1 /* Copyright (c) 2008-2013. The SimGrid Team.
2 * All rights reserved. */
3 /* This program is free software; you can redistribute it and/or modify it
4 * under the terms of the license (GNU LGPL) which comes with this package. */
8 #include <elfutils/libdw.h>
11 #include <simgrid_config.h>
13 #include <xbt/sysdep.h>
15 #include "mc_private.h"
17 XBT_LOG_NEW_DEFAULT_SUBCATEGORY(mc_dwarf, mc, "DWARF processing");
19 /** \brief The default DW_TAG_lower_bound for a given DW_AT_language.
21 * The default for a given language is defined in the DWARF spec.
23 * \param language consant as defined by the DWARf spec
25 static uint64_t MC_dwarf_default_lower_bound(int lang);
27 /** \brief Computes the the element_count of a DW_TAG_enumeration_type DIE
29 * This is the number of elements in a given array dimension.
31 * A reference of the compilation unit (DW_TAG_compile_unit) is
32 * needed because the default lower bound (when there is no DW_AT_lower_bound)
33 * depends of the language of the compilation unit (DW_AT_language).
35 * \param die DIE for the DW_TAG_enumeration_type or DW_TAG_subrange_type
36 * \param unit DIE of the DW_TAG_compile_unit
38 static uint64_t MC_dwarf_subrange_element_count(Dwarf_Die* die, Dwarf_Die* unit);
40 /** \brief Computes the number of elements of a given DW_TAG_array_type.
42 * \param die DIE for the DW_TAG_array_type
44 static uint64_t MC_dwarf_array_element_count(Dwarf_Die* die, Dwarf_Die* unit);
46 /** \brief Process a DIE
48 * \param info the resulting object fot the library/binary file (output)
49 * \param die the current DIE
50 * \param unit the DIE of the compile unit of the current DIE
51 * \param frame containg frame if any
53 static void MC_dwarf_handle_die(mc_object_info_t info, Dwarf_Die* die, Dwarf_Die* unit, dw_frame_t frame, const char* namespace);
55 /** \brief Process a type DIE
57 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);
59 /** \brief Calls MC_dwarf_handle_die on all childrend of the given die
61 * \param info the resulting object fot the library/binary file (output)
62 * \param die the current DIE
63 * \param unit the DIE of the compile unit of the current DIE
64 * \param frame containg frame if any
66 static void MC_dwarf_handle_children(mc_object_info_t info, Dwarf_Die* die, Dwarf_Die* unit, dw_frame_t frame, const char* namespace);
68 /** \brief Handle a variable (DW_TAG_variable or other)
70 * \param info the resulting object fot the library/binary file (output)
71 * \param die the current DIE
72 * \param unit the DIE of the compile unit of the current DIE
73 * \param frame containg frame if any
75 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);
77 /** \brief Convert a libdw DWARF expression into a MC representation of the location
79 * \param expr array of DWARf operations
80 * \param len number of elements
81 * \return a new MC expression
83 static dw_location_t MC_dwarf_get_expression(Dwarf_Op* expr, size_t len);
85 /** \brief Get the DW_TAG_type of the DIE
88 * \return DW_TAG_type attribute as a new string (NULL if none)
90 static char* MC_dwarf_at_type(Dwarf_Die* die);
92 /** \brief Get the name of an attribute (DW_AT_*) from its code
94 * \param attr attribute code (see the DWARF specification)
