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. */
8 #define DW_LANG_Objc DW_LANG_ObjC /* fix spelling error in older dwarf.h */
10 #include <elfutils/libdw.h>
13 #include <simgrid_config.h>
15 #include <xbt/sysdep.h>
17 #include "mc_private.h"
19 XBT_LOG_NEW_DEFAULT_SUBCATEGORY(mc_dwarf, mc, "DWARF processing");
21 /** \brief The default DW_TAG_lower_bound for a given DW_AT_language.
23 * The default for a given language is defined in the DWARF spec.
25 * \param language consant as defined by the DWARf spec
27 static uint64_t MC_dwarf_default_lower_bound(int lang);
29 /** \brief Computes the the element_count of a DW_TAG_enumeration_type DIE
31 * This is the number of elements in a given array dimension.
33 * A reference of the compilation unit (DW_TAG_compile_unit) is
34 * needed because the default lower bound (when there is no DW_AT_lower_bound)
35 * depends of the language of the compilation unit (DW_AT_language).
37 * \param die DIE for the DW_TAG_enumeration_type or DW_TAG_subrange_type
38 * \param unit DIE of the DW_TAG_compile_unit
40 static uint64_t MC_dwarf_subrange_element_count(Dwarf_Die* die, Dwarf_Die* unit);
42 /** \brief Computes the number of elements of a given DW_TAG_array_type.
44 * \param die DIE for the DW_TAG_array_type
46 static uint64_t MC_dwarf_array_element_count(Dwarf_Die* die, Dwarf_Die* unit);
48 /** \brief Process a DIE
50 * \param info the resulting object fot the library/binary file (output)
51 * \param die the current DIE
52 * \param unit the DIE of the compile unit of the current DIE
53 * \param frame containg frame if any
55 static void MC_dwarf_handle_die(mc_object_info_t info, Dwarf_Die* die, Dwarf_Die* unit, dw_frame_t frame, const char* namespace);
57 /** \brief Process a type DIE
59 static void MC_dwarf_handle_type_die(mc_object_info_t info, Dwarf_Die* die, Dwarf_Die* unit, dw_frame_t frame, const char* namespace);
61 /** \brief Calls MC_dwarf_handle_die on all childrend of the given die
63 * \param info the resulting object fot the library/binary file (output)
64 * \param die the current DIE
65 * \param unit the DIE of the compile unit of the current DIE
66 * \param frame containg frame if any
68 static void MC_dwarf_handle_children(mc_object_info_t info, Dwarf_Die* die, Dwarf_Die* unit, dw_frame_t frame, const char* namespace);
70 /** \brief Handle a variable (DW_TAG_variable or other)
72 * \param info the resulting object fot the library/binary file (output)
73 * \param die the current DIE
74 * \param unit the DIE of the compile unit of the current DIE
75 * \param frame containg frame if any
77 static void MC_dwarf_handle_variable_die(mc_object_info_t info, Dwarf_Die* die, Dwarf_Die* unit, dw_frame_t frame, const char* namespace);
79 /** \brief Get the DW_TAG_type of the DIE
82 * \return DW_TAG_type attribute as a new string (NULL if none)
84 static char* MC_dwarf_at_type(Dwarf_Die* die);
86 /** \brief Get the name of an attribute (DW_AT_*) from its code
88 * \param attr attribute code (see the DWARF specification)
89 * \return name of the attribute
91 const char* MC_dwarf_attrname(int attr) {
93 #include "mc_dwarf_attrnames.h"
95 return "DW_AT_unknown";
99 /** \brief Get the name of a dwarf tag (DW_TAG_*) from its code
101 * \param tag tag code (see the DWARF specification)
102 * \return name of the tag
