mirror of
https://github.com/rui314/mold.git
synced 2024-12-28 19:04:27 +03:00
727 lines
22 KiB
C++
727 lines
22 KiB
C++
#include "mold.h"
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#include <limits>
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#include <zlib.h>
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static u64 read64be(u8 *buf) {
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return ((u64)buf[0] << 56) | ((u64)buf[1] << 48) |
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((u64)buf[2] << 40) | ((u64)buf[3] << 32) |
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((u64)buf[4] << 24) | ((u64)buf[5] << 16) |
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((u64)buf[6] << 8) | (u64)buf[7];
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}
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InputSection::InputSection(ObjectFile &file, const ElfShdr &shdr,
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std::string_view name, i64 section_idx,
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std::string_view contents,
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OutputSection *osec)
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: file(file), shdr(shdr), name(name), section_idx(section_idx),
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contents(contents), output_section(osec) {}
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InputSection *InputSection::create(ObjectFile &file, const ElfShdr *shdr,
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std::string_view name, i64 section_idx) {
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std::string_view contents;
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auto do_uncompress = [&](std::string_view data, u64 size) {
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u8 *buf = new u8[size];
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unsigned long size2 = size;
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if (uncompress(buf, &size2, (u8 *)&data[0], data.size()) != Z_OK)
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Fatal() << name << ": uncompress failed";
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if (size != size2)
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Fatal() << name << ": uncompress: invalid size";
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contents = {(char *)buf, size};
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ElfShdr *shdr2 = new ElfShdr;
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*shdr2 = *shdr;
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shdr2->sh_size = size;
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shdr2->sh_flags &= ~(u64)SHF_COMPRESSED;
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shdr = shdr2;
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};
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if (name.starts_with(".zdebug")) {
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// Old-style compressed section
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std::string_view data = file.get_string(*shdr);
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if (!data.starts_with("ZLIB") || data.size() <= 12)
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Fatal() << name << ": corrupted compressed section";
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u64 size = read64be((u8 *)&data[4]);
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// Rename .zdebug -> .debug
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name = *new std::string("." + std::string(name.substr(2)));
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} else if (shdr->sh_flags & SHF_COMPRESSED) {
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// New-style compressed section
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std::string_view data = file.get_string(*shdr);
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if (data.size() < sizeof(ElfChdr))
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Fatal() << name << ": corrupted compressed section";
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ElfChdr &hdr = *(ElfChdr *)&data[0];
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if (hdr.ch_type != ELFCOMPRESS_ZLIB)
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Fatal() << name << ": unsupported compression type";
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do_uncompress(data.substr(sizeof(ElfChdr)), hdr.ch_size);
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} else if (shdr->sh_type != SHT_NOBITS) {
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contents = file.get_string(*shdr);
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}
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OutputSection *osec =
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OutputSection::get_instance(name, shdr->sh_type, shdr->sh_flags);
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return new InputSection(file, *shdr, name, section_idx, contents, osec);
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}
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static std::string rel_to_string(u64 r_type) {
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switch (r_type) {
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case R_X86_64_NONE: return "R_X86_64_NONE";
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case R_X86_64_8: return "R_X86_64_8";
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case R_X86_64_16: return "R_X86_64_16";
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case R_X86_64_32: return "R_X86_64_32";
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case R_X86_64_32S: return "R_X86_64_32S";
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case R_X86_64_64: return "R_X86_64_64";
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case R_X86_64_PC8: return "R_X86_64_PC8";
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case R_X86_64_PC16: return "R_X86_64_PC16";
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case R_X86_64_PC32: return "R_X86_64_PC32";
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case R_X86_64_PC64: return "R_X86_64_PC64";
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case R_X86_64_GOT32: return "R_X86_64_GOT32";
