mirror of
https://github.com/N64Recomp/N64Recomp.git
synced 2025-05-14 08:12:19 +00:00
601 lines
31 KiB
C++
601 lines
31 KiB
C++
#include <optional>
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#include "fmt/format.h"
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// #include "fmt/ostream.h"
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#include "recompiler/context.h"
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#include "elfio/elfio.hpp"
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bool read_symbols(N64Recomp::Context& context, const ELFIO::elfio& elf_file, ELFIO::section* symtab_section, const N64Recomp::ElfParsingConfig& elf_config, bool dumping_context, std::unordered_map<uint16_t, std::vector<N64Recomp::DataSymbol>>& data_syms) {
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bool found_entrypoint_func = false;
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ELFIO::symbol_section_accessor symbols{ elf_file, symtab_section };
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std::unordered_map<uint16_t, uint16_t> bss_section_to_target_section{};
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// Create a mapping of bss section to the corresponding non-bss section. This is only used when dumping context in order
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// for patches and mods to correctly relocate symbols in bss. This mapping only matters for relocatable sections.
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if (dumping_context) {
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// Process bss and reloc sections
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for (size_t cur_section_index = 0; cur_section_index < context.sections.size(); cur_section_index++) {
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const N64Recomp::Section& cur_section = context.sections[cur_section_index];
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// Check if a bss section was found that corresponds with this section.
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if (cur_section.bss_section_index != (uint16_t)-1) {
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bss_section_to_target_section[cur_section.bss_section_index] = cur_section_index;
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}
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}
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}
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for (int sym_index = 0; sym_index < symbols.get_symbols_num(); sym_index++) {
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std::string name;
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ELFIO::Elf64_Addr value;
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ELFIO::Elf_Xword size;
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unsigned char bind;
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unsigned char type;
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ELFIO::Elf_Half section_index;
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unsigned char other;
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bool ignored = false;
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bool reimplemented = false;
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bool recorded_symbol = false;
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// Read symbol properties
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symbols.get_symbol(sym_index, name, value, size, bind, type,
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section_index, other);
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if (section_index == ELFIO::SHN_ABS && elf_config.use_absolute_symbols) {
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uint32_t vram = static_cast<uint32_t>(value);
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context.functions_by_vram[vram].push_back(context.functions.size());
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context.functions.emplace_back(
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vram,
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0,
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std::vector<uint32_t>{},
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std::move(name),
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0,
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true,
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reimplemented,
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false
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);
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continue;
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}
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if (section_index < context.sections.size()) {
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// Check if this symbol is the entrypoint
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// TODO this never fires, the check is broken due to signedness
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if (elf_config.has_entrypoint && value == elf_config.entrypoint_address && type == ELFIO::STT_FUNC) {
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if (found_entrypoint_func) {
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fmt::print(stderr, "Ambiguous entrypoint: {}\n", name);
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return false;
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}
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found_entrypoint_func = true;
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fmt::print("Found entrypoint, original name: {}\n", name);
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size = 0x50; // dummy size for entrypoints, should cover them all
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name = "recomp_entrypoint";
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}
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// Check if this symbol has a size override
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auto size_find = elf_config.manually_sized_funcs.find(name);
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if (size_find != elf_config.manually_sized_funcs.end()) {
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size = size_find->second;
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type = ELFIO::STT_FUNC;
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}
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if (!dumping_context) {
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if (N64Recomp::reimplemented_funcs.contains(name)) {
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reimplemented = true;
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name = name + "_recomp";
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ignored = true;
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} else if (N64Recomp::ignored_funcs.contains(name)) {
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name = name + "_recomp";
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ignored = true;
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}
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}
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auto& section = context.sections[section_index];
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// Check if this symbol is a function or has no type (like a regular glabel would)
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// Symbols with no type have a dummy entry created so that their symbol can be looked up for function calls
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if (ignored || type == ELFIO::STT_FUNC || type == ELFIO::STT_NOTYPE || type == ELFIO::STT_OBJECT) {
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if (!dumping_context) {
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if (N64Recomp::renamed_funcs.contains(name)) {
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name = name + "_recomp";
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ignored = false;
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}
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}
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if (section_index < context.sections.size()) {
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auto section_offset = value - elf_file.sections[section_index]->get_address();
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const uint32_t* words = reinterpret_cast<const uint32_t*>(elf_file.sections[section_index]->get_data() + section_offset);
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uint32_t vram = static_cast<uint32_t>(value);
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uint32_t num_instructions = type == ELFIO::STT_FUNC ? size / 4 : 0;
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uint32_t rom_address = static_cast<uint32_t>(section_offset + section.rom_addr);
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section.function_addrs.push_back(vram);
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context.functions_by_vram[vram].push_back(context.functions.size());
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// Find the entrypoint by rom address in case it doesn't have vram as its value
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if (elf_config.has_entrypoint && rom_address == 0x1000 && type == ELFIO::STT_FUNC) {
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vram = elf_config.entrypoint_address;
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found_entrypoint_func = true;
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name = "recomp_entrypoint";
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if (size == 0) {
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num_instructions = 0x50 / 4;
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}
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}
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// Suffix local symbols to prevent name conflicts.
