1 /* Copyright (c) 2014-2019. The SimGrid Team. 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. */
10 #include "src/mc/inspect/Frame.hpp"
11 #include "src/mc/inspect/ObjectInformation.hpp"
12 #include "src/mc/inspect/Variable.hpp"
17 /* For an executable object, addresses are virtual address
18 * (there is no offset) i.e.
19 * \f$\text{virtual address} = \{dwarf address}\f$
21 * For a shared object, the addresses are offset from the begining
22 * of the shared object (the base address of the mapped shared
23 * object must be used as offset
24 * i.e. \f$\text{virtual address} = \text{shared object base address}
25 * + \text{dwarf address}\f$.
27 void* ObjectInformation::base_address() const
29 // For an executable (more precisely for a ET_EXEC) the base it 0:
30 if (this->executable())
33 // For an a shared-object (ET_DYN, including position-independent executables)
34 // the base address is its lowest address:
35 void* result = this->start_exec;
36 if (this->start_rw != nullptr && result > (void*)this->start_rw)
37 result = this->start_rw;
38 if (this->start_ro != nullptr && result > (void*)this->start_ro)
39 result = this->start_ro;
43 simgrid::mc::Frame* ObjectInformation::find_function(const void* ip) const
45 /* This is implemented by binary search on a sorted array.
47 * We do quite a lot of those so we want this to be cache efficient.
48 * We pack the only information we need in the index entries in order
49 * to successfully do the binary search. We do not need the high_pc
50 * during the binary search (only at the end) so it is not included
51 * in the index entry. We could use parallel arrays as well.
53 * We cannot really use the std:: algorithm for this.
54 * We could use std::binary_search by including the high_pc inside
55 * the FunctionIndexEntry.
57 const simgrid::mc::FunctionIndexEntry* base = this->functions_index.data();
59 int j = this->functions_index.size() - 1;
61 int k = i + ((j - i) / 2);
63 /* In most of the search, we do not dereference the base[k].function.
64 * This way the memory accesses are located in the base[k] array. */
65 if (ip < base[k].low_pc)
67 else if (k < j && ip >= base[k + 1].low_pc)
70 /* At this point, the search is over.
71 * Either we have found the correct function or we do not know
72 * any function corresponding to this instruction address.
73 * Only at the point do we dereference the function pointer. */
74 else if ((std::uint64_t)ip < base[k].function->range.end())
75 return base[k].function;
82 const simgrid::mc::Variable* ObjectInformation::find_variable(const char* name) const
84 for (simgrid::mc::Variable const& variable : this->global_variables)
85 if (variable.name == name)
90 void ObjectInformation::remove_global_variable(const char* name)
92 typedef std::vector<Variable>::size_type size_type;
94 if (this->global_variables.empty())
99 size_type last = this->global_variables.size() - 1;
101 while (first <= last) {
102 size_type cursor = first + (last - first) / 2;
103 simgrid::mc::Variable& current_var = this->global_variables[cursor];
104 int cmp = current_var.name.compare(name);
108 // Find the whole range:
110 while (first != 0 && this->global_variables[first - 1].name == name)
112 size_type size = this->global_variables.size();
114 while (last != size - 1 && this->global_variables[last + 1].name == name)
117 // Remove the whole range:
118 this->global_variables.erase(this->global_variables.begin() + first, this->global_variables.begin() + last + 1);
123 else if (cursor != 0)
130 /** Ignore a local variable in a scope
132 * Ignore all instances of variables with a given name in
133 * any (possibly inlined) subprogram with a given namespaced
136 * @param var_name Name of the local variable to ignore
137 * @param subprogram_name Name of the subprogram to ignore (nullptr for any)
138 * @param subprogram (possibly inlined) Subprogram of the scope current scope
139 * @param scope Current scope
141 static void remove_local_variable(simgrid::mc::Frame& scope, const char* var_name, const char* subprogram_name,
142 simgrid::mc::Frame const& subprogram)
144 typedef std::vector<Variable>::size_type size_type;
146 // If the current subprogram matches the given name:
147 if ((subprogram_name == nullptr || (not subprogram.name.empty() && subprogram.name == subprogram_name)) &&
148 not scope.variables.empty()) {
150 // Try to find the variable and remove it:
152 size_type end = scope.variables.size() - 1;
155 while (start <= end) {
156 size_type cursor = start + (end - start) / 2;
157 simgrid::mc::Variable& current_var = scope.variables[cursor];
158 int compare = current_var.name.compare(var_name);
160 // Variable found, remove it:
161 scope.variables.erase(scope.variables.begin() + cursor);
163 } else if (compare < 0)
165 else if (cursor != 0)
172 // And recursive processing in nested scopes:
173 for (simgrid::mc::Frame& nested_scope : scope.scopes) {
174 // The new scope may be an inlined subroutine, in this case we want to use its
175 // namespaced name in recursive calls:
176 simgrid::mc::Frame const& nested_subprogram =
177 nested_scope.tag == DW_TAG_inlined_subroutine ? nested_scope : subprogram;
178 remove_local_variable(nested_scope, var_name, subprogram_name, nested_subprogram);
182 void ObjectInformation::remove_local_variable(const char* var_name, const char* subprogram_name)
184 for (auto& entry : this->subprograms)
185 simgrid::mc::remove_local_variable(entry.second, var_name, subprogram_name, entry.second);
189 } // namespace simgrid