104 const char* MC_dwarf_tagname(int tag) {
106 #include "mc_dwarf_tagnames.h"
108 return "DW_TAG_invalid";
110 return "DW_TAG_unknown";
114 /** \brief A class of DWARF tags (DW_TAG_*)
116 typedef enum mc_tag_class {
125 static mc_tag_class MC_dwarf_tag_classify(int tag) {
128 case DW_TAG_array_type:
129 case DW_TAG_class_type:
130 case DW_TAG_enumeration_type:
132 case DW_TAG_pointer_type:
133 case DW_TAG_reference_type:
134 case DW_TAG_rvalue_reference_type:
135 case DW_TAG_string_type:
136 case DW_TAG_structure_type:
137 case DW_TAG_subroutine_type:
138 case DW_TAG_union_type:
139 case DW_TAG_ptr_to_member_type:
140 case DW_TAG_set_type:
141 case DW_TAG_subrange_type:
142 case DW_TAG_base_type:
143 case DW_TAG_const_type:
144 case DW_TAG_file_type:
145 case DW_TAG_packed_type:
146 case DW_TAG_volatile_type:
147 case DW_TAG_restrict_type:
148 case DW_TAG_interface_type:
149 case DW_TAG_unspecified_type:
150 case DW_TAG_mutable_type:
151 case DW_TAG_shared_type:
154 case DW_TAG_subprogram:
155 return mc_tag_subprogram;
157 case DW_TAG_variable:
158 case DW_TAG_formal_parameter:
159 return mc_tag_variable;
161 case DW_TAG_lexical_block:
162 case DW_TAG_try_block:
163 case DW_TAG_catch_block:
164 case DW_TAG_inlined_subroutine:
165 case DW_TAG_with_stmt:
168 case DW_TAG_namespace:
169 return mc_tag_namespace;
172 return mc_tag_unknown;
177 #define MC_DW_CLASS_UNKNOWN 0
178 #define MC_DW_CLASS_ADDRESS 1 // Location in the address space of the program
179 #define MC_DW_CLASS_BLOCK 2 // Arbitrary block of bytes
180 #define MC_DW_CLASS_CONSTANT 3
181 #define MC_DW_CLASS_STRING 3 // String
182 #define MC_DW_CLASS_FLAG 4 // Boolean
183 #define MC_DW_CLASS_REFERENCE 5 // Reference to another DIE
184 #define MC_DW_CLASS_EXPRLOC 6 // DWARF expression/location description
185 #define MC_DW_CLASS_LINEPTR 7
186 #define MC_DW_CLASS_LOCLISTPTR 8
187 #define MC_DW_CLASS_MACPTR 9
188 #define MC_DW_CLASS_RANGELISTPTR 10
190 /** \brief Find the DWARF data class for a given DWARF data form
192 * This mapping is defined in the DWARF spec.
194 * \param form The form (values taken from the DWARF spec)
195 * \return An internal representation for the corresponding class
197 static int MC_dwarf_form_get_class(int form) {
200 return MC_DW_CLASS_ADDRESS;
205 return MC_DW_CLASS_BLOCK;
212 return MC_DW_CLASS_CONSTANT;
215 return MC_DW_CLASS_STRING;
216 case DW_FORM_ref_addr:
221 case DW_FORM_ref_udata:
222 return MC_DW_CLASS_REFERENCE;
224 case DW_FORM_flag_present:
225 return MC_DW_CLASS_FLAG;
226 case DW_FORM_exprloc:
227 return MC_DW_CLASS_EXPRLOC;
231 return MC_DW_CLASS_UNKNOWN;
235 /** \brief Get the name of the tag of a given DIE
238 * \return name of the tag of this DIE
240 static inline const char* MC_dwarf_die_tagname(Dwarf_Die* die) {
241 return MC_dwarf_tagname(dwarf_tag(die));
246 /** \brief Get an attribute of a given DIE as a string
249 * \param attribute attribute
250 * \return value of the given attribute of the given DIE
252 static const char* MC_dwarf_attr_integrate_string(Dwarf_Die* die, int attribute) {
253 Dwarf_Attribute attr;
254 if (!dwarf_attr_integrate(die, attribute, &attr)) {
257 return dwarf_formstring(&attr);
261 /** \brief Get the linkage name of a DIE.
263 * Use either DW_AT_linkage_name or DW_AT_MIPS_linkage_name.
264 * DW_AT_linkage_name is standardized since DWARF 4.
