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Modding Support PR 1 (Instruction tables, modding support, mod symbol format, library conversion) (#89)

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* Initial implementation of binary operation table

* Initial implementation of unary operation table

* More binary op types, moved binary expression string generation into separate function

* Added and implemented conditional branch instruction table

* Fixed likely swap on bgezal, fixed extra indent branch close and missing
indent on branch statement

* Add operands for other uses of float registers

* Added CHECK_FR generation to binary operation processing, moved float comparison instructions to binary op table

* Finished moving float arithmetic instructions to operation tables

* Added store instruction operation table

* Created Generator interface, separated operation types and tables and C generation code into new files

* Fix mov.d using the wrong input operand

* Move recompiler core logic into a core library and make the existing CLI consume the core library

* Removed unnecessary config input to recompilation functions

* Moved parts of recomp_port.h into new internal headers in src folder

* Changed recomp port naming to N64Recomp

* Remove some unused code and document which Context fields are actually required for recompilation

* Implement mod symbol parsing

* Restructure mod symbols to make replacements global instead of per-section

* Refactor elf parsing into static Context method for reusability

* Move elf parsing into a separate library

* WIP elf to mod tool, currently working without relocations or API exports/imports

* Make mod tool emit relocs and patch binary for non-relocatable symbol references as needed

* Implemented writing import and exports in the mod tool

* Add dependencies to the mod symbol format, finish exporting and importing of mod symbols

* Add first pass offline mod recompiler (generates C from mods that can be compiled and linked into a dynamic library)

* Add strict mode and ability to generate exports for normal recompilation (for patches)

* Move mod context fields into base context, move import symbols into separate vector, misc cleanup

* Some cleanup by making some Context members private

* Add events (from dependencies and exported) and callbacks to the mod symbol format and add support to them in elf parsing

* Add runtime-driven fields to offline mod recompiler, fix event symbol relocs using the wrong section in the mod tool

* Move file header writing outside of function recompilation

* Allow cross-section relocations, encode exact target section in mod relocations, add way to tag reference symbol relocations

* Add local symbol addresses array to offline mod recompiler output and rename original one to reference section addresses

* Add more comments to the offline mod recompiler's output

* Fix handling of section load addresses to match objcopy behavior, added event parsing to dependency tomls, minor cleanup