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case R_X86_64_GOTPC32: return "R_X86_64_GOTPC32";
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case R_X86_64_GOTPCREL: return "R_X86_64_GOTPCREL";
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case R_X86_64_GOTPCRELX: return "R_X86_64_GOTPCRELX";
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case R_X86_64_REX_GOTPCRELX: return "R_X86_64_REX_GOTPCRELX";
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case R_X86_64_PLT32: return "R_X86_64_PLT32";
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case R_X86_64_TLSGD: return "R_X86_64_TLSGD";
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case R_X86_64_TLSLD: return "R_X86_64_TLSLD";
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case R_X86_64_TPOFF32: return "R_X86_64_TPOFF32";
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case R_X86_64_DTPOFF32: return "R_X86_64_DTPOFF32";
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case R_X86_64_TPOFF64: return "R_X86_64_TPOFF64";
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case R_X86_64_DTPOFF64: return "R_X86_64_DTPOFF64";
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case R_X86_64_GOTTPOFF: return "R_X86_64_GOTTPOFF";
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}
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unreachable();
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}
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__attribute__((always_inline))
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static void overflow_check(InputSection *sec, Symbol &sym, u64 r_type, u64 val) {
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switch (r_type) {
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case R_X86_64_8:
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if (val != (u8)val)
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Error() << *sec << ": relocation R_X86_64_8 against " << sym
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<< " out of range: " << val << " is not in [0, 255]";
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return;
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case R_X86_64_PC8:
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if (val != (i8)val)
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Error() << *sec << ": relocation R_X86_64_PC8 against " << sym
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<< " out of range: " << (i64)val << " is not in [-128, 127]";
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return;
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case R_X86_64_16:
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if (val != (u16)val)
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Error() << *sec << ": relocation R_X86_64_16 against " << sym
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<< " out of range: " << val << " is not in [0, 65535]";
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return;
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case R_X86_64_PC16:
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if (val != (i16)val)
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Error() << *sec << ": relocation R_X86_64_PC16 against " << sym
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<< " out of range: " << (i64)val << " is not in [-32768, 32767]";
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return;
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case R_X86_64_32:
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if (val != (u32)val)
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Error() << *sec << ": relocation R_X86_64_32 against " << sym
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<< " out of range: " << val << " is not in [0, 4294967296]";
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return;
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case R_X86_64_32S:
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case R_X86_64_PC32:
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case R_X86_64_GOT32:
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case R_X86_64_GOTPC32:
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case R_X86_64_GOTPCREL:
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case R_X86_64_GOTPCRELX:
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case R_X86_64_REX_GOTPCRELX:
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case R_X86_64_PLT32:
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case R_X86_64_TLSGD:
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case R_X86_64_TLSLD:
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case R_X86_64_TPOFF32:
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case R_X86_64_DTPOFF32:
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case R_X86_64_GOTTPOFF:
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case R_X86_64_GOTPC32_TLSDESC:
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case R_X86_64_TLSDESC_CALL:
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if (val != (i32)val)
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Error() << *sec << ": relocation " << rel_to_string(r_type)
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<< " against " << sym << " out of range: " << (i64)val
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<< " is not in [-2147483648, 2147483647]";
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return;
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case R_X86_64_NONE:
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case R_X86_64_64:
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case R_X86_64_PC64:
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case R_X86_64_TPOFF64:
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case R_X86_64_DTPOFF64:
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return;
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}
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unreachable();
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}
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__attribute__((always_inline))
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static void write_val(u64 r_type, u8 *loc, u64 val) {
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switch (r_type) {
