mirror of
https://github.com/rui314/mold.git
synced 2024-10-05 00:57:08 +03:00
b5d7335e35
This reverts the following commits because it causes a regression. -62be1fcdb0
-a7b8da9345
-21a2d6bb6c
Fixes https://github.com/rui314/mold/issues/559
757 lines
22 KiB
C++
757 lines
22 KiB
C++
#include "mold.h"
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#include "../archive-file.h"
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#include "../cmdline.h"
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#include "../output-file.h"
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#include <cstring>
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#include <functional>
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#include <iomanip>
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#include <map>
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#include <signal.h>
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#include <sys/stat.h>
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#include <sys/types.h>
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#include <tbb/global_control.h>
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#include <tbb/parallel_for_each.h>
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#include <unistd.h>
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#include <unordered_set>
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namespace mold::elf {
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template <typename E>
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static ObjectFile<E> *new_object_file(Context<E> &ctx, MappedFile<Context<E>> *mf,
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std::string archive_name) {
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if (i64 type = ((ElfEhdr<E> *)mf->data)->e_machine; type != E::e_machine)
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Fatal(ctx) << mf->name << ": incompatible file type: " << type;
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static Counter count("parsed_objs");
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count++;
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bool in_lib = ctx.in_lib || (!archive_name.empty() && !ctx.whole_archive);
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ObjectFile<E> *file = ObjectFile<E>::create(ctx, mf, archive_name, in_lib);
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file->priority = ctx.file_priority++;
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ctx.tg.run([file, &ctx] { file->parse(ctx); });
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if (ctx.arg.trace)
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SyncOut(ctx) << "trace: " << *file;
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return file;
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}
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template <typename E>
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static ObjectFile<E> *new_lto_obj(Context<E> &ctx, MappedFile<Context<E>> *mf,
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std::string archive_name) {
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static Counter count("parsed_lto_objs");
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count++;
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if (ctx.arg.ignore_ir_file.count(mf->get_identifier()))
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return nullptr;
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ObjectFile<E> *file = read_lto_object(ctx, mf);
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file->priority = ctx.file_priority++;
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file->archive_name = archive_name;
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file->is_in_lib = ctx.in_lib || (!archive_name.empty() && !ctx.whole_archive);
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file->is_alive = !file->is_in_lib;
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ctx.has_lto_object = true;
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if (ctx.arg.trace)
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SyncOut(ctx) << "trace: " << *file;
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return file;
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}
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template <typename E>
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static SharedFile<E> *
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new_shared_file(Context<E> &ctx, MappedFile<Context<E>> *mf) {
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if (i64 type = ((ElfEhdr<E> *)mf->data)->e_machine; type != E::e_machine)
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Fatal(ctx) << mf->name << ": incompatible file type: " << type;
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SharedFile<E> *file = SharedFile<E>::create(ctx, mf);
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file->priority = ctx.file_priority++;
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ctx.tg.run([file, &ctx] { file->parse(ctx); });
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if (ctx.arg.trace)
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SyncOut(ctx) << "trace: " << *file;
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return file;
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}
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template <typename E>
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void read_file(Context<E> &ctx, MappedFile<Context<E>> *mf) {
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if (ctx.visited.contains(mf->name))
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return;
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FileType type = get_file_type(mf);
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switch (type) {
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case FileType::ELF_OBJ:
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ctx.objs.push_back(new_object_file(ctx, mf, ""));
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return;
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case FileType::ELF_DSO:
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ctx.dsos.push_back(new_shared_file(ctx, mf));
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ctx.visited.insert(mf->name);
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return;
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case FileType::AR:
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case FileType::THIN_AR:
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for (MappedFile<Context<E>> *child : read_archive_members(ctx, mf)) {
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switch (get_file_type(child)) {
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case FileType::ELF_OBJ:
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ctx.objs.push_back(new_object_file(ctx, child, mf->name));
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break;
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case FileType::GCC_LTO_OBJ:
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case FileType::LLVM_BITCODE:
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if (ObjectFile<E> *file = new_lto_obj(ctx, child, mf->name))
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ctx.objs.push_back(file);
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break;
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default:
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break;
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}
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}
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ctx.visited.insert(mf->name);
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return;
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case FileType::TEXT:
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parse_linker_script(ctx, mf);
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return;
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case FileType::GCC_LTO_OBJ:
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case FileType::LLVM_BITCODE:
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if (ObjectFile<E> *file = new_lto_obj(ctx, mf, ""))
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ctx.objs.push_back(file);
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return;
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default:
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Fatal(ctx) << mf->name << ": unknown file type: " << type;
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}
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}
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// Read the beginning of a given file and returns its machine type
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// (e.g. EM_X86_64 or EM_386). Return -1 if unknown.