95 * \return name of the attribute
97 const char* MC_dwarf_attrname(int attr) {
99 #include "mc_dwarf_attrnames.h"
101 return "DW_AT_unknown";
105 /** \brief Get the name of a dwarf tag (DW_TAG_*) from its code
107 * \param tag tag code (see the DWARF specification)
108 * \return name of the tag
110 const char* MC_dwarf_tagname(int tag) {
112 #include "mc_dwarf_tagnames.h"
114 return "DW_TAG_invalid";
116 return "DW_TAG_unknown";
120 /** \brief A class of DWARF tags (DW_TAG_*)
122 typedef enum mc_tag_class {
131 static mc_tag_class MC_dwarf_tag_classify(int tag) {
134 case DW_TAG_array_type:
135 case DW_TAG_class_type:
136 case DW_TAG_enumeration_type:
138 case DW_TAG_pointer_type:
139 case DW_TAG_string_type:
140 case DW_TAG_structure_type:
141 case DW_TAG_subroutine_type:
142 case DW_TAG_union_type:
143 case DW_TAG_ptr_to_member_type:
144 case DW_TAG_set_type:
145 case DW_TAG_subrange_type:
146 case DW_TAG_base_type:
147 case DW_TAG_const_type:
148 case DW_TAG_file_type:
149 case DW_TAG_packed_type:
150 case DW_TAG_volatile_type:
151 case DW_TAG_restrict_type:
152 case DW_TAG_interface_type:
153 case DW_TAG_unspecified_type:
154 case DW_TAG_mutable_type:
155 case DW_TAG_shared_type:
158 case DW_TAG_subprogram:
159 return mc_tag_subprogram;
161 case DW_TAG_variable:
162 case DW_TAG_formal_parameter:
163 return mc_tag_variable;
165 case DW_TAG_lexical_block:
166 case DW_TAG_try_block:
167 case DW_TAG_inlined_subroutine:
170 case DW_TAG_namespace:
171 return mc_tag_namespace;
174 return mc_tag_unknown;
179 #define MC_DW_CLASS_UNKNOWN 0
180 #define MC_DW_CLASS_ADDRESS 1 // Location in the address space of the program
181 #define MC_DW_CLASS_BLOCK 2 // Arbitrary block of bytes
182 #define MC_DW_CLASS_CONSTANT 3
183 #define MC_DW_CLASS_STRING 3 // String
184 #define MC_DW_CLASS_FLAG 4 // Boolean
185 #define MC_DW_CLASS_REFERENCE 5 // Reference to another DIE
186 #define MC_DW_CLASS_EXPRLOC 6 // DWARF expression/location description
187 #define MC_DW_CLASS_LINEPTR 7
188 #define MC_DW_CLASS_LOCLISTPTR 8
189 #define MC_DW_CLASS_MACPTR 9
190 #define MC_DW_CLASS_RANGELISTPTR 10
192 static int MC_dwarf_form_get_class(int form) {
195 return MC_DW_CLASS_ADDRESS;
200 return MC_DW_CLASS_BLOCK;
207 return MC_DW_CLASS_CONSTANT;
210 return MC_DW_CLASS_STRING;
211 case DW_FORM_ref_addr:
216 case DW_FORM_ref_udata:
217 return MC_DW_CLASS_REFERENCE;
219 case DW_FORM_flag_present:
220 return MC_DW_CLASS_FLAG;
221 case DW_FORM_exprloc:
222 return MC_DW_CLASS_EXPRLOC;
226 return MC_DW_CLASS_UNKNOWN;
230 /** \brief Get the name of the tag of a given DIE
233 * \return name of the tag of this DIE
235 static inline const char* MC_dwarf_die_tagname(Dwarf_Die* die) {
236 return MC_dwarf_tagname(dwarf_tag(die));
241 /** \brief Get an attribute of a given DIE as a string
244 * \param attribute attribute
245 * \return value of the given attribute of the given DIE
247 static const char* MC_dwarf_attr_string(Dwarf_Die* die, int attribute) {
248 Dwarf_Attribute attr;
249 if (!dwarf_attr_integrate(die, attribute, &attr)) {
252 return dwarf_formstring(&attr);
256 /** \brief Get the linkage name of a DIE.
258 * Use either DW_AT_linkage_name or DW_AR_MIPS_linkage_name.
