1 /* Copyright (c) 2008-2014. The SimGrid Team.
2 * All rights reserved. */
4 /* This program is free software; you can redistribute it and/or modify it
5 * under the terms of the license (GNU LGPL) which comes with this package. */
10 #define DW_LANG_Objc DW_LANG_ObjC /* fix spelling error in older dwarf.h */
12 #include <elfutils/libdw.h>
14 #include <simgrid_config.h>
16 #include <xbt/sysdep.h>
18 #include "mc_object_info.h"
19 #include "mc_private.h"
23 static void MC_dwarf_register_global_variable(mc_object_info_t info, dw_variable_t variable);
24 static void MC_register_variable(mc_object_info_t info, dw_frame_t frame, dw_variable_t variable);
25 static void MC_dwarf_register_non_global_variable(mc_object_info_t info, dw_frame_t frame, dw_variable_t variable);
26 static void MC_dwarf_register_variable(mc_object_info_t info, dw_frame_t frame, dw_variable_t variable);
28 XBT_LOG_NEW_DEFAULT_SUBCATEGORY(mc_dwarf, mc, "DWARF processing");
30 /** \brief The default DW_TAG_lower_bound for a given DW_AT_language.
32 * The default for a given language is defined in the DWARF spec.
34 * \param language consant as defined by the DWARf spec
36 static uint64_t MC_dwarf_default_lower_bound(int lang);
38 /** \brief Computes the the element_count of a DW_TAG_enumeration_type DIE
40 * This is the number of elements in a given array dimension.
42 * A reference of the compilation unit (DW_TAG_compile_unit) is
43 * needed because the default lower bound (when there is no DW_AT_lower_bound)
44 * depends of the language of the compilation unit (DW_AT_language).
46 * \param die DIE for the DW_TAG_enumeration_type or DW_TAG_subrange_type
47 * \param unit DIE of the DW_TAG_compile_unit
49 static uint64_t MC_dwarf_subrange_element_count(Dwarf_Die * die,
52 /** \brief Computes the number of elements of a given DW_TAG_array_type.
54 * \param die DIE for the DW_TAG_array_type
56 static uint64_t MC_dwarf_array_element_count(Dwarf_Die * die, Dwarf_Die * unit);
58 /** \brief Process a DIE
60 * \param info the resulting object fot the library/binary file (output)
61 * \param die the current DIE
62 * \param unit the DIE of the compile unit of the current DIE
63 * \param frame containg frame if any
65 static void MC_dwarf_handle_die(mc_object_info_t info, Dwarf_Die * die,
66 Dwarf_Die * unit, dw_frame_t frame,
69 /** \brief Process a type DIE
71 static void MC_dwarf_handle_type_die(mc_object_info_t info, Dwarf_Die * die,
72 Dwarf_Die * unit, dw_frame_t frame,
75 /** \brief Calls MC_dwarf_handle_die on all childrend of the given die
77 * \param info the resulting object fot the library/binary file (output)
78 * \param die the current DIE
79 * \param unit the DIE of the compile unit of the current DIE
80 * \param frame containg frame if any
82 static void MC_dwarf_handle_children(mc_object_info_t info, Dwarf_Die * die,
83 Dwarf_Die * unit, dw_frame_t frame,
86 /** \brief Handle a variable (DW_TAG_variable or other)
88 * \param info the resulting object fot the library/binary file (output)
89 * \param die the current DIE
90 * \param unit the DIE of the compile unit of the current DIE
91 * \param frame containg frame if any
93 static void MC_dwarf_handle_variable_die(mc_object_info_t info, Dwarf_Die * die,
94 Dwarf_Die * unit, dw_frame_t frame,
97 /** \brief Get the DW_TAG_type of the DIE
100 * \return DW_TAG_type attribute as a new string (NULL if none)
102 static char *MC_dwarf_at_type(Dwarf_Die * die);
104 /** \brief Get the name of an attribute (DW_AT_*) from its code
106 * \param attr attribute code (see the DWARF specification)
107 * \return name of the attribute
109 const char *MC_dwarf_attrname(int attr)
112 #include "mc_dwarf_attrnames.h"
114 return "DW_AT_unknown";
118 /** \brief Get the name of a dwarf tag (DW_TAG_*) from its code
120 * \param tag tag code (see the DWARF specification)
121 * \return name of the tag
124 const char *MC_dwarf_tagname(int tag)
127 #include "mc_dwarf_tagnames.h"
129 return "DW_TAG_invalid";
131 return "DW_TAG_unknown";
135 /** \brief A class of DWARF tags (DW_TAG_*)
137 typedef enum mc_tag_class {
146 static mc_tag_class MC_dwarf_tag_classify(int tag)
150 case DW_TAG_array_type:
151 case DW_TAG_class_type:
152 case DW_TAG_enumeration_type:
154 case DW_TAG_pointer_type:
155 case DW_TAG_reference_type:
156 case DW_TAG_rvalue_reference_type:
157 case DW_TAG_string_type:
158 case DW_TAG_structure_type:
159 case DW_TAG_subroutine_type:
160 case DW_TAG_union_type:
161 case DW_TAG_ptr_to_member_type:
162 case DW_TAG_set_type:
163 case DW_TAG_subrange_type:
164 case DW_TAG_base_type:
165 case DW_TAG_const_type:
166 case DW_TAG_file_type:
167 case DW_TAG_packed_type:
168 case DW_TAG_volatile_type:
169 case DW_TAG_restrict_type:
170 case DW_TAG_interface_type:
171 case DW_TAG_unspecified_type:
172 case DW_TAG_shared_type:
175 case DW_TAG_subprogram:
176 return mc_tag_subprogram;