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template <typename E>
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static i64 get_machine_type(Context<E> &ctx, MappedFile<Context<E>> *mf) {
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switch (get_file_type(mf)) {
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case FileType::ELF_OBJ:
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case FileType::ELF_DSO:
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case FileType::GCC_LTO_OBJ:
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return ((ElfEhdr<E> *)mf->data)->e_machine;
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case FileType::AR:
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for (MappedFile<Context<E>> *child : read_fat_archive_members(ctx, mf))
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if (get_file_type(child) == FileType::ELF_OBJ)
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return ((ElfEhdr<E> *)child->data)->e_machine;
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return -1;
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case FileType::THIN_AR:
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for (MappedFile<Context<E>> *child : read_thin_archive_members(ctx, mf))
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if (get_file_type(child) == FileType::ELF_OBJ)
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return ((ElfEhdr<E> *)child->data)->e_machine;
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return -1;
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case FileType::TEXT:
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return get_script_output_type(ctx, mf);
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default:
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return -1;
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}
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}
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template <typename E>
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static i64
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deduce_machine_type(Context<E> &ctx, std::span<std::string> args) {
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for (std::string_view arg : args)
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if (!arg.starts_with('-'))
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if (auto *mf = MappedFile<Context<E>>::open(ctx, std::string(arg)))
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if (i64 type = get_machine_type(ctx, mf); type != -1)
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return type;
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Fatal(ctx) << "-m option is missing";
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}
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template <typename E>
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MappedFile<Context<E>> *open_library(Context<E> &ctx, std::string path) {
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MappedFile<Context<E>> *mf = MappedFile<Context<E>>::open(ctx, path);
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if (!mf)
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return nullptr;
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i64 type = get_machine_type(ctx, mf);
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if (type == -1 || type == E::e_machine)
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return mf;
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Warn(ctx) << path << ": skipping incompatible file " << (int)type
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<< " " << (int)E::e_machine;
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return nullptr;
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}
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template <typename E>
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MappedFile<Context<E>> *find_library(Context<E> &ctx, std::string name) {
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if (name.starts_with(':')) {
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for (std::string_view dir : ctx.arg.library_paths) {
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std::string path = std::string(dir) + "/" + name.substr(1);
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if (MappedFile<Context<E>> *mf = open_library(ctx, path))
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return mf;
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}
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Fatal(ctx) << "library not found: " << name;
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}
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for (std::string_view dir : ctx.arg.library_paths) {
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std::string stem = std::string(dir) + "/lib" + name;
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if (!ctx.is_static)
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if (MappedFile<Context<E>> *mf = open_library(ctx, stem + ".so"))
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return mf;
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if (MappedFile<Context<E>> *mf = open_library(ctx, stem + ".a"))
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return mf;
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}
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Fatal(ctx) << "library not found: " << name;
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}
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template <typename E>
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static void read_input_files(Context<E> &ctx, std::span<std::string> args) {
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Timer t(ctx, "read_input_files");
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std::vector<std::tuple<bool, bool, bool, bool>> state;
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ctx.is_static = ctx.arg.is_static;
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while (!args.empty()) {
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const std::string &arg = args[0];
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args = args.subspan(1);
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if (arg == "--as-needed") {
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ctx.as_needed = true;
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} else if (arg == "--no-as-needed") {
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ctx.as_needed = false;
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} else if (arg == "--whole-archive") {
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ctx.whole_archive = true;
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} else if (arg == "--no-whole-archive") {
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ctx.whole_archive = false;
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} else if (arg == "--Bstatic") {
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ctx.is_static = true;
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} else if (arg == "--Bdynamic") {
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ctx.is_static = false;
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} else if (arg == "--start-lib") {
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ctx.in_lib = true;
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} else if (arg == "--end-lib") {
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ctx.in_lib = false;
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} else if (arg.starts_with("--version-script=")) {
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parse_version_script(ctx, arg.substr(strlen("--version-script=")));
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} else if (arg.starts_with("--dynamic-list=")) {