265 * Before this version of DWARF, the MIPS extensions
266 * DW_AT_MIPS_linkage_name is used (at least by GCC).
269 * \return linkage name of the given DIE (or NULL)
271 static const char* MC_dwarf_at_linkage_name(Dwarf_Die* die) {
272 const char* name = MC_dwarf_attr_integrate_string(die, DW_AT_linkage_name);
274 name = MC_dwarf_attr_integrate_string(die, DW_AT_MIPS_linkage_name);
278 static Dwarf_Off MC_dwarf_attr_dieoffset(Dwarf_Die* die, int attribute) {
279 Dwarf_Attribute attr;
280 if (dwarf_hasattr_integrate(die, attribute)) {
281 dwarf_attr_integrate(die, attribute, &attr);
282 Dwarf_Die subtype_die;
283 if (dwarf_formref_die(&attr, &subtype_die)==NULL) {
284 xbt_die("Could not find DIE");
286 return dwarf_dieoffset(&subtype_die);
291 static Dwarf_Off MC_dwarf_attr_integrate_dieoffset(Dwarf_Die* die, int attribute) {
292 Dwarf_Attribute attr;
293 if (dwarf_hasattr_integrate(die, attribute)) {
294 dwarf_attr_integrate(die, DW_AT_type, &attr);
295 Dwarf_Die subtype_die;
296 if (dwarf_formref_die(&attr, &subtype_die)==NULL) {
297 xbt_die("Could not find DIE");
299 return dwarf_dieoffset(&subtype_die);
304 /** \brief Find the type/subtype (DW_AT_type) for a DIE
307 * \return DW_AT_type reference as a global offset in hexadecimal (or NULL)
309 static char* MC_dwarf_at_type(Dwarf_Die* die) {
310 Dwarf_Off offset = MC_dwarf_attr_integrate_dieoffset(die, DW_AT_type);
311 return offset == 0 ? NULL : bprintf("%" PRIx64 , offset);
314 static uint64_t MC_dwarf_attr_integrate_addr(Dwarf_Die* die, int attribute) {
315 Dwarf_Attribute attr;
316 if(dwarf_attr_integrate(die, attribute, &attr)==NULL)
319 if (dwarf_formaddr(&attr, &value) == 0)
320 return (uint64_t) value;
325 static uint64_t MC_dwarf_attr_integrate_uint(Dwarf_Die* die, int attribute, uint64_t default_value) {
326 Dwarf_Attribute attr;
327 if (dwarf_attr_integrate(die, attribute, &attr)==NULL)
328 return default_value;
330 return dwarf_formudata(dwarf_attr_integrate(die, attribute, &attr), &value) == 0 ? (uint64_t) value : default_value;
333 static bool MC_dwarf_attr_flag(Dwarf_Die* die, int attribute, bool integrate) {
334 Dwarf_Attribute attr;
335 if ((integrate ? dwarf_attr_integrate(die, attribute, &attr)
336 : dwarf_attr(die, attribute, &attr))==0)
340 if (dwarf_formflag(&attr, &result))
341 xbt_die("Unexpected form for attribute %s",
342 MC_dwarf_attrname(attribute));
346 /** \brief Find the default lower bound for a given language
348 * The default lower bound of an array (when DW_TAG_lower_bound
349 * is missing) depends on the language of the compilation unit.