178 case DW_TAG_variable:
179 case DW_TAG_formal_parameter:
180 return mc_tag_variable;
182 case DW_TAG_lexical_block:
183 case DW_TAG_try_block:
184 case DW_TAG_catch_block:
185 case DW_TAG_inlined_subroutine:
186 case DW_TAG_with_stmt:
189 case DW_TAG_namespace:
190 return mc_tag_namespace;
193 return mc_tag_unknown;
198 #define MC_DW_CLASS_UNKNOWN 0
199 #define MC_DW_CLASS_ADDRESS 1 // Location in the address space of the program
200 #define MC_DW_CLASS_BLOCK 2 // Arbitrary block of bytes
201 #define MC_DW_CLASS_CONSTANT 3
202 #define MC_DW_CLASS_STRING 3 // String
203 #define MC_DW_CLASS_FLAG 4 // Boolean
204 #define MC_DW_CLASS_REFERENCE 5 // Reference to another DIE
205 #define MC_DW_CLASS_EXPRLOC 6 // DWARF expression/location description
206 #define MC_DW_CLASS_LINEPTR 7
207 #define MC_DW_CLASS_LOCLISTPTR 8
208 #define MC_DW_CLASS_MACPTR 9
209 #define MC_DW_CLASS_RANGELISTPTR 10
211 /** \brief Find the DWARF data class for a given DWARF data form
213 * This mapping is defined in the DWARF spec.
215 * \param form The form (values taken from the DWARF spec)
216 * \return An internal representation for the corresponding class
218 static int MC_dwarf_form_get_class(int form)
222 return MC_DW_CLASS_ADDRESS;
227 return MC_DW_CLASS_BLOCK;
234 return MC_DW_CLASS_CONSTANT;
237 return MC_DW_CLASS_STRING;
238 case DW_FORM_ref_addr:
243 case DW_FORM_ref_udata:
244 return MC_DW_CLASS_REFERENCE;
246 case DW_FORM_flag_present:
247 return MC_DW_CLASS_FLAG;
248 case DW_FORM_exprloc:
249 return MC_DW_CLASS_EXPRLOC;
253 return MC_DW_CLASS_UNKNOWN;
257 /** \brief Get the name of the tag of a given DIE
260 * \return name of the tag of this DIE
262 static inline const char *MC_dwarf_die_tagname(Dwarf_Die * die)
264 return MC_dwarf_tagname(dwarf_tag(die));
269 /** \brief Get an attribute of a given DIE as a string
272 * \param attribute attribute
273 * \return value of the given attribute of the given DIE
275 static const char *MC_dwarf_attr_integrate_string(Dwarf_Die * die,
278 Dwarf_Attribute attr;
279 if (!dwarf_attr_integrate(die, attribute, &attr)) {
282 return dwarf_formstring(&attr);
286 /** \brief Get the linkage name of a DIE.
288 * Use either DW_AT_linkage_name or DW_AT_MIPS_linkage_name.
289 * DW_AT_linkage_name is standardized since DWARF 4.
290 * Before this version of DWARF, the MIPS extensions
291 * DW_AT_MIPS_linkage_name is used (at least by GCC).
294 * \return linkage name of the given DIE (or NULL)
296 static const char *MC_dwarf_at_linkage_name(Dwarf_Die * die)
298 const char *name = MC_dwarf_attr_integrate_string(die, DW_AT_linkage_name);
300 name = MC_dwarf_attr_integrate_string(die, DW_AT_MIPS_linkage_name);
304 static Dwarf_Off MC_dwarf_attr_dieoffset(Dwarf_Die * die, int attribute)
306 Dwarf_Attribute attr;
307 if (dwarf_hasattr_integrate(die, attribute)) {
308 dwarf_attr_integrate(die, attribute, &attr);
309 Dwarf_Die subtype_die;
310 if (dwarf_formref_die(&attr, &subtype_die) == NULL) {
311 xbt_die("Could not find DIE");
313 return dwarf_dieoffset(&subtype_die);
318 static Dwarf_Off MC_dwarf_attr_integrate_dieoffset(Dwarf_Die * die,
321 Dwarf_Attribute attr;
322 if (dwarf_hasattr_integrate(die, attribute)) {
323 dwarf_attr_integrate(die, DW_AT_type, &attr);
324 Dwarf_Die subtype_die;
325 if (dwarf_formref_die(&attr, &subtype_die) == NULL) {
326 xbt_die("Could not find DIE");
328 return dwarf_dieoffset(&subtype_die);
333 /** \brief Find the type/subtype (DW_AT_type) for a DIE
336 * \return DW_AT_type reference as a global offset in hexadecimal (or NULL)
338 static char *MC_dwarf_at_type(Dwarf_Die * die)
340 Dwarf_Off offset = MC_dwarf_attr_integrate_dieoffset(die, DW_AT_type);
341 return offset == 0 ? NULL : bprintf("%" PRIx64, offset);
344 static uint64_t MC_dwarf_attr_integrate_addr(Dwarf_Die * die, int attribute)
346 Dwarf_Attribute attr;
347 if (dwarf_attr_integrate(die, attribute, &attr) == NULL)
350 if (dwarf_formaddr(&attr, &value) == 0)
351 return (uint64_t) value;
356 static uint64_t MC_dwarf_attr_integrate_uint(Dwarf_Die * die, int attribute,
357 uint64_t default_value)
359 Dwarf_Attribute attr;
360 if (dwarf_attr_integrate(die, attribute, &attr) == NULL)
361 return default_value;
363 return dwarf_formudata(dwarf_attr_integrate(die, attribute, &attr),
364 &value) == 0 ? (uint64_t) value : default_value;
367 static bool MC_dwarf_attr_flag(Dwarf_Die * die, int attribute, bool integrate)
369 Dwarf_Attribute attr;
370 if ((integrate ? dwarf_attr_integrate(die, attribute, &attr)
371 : dwarf_attr(die, attribute, &attr)) == 0)
375 if (dwarf_formflag(&attr, &result))
376 xbt_die("Unexpected form for attribute %s", MC_dwarf_attrname(attribute));
380 /** \brief Find the default lower bound for a given language
382 * The default lower bound of an array (when DW_TAG_lower_bound
383 * is missing) depends on the language of the compilation unit.