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parse_dynamic_list(ctx, arg.substr(strlen("--dynamic-list=")));
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} else if (arg == "--push-state") {
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state.push_back({ctx.as_needed, ctx.whole_archive, ctx.is_static,
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ctx.in_lib});
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} else if (arg == "--pop-state") {
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if (state.empty())
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Fatal(ctx) << "no state pushed before popping";
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std::tie(ctx.as_needed, ctx.whole_archive, ctx.is_static, ctx.in_lib) =
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state.back();
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state.pop_back();
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} else if (arg.starts_with("-l")) {
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MappedFile<Context<E>> *mf = find_library(ctx, arg.substr(2));
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mf->given_fullpath = false;
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read_file(ctx, mf);
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} else {
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read_file(ctx, MappedFile<Context<E>>::must_open(ctx, std::string(arg)));
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}
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}
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if (ctx.objs.empty())
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Fatal(ctx) << "no input files";
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ctx.tg.wait();
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}
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template <typename E>
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static i64 get_mtime(Context<E> &ctx, std::string path) {
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struct stat st;
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if (stat(path.c_str(), &st) < 0)
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Fatal(ctx) << path << ": stat failed: " << errno_string();
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return st.st_mtime;
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}
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template <typename E>
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static bool reload_input_files(Context<E> &ctx) {
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Timer t(ctx, "reload_input_files");
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std::vector<ObjectFile<E> *> objs;
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std::vector<SharedFile<E> *> dsos;
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// Reload updated .o files
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for (ObjectFile<E> *file : ctx.objs) {
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if (file->mf->parent) {
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if (get_mtime(ctx, file->mf->parent->name) != file->mf->parent->mtime)
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return false;
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objs.push_back(file);
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continue;
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}
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if (get_mtime(ctx, file->mf->name) == file->mf->mtime) {
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objs.push_back(file);
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continue;
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}
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MappedFile<Context<E>> *mf =
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MappedFile<Context<E>>::must_open(ctx, file->mf->name);
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objs.push_back(new_object_file(ctx, mf, file->mf->name));
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}
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// Reload updated .so files
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for (SharedFile<E> *file : ctx.dsos) {
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if (get_mtime(ctx, file->mf->name) == file->mf->mtime) {
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dsos.push_back(file);
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} else {
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MappedFile<Context<E>> *mf =
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MappedFile<Context<E>>::must_open(ctx, file->mf->name);
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dsos.push_back(new_shared_file(ctx, mf));
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}
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}
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ctx.objs = objs;
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ctx.dsos = dsos;
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return true;
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}
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template <typename E>
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static void show_stats(Context<E> &ctx) {
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for (ObjectFile<E> *obj : ctx.objs) {
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static Counter defined("defined_syms");
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defined += obj->first_global - 1;
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static Counter undefined("undefined_syms");
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undefined += obj->symbols.size() - obj->first_global;
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for (std::unique_ptr<InputSection<E>> &sec : obj->sections) {
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if (!sec || !sec->is_alive)
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continue;
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static Counter alloc("reloc_alloc");
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static Counter nonalloc("reloc_nonalloc");
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if (sec->shdr().sh_flags & SHF_ALLOC)
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alloc += sec->get_rels(ctx).size();
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else
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nonalloc += sec->get_rels(ctx).size();
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}
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static Counter comdats("comdats");
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comdats += obj->comdat_groups.size();
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static Counter removed_comdats("removed_comdat_mem");
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for (auto &pair : obj->comdat_groups)
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if (ComdatGroup *group = pair.first; group->owner != obj->priority)
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removed_comdats += pair.second.size();
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static Counter num_cies("num_cies");
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num_cies += obj->cies.size();
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static Counter num_unique_cies("num_unique_cies");
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for (CieRecord<E> &cie : obj->cies)
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if (cie.is_leader)
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num_unique_cies++;
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static Counter num_fdes("num_fdes");
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num_fdes += obj->fdes.size();
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}