261 * \return linkage name of the given DIE (or NULL)
263 static const char* MC_dwarf_at_linkage_name(Dwarf_Die* die) {
264 const char* name = MC_dwarf_attr_string(die, DW_AT_linkage_name);
266 name = MC_dwarf_attr_string(die, DW_AT_MIPS_linkage_name);
270 /** \brief Create a location list from a given attribute
273 * \param attr the attribute
274 * \return MC specific representation of the location list represented by the given attribute
277 static dw_location_t MC_dwarf_get_location_list(mc_object_info_t info, Dwarf_Die* die, Dwarf_Attribute* attr) {
279 dw_location_t location = xbt_new0(s_dw_location_t, 1);
280 location->type = e_dw_loclist;
281 xbt_dynar_t loclist = xbt_dynar_new(sizeof(dw_location_entry_t), NULL);
282 location->location.loclist = loclist;
284 ptrdiff_t offset = 0;
285 Dwarf_Addr base, start, end;
291 offset = dwarf_getlocations(attr, offset, &base, &start, &end, &expr, &len);
295 xbt_die("Error while loading location list");
297 dw_location_entry_t new_entry = xbt_new0(s_dw_location_entry_t, 1);
299 void* base = info->flags & MC_OBJECT_INFO_EXECUTABLE ? 0 : MC_object_base_address(info);
301 new_entry->lowpc = (char*) base + start;
302 new_entry->highpc = (char*) base + end;
303 new_entry->location = MC_dwarf_get_expression(expr, len);
305 xbt_dynar_push(loclist, &new_entry);
310 /** \brief Find the frame base of a given frame
312 * \param ip Instruction pointer
316 void* mc_find_frame_base(void* ip, dw_frame_t frame, unw_cursor_t* unw_cursor) {
317 switch(frame->frame_base->type) {
321 for(loclist_cursor=0; loclist_cursor < xbt_dynar_length(frame->frame_base->location.loclist); loclist_cursor++){
322 dw_location_entry_t entry = xbt_dynar_get_as(frame->frame_base->location.loclist, loclist_cursor, dw_location_entry_t);
323 if((ip >= entry->lowpc) && (ip < entry->highpc)){
324 return (void*) MC_dwarf_resolve_location(unw_cursor, entry->location, NULL);
335 /** \brief Get the location expression or location list from an attribute
337 * Processes direct expressions as well as location lists.
340 * \param attr the attribute
341 * \return MC specific representation of the location represented by the given attribute
344 static dw_location_t MC_dwarf_get_location(mc_object_info_t info, Dwarf_Die* die, Dwarf_Attribute* attr) {
345 int form = dwarf_whatform(attr);
348 // The attribute is an DWARF location expression:
349 case DW_FORM_exprloc:
350 case DW_FORM_block1: // not in the spec
357 if (dwarf_getlocation(attr, &expr, &len))
358 xbt_die("Could not read location expression");
359 return MC_dwarf_get_expression(expr, len);
362 // The attribute is a reference to a location list entry:
363 case DW_FORM_sec_offset:
369 return MC_dwarf_get_location_list(info, die, attr);
374 xbt_die("Unexpected form %i list for location in attribute %s of <%p>%s",
376 MC_dwarf_attrname(attr->code),
377 (void*) dwarf_dieoffset(die),
378 MC_dwarf_attr_string(die, DW_AT_name));
383 /** \brief Get the location expression or location list from an attribute
385 * Processes direct expressions as well as location lists.
388 * \param attribute the attribute code
389 * \return MC specific representation of the location represented by the given attribute
392 static dw_location_t MC_dwarf_at_location(mc_object_info_t info, Dwarf_Die* die, int attribute) {
393 if(!dwarf_hasattr_integrate(die, attribute))
394 return xbt_new0(s_dw_location_t, 1);
396 Dwarf_Attribute attr;
397 dwarf_attr_integrate(die, attribute, &attr);
398 return MC_dwarf_get_location(info, die, &attr);
401 static char* MC_dwarf_at_type(Dwarf_Die* die) {
402 Dwarf_Attribute attr;
403 if (dwarf_hasattr_integrate(die, DW_AT_type)) {
404 dwarf_attr_integrate(die, DW_AT_type, &attr);
405 Dwarf_Die subtype_die;
406 if (dwarf_formref_die(&attr, &subtype_die)==NULL) {
407 xbt_die("Could not find DIE for type");
409 Dwarf_Off subtype_global_offset = dwarf_dieoffset(&subtype_die);
410 return bprintf("%" PRIx64 , subtype_global_offset);