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if (bind == ELFIO::STB_LOCAL) {
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name = fmt::format("{}_{:08X}", name, rom_address);
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}
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if (num_instructions > 0) {
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context.section_functions[section_index].push_back(context.functions.size());
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recorded_symbol = true;
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}
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context.functions_by_name[name] = context.functions.size();
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std::vector<uint32_t> insn_words(num_instructions);
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insn_words.assign(words, words + num_instructions);
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context.functions.emplace_back(
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vram,
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rom_address,
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std::move(insn_words),
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name,
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section_index,
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ignored,
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reimplemented
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);
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} else {
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// TODO is this case needed anymore?
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uint32_t vram = static_cast<uint32_t>(value);
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section.function_addrs.push_back(vram);
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context.functions_by_vram[vram].push_back(context.functions.size());
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context.functions.emplace_back(
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vram,
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0,
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std::vector<uint32_t>{},
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name,
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section_index,
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ignored,
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reimplemented
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);
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}
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}
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}
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// The symbol wasn't detected as a function, so add it to the data symbols if the context is being dumped.
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if (!recorded_symbol && dumping_context && !name.empty()) {
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// Skip internal symbols.
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if (ELF_ST_VISIBILITY(other) != ELFIO::STV_INTERNAL) {
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uint32_t vram = static_cast<uint32_t>(value);
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// Place this symbol in the absolute symbol list if it's in the absolute section.
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uint16_t target_section_index = section_index;
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if (section_index == ELFIO::SHN_ABS) {
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target_section_index = N64Recomp::SectionAbsolute;
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}
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else if (section_index >= context.sections.size()) {
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fmt::print("Symbol \"{}\" not in a valid section ({})\n", name, section_index);
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}
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// Move this symbol into the corresponding non-bss section if it's in a bss section.