351 * \param lang Language of the compilation unit (values defined in the DWARF spec)
352 * \return Default lower bound of an array in this compilation unit
354 static uint64_t MC_dwarf_default_lower_bound(int lang) {
359 case DW_LANG_C_plus_plus:
363 case DW_LANG_ObjC_plus_plus:
369 case DW_LANG_Fortran77:
370 case DW_LANG_Fortran90:
371 case DW_LANG_Fortran95:
372 case DW_LANG_Modula2:
373 case DW_LANG_Pascal83:
375 case DW_LANG_Cobol74:
376 case DW_LANG_Cobol85:
379 xbt_die("No default DW_TAG_lower_bound for language %i and none given", lang);
384 /** \brief Finds the number of elements in a DW_TAG_subrange_type or DW_TAG_enumeration_type DIE
387 * \param unit DIE of the compilation unit
388 * \return number of elements in the range
390 static uint64_t MC_dwarf_subrange_element_count(Dwarf_Die* die, Dwarf_Die* unit) {
391 xbt_assert(dwarf_tag(die)==DW_TAG_enumeration_type ||dwarf_tag(die)==DW_TAG_subrange_type,
392 "MC_dwarf_subrange_element_count called with DIE of type %s", MC_dwarf_die_tagname(die));
394 // Use DW_TAG_count if present:
395 if (dwarf_hasattr_integrate(die, DW_AT_count)) {
396 return MC_dwarf_attr_integrate_uint(die, DW_AT_count, 0);
399 // Otherwise compute DW_TAG_upper_bound-DW_TAG_lower_bound + 1:
401 if (!dwarf_hasattr_integrate(die, DW_AT_upper_bound)) {
402 // This is not really 0, but the code expects this (we do not know):
405 uint64_t upper_bound = MC_dwarf_attr_integrate_uint(die, DW_AT_upper_bound, -1);
407 uint64_t lower_bound = 0;
408 if (dwarf_hasattr_integrate(die, DW_AT_lower_bound)) {
409 lower_bound = MC_dwarf_attr_integrate_uint(die, DW_AT_lower_bound, -1);
411 lower_bound = MC_dwarf_default_lower_bound(dwarf_srclang(unit));
413 return upper_bound - lower_bound + 1;
416 /** \brief Finds the number of elements in a array type (DW_TAG_array_type)
418 * The compilation unit might be needed because the default lower
419 * bound depends on the language of the compilation unit.
421 * \param die the DIE of the DW_TAG_array_type
422 * \param unit the DIE of the compilation unit
423 * \return number of elements in this array type
425 static uint64_t MC_dwarf_array_element_count(Dwarf_Die* die, Dwarf_Die* unit) {
426 xbt_assert(dwarf_tag(die)==DW_TAG_array_type,
427 "MC_dwarf_array_element_count called with DIE of type %s", MC_dwarf_die_tagname(die));
432 for (res=dwarf_child(die, &child); res==0; res=dwarf_siblingof(&child,&child)) {
433 int child_tag = dwarf_tag(&child);
434 if (child_tag==DW_TAG_subrange_type ||child_tag==DW_TAG_enumeration_type) {
435 result *= MC_dwarf_subrange_element_count(&child, unit);
443 /** \brief Initialize the location of a member of a type
444 * (DW_AT_data_member_location of a DW_TAG_member).
446 * \param type a type (struct, class)
447 * \param member the member of the type
448 * \param child DIE of the member (DW_TAG_member)
450 static void MC_dwarf_fill_member_location(dw_type_t type, dw_type_t member, Dwarf_Die* child) {
451 if (dwarf_hasattr(child, DW_AT_data_bit_offset)) {
452 xbt_die("Can't groke DW_AT_data_bit_offset.");
455 if (!dwarf_hasattr_integrate(child, DW_AT_data_member_location)) {
456 if (type->type != DW_TAG_union_type) {
458 "Missing DW_AT_data_member_location field in DW_TAG_member %s of type <%"PRIx64">%s",