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static Counter num_bytes("total_input_bytes");
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for (std::unique_ptr<MappedFile<Context<E>>> &mf : ctx.mf_pool)
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num_bytes += mf->size;
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static Counter num_input_sections("input_sections");
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for (ObjectFile<E> *file : ctx.objs)
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num_input_sections += file->sections.size();
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static Counter num_output_chunks("output_chunks", ctx.chunks.size());
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static Counter num_objs("num_objs", ctx.objs.size());
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static Counter num_dsos("num_dsos", ctx.dsos.size());
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if constexpr (std::is_same_v<E, ARM64>) {
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static Counter num_thunks("num_thunks");
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for (std::unique_ptr<OutputSection<E>> &osec : ctx.output_sections)
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for (std::unique_ptr<RangeExtensionThunk<E>> &thunk : osec->thunks)
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num_thunks += thunk->symbols.size();
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}
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Counter::print();
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for (std::unique_ptr<MergedSection<E>> &sec : ctx.merged_sections)
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sec->print_stats(ctx);
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}
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template <typename E>
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static int elf_main(int argc, char **argv) {
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Context<E> ctx;
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// Process -run option first. process_run_subcommand() does not return.
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if (argc >= 2)
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if (argv[1] == "-run"sv || argv[1] == "--run"sv)
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process_run_subcommand(ctx, argc, argv);
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// Parse non-positional command line options
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ctx.cmdline_args = expand_response_files(ctx, argv);
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std::vector<std::string> file_args = parse_nonpositional_args(ctx);
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// If no -m option is given, deduce it from input files.
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if (ctx.arg.emulation == -1)
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ctx.arg.emulation = deduce_machine_type(ctx, file_args);
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// Redo if -m is not x86-64.
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if (ctx.arg.emulation != E::e_machine) {
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#if !MOLD_DEBUG_X86_64_ONLY && !MOLD_DEBUG_ARM64_ONLY
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switch (ctx.arg.emulation) {
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case EM_386:
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return elf_main<I386>(argc, argv);
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case EM_AARCH64:
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return elf_main<ARM64>(argc, argv);
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case EM_ARM:
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return elf_main<ARM32>(argc, argv);
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case EM_RISCV:
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return elf_main<RISCV64>(argc, argv);
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}
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#endif
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Fatal(ctx) << "unknown emulation: " << ctx.arg.emulation;
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}
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Timer t_all(ctx, "all");
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install_signal_handler();
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if (!ctx.arg.directory.empty())
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if (chdir(ctx.arg.directory.c_str()) == -1)
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Fatal(ctx) << "chdir failed: " << ctx.arg.directory
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<< ": " << errno_string();
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if (ctx.arg.relocatable) {
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combine_objects(ctx, file_args);
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return 0;
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}
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// Fork a subprocess unless --no-fork is given.
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std::function<void()> on_complete;
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if (ctx.arg.fork)
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on_complete = fork_child();
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tbb::global_control tbb_cont(tbb::global_control::max_allowed_parallelism,
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ctx.arg.thread_count);
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// Handle --wrap options if any.
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for (std::string_view name : ctx.arg.wrap)
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get_symbol(ctx, name)->wrap = true;
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// Handle --retain-symbols-file options if any.
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if (ctx.arg.retain_symbols_file)
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for (std::string_view name : *ctx.arg.retain_symbols_file)
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get_symbol(ctx, name)->write_to_symtab = true;
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for (std::string_view arg : ctx.arg.trace_symbol)
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get_symbol(ctx, arg)->traced = true;
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// Parse input files
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read_input_files(ctx, file_args);
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// Uniquify shared object files by soname
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{
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std::unordered_set<std::string_view> seen;
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std::erase_if(ctx.dsos, [&](SharedFile<E> *file) {
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return !seen.insert(file->soname).second;
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});
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}
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Timer t_total(ctx, "total");
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Timer t_before_copy(ctx, "before_copy");
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// Apply -exclude-libs
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apply_exclude_libs(ctx);
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// Resolve symbols and fix the set of object files that are
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// included to the final output.
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resolve_symbols(ctx);
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// Resolve mergeable section pieces to merge them.