385 * \param lang Language of the compilation unit (values defined in the DWARF spec)
386 * \return Default lower bound of an array in this compilation unit
388 static uint64_t MC_dwarf_default_lower_bound(int lang)
394 case DW_LANG_C_plus_plus:
398 case DW_LANG_ObjC_plus_plus:
404 case DW_LANG_Fortran77:
405 case DW_LANG_Fortran90:
406 case DW_LANG_Fortran95:
407 case DW_LANG_Modula2:
408 case DW_LANG_Pascal83:
410 case DW_LANG_Cobol74:
411 case DW_LANG_Cobol85:
414 xbt_die("No default DW_TAG_lower_bound for language %i and none given",
420 /** \brief Finds the number of elements in a DW_TAG_subrange_type or DW_TAG_enumeration_type DIE
423 * \param unit DIE of the compilation unit
424 * \return number of elements in the range
426 static uint64_t MC_dwarf_subrange_element_count(Dwarf_Die * die,
429 xbt_assert(dwarf_tag(die) == DW_TAG_enumeration_type
430 || dwarf_tag(die) == DW_TAG_subrange_type,
431 "MC_dwarf_subrange_element_count called with DIE of type %s",
432 MC_dwarf_die_tagname(die));
434 // Use DW_TAG_count if present:
435 if (dwarf_hasattr_integrate(die, DW_AT_count)) {
436 return MC_dwarf_attr_integrate_uint(die, DW_AT_count, 0);
438 // Otherwise compute DW_TAG_upper_bound-DW_TAG_lower_bound + 1:
440 if (!dwarf_hasattr_integrate(die, DW_AT_upper_bound)) {
441 // This is not really 0, but the code expects this (we do not know):
444 uint64_t upper_bound =
445 MC_dwarf_attr_integrate_uint(die, DW_AT_upper_bound, -1);
447 uint64_t lower_bound = 0;
448 if (dwarf_hasattr_integrate(die, DW_AT_lower_bound)) {
449 lower_bound = MC_dwarf_attr_integrate_uint(die, DW_AT_lower_bound, -1);
451 lower_bound = MC_dwarf_default_lower_bound(dwarf_srclang(unit));
453 return upper_bound - lower_bound + 1;
456 /** \brief Finds the number of elements in a array type (DW_TAG_array_type)
458 * The compilation unit might be needed because the default lower
459 * bound depends on the language of the compilation unit.
461 * \param die the DIE of the DW_TAG_array_type
462 * \param unit the DIE of the compilation unit
463 * \return number of elements in this array type
465 static uint64_t MC_dwarf_array_element_count(Dwarf_Die * die, Dwarf_Die * unit)
467 xbt_assert(dwarf_tag(die) == DW_TAG_array_type,
468 "MC_dwarf_array_element_count called with DIE of type %s",
469 MC_dwarf_die_tagname(die));
474 for (res = dwarf_child(die, &child); res == 0;
475 res = dwarf_siblingof(&child, &child)) {
476 int child_tag = dwarf_tag(&child);
477 if (child_tag == DW_TAG_subrange_type
478 || child_tag == DW_TAG_enumeration_type) {
479 result *= MC_dwarf_subrange_element_count(&child, unit);
487 /** \brief Initialize the location of a member of a type
488 * (DW_AT_data_member_location of a DW_TAG_member).
