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 target address size, used only for DWARF_VALUE_STACK. */
1492 /* The pieces themselves. */
1493 struct dwarf_expr_piece
*pieces
;
1495 /* Frame ID of frame to which a register value is relative, used
1496 only by DWARF_VALUE_REGISTER. */
1497 struct frame_id frame_id
;
1500 /* Allocate a closure for a value formed from separately-described
1503 static struct piece_closure
*
1504 allocate_piece_closure (struct dwarf2_per_cu_data
*per_cu
,
1505 int n_pieces
, struct dwarf_expr_piece
*pieces
,
1506 int addr_size
, struct frame_info
*frame
)
1508 struct piece_closure
*c
= XCNEW (struct piece_closure
);
1513 c
->n_pieces
= n_pieces
;
1514 c
->addr_size
= addr_size
;
1515 c
->pieces
= XCNEWVEC (struct dwarf_expr_piece
, n_pieces
);
1517 c
->frame_id
= null_frame_id
;
1519 c
->frame_id
= get_frame_id (frame
);
1521 memcpy (c
->pieces
, pieces
, n_pieces
* sizeof (struct dwarf_expr_piece
));
1522 for (i
= 0; i
< n_pieces
; ++i
)
1523 if (c
->pieces
[i
].location
== DWARF_VALUE_STACK
)
1524 value_incref (c
->pieces
[i
].v
.value
);
1529 /* Copy NBITS bits from SOURCE to DEST starting at the given bit
1530 offsets. Use the bit order as specified by BITS_BIG_ENDIAN.
1531 Source and destination buffers must not overlap. */
1534 copy_bitwise (gdb_byte
*dest
, ULONGEST dest_offset
,
1535 const gdb_byte
*source
, ULONGEST source_offset
,
1536 ULONGEST nbits
, int bits_big_endian
)
1538 unsigned int buf
, avail
;
1543 if (bits_big_endian
)
1545 /* Start from the end, then work backwards. */
1546 dest_offset
+= nbits
- 1;
1547 dest
+= dest_offset
/ 8;
1548 dest_offset
= 7 - dest_offset
% 8;
1549 source_offset
+= nbits
- 1;
1550 source
+= source_offset
/ 8;
1551 source_offset
= 7 - source_offset
% 8;
1555 dest
+= dest_offset
/ 8;
1557 source
+= source_offset
/ 8;
1561 /* Fill BUF with DEST_OFFSET bits from the destination and 8 -
1562 SOURCE_OFFSET bits from the source. */
1563 buf
= *(bits_big_endian
? source
-- : source
++) >> source_offset
;
1564 buf
<<= dest_offset
;
1565 buf
|= *dest
& ((1 << dest_offset
) - 1);
1567 /* NBITS: bits yet to be written; AVAIL: BUF's fill level. */
1568 nbits
+= dest_offset
;
1569 avail
= dest_offset
+ 8 - source_offset
;
1571 /* Flush 8 bits from BUF, if appropriate. */
1572 if (nbits
>= 8 && avail
>= 8)
1574 *(bits_big_endian
? dest
-- : dest
++) = buf
;
1580 /* Copy the middle part. */
1583 size_t len
= nbits
/ 8;
1585 /* Use a faster method for byte-aligned copies. */
1588 if (bits_big_endian
)
1592 memcpy (dest
+ 1, source
+ 1, len
);
1596 memcpy (dest
, source
, len
);
1605 buf
|= *(bits_big_endian
? source
-- : source
++) << avail
;
1606 *(bits_big_endian
? dest
-- : dest
++) = buf
;
1613 /* Write the last byte. */
1617 buf
|= *source
<< avail
;
1619 buf
&= (1 << nbits
) - 1;
1620 *dest
= (*dest
& (~0 << nbits
)) | buf
;
1626 namespace selftests
{
1628 /* Helper function for the unit test of copy_bitwise. Convert NBITS bits
1629 out of BITS, starting at OFFS, to the respective '0'/'1'-string. MSB0
1630 specifies whether to assume big endian bit numbering. Store the
1631 resulting (not null-terminated) string at STR. */
1634 bits_to_str (char *str
, const gdb_byte
*bits
, ULONGEST offs
,
1635 ULONGEST nbits
, int msb0
)
1640 for (i
= offs
/ 8, j
= offs
% 8; nbits
; i
++, j
= 0)
1642 unsigned int ch
= bits
[i
];
1643 for (; j
< 8 && nbits
; j
++, nbits
--)
1644 *str
++ = (ch
& (msb0
? (1 << (7 - j
)) : (1 << j
))) ? '1' : '0';
1648 /* Check one invocation of copy_bitwise with the given parameters. */
1651 check_copy_bitwise (const gdb_byte
*dest
, unsigned int dest_offset
,
1652 const gdb_byte
*source
, unsigned int source_offset
,
1653 unsigned int nbits
, int msb0
)
1655 size_t len
= align_up (dest_offset
+ nbits
, 8);
1656 char *expected
= (char *) alloca (len
+ 1);
1657 char *actual
= (char *) alloca (len
+ 1);
1658 gdb_byte
*buf
= (gdb_byte
*) alloca (len
/ 8);
1660 /* Compose a '0'/'1'-string that represents the expected result of
1662 Bits from [0, DEST_OFFSET) are filled from DEST.
1663 Bits from [DEST_OFFSET, DEST_OFFSET + NBITS) are filled from SOURCE.
1664 Bits from [DEST_OFFSET + NBITS, LEN) are filled from DEST.
1673 We should end up with:
1675 DDDDSSDD (D=dest, S=source)
1677 bits_to_str (expected
, dest
, 0, len
, msb0
);
1678 bits_to_str (expected
+ dest_offset
, source
, source_offset
, nbits
, msb0
);
1680 /* Fill BUF with data from DEST, apply copy_bitwise, and convert the
1681 result to a '0'/'1'-string. */
1682 memcpy (buf
, dest
, len
/ 8);
1683 copy_bitwise (buf
, dest_offset
, source
, source_offset
, nbits
, msb0
);
1684 bits_to_str (actual
, buf
, 0, len
, msb0
);
1686 /* Compare the resulting strings. */
1687 expected
[len
] = actual
[len
] = '\0';
1688 if (strcmp (expected
, actual
) != 0)
1689 error (_("copy_bitwise %s != %s (%u+%u -> %u)"),
1690 expected
, actual
, source_offset
, nbits
, dest_offset
);
1693 /* Unit test for copy_bitwise. */
1696 copy_bitwise_tests (void)
1698 /* Data to be used as both source and destination buffers. The two
1699 arrays below represent the lsb0- and msb0- encoded versions of the
1700 following bit string, respectively:
1701 00000000 00011111 11111111 01001000 10100101 11110010
1702 This pattern is chosen such that it contains:
1703 - constant 0- and 1- chunks of more than a full byte;
1704 - 0/1- and 1/0 transitions on all bit positions within a byte;
1705 - several sufficiently asymmetric bytes.
1707 static const gdb_byte data_lsb0
[] = {
1708 0x00, 0xf8, 0xff, 0x12, 0xa5, 0x4f
1710 static const gdb_byte data_msb0
[] = {
1711 0x00, 0x1f, 0xff, 0x48, 0xa5, 0xf2
1714 constexpr size_t data_nbits
= 8 * sizeof (data_lsb0
);
1715 constexpr unsigned max_nbits
= 24;
1717 /* Try all combinations of:
1718 lsb0/msb0 bit order (using the respective data array)
1719 X [0, MAX_NBITS] copy bit width
1720 X feasible source offsets for the given copy bit width
1721 X feasible destination offsets
1723 for (int msb0
= 0; msb0
< 2; msb0
++)
1725 const gdb_byte
*data
= msb0
? data_msb0
: data_lsb0
;
1727 for (unsigned int nbits
= 1; nbits
<= max_nbits
; nbits
++)
1729 const unsigned int max_offset
= data_nbits
- nbits
;
1731 for (unsigned source_offset
= 0;
1732 source_offset
<= max_offset
;
1735 for (unsigned dest_offset
= 0;
1736 dest_offset
<= max_offset
;
1739 check_copy_bitwise (data
+ dest_offset
/ 8,
1741 data
+ source_offset
/ 8,
1748 /* Special cases: copy all, copy nothing. */
1749 check_copy_bitwise (data_lsb0
, 0, data_msb0
, 0, data_nbits
, msb0
);
1750 check_copy_bitwise (data_msb0
, 0, data_lsb0
, 0, data_nbits
, msb0
);
1751 check_copy_bitwise (data
, data_nbits
- 7, data
, 9, 0, msb0
);
1755 } /* namespace selftests */
1757 #endif /* GDB_SELF_TEST */
1760 read_pieced_value (struct value
*v
)
1764 ULONGEST bits_to_skip
;
1766 struct piece_closure
*c
1767 = (struct piece_closure
*) value_computed_closure (v
);
1769 size_t buffer_size
= 0;
1770 std::vector
<gdb_byte
> buffer
;
1772 = gdbarch_bits_big_endian (get_type_arch (value_type (v
)));
1774 if (value_type (v
) != value_enclosing_type (v
))
1775 internal_error (__FILE__
, __LINE__
,
1776 _("Should not be able to create a lazy value with "
1777 "an enclosing type"));
1779 contents
= value_contents_raw (v
);
1780 bits_to_skip
= 8 * value_offset (v
);
1781 if (value_bitsize (v
))
1783 bits_to_skip
+= value_bitpos (v
);
1784 type_len
= value_bitsize (v
);
1787 type_len
= 8 * TYPE_LENGTH (value_type (v
));
1789 for (i
= 0; i
< c
->n_pieces
&& offset
< type_len
; i
++)
1791 struct dwarf_expr_piece
*p
= &c
->pieces
[i
];
1792 size_t this_size
, this_size_bits
;
1793 long dest_offset_bits
, source_offset_bits
, source_offset
;
1794 const gdb_byte
*intermediate_buffer
;
1796 /* Compute size, source, and destination offsets for copying, in
1798 this_size_bits
= p
->size
;
1799 if (bits_to_skip
> 0 && bits_to_skip
>= this_size_bits
)
1801 bits_to_skip
-= this_size_bits
;
1804 if (bits_to_skip
> 0)
1806 dest_offset_bits
= 0;
1807 source_offset_bits
= bits_to_skip
;
1808 this_size_bits
-= bits_to_skip
;
1813 dest_offset_bits
= offset
;
1814 source_offset_bits
= 0;
1816 if (this_size_bits
> type_len
- offset
)
1817 this_size_bits
= type_len
- offset
;
1819 this_size
= (this_size_bits
+ source_offset_bits
% 8 + 7) / 8;
1820 source_offset
= source_offset_bits
/ 8;
1821 if (buffer_size
< this_size
)
1823 buffer_size
= this_size
;
1824 buffer
.reserve (buffer_size
);
1826 intermediate_buffer
= buffer
.data ();
1828 /* Copy from the source to DEST_BUFFER. */
1829 switch (p
->location
)
1831 case DWARF_VALUE_REGISTER
:
1833 struct frame_info
*frame
= frame_find_by_id (c
->frame_id
);
1834 struct gdbarch
*arch
= get_frame_arch (frame
);
1835 int gdb_regnum
= dwarf_reg_to_regnum_or_error (arch
, p
->v
.regno
);
1837 LONGEST reg_offset
= source_offset
;
1839 if (gdbarch_byte_order (arch
) == BFD_ENDIAN_BIG
1840 && this_size
< register_size (arch
, gdb_regnum
))
1842 /* Big-endian, and we want less than full size. */
1843 reg_offset
= register_size (arch
, gdb_regnum
) - this_size
;
1844 /* We want the lower-order THIS_SIZE_BITS of the bytes
1845 we extract from the register. */
1846 source_offset_bits
+= 8 * this_size
- this_size_bits
;
1849 if (!get_frame_register_bytes (frame
, gdb_regnum
, reg_offset
,
1850 this_size
, buffer
.data (),
1853 /* Just so garbage doesn't ever shine through. */
1854 memset (buffer
.data (), 0, this_size
);
1857 mark_value_bits_optimized_out (v
, offset
, this_size_bits
);
1859 mark_value_bits_unavailable (v
, offset
, this_size_bits
);