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register_section_pieces(ctx);
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// Remove redundant comdat sections (e.g. duplicate inline functions).
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eliminate_comdats(ctx);
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// Create .bss sections for common symbols.
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convert_common_symbols(ctx);
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// Apply version scripts.
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apply_version_script(ctx);
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// Parse symbol version suffixes (e.g. "foo@ver1").
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parse_symbol_version(ctx);
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// Set is_import and is_export bits for each symbol.
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compute_import_export(ctx);
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// Read address-significant section information.
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|
if (ctx.arg.icf && !ctx.arg.icf_all)
|
|
mark_addrsig(ctx);
|
|
|
|
// Garbage-collect unreachable sections.
|
|
if (ctx.arg.gc_sections)
|
|
gc_sections(ctx);
|
|
|
|
// Merge identical read-only sections.
|
|
if (ctx.arg.icf)
|
|
icf_sections(ctx);
|
|
|
|
// Compute sizes of sections containing mergeable strings.
|
|
compute_merged_section_sizes(ctx);
|
|
|
|
// Create instances of linker-synthesized sections such as
|
|
// .got or .plt.
|
|
create_synthetic_sections(ctx);
|
|
|
|
// Bin input sections into output sections.
|
|
bin_sections(ctx);
|
|
|
|
// Get a list of output sections.
|
|
append(ctx.chunks, collect_output_sections(ctx));
|
|
|
|
// Create a dummy file containing linker-synthesized symbols
|
|
// (e.g. `__bss_start`).
|
|
ctx.internal_obj = create_internal_file(ctx);
|
|
ctx.objs.push_back(ctx.internal_obj);
|
|
|
|
// Beyond this point, no new files will be added to ctx.objs
|
|
// or ctx.dsos.
|
|
|
|
// Handle `-z cet-report`.
|
|
if (ctx.arg.z_cet_report != CET_REPORT_NONE)
|
|
check_cet_errors(ctx);
|
|
|
|
// Handle `-z execstack-if-needed`.
|
|
if (ctx.arg.z_execstack_if_needed)
|
|
for (ObjectFile<E> *file : ctx.objs)
|
|
if (file->needs_executable_stack)
|
|
ctx.arg.z_execstack = true;
|
|
|
|
// If we are linking a .so file, remaining undefined symbols does
|
|
// not cause a linker error. Instead, they are treated as if they
|
|
// were imported symbols.
|
|
//
|
|
// If we are linking an executable, weak undefs are converted to
|
|
// weakly imported symbol so that they'll have another chance to be
|
|
// resolved.
|
|
claim_unresolved_symbols(ctx);
|
|
|
|
// Beyond this point, no new symbols will be added to the result.
|
|
|
|
// Handle --print-dependencies
|
|
if (ctx.arg.print_dependencies == 1)
|
|
print_dependencies(ctx);
|
|
else if (ctx.arg.print_dependencies == 2)
|
|
print_dependencies_full(ctx);
|
|
|
|
// Handle -repro
|
|
if (ctx.arg.repro)
|
|
write_repro_file(ctx);
|
|
|
|
// Make sure that all symbols have been resolved.
|
|
if (!ctx.arg.allow_multiple_definition)
|
|
check_duplicate_symbols(ctx);
|
|
|
|
// Handle --require-defined
|
|
for (std::string_view name : ctx.arg.require_defined)
|
|
if (!get_symbol(ctx, name)->file)
|
|
Error(ctx) << "--require-defined: undefined symbol: " << name;
|
|
|
|
// .init_array and .fini_array contents have to be sorted by
|
|
// a special rule. Sort them.
|
|
sort_init_fini(ctx);
|
|
|
|
// Likewise, .ctors and .dtors have to be sorted. They are rare
|
|
// because they are superceded by .init_array/.fini_array, though.
|
|
sort_ctor_dtor(ctx);
|
|
|
|
// Handle --shuffle-sections
|
|
if (ctx.arg.shuffle_sections != SHUFFLE_SECTIONS_NONE)
|
|
shuffle_sections(ctx);
|
|
|
|
// Copy string referred by .dynamic to .dynstr.