459 member->name, (uint64_t) type->id, type->name);
465 Dwarf_Attribute attr;
466 dwarf_attr_integrate(child, DW_AT_data_member_location, &attr);
467 int form = dwarf_whatform(&attr);
468 int klass = MC_dwarf_form_get_class(form);
470 case MC_DW_CLASS_EXPRLOC:
471 case MC_DW_CLASS_BLOCK:
472 // Location expression:
476 if (dwarf_getlocation(&attr, &expr, &len)) {
478 "Could not read location expression DW_AT_data_member_location in DW_TAG_member %s of type <%"PRIx64">%s",
479 MC_dwarf_attr_integrate_string(child, DW_AT_name),
480 (uint64_t) type->id, type->name);
482 if (len==1 && expr[0].atom == DW_OP_plus_uconst) {
483 member->offset = expr[0].number;
485 mc_dwarf_expression_init(&member->location, len, expr);
489 case MC_DW_CLASS_CONSTANT:
490 // Offset from the base address of the object:
493 if (!dwarf_formudata(&attr, &offset))
494 member->offset = offset;
496 xbt_die("Cannot get %s location <%"PRIx64">%s",
497 MC_dwarf_attr_integrate_string(child, DW_AT_name),
498 (uint64_t) type->id, type->name);
501 case MC_DW_CLASS_LOCLISTPTR:
502 // Reference to a location list:
504 case MC_DW_CLASS_REFERENCE:
505 // It's supposed to be possible in DWARF2 but I couldn't find its semantic
509 "Can't handle form class (%i) / form 0x%x as DW_AT_member_location",
515 static void dw_type_free_voidp(void *t){
516 dw_type_free((dw_type_t) * (void **) t);
519 /** \brief Populate the list of members of a type
521 * \param info ELF object containing the type DIE
522 * \param die DIE of the type
523 * \param unit DIE of the compilation unit containing the type DIE
524 * \param type the type
526 static void MC_dwarf_add_members(mc_object_info_t info, Dwarf_Die* die, Dwarf_Die* unit, dw_type_t type) {
529 xbt_assert(!type->members);
530 type->members = xbt_dynar_new(sizeof(dw_type_t), (void(*)(void*))dw_type_free_voidp);
531 for (res=dwarf_child(die, &child); res==0; res=dwarf_siblingof(&child,&child)) {
532 int tag = dwarf_tag(&child);
533 if (tag==DW_TAG_member || tag==DW_TAG_inheritance) {
535 // Skip declarations:
536 if (MC_dwarf_attr_flag(&child, DW_AT_declaration, false))
539 // Skip compile time constants:
540 if(dwarf_hasattr(&child, DW_AT_const_value))
543 // TODO, we should use another type (because is is not a type but a member)
544 dw_type_t member = xbt_new0(s_dw_type_t, 1);
548 member->id = dwarf_dieoffset(&child);
550 const char* name = MC_dwarf_attr_integrate_string(&child, DW_AT_name);
552 member->name = xbt_strdup(name);
556 member->byte_size = MC_dwarf_attr_integrate_uint(&child, DW_AT_byte_size, 0);
557 member->element_count = -1;
558 member->dw_type_id = MC_dwarf_at_type(&child);
559 member->members = NULL;
560 member->is_pointer_type = 0;
563 if(dwarf_hasattr(&child, DW_AT_data_bit_offset)) {
564 xbt_die("Can't groke DW_AT_data_bit_offset.");
567 MC_dwarf_fill_member_location(type, member, &child);
569 if (!member->dw_type_id) {
570 xbt_die("Missing type for member %s of <%"PRIx64">%s", member->name, (uint64_t) type->id, type->name);
573 xbt_dynar_push(type->members, &member);
578 /** \brief Create a MC type object from a DIE
580 * \param info current object info object
581 * \param DIE (for a given type);