1862 copy_bitwise (contents
, dest_offset_bits
,
1863 intermediate_buffer
, source_offset_bits
% 8,
1864 this_size_bits
, bits_big_endian
);
1868 case DWARF_VALUE_MEMORY
:
1869 read_value_memory (v
, offset
,
1870 p
->v
.mem
.in_stack_memory
,
1871 p
->v
.mem
.addr
+ source_offset
,
1872 buffer
.data (), this_size
);
1873 copy_bitwise (contents
, dest_offset_bits
,
1874 intermediate_buffer
, source_offset_bits
% 8,
1875 this_size_bits
, bits_big_endian
);
1878 case DWARF_VALUE_STACK
:
1880 struct objfile
*objfile
= dwarf2_per_cu_objfile (c
->per_cu
);
1881 struct gdbarch
*objfile_gdbarch
= get_objfile_arch (objfile
);
1882 ULONGEST stack_value_size_bits
1883 = 8 * TYPE_LENGTH (value_type (p
->v
.value
));
1885 /* Use zeroes if piece reaches beyond stack value. */
1886 if (p
->size
> stack_value_size_bits
)
1889 /* Piece is anchored at least significant bit end. */
1890 if (gdbarch_byte_order (objfile_gdbarch
) == BFD_ENDIAN_BIG
)
1891 source_offset_bits
+= stack_value_size_bits
- p
->size
;
1893 copy_bitwise (contents
, dest_offset_bits
,
1894 value_contents_all (p
->v
.value
),
1896 this_size_bits
, bits_big_endian
);
1900 case DWARF_VALUE_LITERAL
:
1902 size_t n
= this_size
;
1904 if (n
> p
->v
.literal
.length
- source_offset
)
1905 n
= (p
->v
.literal
.length
>= source_offset
1906 ? p
->v
.literal
.length
- source_offset
1909 intermediate_buffer
= p
->v
.literal
.data
+ source_offset
;
1911 copy_bitwise (contents
, dest_offset_bits
,
1912 intermediate_buffer
, source_offset_bits
% 8,
1913 this_size_bits
, bits_big_endian
);
1917 /* These bits show up as zeros -- but do not cause the value
1918 to be considered optimized-out. */
1919 case DWARF_VALUE_IMPLICIT_POINTER
:
1922 case DWARF_VALUE_OPTIMIZED_OUT
:
1923 mark_value_bits_optimized_out (v
, offset
, this_size_bits
);
1927 internal_error (__FILE__
, __LINE__
, _("invalid location type"));
1930 offset
+= this_size_bits
;
1935 write_pieced_value (struct value
*to
, struct value
*from
)
1939 ULONGEST bits_to_skip
;
1940 const gdb_byte
*contents
;
1941 struct piece_closure
*c
1942 = (struct piece_closure
*) value_computed_closure (to
);
1944 size_t buffer_size
= 0;
1945 std::vector
<gdb_byte
> buffer
;
1947 = gdbarch_bits_big_endian (get_type_arch (value_type (to
)));
1949 contents
= value_contents (from
);
1950 bits_to_skip
= 8 * value_offset (to
);
1951 if (value_bitsize (to
))
1953 bits_to_skip
+= value_bitpos (to
);
1954 type_len
= value_bitsize (to
);
1957 type_len
= 8 * TYPE_LENGTH (value_type (to
));
1959 for (i
= 0; i
< c
->n_pieces
&& offset
< type_len
; i
++)
1961 struct dwarf_expr_piece
*p
= &c
->pieces
[i
];
1962 size_t this_size_bits
, this_size
;
1963 long dest_offset_bits
, source_offset_bits
, dest_offset
, source_offset
;
1965 const gdb_byte
*source_buffer
;
1967 this_size_bits
= p
->size
;
1968 if (bits_to_skip
> 0 && bits_to_skip
>= this_size_bits
)
1970 bits_to_skip
-= this_size_bits
;
1973 if (bits_to_skip
> 0)
1975 dest_offset_bits
= bits_to_skip
;
1976 source_offset_bits
= 0;
1977 this_size_bits
-= bits_to_skip
;
1982 dest_offset_bits
= 0;
1983 source_offset_bits
= offset
;
1985 if (this_size_bits
> type_len
- offset
)
1986 this_size_bits
= type_len
- offset
;
1988 this_size
= (this_size_bits
+ source_offset_bits
% 8 + 7) / 8;
1989 source_offset
= source_offset_bits
/ 8;
1990 dest_offset
= dest_offset_bits
/ 8;
1991 if (dest_offset_bits
% 8 == 0 && source_offset_bits
% 8 == 0)
1993 source_buffer
= contents
+ source_offset
;
1998 if (buffer_size
< this_size
)
2000 buffer_size
= this_size
;
2001 buffer
.reserve (buffer_size
);
2003 source_buffer
= buffer
.data ();
2007 switch (p
->location
)
2009 case DWARF_VALUE_REGISTER
:
2011 struct frame_info
*frame
= frame_find_by_id (c
->frame_id
);
2012 struct gdbarch
*arch
= get_frame_arch (frame
);
2013 int gdb_regnum
= dwarf_reg_to_regnum_or_error (arch
, p
->v
.regno
);
2014 int reg_offset
= dest_offset
;
2016 if (gdbarch_byte_order (arch
) == BFD_ENDIAN_BIG
2017 && this_size
<= register_size (arch
, gdb_regnum
))
2019 /* Big-endian, and we want less than full size. */
2020 reg_offset
= register_size (arch
, gdb_regnum
) - this_size
;
2027 if (!get_frame_register_bytes (frame
, gdb_regnum
, reg_offset
,
2028 this_size
, buffer
.data (),
2032 throw_error (OPTIMIZED_OUT_ERROR
,
2033 _("Can't do read-modify-write to "
2034 "update bitfield; containing word "
2035 "has been optimized out"));
2037 throw_error (NOT_AVAILABLE_ERROR
,
2038 _("Can't do read-modify-write to update "
2039 "bitfield; containing word "
2042 copy_bitwise (buffer
.data (), dest_offset_bits
,
2043 contents
, source_offset_bits
,
2048 put_frame_register_bytes (frame
, gdb_regnum
, reg_offset
,
2049 this_size
, source_buffer
);
2052 case DWARF_VALUE_MEMORY
:
2055 /* Only the first and last bytes can possibly have any
2057 read_memory (p
->v
.mem
.addr
+ dest_offset
, buffer
.data (), 1);
2058 read_memory (p
->v
.mem
.addr
+ dest_offset
+ this_size
- 1,
2059 &buffer
[this_size
- 1], 1);
2060 copy_bitwise (buffer
.data (), dest_offset_bits
,
2061 contents
, source_offset_bits
,
2066 write_memory (p
->v
.mem
.addr
+ dest_offset
,
2067 source_buffer
, this_size
);
2070 mark_value_bytes_optimized_out (to
, 0, TYPE_LENGTH (value_type (to
)));
2073 offset
+= this_size_bits
;
2077 /* An implementation of an lval_funcs method to see whether a value is
2078 a synthetic pointer. */
2081 check_pieced_synthetic_pointer (const struct value
*value
, LONGEST bit_offset
,
2084 struct piece_closure
*c
2085 = (struct piece_closure
*) value_computed_closure (value
);
2088 bit_offset
+= 8 * value_offset (value
);
2089 if (value_bitsize (value
))
2090 bit_offset
+= value_bitpos (value
);
2092 for (i
= 0; i
< c
->n_pieces
&& bit_length
> 0; i
++)
2094 struct dwarf_expr_piece
*p
= &c
->pieces
[i
];
2095 size_t this_size_bits
= p
->size
;
2099 if (bit_offset
>= this_size_bits
)
2101 bit_offset
-= this_size_bits
;
2105 bit_length
-= this_size_bits
- bit_offset
;
2109 bit_length
-= this_size_bits
;
2111 if (p
->location
!= DWARF_VALUE_IMPLICIT_POINTER
)
2118 /* A wrapper function for get_frame_address_in_block. */
2121 get_frame_address_in_block_wrapper (void *baton
)
2123 return get_frame_address_in_block ((struct frame_info
*) baton
);
2126 /* Fetch a DW_AT_const_value through a synthetic pointer. */
2128 static struct value
*
2129 fetch_const_value_from_synthetic_pointer (sect_offset die
, LONGEST byte_offset
,
2130 struct dwarf2_per_cu_data
*per_cu
,
2133 struct value
*result
= NULL
;
2134 struct obstack temp_obstack
;
2135 struct cleanup
*cleanup
;
2136 const gdb_byte
*bytes
;
2139 obstack_init (&temp_obstack
);
2140 cleanup
= make_cleanup_obstack_free (&temp_obstack
);
2141 bytes
= dwarf2_fetch_constant_bytes (die
, per_cu
, &temp_obstack
, &len
);
2145 if (byte_offset
>= 0
2146 && byte_offset
+ TYPE_LENGTH (TYPE_TARGET_TYPE (type
)) <= len
)
2148 bytes
+= byte_offset
;
2149 result
= value_from_contents (TYPE_TARGET_TYPE (type
), bytes
);
2152 invalid_synthetic_pointer ();
2155 result
= allocate_optimized_out_value (TYPE_TARGET_TYPE (type
));
2157 do_cleanups (cleanup
);
2162 /* Fetch the value pointed to by a synthetic pointer. */
2164 static struct value
*
2165 indirect_synthetic_pointer (sect_offset die
, LONGEST byte_offset
,
2166 struct dwarf2_per_cu_data
*per_cu
,
2167 struct frame_info
*frame
, struct type
*type
)
2169 /* Fetch the location expression of the DIE we're pointing to. */
2170 struct dwarf2_locexpr_baton baton
2171 = dwarf2_fetch_die_loc_sect_off (die
, per_cu
,
2172 get_frame_address_in_block_wrapper
, frame
);
2174 /* Get type of pointed-to DIE. */
2175 struct type
*orig_type
= dwarf2_fetch_die_type_sect_off (die
, per_cu
);
2176 if (orig_type
== NULL
)
2177 invalid_synthetic_pointer ();
2179 /* If pointed-to DIE has a DW_AT_location, evaluate it and return the
2180 resulting value. Otherwise, it may have a DW_AT_const_value instead,
2181 or it may've been optimized out. */
2182 if (baton
.data
!= NULL
)
2183 return dwarf2_evaluate_loc_desc_full (orig_type
, frame
, baton
.data
,
2184 baton
.size
, baton
.per_cu
,
2185 TYPE_TARGET_TYPE (type
),
2188 return fetch_const_value_from_synthetic_pointer (die
, byte_offset
, per_cu
,
2192 /* An implementation of an lval_funcs method to indirect through a
2193 pointer. This handles the synthetic pointer case when needed. */
2195 static struct value
*
2196 indirect_pieced_value (struct value
*value
)
2198 struct piece_closure
*c
2199 = (struct piece_closure
*) value_computed_closure (value
);
2201 struct frame_info
*frame
;
2202 struct dwarf2_locexpr_baton baton
;
2205 struct dwarf_expr_piece
*piece
= NULL
;
2206 LONGEST byte_offset
;
2207 enum bfd_endian byte_order
;
2209 type
= check_typedef (value_type (value
));
2210 if (TYPE_CODE (type
) != TYPE_CODE_PTR
)
2213 bit_length
= 8 * TYPE_LENGTH (type
);
2214 bit_offset
= 8 * value_offset (value
);
2215 if (value_bitsize (value
))
2216 bit_offset
+= value_bitpos (value
);
2218 for (i
= 0; i
< c
->n_pieces
&& bit_length
> 0; i
++)
2220 struct dwarf_expr_piece
*p
= &c
->pieces
[i
];
2221 size_t this_size_bits
= p
->size
;
2225 if (bit_offset
>= this_size_bits
)
2227 bit_offset
-= this_size_bits
;
2231 bit_length
-= this_size_bits
- bit_offset
;
2235 bit_length
-= this_size_bits
;
2237 if (p
->location
!= DWARF_VALUE_IMPLICIT_POINTER
)
2240 if (bit_length
!= 0)
2241 error (_("Invalid use of DW_OP_implicit_pointer"));
2247 gdb_assert (piece
!= NULL
);
2248 frame
= get_selected_frame (_("No frame selected."));
2250 /* This is an offset requested by GDB, such as value subscripts.