|
|
for (SharedFile<E> *file : ctx.dsos)
|
|
ctx.dynstr->add_string(file->soname);
|
|
for (std::string_view str : ctx.arg.auxiliary)
|
|
ctx.dynstr->add_string(str);
|
|
for (std::string_view str : ctx.arg.filter)
|
|
ctx.dynstr->add_string(str);
|
|
if (!ctx.arg.rpaths.empty())
|
|
ctx.dynstr->add_string(ctx.arg.rpaths);
|
|
if (!ctx.arg.soname.empty())
|
|
ctx.dynstr->add_string(ctx.arg.soname);
|
|
|
|
// Scan relocations to find symbols that need entries in .got, .plt,
|
|
// .got.plt, .dynsym, .dynstr, etc.
|
|
scan_rels(ctx);
|
|
|
|
// Compute sizes of output sections while assigning offsets
|
|
// within an output section to input sections.
|
|
compute_section_sizes(ctx);
|
|
|
|
// Sort sections by section attributes so that we'll have to
|
|
// create as few segments as possible.
|
|
sort(ctx.chunks, [&](Chunk<E> *a, Chunk<E> *b) {
|
|
return get_section_rank(ctx, a) < get_section_rank(ctx, b);
|
|
});
|
|
|
|
// If --packed_dyn_relocs=relr was given, base relocations are stored
|
|
// to a .relr.dyn section in a compressed form. Construct a compressed
|
|
// relocations now so that we can fix section sizes and file layout.
|
|
if (ctx.arg.pack_dyn_relocs_relr)
|
|
construct_relr(ctx);
|
|
|
|
// Reserve a space for dynamic symbol strings in .dynstr and sort
|
|
// .dynsym contents if necessary. Beyond this point, no symbol will
|
|
// be added to .dynsym.
|
|
ctx.dynsym->finalize(ctx);
|
|
|
|
// Print reports about undefined symbols, if needed.
|
|
if (ctx.arg.unresolved_symbols == UNRESOLVED_ERROR)
|
|
report_undef_errors(ctx);
|
|
|
|
// Fill .gnu.version_d section contents.
|
|
if (ctx.verdef)
|
|
ctx.verdef->construct(ctx);
|
|
|
|
// Fill .gnu.version_r section contents.
|
|
ctx.verneed->construct(ctx);
|
|
|
|
// Compute .symtab and .strtab sizes for each file.
|
|
create_output_symtab(ctx);
|
|
|
|
// .eh_frame is a special section from the linker's point of view,
|
|
// as its contents are parsed and reconstructed by the linker,
|
|
// unlike other sections that are regarded as opaque bytes.
|
|
// Here, we construct output .eh_frame contents.
|
|
ctx.eh_frame->construct(ctx);
|
|
|
|
// Handle --gdb-index.
|
|
if (ctx.arg.gdb_index)
|
|
ctx.gdb_index->construct(ctx);
|
|
|
|
// If --emit-relocs is given, we'll copy relocation sections from input
|
|
// files to an output file.
|
|
if (ctx.arg.emit_relocs)
|
|
create_reloc_sections(ctx);
|
|
|
|
// Update sh_size for each chunk and remove empty ones.
|
|
for (Chunk<E> *chunk : ctx.chunks)
|
|
chunk->update_shdr(ctx);
|
|
|
|
std::erase_if(ctx.chunks, [](Chunk<E> *chunk) {
|
|
return chunk->kind() != OUTPUT_SECTION && chunk->shdr.sh_size == 0;
|
|
});
|
|
|
|
// Set section indices.
|
|
for (i64 i = 0, shndx = 1; i < ctx.chunks.size(); i++)
|
|
if (ctx.chunks[i]->kind() != HEADER)
|
|
ctx.chunks[i]->shndx = shndx++;
|
|
|
|
// Some types of section header refer other section by index.
|
|
// Recompute the section header to fill such fields with correct values.
|
|
for (Chunk<E> *chunk : ctx.chunks)
|
|
chunk->update_shdr(ctx);
|
|
|
|
// Assign offsets to output sections
|
|
i64 filesize = set_osec_offsets(ctx);
|
|
|
|
// On RISC-V, branches are encode using multiple instructions so
|
|
// that they can jump to anywhere in ±2 GiB by default. They may
|
|
// be replaced with shorter instruction sequences if destinations
|
|
// are close enough. Do this optimization.