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case R_X86_64_NONE:
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return;
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case R_X86_64_8:
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case R_X86_64_PC8:
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*loc = val;
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return;
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case R_X86_64_16:
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case R_X86_64_PC16:
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*(u16 *)loc = val;
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return;
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case R_X86_64_32:
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case R_X86_64_32S:
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case R_X86_64_PC32:
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case R_X86_64_GOT32:
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case R_X86_64_GOTPC32:
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case R_X86_64_GOTPCREL:
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case R_X86_64_GOTPCRELX:
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case R_X86_64_REX_GOTPCRELX:
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case R_X86_64_PLT32:
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case R_X86_64_TLSGD:
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case R_X86_64_TLSLD:
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case R_X86_64_TPOFF32:
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case R_X86_64_DTPOFF32:
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case R_X86_64_GOTTPOFF:
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case R_X86_64_GOTPC32_TLSDESC:
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case R_X86_64_TLSDESC_CALL:
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*(u32 *)loc = val;
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return;
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case R_X86_64_64:
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case R_X86_64_PC64:
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case R_X86_64_TPOFF64:
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case R_X86_64_DTPOFF64:
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*(u64 *)loc = val;
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return;
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}
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unreachable();
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}
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void InputSection::copy_buf() {
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if (shdr.sh_type == SHT_NOBITS || shdr.sh_size == 0)
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return;
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// Copy data
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u8 *base = out::buf + output_section->shdr.sh_offset + offset;
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memcpy(base, contents.data(), contents.size());
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// Apply relocations
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if (shdr.sh_flags & SHF_ALLOC)
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apply_reloc_alloc(base);
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else
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apply_reloc_nonalloc(base);
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}
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static u32 get_gottpoff_relaxed_insn(u8 *insn) {
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// We want to rewrite `mov x@gottpoff(%rip),%r64` to `mov x@tpoff,%r64`.
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switch ((insn[0] << 16) | (insn[1] << 8) | insn[2]) {
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case 0x488b05: return 0x48c7c0; // mov x@gottpoff(%rip), %rax
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case 0x488b0d: return 0x48c7c1; // mov x@gottpoff(%rip), %rcx
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case 0x488b15: return 0x48c7c2; // mov x@gottpoff(%rip), %rdx
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case 0x488b1d: return 0x48c7c3; // mov x@gottpoff(%rip), %rbx
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case 0x488b25: return 0x48c7c4; // mov x@gottpoff(%rip), %rsp
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case 0x488b2d: return 0x48c7c5; // mov x@gottpoff(%rip), %rbp
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case 0x488b35: return 0x48c7c6; // mov x@gottpoff(%rip), %rsi
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case 0x488b3d: return 0x48c7c7; // mov x@gottpoff(%rip), %rdi
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case 0x4c8b05: return 0x49c7c0; // mov x@gottpoff(%rip), %r8
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case 0x4c8b0d: return 0x49c7c1; // mov x@gottpoff(%rip), %r9
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case 0x4c8b15: return 0x49c7c2; // mov x@gottpoff(%rip), %r10
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case 0x4c8b1d: return 0x49c7c3; // mov x@gottpoff(%rip), %r11
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case 0x4c8b25: return 0x49c7c4; // mov x@gottpoff(%rip), %r12
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case 0x4c8b2d: return 0x49c7c5; // mov x@gottpoff(%rip), %r13
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case 0x4c8b35: return 0x49c7c6; // mov x@gottpoff(%rip), %r14
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case 0x4c8b3d: return 0x49c7c7; // mov x@gottpoff(%rip), %r15
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default:
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unreachable();
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}
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}
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// Apply relocations to SHF_ALLOC sections (i.e. sections that are
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// mapped to memory at runtime) based on the result of
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// scan_relocations().