2251 However, due to how synthetic pointers are implemented, this is
2252 always presented to us as a pointer type. This means we have to
2253 sign-extend it manually as appropriate. Use raw
2254 extract_signed_integer directly rather than value_as_address and
2255 sign extend afterwards on architectures that would need it
2256 (mostly everywhere except MIPS, which has signed addresses) as
2257 the later would go through gdbarch_pointer_to_address and thus
2258 return a CORE_ADDR with high bits set on architectures that
2259 encode address spaces and other things in CORE_ADDR. */
2260 byte_order
= gdbarch_byte_order (get_frame_arch (frame
));
2261 byte_offset
= extract_signed_integer (value_contents (value
),
2262 TYPE_LENGTH (type
), byte_order
);
2263 byte_offset
+= piece
->v
.ptr
.offset
;
2265 return indirect_synthetic_pointer (piece
->v
.ptr
.die_sect_off
,
2266 byte_offset
, c
->per_cu
,
2270 /* Implementation of the coerce_ref method of lval_funcs for synthetic C++
2273 static struct value
*
2274 coerce_pieced_ref (const struct value
*value
)
2276 struct type
*type
= check_typedef (value_type (value
));
2278 if (value_bits_synthetic_pointer (value
, value_embedded_offset (value
),
2279 TARGET_CHAR_BIT
* TYPE_LENGTH (type
)))
2281 const struct piece_closure
*closure
2282 = (struct piece_closure
*) value_computed_closure (value
);
2283 struct frame_info
*frame
2284 = get_selected_frame (_("No frame selected."));
2286 /* gdb represents synthetic pointers as pieced values with a single
2288 gdb_assert (closure
!= NULL
);
2289 gdb_assert (closure
->n_pieces
== 1);
2291 return indirect_synthetic_pointer (closure
->pieces
->v
.ptr
.die_sect_off
,
2292 closure
->pieces
->v
.ptr
.offset
,
2293 closure
->per_cu
, frame
, type
);
2297 /* Else: not a synthetic reference; do nothing. */
2303 copy_pieced_value_closure (const struct value
*v
)
2305 struct piece_closure
*c
2306 = (struct piece_closure
*) value_computed_closure (v
);
2313 free_pieced_value_closure (struct value
*v
)
2315 struct piece_closure
*c
2316 = (struct piece_closure
*) value_computed_closure (v
);
2323 for (i
= 0; i
< c
->n_pieces
; ++i
)
2324 if (c
->pieces
[i
].location
== DWARF_VALUE_STACK
)
2325 value_free (c
->pieces
[i
].v
.value
);
2332 /* Functions for accessing a variable described by DW_OP_piece. */
2333 static const struct lval_funcs pieced_value_funcs
= {
2336 indirect_pieced_value
,
2338 check_pieced_synthetic_pointer
,
2339 copy_pieced_value_closure
,
2340 free_pieced_value_closure
2343 /* Evaluate a location description, starting at DATA and with length
2344 SIZE, to find the current location of variable of TYPE in the
2345 context of FRAME. If SUBOBJ_TYPE is non-NULL, return instead the
2346 location of the subobject of type SUBOBJ_TYPE at byte offset
2347 SUBOBJ_BYTE_OFFSET within the variable of type TYPE. */
2349 static struct value
*
2350 dwarf2_evaluate_loc_desc_full (struct type
*type
, struct frame_info
*frame
,
2351 const gdb_byte
*data
, size_t size
,
2352 struct dwarf2_per_cu_data
*per_cu
,
2353 struct type
*subobj_type
,
2354 LONGEST subobj_byte_offset
)
2356 struct value
*retval
;
2357 struct objfile
*objfile
= dwarf2_per_cu_objfile (per_cu
);
2359 if (subobj_type
== NULL
)
2362 subobj_byte_offset
= 0;
2364 else if (subobj_byte_offset
< 0)
2365 invalid_synthetic_pointer ();
2368 return allocate_optimized_out_value (subobj_type
);
2370 dwarf_evaluate_loc_desc ctx
;
2372 ctx
.per_cu
= per_cu
;
2373 ctx
.obj_address
= 0;
2375 scoped_value_mark free_values
;
2377 ctx
.gdbarch
= get_objfile_arch (objfile
);
2378 ctx
.addr_size
= dwarf2_per_cu_addr_size (per_cu
);
2379 ctx
.ref_addr_size
= dwarf2_per_cu_ref_addr_size (per_cu
);
2380 ctx
.offset
= dwarf2_per_cu_text_offset (per_cu
);
2384 ctx
.eval (data
, size
);
2386 CATCH (ex
, RETURN_MASK_ERROR
)
2388 if (ex
.error
== NOT_AVAILABLE_ERROR
)
2390 free_values
.free_to_mark ();
2391 retval
= allocate_value (subobj_type
);
2392 mark_value_bytes_unavailable (retval
, 0,
2393 TYPE_LENGTH (subobj_type
));
2396 else if (ex
.error
== NO_ENTRY_VALUE_ERROR
)
2398 if (entry_values_debug
)
2399 exception_print (gdb_stdout
, ex
);
2400 free_values
.free_to_mark ();
2401 return allocate_optimized_out_value (subobj_type
);
2404 throw_exception (ex
);
2408 if (ctx
.num_pieces
> 0)
2410 struct piece_closure
*c
;
2411 ULONGEST bit_size
= 0;
2414 for (i
= 0; i
< ctx
.num_pieces
; ++i
)
2415 bit_size
+= ctx
.pieces
[i
].size
;
2416 if (8 * (subobj_byte_offset
+ TYPE_LENGTH (subobj_type
)) > bit_size
)
2417 invalid_synthetic_pointer ();
2419 c
= allocate_piece_closure (per_cu
, ctx
.num_pieces
, ctx
.pieces
,
2420 ctx
.addr_size
, frame
);
2421 /* We must clean up the value chain after creating the piece
2422 closure but before allocating the result. */
2423 free_values
.free_to_mark ();
2424 retval
= allocate_computed_value (subobj_type
,
2425 &pieced_value_funcs
, c
);
2426 set_value_offset (retval
, subobj_byte_offset
);
2430 switch (ctx
.location
)
2432 case DWARF_VALUE_REGISTER
:
2434 struct gdbarch
*arch
= get_frame_arch (frame
);
2436 = longest_to_int (value_as_long (ctx
.fetch (0)));
2437 int gdb_regnum
= dwarf_reg_to_regnum_or_error (arch
, dwarf_regnum
);
2439 if (subobj_byte_offset
!= 0)
2440 error (_("cannot use offset on synthetic pointer to register"));
2441 free_values
.free_to_mark ();
2442 retval
= value_from_register (subobj_type
, gdb_regnum
, frame
);
2443 if (value_optimized_out (retval
))
2447 /* This means the register has undefined value / was
2448 not saved. As we're computing the location of some
2449 variable etc. in the program, not a value for
2450 inspecting a register ($pc, $sp, etc.), return a
2451 generic optimized out value instead, so that we show
2452 <optimized out> instead of <not saved>. */
2453 tmp
= allocate_value (subobj_type
);
2454 value_contents_copy (tmp
, 0, retval
, 0,
2455 TYPE_LENGTH (subobj_type
));
2461 case DWARF_VALUE_MEMORY
:
2463 struct type
*ptr_type
;
2464 CORE_ADDR address
= ctx
.fetch_address (0);
2465 int in_stack_memory
= ctx
.fetch_in_stack_memory (0);
2467 /* DW_OP_deref_size (and possibly other operations too) may
2468 create a pointer instead of an address. Ideally, the
2469 pointer to address conversion would be performed as part
2470 of those operations, but the type of the object to
2471 which the address refers is not known at the time of
2472 the operation. Therefore, we do the conversion here
2473 since the type is readily available. */
2475 switch (TYPE_CODE (subobj_type
))
2477 case TYPE_CODE_FUNC
:
2478 case TYPE_CODE_METHOD
:
2479 ptr_type
= builtin_type (ctx
.gdbarch
)->builtin_func_ptr
;
2482 ptr_type
= builtin_type (ctx
.gdbarch
)->builtin_data_ptr
;
2485 address
= value_as_address (value_from_pointer (ptr_type
, address
));
2487 free_values
.free_to_mark ();
2488 retval
= value_at_lazy (subobj_type
,
2489 address
+ subobj_byte_offset
);
2490 if (in_stack_memory
)
2491 set_value_stack (retval
, 1);
2495 case DWARF_VALUE_STACK
:
2497 struct value
*value
= ctx
.fetch (0);
2498 size_t n
= TYPE_LENGTH (value_type (value
));
2499 size_t len
= TYPE_LENGTH (subobj_type
);
2500 size_t max
= TYPE_LENGTH (type
);
2501 struct gdbarch
*objfile_gdbarch
= get_objfile_arch (objfile
);
2502 struct cleanup
*cleanup
;
2504 if (subobj_byte_offset
+ len
> max
)
2505 invalid_synthetic_pointer ();
2507 /* Preserve VALUE because we are going to free values back
2508 to the mark, but we still need the value contents
2510 value_incref (value
);
2511 free_values
.free_to_mark ();
2512 cleanup
= make_cleanup_value_free (value
);
2514 retval
= allocate_value (subobj_type
);
2516 /* The given offset is relative to the actual object. */
2517 if (gdbarch_byte_order (objfile_gdbarch
) == BFD_ENDIAN_BIG
)
2518 subobj_byte_offset
+= n
- max
;
2520 memcpy (value_contents_raw (retval
),
2521 value_contents_all (value
) + subobj_byte_offset
, len
);
2523 do_cleanups (cleanup
);
2527 case DWARF_VALUE_LITERAL
:
2530 size_t n
= TYPE_LENGTH (subobj_type
);
2532 if (subobj_byte_offset
+ n
> ctx
.len
)
2533 invalid_synthetic_pointer ();
2535 free_values
.free_to_mark ();
2536 retval
= allocate_value (subobj_type
);
2537 contents
= value_contents_raw (retval
);
2538 memcpy (contents
, ctx
.data
+ subobj_byte_offset
, n
);
2542 case DWARF_VALUE_OPTIMIZED_OUT
:
2543 free_values
.free_to_mark ();
2544 retval
= allocate_optimized_out_value (subobj_type
);
2547 /* DWARF_VALUE_IMPLICIT_POINTER was converted to a pieced
2548 operation by execute_stack_op. */
2549 case DWARF_VALUE_IMPLICIT_POINTER
:
2550 /* DWARF_VALUE_OPTIMIZED_OUT can't occur in this context --
2551 it can only be encountered when making a piece. */
2553 internal_error (__FILE__
, __LINE__
, _("invalid location type"));
2557 set_value_initialized (retval
, ctx
.initialized
);
2562 /* The exported interface to dwarf2_evaluate_loc_desc_full; it always
2563 passes 0 as the byte_offset. */
2566 dwarf2_evaluate_loc_desc (struct type
*type
, struct frame_info
*frame
,
2567 const gdb_byte
*data
, size_t size
,
2568 struct dwarf2_per_cu_data
*per_cu
)
2570 return dwarf2_evaluate_loc_desc_full (type
, frame
, data
, size
, per_cu
,
2574 /* Evaluates a dwarf expression and stores the result in VAL, expecting
2575 that the dwarf expression only produces a single CORE_ADDR. FRAME is the
2576 frame in which the expression is evaluated. ADDR is a context (location of
2577 a variable) and might be needed to evaluate the location expression.