490 * \param type a type (struct, class)
491 * \param member the member of the type
492 * \param child DIE of the member (DW_TAG_member)
494 static void MC_dwarf_fill_member_location(dw_type_t type, dw_type_t member,
497 if (dwarf_hasattr(child, DW_AT_data_bit_offset)) {
498 xbt_die("Can't groke DW_AT_data_bit_offset.");
501 if (!dwarf_hasattr_integrate(child, DW_AT_data_member_location)) {
502 if (type->type != DW_TAG_union_type) {
504 ("Missing DW_AT_data_member_location field in DW_TAG_member %s of type <%"
505 PRIx64 ">%s", member->name, (uint64_t) type->id, type->name);
511 Dwarf_Attribute attr;
512 dwarf_attr_integrate(child, DW_AT_data_member_location, &attr);
513 int form = dwarf_whatform(&attr);
514 int klass = MC_dwarf_form_get_class(form);
516 case MC_DW_CLASS_EXPRLOC:
517 case MC_DW_CLASS_BLOCK:
518 // Location expression:
522 if (dwarf_getlocation(&attr, &expr, &len)) {
524 ("Could not read location expression DW_AT_data_member_location in DW_TAG_member %s of type <%"
525 PRIx64 ">%s", MC_dwarf_attr_integrate_string(child, DW_AT_name),
526 (uint64_t) type->id, type->name);
528 if (len == 1 && expr[0].atom == DW_OP_plus_uconst) {
529 member->offset = expr[0].number;
531 mc_dwarf_expression_init(&member->location, len, expr);
535 case MC_DW_CLASS_CONSTANT:
536 // Offset from the base address of the object:
539 if (!dwarf_formudata(&attr, &offset))
540 member->offset = offset;
542 xbt_die("Cannot get %s location <%" PRIx64 ">%s",
543 MC_dwarf_attr_integrate_string(child, DW_AT_name),
544 (uint64_t) type->id, type->name);
547 case MC_DW_CLASS_LOCLISTPTR:
548 // Reference to a location list:
550 case MC_DW_CLASS_REFERENCE:
551 // It's supposed to be possible in DWARF2 but I couldn't find its semantic
554 xbt_die("Can't handle form class (%i) / form 0x%x as DW_AT_member_location",
560 static void dw_type_free_voidp(void *t)
562 delete *(dw_type_t*)t;
565 /** \brief Populate the list of members of a type
567 * \param info ELF object containing the type DIE
568 * \param die DIE of the type
569 * \param unit DIE of the compilation unit containing the type DIE
570 * \param type the type
572 static void MC_dwarf_add_members(mc_object_info_t info, Dwarf_Die * die,
573 Dwarf_Die * unit, dw_type_t type)
577 xbt_assert(!type->members);
579 xbt_dynar_new(sizeof(dw_type_t), (void (*)(void *)) dw_type_free_voidp);
580 for (res = dwarf_child(die, &child); res == 0;
581 res = dwarf_siblingof(&child, &child)) {
582 int tag = dwarf_tag(&child);
583 if (tag == DW_TAG_member || tag == DW_TAG_inheritance) {
585 // Skip declarations:
586 if (MC_dwarf_attr_flag(&child, DW_AT_declaration, false))
589 // Skip compile time constants:
590 if (dwarf_hasattr(&child, DW_AT_const_value))
593 // TODO, we should use another type (because is is not a type but a member)
594 dw_type_t member = xbt_new0(s_dw_type_t, 1);
598 member->id = dwarf_dieoffset(&child);
600 const char *name = MC_dwarf_attr_integrate_string(&child, DW_AT_name);
602 member->name = xbt_strdup(name);
607 MC_dwarf_attr_integrate_uint(&child, DW_AT_byte_size, 0);
608 member->element_count = -1;
609 member->dw_type_id = MC_dwarf_at_type(&child);
610 member->members = NULL;
611 member->is_pointer_type = 0;
614 if (dwarf_hasattr(&child, DW_AT_data_bit_offset)) {
615 xbt_die("Can't groke DW_AT_data_bit_offset.");
618 MC_dwarf_fill_member_location(type, member, &child);
620 if (!member->dw_type_id) {
621 xbt_die("Missing type for member %s of <%" PRIx64 ">%s", member->name,
622 (uint64_t) type->id, type->name);
625 xbt_dynar_push(type->members, &member);
630 /** \brief Create a MC type object from a DIE
632 * \param info current object info object
633 * \param DIE (for a given type);
634 * \param unit compilation unit of the current DIE
635 * \return MC representation of the type
637 static dw_type_t MC_dwarf_die_to_type(mc_object_info_t info, Dwarf_Die * die,
638 Dwarf_Die * unit, dw_frame_t frame,
642 dw_type_t type = new s_dw_type();
647 type->element_count = -1;
648 type->dw_type_id = NULL;
649 type->members = NULL;
650 type->is_pointer_type = 0;
653 type->type = dwarf_tag(die);
656 type->id = dwarf_dieoffset(die);
658 const char *prefix = "";
659 switch (type->type) {
660 case DW_TAG_structure_type:
663 case DW_TAG_union_type:
666 case DW_TAG_class_type:
673 const char *name = MC_dwarf_attr_integrate_string(die, DW_AT_name);
676 ns ? bprintf("%s%s::%s", prefix, ns,
677 name) : bprintf("%s%s", prefix, name);
680 type->dw_type_id = MC_dwarf_at_type(die);
682 // Some compilers do not emit DW_AT_byte_size for pointer_type,
683 // so we fill this. We currently assume that the model-checked process is in
684 // the same architecture..