582 * \param unit compilation unit of the current DIE
583 * \return MC representation of the type
585 static dw_type_t MC_dwarf_die_to_type(mc_object_info_t info, Dwarf_Die* die, Dwarf_Die* unit, dw_frame_t frame, const char* namespace) {
587 dw_type_t type = xbt_new0(s_dw_type_t, 1);
592 type->element_count = -1;
593 type->dw_type_id = NULL;
594 type->members = NULL;
595 type->is_pointer_type = 0;
598 type->type = dwarf_tag(die);
601 type->id = dwarf_dieoffset(die);
603 const char* prefix = "";
604 switch (type->type) {
605 case DW_TAG_structure_type:
608 case DW_TAG_union_type:
611 case DW_TAG_class_type:
618 const char* name = MC_dwarf_attr_integrate_string(die, DW_AT_name);
620 type->name = namespace ? bprintf("%s%s::%s", prefix, namespace, name) : bprintf("%s%s", prefix, name);
623 type->dw_type_id = MC_dwarf_at_type(die);
625 // Computation of the byte_size;
626 if (dwarf_hasattr_integrate(die, DW_AT_byte_size))
627 type->byte_size = MC_dwarf_attr_integrate_uint(die, DW_AT_byte_size, 0);
628 else if (type->type == DW_TAG_array_type || type->type==DW_TAG_structure_type || type->type==DW_TAG_class_type) {
630 if (dwarf_aggregate_size(die, &size)==0) {
631 type->byte_size = size;
635 switch (type->type) {
636 case DW_TAG_array_type:
637 type->element_count = MC_dwarf_array_element_count(die, unit);
638 // TODO, handle DW_byte_stride and (not) DW_bit_stride
641 case DW_TAG_pointer_type:
642 case DW_TAG_reference_type:
643 case DW_TAG_rvalue_reference_type:
644 type->is_pointer_type = 1;
647 case DW_TAG_structure_type:
648 case DW_TAG_union_type:
649 case DW_TAG_class_type:
650 MC_dwarf_add_members(info, die, unit, type);
651 char* new_namespace = namespace == NULL ? xbt_strdup(type->name)
652 : bprintf("%s::%s", namespace, name);
653 MC_dwarf_handle_children(info, die, unit, frame, new_namespace);
661 static void MC_dwarf_handle_type_die(mc_object_info_t info, Dwarf_Die* die, Dwarf_Die* unit, dw_frame_t frame, const char* namespace) {
662 dw_type_t type = MC_dwarf_die_to_type(info, die, unit, frame, namespace);
664 char* key = bprintf("%" PRIx64, (uint64_t) type->id);
665 xbt_dict_set(info->types, key, type, NULL);
668 if(type->name && type->byte_size!=0) {
669 xbt_dict_set(info->full_types_by_name, type->name, type, NULL);
673 static int mc_anonymous_variable_index = 0;
675 static dw_variable_t MC_die_to_variable(mc_object_info_t info, Dwarf_Die* die, Dwarf_Die* unit, dw_frame_t frame, const char* namespace) {
676 // Skip declarations:
677 if (MC_dwarf_attr_flag(die, DW_AT_declaration, false))
680 // Skip compile time constants:
681 if(dwarf_hasattr(die, DW_AT_const_value))
684 Dwarf_Attribute attr_location;
685 if (dwarf_attr(die, DW_AT_location, &attr_location)==NULL) {
686 // No location: do not add it ?
690 dw_variable_t variable = xbt_new0(s_dw_variable_t, 1);
691 variable->dwarf_offset = dwarf_dieoffset(die);
692 variable->global = frame == NULL; // Can be override base on DW_AT_location
693 variable->object_info = info;
695 const char* name = MC_dwarf_attr_integrate_string(die, DW_AT_name);
696 variable->name = xbt_strdup(name);
698 variable->type_origin = MC_dwarf_at_type(die);
700 int form = dwarf_whatform(&attr_location);