2578 Returns 1 on success, 0 otherwise. */
2581 dwarf2_locexpr_baton_eval (const struct dwarf2_locexpr_baton
*dlbaton
,
2582 struct frame_info
*frame
,
2586 struct objfile
*objfile
;
2588 if (dlbaton
== NULL
|| dlbaton
->size
== 0)
2591 dwarf_evaluate_loc_desc ctx
;
2594 ctx
.per_cu
= dlbaton
->per_cu
;
2595 ctx
.obj_address
= addr
;
2597 objfile
= dwarf2_per_cu_objfile (dlbaton
->per_cu
);
2599 ctx
.gdbarch
= get_objfile_arch (objfile
);
2600 ctx
.addr_size
= dwarf2_per_cu_addr_size (dlbaton
->per_cu
);
2601 ctx
.ref_addr_size
= dwarf2_per_cu_ref_addr_size (dlbaton
->per_cu
);
2602 ctx
.offset
= dwarf2_per_cu_text_offset (dlbaton
->per_cu
);
2604 ctx
.eval (dlbaton
->data
, dlbaton
->size
);
2606 switch (ctx
.location
)
2608 case DWARF_VALUE_REGISTER
:
2609 case DWARF_VALUE_MEMORY
:
2610 case DWARF_VALUE_STACK
:
2611 *valp
= ctx
.fetch_address (0);
2612 if (ctx
.location
== DWARF_VALUE_REGISTER
)
2613 *valp
= ctx
.read_addr_from_reg (*valp
);
2615 case DWARF_VALUE_LITERAL
:
2616 *valp
= extract_signed_integer (ctx
.data
, ctx
.len
,
2617 gdbarch_byte_order (ctx
.gdbarch
));
2619 /* Unsupported dwarf values. */
2620 case DWARF_VALUE_OPTIMIZED_OUT
:
2621 case DWARF_VALUE_IMPLICIT_POINTER
:
2628 /* See dwarf2loc.h. */
2631 dwarf2_evaluate_property (const struct dynamic_prop
*prop
,
2632 struct frame_info
*frame
,
2633 struct property_addr_info
*addr_stack
,
2639 if (frame
== NULL
&& has_stack_frames ())
2640 frame
= get_selected_frame (NULL
);
2646 const struct dwarf2_property_baton
*baton
2647 = (const struct dwarf2_property_baton
*) prop
->data
.baton
;
2649 if (dwarf2_locexpr_baton_eval (&baton
->locexpr
, frame
,
2650 addr_stack
? addr_stack
->addr
: 0,
2653 if (baton
->referenced_type
)
2655 struct value
*val
= value_at (baton
->referenced_type
, *value
);
2657 *value
= value_as_address (val
);
2666 struct dwarf2_property_baton
*baton
2667 = (struct dwarf2_property_baton
*) prop
->data
.baton
;
2668 CORE_ADDR pc
= get_frame_address_in_block (frame
);
2669 const gdb_byte
*data
;
2673 data
= dwarf2_find_location_expression (&baton
->loclist
, &size
, pc
);
2676 val
= dwarf2_evaluate_loc_desc (baton
->referenced_type
, frame
, data
,
2677 size
, baton
->loclist
.per_cu
);
2678 if (!value_optimized_out (val
))
2680 *value
= value_as_address (val
);
2688 *value
= prop
->data
.const_val
;
2691 case PROP_ADDR_OFFSET
:
2693 struct dwarf2_property_baton
*baton
2694 = (struct dwarf2_property_baton
*) prop
->data
.baton
;
2695 struct property_addr_info
*pinfo
;
2698 for (pinfo
= addr_stack
; pinfo
!= NULL
; pinfo
= pinfo
->next
)
2699 if (pinfo
->type
== baton
->referenced_type
)
2702 error (_("cannot find reference address for offset property"));
2703 if (pinfo
->valaddr
!= NULL
)
2704 val
= value_from_contents
2705 (baton
->offset_info
.type
,
2706 pinfo
->valaddr
+ baton
->offset_info
.offset
);
2708 val
= value_at (baton
->offset_info
.type
,
2709 pinfo
->addr
+ baton
->offset_info
.offset
);
2710 *value
= value_as_address (val
);
2718 /* See dwarf2loc.h. */
2721 dwarf2_compile_property_to_c (string_file
&stream
,
2722 const char *result_name
,
2723 struct gdbarch
*gdbarch
,
2724 unsigned char *registers_used
,
2725 const struct dynamic_prop
*prop
,
2729 struct dwarf2_property_baton
*baton
2730 = (struct dwarf2_property_baton
*) prop
->data
.baton
;
2731 const gdb_byte
*data
;
2733 struct dwarf2_per_cu_data
*per_cu
;
2735 if (prop
->kind
== PROP_LOCEXPR
)
2737 data
= baton
->locexpr
.data
;
2738 size
= baton
->locexpr
.size
;
2739 per_cu
= baton
->locexpr
.per_cu
;
2743 gdb_assert (prop
->kind
== PROP_LOCLIST
);
2745 data
= dwarf2_find_location_expression (&baton
->loclist
, &size
, pc
);
2746 per_cu
= baton
->loclist
.per_cu
;
2749 compile_dwarf_bounds_to_c (stream
, result_name
, prop
, sym
, pc
,
2750 gdbarch
, registers_used
,
2751 dwarf2_per_cu_addr_size (per_cu
),
2752 data
, data
+ size
, per_cu
);
2756 /* Helper functions and baton for dwarf2_loc_desc_get_symbol_read_needs. */
2758 class symbol_needs_eval_context
: public dwarf_expr_context
2762 enum symbol_needs_kind needs
;
2763 struct dwarf2_per_cu_data
*per_cu
;
2765 /* Reads from registers do require a frame. */
2766 CORE_ADDR
read_addr_from_reg (int regnum
) OVERRIDE
2768 needs
= SYMBOL_NEEDS_FRAME
;
2772 /* "get_reg_value" callback: Reads from registers do require a
2775 struct value
*get_reg_value (struct type
*type
, int regnum
) OVERRIDE
2777 needs
= SYMBOL_NEEDS_FRAME
;
2778 return value_zero (type
, not_lval
);
2781 /* Reads from memory do not require a frame. */
2782 void read_mem (gdb_byte
*buf
, CORE_ADDR addr
, size_t len
) OVERRIDE
2784 memset (buf
, 0, len
);
2787 /* Frame-relative accesses do require a frame. */
2788 void get_frame_base (const gdb_byte
**start
, size_t *length
) OVERRIDE
2790 static gdb_byte lit0
= DW_OP_lit0
;
2795 needs
= SYMBOL_NEEDS_FRAME
;
2798 /* CFA accesses require a frame. */
2799 CORE_ADDR
get_frame_cfa () OVERRIDE
2801 needs
= SYMBOL_NEEDS_FRAME
;
2805 CORE_ADDR
get_frame_pc () OVERRIDE
2807 needs
= SYMBOL_NEEDS_FRAME
;
2811 /* Thread-local accesses require registers, but not a frame. */
2812 CORE_ADDR
get_tls_address (CORE_ADDR offset
) OVERRIDE
2814 if (needs
<= SYMBOL_NEEDS_REGISTERS
)
2815 needs
= SYMBOL_NEEDS_REGISTERS
;
2819 /* Helper interface of per_cu_dwarf_call for
2820 dwarf2_loc_desc_get_symbol_read_needs. */
2822 void dwarf_call (cu_offset die_offset
) OVERRIDE
2824 per_cu_dwarf_call (this, die_offset
, per_cu
);
2827 /* DW_OP_entry_value accesses require a caller, therefore a
2830 void push_dwarf_reg_entry_value (enum call_site_parameter_kind kind
,
2831 union call_site_parameter_u kind_u
,
2832 int deref_size
) OVERRIDE
2834 needs
= SYMBOL_NEEDS_FRAME
;
2836 /* The expression may require some stub values on DWARF stack. */
2837 push_address (0, 0);
2840 /* DW_OP_GNU_addr_index doesn't require a frame. */
2842 CORE_ADDR
get_addr_index (unsigned int index
) OVERRIDE
2844 /* Nothing to do. */
2848 /* DW_OP_push_object_address has a frame already passed through. */
2850 CORE_ADDR
get_object_address () OVERRIDE
2852 /* Nothing to do. */
2857 /* Compute the correct symbol_needs_kind value for the location
2858 expression at DATA (length SIZE). */
2860 static enum symbol_needs_kind
2861 dwarf2_loc_desc_get_symbol_read_needs (const gdb_byte
*data
, size_t size
,
2862 struct dwarf2_per_cu_data
*per_cu
)
2865 struct objfile
*objfile
= dwarf2_per_cu_objfile (per_cu
);
2867 scoped_value_mark free_values
;
2869 symbol_needs_eval_context ctx
;
2871 ctx
.needs
= SYMBOL_NEEDS_NONE
;
2872 ctx
.per_cu
= per_cu
;
2873 ctx
.gdbarch
= get_objfile_arch (objfile
);
2874 ctx
.addr_size
= dwarf2_per_cu_addr_size (per_cu
);
2875 ctx
.ref_addr_size
= dwarf2_per_cu_ref_addr_size (per_cu
);
2876 ctx
.offset
= dwarf2_per_cu_text_offset (per_cu
);
2878 ctx
.eval (data
, size
);
2880 in_reg
= ctx
.location
== DWARF_VALUE_REGISTER
;
2882 if (ctx
.num_pieces
> 0)
2886 /* If the location has several pieces, and any of them are in
2887 registers, then we will need a frame to fetch them from. */
2888 for (i
= 0; i
< ctx
.num_pieces
; i
++)
2889 if (ctx
.pieces
[i
].location
== DWARF_VALUE_REGISTER
)
2894 ctx
.needs
= SYMBOL_NEEDS_FRAME
;
2898 /* A helper function that throws an unimplemented error mentioning a
2899 given DWARF operator. */
2902 unimplemented (unsigned int op
)
2904 const char *name
= get_DW_OP_name (op
);
2907 error (_("DWARF operator %s cannot be translated to an agent expression"),
2910 error (_("Unknown DWARF operator 0x%02x cannot be translated "
2911 "to an agent expression"),
2917 This is basically a wrapper on gdbarch_dwarf2_reg_to_regnum so that we
2918 can issue a complaint, which is better than having every target's
2919 implementation of dwarf2_reg_to_regnum do it. */
2922 dwarf_reg_to_regnum (struct gdbarch
*arch
, int dwarf_reg
)
2924 int reg
= gdbarch_dwarf2_reg_to_regnum (arch
, dwarf_reg
);
2928 complaint (&symfile_complaints
,
2929 _("bad DWARF register number %d"), dwarf_reg
);
2934 /* Subroutine of dwarf_reg_to_regnum_or_error to simplify it.
2935 Throw an error because DWARF_REG is bad. */
2938 throw_bad_regnum_error (ULONGEST dwarf_reg
)
2940 /* Still want to print -1 as "-1".
2941 We *could* have int and ULONGEST versions of dwarf2_reg_to_regnum_or_error
2942 but that's overkill for now. */
2943 if ((int) dwarf_reg
== dwarf_reg
)
2944 error (_("Unable to access DWARF register number %d"), (int) dwarf_reg
);
2945 error (_("Unable to access DWARF register number %s"),
2946 pulongest (dwarf_reg
));
2949 /* See dwarf2loc.h. */
2952 dwarf_reg_to_regnum_or_error (struct gdbarch
*arch
, ULONGEST dwarf_reg
)
2956 if (dwarf_reg
> INT_MAX
)
2957 throw_bad_regnum_error (dwarf_reg
);
2958 /* Yes, we will end up issuing a complaint and an error if DWARF_REG is
2959 bad, but that's ok. */
2960 reg
= dwarf_reg_to_regnum (arch
, (int) dwarf_reg
);
2962 throw_bad_regnum_error (dwarf_reg
);
2966 /* A helper function that emits an access to memory. ARCH is the
2967 target architecture. EXPR is the expression which we are building.
2968 NBITS is the number of bits we want to read. This emits the
2969 opcodes needed to read the memory and then extract the desired
2973 access_memory (struct gdbarch
*arch
, struct agent_expr
*expr
, ULONGEST nbits
)
2975 ULONGEST nbytes
= (nbits
+ 7) / 8;
2977 gdb_assert (nbytes
> 0 && nbytes
<= sizeof (LONGEST
));
2980 ax_trace_quick (expr
, nbytes
);
2983 ax_simple (expr
, aop_ref8
);
2984 else if (nbits
<= 16)
2985 ax_simple (expr
, aop_ref16
);
2986 else if (nbits
<= 32)
2987 ax_simple (expr
, aop_ref32
);
2989 ax_simple (expr
, aop_ref64
);
2991 /* If we read exactly the number of bytes we wanted, we're done. */
2992 if (8 * nbytes
== nbits
)
2995 if (gdbarch_bits_big_endian (arch
))
2997 /* On a bits-big-endian machine, we want the high-order
2999 ax_const_l (expr
, 8 * nbytes
- nbits
);
3000 ax_simple (expr
, aop_rsh_unsigned
);
3004 /* On a bits-little-endian box, we want the low-order NBITS. */
3005 ax_zero_ext (expr
, nbits
);
3009 /* A helper function to return the frame's PC. */
3012 get_ax_pc (void *baton
)
3014 struct agent_expr
*expr
= (struct agent_expr
*) baton
;
3019 /* Compile a DWARF location expression to an agent expression.
