static tls::Tls_optimization
optimize_tls_reloc(bool is_final, int r_type);
+ // Check if relocation against this symbol is a candidate for
+ // conversion from
+ // mov foo@GOT(%reg), %reg
+ // to
+ // lea foo@GOTOFF(%reg), %reg.
+ static bool
+ can_convert_mov_to_lea(const Symbol* gsym)
+ {
+ gold_assert(gsym != NULL);
+ return (gsym->type() != elfcpp::STT_GNU_IFUNC
+ && !gsym->is_undefined ()
+ && !gsym->is_from_dynobj()
+ && !gsym->is_preemptible()
+ && (!parameters->options().shared()
+ || (gsym->visibility() != elfcpp::STV_DEFAULT
+ && gsym->visibility() != elfcpp::STV_PROTECTED)
+ || parameters->options().Bsymbolic())
+ && strcmp(gsym->name(), "_DYNAMIC") != 0);
+ }
+
// Get the GOT section, creating it if necessary.
Output_data_got<32, false>*
got_section(Symbol_table*, Layout*);
0, // large_common_section_flags
NULL, // attributes_section
NULL, // attributes_vendor
- "_start" // entry_symbol_name
+ "_start", // entry_symbol_name
+ 32, // hash_entry_size
};
// Get the GOT section, creating it if necessary.
return Symbol::FUNCTION_CALL | Symbol::RELATIVE_REF;
case elfcpp::R_386_GOT32:
+ case elfcpp::R_386_GOT32X:
// Absolute in GOT.
return Symbol::ABSOLUTE_REF;
break;
case elfcpp::R_386_GOT32:
+ case elfcpp::R_386_GOT32X:
{
- // The symbol requires a GOT entry.
+ // We need GOT section.
Output_data_got<32, false>* got = target->got_section(symtab, layout);
+
+ // If the relocation symbol isn't IFUNC,
+ // and is local, then we will convert
+ // mov foo@GOT(%reg), %reg
+ // to
+ // lea foo@GOTOFF(%reg), %reg
+ // in Relocate::relocate.
+ if (reloc.get_r_offset() >= 2
+ && lsym.get_st_type() != elfcpp::STT_GNU_IFUNC)
+ {
+ section_size_type stype;
+ const unsigned char* view = object->section_contents(data_shndx,
+ &stype, true);
+ if (view[reloc.get_r_offset() - 2] == 0x8b)
+ break;
+ }
+
+ // Otherwise, the symbol requires a GOT entry.
unsigned int r_sym = elfcpp::elf_r_sym<32>(reloc.get_r_info());
// For a STT_GNU_IFUNC symbol we want the PLT offset. That
case elfcpp::R_386_8:
case elfcpp::R_386_GOTOFF:
case elfcpp::R_386_GOT32:
+ case elfcpp::R_386_GOT32X:
{
return true;
}
break;
case elfcpp::R_386_GOT32:
+ case elfcpp::R_386_GOT32X:
{
- // The symbol requires a GOT entry.
+ // The symbol requires a GOT section.
Output_data_got<32, false>* got = target->got_section(symtab, layout);
+
+ // If we convert this from
+ // mov foo@GOT(%reg), %reg
+ // to
+ // lea foo@GOTOFF(%reg), %reg
+ // in Relocate::relocate, then there is nothing to do here.
+ if (reloc.get_r_offset() >= 2
+ && Target_i386::can_convert_mov_to_lea(gsym))
+ {
+ section_size_type stype;
+ const unsigned char* view = object->section_contents(data_shndx,
+ &stype, true);
+ if (view[reloc.get_r_offset() - 2] == 0x8b)
+ break;
+ }
+
if (gsym->final_value_is_known())
{
// For a STT_GNU_IFUNC symbol we want the PLT address.
}
}
- // Get the GOT offset if needed.
- // The GOT pointer points to the end of the GOT section.
- // We need to subtract the size of the GOT section to get
- // the actual offset to use in the relocation.