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auto find_bss_it = bss_section_to_target_section.find(target_section_index);
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if (find_bss_it != bss_section_to_target_section.end()) {
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target_section_index = find_bss_it->second;
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}
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data_syms[target_section_index].emplace_back(
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vram,
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std::move(name)
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);
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}
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}
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}
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return found_entrypoint_func;
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}
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struct SegmentEntry {
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ELFIO::Elf64_Off data_offset;
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ELFIO::Elf64_Addr physical_address;
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ELFIO::Elf_Xword memory_size;
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};
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std::optional<size_t> get_segment(const std::vector<SegmentEntry>& segments, ELFIO::Elf_Xword section_size, ELFIO::Elf64_Off section_offset) {
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// A linear search is safest even if the segment list is sorted, as there may be overlapping segments
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for (size_t i = 0; i < segments.size(); i++) {
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const auto& segment = segments[i];
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// Check that the section's data in the elf file is within bounds of the segment's data
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if (section_offset >= segment.data_offset && section_offset + section_size <= segment.data_offset + segment.memory_size) {
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return i;
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}
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}
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return std::nullopt;
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}
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ELFIO::section* read_sections(N64Recomp::Context& context, const N64Recomp::ElfParsingConfig& elf_config, const ELFIO::elfio& elf_file) {
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ELFIO::section* symtab_section = nullptr;
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std::vector<SegmentEntry> segments{};
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segments.resize(elf_file.segments.size());
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bool has_reference_symbols = context.has_reference_symbols();
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// Copy the data for each segment into the segment entry list
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for (size_t segment_index = 0; segment_index < elf_file.segments.size(); segment_index++) {
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const auto& segment = *elf_file.segments[segment_index];
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segments[segment_index].data_offset = segment.get_offset();
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segments[segment_index].physical_address = segment.get_physical_address();
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segments[segment_index].memory_size = segment.get_file_size();
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}
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//// Sort the segments by physical address
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//std::sort(segments.begin(), segments.end(),
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// [](const SegmentEntry& lhs, const SegmentEntry& rhs) {
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// return lhs.data_offset < rhs.data_offset;
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// }
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//);
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std::unordered_map<std::string, ELFIO::section*> reloc_sections_by_name;
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std::unordered_map<std::string, ELFIO::section*> bss_sections_by_name;
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// First pass over the sections to find the load addresses and track the minimum load address value. This mimics the objcopy raw binary output behavior.
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uint32_t min_load_address = (uint32_t)-1;
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for (const auto& section : elf_file.sections) {
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auto& section_out = context.sections[section->get_index()];
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ELFIO::Elf_Word type = section->get_type();
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ELFIO::Elf_Xword flags = section->get_flags();
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ELFIO::Elf_Xword section_size = section->get_size();
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// Check if this section will end up in the ROM. It must not be a nobits (NOLOAD) type, must have the alloc flag set and must have a nonzero size.
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if (type != ELFIO::SHT_NOBITS && (flags & ELFIO::SHF_ALLOC) && section_size != 0) {
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std::optional<size_t> segment_index = get_segment(segments, section_size, section->get_offset());
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if (!segment_index.has_value()) {
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fmt::print(stderr, "Could not find segment that section {} belongs to!\n", section->get_name());
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return nullptr;
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}
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const SegmentEntry& segment = segments[segment_index.value()];
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// Calculate the load address of the section based on that of the segment.
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// This will get modified afterwards in the next pass to offset by the minimum load address.
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section_out.rom_addr = segment.physical_address + (section->get_offset() - segment.data_offset);
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// Track the minimum load address.
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min_load_address = std::min(min_load_address, section_out.rom_addr);
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}
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else {
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// Otherwise mark this section as having an invalid rom address
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section_out.rom_addr = (uint32_t)-1;
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}
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}
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// Iterate over every section to record rom addresses and find the symbol table
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for (const auto& section : elf_file.sections) {
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auto& section_out = context.sections[section->get_index()];
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//fmt::print(" {}: {} @ 0x{:08X}, 0x{:08X}\n", section->get_index(), section->get_name(), section->get_address(), context.rom.size());
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// Set the rom address of this section to the current accumulated ROM size
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section_out.ram_addr = section->get_address();
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section_out.size = section->get_size();
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ELFIO::Elf_Word type = section->get_type();
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std::string section_name = section->get_name();
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// Check if this section is the symbol table and record it if so
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if (type == ELFIO::SHT_SYMTAB) {
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symtab_section = section.get();
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}
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if (elf_config.all_sections_relocatable || elf_config.relocatable_sections.contains(section_name)) {
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section_out.relocatable = true;
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}
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// Check if this section is a reloc section
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if (type == ELFIO::SHT_REL) {
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// If it is, determine the name of the section it relocates
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if (!section_name.starts_with(".rel")) {
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fmt::print(stderr, "Could not determine corresponding section for reloc section {}\n", section_name.c_str());
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return nullptr;
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}
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// FIXME This should be using SH_INFO to create a reloc section to target section mapping instead of using the name.
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std::string reloc_target_section = section_name.substr(strlen(".rel"));
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// If this reloc section is for a section that has been marked as relocatable, record it in the reloc section lookup.