701 int klass = form == DW_FORM_sec_offset ? MC_DW_CLASS_CONSTANT : MC_dwarf_form_get_class(form);
703 case MC_DW_CLASS_EXPRLOC:
704 case MC_DW_CLASS_BLOCK:
705 // Location expression:
709 if (dwarf_getlocation(&attr_location, &expr, &len)) {
711 "Could not read location expression in DW_AT_location of variable <%"PRIx64">%s",
712 (uint64_t) variable->dwarf_offset, variable->name);
715 if (len==1 && expr[0].atom == DW_OP_addr) {
716 variable->global = 1;
717 uintptr_t offset = (uintptr_t) expr[0].number;
718 uintptr_t base = (uintptr_t) MC_object_base_address(info);
719 variable->address = (void*) (base + offset);
721 mc_dwarf_location_list_init_from_expression(&variable->locations, len, expr);
726 case MC_DW_CLASS_LOCLISTPTR:
727 case MC_DW_CLASS_CONSTANT:
728 // Reference to location list:
729 mc_dwarf_location_list_init(&variable->locations, info, die, &attr_location);
732 xbt_die("Unexpected form 0x%x (%i), class 0x%x (%i) list for location in <%"PRIx64">%s",
733 form, form, klass, klass, (uint64_t) variable->dwarf_offset, variable->name);
736 // Handle start_scope:
737 if (dwarf_hasattr(die, DW_AT_start_scope)) {
738 Dwarf_Attribute attr;
739 dwarf_attr(die, DW_AT_start_scope, &attr);
740 int form = dwarf_whatform(&attr);
741 int klass = MC_dwarf_form_get_class(form);
743 case MC_DW_CLASS_CONSTANT:
746 variable->start_scope = dwarf_formudata(&attr, &value) == 0 ? (size_t) value : 0;
749 case MC_DW_CLASS_RANGELISTPTR: // TODO
751 xbt_die("Unhandled form 0x%x, class 0x%X for DW_AT_start_scope of variable %s",
752 form, klass, name==NULL ? "?" : name);
756 if(namespace && variable->global) {
757 char* old_name = variable->name;
758 variable->name = bprintf("%s::%s", namespace, old_name);
762 // The current code needs a variable name,
763 // generate a fake one:
764 if(!variable->name) {
765 variable->name = bprintf("@anonymous#%i", mc_anonymous_variable_index++);
771 static void MC_dwarf_handle_variable_die(mc_object_info_t info, Dwarf_Die* die, Dwarf_Die* unit, dw_frame_t frame, const char* namespace) {
772 dw_variable_t variable = MC_die_to_variable(info, die, unit, frame, namespace);
775 MC_dwarf_register_variable(info, frame, variable);
778 static void mc_frame_free_voipd(dw_frame_t* p) {
783 static void MC_dwarf_handle_scope_die(mc_object_info_t info, Dwarf_Die* die, Dwarf_Die* unit, dw_frame_t parent_frame, const char* namespace) {
784 // TODO, handle DW_TAG_type/DW_TAG_location for DW_TAG_with_stmt
785 int tag = dwarf_tag(die);
786 mc_tag_class klass = MC_dwarf_tag_classify(tag);
788 // (Template) Subprogram declaration:
789 if(klass==mc_tag_subprogram && MC_dwarf_attr_flag(die, DW_AT_declaration, false))
792 if(klass==mc_tag_scope)
793 xbt_assert(parent_frame, "No parent scope for this scope");
795 dw_frame_t frame = xbt_new0(s_dw_frame_t, 1);
798 frame->id = dwarf_dieoffset(die);
799 frame->object_info = info;
801 if(klass==mc_tag_subprogram) {
802 const char* name = MC_dwarf_attr_integrate_string(die, DW_AT_name);
803 frame->name = namespace ? bprintf("%s::%s", namespace, name) : xbt_strdup(name);
806 frame->abstract_origin_id = MC_dwarf_attr_dieoffset(die, DW_AT_abstract_origin);
808 // This is the base address for DWARF addresses.
809 // Relocated addresses are offset from this base address.