3021 EXPR is the agent expression we are building.
3022 LOC is the agent value we modify.
3023 ARCH is the architecture.
3024 ADDR_SIZE is the size of addresses, in bytes.
3025 OP_PTR is the start of the location expression.
3026 OP_END is one past the last byte of the location expression.
3028 This will throw an exception for various kinds of errors -- for
3029 example, if the expression cannot be compiled, or if the expression
3033 dwarf2_compile_expr_to_ax (struct agent_expr
*expr
, struct axs_value
*loc
,
3034 struct gdbarch
*arch
, unsigned int addr_size
,
3035 const gdb_byte
*op_ptr
, const gdb_byte
*op_end
,
3036 struct dwarf2_per_cu_data
*per_cu
)
3039 std::vector
<int> dw_labels
, patches
;
3040 const gdb_byte
* const base
= op_ptr
;
3041 const gdb_byte
*previous_piece
= op_ptr
;
3042 enum bfd_endian byte_order
= gdbarch_byte_order (arch
);
3043 ULONGEST bits_collected
= 0;
3044 unsigned int addr_size_bits
= 8 * addr_size
;
3045 int bits_big_endian
= gdbarch_bits_big_endian (arch
);
3047 std::vector
<int> offsets (op_end
- op_ptr
, -1);
3049 /* By default we are making an address. */
3050 loc
->kind
= axs_lvalue_memory
;
3052 while (op_ptr
< op_end
)
3054 enum dwarf_location_atom op
= (enum dwarf_location_atom
) *op_ptr
;
3055 uint64_t uoffset
, reg
;
3059 offsets
[op_ptr
- base
] = expr
->len
;
3062 /* Our basic approach to code generation is to map DWARF
3063 operations directly to AX operations. However, there are
3066 First, DWARF works on address-sized units, but AX always uses
3067 LONGEST. For most operations we simply ignore this
3068 difference; instead we generate sign extensions as needed
3069 before division and comparison operations. It would be nice
3070 to omit the sign extensions, but there is no way to determine
3071 the size of the target's LONGEST. (This code uses the size
3072 of the host LONGEST in some cases -- that is a bug but it is
3075 Second, some DWARF operations cannot be translated to AX.
3076 For these we simply fail. See
3077 http://sourceware.org/bugzilla/show_bug.cgi?id=11662. */
3112 ax_const_l (expr
, op
- DW_OP_lit0
);
3116 uoffset
= extract_unsigned_integer (op_ptr
, addr_size
, byte_order
);
3117 op_ptr
+= addr_size
;
3118 /* Some versions of GCC emit DW_OP_addr before
3119 DW_OP_GNU_push_tls_address. In this case the value is an
3120 index, not an address. We don't support things like
3121 branching between the address and the TLS op. */
3122 if (op_ptr
>= op_end
|| *op_ptr
!= DW_OP_GNU_push_tls_address
)
3123 uoffset
+= dwarf2_per_cu_text_offset (per_cu
);
3124 ax_const_l (expr
, uoffset
);
3128 ax_const_l (expr
, extract_unsigned_integer (op_ptr
, 1, byte_order
));
3132 ax_const_l (expr
, extract_signed_integer (op_ptr
, 1, byte_order
));
3136 ax_const_l (expr
, extract_unsigned_integer (op_ptr
, 2, byte_order
));
3140 ax_const_l (expr
, extract_signed_integer (op_ptr
, 2, byte_order
));
3144 ax_const_l (expr
, extract_unsigned_integer (op_ptr
, 4, byte_order
));
3148 ax_const_l (expr
, extract_signed_integer (op_ptr
, 4, byte_order
));
3152 ax_const_l (expr
, extract_unsigned_integer (op_ptr
, 8, byte_order
));
3156 ax_const_l (expr
, extract_signed_integer (op_ptr
, 8, byte_order
));
3160 op_ptr
= safe_read_uleb128 (op_ptr
, op_end
, &uoffset
);
3161 ax_const_l (expr
, uoffset
);
3164 op_ptr
= safe_read_sleb128 (op_ptr
, op_end
, &offset
);
3165 ax_const_l (expr
, offset
);
3200 dwarf_expr_require_composition (op_ptr
, op_end
, "DW_OP_regx");
3201 loc
->u
.reg
= dwarf_reg_to_regnum_or_error (arch
, op
- DW_OP_reg0
);
3202 loc
->kind
= axs_lvalue_register
;
3206 op_ptr
= safe_read_uleb128 (op_ptr
, op_end
, ®
);
3207 dwarf_expr_require_composition (op_ptr
, op_end
, "DW_OP_regx");
3208 loc
->u
.reg
= dwarf_reg_to_regnum_or_error (arch
, reg
);
3209 loc
->kind
= axs_lvalue_register
;
3212 case DW_OP_implicit_value
:
3216 op_ptr
= safe_read_uleb128 (op_ptr
, op_end
, &len
);
3217 if (op_ptr
+ len
> op_end
)
3218 error (_("DW_OP_implicit_value: too few bytes available."));
3219 if (len
> sizeof (ULONGEST
))
3220 error (_("Cannot translate DW_OP_implicit_value of %d bytes"),
3223 ax_const_l (expr
, extract_unsigned_integer (op_ptr
, len
,
3226 dwarf_expr_require_composition (op_ptr
, op_end
,
3227 "DW_OP_implicit_value");
3229 loc
->kind
= axs_rvalue
;
3233 case DW_OP_stack_value
:
3234 dwarf_expr_require_composition (op_ptr
, op_end
, "DW_OP_stack_value");
3235 loc
->kind
= axs_rvalue
;
3270 op_ptr
= safe_read_sleb128 (op_ptr
, op_end
, &offset
);
3271 i
= dwarf_reg_to_regnum_or_error (arch
, op
- DW_OP_breg0
);
3275 ax_const_l (expr
, offset
);
3276 ax_simple (expr
, aop_add
);
3281 op_ptr
= safe_read_uleb128 (op_ptr
, op_end
, ®
);
3282 op_ptr
= safe_read_sleb128 (op_ptr
, op_end
, &offset
);
3283 i
= dwarf_reg_to_regnum_or_error (arch
, reg
);
3287 ax_const_l (expr
, offset
);
3288 ax_simple (expr
, aop_add
);
3294 const gdb_byte
*datastart
;
3296 const struct block
*b
;
3297 struct symbol
*framefunc
;
3299 b
= block_for_pc (expr
->scope
);
3302 error (_("No block found for address"));
3304 framefunc
= block_linkage_function (b
);
3307 error (_("No function found for block"));
3309 func_get_frame_base_dwarf_block (framefunc
, expr
->scope
,
3310 &datastart
, &datalen
);
3312 op_ptr
= safe_read_sleb128 (op_ptr
, op_end
, &offset
);
3313 dwarf2_compile_expr_to_ax (expr
, loc
, arch
, addr_size
, datastart
,
3314 datastart
+ datalen
, per_cu
);
3315 if (loc
->kind
== axs_lvalue_register
)
3316 require_rvalue (expr
, loc
);
3320 ax_const_l (expr
, offset
);
3321 ax_simple (expr
, aop_add
);
3324 loc
->kind
= axs_lvalue_memory
;
3329 ax_simple (expr
, aop_dup
);
3333 ax_simple (expr
, aop_pop
);
3338 ax_pick (expr
, offset
);
3342 ax_simple (expr
, aop_swap
);
3350 ax_simple (expr
, aop_rot
);
3354 case DW_OP_deref_size
:
3358 if (op
== DW_OP_deref_size
)
3363 if (size
!= 1 && size
!= 2 && size
!= 4 && size
!= 8)
3364 error (_("Unsupported size %d in %s"),
3365 size
, get_DW_OP_name (op
));
3366 access_memory (arch
, expr
, size
* TARGET_CHAR_BIT
);
3371 /* Sign extend the operand. */
3372 ax_ext (expr
, addr_size_bits
);
3373 ax_simple (expr
, aop_dup
);
3374 ax_const_l (expr
, 0);
3375 ax_simple (expr
, aop_less_signed
);
3376 ax_simple (expr
, aop_log_not
);
3377 i
= ax_goto (expr
, aop_if_goto
);
3378 /* We have to emit 0 - X. */
3379 ax_const_l (expr
, 0);
3380 ax_simple (expr
, aop_swap
);
3381 ax_simple (expr
, aop_sub
);
3382 ax_label (expr
, i
, expr
->len
);
3386 /* No need to sign extend here. */
3387 ax_const_l (expr
, 0);
3388 ax_simple (expr
, aop_swap
);
3389 ax_simple (expr
, aop_sub
);
3393 /* Sign extend the operand. */
3394 ax_ext (expr
, addr_size_bits
);
3395 ax_simple (expr
, aop_bit_not
);
3398 case DW_OP_plus_uconst
:
3399 op_ptr
= safe_read_uleb128 (op_ptr
, op_end
, ®
);
3400 /* It would be really weird to emit `DW_OP_plus_uconst 0',
3401 but we micro-optimize anyhow. */
3404 ax_const_l (expr
, reg
);
3405 ax_simple (expr
, aop_add
);
3410 ax_simple (expr
, aop_bit_and
);
3414 /* Sign extend the operands. */
3415 ax_ext (expr
, addr_size_bits
);
3416 ax_simple (expr
, aop_swap
);
3417 ax_ext (expr
, addr_size_bits
);
3418 ax_simple (expr
, aop_swap
);
3419 ax_simple (expr
, aop_div_signed
);
3423 ax_simple (expr
, aop_sub
);
3427 ax_simple (expr
, aop_rem_unsigned
);
3431 ax_simple (expr
, aop_mul
);
3435 ax_simple (expr
, aop_bit_or
);
3439 ax_simple (expr
, aop_add
);
3443 ax_simple (expr
, aop_lsh
);
3447 ax_simple (expr
, aop_rsh_unsigned
);
3451 ax_simple (expr
, aop_rsh_signed
);
3455 ax_simple (expr
, aop_bit_xor
);
3459 /* Sign extend the operands. */
3460 ax_ext (expr
, addr_size_bits
);
3461 ax_simple (expr
, aop_swap
);
3462 ax_ext (expr
, addr_size_bits
);
3463 /* Note no swap here: A <= B is !(B < A). */
3464 ax_simple (expr
, aop_less_signed
);
3465 ax_simple (expr
, aop_log_not
);
3469 /* Sign extend the operands. */
3470 ax_ext (expr
, addr_size_bits
);
3471 ax_simple (expr
, aop_swap
);
3472 ax_ext (expr
, addr_size_bits
);
3473 ax_simple (expr
, aop_swap
);
3474 /* A >= B is !(A < B). */
3475 ax_simple (expr
, aop_less_signed
);
3476 ax_simple (expr
, aop_log_not
);
3480 /* Sign extend the operands. */
3481 ax_ext (expr
, addr_size_bits
);
3482 ax_simple (expr
, aop_swap
);
3483 ax_ext (expr
, addr_size_bits
);
3484 /* No need for a second swap here. */
3485 ax_simple (expr
, aop_equal
);
3489 /* Sign extend the operands. */
3490 ax_ext (expr
, addr_size_bits
);
3491 ax_simple (expr
, aop_swap
);
3492 ax_ext (expr
, addr_size_bits
);
3493 ax_simple (expr
, aop_swap
);
3494 ax_simple (expr
, aop_less_signed
);
3498 /* Sign extend the operands. */
3499 ax_ext (expr
, addr_size_bits
);
3500 ax_simple (expr
, aop_swap
);
3501 ax_ext (expr
, addr_size_bits
);
3502 /* Note no swap here: A > B is B < A. */
3503 ax_simple (expr
, aop_less_signed
);
3507 /* Sign extend the operands. */
3508 ax_ext (expr
, addr_size_bits
);
3509 ax_simple (expr
, aop_swap
);
3510 ax_ext (expr
, addr_size_bits
);
3511 /* No need for a swap here. */
3512 ax_simple (expr
, aop_equal
);
3513 ax_simple (expr
, aop_log_not
);
3516 case DW_OP_call_frame_cfa
:
3519 CORE_ADDR text_offset
;
3521 const gdb_byte
*cfa_start
, *cfa_end
;
3523 if (dwarf2_fetch_cfa_info (arch
, expr
->scope
, per_cu
,
3525 &text_offset
, &cfa_start
, &cfa_end
))
3528 ax_reg (expr
, regnum
);
3531 ax_const_l (expr
, off
);
3532 ax_simple (expr
, aop_add
);
3537 /* Another expression. */
3538 ax_const_l (expr
, text_offset
);
3539 dwarf2_compile_expr_to_ax (expr
, loc
, arch
, addr_size
,
3540 cfa_start
, cfa_end
, per_cu
);
3543 loc
->kind
= axs_lvalue_memory
;
3547 case DW_OP_GNU_push_tls_address
:
3548 case DW_OP_form_tls_address
:
3552 case DW_OP_push_object_address
:
3557 offset
= extract_signed_integer (op_ptr
, 2, byte_order
);
3559 i
= ax_goto (expr
, aop_goto
);
3560 dw_labels
.push_back (op_ptr
+ offset
- base
);
3561 patches
.push_back (i
);
3565 offset
= extract_signed_integer (op_ptr
, 2, byte_order
);
3567 /* Zero extend the operand. */
3568 ax_zero_ext (expr