685 if (type->type == DW_TAG_pointer_type)
686 type->byte_size = sizeof(void*);
688 // Computation of the byte_size;
689 if (dwarf_hasattr_integrate(die, DW_AT_byte_size))
690 type->byte_size = MC_dwarf_attr_integrate_uint(die, DW_AT_byte_size, 0);
691 else if (type->type == DW_TAG_array_type
692 || type->type == DW_TAG_structure_type
693 || type->type == DW_TAG_class_type) {
695 if (dwarf_aggregate_size(die, &size) == 0) {
696 type->byte_size = size;
700 switch (type->type) {
701 case DW_TAG_array_type:
702 type->element_count = MC_dwarf_array_element_count(die, unit);
703 // TODO, handle DW_byte_stride and (not) DW_bit_stride
706 case DW_TAG_pointer_type:
707 case DW_TAG_reference_type:
708 case DW_TAG_rvalue_reference_type:
709 type->is_pointer_type = 1;
712 case DW_TAG_structure_type:
713 case DW_TAG_union_type:
714 case DW_TAG_class_type:
715 MC_dwarf_add_members(info, die, unit, type);
716 char *new_ns = ns == NULL ? xbt_strdup(type->name)
717 : bprintf("%s::%s", ns, name);
718 MC_dwarf_handle_children(info, die, unit, frame, new_ns);
726 static void MC_dwarf_handle_type_die(mc_object_info_t info, Dwarf_Die * die,
727 Dwarf_Die * unit, dw_frame_t frame,
730 dw_type_t type = MC_dwarf_die_to_type(info, die, unit, frame, ns);
732 char *key = bprintf("%" PRIx64, (uint64_t) type->id);
733 xbt_dict_set(info->types, key, type, NULL);
736 if (type->name && type->byte_size != 0) {
737 xbt_dict_set(info->full_types_by_name, type->name, type, NULL);
741 static int mc_anonymous_variable_index = 0;
743 static dw_variable_t MC_die_to_variable(mc_object_info_t info, Dwarf_Die * die,
744 Dwarf_Die * unit, dw_frame_t frame,
747 // Skip declarations:
748 if (MC_dwarf_attr_flag(die, DW_AT_declaration, false))
751 // Skip compile time constants:
752 if (dwarf_hasattr(die, DW_AT_const_value))
755 Dwarf_Attribute attr_location;
756 if (dwarf_attr(die, DW_AT_location, &attr_location) == NULL) {
757 // No location: do not add it ?
761 dw_variable_t variable = xbt_new0(s_dw_variable_t, 1);
762 variable->dwarf_offset = dwarf_dieoffset(die);
763 variable->global = frame == NULL; // Can be override base on DW_AT_location
764 variable->object_info = info;
766 const char *name = MC_dwarf_attr_integrate_string(die, DW_AT_name);
767 variable->name = xbt_strdup(name);
769 variable->type_origin = MC_dwarf_at_type(die);
771 int form = dwarf_whatform(&attr_location);
774 DW_FORM_sec_offset ? MC_DW_CLASS_CONSTANT : MC_dwarf_form_get_class(form);
776 case MC_DW_CLASS_EXPRLOC:
777 case MC_DW_CLASS_BLOCK:
778 // Location expression:
782 if (dwarf_getlocation(&attr_location, &expr, &len)) {
784 ("Could not read location expression in DW_AT_location of variable <%"
785 PRIx64 ">%s", (uint64_t) variable->dwarf_offset, variable->name);
788 if (len == 1 && expr[0].atom == DW_OP_addr) {
789 variable->global = 1;
790 uintptr_t offset = (uintptr_t) expr[0].number;
791 uintptr_t base = (uintptr_t) MC_object_base_address(info);
792 variable->address = (void *) (base + offset);
794 mc_dwarf_location_list_init_from_expression(&variable->locations, len,
800 case MC_DW_CLASS_LOCLISTPTR:
801 case MC_DW_CLASS_CONSTANT:
802 // Reference to location list:
803 mc_dwarf_location_list_init(&variable->locations, info, die,
807 xbt_die("Unexpected form 0x%x (%i), class 0x%x (%i) list for location in <%"
808 PRIx64 ">%s", form, form, klass, klass,
809 (uint64_t) variable->dwarf_offset, variable->name);
812 // Handle start_scope:
813 if (dwarf_hasattr(die, DW_AT_start_scope)) {
814 Dwarf_Attribute attr;
815 dwarf_attr(die, DW_AT_start_scope, &attr);
816 int form = dwarf_whatform(&attr);
817 int klass = MC_dwarf_form_get_class(form);
819 case MC_DW_CLASS_CONSTANT:
822 variable->start_scope =
823 dwarf_formudata(&attr, &value) == 0 ? (size_t) value : 0;
826 case MC_DW_CLASS_RANGELISTPTR: // TODO
829 ("Unhandled form 0x%x, class 0x%X for DW_AT_start_scope of variable %s",
830 form, klass, name == NULL ? "?" : name);
834 if (ns && variable->global) {
835 char *old_name = variable->name;
836 variable->name = bprintf("%s::%s", ns, old_name);
839 // The current code needs a variable name,
840 // generate a fake one:
841 if (!variable->name) {
842 variable->name = bprintf("@anonymous#%i", mc_anonymous_variable_index++);
848 static void MC_dwarf_handle_variable_die(mc_object_info_t info, Dwarf_Die * die,
849 Dwarf_Die * unit, dw_frame_t frame,
852 dw_variable_t variable =
853 MC_die_to_variable(info, die, unit, frame, ns);
854 if (variable == NULL)
856 MC_dwarf_register_variable(info, frame, variable);
859 static void mc_frame_free_voipd(dw_frame_t * p)
865 static void MC_dwarf_handle_scope_die(mc_object_info_t info, Dwarf_Die * die,
866 Dwarf_Die * unit, dw_frame_t parent_frame,
869 // TODO, handle DW_TAG_type/DW_TAG_location for DW_TAG_with_stmt
870 int tag = dwarf_tag(die);
871 mc_tag_class klass = MC_dwarf_tag_classify(tag);
873 // (Template) Subprogram declaration:
874 if (klass == mc_tag_subprogram
875 && MC_dwarf_attr_flag(die, DW_AT_declaration, false))
878 if (klass == mc_tag_scope)
879 xbt_assert(parent_frame, "No parent scope for this scope");
881 dw_frame_t frame = xbt_new0(s_dw_frame_t, 1);
884 frame->id = dwarf_dieoffset(die);
885 frame->object_info = info;
887 if (klass == mc_tag_subprogram) {
888 const char *name = MC_dwarf_attr_integrate_string(die, DW_AT_name);
890 ns ? bprintf("%s::%s", ns, name) : xbt_strdup(name);
893 frame->abstract_origin_id =
894 MC_dwarf_attr_dieoffset(die, DW_AT_abstract_origin);
896 // This is the base address for DWARF addresses.