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void InputSection::apply_reloc_alloc(u8 *base) {
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i64 ref_idx = 0;
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ElfRela *dynrel = nullptr;
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if (out::reldyn)
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dynrel = (ElfRela *)(out::buf + out::reldyn->shdr.sh_offset +
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file.reldyn_offset + this->reldyn_offset);
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for (i64 i = 0; i < rels.size(); i++) {
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const ElfRela &rel = rels[i];
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Symbol &sym = *file.symbols[rel.r_sym];
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u8 *loc = base + rel.r_offset;
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const SectionFragmentRef *ref = nullptr;
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if (has_fragments[i])
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ref = &rel_fragments[ref_idx++];
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auto write = [&](u64 val) {
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overflow_check(this, sym, rel.r_type, val);
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write_val(rel.r_type, loc, val);
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};
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#define S (ref ? ref->frag->get_addr() : sym.get_addr())
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#define A (ref ? ref->addend : rel.r_addend)
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#define P (output_section->shdr.sh_addr + offset + rel.r_offset)
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#define G (sym.get_got_addr() - out::got->shdr.sh_addr)
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#define GOT out::got->shdr.sh_addr
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switch (rel_types[i]) {
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case R_NONE:
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break;
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case R_ABS:
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write(S + A);
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break;
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case R_BASEREL:
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*dynrel++ = {P, R_X86_64_RELATIVE, 0, (i64)(S + A)};
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break;
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case R_DYN:
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*dynrel++ = {P, R_X86_64_64, sym.dynsym_idx, A};
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break;
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case R_PC:
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write(S + A - P);
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break;
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case R_GOT:
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write(G + A);
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break;
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case R_GOTPC:
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write(GOT + A - P);
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break;
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case R_GOTPCREL:
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write(G + GOT + A - P);
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break;
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case R_GOTPCREL_RELAX_CALL:
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// Rewrite indirect call to direct call.
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loc[-2] = 0x90;
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loc[-1] = 0xe8;
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write(S + A - P);
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break;
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case R_GOTPCREL_RELAX_JMP:
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// Rewrite indirect jmp to direct jmp.
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loc[-2] = 0x90;
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loc[-1] = 0xe9;
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write(S + A - P);
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break;
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case R_GOTPCREL_RELAX_MOV:
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// Rewrite mov to lea.
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loc[-2] = 0x8d;
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write(S + A - P);
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break;
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case R_TLSGD:
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write(sym.get_tlsgd_addr() + A - P);
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break;
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case R_TLSGD_RELAX_LE: {
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// Relax GD to LE
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static const u8 insn[] = {
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0x64, 0x48, 0x8b, 0x04, 0x25, 0, 0, 0, 0, // mov %fs:0, %rax
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0x48, 0x8d, 0x80, 0, 0, 0, 0, // lea x@tpoff(%rax), %rax
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};
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memcpy(loc - 4, insn, sizeof(insn));
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*(u32 *)(loc + 8) = S - out::tls_end + A + 4;
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i++;
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break;
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}
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case R_TLSLD:
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write(out::got->get_tlsld_addr() + A - P);
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break;
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case R_TLSLD_RELAX_LE: {
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// Relax LD to LE
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static const u8 insn[] = {
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// mov %fs:0, %rax
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0x66, 0x66, 0x66, 0x64, 0x48, 0x8b, 0x04, 0x25, 0, 0, 0, 0,
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};
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memcpy(loc - 3, insn, sizeof(insn));
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i++;
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break;
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}
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case R_DTPOFF:
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write(S + A - out::tls_begin);
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break;
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case R_TPOFF:
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write(S + A - out::tls_end);
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break;
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case R_GOTTPOFF:
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write(sym.get_gottpoff_addr() + A - P);
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break;
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case R_GOTTPOFF_RELAX_MOV: {
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u32 insn = get_gottpoff_relaxed_insn(loc - 3);
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loc[-3] = insn >> 16;
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loc[-2] = insn >> 8;
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loc[-1] = insn;
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write(S + A - out::tls_end + 4);
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break;
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}
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case R_GOTPC_TLSDESC:
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write(sym.get_tlsdesc_addr() + A - P);
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break;
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case R_GOTPC_TLSDESC_RELAX_LE: {
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static const u8 insn[] = {
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0x48, 0xc7, 0xc0, 0, 0, 0, 0, // mov $0, %rax
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};
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memcpy(loc - 3, insn, sizeof(insn));
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write(S + A - out::tls_end + 4);
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break;
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}
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case R_TLSDESC_CALL_RELAX:
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// Rewrite indirect call to nop.