810 // See DWARF4 spec 7.5
811 void* base = MC_object_base_address(info);
813 // Variables are filled in the (recursive) call of MC_dwarf_handle_children:
814 frame->variables = xbt_dynar_new(sizeof(dw_variable_t), dw_variable_free_voidp);
816 // TODO, support DW_AT_ranges
817 uint64_t low_pc = MC_dwarf_attr_integrate_addr(die, DW_AT_low_pc);
818 frame->low_pc = low_pc ? ((char*) base) + low_pc : 0;
821 Dwarf_Attribute attr;
822 if(!dwarf_attr_integrate(die, DW_AT_high_pc, &attr)) {
823 xbt_die("Missing DW_AT_high_pc matching with DW_AT_low_pc");
829 switch(MC_dwarf_form_get_class(dwarf_whatform(&attr))) {
831 // DW_AT_high_pc if an offset from the low_pc:
832 case MC_DW_CLASS_CONSTANT:
834 if (dwarf_formsdata(&attr, &offset) !=0)
835 xbt_die("Could not read constant");
836 frame->high_pc = (void*) ((char*)frame->low_pc + offset);
839 // DW_AT_high_pc is a relocatable address:
840 case MC_DW_CLASS_ADDRESS:
841 if (dwarf_formaddr(&attr, &high_pc) != 0)
842 xbt_die("Could not read address");
843 frame->high_pc = ((char*) base) + high_pc;
847 xbt_die("Unexpected class for DW_AT_high_pc");
852 if(klass==mc_tag_subprogram) {
853 Dwarf_Attribute attr_frame_base;
854 if (dwarf_attr_integrate(die, DW_AT_frame_base, &attr_frame_base))
855 mc_dwarf_location_list_init(&frame->frame_base, info, die, &attr_frame_base);
858 frame->scopes = xbt_dynar_new(sizeof(dw_frame_t), (void_f_pvoid_t) mc_frame_free_voipd);
861 if(klass==mc_tag_subprogram) {
862 char* key = bprintf("%" PRIx64, (uint64_t) frame->id);
863 xbt_dict_set(info->subprograms, key, frame, NULL);
865 } else if(klass==mc_tag_scope) {
866 xbt_dynar_push(parent_frame->scopes, &frame);
870 MC_dwarf_handle_children(info, die, unit, frame, namespace);
873 static void mc_dwarf_handle_namespace_die(
874 mc_object_info_t info, Dwarf_Die* die, Dwarf_Die* unit, dw_frame_t frame, const char* namespace) {
875 const char* name = MC_dwarf_attr_integrate_string(die, DW_AT_name);
877 xbt_die("Unexpected namespace in a subprogram");
878 char* new_namespace = namespace == NULL ? xbt_strdup(name)
879 : bprintf("%s::%s", namespace, name);
880 MC_dwarf_handle_children(info, die, unit, frame, new_namespace);
881 xbt_free(new_namespace);
884 static void MC_dwarf_handle_children(mc_object_info_t info, Dwarf_Die* die, Dwarf_Die* unit, dw_frame_t frame, const char* namespace) {
885 // For each child DIE:
888 for (res=dwarf_child(die, &child); res==0; res=dwarf_siblingof(&child,&child)) {
889 MC_dwarf_handle_die(info, &child, unit, frame, namespace);
893 static void MC_dwarf_handle_die(mc_object_info_t info, Dwarf_Die* die, Dwarf_Die* unit, dw_frame_t frame, const char* namespace) {
894 int tag = dwarf_tag(die);
895 mc_tag_class klass = MC_dwarf_tag_classify(tag);
900 MC_dwarf_handle_type_die(info, die, unit, frame, namespace);
903 // Subprogram or scope:
904 case mc_tag_subprogram:
906 MC_dwarf_handle_scope_die(info, die, unit, frame, namespace);
910 case mc_tag_variable:
911 MC_dwarf_handle_variable_die(info, die, unit, frame, namespace);
914 case mc_tag_namespace:
915 mc_dwarf_handle_namespace_die(info, die, unit, frame, namespace);
924 /** \brief Populate the debugging informations of the given ELF object
926 * Read the DWARf information of the EFFL object and populate the
927 * lists of types, variables, functions.
929 void MC_dwarf_get_variables(mc_object_info_t info) {
930 int fd = open(info->file_name, O_RDONLY);
932 xbt_die("Could not open file %s", info->file_name);
934 Dwarf *dwarf = dwarf_begin(fd, DWARF_C_READ);
936 xbt_die("Your program must be compiled with -g");
939 // For each compilation unit:
940 Dwarf_Off offset = 0;
941 Dwarf_Off next_offset = 0;
943 while (dwarf_nextcu (dwarf, offset, &next_offset, &length, NULL, NULL, NULL) == 0) {
945 if(dwarf_offdie(dwarf, offset+length, &unit_die)!=NULL) {
947 // For each child DIE:
950 for (res=dwarf_child(&unit_die, &child); res==0; res=dwarf_siblingof(&child,&child)) {
951 MC_dwarf_handle_die(info, &child, &unit_die, NULL, NULL);
955 offset = next_offset;