897 // Relocated addresses are offset from this base address.
898 // See DWARF4 spec 7.5
899 void *base = MC_object_base_address(info);
901 // Variables are filled in the (recursive) call of MC_dwarf_handle_children:
903 xbt_dynar_new(sizeof(dw_variable_t), dw_variable_free_voidp);
905 // TODO, support DW_AT_ranges
906 uint64_t low_pc = MC_dwarf_attr_integrate_addr(die, DW_AT_low_pc);
907 frame->low_pc = low_pc ? ((char *) base) + low_pc : 0;
910 Dwarf_Attribute attr;
911 if (!dwarf_attr_integrate(die, DW_AT_high_pc, &attr)) {
912 xbt_die("Missing DW_AT_high_pc matching with DW_AT_low_pc");
918 switch (MC_dwarf_form_get_class(dwarf_whatform(&attr))) {
920 // DW_AT_high_pc if an offset from the low_pc:
921 case MC_DW_CLASS_CONSTANT:
923 if (dwarf_formsdata(&attr, &offset) != 0)
924 xbt_die("Could not read constant");
925 frame->high_pc = (void *) ((char *) frame->low_pc + offset);
928 // DW_AT_high_pc is a relocatable address:
929 case MC_DW_CLASS_ADDRESS:
930 if (dwarf_formaddr(&attr, &high_pc) != 0)
931 xbt_die("Could not read address");
932 frame->high_pc = ((char *) base) + high_pc;
936 xbt_die("Unexpected class for DW_AT_high_pc");
941 if (klass == mc_tag_subprogram) {
942 Dwarf_Attribute attr_frame_base;
943 if (dwarf_attr_integrate(die, DW_AT_frame_base, &attr_frame_base))
944 mc_dwarf_location_list_init(&frame->frame_base, info, die,
949 xbt_dynar_new(sizeof(dw_frame_t), (void_f_pvoid_t) mc_frame_free_voipd);
952 if (klass == mc_tag_subprogram) {
953 char *key = bprintf("%" PRIx64, (uint64_t) frame->id);
954 xbt_dict_set(info->subprograms, key, frame, NULL);
956 } else if (klass == mc_tag_scope) {
957 xbt_dynar_push(parent_frame->scopes, &frame);
960 MC_dwarf_handle_children(info, die, unit, frame, ns);
963 static void mc_dwarf_handle_namespace_die(mc_object_info_t info,
964 Dwarf_Die * die, Dwarf_Die * unit,
968 const char *name = MC_dwarf_attr_integrate_string(die, DW_AT_name);
970 xbt_die("Unexpected namespace in a subprogram");
971 char *new_ns = ns == NULL ? xbt_strdup(name)
972 : bprintf("%s::%s", ns, name);
973 MC_dwarf_handle_children(info, die, unit, frame, new_ns);
977 static void MC_dwarf_handle_children(mc_object_info_t info, Dwarf_Die * die,
978 Dwarf_Die * unit, dw_frame_t frame,
981 // For each child DIE:
984 for (res = dwarf_child(die, &child); res == 0;
985 res = dwarf_siblingof(&child, &child)) {
986 MC_dwarf_handle_die(info, &child, unit, frame, ns);
990 static void MC_dwarf_handle_die(mc_object_info_t info, Dwarf_Die * die,
991 Dwarf_Die * unit, dw_frame_t frame,
994 int tag = dwarf_tag(die);
995 mc_tag_class klass = MC_dwarf_tag_classify(tag);
1000 MC_dwarf_handle_type_die(info, die, unit, frame, ns);
1003 // Subprogram or scope:
1004 case mc_tag_subprogram:
1006 MC_dwarf_handle_scope_die(info, die, unit, frame, ns);
1010 case mc_tag_variable:
1011 MC_dwarf_handle_variable_die(info, die, unit, frame, ns);
1014 case mc_tag_namespace:
1015 mc_dwarf_handle_namespace_die(info, die, unit, frame, ns);
1024 /** \brief Populate the debugging informations of the given ELF object
1026 * Read the DWARf information of the EFFL object and populate the
1027 * lists of types, variables, functions.