* Fixed incorrect size used for finding section segments

* Add missing includes for libstdc++

* Rework callbacks and imports to use the section name for identifying the dependency instead of relying on per-dependency tomls
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Wiseguy 2024-08-26 23:06:34 -04:00 • committed by GitHub
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#include <optional>
#include "fmt/format.h"
// #include "fmt/ostream.h"
#include "n64recomp.h"
#include "elfio/elfio.hpp"
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) {
bool found_entrypoint_func = false;
ELFIO::symbol_section_accessor symbols{ elf_file, symtab_section };
std::unordered_map<uint16_t, uint16_t> bss_section_to_target_section{};
// Create a mapping of bss section to the corresponding non-bss section. This is only used when dumping context in order
// for patches and mods to correctly relocate symbols in bss. This mapping only matters for relocatable sections.
if (dumping_context) {
// Process bss and reloc sections
for (size_t cur_section_index = 0; cur_section_index < context.sections.size(); cur_section_index++) {
const N64Recomp::Section& cur_section = context.sections[cur_section_index];
// Check if a bss section was found that corresponds with this section.
if (cur_section.bss_section_index != (uint16_t)-1) {
bss_section_to_target_section[cur_section.bss_section_index] = cur_section_index;
}
}
}
for (int sym_index = 0; sym_index < symbols.get_symbols_num(); sym_index++) {
std::string name;
ELFIO::Elf64_Addr value;
ELFIO::Elf_Xword size;
unsigned char bind;
unsigned char type;
ELFIO::Elf_Half section_index;
unsigned char other;
bool ignored = false;
bool reimplemented = false;
bool recorded_symbol = false;
// Read symbol properties
symbols.get_symbol(sym_index, name, value, size, bind, type,
section_index, other);
if (section_index == ELFIO::SHN_ABS && elf_config.use_absolute_symbols) {
uint32_t vram = static_cast<uint32_t>(value);
context.functions_by_vram[vram].push_back(context.functions.size());
context.functions.emplace_back(
vram,
0,
std::vector<uint32_t>{},
std::move(name),
0,
true,
reimplemented,
false
);
continue;
}
if (section_index < context.sections.size()) {
// Check if this symbol is the entrypoint
if (elf_config.has_entrypoint && value == elf_config.entrypoint_address && type == ELFIO::STT_FUNC) {
if (found_entrypoint_func) {
fmt::print(stderr, "Ambiguous entrypoint: {}\n", name);
return false;
}
found_entrypoint_func = true;
fmt::print("Found entrypoint, original name: {}\n", name);
size = 0x50; // dummy size for entrypoints, should cover them all
name = "recomp_entrypoint";
}
// Check if this symbol has a size override
auto size_find = elf_config.manually_sized_funcs.find(name);
if (size_find != elf_config.manually_sized_funcs.end()) {
size = size_find->second;
type = ELFIO::STT_FUNC;
}
if (!dumping_context) {
if (N64Recomp::reimplemented_funcs.contains(name)) {
reimplemented = true;
name = name + "_recomp";
ignored = true;
} else if (N64Recomp::ignored_funcs.contains(name)) {
name = name + "_recomp";
ignored = true;
}
}
auto& section = context.sections[section_index];
// Check if this symbol is a function or has no type (like a regular glabel would)
// Symbols with no type have a dummy entry created so that their symbol can be looked up for function calls
if (ignored || type == ELFIO::STT_FUNC || type == ELFIO::STT_NOTYPE || type == ELFIO::STT_OBJECT) {
if (!dumping_context) {
if (N64Recomp::renamed_funcs.contains(name)) {
name = name + "_recomp";
ignored = false;
}
}
if (section_index < context.sections.size()) {
auto section_offset = value - elf_file.sections[section_index]->get_address();
const uint32_t* words = reinterpret_cast<const uint32_t*>(elf_file.sections[section_index]->get_data() + section_offset);
uint32_t vram = static_cast<uint32_t>(value);
uint32_t num_instructions = type == ELFIO::STT_FUNC ? size / 4 : 0;
uint32_t rom_address = static_cast<uint32_t>(section_offset + section.rom_addr);
section.function_addrs.push_back(vram);
context.functions_by_vram[vram].push_back(context.functions.size());
// Find the entrypoint by rom address in case it doesn't have vram as its value
if (elf_config.has_entrypoint && rom_address == 0x1000 && type == ELFIO::STT_FUNC) {
vram = elf_config.entrypoint_address;
found_entrypoint_func = true;
name = "recomp_entrypoint";
if (size == 0) {
num_instructions = 0x50 / 4;
}
}
// Suffix local symbols to prevent name conflicts.
if (bind == ELFIO::STB_LOCAL) {
name = fmt::format("{}_{:08X}", name, rom_address);
}
if (num_instructions > 0) {
context.section_functions[section_index].push_back(context.functions.size());
recorded_symbol = true;
}
context.functions_by_name[name] = context.functions.size();
std::vector<uint32_t> insn_words(num_instructions);
insn_words.assign(words, words + num_instructions);
context.functions.emplace_back(
vram,
rom_address,
std::move(insn_words),
name,
section_index,
ignored,
reimplemented
);
} else {
// TODO is this case needed anymore?
uint32_t vram = static_cast<uint32_t>(value);
section.function_addrs.push_back(vram);
context.functions_by_vram[vram].push_back(context.functions.size());
context.functions.emplace_back(
vram,
0,
std::vector<uint32_t>{},
name,
section_index,
ignored,
reimplemented
);
}
}
}