- bool have_got_offset = false;
- unsigned int got_offset = 0;
- switch (r_type)
- {
- case elfcpp::R_386_GOT32:
- if (gsym != NULL)
- {
- gold_assert(gsym->has_got_offset(GOT_TYPE_STANDARD));
- got_offset = (gsym->got_offset(GOT_TYPE_STANDARD)
- - target->got_size());
- }
- else
- {
- unsigned int r_sym = elfcpp::elf_r_sym<32>(rel.get_r_info());
- gold_assert(object->local_has_got_offset(r_sym, GOT_TYPE_STANDARD));
- got_offset = (object->local_got_offset(r_sym, GOT_TYPE_STANDARD)
- - target->got_size());
- }
- have_got_offset = true;
- break;
-
- default:
- break;
- }
+ bool baseless;
switch (r_type)
{
break;
case elfcpp::R_386_GOT32:
- gold_assert(have_got_offset);
- Relocate_functions<32, false>::rel32(view, got_offset);
+ case elfcpp::R_386_GOT32X:
+ baseless = (view[-1] & 0xc7) == 0x5;
+ // R_386_GOT32 and R_386_GOT32X don't work without base register
+ // when generating a position-independent output file.
+ if (baseless
+ && parameters->options().output_is_position_independent())
+ {
+ if(gsym)
+ gold_error_at_location(relinfo, relnum, rel.get_r_offset(),
+ _("unexpected reloc %u against global symbol %s without base register in object file when generating a position-independent output file"),
+ r_type, gsym->demangled_name().c_str());
+ else
+ gold_error_at_location(relinfo, relnum, rel.get_r_offset(),
+ _("unexpected reloc %u against local symbol without base register in object file when generating a position-independent output file"),
+ r_type);
+ }
+
+ // Convert
+ // mov foo@GOT(%reg), %reg
+ // to
+ // lea foo@GOTOFF(%reg), %reg
+ // if possible.
+ if (rel.get_r_offset() >= 2
+ && view[-2] == 0x8b
+ && ((gsym == NULL && !psymval->is_ifunc_symbol())
+ || (gsym != NULL
+ && Target_i386::can_convert_mov_to_lea(gsym))))
+ {
+ view[-2] = 0x8d;
+ elfcpp::Elf_types<32>::Elf_Addr value;
+ value = psymval->value(object, 0);
+ // Don't subtract the .got.plt section address for baseless
+ // addressing.
+ if (!baseless)
+ value -= target->got_plt_section()->address();
+ Relocate_functions<32, false>::rel32(view, value);
+ }
+ else
+ {
+ // The GOT pointer points to the end of the GOT section.
+ // We need to subtract the size of the GOT section to get
+ // the actual offset to use in the relocation.
+ unsigned int got_offset = 0;
+ if (gsym != NULL)
+ {
+ gold_assert(gsym->has_got_offset(GOT_TYPE_STANDARD));
+ got_offset = (gsym->got_offset(GOT_TYPE_STANDARD)
+ - target->got_size());
+ }
+ else
+ {
+ unsigned int r_sym = elfcpp::elf_r_sym<32>(rel.get_r_info());
+ gold_assert(object->local_has_got_offset(r_sym, GOT_TYPE_STANDARD));
+ got_offset = (object->local_got_offset(r_sym, GOT_TYPE_STANDARD)
+ - target->got_size());
+ }
+ // Add the .got.plt section address for baseless addressing.
+ if (baseless)
+ got_offset += target->got_plt_section()->address();
+ Relocate_functions<32, false>::rel32(view, got_offset);
+ }
break;
case elfcpp::R_386_GOTOFF:
{
// leal foo(,%ebx,1),%eax; call ___tls_get_addr
// ==> movl %gs:0,%eax; addl foo@gotntpoff(%ebx),%eax
+ // leal foo(%ebx),%eax; call ___tls_get_addr; nop
+ // ==> movl %gs:0,%eax; addl foo@gotntpoff(%ebx),%eax
tls::check_range(relinfo, relnum, rel.get_r_offset(), view_size, -2);
tls::check_range(relinfo, relnum, rel.get_r_offset(), view_size, 9);
op2 == 0x8d || op2 == 0x04);
tls::check_tls(relinfo, relnum, rel.get_r_offset(), view[4] == 0xe8);
- int roff = 5;
-
- // FIXME: For now, support only the first (SIB) form.