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// Alternatively, if this recompilation uses reference symbols then record all reloc sections.
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bool section_is_relocatable = elf_config.all_sections_relocatable || elf_config.relocatable_sections.contains(reloc_target_section);
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if (has_reference_symbols || section_is_relocatable) {
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reloc_sections_by_name[reloc_target_section] = section.get();
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}
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}
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// If the section is bss (SHT_NOBITS) and ends with the bss suffix, add it to the bss section map
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if (type == ELFIO::SHT_NOBITS && section_name.ends_with(elf_config.bss_section_suffix)) {
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std::string bss_target_section = section_name.substr(0, section_name.size() - elf_config.bss_section_suffix.size());
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// If this bss section is for a section that has been marked as relocatable, record it in the reloc section lookup
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if (elf_config.all_sections_relocatable || elf_config.relocatable_sections.contains(bss_target_section)) {
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bss_sections_by_name[bss_target_section] = section.get();
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}
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}
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// If this section was marked as being in the ROM in the previous pass, copy it into the ROM now.
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if (section_out.rom_addr != (uint32_t)-1) {
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// Adjust the section's final ROM address to account for the minimum load address.
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section_out.rom_addr -= min_load_address;
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// Resize the output rom if needed to fit this section.
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size_t required_rom_size = section_out.rom_addr + section_out.size;
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if (required_rom_size > context.rom.size()) {
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context.rom.resize(required_rom_size);
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}
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// Copy this section's data into the rom.
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std::copy(section->get_data(), section->get_data() + section->get_size(), &context.rom[section_out.rom_addr]);
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}
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// Check if this section is marked as executable, which means it has code in it
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if (section->get_flags() & ELFIO::SHF_EXECINSTR) {
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section_out.executable = true;
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}
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section_out.name = section_name;
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}
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if (symtab_section == nullptr) {
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fmt::print(stderr, "No symtab section found\n");
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return nullptr;
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}
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ELFIO::symbol_section_accessor symbol_accessor{ elf_file, symtab_section };
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auto num_syms = symbol_accessor.get_symbols_num();
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// TODO make sure that a reloc section was found for every section marked as relocatable
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// Process bss and reloc sections
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for (size_t section_index = 0; section_index < context.sections.size(); section_index++) {
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N64Recomp::Section& section_out = context.sections[section_index];
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// Check if a bss section was found that corresponds with this section
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auto bss_find = bss_sections_by_name.find(section_out.name);
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if (bss_find != bss_sections_by_name.end()) {
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section_out.bss_section_index = bss_find->second->get_index();
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section_out.bss_size = bss_find->second->get_size();
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context.bss_section_to_section[section_out.bss_section_index] = section_index;
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}
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// Check if this section is in the ROM and relocatable.
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const ELFIO::section* elf_section = elf_file.sections[section_index];
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bool in_rom = (elf_section->get_type() != ELFIO::SHT_NOBITS) && (elf_section->get_flags() & ELFIO::SHF_ALLOC);
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bool is_relocatable = section_out.relocatable || context.has_reference_symbols();
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if (in_rom && is_relocatable) {
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// Check if a reloc section was found that corresponds with this section