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loc[0] = 0x66;
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loc[1] = 0x90;
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break;
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default:
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unreachable();
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}
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#undef S
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#undef A
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#undef P
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#undef G
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#undef GOT
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}
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}
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// This function is responsible for applying relocations against
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// non-SHF_ALLOC sections (i.e. sections that are not mapped to memory
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// at runtime).
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//
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// Relocations against non-SHF_ALLOC sections are much easier to
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// handle than that against SHF_ALLOC sections. It is because, since
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// they are not mapped to memory, they don't contain any variable or
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// function and never need PLT or GOT. Non-SHF_ALLOC sections are
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// mostly debug info sections.
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//
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// Relocations against non-SHF_ALLOC sections are not scanned by
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// scan_relocations.
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void InputSection::apply_reloc_nonalloc(u8 *base) {
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static Counter counter("reloc_nonalloc");
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counter += rels.size();
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i64 ref_idx = 0;
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for (i64 i = 0; i < rels.size(); i++) {
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const ElfRela &rel = rels[i];
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Symbol &sym = *file.symbols[rel.r_sym];
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u8 *loc = base + rel.r_offset;
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if (!sym.file) {
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Error() << "undefined symbol: " << file << ": " << sym;
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continue;
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}
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const SectionFragmentRef *ref = nullptr;
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if (has_fragments[i])
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ref = &rel_fragments[ref_idx++];
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switch (rel.r_type) {
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case R_X86_64_NONE:
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break;
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case R_X86_64_8:
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case R_X86_64_16:
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case R_X86_64_32:
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case R_X86_64_32S:
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case R_X86_64_64: {
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u64 val = ref ? ref->frag->get_addr() : sym.get_addr();
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overflow_check(this, sym, rel.r_type, val);
|
|
write_val(rel.r_type, loc, val);
|
|
break;
|
|
}
|
|
case R_X86_64_DTPOFF64:
|
|
write_val(rel.r_type, loc, sym.get_addr() + rel.r_addend - out::tls_begin);
|
|
break;
|
|
case R_X86_64_PC8:
|
|
case R_X86_64_PC16:
|
|
case R_X86_64_PC32:
|
|
case R_X86_64_PC64:
|
|
case R_X86_64_GOT32:
|
|
case R_X86_64_GOTPC32:
|
|
case R_X86_64_GOTPCREL:
|
|
case R_X86_64_GOTPCRELX:
|
|
case R_X86_64_REX_GOTPCRELX:
|
|
case R_X86_64_PLT32:
|
|
case R_X86_64_TLSGD:
|
|
case R_X86_64_TLSLD:
|
|
case R_X86_64_DTPOFF32:
|
|
case R_X86_64_TPOFF32:
|
|
case R_X86_64_TPOFF64:
|
|
case R_X86_64_GOTTPOFF:
|
|
Fatal() << *this << ": invalid relocation for non-allocated sections: "
|
|
<< rel.r_type;
|
|
break;
|
|
default:
|
|
Fatal() << *this << ": unknown relocation: " << rel.r_type;
|
|
}
|
|
}
|
|
}
|
|
|
|
static int get_sym_type(Symbol &sym) {
|
|
if (sym.is_absolute())
|
|
return 0;
|
|
if (!sym.is_imported)
|
|
return 1;
|
|
if (sym.get_type() != STT_FUNC)
|
|
return 2;
|
|
return 3;
|
|
}
|
|
|
|
// Returns true if the instruction is `MOV foo(%rip),%r64`.