// The symbol wasn't detected as a function, so add it to the data symbols if the context is being dumped.
if (!recorded_symbol && dumping_context && !name.empty()) {
uint32_t vram = static_cast<uint32_t>(value);
// Place this symbol in the absolute symbol list if it's in the absolute section.
uint16_t target_section_index = section_index;
if (section_index == ELFIO::SHN_ABS) {
target_section_index = N64Recomp::SectionAbsolute;
}
else if (section_index >= context.sections.size()) {
fmt::print("Symbol \"{}\" not in a valid section ({})\n", name, section_index);
}
// Move this symbol into the corresponding non-bss section if it's in a bss section.
auto find_bss_it = bss_section_to_target_section.find(target_section_index);
if (find_bss_it != bss_section_to_target_section.end()) {
target_section_index = find_bss_it->second;
}
data_syms[target_section_index].emplace_back(
vram,
std::move(name)
);
}
}
return found_entrypoint_func;
}
struct SegmentEntry {
ELFIO::Elf64_Off data_offset;
ELFIO::Elf64_Addr physical_address;
ELFIO::Elf_Xword memory_size;
};
std::optional<size_t> get_segment(const std::vector<SegmentEntry>& segments, ELFIO::Elf_Xword section_size, ELFIO::Elf64_Off section_offset) {
// A linear search is safest even if the segment list is sorted, as there may be overlapping segments
for (size_t i = 0; i < segments.size(); i++) {
const auto& segment = segments[i];
// Check that the section's data in the elf file is within bounds of the segment's data
if (section_offset >= segment.data_offset && section_offset + section_size <= segment.data_offset + segment.memory_size) {
return i;
}
}
return std::nullopt;
}
ELFIO::section* read_sections(N64Recomp::Context& context, const N64Recomp::ElfParsingConfig& elf_config, const ELFIO::elfio& elf_file) {
ELFIO::section* symtab_section = nullptr;
std::vector<SegmentEntry> segments{};
segments.resize(elf_file.segments.size());
bool has_reference_symbols = context.has_reference_symbols();
// Copy the data for each segment into the segment entry list
for (size_t segment_index = 0; segment_index < elf_file.segments.size(); segment_index++) {
const auto& segment = *elf_file.segments[segment_index];
segments[segment_index].data_offset = segment.get_offset();
segments[segment_index].physical_address = segment.get_physical_address();
segments[segment_index].memory_size = segment.get_file_size();
}
//// Sort the segments by physical address
//std::sort(segments.begin(), segments.end(),
// [](const SegmentEntry& lhs, const SegmentEntry& rhs) {
// return lhs.data_offset < rhs.data_offset;
// }
//);
std::unordered_map<std::string, ELFIO::section*> reloc_sections_by_name;
std::unordered_map<std::string, ELFIO::section*> bss_sections_by_name;
// 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.
uint32_t min_load_address = (uint32_t)-1;
for (const auto& section : elf_file.sections) {
auto& section_out = context.sections[section->get_index()];
ELFIO::Elf_Word type = section->get_type();
ELFIO::Elf_Xword flags = section->get_flags();
ELFIO::Elf_Xword section_size = section->get_size();
// 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.
if (type != ELFIO::SHT_NOBITS && (flags & ELFIO::SHF_ALLOC) && section_size != 0) {
std::optional<size_t> segment_index = get_segment(segments, section_size, section->get_offset());
if (!segment_index.has_value()) {
fmt::print(stderr, "Could not find segment that section {} belongs to!\n", section->get_name());
return nullptr;
}
const SegmentEntry& segment = segments[segment_index.value()];
// Calculate the load address of the section based on that of the segment.
// This will get modified afterwards in the next pass to offset by the minimum load address.
section_out.rom_addr = segment.physical_address + (section->get_offset() - segment.data_offset);
// Track the minimum load address.
min_load_address = std::min(min_load_address, section_out.rom_addr);
}
else {
// Otherwise mark this section as having an invalid rom address
section_out.rom_addr = (uint32_t)-1;
}
}
// Iterate over every section to record rom addresses and find the symbol table
for (const auto& section : elf_file.sections) {
auto& section_out = context.sections[section->get_index()];
//fmt::print(" {}: {} @ 0x{:08X}, 0x{:08X}\n", section->get_index(), section->get_name(), section->get_address(), context.rom.size());
// Set the rom address of this section to the current accumulated ROM size
section_out.ram_addr = section->get_address();
section_out.size = section->get_size();
ELFIO::Elf_Word type = section->get_type();
std::string section_name = section->get_name();
// Check if this section is the symbol table and record it if so
if (type == ELFIO::SHT_SYMTAB) {
symtab_section = section.get();
}
if (elf_config.all_sections_relocatable || elf_config.relocatable_sections.contains(section_name)) {
section_out.relocatable = true;
}
// Check if this section is a reloc section
if (type == ELFIO::SHT_REL) {
// If it is, determine the name of the section it relocates
if (!section_name.starts_with(".rel")) {
fmt::print(stderr, "Could not determine corresponding section for reloc section {}\n", section_name.c_str());
return nullptr;
}
// FIXME This should be using SH_INFO to create a reloc section to target section mapping instead of using the name.
std::string reloc_target_section = section_name.substr(strlen(".rel"));