|
|
if constexpr (std::is_same_v<E, RISCV64>)
|
|
filesize = riscv_resize_sections(ctx);
|
|
|
|
// Fix linker-synthesized symbol addresses.
|
|
fix_synthetic_symbols(ctx);
|
|
|
|
// Beyond this, you can assume that symbol addresses including their
|
|
// GOT or PLT addresses have a correct final value.
|
|
|
|
// If --compress-debug-sections is given, compress .debug_* sections
|
|
// using zlib.
|
|
if (ctx.arg.compress_debug_sections != COMPRESS_NONE)
|
|
filesize = compress_debug_sections(ctx);
|
|
|
|
// At this point, file layout is fixed.
|
|
|
|
t_before_copy.stop();
|
|
|
|
// Create an output file
|
|
ctx.output_file =
|
|
OutputFile<Context<E>>::open(ctx, ctx.arg.output, filesize, 0777);
|
|
ctx.buf = ctx.output_file->buf;
|
|
|
|
Timer t_copy(ctx, "copy");
|
|
|
|
// Copy input sections to the output file
|
|
{
|
|
Timer t(ctx, "copy_buf");
|
|
|
|
tbb::parallel_for_each(ctx.chunks, [&](Chunk<E> *chunk) {
|
|
std::string name =
|
|
chunk->name.empty() ? "(header)" : std::string(chunk->name);
|
|
Timer t2(ctx, name, &t);
|
|
chunk->copy_buf(ctx);
|
|
});
|
|
|
|
report_undef_errors(ctx);
|
|
}
|
|
|
|
if constexpr (std::is_same_v<E, ARM32>)
|
|
sort_arm_exidx(ctx);
|
|
|
|
// Some part of .gdb_index couldn't be computed until other debug
|
|
// sections are complete. We have complete debug sections now, so
|
|
// write the rest of .gdb_index.
|
|
if (ctx.gdb_index)
|
|
ctx.gdb_index->write_address_areas(ctx);
|
|
|
|
// Dynamic linker works better with sorted .rela.dyn section,
|
|
// so we sort them.
|
|
ctx.reldyn->sort(ctx);
|
|
|
|
// Zero-clear paddings between sections
|
|
clear_padding(ctx);
|
|
|
|
if (ctx.buildid)
|
|
ctx.buildid->write_buildid(ctx);
|
|
|
|
t_copy.stop();
|
|
ctx.checkpoint();
|
|
|
|
// Close the output file. This is the end of the linker's main job.
|
|
ctx.output_file->close(ctx);
|
|
|
|
// Handle --dependency-file
|
|
if (!ctx.arg.dependency_file.empty())
|
|
write_dependency_file(ctx);
|
|
|
|
if (ctx.has_lto_object)
|
|
lto_cleanup(ctx);
|
|
|
|
t_total.stop();
|
|
t_all.stop();
|
|
|
|
if (ctx.arg.print_map)
|
|
print_map(ctx);
|
|
|
|
// Show stats numbers
|
|
if (ctx.arg.stats)
|
|
show_stats(ctx);
|
|
|
|
if (ctx.arg.perf)
|
|
print_timer_records(ctx.timer_records);
|
|
|
|
std::cout << std::flush;
|
|
std::cerr << std::flush;
|
|
if (on_complete)
|
|
on_complete();
|
|
|
|
if (ctx.arg.quick_exit)
|
|
_exit(0);
|
|
|
|
for (std::function<void()> &fn : ctx.on_exit)
|
|
fn();
|
|
ctx.checkpoint();
|
|
return 0;
|
|
}
|
|
|
|
int main(int argc, char **argv) {
|
|
#if MOLD_DEBUG_ARM64_ONLY
|
|
return elf_main<ARM64>(argc, argv);
|
|
#else
|
|
return elf_main<X86_64>(argc, argv);
|
|
#endif
|
|
}
|
|
|
|
#define INSTANTIATE(E) \
|
|
template void read_file(Context<E> &, MappedFile<Context<E>> *);
|
|
|
|
INSTANTIATE_ALL;
|
|
|
|
} // namespace mold::elf
|