415 static uint64_t MC_dwarf_attr_addr(Dwarf_Die* die, int attribute) {
416 Dwarf_Attribute attr;
417 if(dwarf_attr_integrate(die, attribute, &attr)==NULL)
420 if (dwarf_formaddr(&attr, &value) == 0)
421 return (uint64_t) value;
426 static uint64_t MC_dwarf_attr_uint(Dwarf_Die* die, int attribute, uint64_t default_value) {
427 Dwarf_Attribute attr;
428 if (dwarf_attr_integrate(die, attribute, &attr)==NULL)
429 return default_value;
431 return dwarf_formudata(dwarf_attr_integrate(die, attribute, &attr), &value) == 0 ? (uint64_t) value : default_value;
434 static bool MC_dwarf_attr_flag(Dwarf_Die* die, int attribute, int integrate) {
435 Dwarf_Attribute attr;
436 if ((integrate ? dwarf_attr_integrate(die, attribute, &attr)
437 : dwarf_attr(die, attribute, &attr))==0)
441 if (dwarf_formflag(&attr, &result))
442 xbt_die("Unexpected form for attribute %s",
443 MC_dwarf_attrname(attribute));
447 static uint64_t MC_dwarf_default_lower_bound(int lang) {
452 case DW_LANG_C_plus_plus:
456 case DW_LANG_ObjC_plus_plus:
462 case DW_LANG_Fortran77:
463 case DW_LANG_Fortran90:
464 case DW_LANG_Fortran95:
465 case DW_LANG_Modula2:
466 case DW_LANG_Pascal83:
468 case DW_LANG_Cobol74:
469 case DW_LANG_Cobol85:
472 xbt_die("No default MT_TAG_lower_bound for language %i and none given", lang);
477 static uint64_t MC_dwarf_subrange_element_count(Dwarf_Die* die, Dwarf_Die* unit) {
478 xbt_assert(dwarf_tag(die)==DW_TAG_enumeration_type ||dwarf_tag(die)==DW_TAG_subrange_type,
479 "MC_dwarf_subrange_element_count called with DIE of type %s", MC_dwarf_die_tagname(die));
481 // Use DW_TAG_count if present:
482 if (dwarf_hasattr_integrate(die, DW_AT_count)) {
483 return MC_dwarf_attr_uint(die, DW_AT_count, 0);
486 // Otherwise compute DW_TAG_upper_bound-DW_TAG_lower_bound + 1:
488 if (!dwarf_hasattr_integrate(die, DW_AT_upper_bound)) {
489 // This is not really 0, but the code expects this (we do not know):
492 uint64_t upper_bound = MC_dwarf_attr_uint(die, DW_AT_upper_bound, -1);
494 uint64_t lower_bound = 0;
495 if (dwarf_hasattr_integrate(die, DW_AT_lower_bound)) {
496 lower_bound = MC_dwarf_attr_uint(die, DW_AT_lower_bound, -1);
498 lower_bound = MC_dwarf_default_lower_bound(dwarf_srclang(unit));
500 return upper_bound - lower_bound + 1;
503 static uint64_t MC_dwarf_array_element_count(Dwarf_Die* die, Dwarf_Die* unit) {
504 xbt_assert(dwarf_tag(die)==DW_TAG_array_type,
505 "MC_dwarf_array_element_count called with DIE of type %s", MC_dwarf_die_tagname(die));
510 for (res=dwarf_child(die, &child); res==0; res=dwarf_siblingof(&child,&child)) {
511 int child_tag = dwarf_tag(&child);
512 if (child_tag==DW_TAG_subrange_type ||child_tag==DW_TAG_enumeration_type) {
513 result *= MC_dwarf_subrange_element_count(&child, unit);
521 Dwarf_Off MC_dwarf_resolve_location(unw_cursor_t* c, dw_location_t location, void* frame_pointer_address) {
523 switch (location->type){
525 if (xbt_dynar_length(location->location.compose) > 1){
526 return 0; /* TODO : location list with optimizations enabled */
528 dw_location_t location_entry = xbt_dynar_get_as(location->location.compose, 0, dw_location_t);
529 switch (location_entry->type){
531 unw_get_reg(c, location_entry->location.reg, &res);
533 case e_dw_bregister_op:
534 unw_get_reg(c, location_entry->location.breg_op.reg, &res);
535 return (Dwarf_Off) ((long)res + location_entry->location.breg_op.offset);
537 case e_dw_fbregister_op:
538 if (frame_pointer_address != NULL)
539 return (Dwarf_Off)((char *)frame_pointer_address + location_entry->location.fbreg_op);
543 return 0; /* FIXME : implement other cases (with optimizations enabled) */
553 static void MC_dwarf_fill_member_location(dw_type_t type, dw_type_t member, Dwarf_Die* child) {
554 if (dwarf_hasattr(child, DW_AT_data_bit_offset)) {
555 xbt_die("Can't groke DW_AT_data_bit_offset.");
558 if (!dwarf_hasattr_integrate(child, DW_AT_data_member_location)) {
559 if (type->type != DW_TAG_union_type) {
561 "Missing DW_AT_data_member_location field in DW_TAG_member %s of type <%p>%s",
