAM. This
4384 version is for a symbol with a single location. */
4387 locexpr_describe_location (struct symbol
*symbol
, CORE_ADDR addr
,
4388 struct ui_file
*stream
)
4390 struct dwarf2_locexpr_baton
*dlbaton
4391 = (struct dwarf2_locexpr_baton
*) SYMBOL_LOCATION_BATON (symbol
);
4392 struct objfile
*objfile
= dwarf2_per_cu_objfile (dlbaton
->per_cu
);
4393 unsigned int addr_size
= dwarf2_per_cu_addr_size (dlbaton
->per_cu
);
4394 int offset_size
= dwarf2_per_cu_offset_size (dlbaton
->per_cu
);
4396 locexpr_describe_location_1 (symbol
, addr
, stream
,
4397 dlbaton
->data
, dlbaton
->size
,
4398 objfile
, addr_size
, offset_size
,
4402 /* Describe the location of SYMBOL as an agent value in VALUE, generating
4403 any necessary bytecode in AX. */
4406 locexpr_tracepoint_var_ref (struct symbol
*symbol
, struct gdbarch
*gdbarch
,
4407 struct agent_expr
*ax
, struct axs_value
*value
)
4409 struct dwarf2_locexpr_baton
*dlbaton
4410 = (struct dwarf2_locexpr_baton
*) SYMBOL_LOCATION_BATON (symbol
);
4411 unsigned int addr_size
= dwarf2_per_cu_addr_size (dlbaton
->per_cu
);
4413 if (dlbaton
->size
== 0)
4414 value
->optimized_out
= 1;
4416 dwarf2_compile_expr_to_ax (ax
, value
, gdbarch
, addr_size
,
4417 dlbaton
->data
, dlbaton
->data
+ dlbaton
->size
,
4421 /* symbol_computed_ops 'generate_c_location' method. */
4424 locexpr_generate_c_location (struct symbol
*sym
, string_file
&stream
,
4425 struct gdbarch
*gdbarch
,
4426 unsigned char *registers_used
,
4427 CORE_ADDR pc
, const char *result_name
)
4429 struct dwarf2_locexpr_baton
*dlbaton
4430 = (struct dwarf2_locexpr_baton
*) SYMBOL_LOCATION_BATON (sym
);
4431 unsigned int addr_size
= dwarf2_per_cu_addr_size (dlbaton
->per_cu
);
4433 if (dlbaton
->size
== 0)
4434 error (_("symbol \"%s\" is optimized out"), SYMBOL_NATURAL_NAME (sym
));
4436 compile_dwarf_expr_to_c (stream
, result_name
,
4437 sym
, pc
, gdbarch
, registers_used
, addr_size
,
4438 dlbaton
->data
, dlbaton
->data
+ dlbaton
->size
,
4442 /* The set of location functions used with the DWARF-2 expression
4444 const struct symbol_computed_ops dwarf2_locexpr_funcs
= {
4445 locexpr_read_variable
,
4446 locexpr_read_variable_at_entry
,
4447 locexpr_get_symbol_read_needs
,
4448 locexpr_describe_location
,
4449 0, /* location_has_loclist */
4450 locexpr_tracepoint_var_ref
,
4451 locexpr_generate_c_location
4455 /* Wrapper functions for location lists. These generally find
4456 the appropriate location expression and call something above. */
4458 /* Return the value of SYMBOL in FRAME using the DWARF-2 expression
4459 evaluator to calculate the location. */
4460 static struct value
*
4461 loclist_read_variable (struct symbol
*symbol
, struct frame_info
*frame
)
4463 struct dwarf2_loclist_baton
*dlbaton
4464 = (struct dwarf2_loclist_baton
*) SYMBOL_LOCATION_BATON (symbol
);
4466 const gdb_byte
*data
;
4468 CORE_ADDR pc
= frame
? get_frame_address_in_block (frame
) : 0;
4470 data
= dwarf2_find_location_expression (dlbaton
, &size
, pc
);
4471 val
= dwarf2_evaluate_loc_desc (SYMBOL_TYPE (symbol
), frame
, data
, size
,
4477 /* Read variable SYMBOL like loclist_read_variable at (callee) FRAME's function
4478 entry. SYMBOL should be a function parameter, otherwise NO_ENTRY_VALUE_ERROR
4481 Function always returns non-NULL value, it may be marked optimized out if