|
|
static bool is_mov_insn(u8 *loc) {
|
|
switch ((loc[0] << 16) | (loc[1] << 8) | loc[2]) {
|
|
case 0x488b05: case 0x488b0d: case 0x488b15: case 0x488b1d:
|
|
case 0x488b25: case 0x488b2d: case 0x488b35: case 0x488b3d:
|
|
case 0x4c8b05: case 0x4c8b0d: case 0x4c8b15: case 0x4c8b1d:
|
|
case 0x4c8b25: case 0x4c8b2d: case 0x4c8b35: case 0x4c8b3d:
|
|
return true;
|
|
default:
|
|
return false;
|
|
}
|
|
}
|
|
|
|
// Linker has to create data structures in an output file to apply
|
|
// some type of relocations. For example, if a relocation refers a GOT
|
|
// or a PLT entry of a symbol, linker has to create an entry in .got
|
|
// or in .plt for that symbol. In order to fix the file layout, we
|
|
// need to scan relocations.
|
|
void InputSection::scan_relocations() {
|
|
if (!(shdr.sh_flags & SHF_ALLOC))
|
|
return;
|
|
|
|
static Counter counter("reloc_alloc");
|
|
counter += rels.size();
|
|
|
|
this->reldyn_offset = file.num_dynrel * sizeof(ElfRela);
|
|
bool is_readonly = !(shdr.sh_flags & SHF_WRITE);
|
|
i64 output_type = config.shared ? 2 : (config.pie ? 1 : 0);
|
|
|
|
// Scan relocations
|
|
for (i64 i = 0; i < rels.size(); i++) {
|
|
const ElfRela &rel = rels[i];
|
|
Symbol &sym = *file.symbols[rel.r_sym];
|
|
u8 *loc = (u8 *)(contents.data() + rel.r_offset);
|
|
|
|
if (!sym.file) {
|
|
Error() << "undefined symbol: " << file << ": " << sym;
|
|
continue;
|
|
}
|
|
|
|
typedef enum { NONE, ERROR, COPYREL, PLT, DYNREL, BASEREL } Action;
|
|
|
|
auto dispatch = [&](Action action, RelType rel_type) {
|
|
switch (action) {
|
|
case NONE:
|
|
rel_types[i] = rel_type;
|
|
return;
|
|
case ERROR:
|
|
break;
|
|
case COPYREL:
|
|
sym.flags |= NEEDS_COPYREL;
|
|
rel_types[i] = rel_type;
|
|
return;
|
|
case PLT:
|
|
sym.flags |= NEEDS_PLT;
|
|
rel_types[i] = rel_type;
|
|
return;
|
|
case DYNREL:
|
|
if (is_readonly)
|
|
break;
|
|
sym.flags |= NEEDS_DYNSYM;
|
|
rel_types[i] = R_DYN;
|
|
file.num_dynrel++;
|
|
return;
|
|
case BASEREL:
|
|
if (is_readonly)
|
|
break;
|
|
rel_types[i] = R_BASEREL;
|
|
file.num_dynrel++;
|
|
return;
|
|
default:
|
|
unreachable();
|
|
}
|
|
|
|
Error() << *this << ": " << rel_to_string(rel.r_type)
|
|
<< " relocation against symbol `" << sym
|
|
<< "' can not be used; recompile with -fPIE";
|
|
};
|
|
|
|
if (sym.esym->st_type == STT_GNU_IFUNC)
|
|
sym.flags |= NEEDS_PLT;
|
|
|
|
switch (rel.r_type) {
|
|
case R_X86_64_NONE:
|
|
rel_types[i] = R_NONE;
|
|
break;
|
|
case R_X86_64_8:
|
|
case R_X86_64_16:
|
|
case R_X86_64_32:
|
|
case R_X86_64_32S: {
|
|
// Dynamic linker does not support 8, 16 or 32-bit dynamic
|
|
// relocations for these types of relocations. We report an
|
|
// error if we cannot relocate them even at load-time.