562 member->name, type->id, type->name);
568 Dwarf_Attribute attr;
569 dwarf_attr_integrate(child, DW_AT_data_member_location, &attr);
570 int form = dwarf_whatform(&attr);
571 int klass = MC_dwarf_form_get_class(form);
573 case MC_DW_CLASS_EXPRLOC:
574 case MC_DW_CLASS_BLOCK:
575 // Location expression:
579 if (dwarf_getlocation(&attr, &expr, &len)) {
581 "Could not read location expression DW_AT_data_member_location in DW_TAG_member %s of type <%p>%s",
582 MC_dwarf_attr_string(child, DW_AT_name),
583 type->id, type->name);
585 if (len==1 && expr[0].atom == DW_OP_plus_uconst) {
586 member->offset = expr[0].number;
588 xbt_die("Can't groke this location expression yet.");
592 case MC_DW_CLASS_CONSTANT:
593 // Offset from the base address of the object:
596 if (!dwarf_formudata(&attr, &offset))
597 member->offset = offset;
599 xbt_die("Cannot get %s location <%p>%s",
600 MC_dwarf_attr_string(child, DW_AT_name),
601 type->id, type->name);
604 case MC_DW_CLASS_LOCLISTPTR:
605 // Reference to a location list:
607 case MC_DW_CLASS_REFERENCE:
608 // It's supposed to be possible in DWARF2 but I couldn't find its semantic
612 "Can't handle form class (%i) / form 0x%x as DW_AT_member_location",
618 static void MC_dwarf_add_members(mc_object_info_t info, Dwarf_Die* die, Dwarf_Die* unit, dw_type_t type) {
621 xbt_assert(!type->members);
622 type->members = xbt_dynar_new(sizeof(dw_type_t), (void(*)(void*))dw_type_free);
623 for (res=dwarf_child(die, &child); res==0; res=dwarf_siblingof(&child,&child)) {
624 if (dwarf_tag(&child)==DW_TAG_member) {
626 // Skip compile time constants:
627 if(dwarf_hasattr(&child, DW_AT_const_value))
630 // TODO, we should use another type (because is is not a type but a member)
631 dw_type_t member = xbt_new0(s_dw_type_t, 1);
635 const char* name = MC_dwarf_attr_string(&child, DW_AT_name);
637 member->name = xbt_strdup(name);
641 member->byte_size = MC_dwarf_attr_uint(&child, DW_AT_byte_size, 0);
642 member->element_count = -1;
643 member->dw_type_id = MC_dwarf_at_type(&child);
644 member->members = NULL;
645 member->is_pointer_type = 0;
648 if(dwarf_hasattr(&child, DW_AT_data_bit_offset)) {
649 xbt_die("Can't groke DW_AT_data_bit_offset.");
652 MC_dwarf_fill_member_location(type, member, &child);
654 if (!member->dw_type_id) {
655 xbt_die("Missing type for member %s of <%p>%s", member->name, type->id, type->name);
658 xbt_dynar_push(type->members, &member);
663 /** \brief Create a MC type object from a DIE
665 * \param info current object info object
666 * \param DIE (for a given type);
667 * \param unit compilation unit of the current DIE
668 * \return MC representation of the type
670 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) {
672 dw_type_t type = xbt_new0(s_dw_type_t, 1);
677 type->element_count = -1;
678 type->dw_type_id = NULL;
679 type->members = NULL;
680 type->is_pointer_type = 0;
683 type->type = dwarf_tag(die);
686 type->id = (void *) dwarf_dieoffset(die);
688 const char* name = MC_dwarf_attr_string(die, DW_AT_name);
690 type->name = xbt_strdup(name);
693 XBT_DEBUG("Processing type <%p>%s", type->id, type->name);
695 type->dw_type_id = MC_dwarf_at_type(die);
697 // Computation of the byte_size;
698 if (dwarf_hasattr_integrate(die, DW_AT_byte_size))
699 type->byte_size = MC_dwarf_attr_uint(die, DW_AT_byte_size, 0);
700 else if (type->type == DW_TAG_array_type || type->type==DW_TAG_structure_type || type->type==DW_TAG_class_type) {
702 if (dwarf_aggregate_size(die, &size)==0) {
703 type->byte_size = size;
707 switch (type->type) {
708 case DW_TAG_array_type:
709 type->element_count = MC_dwarf_array_element_count(die, unit);
710 // TODO, handle DW_byte_stride and (not) DW_bit_stride
713 case DW_TAG_pointer_type:
714 case DW_TAG_reference_type:
715 case DW_TAG_rvalue_reference_type:
716 type->is_pointer_type = 1;
719 case DW_TAG_structure_type:
720 case DW_TAG_union_type:
721 case DW_TAG_class_type:
722 MC_dwarf_add_members(info, die, unit, type);