4482 inferior frame information is not available. It throws NO_ENTRY_VALUE_ERROR
4483 if it cannot resolve the parameter for any reason. */
4485 static struct value
*
4486 loclist_read_variable_at_entry (struct symbol
*symbol
, struct frame_info
*frame
)
4488 struct dwarf2_loclist_baton
*dlbaton
4489 = (struct dwarf2_loclist_baton
*) SYMBOL_LOCATION_BATON (symbol
);
4490 const gdb_byte
*data
;
4494 if (frame
== NULL
|| !get_frame_func_if_available (frame
, &pc
))
4495 return allocate_optimized_out_value (SYMBOL_TYPE (symbol
));
4497 data
= dwarf2_find_location_expression (dlbaton
, &size
, pc
);
4499 return allocate_optimized_out_value (SYMBOL_TYPE (symbol
));
4501 return value_of_dwarf_block_entry (SYMBOL_TYPE (symbol
), frame
, data
, size
);
4504 /* Implementation of get_symbol_read_needs from
4505 symbol_computed_ops. */
4507 static enum symbol_needs_kind
4508 loclist_symbol_needs (struct symbol
*symbol
)
4510 /* If there's a location list, then assume we need to have a frame
4511 to choose the appropriate location expression. With tracking of
4512 global variables this is not necessarily true, but such tracking
4513 is disabled in GCC at the moment until we figure out how to
4516 return SYMBOL_NEEDS_FRAME
;
4519 /* Print a natural-language description of SYMBOL to STREAM. This
4520 version applies when there is a list of different locations, each
4521 with a specified address range. */
4524 loclist_describe_location (struct symbol
*symbol
, CORE_ADDR addr
,
4525 struct ui_file
*stream
)
4527 struct dwarf2_loclist_baton
*dlbaton
4528 = (struct dwarf2_loclist_baton
*) SYMBOL_LOCATION_BATON (symbol
);
4529 const gdb_byte
*loc_ptr
, *buf_end
;
4530 struct objfile
*objfile
= dwarf2_per_cu_objfile (dlbaton
->per_cu
);
4531 struct gdbarch
*gdbarch
= get_objfile_arch (objfile
);
4532 enum bfd_endian byte_order
= gdbarch_byte_order (gdbarch
);
4533 unsigned int addr_size
= dwarf2_per_cu_addr_size (dlbaton
->per_cu
);
4534 int offset_size
= dwarf2_per_cu_offset_size (dlbaton
->per_cu
);
4535 int signed_addr_p
= bfd_get_sign_extend_vma (objfile
->obfd
);
4536 /* Adjust base_address for relocatable objects. */
4537 CORE_ADDR base_offset
= dwarf2_per_cu_text_offset (dlbaton
->per_cu
);
4538 CORE_ADDR base_address
= dlbaton
->base_address
+ base_offset
;
4541 loc_ptr
= dlbaton
->data
;
4542 buf_end
= dlbaton
->data
+ dlbaton
->size
;
4544 fprintf_filtered (stream
, _("multi-location:\n"));
4546 /* Iterate through locations until we run out. */
4549 CORE_ADDR low
= 0, high
= 0; /* init for gcc -Wall */
4551 enum debug_loc_kind kind
;
4552 const gdb_byte
*new_ptr
= NULL
; /* init for gcc -Wall */
4554 if (dlbaton
->from_dwo
)
4555 kind
= decode_debug_loc_dwo_addresses (dlbaton
->per_cu
,
4556 loc_ptr
, buf_end
, &new_ptr
,
4557 &low
, &high
, byte_order
);
4559 kind
= decode_debug_loc_addresses (loc_ptr
, buf_end
, &new_ptr
,
4561 byte_order
, addr_size
,
4566 case DEBUG_LOC_END_OF_LIST
:
4569 case DEBUG_LOC_BASE_ADDRESS
:
4570 base_address
= high
+ base_offset
;
4571 fprintf_filtered (stream
, _(" Base address %s"),
4572 paddress (gdbarch
, base_address
));
4574 case DEBUG_LOC_START_END
:
4575 case DEBUG_LOC_START_LENGTH
:
4577 case DEBUG_LOC_BUFFER_OVERFLOW
:
4578 case DEBUG_LOC_INVALID_ENTRY
:
4579 error (_("Corrupted DWARF expression for symbol \"%s\"."),
4580 SYMBOL_PRINT_NAME (symbol
));
4582 gdb_assert_not_reached ("bad debug_loc_kind");
4585 /* Otherwise, a location expression entry. */
4586 low
+= base_address
;
4587 high
+= base_address
;
4589 low
= gdbarch_adjust_dwarf2_addr (gdbarch
, low
);
4590 high
= gdbarch_adjust_dwarf2_addr (gdbarch
, high
);
4592 length
= extract_unsigned_integer (loc_ptr
, 2, byte_order
);
4595 /* (It would improve readability to print only the minimum
4596 necessary digits of the second number of the range.) */
4597 fprintf_filtered (stream
, _(" Range %s-%s: "),
4598 paddress (gdbarch
, low
), paddress (gdbarch
, high
));
4600 /* Now describe this particular location. */
4601 locexpr_describe_location_1 (symbol
, low
, stream
, loc_ptr
, length
,
4602 objfile
, addr_size
, offset_size
,
4605 fprintf_filtered (stream
, "\n");
4611 /* Describe the location of SYMBOL as an agent value in VALUE, generating
4612 any necessary bytecode in AX. */
4614 loclist_tracepoint_var_ref (struct symbol
*symbol
, struct gdbarch
*gdbarch
,
4615 struct agent_expr
*ax
, struct axs_value
*value
)
4617 struct dwarf2_loclist_baton
*dlbaton
4618 = (struct dwarf2_loclist_baton
*) SYMBOL_LOCATION_BATON (symbol
);
4619 const gdb_byte
*data
;
4621 unsigned int addr_size
= dwarf2_per_cu_addr_size (dlbaton
->per_cu
);
4623 data
= dwarf2_find_location_expression (dlbaton
, &size
, ax
->scope
);
4625 value
->optimized_out
= 1;
4627 dwarf2_compile_expr_to_ax (ax
, value
, gdbarch
, addr_size
, data
, data
+ size
,
4631 /* symbol_computed_ops 'generate_c_location' method. */
4634 loclist_generate_c_location (struct symbol
*sym
, string_file
&stream
,
4635 struct gdbarch
*gdbarch
,
4636 unsigned char *registers_used
,
4637 CORE_ADDR pc
, const char *result_name
)
4639 struct dwarf2_loclist_baton
*dlbaton
4640 = (struct dwarf2_loclist_baton
*) SYMBOL_LOCATION_BATON (sym
);
4641 unsigned int addr_size
= dwarf2_per_cu_addr_size (dlbaton
->per_cu
);
4642 const gdb_byte
*data
;
4645 data
= dwarf2_find_location_expression (dlbaton
, &size
, pc
);
4647 error (_("symbol \"%s\" is optimized out"), SYMBOL_NATURAL_NAME (sym
));
4649 compile_dwarf_expr_to_c (stream
, result_name
,
4650 sym
, pc
, gdbarch
, registers_used
, addr_size
,
4655 /* The set of location functions used with the DWARF-2 expression
4656 evaluator and location lists. */
4657 const struct symbol_computed_ops dwarf2_loclist_funcs
= {
4658 loclist_read_variable
,
4659 loclist_read_variable_at_entry
,
4660 loclist_symbol_needs
,
4661 loclist_describe_location
,
4662 1, /* location_has_loclist */
4663 loclist_tracepoint_var_ref
,
4664 loclist_generate_c_location
4667 /* Provide a prototype to silence -Wmissing-prototypes. */
4668 extern initialize_file_ftype _initialize_dwarf2loc
;
4671 _initialize_dwarf2loc (void)
4673 add_setshow_zuinteger_cmd ("entry-values", class_maintenance
,
4674 &entry_values_debug
,
4675 _("Set entry values and tail call frames "
4677 _("Show entry values and tail call frames "
4679 _("When non-zero, the process of determining "
4680 "parameter values from function entry point "
4681 "and tail call frames will be printed."),
4683 show_entry_values_debug
,
4684 &setdebuglist
, &showdebuglist
);
4687 register_self_test (selftests::copy_bitwise_tests
);