|
|
Action table[][4] = {
|
|
// Absolute Local Imported data Imported code
|
|
{ NONE, NONE, COPYREL, PLT }, // PDE
|
|
{ NONE, ERROR, ERROR, ERROR }, // PIE
|
|
{ NONE, ERROR, ERROR, ERROR }, // DSO
|
|
};
|
|
|
|
dispatch(table[output_type][get_sym_type(sym)], R_ABS);
|
|
break;
|
|
}
|
|
case R_X86_64_64: {
|
|
// Unlike the above, we can use R_X86_64_RELATIVE and R_86_64_64
|
|
// relocations.
|
|
Action table[][4] = {
|
|
// Absolute Local Imported data Imported code
|
|
{ NONE, NONE, COPYREL, PLT }, // PDE
|
|
{ NONE, BASEREL, DYNREL, DYNREL }, // PIE
|
|
{ NONE, BASEREL, DYNREL, DYNREL }, // DSO
|
|
};
|
|
|
|
dispatch(table[output_type][get_sym_type(sym)], R_ABS);
|
|
break;
|
|
}
|
|
case R_X86_64_PC8:
|
|
case R_X86_64_PC16:
|
|
case R_X86_64_PC32: {
|
|
Action table[][4] = {
|
|
// Absolute Local Imported data Imported code
|
|
{ NONE, NONE, COPYREL, PLT }, // PDE
|
|
{ ERROR, NONE, COPYREL, PLT }, // PIE
|
|
{ ERROR, NONE, ERROR, ERROR }, // DSO
|
|
};
|
|
|
|
dispatch(table[output_type][get_sym_type(sym)], R_PC);
|
|
break;
|
|
}
|
|
case R_X86_64_PC64: {
|
|
Action table[][4] = {
|
|
// Absolute Local Imported data Imported code
|
|
{ NONE, NONE, COPYREL, PLT }, // PDE
|
|
{ BASEREL, NONE, COPYREL, PLT }, // PIE
|
|
{ BASEREL, NONE, ERROR, ERROR }, // DSO
|
|
};
|
|
|
|
dispatch(table[output_type][get_sym_type(sym)], R_PC);
|
|
break;
|
|
}
|
|
case R_X86_64_GOT32:
|
|
sym.flags |= NEEDS_GOT;
|
|
rel_types[i] = R_GOT;
|
|
break;
|
|
case R_X86_64_GOTPC32:
|
|
sym.flags |= NEEDS_GOT;
|
|
rel_types[i] = R_GOTPC;
|
|
break;
|
|
case R_X86_64_GOTPCREL:
|
|
sym.flags |= NEEDS_GOT;
|
|
rel_types[i] = R_GOTPCREL;
|
|
break;
|
|
case R_X86_64_GOTPCRELX: {
|
|
if (rel.r_addend != -4)
|
|
Fatal() << *this << ": bad r_addend for R_X86_64_GOTPCRELX";
|
|
|
|
if (config.relax && !sym.is_imported && sym.is_relative()) {
|
|
if (loc[-2] == 0xff && loc[-1] == 0x15) {
|
|
rel_types[i] = R_GOTPCREL_RELAX_CALL;
|
|
break;
|
|
}
|
|
if (loc[-2] == 0xff && loc[-1] == 0x25) {
|
|
rel_types[i] = R_GOTPCREL_RELAX_JMP;
|
|
break;
|
|
}
|
|
}
|
|
|
|
sym.flags |= NEEDS_GOT;
|
|
rel_types[i] = R_GOTPCREL;
|
|
break;
|
|
}
|
|
case R_X86_64_REX_GOTPCRELX:
|
|
if (rel.r_addend != -4)
|
|
Fatal() << *this << ": bad r_addend for R_X86_64_REX_GOTPCRELX";
|
|
|
|
if (config.relax && !sym.is_imported && sym.is_relative() &&
|
|
is_mov_insn(loc - 3)) {
|
|