, addr_size_bits
);
3569 i
= ax_goto (expr
, aop_if_goto
);
3570 dw_labels
.push_back (op_ptr
+ offset
- base
);
3571 patches
.push_back (i
);
3578 case DW_OP_bit_piece
:
3580 uint64_t size
, offset
;
3582 if (op_ptr
- 1 == previous_piece
)
3583 error (_("Cannot translate empty pieces to agent expressions"));
3584 previous_piece
= op_ptr
- 1;
3586 op_ptr
= safe_read_uleb128 (op_ptr
, op_end
, &size
);
3587 if (op
== DW_OP_piece
)
3593 op_ptr
= safe_read_uleb128 (op_ptr
, op_end
, &offset
);
3595 if (bits_collected
+ size
> 8 * sizeof (LONGEST
))
3596 error (_("Expression pieces exceed word size"));
3598 /* Access the bits. */
3601 case axs_lvalue_register
:
3602 ax_reg (expr
, loc
->u
.reg
);
3605 case axs_lvalue_memory
:
3606 /* Offset the pointer, if needed. */
3609 ax_const_l (expr
, offset
/ 8);
3610 ax_simple (expr
, aop_add
);
3613 access_memory (arch
, expr
, size
);
3617 /* For a bits-big-endian target, shift up what we already
3618 have. For a bits-little-endian target, shift up the
3619 new data. Note that there is a potential bug here if
3620 the DWARF expression leaves multiple values on the
3622 if (bits_collected
> 0)
3624 if (bits_big_endian
)
3626 ax_simple (expr
, aop_swap
);
3627 ax_const_l (expr
, size
);
3628 ax_simple (expr
, aop_lsh
);
3629 /* We don't need a second swap here, because
3630 aop_bit_or is symmetric. */
3634 ax_const_l (expr
, size
);
3635 ax_simple (expr
, aop_lsh
);
3637 ax_simple (expr
, aop_bit_or
);
3640 bits_collected
+= size
;
3641 loc
->kind
= axs_rvalue
;
3645 case DW_OP_GNU_uninit
:
3651 struct dwarf2_locexpr_baton block
;
3652 int size
= (op
== DW_OP_call2
? 2 : 4);
3654 uoffset
= extract_unsigned_integer (op_ptr
, size
, byte_order
);
3657 cu_offset offset
= (cu_offset
) uoffset
;
3658 block
= dwarf2_fetch_die_loc_cu_off (offset
, per_cu
,
3661 /* DW_OP_call_ref is currently not supported. */
3662 gdb_assert (block
.per_cu
== per_cu
);
3664 dwarf2_compile_expr_to_ax (expr
, loc
, arch
, addr_size
,
3665 block
.data
, block
.data
+ block
.size
,
3670 case DW_OP_call_ref
:
3678 /* Patch all the branches we emitted. */
3679 for (i
= 0; i
< patches
.size (); ++i
)
3681 int targ
= offsets
[dw_labels
[i
]];
3683 internal_error (__FILE__
, __LINE__
, _("invalid label"));
3684 ax_label (expr
, patches
[i
], targ
);
3689 /* Return the value of SYMBOL in FRAME using the DWARF-2 expression
3690 evaluator to calculate the location. */
3691 static struct value
*
3692 locexpr_read_variable (struct symbol
*symbol
, struct frame_info
*frame
)
3694 struct dwarf2_locexpr_baton
*dlbaton
3695 = (struct dwarf2_locexpr_baton
*) SYMBOL_LOCATION_BATON (symbol
);
3698 val
= dwarf2_evaluate_loc_desc (SYMBOL_TYPE (symbol
), frame
, dlbaton
->data
,
3699 dlbaton
->size
, dlbaton
->per_cu
);
3704 /* Return the value of SYMBOL in FRAME at (callee) FRAME's function
3705 entry. SYMBOL should be a function parameter, otherwise NO_ENTRY_VALUE_ERROR
3708 static struct value
*
3709 locexpr_read_variable_at_entry (struct symbol
*symbol
, struct frame_info
*frame
)
3711 struct dwarf2_locexpr_baton
*dlbaton
3712 = (struct dwarf2_locexpr_baton
*) SYMBOL_LOCATION_BATON (symbol
);
3714 return value_of_dwarf_block_entry (SYMBOL_TYPE (symbol
), frame
, dlbaton
->data
,
3718 /* Implementation of get_symbol_read_needs from
3719 symbol_computed_ops. */
3721 static enum symbol_needs_kind
3722 locexpr_get_symbol_read_needs (struct symbol
*symbol
)
3724 struct dwarf2_locexpr_baton
*dlbaton
3725 = (struct dwarf2_locexpr_baton
*) SYMBOL_LOCATION_BATON (symbol
);
3727 return dwarf2_loc_desc_get_symbol_read_needs (dlbaton
->data
, dlbaton
->size
,
3731 /* Return true if DATA points to the end of a piece. END is one past
3732 the last byte in the expression. */
3735 piece_end_p (const gdb_byte
*data
, const gdb_byte
*end
)
3737 return data
== end
|| data
[0] == DW_OP_piece
|| data
[0] == DW_OP_bit_piece
;
3740 /* Helper for locexpr_describe_location_piece that finds the name of a
3744 locexpr_regname (struct gdbarch
*gdbarch
, int dwarf_regnum
)
3748 /* This doesn't use dwarf_reg_to_regnum_or_error on purpose.
3749 We'd rather print *something* here than throw an error. */
3750 regnum
= dwarf_reg_to_regnum (gdbarch
, dwarf_regnum
);
3751 /* gdbarch_register_name may just return "", return something more
3752 descriptive for bad register numbers. */
3755 /* The text is output as "$bad_register_number".
3756 That is why we use the underscores. */
3757 return _("bad_register_number");
3759 return gdbarch_register_name (gdbarch
, regnum
);
3762 /* Nicely describe a single piece of a location, returning an updated
3763 position in the bytecode sequence. This function cannot recognize
3764 all locations; if a location is not recognized, it simply returns
3765 DATA. If there is an error during reading, e.g. we run off the end
3766 of the buffer, an error is thrown. */
3768 static const gdb_byte
*
3769 locexpr_describe_location_piece (struct symbol
*symbol
, struct ui_file
*stream
,
3770 CORE_ADDR addr
, struct objfile
*objfile
,
3771 struct dwarf2_per_cu_data
*per_cu
,
3772 const gdb_byte
*data
, const gdb_byte
*end
,
3773 unsigned int addr_size
)
3775 struct gdbarch
*gdbarch
= get_objfile_arch (objfile
);
3778 if (data
[0] >= DW_OP_reg0
&& data
[0] <= DW_OP_reg31
)
3780 fprintf_filtered (stream
, _("a variable in $%s"),
3781 locexpr_regname (gdbarch
, data
[0] - DW_OP_reg0
));
3784 else if (data
[0] == DW_OP_regx
)
3788 data
= safe_read_uleb128 (data
+ 1, end
, ®
);
3789 fprintf_filtered (stream
, _("a variable in $%s"),
3790 locexpr_regname (gdbarch
, reg
));
3792 else if (data
[0] == DW_OP_fbreg
)
3794 const struct block
*b
;
3795 struct symbol
*framefunc
;
3797 int64_t frame_offset
;
3798 const gdb_byte
*base_data
, *new_data
, *save_data
= data
;
3800 int64_t base_offset
= 0;
3802 new_data
= safe_read_sleb128 (data
+ 1, end
, &frame_offset
);
3803 if (!piece_end_p (new_data
, end
))
3807 b
= block_for_pc (addr
);
3810 error (_("No block found for address for symbol \"%s\"."),
3811 SYMBOL_PRINT_NAME (symbol
));
3813 framefunc
= block_linkage_function (b
);
3816 error (_("No function found for block for symbol \"%s\"."),
3817 SYMBOL_PRINT_NAME (symbol
));
3819 func_get_frame_base_dwarf_block (framefunc
, addr
, &base_data
, &base_size
);
3821 if (base_data
[0] >= DW_OP_breg0
&& base_data
[0] <= DW_OP_breg31
)
3823 const gdb_byte
*buf_end
;
3825 frame_reg
= base_data
[0] - DW_OP_breg0
;
3826 buf_end
= safe_read_sleb128 (base_data
+ 1, base_data
+ base_size
,
3828 if (buf_end
!= base_data
+ base_size
)
3829 error (_("Unexpected opcode after "
3830 "DW_OP_breg%u for symbol \"%s\"."),
3831 frame_reg
, SYMBOL_PRINT_NAME (symbol
));
3833 else if (base_data
[0] >= DW_OP_reg0
&& base_data
[0] <= DW_OP_reg31
)
3835 /* The frame base is just the register, with no offset. */
3836 frame_reg
= base_data
[0] - DW_OP_reg0
;
3841 /* We don't know what to do with the frame base expression,
3842 so we can't trace this variable; give up. */
3846 fprintf_filtered (stream
,
3847 _("a variable at frame base reg $%s offset %s+%s"),
3848 locexpr_regname (gdbarch
, frame_reg
),
3849 plongest (base_offset
), plongest (frame_offset
));
3851 else if (data
[0] >= DW_OP_breg0
&& data
[0] <= DW_OP_breg31
3852 && piece_end_p (data
, end
))
3856 data
= safe_read_sleb128 (data
+ 1, end
, &offset
);
3858 fprintf_filtered (stream
,
3859 _("a variable at offset %s from base reg $%s"),
3861 locexpr_regname (gdbarch
, data
[0] - DW_OP_breg0
));
3864 /* The location expression for a TLS variable looks like this (on a
3867 DW_AT_location : 10 byte block: 3 4 0 0 0 0 0 0 0 e0
3868 (DW_OP_addr: 4; DW_OP_GNU_push_tls_address)
3870 0x3 is the encoding for DW_OP_addr, which has an operand as long
3871 as the size of an address on the target machine (here is 8
3872 bytes). Note that more recent version of GCC emit DW_OP_const4u
3873 or DW_OP_const8u, depending on address size, rather than
3874 DW_OP_addr. 0xe0 is the encoding for DW_OP_GNU_push_tls_address.
3875 The operand represents the offset at which the variable is within
3876 the thread local storage. */
3878 else if (data
+ 1 + addr_size
< end
3879 && (data
[0] == DW_OP_addr
3880 || (addr_size
== 4 && data
[0] == DW_OP_const4u
)
3881 || (addr_size
== 8 && data
[0] == DW_OP_const8u
))
3882 && (data
[1 + addr_size
] == DW_OP_GNU_push_tls_address
3883 || data
[1 + addr_size
] == DW_OP_form_tls_address
)
3884 && piece_end_p (data
+ 2 + addr_size
, end
))
3887 offset
= extract_unsigned_integer (data
+ 1, addr_size
,
3888 gdbarch_byte_order (gdbarch
));
3890 fprintf_filtered (stream
,
3891 _("a thread-local variable at offset 0x%s "
3892 "in the thread-local storage for `%s'"),
3893 phex_nz (offset
, addr_size
), objfile_name (objfile
));
3895 data
+= 1 + addr_size
+ 1;
3898 /* With -gsplit-dwarf a TLS variable can also look like this:
3899 DW_AT_location : 3 byte block: fc 4 e0
3900 (DW_OP_GNU_const_index: 4;
3901 DW_OP_GNU_push_tls_address) */
3902 else if (data
+ 3 <= end
3903 && data
+ 1 + (leb128_size
= skip_leb128 (data
+ 1, end
)) < end
3904 && data
[0] == DW_OP_GNU_const_index
3906 && (data
[1 + leb128_size
] == DW_OP_GNU_push_tls_address
3907 || data
[1 + leb128_size
] == DW_OP_form_tls_address
)
3908 && piece_end_p (data
+ 2 + leb128_size
, end
))
3912 data
= safe_read_uleb128 (data
+ 1, end
, &offset
);
3913 offset
= dwarf2_read_addr_index (per_cu
, offset
);
3914 fprintf_filtered (stream
,
3915 _("a thread-local variable at offset 0x%s "
3916 "in the thread-local storage for `%s'"),
3917 phex_nz (offset
, addr_size
), objfile_name (objfile
));
3921 else if (data
[0] >= DW_OP_lit0
3922 && data
[0] <= DW_OP_lit31
3924 && data
[1] == DW_OP_stack_value
)
3926 fprintf_filtered (stream
, _("the constant %d"), data
[0] - DW_OP_lit0
);
3933 /* Disassemble an expression, stopping at the end of a piece or at the
3934 end of the expression. Returns a pointer to the next unread byte
3935 in the input expression. If ALL is nonzero, then this function
3936 will keep going until it reaches the end of the expression.