1029 void MC_dwarf_get_variables(mc_object_info_t info)
1031 int fd = open(info->file_name, O_RDONLY);
1033 xbt_die("Could not open file %s", info->file_name);
1035 Dwarf *dwarf = dwarf_begin(fd, DWARF_C_READ);
1036 if (dwarf == NULL) {
1037 xbt_die("Your program must be compiled with -g (%s)", info->file_name);
1039 // For each compilation unit:
1040 Dwarf_Off offset = 0;
1041 Dwarf_Off next_offset = 0;
1043 while (dwarf_nextcu(dwarf, offset, &next_offset, &length, NULL, NULL, NULL) ==
1046 if (dwarf_offdie(dwarf, offset + length, &unit_die) != NULL) {
1048 // For each child DIE:
1051 for (res = dwarf_child(&unit_die, &child); res == 0;
1052 res = dwarf_siblingof(&child, &child)) {
1053 MC_dwarf_handle_die(info, &child, &unit_die, NULL, NULL);
1057 offset = next_offset;
1064 /************************** Free functions *************************/
1066 void mc_frame_free(dw_frame_t frame)
1068 xbt_free(frame->name);
1069 mc_dwarf_location_list_clear(&(frame->frame_base));
1070 xbt_dynar_free(&(frame->variables));
1071 xbt_dynar_free(&(frame->scopes));
1075 s_dw_type::s_dw_type()
1079 s_dw_type::~s_dw_type()
1081 xbt_free(this->name);
1082 xbt_free(this->dw_type_id);
1083 xbt_dynar_free(&this->members);
1084 mc_dwarf_expression_clear(&this->location);
1087 static void dw_type_free(dw_type_t t)
1092 void dw_variable_free(dw_variable_t v)
1096 xbt_free(v->type_origin);
1098 if (v->locations.locations)
1099 mc_dwarf_location_list_clear(&v->locations);
1104 void dw_variable_free_voidp(void *t)
1106 dw_variable_free((dw_variable_t) * (void **) t);
1109 // ***** object_info
1111 s_mc_object_info::s_mc_object_info()
1113 this->types = xbt_dict_new_homogeneous((void (*)(void *)) dw_type_free);
1114 this->subprograms = xbt_dict_new_homogeneous((void (*)(void *)) mc_frame_free);
1115 this->global_variables =
1116 xbt_dynar_new(sizeof(dw_variable_t), dw_variable_free_voidp);
1118 this->full_types_by_name = xbt_dict_new_homogeneous(NULL);
1121 s_mc_object_info::~s_mc_object_info()
1123 xbt_free(this->file_name);
1124 xbt_dict_free(&this->subprograms);
1125 xbt_dynar_free(&this->global_variables);
1126 xbt_dict_free(&this->types);
1127 xbt_dict_free(&this->full_types_by_name);
1128 xbt_dynar_free(&this->functions_index);
1133 void *MC_object_base_address(mc_object_info_t info)
1135 if (info->flags & MC_OBJECT_INFO_EXECUTABLE)
1137 void *result = info->start_exec;
1138 if (info->start_rw != NULL && result > (void *) info->start_rw)
1139 result = info->start_rw;
1140 if (info->start_ro != NULL && result > (void *) info->start_ro)
1141 result = info->start_ro;
1145 // ***** Functions index
1147 static int MC_compare_frame_index_items(mc_function_index_item_t a,
1148 mc_function_index_item_t b)
1150 if (a->low_pc < b->low_pc)
1152 else if (a->low_pc == b->low_pc)
1158 static void MC_make_functions_index(mc_object_info_t info)
1160 xbt_dynar_t index = xbt_dynar_new(sizeof(s_mc_function_index_item_t), NULL);
1162 // Populate the array:
1163 dw_frame_t frame = NULL;
1164 xbt_dict_cursor_t cursor;
1166 xbt_dict_foreach(info->subprograms, cursor, key, frame) {
1167 if (frame->low_pc == NULL)
1169 s_mc_function_index_item_t entry;
1170 entry.low_pc = frame->low_pc;
1171 entry.high_pc = frame->high_pc;
1172 entry.function = frame;
1173 xbt_dynar_push(index, &entry);
1176 mc_function_index_item_t base =
1177 (mc_function_index_item_t) xbt_dynar_get_ptr(index, 0);
1179 // Sort the array by low_pc:
1181 xbt_dynar_length(index),
1182 sizeof(s_mc_function_index_item_t),
1183 (int (*)(const void *, const void *)) MC_compare_frame_index_items);
1185 info->functions_index = index;
1188 static void MC_post_process_variables(mc_object_info_t info)
1190 unsigned cursor = 0;
1191 dw_variable_t variable = NULL;
1192 xbt_dynar_foreach(info->global_variables, cursor, variable) {
1193 if (variable->type_origin) {
1194 variable->type = (dw_type_t) xbt_dict_get_or_null(info->types, variable->type_origin);
1199 static void mc_post_process_scope(mc_object_info_t info, dw_frame_t scope)
1202 if (scope->tag == DW_TAG_inlined_subroutine) {
1204 // Attach correct namespaced name in inlined subroutine:
1205 char *key = bprintf("%" PRIx64, (uint64_t) scope->abstract_origin_id);
1206 dw_frame_t abstract_origin = (dw_frame_t) xbt_dict_get_or_null(info->subprograms, key);
1207 xbt_assert(abstract_origin, "Could not lookup abstract origin %s", key);
1209 scope->name = xbt_strdup(abstract_origin->name);
1213 unsigned cursor = 0;
1214 dw_variable_t variable = NULL;
1215 xbt_dynar_foreach(scope->variables, cursor, variable) {
1216 if (variable->type_origin) {
1217 variable->type = (dw_type_t) xbt_dict_get_or_null(info->types, variable->type_origin);
1221 // Recursive post-processing of nested-scopes:
1222 dw_frame_t nested_scope = NULL;
1223 xbt_dynar_foreach(scope->scopes, cursor, nested_scope)
1224 mc_post_process_scope(info, nested_scope);
1228 static void MC_post_process_functions(mc_object_info_t info)
1230 xbt_dict_cursor_t cursor;
1232 dw_frame_t subprogram = NULL;
1233 xbt_dict_foreach(info->subprograms, cursor, key, subprogram) {
1234 mc_post_process_scope(info, subprogram);
1239 /** \brief Fill/lookup the "subtype" field.