// If this reloc section is for a section that has been marked as relocatable, record it in the reloc section lookup.
// Alternatively, if this recompilation uses reference symbols then record all reloc sections.
bool section_is_relocatable = elf_config.all_sections_relocatable || elf_config.relocatable_sections.contains(reloc_target_section);
if (has_reference_symbols || section_is_relocatable) {
reloc_sections_by_name[reloc_target_section] = section.get();
}
}
// If the section is bss (SHT_NOBITS) and ends with the bss suffix, add it to the bss section map
if (type == ELFIO::SHT_NOBITS && section_name.ends_with(elf_config.bss_section_suffix)) {
std::string bss_target_section = section_name.substr(0, section_name.size() - elf_config.bss_section_suffix.size());
// If this bss section is for a section that has been marked as relocatable, record it in the reloc section lookup
if (elf_config.all_sections_relocatable || elf_config.relocatable_sections.contains(bss_target_section)) {
bss_sections_by_name[bss_target_section] = section.get();
}
}
// If this section was marked as being in the ROM in the previous pass, copy it into the ROM now.
if (section_out.rom_addr != (uint32_t)-1) {
// Adjust the section's final ROM address to account for the minimum load address.
section_out.rom_addr -= min_load_address;
// Resize the output rom if needed to fit this section.
size_t required_rom_size = section_out.rom_addr + section_out.size;
if (required_rom_size > context.rom.size()) {
context.rom.resize(required_rom_size);
}
// Copy this section's data into the rom.
std::copy(section->get_data(), section->get_data() + section->get_size(), &context.rom[section_out.rom_addr]);
}
// Check if this section is marked as executable, which means it has code in it
if (section->get_flags() & ELFIO::SHF_EXECINSTR) {
section_out.executable = true;
}
section_out.name = section_name;
}
if (symtab_section == nullptr) {
fmt::print(stderr, "No symtab section found\n");
return nullptr;
}
ELFIO::symbol_section_accessor symbol_accessor{ elf_file, symtab_section };
auto num_syms = symbol_accessor.get_symbols_num();
// TODO make sure that a reloc section was found for every section marked as relocatable
// Process bss and reloc sections
for (size_t section_index = 0; section_index < context.sections.size(); section_index++) {
N64Recomp::Section& section_out = context.sections[section_index];
// Check if a bss section was found that corresponds with this section
auto bss_find = bss_sections_by_name.find(section_out.name);
if (bss_find != bss_sections_by_name.end()) {
section_out.bss_section_index = bss_find->second->get_index();
section_out.bss_size = bss_find->second->get_size();
context.bss_section_to_section[section_out.bss_section_index] = section_index;
}
// Check if this section is in the ROM and relocatable.
const ELFIO::section* elf_section = elf_file.sections[section_index];
bool in_rom = (elf_section->get_type() != ELFIO::SHT_NOBITS) && (elf_section->get_flags() & ELFIO::SHF_ALLOC);
bool is_relocatable = section_out.relocatable || context.has_reference_symbols();
if (in_rom && is_relocatable) {
// Check if a reloc section was found that corresponds with this section
auto reloc_find = reloc_sections_by_name.find(section_out.name);
if (reloc_find != reloc_sections_by_name.end()) {
// Create an accessor for the reloc section
ELFIO::relocation_section_accessor rel_accessor{ elf_file, reloc_find->second };
// Allocate space for the relocs in this section
section_out.relocs.resize(rel_accessor.get_entries_num());
// Track whether the previous reloc was a HI16 and its previous full_immediate
bool prev_hi = false;
// Track whether the previous reloc was a LO16
bool prev_lo = false;
uint32_t prev_hi_immediate = 0;
uint32_t prev_hi_symbol = std::numeric_limits<uint32_t>::max();
for (size_t i = 0; i < section_out.relocs.size(); i++) {
// Get the current reloc
ELFIO::Elf64_Addr rel_offset;
ELFIO::Elf_Word rel_symbol;
unsigned int rel_type;
ELFIO::Elf_Sxword bad_rel_addend; // Addends aren't encoded in the reloc, so ignore this one
rel_accessor.get_entry(i, rel_offset, rel_symbol, rel_type, bad_rel_addend);
N64Recomp::Reloc& reloc_out = section_out.relocs[i];
// Get the real full_immediate by extracting the immediate from the instruction
uint32_t reloc_rom_addr = section_out.rom_addr + rel_offset - section_out.ram_addr;
uint32_t reloc_rom_word = byteswap(*reinterpret_cast<const uint32_t*>(context.rom.data() + reloc_rom_addr));
//context.rom section_out.rom_addr;
reloc_out.address = rel_offset;
reloc_out.symbol_index = rel_symbol;
reloc_out.type = static_cast<N64Recomp::RelocType>(rel_type);
std::string rel_symbol_name;
ELFIO::Elf64_Addr rel_symbol_value;
ELFIO::Elf_Xword rel_symbol_size;
unsigned char rel_symbol_bind;
unsigned char rel_symbol_type;
ELFIO::Elf_Half rel_symbol_section_index;
unsigned char rel_symbol_other;
bool found_rel_symbol = symbol_accessor.get_symbol(
rel_symbol, rel_symbol_name, rel_symbol_value, rel_symbol_size, rel_symbol_bind, rel_symbol_type, rel_symbol_section_index, rel_symbol_other);
uint32_t rel_section_vram = 0;
uint32_t rel_symbol_offset = 0;
// Remap relocations from the current section's bss section to itself.
// TODO Do this for any bss section and not just the current section's bss section?
if (rel_symbol_section_index == section_out.bss_section_index) {
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;
}