3937 If there is an error during reading, e.g. we run off the end
3938 of the buffer, an error is thrown. */
3940 static const gdb_byte
*
3941 disassemble_dwarf_expression (struct ui_file
*stream
,
3942 struct gdbarch
*arch
, unsigned int addr_size
,
3943 int offset_size
, const gdb_byte
*start
,
3944 const gdb_byte
*data
, const gdb_byte
*end
,
3945 int indent
, int all
,
3946 struct dwarf2_per_cu_data
*per_cu
)
3950 || (data
[0] != DW_OP_piece
&& data
[0] != DW_OP_bit_piece
)))
3952 enum dwarf_location_atom op
= (enum dwarf_location_atom
) *data
++;
3957 name
= get_DW_OP_name (op
);
3960 error (_("Unrecognized DWARF opcode 0x%02x at %ld"),
3961 op
, (long) (data
- 1 - start
));
3962 fprintf_filtered (stream
, " %*ld: %s", indent
+ 4,
3963 (long) (data
- 1 - start
), name
);
3968 ul
= extract_unsigned_integer (data
, addr_size
,
3969 gdbarch_byte_order (arch
));
3971 fprintf_filtered (stream
, " 0x%s", phex_nz (ul
, addr_size
));
3975 ul
= extract_unsigned_integer (data
, 1, gdbarch_byte_order (arch
));
3977 fprintf_filtered (stream
, " %s", pulongest (ul
));
3980 l
= extract_signed_integer (data
, 1, gdbarch_byte_order (arch
));
3982 fprintf_filtered (stream
, " %s", plongest (l
));
3985 ul
= extract_unsigned_integer (data
, 2, gdbarch_byte_order (arch
));
3987 fprintf_filtered (stream
, " %s", pulongest (ul
));
3990 l
= extract_signed_integer (data
, 2, gdbarch_byte_order (arch
));
3992 fprintf_filtered (stream
, " %s", plongest (l
));
3995 ul
= extract_unsigned_integer (data
, 4, gdbarch_byte_order (arch
));
3997 fprintf_filtered (stream
, " %s", pulongest (ul
));
4000 l
= extract_signed_integer (data
, 4, gdbarch_byte_order (arch
));
4002 fprintf_filtered (stream
, " %s", plongest (l
));
4005 ul
= extract_unsigned_integer (data
, 8, gdbarch_byte_order (arch
));
4007 fprintf_filtered (stream
, " %s", pulongest (ul
));
4010 l
= extract_signed_integer (data
, 8, gdbarch_byte_order (arch
));
4012 fprintf_filtered (stream
, " %s", plongest (l
));
4015 data
= safe_read_uleb128 (data
, end
, &ul
);
4016 fprintf_filtered (stream
, " %s", pulongest (ul
));
4019 data
= safe_read_sleb128 (data
, end
, &l
);
4020 fprintf_filtered (stream
, " %s", plongest (l
));
4055 fprintf_filtered (stream
, " [$%s]",
4056 locexpr_regname (arch
, op
- DW_OP_reg0
));
4060 data
= safe_read_uleb128 (data
, end
, &ul
);
4061 fprintf_filtered (stream
, " %s [$%s]", pulongest (ul
),
4062 locexpr_regname (arch
, (int) ul
));
4065 case DW_OP_implicit_value
:
4066 data
= safe_read_uleb128 (data
, end
, &ul
);
4068 fprintf_filtered (stream
, " %s", pulongest (ul
));
4103 data
= safe_read_sleb128 (data
, end
, &l
);
4104 fprintf_filtered (stream
, " %s [$%s]", plongest (l
),
4105 locexpr_regname (arch
, op
- DW_OP_breg0
));
4109 data
= safe_read_uleb128 (data
, end
, &ul
);
4110 data
= safe_read_sleb128 (data
, end
, &l
);
4111 fprintf_filtered (stream
, " register %s [$%s] offset %s",
4113 locexpr_regname (arch
, (int) ul
),
4118 data
= safe_read_sleb128 (data
, end
, &l
);
4119 fprintf_filtered (stream
, " %s", plongest (l
));
4122 case DW_OP_xderef_size
:
4123 case DW_OP_deref_size
:
4125 fprintf_filtered (stream
, " %d", *data
);
4129 case DW_OP_plus_uconst
:
4130 data
= safe_read_uleb128 (data
, end
, &ul
);
4131 fprintf_filtered (stream
, " %s", pulongest (ul
));
4135 l
= extract_signed_integer (data
, 2, gdbarch_byte_order (arch
));
4137 fprintf_filtered (stream
, " to %ld",
4138 (long) (data
+ l
- start
));
4142 l
= extract_signed_integer (data
, 2, gdbarch_byte_order (arch
));
4144 fprintf_filtered (stream
, " %ld",
4145 (long) (data
+ l
- start
));
4149 ul
= extract_unsigned_integer (data
, 2, gdbarch_byte_order (arch
));
4151 fprintf_filtered (stream
, " offset %s", phex_nz (ul
, 2));
4155 ul
= extract_unsigned_integer (data
, 4, gdbarch_byte_order (arch
));
4157 fprintf_filtered (stream
, " offset %s", phex_nz (ul
, 4));
4160 case DW_OP_call_ref
:
4161 ul
= extract_unsigned_integer (data
, offset_size
,
4162 gdbarch_byte_order (arch
));
4163 data
+= offset_size
;
4164 fprintf_filtered (stream
, " offset %s", phex_nz (ul
, offset_size
));
4168 data
= safe_read_uleb128 (data
, end
, &ul
);
4169 fprintf_filtered (stream
, " %s (bytes)", pulongest (ul
));
4172 case DW_OP_bit_piece
:
4176 data
= safe_read_uleb128 (data
, end
, &ul
);
4177 data
= safe_read_uleb128 (data
, end
, &offset
);
4178 fprintf_filtered (stream
, " size %s offset %s (bits)",
4179 pulongest (ul
), pulongest (offset
));
4183 case DW_OP_implicit_pointer
:
4184 case DW_OP_GNU_implicit_pointer
:
4186 ul
= extract_unsigned_integer (data
, offset_size
,
4187 gdbarch_byte_order (arch
));
4188 data
+= offset_size
;
4190 data
= safe_read_sleb128 (data
, end
, &l
);
4192 fprintf_filtered (stream
, " DIE %s offset %s",
4193 phex_nz (ul
, offset_size
),
4198 case DW_OP_deref_type
:
4199 case DW_OP_GNU_deref_type
:
4201 int addr_size
= *data
++;
4204 data
= safe_read_uleb128 (data
, end
, &ul
);
4205 cu_offset offset
= (cu_offset
) ul
;
4206 type
= dwarf2_get_die_type (offset
, per_cu
);
4207 fprintf_filtered (stream
, "<");
4208 type_print (type
, "", stream
, -1);
4209 fprintf_filtered (stream
, " [0x%s]> %d",
4210 phex_nz (to_underlying (offset
), 0),
4215 case DW_OP_const_type
:
4216 case DW_OP_GNU_const_type
:
4220 data
= safe_read_uleb128 (data
, end
, &ul
);
4221 cu_offset type_die
= (cu_offset
) ul
;
4222 type
= dwarf2_get_die_type (type_die
, per_cu
);
4223 fprintf_filtered (stream
, "<");
4224 type_print (type
, "", stream
, -1);
4225 fprintf_filtered (stream
, " [0x%s]>",
4226 phex_nz (to_underlying (type_die
), 0));
4230 case DW_OP_regval_type
:
4231 case DW_OP_GNU_regval_type
:
4236 data
= safe_read_uleb128 (data
, end
, ®
);
4237 data
= safe_read_uleb128 (data
, end
, &ul
);
4238 cu_offset type_die
= (cu_offset
) ul
;
4240 type
= dwarf2_get_die_type (type_die
, per_cu
);
4241 fprintf_filtered (stream
, "<");
4242 type_print (type
, "", stream
, -1);
4243 fprintf_filtered (stream
, " [0x%s]> [$%s]",
4244 phex_nz (to_underlying (type_die
), 0),
4245 locexpr_regname (arch
, reg
));
4250 case DW_OP_GNU_convert
:
4251 case DW_OP_reinterpret
:
4252 case DW_OP_GNU_reinterpret
:
4254 data
= safe_read_uleb128 (data
, end
, &ul
);
4255 cu_offset type_die
= (cu_offset
) ul
;
4257 if (to_underlying (type_die
) == 0)
4258 fprintf_filtered (stream
, "<0>");
4263 type
= dwarf2_get_die_type (type_die
, per_cu
);
4264 fprintf_filtered (stream
, "<");
4265 type_print (type
, "", stream
, -1);
4266 fprintf_filtered (stream
, " [0x%s]>",
4267 phex_nz (to_underlying (type_die
), 0));
4272 case DW_OP_entry_value
:
4273 case DW_OP_GNU_entry_value
:
4274 data
= safe_read_uleb128 (data
, end
, &ul
);
4275 fputc_filtered ('\n', stream
);
4276 disassemble_dwarf_expression (stream
, arch
, addr_size
, offset_size
,
4277 start
, data
, data
+ ul
, indent
+ 2,
4282 case DW_OP_GNU_parameter_ref
:
4283 ul
= extract_unsigned_integer (data
, 4, gdbarch_byte_order (arch
));
4285 fprintf_filtered (stream
, " offset %s", phex_nz (ul
, 4));
4288 case DW_OP_GNU_addr_index
:
4289 data
= safe_read_uleb128 (data
, end
, &ul
);
4290 ul
= dwarf2_read_addr_index (per_cu
, ul
);
4291 fprintf_filtered (stream
, " 0x%s", phex_nz (ul
, addr_size
));
4293 case DW_OP_GNU_const_index
:
4294 data
= safe_read_uleb128 (data
, end
, &ul
);
4295 ul
= dwarf2_read_addr_index (per_cu
, ul
);
4296 fprintf_filtered (stream
, " %s", pulongest (ul
));
4300 fprintf_filtered (stream
, "\n");
4306 /* Describe a single location, which may in turn consist of multiple
4310 locexpr_describe_location_1 (struct symbol
*symbol
, CORE_ADDR addr
,
4311 struct ui_file
*stream
,
4312 const gdb_byte
*data
, size_t size
,
4313 struct objfile
*objfile
, unsigned int addr_size
,
4314 int offset_size
, struct dwarf2_per_cu_data
*per_cu
)
4316 const gdb_byte
*end
= data
+ size
;
4317 int first_piece
= 1, bad
= 0;
4321 const gdb_byte
*here
= data
;
4322 int disassemble
= 1;
4327 fprintf_filtered (stream
, _(", and "));
4329 if (!dwarf_always_disassemble
)
4331 data
= locexpr_describe_location_piece (symbol
, stream
,
4332 addr
, objfile
, per_cu
,
4333 data
, end
, addr_size
);
4334 /* If we printed anything, or if we have an empty piece,
4335 then don't disassemble. */
4337 || data
[0] == DW_OP_piece
4338 || data
[0] == DW_OP_bit_piece
)
4343 fprintf_filtered (stream
, _("a complex DWARF expression:\n"));
4344 data
= disassemble_dwarf_expression (stream
,
4345 get_objfile_arch (objfile
),
4346 addr_size
, offset_size
, data
,
4348 dwarf_always_disassemble
,
4354 int empty
= data
== here
;
4357 fprintf_filtered (stream
, " ");
4358 if (data
[0] == DW_OP_piece
)
4362 data
= safe_read_uleb128 (data
+ 1, end
, &bytes
);
4365 fprintf_filtered (stream
, _("an empty %s-byte piece"),
4368 fprintf_filtered (stream
, _(" [%s-byte piece]"),
4371 else if (data
[0] == DW_OP_bit_piece
)
4373 uint64_t bits
, offset
;
4375 data
= safe_read_uleb128 (data
+ 1, end
, &bits
);
4376 data
= safe_read_uleb128 (data
, end
, &offset
);
4379 fprintf_filtered (stream
,
4380 _("an empty %s-bit piece"),
4383 fprintf_filtered (stream
,
4384 _(" [%s-bit piece, offset %s bits]"),
4385 pulongest (bits
), pulongest (offset
));
4395 if (bad
|| data
> end
)
4396 error (_("Corrupted DWARF2 expression for \"%s\"."),
4397 SYMBOL_PRINT_NAME (symbol
));
4400 /* Print a natural-language description of SYMBOL to STREAM. This
4401 version is for a symbol with a single location. */
4404 locexpr_describe_location (struct symbol
*symbol
, CORE_ADDR addr
,
4405 struct ui_file
*stream
)
4407 struct dwarf2_locexpr_baton
*dlbaton
4408 = (struct dwarf2_locexpr_baton
*) SYMBOL_LOCATION_BATON (symbol