723 char* new_namespace = namespace == NULL ? xbt_strdup(type->name)
724 : bprintf("%s::%s", namespace, type->name);
725 MC_dwarf_handle_children(info, die, unit, frame, new_namespace);
733 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) {
734 dw_type_t type = MC_dwarf_die_to_type(info, die, unit, frame, namespace);
736 char* key = bprintf("%" PRIx64, (uint64_t) type->id);
737 xbt_dict_set(info->types, key, type, NULL);
739 if(type->name && type->byte_size!=0) {
740 xbt_dict_set(info->types_by_name, type->name, type, NULL);
744 /** \brief Convert libdw location expresion elment into native one (or NULL in some cases) */
745 static dw_location_t MC_dwarf_get_expression_element(Dwarf_Op* op) {
746 dw_location_t element = xbt_new0(s_dw_location_t, 1);
747 uint8_t atom = op->atom;
748 if (atom >= DW_OP_reg0 && atom<= DW_OP_reg31) {
749 element->type = e_dw_register;
750 element->location.reg = atom - DW_OP_reg0;
752 else if (atom >= DW_OP_breg0 && atom<= DW_OP_breg31) {
753 element->type = e_dw_bregister_op;
754 element->location.reg = atom - DW_OP_breg0;
755 element->location.breg_op.offset = op->number;
757 else if (atom >= DW_OP_lit0 && atom<= DW_OP_lit31) {
758 element->type = e_dw_lit;
759 element->location.reg = atom - DW_OP_lit0;
763 element->type = e_dw_fbregister_op;
764 element->location.fbreg_op = op->number;
767 element->type = e_dw_piece;
768 element->location.piece = op->number;
770 case DW_OP_plus_uconst:
771 element->type = e_dw_plus_uconst;
772 element->location.plus_uconst = op->number;
775 element->type = e_dw_arithmetic;
776 element->location.arithmetic = xbt_strdup("abs");
779 element->type = e_dw_arithmetic;
780 element->location.arithmetic = xbt_strdup("and");
783 element->type = e_dw_arithmetic;
784 element->location.arithmetic = xbt_strdup("div");
787 element->type = e_dw_arithmetic;
788 element->location.arithmetic = xbt_strdup("minus");
791 element->type = e_dw_arithmetic;
792 element->location.arithmetic = xbt_strdup("mod");
795 element->type = e_dw_arithmetic;
796 element->location.arithmetic = xbt_strdup("mul");
799 element->type = e_dw_arithmetic;
800 element->location.arithmetic = xbt_strdup("neg");
803 element->type = e_dw_arithmetic;
804 element->location.arithmetic = xbt_strdup("not");
807 element->type = e_dw_arithmetic;
808 element->location.arithmetic = xbt_strdup("or");
811 element->type = e_dw_arithmetic;
812 element->location.arithmetic = xbt_strdup("plus");
815 case DW_OP_stack_value:
820 case DW_OP_deref_size:
821 element->type = e_dw_deref;
822 element->location.deref_size = (unsigned int short) op->number;
825 element->type = e_dw_deref;
826 element->location.deref_size = sizeof(void *);
829 element->type = e_dw_uconstant;
830 element->location.uconstant.bytes = 1;
831 element->location.uconstant.value = (unsigned long int) op->number;
834 element->type = e_dw_sconstant;
835 element->location.uconstant.bytes = 1;
836 element->location.uconstant.value = (unsigned long int) op->number;
840 element->type = e_dw_uconstant;
841 element->location.uconstant.bytes = 1;
842 element->location.uconstant.value = (unsigned long int) op->number;
845 element->type = e_dw_uconstant;
846 element->location.uconstant.bytes = 2;
847 element->location.uconstant.value = (unsigned long int) op->number;
850 element->type = e_dw_uconstant;
851 element->location.uconstant.bytes = 4;
852 element->location.uconstant.value = (unsigned long int) op->number;
855 element->type = e_dw_uconstant;
856 element->location.uconstant.bytes = 8;
857 element->location.uconstant.value = (unsigned long int) op->number;
861 element->type = e_dw_sconstant;
862 element->location.uconstant.bytes = 1;
863 element->location.uconstant.value = (unsigned long int) op->number;
866 element->type = e_dw_sconstant;
867 element->location.uconstant.bytes = 2;
868 element->location.uconstant.value = (unsigned long int) op->number;
871 element->type = e_dw_sconstant;
872 element->location.uconstant.bytes = 4;