rel_types[i] = R_GOTPCREL_RELAX_MOV;
|
|
} else {
|
|
sym.flags |= NEEDS_GOT;
|
|
rel_types[i] = R_GOTPCREL;
|
|
}
|
|
break;
|
|
case R_X86_64_PLT32:
|
|
if (sym.is_imported)
|
|
sym.flags |= NEEDS_PLT;
|
|
rel_types[i] = R_PC;
|
|
break;
|
|
case R_X86_64_TLSGD: {
|
|
if (i + 1 == rels.size())
|
|
Fatal() << *this << ": TLSGD reloc must be followed by PLT32 or GOTPCREL";
|
|
|
|
if (config.relax && !config.shared && !sym.is_imported) {
|
|
rel_types[i++] = R_TLSGD_RELAX_LE;
|
|
} else {
|
|
sym.flags |= NEEDS_TLSGD;
|
|
rel_types[i] = R_TLSGD;
|
|
}
|
|
break;
|
|
}
|
|
case R_X86_64_TLSLD:
|
|
if (i + 1 == rels.size())
|
|
Fatal() << *this << ": TLSGD reloc must be followed by PLT32 or GOTPCREL";
|
|
if (sym.is_imported)
|
|
Fatal() << *this << ": TLSLD reloc refers external symbol " << sym;
|
|
|
|
if (config.relax && !config.shared) {
|
|
rel_types[i++] = R_TLSLD_RELAX_LE;
|
|
} else {
|
|
sym.flags |= NEEDS_TLSLD;
|
|
rel_types[i] = R_TLSLD;
|
|
}
|
|
break;
|
|
case R_X86_64_DTPOFF32:
|
|
case R_X86_64_DTPOFF64:
|
|
if (sym.is_imported)
|
|
Fatal() << *this << ": DTPOFF reloc refers external symbol " << sym;
|
|
rel_types[i] = (config.relax && !config.shared) ? R_TPOFF : R_DTPOFF;
|
|
break;
|
|
case R_X86_64_TPOFF32:
|
|
case R_X86_64_TPOFF64:
|
|
rel_types[i] = R_TPOFF;
|
|
break;
|
|
case R_X86_64_GOTTPOFF:
|
|
out::df_static_tls = true;
|
|
|
|
if (config.relax && !config.shared && is_mov_insn(loc - 3)) {
|
|
rel_types[i] = R_GOTTPOFF_RELAX_MOV;
|
|
} else {
|
|
sym.flags |= NEEDS_GOTTPOFF;
|
|
rel_types[i] = R_GOTTPOFF;
|
|
}
|
|
break;
|
|
case R_X86_64_GOTPC32_TLSDESC:
|
|
if (memcmp(loc - 3, "\x48\x8d\x05", 3))
|
|
Fatal() << *this << ": GOTPC32_TLSDESC relocation is used"
|
|
<< " against an invalid code sequence";
|
|
|
|
if (config.relax && !config.shared) {
|
|
rel_types[i] = R_GOTPC_TLSDESC_RELAX_LE;
|
|
} else {
|
|
sym.flags |= NEEDS_TLSDESC;
|
|
rel_types[i] = R_GOTPC_TLSDESC;
|
|
}
|
|
break;
|
|
case R_X86_64_TLSDESC_CALL:
|
|
if (config.relax && !config.shared)
|
|
rel_types[i] = R_TLSDESC_CALL_RELAX;
|
|
else
|
|
rel_types[i] = R_NONE;
|
|
break;
|
|
default:
|
|
Fatal() << *this << ": unknown relocation: " << rel.r_type;
|
|
}
|
|
}
|
|
}
|
|
|
|
void InputSection::kill() {
|
|
if (is_alive.exchange(false)) {
|
|
is_alive = false;
|
|
for (FdeRecord &fde : fdes)
|
|
fde.is_alive = false;
|
|
file.sections[section_idx] = nullptr;
|
|
}
|
|
}
|