+++ /dev/null
-/* Copyright (c) 2014-2023. The SimGrid Team. All rights reserved. */
-
-/* This program is free software; you can redistribute it and/or modify it
- * under the terms of the license (GNU LGPL) which comes with this package. */
-
-#include <algorithm>
-#include <cstdint>
-#include <sys/mman.h> // PROT_READ and friends
-#include <vector>
-
-#include "src/mc/inspect/Frame.hpp"
-#include "src/mc/inspect/ObjectInformation.hpp"
-#include "src/mc/inspect/Variable.hpp"
-#include "src/mc/mc_private.hpp"
-#include "xbt/file.hpp"
-
-namespace simgrid::mc {
-
-/* For an executable object, addresses are virtual address (there is no offset) i.e.
- * \f$\text{virtual address} = \{dwarf address}\f$
- *
- * For a shared object, the addresses are offset from the beginning of the shared object (the base address of the
- * mapped shared object must be used as offset
- * i.e. \f$\text{virtual address} = \text{shared object base address}
- * + \text{dwarf address}\f$.
- */
-void* ObjectInformation::base_address() const
-{
- // For an executable (more precisely for an ET_EXEC) the base it 0:
- if (this->executable())
- return nullptr;
-
- // For an a shared-object (ET_DYN, including position-independent executables) the base address is its lowest address:
- void* result = this->start_exec;
- if (this->start_rw != nullptr && result > (void*)this->start_rw)
- result = this->start_rw;
- if (this->start_ro != nullptr && result > (void*)this->start_ro)
- result = this->start_ro;
- return result;
-}
-
-Frame* ObjectInformation::find_function(const void* ip)
-{
- ensure_dwarf_loaded();
-
- /* This is implemented by binary search on a sorted array.
- *
- * We do quite a lot of those so we want this to be cache efficient.
- * We pack the only information we need in the index entries in order
- * to successfully do the binary search. We do not need the high_pc
- * during the binary search (only at the end) so it is not included
- * in the index entry. We could use parallel arrays as well.
- *
- * Note the usage of reverse iterators to match the correct interval.
- */
- auto pos = std::lower_bound(this->functions_index.rbegin(), this->functions_index.rend(), ip,
- [](auto const& func, auto const* addr) { return func.low_pc > addr; });
-
- /* At this point, the search is over.
- * Either we have found the correct function or we do not know
- * any function corresponding to this instruction address.
- * Only at the point do we dereference the function pointer. */
- return (pos != this->functions_index.rend() && reinterpret_cast<std::uint64_t>(ip) < pos->function->range.end())
- ? pos->function
- : nullptr;
-}
-
-const Variable* ObjectInformation::find_variable(const char* var_name)
-{
- ensure_dwarf_loaded();
-
- auto pos = std::lower_bound(this->global_variables.begin(), this->global_variables.end(), var_name,
- [](auto const& var, const char* name) { return var.name < name; });
- return (pos != this->global_variables.end() && pos->name == var_name) ? &(*pos) : nullptr;
-}
-
-void ObjectInformation::remove_global_variable(const char* var_name)
-{
- // Binary search:
- auto pos1 = std::lower_bound(this->global_variables.begin(), this->global_variables.end(), var_name,
- [](auto const& var, const char* name) { return var.name < name; });
- // Find the whole range:
- auto pos2 = std::upper_bound(pos1, this->global_variables.end(), var_name,
- [](const char* name, auto const& var) { return name < var.name; });
- // Remove the whole range:
- this->global_variables.erase(pos1, pos2);
-}
-
-/** Ignore a local variable in a scope
- *
- * Ignore all instances of variables with a given name in any (possibly inlined) subprogram with a given namespaced
- * name.