873 element->location.uconstant.value = (unsigned long int) op->number;
876 element->type = e_dw_sconstant;
877 element->location.uconstant.bytes = 8;
878 element->location.uconstant.value = (unsigned long int) op->number;
881 element->type = e_dw_unsupported;
887 /** \brief Convert libdw location expresion into native one */
888 static dw_location_t MC_dwarf_get_expression(Dwarf_Op* expr, size_t len) {
889 dw_location_t loc = xbt_new0(s_dw_location_t, 1);
890 loc->type = e_dw_compose;
891 loc->location.compose = xbt_dynar_new(sizeof(dw_location_t), NULL);
894 for (i=0; i!=len; ++i) {
895 dw_location_t element = MC_dwarf_get_expression_element(expr+i);
897 xbt_dynar_push(loc->location.compose, &element);
903 static int mc_anonymous_variable_index = 0;
905 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) {
906 // Skip declarations:
907 if (MC_dwarf_attr_flag(die, DW_AT_declaration, false))
910 // Skip compile time constants:
911 if(dwarf_hasattr(die, DW_AT_const_value))
914 Dwarf_Attribute attr_location;
915 if (dwarf_attr(die, DW_AT_location, &attr_location)==NULL) {
916 // No location: do not add it ?
920 dw_variable_t variable = xbt_new0(s_dw_variable_t, 1);
921 variable->dwarf_offset = dwarf_dieoffset(die);
922 variable->global = frame == NULL; // Can be override base on DW_AT_location
924 const char* name = MC_dwarf_attr_string(die, DW_AT_name);
925 variable->name = xbt_strdup(name);
927 variable->type_origin = MC_dwarf_at_type(die);
929 int klass = MC_dwarf_form_get_class(dwarf_whatform(&attr_location));
931 case MC_DW_CLASS_EXPRLOC:
932 case MC_DW_CLASS_BLOCK:
933 // Location expression:
937 if (dwarf_getlocation(&attr_location, &expr, &len)) {
939 "Could not read location expression in DW_AT_location of variable <%p>%s",
940 (void*) variable->dwarf_offset, variable->name);
943 if (len==1 && expr[0].atom == DW_OP_addr) {
944 variable->global = 1;
945 Dwarf_Off offset = expr[0].number;
946 // TODO, Why is this different base on the object?
947 Dwarf_Off base = strcmp(info->file_name, xbt_binary_name) !=0 ? (Dwarf_Off) info->start_exec : 0;
948 variable->address = (void*) (base + offset);
950 variable->location = MC_dwarf_get_expression(expr, len);
955 case MC_DW_CLASS_LOCLISTPTR:
956 case MC_DW_CLASS_CONSTANT:
957 // Reference to location list:
958 variable->location = MC_dwarf_get_location_list(info, die, &attr_location);
961 xbt_die("Unexpected calss 0x%x (%i) list for location in <%p>%s",
962 klass, klass, (void*) variable->dwarf_offset, variable->name);
965 // Handle start_scope:
966 if (dwarf_hasattr(die, DW_AT_start_scope)) {
967 Dwarf_Attribute attr;
968 dwarf_attr(die, DW_AT_start_scope, &attr);
969 int form = dwarf_whatform(&attr);
970 int klass = MC_dwarf_form_get_class(form);
972 case MC_DW_CLASS_CONSTANT:
975 variable->start_scope = dwarf_formudata(&attr, &value) == 0 ? (size_t) value : 0;
979 xbt_die("Unhandled form 0x%x, class 0x%X for DW_AT_start_scope of variable %s",
980 form, klass, name==NULL ? "?" : name);
984 if(namespace && variable->global) {
985 char* old_name = variable->name;
986 variable->name = bprintf("%s::%s", namespace, old_name);
990 // The current code needs a variable name,
991 // generate a fake one:
992 if(!variable->name) {
993 variable->name = bprintf("@anonymous#%i", mc_anonymous_variable_index++);
999 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) {
1000 dw_variable_t variable = MC_die_to_variable(info, die, unit, frame, namespace);
1003 MC_dwarf_register_variable(info, frame, variable);
1006 static void MC_dwarf_handle_subprogram_die(mc_object_info_t info, Dwarf_Die* die, Dwarf_Die* unit, dw_frame_t parent_frame, const char* namespace) {
1007 dw_frame_t frame = xbt_new0(s_dw_frame_t, 1);
1009 frame->start = dwarf_dieoffset(die);
1011 const char* name = MC_dwarf_attr_string(die, DW_AT_name);
1012 frame->name = namespace ? bprintf("%s::%s", namespace, name) : xbt_strdup(name);
1014 // This is the base address for DWARF addresses.