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auto reloc_find = reloc_sections_by_name.find(section_out.name);
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if (reloc_find != reloc_sections_by_name.end()) {
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// Create an accessor for the reloc section
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ELFIO::relocation_section_accessor rel_accessor{ elf_file, reloc_find->second };
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// Allocate space for the relocs in this section
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section_out.relocs.resize(rel_accessor.get_entries_num());
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// Track whether the previous reloc was a HI16 and its previous full_immediate
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bool prev_hi = false;
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// Track whether the previous reloc was a LO16
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bool prev_lo = false;
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uint32_t prev_hi_immediate = 0;
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uint32_t prev_hi_symbol = std::numeric_limits<uint32_t>::max();
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for (size_t i = 0; i < section_out.relocs.size(); i++) {
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// Get the current reloc
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ELFIO::Elf64_Addr rel_offset;
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ELFIO::Elf_Word rel_symbol;
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unsigned int rel_type;
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ELFIO::Elf_Sxword bad_rel_addend; // Addends aren't encoded in the reloc, so ignore this one
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rel_accessor.get_entry(i, rel_offset, rel_symbol, rel_type, bad_rel_addend);
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N64Recomp::Reloc& reloc_out = section_out.relocs[i];
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// Get the real full_immediate by extracting the immediate from the instruction
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uint32_t reloc_rom_addr = section_out.rom_addr + rel_offset - section_out.ram_addr;
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uint32_t reloc_rom_word = byteswap(*reinterpret_cast<const uint32_t*>(context.rom.data() + reloc_rom_addr));
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//context.rom section_out.rom_addr;
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reloc_out.address = rel_offset;
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reloc_out.symbol_index = rel_symbol;
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reloc_out.type = static_cast<N64Recomp::RelocType>(rel_type);
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std::string rel_symbol_name;
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ELFIO::Elf64_Addr rel_symbol_value;
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ELFIO::Elf_Xword rel_symbol_size;
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unsigned char rel_symbol_bind;
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unsigned char rel_symbol_type;
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ELFIO::Elf_Half rel_symbol_section_index;
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unsigned char rel_symbol_other;
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bool found_rel_symbol = symbol_accessor.get_symbol(
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rel_symbol, rel_symbol_name, rel_symbol_value, rel_symbol_size, rel_symbol_bind, rel_symbol_type, rel_symbol_section_index, rel_symbol_other);
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uint32_t rel_section_vram = 0;
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uint32_t rel_symbol_offset = 0;
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// Remap relocations from the current section's bss section to itself.
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// TODO Do this for any bss section and not just the current section's bss section?
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if (rel_symbol_section_index == section_out.bss_section_index) {
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rel_symbol_section_index = section_index;
|
|
}
|
|
|
|
// Check if the symbol is undefined and to know whether to look for it in the reference symbols.
|
|
if (rel_symbol_section_index == ELFIO::SHN_UNDEF) {
|
|
// Undefined sym, check the reference symbols.
|
|
N64Recomp::SymbolReference sym_ref;
|
|
if (!context.find_reference_symbol(rel_symbol_name, sym_ref)) {
|
|
fmt::print(stderr, "Undefined symbol: {}, not found in input or reference symbols!\n",
|
|
rel_symbol_name);
|
|
return nullptr;
|
|
}
|
|
|
|
reloc_out.reference_symbol = true;
|
|
// Replace the reloc's symbol index with the index into the reference symbol array.
|
|
rel_section_vram = 0;
|
|
reloc_out.target_section = sym_ref.section_index;
|
|
reloc_out.symbol_index = sym_ref.symbol_index;
|
|
const auto& reference_symbol = context.get_reference_symbol(reloc_out.target_section, reloc_out.symbol_index);
|
|
rel_symbol_offset = reference_symbol.section_offset;
|
|
|
|
bool target_section_relocatable = context.is_reference_section_relocatable(reloc_out.target_section);
|
|
|
|
if (reloc_out.type == N64Recomp::RelocType::R_MIPS_32 && target_section_relocatable) {
|
|
fmt::print(stderr, "Cannot reference {} in a statically initialized variable as it's defined in a relocatable section!\n",
|
|
rel_symbol_name);
|
|
return nullptr;
|
|
}
|
|
}
|
|
else if (rel_symbol_section_index == ELFIO::SHN_ABS) {
|
|
reloc_out.reference_symbol = false;
|
|
reloc_out.target_section = N64Recomp::SectionAbsolute;
|
|
rel_section_vram = 0;
|
|
}
|
|
else {
|
|
reloc_out.reference_symbol = false;
|
|
reloc_out.target_section = rel_symbol_section_index;
|
|
// Handle special sections.