);
4409 struct objfile
*objfile
= dwarf2_per_cu_objfile (dlbaton
->per_cu
);
4410 unsigned int addr_size
= dwarf2_per_cu_addr_size (dlbaton
->per_cu
);
4411 int offset_size
= dwarf2_per_cu_offset_size (dlbaton
->per_cu
);
4413 locexpr_describe_location_1 (symbol
, addr
, stream
,
4414 dlbaton
->data
, dlbaton
->size
,
4415 objfile
, addr_size
, offset_size
,
4419 /* Describe the location of SYMBOL as an agent value in VALUE, generating
4420 any necessary bytecode in AX. */
4423 locexpr_tracepoint_var_ref (struct symbol
*symbol
, struct gdbarch
*gdbarch
,
4424 struct agent_expr
*ax
, struct axs_value
*value
)
4426 struct dwarf2_locexpr_baton
*dlbaton
4427 = (struct dwarf2_locexpr_baton
*) SYMBOL_LOCATION_BATON (symbol
);
4428 unsigned int addr_size
= dwarf2_per_cu_addr_size (dlbaton
->per_cu
);
4430 if (dlbaton
->size
== 0)
4431 value
->optimized_out
= 1;
4433 dwarf2_compile_expr_to_ax (ax
, value
, gdbarch
, addr_size
,
4434 dlbaton
->data
, dlbaton
->data
+ dlbaton
->size
,
4438 /* symbol_computed_ops 'generate_c_location' method. */
4441 locexpr_generate_c_location (struct symbol
*sym
, string_file
&stream
,
4442 struct gdbarch
*gdbarch
,
4443 unsigned char *registers_used
,
4444 CORE_ADDR pc
, const char *result_name
)
4446 struct dwarf2_locexpr_baton
*dlbaton
4447 = (struct dwarf2_locexpr_baton
*) SYMBOL_LOCATION_BATON (sym
);
4448 unsigned int addr_size
= dwarf2_per_cu_addr_size (dlbaton
->per_cu
);
4450 if (dlbaton
->size
== 0)
4451 error (_("symbol \"%s\" is optimized out"), SYMBOL_NATURAL_NAME (sym
));
4453 compile_dwarf_expr_to_c (stream
, result_name
,
4454 sym
, pc
, gdbarch
, registers_used
, addr_size
,
4455 dlbaton
->data
, dlbaton
->data
+ dlbaton
->size
,
4459 /* The set of location functions used with the DWARF-2 expression
4461 const struct symbol_computed_ops dwarf2_locexpr_funcs
= {
4462 locexpr_read_variable
,
4463 locexpr_read_variable_at_entry
,
4464 locexpr_get_symbol_read_needs
,
4465 locexpr_describe_location
,
4466 0, /* location_has_loclist */
4467 locexpr_tracepoint_var_ref
,
4468 locexpr_generate_c_location
4472 /* Wrapper functions for location lists. These generally find
4473 the appropriate location expression and call something above. */
4475 /* Return the value of SYMBOL in FRAME using the DWARF-2 expression
4476 evaluator to calculate the location. */
4477 static struct value
*
4478 loclist_read_variable (struct symbol
*symbol
, struct frame_info
*frame
)
4480 struct dwarf2_loclist_baton
*dlbaton
4481 = (struct dwarf2_loclist_baton
*) SYMBOL_LOCATION_BATON (symbol
);
4483 const gdb_byte
*data
;
4485 CORE_ADDR pc
= frame
? get_frame_address_in_block (frame
) : 0;
4487 data
= dwarf2_find_location_expression (dlbaton
, &size
, pc
);
4488 val
= dwarf2_evaluate_loc_desc (SYMBOL_TYPE (symbol
), frame
, data
, size
,
4494 /* Read variable SYMBOL like loclist_read_variable at (callee) FRAME's function
4495 entry. SYMBOL should be a function parameter, otherwise NO_ENTRY_VALUE_ERROR
4498 Function always returns non-NULL value, it may be marked optimized out if
4499 inferior frame information is not available. It throws NO_ENTRY_VALUE_ERROR
4500 if it cannot resolve the parameter for any reason. */
4502 static struct value
*
4503 loclist_read_variable_at_entry (struct symbol
*symbol
, struct frame_info
*frame
)
4505 struct dwarf2_loclist_baton
*dlbaton
4506 = (struct dwarf2_loclist_baton
*) SYMBOL_LOCATION_BATON (symbol
);
4507 const gdb_byte
*data
;
4511 if (frame
== NULL
|| !get_frame_func_if_available (frame
, &pc
))
4512 return allocate_optimized_out_value (SYMBOL_TYPE (symbol
));
4514 data
= dwarf2_find_location_expression (dlbaton
, &size
, pc
);
4516 return allocate_optimized_out_value (SYMBOL_TYPE (symbol
));
4518 return value_of_dwarf_block_entry (SYMBOL_TYPE (symbol
), frame
, data
, size
);
4521 /* Implementation of get_symbol_read_needs from
4522 symbol_computed_ops. */
4524 static enum symbol_needs_kind
4525 loclist_symbol_needs (struct symbol
*symbol
)
4527 /* If there's a location list, then assume we need to have a frame
4528 to choose the appropriate location expression. With tracking of
4529 global variables this is not necessarily true, but such tracking
4530 is disabled in GCC at the moment until we figure out how to
4533 return SYMBOL_NEEDS_FRAME
;
4536 /* Print a natural-language description of SYMBOL to STREAM. This
4537 version applies when there is a list of different locations, each
4538 with a specified address range. */
4541 loclist_describe_location (struct symbol
*symbol
, CORE_ADDR addr
,
4542 struct ui_file
*stream
)
4544 struct dwarf2_loclist_baton
*dlbaton
4545 = (struct dwarf2_loclist_baton
*) SYMBOL_LOCATION_BATON (symbol
);
4546 const gdb_byte
*loc_ptr
, *buf_end
;
4547 struct objfile
*objfile
= dwarf2_per_cu_objfile (dlbaton
->per_cu
);
4548 struct gdbarch
*gdbarch
= get_objfile_arch (objfile
);
4549 enum bfd_endian byte_order
= gdbarch_byte_order (gdbarch
);
4550 unsigned int addr_size
= dwarf2_per_cu_addr_size (dlbaton
->per_cu
);
4551 int offset_size
= dwarf2_per_cu_offset_size (dlbaton
->per_cu
);
4552 int signed_addr_p
= bfd_get_sign_extend_vma (objfile
->obfd
);
4553 /* Adjust base_address for relocatable objects. */
4554 CORE_ADDR base_offset
= dwarf2_per_cu_text_offset (dlbaton
->per_cu
);
4555 CORE_ADDR base_address
= dlbaton
->base_address
+ base_offset
;
4558 loc_ptr
= dlbaton
->data
;
4559 buf_end
= dlbaton
->data
+ dlbaton
->size
;
4561 fprintf_filtered (stream
, _("multi-location:\n"));
4563 /* Iterate through locations until we run out. */
4566 CORE_ADDR low
= 0, high
= 0; /* init for gcc -Wall */
4568 enum debug_loc_kind kind
;
4569 const gdb_byte
*new_ptr
= NULL
; /* init for gcc -Wall */
4571 if (dlbaton
->from_dwo
)
4572 kind
= decode_debug_loc_dwo_addresses (dlbaton
->per_cu
,
4573 loc_ptr
, buf_end
, &new_ptr
,
4574 &low
, &high
, byte_order
);
4576 kind
= decode_debug_loc_addresses (loc_ptr
, buf_end
, &new_ptr
,
4578 byte_order
, addr_size
,
4583 case DEBUG_LOC_END_OF_LIST
:
4586 case DEBUG_LOC_BASE_ADDRESS
:
4587 base_address
= high
+ base_offset
;
4588 fprintf_filtered (stream
, _(" Base address %s"),
4589 paddress (gdbarch
, base_address
));
4591 case DEBUG_LOC_START_END
:
4592 case DEBUG_LOC_START_LENGTH
:
4594 case DEBUG_LOC_BUFFER_OVERFLOW
:
4595 case DEBUG_LOC_INVALID_ENTRY
:
4596 error (_("Corrupted DWARF expression for symbol \"%s\"."),
4597 SYMBOL_PRINT_NAME (symbol
));
4599 gdb_assert_not_reached ("bad debug_loc_kind");
4602 /* Otherwise, a location expression entry. */
4603 low
+= base_address
;
4604 high
+= base_address
;
4606 low
= gdbarch_adjust_dwarf2_addr (gdbarch
, low
);
4607 high
= gdbarch_adjust_dwarf2_addr (gdbarch
, high
);
4609 length
= extract_unsigned_integer (loc_ptr
, 2, byte_order
);
4612 /* (It would improve readability to print only the minimum
4613 necessary digits of the second number of the range.) */
4614 fprintf_filtered (stream
, _(" Range %s-%s: "),
4615 paddress (gdbarch
, low
), paddress (gdbarch
, high
));
4617 /* Now describe this particular location. */
4618 locexpr_describe_location_1 (symbol
, low
, stream
, loc_ptr
, length
,
4619 objfile
, addr_size
, offset_size
,
4622 fprintf_filtered (stream
, "\n");
4628 /* Describe the location of SYMBOL as an agent value in VALUE, generating
4629 any necessary bytecode in AX. */
4631 loclist_tracepoint_var_ref (struct symbol
*symbol
, struct gdbarch
*gdbarch
,
4632 struct agent_expr
*ax
, struct axs_value
*value
)
4634 struct dwarf2_loclist_baton
*dlbaton
4635 = (struct dwarf2_loclist_baton
*) SYMBOL_LOCATION_BATON (symbol
);
4636 const gdb_byte
*data
;
4638 unsigned int addr_size
= dwarf2_per_cu_addr_size (dlbaton
->per_cu
);
4640 data
= dwarf2_find_location_expression (dlbaton
, &size
, ax
->scope
);
4642 value
->optimized_out
= 1;
4644 dwarf2_compile_expr_to_ax (ax
, value
, gdbarch
, addr_size
, data
, data
+ size
,
4648 /* symbol_computed_ops 'generate_c_location' method. */
4651 loclist_generate_c_location (struct symbol
*sym
, string_file
&stream
,
4652 struct gdbarch
*gdbarch
,
4653 unsigned char *registers_used
,
4654 CORE_ADDR pc
, const char *result_name
)
4656 struct dwarf2_loclist_baton
*dlbaton
4657 = (struct dwarf2_loclist_baton
*) SYMBOL_LOCATION_BATON (sym
);
4658 unsigned int addr_size
= dwarf2_per_cu_addr_size (dlbaton
->per_cu
);
4659 const gdb_byte
*data
;
4662 data
= dwarf2_find_location_expression (dlbaton
, &size
, pc
);
4664 error (_("symbol \"%s\" is optimized out"), SYMBOL_NATURAL_NAME (sym
));
4666 compile_dwarf_expr_to_c (stream
, result_name
,
4667 sym
, pc
, gdbarch
, registers_used
, addr_size
,
4672 /* The set of location functions used with the DWARF-2 expression
4673 evaluator and location lists. */
4674 const struct symbol_computed_ops dwarf2_loclist_funcs
= {
4675 loclist_read_variable
,
4676 loclist_read_variable_at_entry
,
4677 loclist_symbol_needs
,
4678 loclist_describe_location
,
4679 1, /* location_has_loclist */
4680 loclist_tracepoint_var_ref
,
4681 loclist_generate_c_location
4684 /* Provide a prototype to silence -Wmissing-prototypes. */
4685 extern initialize_file_ftype _initialize_dwarf2loc
;
4688 _initialize_dwarf2loc (void)
4690 add_setshow_zuinteger_cmd ("entry-values", class_maintenance
,
4691 &entry_values_debug
,
4692 _("Set entry values and tail call frames "
4694 _("Show entry values and tail call frames "
4696 _("When non-zero, the process of determining "
4697 "parameter values from function entry point "
4698 "and tail call frames will be printed."),
4700 show_entry_values_debug
,
4701 &setdebuglist
, &showdebuglist
);
4704 register_self_test (selftests::copy_bitwise_tests
);