1015 // Relocated addresses are offset from this base address.
1016 // See DWARF4 spec 7.5
1017 void* base = info->flags & MC_OBJECT_INFO_EXECUTABLE ? 0 : MC_object_base_address(info);
1019 // Variables are filled in the (recursive) call of MC_dwarf_handle_children:
1020 frame->variables = xbt_dynar_new(sizeof(dw_variable_t), dw_variable_free_voidp);
1021 frame->high_pc = ((char*) base) + MC_dwarf_attr_addr(die, DW_AT_high_pc);
1022 frame->low_pc = ((char*) base) + MC_dwarf_attr_addr(die, DW_AT_low_pc);
1023 frame->frame_base = MC_dwarf_at_location(info, die, DW_AT_frame_base);
1024 frame->end = -1; // This one is now useless:
1027 xbt_dynar_push(info->subprograms, &frame);
1030 MC_dwarf_handle_children(info, die, unit, frame, namespace);
1033 static void mc_dwarf_handle_namespace_die(
1034 mc_object_info_t info, Dwarf_Die* die, Dwarf_Die* unit, dw_frame_t frame, const char* namespace) {
1035 const char* name = MC_dwarf_attr_string(die, DW_AT_name);
1037 xbt_die("Unexpected namespace in a subprogram");
1038 char* new_namespace = namespace == NULL ? xbt_strdup(name)
1039 : bprintf("%s::%s", namespace, name);
1040 MC_dwarf_handle_children(info, die, unit, frame, new_namespace);
1043 static void MC_dwarf_handle_children(mc_object_info_t info, Dwarf_Die* die, Dwarf_Die* unit, dw_frame_t frame, const char* namespace) {
1046 for (res=dwarf_child(die, &child); res==0; res=dwarf_siblingof(&child,&child)) {
1047 MC_dwarf_handle_die(info, &child, unit, frame, namespace);
1051 static void MC_dwarf_handle_die(mc_object_info_t info, Dwarf_Die* die, Dwarf_Die* unit, dw_frame_t frame, const char* namespace) {
1052 int tag = dwarf_tag(die);
1053 mc_tag_class klass = MC_dwarf_tag_classify(tag);
1058 MC_dwarf_handle_type_die(info, die, unit, frame, namespace);
1062 case mc_tag_subprogram:
1063 MC_dwarf_handle_subprogram_die(info, die, unit, frame, namespace);
1067 case mc_tag_variable:
1068 MC_dwarf_handle_variable_die(info, die, unit, frame, namespace);
1076 case mc_tag_namespace:
1077 mc_dwarf_handle_namespace_die(info, die, unit, frame, namespace);
1086 void MC_dwarf_get_variables(mc_object_info_t info) {
1087 int fd = open(info->file_name, O_RDONLY);
1089 xbt_die("Could not open file %s", info->file_name);
1091 Dwarf *dwarf = dwarf_begin(fd, DWARF_C_READ);
1093 xbt_die("Your program must be compiled with -g");
1096 Dwarf_Off offset = 0;
1097 Dwarf_Off next_offset = 0;
1099 while (dwarf_nextcu (dwarf, offset, &next_offset, &length, NULL, NULL, NULL) == 0) {
1102 if(dwarf_offdie(dwarf, offset+length, &unit_die)!=NULL) {
1105 for (res=dwarf_child(&unit_die, &child); res==0; res=dwarf_siblingof(&child,&child)) {
1106 MC_dwarf_handle_die(info, &child, &unit_die, NULL, NULL);
1109 offset = next_offset;