|
|
if (rel_symbol_section_index >= context.sections.size()) {
|
|
fmt::print(stderr, "Reloc {} references symbol {} which is in an unknown section 0x{:04X}!\n",
|
|
i, rel_symbol_name, rel_symbol_section_index);
|
|
return nullptr;
|
|
}
|
|
rel_section_vram = context.sections[rel_symbol_section_index].ram_addr;
|
|
}
|
|
|
|
// Reloc pairing, see MIPS System V ABI documentation page 4-18 (https://refspecs.linuxfoundation.org/elf/mipsabi.pdf)
|
|
if (reloc_out.type == N64Recomp::RelocType::R_MIPS_LO16) {
|
|
uint32_t rel_immediate = reloc_rom_word & 0xFFFF;
|
|
uint32_t full_immediate = (prev_hi_immediate << 16) + (int16_t)rel_immediate;
|
|
reloc_out.target_section_offset = full_immediate + rel_symbol_offset - rel_section_vram;
|
|
if (prev_hi) {
|
|
if (prev_hi_symbol != rel_symbol) {
|
|
fmt::print(stderr, "Paired HI16 and LO16 relocations have different symbols\n"
|
|
" LO16 reloc index {} in section {} referencing symbol {} with offset 0x{:08X}\n",
|
|
i, section_out.name, reloc_out.symbol_index, reloc_out.address);
|
|
return nullptr;
|
|
}
|
|
|
|
// Set the previous HI16 relocs' relocated address.
|
|
section_out.relocs[i - 1].target_section_offset = reloc_out.target_section_offset;
|
|
}
|
|
else {
|
|
// Orphaned LO16 reloc warnings.
|
|
if (elf_config.unpaired_lo16_warnings) {
|
|
if (prev_lo) {
|
|
// Don't warn if multiple LO16 in a row reference the same symbol, as some linkers will use this behavior.
|
|
if (prev_hi_symbol != rel_symbol) {
|
|
fmt::print(stderr, "[WARN] LO16 reloc index {} in section {} referencing symbol {} with offset 0x{:08X} follows LO16 with different symbol\n",
|
|
i, section_out.name, reloc_out.symbol_index, reloc_out.address);
|
|
}
|
|
}
|
|
else {
|
|
fmt::print(stderr, "[WARN] Unpaired LO16 reloc index {} in section {} referencing symbol {} with offset 0x{:08X}\n",
|
|
i, section_out.name, reloc_out.symbol_index, reloc_out.address);
|
|
}
|
|
}
|
|
// Even though this is an orphaned LO16 reloc, the previous calculation for the addend still follows the MIPS System V ABI documentation:
|
|
// "R_MIPS_LO16 entries without an R_MIPS_HI16 entry immediately preceding are orphaned and the previously defined
|
|
// R_MIPS_HI16 is used for computing the addend."
|
|
// Therefore, nothing needs to be done to the section_offset member.
|
|
}
|
|
prev_lo = true;
|
|
} else {
|
|
if (prev_hi) {
|
|
// This is an invalid elf as the MIPS System V ABI documentation states:
|
|
// "Each relocation type of R_MIPS_HI16 must have an associated R_MIPS_LO16 entry
|
|
// immediately following it in the list of relocations."
|
|
fmt::print(stderr, "Unpaired HI16 reloc index {} in section {} referencing symbol {} with offset 0x{:08X}\n",
|
|
i - 1, section_out.name, section_out.relocs[i - 1].symbol_index, section_out.relocs[i - 1].address);
|
|
return nullptr;
|
|
}
|
|
prev_lo = false;
|
|
}
|
|
|
|
if (reloc_out.type == N64Recomp::RelocType::R_MIPS_HI16) {
|
|
uint32_t rel_immediate = reloc_rom_word & 0xFFFF;
|
|
prev_hi = true;
|
|
prev_hi_immediate = rel_immediate;
|
|
prev_hi_symbol = rel_symbol;
|
|
} else {
|
|
prev_hi = false;
|
|
}
|
|
|
|
if (reloc_out.type == N64Recomp::RelocType::R_MIPS_32) {
|
|
// The reloc addend is just the existing word before relocation, so the section offset can just be the symbol's section offset.
|
|
// Incorporating the addend will be handled at load-time.
|
|
reloc_out.target_section_offset = rel_symbol_offset;
|
|
// TODO set section_out.has_mips32_relocs to true if this section should emit its mips32 relocs (mainly for TLB mapping).