- *
- * @param var_name Name of the local variable to ignore
- * @param subprogram_name Name of the subprogram to ignore (nullptr for any)
- * @param subprogram (possibly inlined) Subprogram of the scope current scope
- * @param scope Current scope
- */
-static void remove_local_variable(Frame& scope, const char* var_name, const char* subprogram_name,
- Frame const& subprogram)
-{
- // If the current subprogram matches the given name:
- if (subprogram_name == nullptr || (not subprogram.name.empty() && subprogram.name == subprogram_name)) {
- // Try to find the variable and remove it:
-
- // Binary search:
- auto pos = std::lower_bound(scope.variables.begin(), scope.variables.end(), var_name,
- [](auto const& var, const char* name) { return var.name < name; });
- if (pos != scope.variables.end() && pos->name == var_name) {
- // Variable found, remove it:
- scope.variables.erase(pos);
- }
- }
-
- // And recursive processing in nested scopes:
- for (Frame& nested_scope : scope.scopes) {
- // The new scope may be an inlined subroutine, in this case we want to use its
- // namespaced name in recursive calls:
- Frame const& nested_subprogram = nested_scope.tag == DW_TAG_inlined_subroutine ? nested_scope : subprogram;
- remove_local_variable(nested_scope, var_name, subprogram_name, nested_subprogram);
- }
-}
-
-void ObjectInformation::remove_local_variable(const char* var_name, const char* subprogram_name)
-{
- for (auto& [_, entry] : this->subprograms)
- mc::remove_local_variable(entry, var_name, subprogram_name, entry);
-}
-
-/** @brief Fills the position of the segments (executable, read-only, read/write) */
-// TODO, use the ELF segment information for more robustness
-void find_object_address(std::vector<xbt::VmMap> const& maps, ObjectInformation* result)
-{
- const int PROT_RW = PROT_READ | PROT_WRITE;
- const int PROT_RX = PROT_READ | PROT_EXEC;
-
- std::string name = xbt::Path(result->file_name).get_base_name();
-
- for (size_t i = 0; i < maps.size(); ++i) {
- simgrid::xbt::VmMap const& reg = maps[i];
- if (reg.pathname.empty() || name != simgrid::xbt::Path(reg.pathname).get_base_name())
- continue;
-
- // This is the non-GNU_RELRO-part of the data segment:
- if (reg.prot == PROT_RW) {
- xbt_assert(not result->start_rw, "Multiple read-write segments for %s, not supported", maps[i].pathname.c_str());
- result->start_rw = (char*)reg.start_addr;
- result->end_rw = (char*)reg.end_addr;
-
- // The next VMA might be end of the data segment:
- if (i + 1 < maps.size() && maps[i + 1].pathname.empty() && maps[i + 1].prot == PROT_RW &&
- maps[i + 1].start_addr == reg.end_addr)
- result->end_rw = (char*)maps[i + 1].end_addr;
- }
-
- // This is the text segment:
- else if (reg.prot == PROT_RX) {
- xbt_assert(not result->start_exec, "Multiple executable segments for %s, not supported",
- maps[i].pathname.c_str());
- result->start_exec = (char*)reg.start_addr;
- result->end_exec = (char*)reg.end_addr;
-
- // The next VMA might be end of the data segment:
- if (i + 1 < maps.size() && maps[i + 1].pathname.empty() && maps[i + 1].prot == PROT_RW &&
- maps[i + 1].start_addr == reg.end_addr) {
- result->start_rw = (char*)maps[i + 1].start_addr;
- result->end_rw = (char*)maps[i + 1].end_addr;
- }
- }
-
- // This is the GNU_RELRO-part of the data segment:
- else if (reg.prot == PROT_READ) {
- xbt_assert(not result->start_ro,
- "Multiple read-only segments for %s, not supported. Compiling with the following may help: "
- "-g -Wl,-znorelro -Wl,-znoseparate-code",
- maps[i].pathname.c_str());
- result->start_ro = (char*)reg.start_addr;
- result->end_ro = (char*)reg.end_addr;
- }
- }
-
- result->start = result->start_rw;
- if ((const void*)result->start_ro < result->start)
- result->start = result->start_ro;
- if ((const void*)result->start_exec < result->start)
- result->start = result->start_exec;
-
- result->end = result->end_rw;
- if (result->end_ro && (const void*)result->end_ro > result->end)
- result->end = result->end_ro;
- if (result->end_exec && (const void*)result->end_exec > result->end)
- result->end = result->end_exec;
-
- xbt_assert(result->start_exec || result->start_rw || result->start_ro);
-}
-
-} // namespace simgrid::mc