1241 static void MC_resolve_subtype(mc_object_info_t info, dw_type_t type)
1244 if (type->dw_type_id == NULL)
1246 type->subtype = (dw_type_t) xbt_dict_get_or_null(info->types, type->dw_type_id);
1247 if (type->subtype == NULL)
1249 if (type->subtype->byte_size != 0)
1251 if (type->subtype->name == NULL)
1253 // Try to find a more complete description of the type:
1254 // We need to fix in order to support C++.
1257 (dw_type_t) xbt_dict_get_or_null(info->full_types_by_name, type->subtype->name);
1258 if (subtype != NULL) {
1259 type->subtype = subtype;
1264 static void MC_post_process_types(mc_object_info_t info)
1266 xbt_dict_cursor_t cursor = NULL;
1270 // Lookup "subtype" field:
1271 xbt_dict_foreach(info->types, cursor, origin, type) {
1272 MC_resolve_subtype(info, type);
1276 if (type->members != NULL)
1277 xbt_dynar_foreach(type->members, i, member) {
1278 MC_resolve_subtype(info, member);
1283 /** \brief Finds informations about a given shared object/executable */
1284 std::shared_ptr<s_mc_object_info_t> MC_find_object_info(
1285 std::vector<simgrid::mc::VmMap> const& maps, const char *name, int executable)
1287 std::shared_ptr<s_mc_object_info_t> result =
1288 std::make_shared<s_mc_object_info_t>();
1290 result->flags |= MC_OBJECT_INFO_EXECUTABLE;
1291 result->file_name = xbt_strdup(name);
1292 MC_find_object_address(maps, result.get());
1293 MC_dwarf_get_variables(result.get());
1294 MC_post_process_types(result.get());
1295 MC_post_process_variables(result.get());
1296 MC_post_process_functions(result.get());
1297 MC_make_functions_index(result.get());
1298 return std::move(result);
1301 /*************************************************************************/
1303 static int MC_dwarf_get_variable_index(xbt_dynar_t variables, char *var,
1307 if (xbt_dynar_is_empty(variables))
1310 unsigned int cursor = 0;
1312 int end = xbt_dynar_length(variables) - 1;
1313 dw_variable_t var_test = NULL;
1315 while (start <= end) {
1316 cursor = (start + end) / 2;
1318 (dw_variable_t) xbt_dynar_get_as(variables, cursor, dw_variable_t);
1319 if (strcmp(var_test->name, var) < 0) {
1321 } else if (strcmp(var_test->name, var) > 0) {
1324 if (address) { /* global variable */
1325 if (var_test->address == address)
1327 if (var_test->address > address)
1331 } else { /* local variable */
1337 if (strcmp(var_test->name, var) == 0) {
1338 if (address && var_test->address < address)
1342 } else if (strcmp(var_test->name, var) < 0)
1349 void MC_dwarf_register_global_variable(mc_object_info_t info,
1350 dw_variable_t variable)
1353 MC_dwarf_get_variable_index(info->global_variables, variable->name,
1356 xbt_dynar_insert_at(info->global_variables, index, &variable);
1360 void MC_dwarf_register_non_global_variable(mc_object_info_t info,
1362 dw_variable_t variable)
1364 xbt_assert(frame, "Frame is NULL");
1366 MC_dwarf_get_variable_index(frame->variables, variable->name, NULL);
1368 xbt_dynar_insert_at(frame->variables, index, &variable);
1372 void MC_dwarf_register_variable(mc_object_info_t info, dw_frame_t frame,
1373 dw_variable_t variable)
1375 if (variable->global)
1376 MC_dwarf_register_global_variable(info, variable);
1377 else if (frame == NULL)
1378 xbt_die("No frame for this local variable");
1380 MC_dwarf_register_non_global_variable(info, frame, variable);
1383 void MC_post_process_object_info(mc_process_t process, mc_object_info_t info)
1385 xbt_dict_cursor_t cursor = NULL;
1387 dw_type_t type = NULL;
1388 xbt_dict_foreach(info->types, cursor, key, type) {
1390 dw_type_t subtype = type;
1391 while (subtype->type == DW_TAG_typedef || subtype->type == DW_TAG_volatile_type
1392 || subtype->type == DW_TAG_const_type) {
1393 if (subtype->subtype)
1394 subtype = subtype->subtype;
1399 // Resolve full_type:
1400 if (subtype->name && subtype->byte_size == 0) {
1401 for (auto const& object_info : process->object_infos) {
1402 dw_type_t same_type = (dw_type_t)
1403 xbt_dict_get_or_null(object_info->full_types_by_name,
1405 if (same_type && same_type->name && same_type->byte_size) {
1406 type->full_type = same_type;
1410 } else type->full_type = subtype;