|
|
|
|
if (reloc_out.reference_symbol) {
|
|
uint32_t reloc_target_section_addr = context.get_reference_section_vram(reloc_out.target_section);
|
|
// Patch the word in the ROM to incorporate the symbol's value.
|
|
uint32_t updated_reloc_word = reloc_rom_word + reloc_target_section_addr + reloc_out.target_section_offset;
|
|
*reinterpret_cast<uint32_t*>(context.rom.data() + reloc_rom_addr) = byteswap(updated_reloc_word);
|
|
}
|
|
}
|
|
|
|
if (reloc_out.type == N64Recomp::RelocType::R_MIPS_26) {
|
|
uint32_t rel_immediate = (reloc_rom_word & 0x3FFFFFF) << 2;
|
|
if (reloc_out.reference_symbol) {
|
|
// Reference symbol relocs have their section offset already calculated, so don't apply the R_MIPS26 rule for the upper 4 bits.
|
|
// TODO Find a way to unify this with the else case.
|
|
reloc_out.target_section_offset = rel_immediate + rel_symbol_offset - rel_section_vram;
|
|
}
|
|
else {
|
|
reloc_out.target_section_offset = rel_immediate + rel_symbol_offset + (section_out.ram_addr & 0xF0000000) - rel_section_vram;
|
|
}
|
|
}
|
|
}
|
|
}
|
|
|
|
// Sort this section's relocs by address, which allows for binary searching and more efficient iteration during recompilation.
|
|
// This is safe to do as the entire full_immediate in present in relocs due to the pairing that was done earlier, so the HI16 does not
|
|
// need to directly preceed the matching LO16 anymore.
|
|
std::sort(section_out.relocs.begin(), section_out.relocs.end(),
|
|
[](const N64Recomp::Reloc& a, const N64Recomp::Reloc& b) {
|
|
return a.address < b.address;
|
|
}
|
|
);
|
|
}
|
|
}
|
|
|
|
return symtab_section;
|
|
}
|
|
|
|
static void setup_context_for_elf(N64Recomp::Context& context, const ELFIO::elfio& elf_file) {
|
|
context.sections.resize(elf_file.sections.size());
|
|
context.section_functions.resize(elf_file.sections.size());
|
|
context.functions.reserve(1024);
|
|
context.functions_by_vram.reserve(context.functions.capacity());
|
|
context.functions_by_name.reserve(context.functions.capacity());
|
|
context.rom.reserve(8 * 1024 * 1024);
|
|
}
|
|
|
|
bool N64Recomp::Context::from_elf_file(const std::filesystem::path& elf_file_path, Context& out, const ElfParsingConfig& elf_config, bool for_dumping_context, DataSymbolMap& data_syms_out, bool& found_entrypoint_out) {
|
|
ELFIO::elfio elf_file;
|
|
|
|
if (!elf_file.load(elf_file_path.string())) {
|
|
fmt::print("Elf file not found\n");
|
|
return false;
|
|
}
|
|
|
|
if (elf_file.get_class() != ELFIO::ELFCLASS32) {
|
|
fmt::print("Incorrect elf class\n");
|
|
return false;
|
|
}
|
|
|
|
if (elf_file.get_encoding() != ELFIO::ELFDATA2MSB) {
|
|
fmt::print("Incorrect endianness\n");
|
|
return false;
|
|
}
|
|
|
|
setup_context_for_elf(out, elf_file);
|
|
|
|
// Read all of the sections in the elf and look for the symbol table section
|
|
ELFIO::section* symtab_section = read_sections(out, elf_config, elf_file);
|
|
|
|
// If no symbol table was found then exit
|
|
if (symtab_section == nullptr) {
|
|
return false;
|
|
}
|
|
|
|
// Read all of the symbols in the elf and look for the entrypoint function
|
|
found_entrypoint_out = read_symbols(out, elf_file, symtab_section, elf_config, for_dumping_context, data_syms_out);
|
|
|
|
return true;
|
|
}
|