- tls::check_tls(relinfo, relnum, rel.get_r_offset(), op2 == 0x04);
+ int roff;
if (op2 == 0x04)
{
tls::check_tls(relinfo, relnum, rel.get_r_offset(), view[-3] == 0x8d);
tls::check_tls(relinfo, relnum, rel.get_r_offset(),
((op1 & 0xc7) == 0x05 && op1 != (4 << 3)));
- memcpy(view - 3, "\x65\xa1\0\0\0\0\x03\x83\0\0\0", 12);
+ roff = 5;
}
else
{
+ tls::check_range(relinfo, relnum, rel.get_r_offset(), view_size, 10);
tls::check_tls(relinfo, relnum, rel.get_r_offset(),
(op1 & 0xf8) == 0x80 && (op1 & 7) != 4);
- if (rel.get_r_offset() + 9 < view_size
- && view[9] == 0x90)
- {
- // FIXME: This is not the right instruction sequence.
- // There is a trailing nop. Use the size byte subl.
- memcpy(view - 2, "\x65\xa1\0\0\0\0\x81\xe8\0\0\0", 12);
- roff = 6;
- }
- else
- {
- // FIXME: This is not the right instruction sequence.
- // Use the five byte subl.
- memcpy(view - 2, "\x65\xa1\0\0\0\0\x2d\0\0\0", 11);
- }
+ tls::check_tls(relinfo, relnum, rel.get_r_offset(), view[9] == 0x90);
+ roff = 6;
}
+ memcpy(view + roff - 8, "\x65\xa1\0\0\0\0\x03\x83\0\0\0", 12);
Relocate_functions<32, false>::rel32(view + roff, value);
// The next reloc should be a PLT32 reloc against __tls_get_addr.
case elfcpp::R_386_32:
case elfcpp::R_386_PC32:
case elfcpp::R_386_GOT32:
+ case elfcpp::R_386_GOT32X:
case elfcpp::R_386_PLT32:
case elfcpp::R_386_GOTOFF:
case elfcpp::R_386_GOTPC:
0, // large_common_section_flags
NULL, // attributes_section
NULL, // attributes_vendor
- "_start" // entry_symbol_name
+ "_start", // entry_symbol_name
+ 32, // hash_entry_size
};
#define NACLMASK 0xe0 // 32-byte alignment mask
Target_selector_i386_nacl target_selector_i386;
+// IAMCU variant. It uses EM_IAMCU, not EM_386.
+
+class Target_iamcu : public Target_i386
+{
+ public:
+ Target_iamcu()
+ : Target_i386(&iamcu_info)
+ { }
+
+ private:
+ // Information about this specific target which we pass to the
+ // general Target structure.
+ static const Target::Target_info iamcu_info;
+};
+
+const Target::Target_info Target_iamcu::iamcu_info =
+{
+ 32, // size
+ false, // is_big_endian
+ elfcpp::EM_IAMCU, // machine_code
+ false, // has_make_symbol
+ false, // has_resolve
+ true, // has_code_fill
+ true, // is_default_stack_executable
+ true, // can_icf_inline_merge_sections
+ '\0', // wrap_char
+ "/usr/lib/libc.so.1", // dynamic_linker
+ 0x08048000, // default_text_segment_address
+ 0x1000, // abi_pagesize (overridable by -z max-page-size)
+ 0x1000, // common_pagesize (overridable by -z common-page-size)
+ false, // isolate_execinstr
+ 0, // rosegment_gap
+ elfcpp::SHN_UNDEF, // small_common_shndx
+ elfcpp::SHN_UNDEF, // large_common_shndx
+ 0, // small_common_section_flags
+ 0, // large_common_section_flags
+ NULL, // attributes_section
+ NULL, // attributes_vendor
+ "_start", // entry_symbol_name
+ 32, // hash_entry_size
+};
+
+class Target_selector_iamcu : public Target_selector
+{
+public:
+ Target_selector_iamcu()
+ : Target_selector(elfcpp::EM_IAMCU, 32, false, "elf32-iamcu",
+ "elf_iamcu")
+ { }
+
+ Target*
+ do_instantiate_target()
+ { return new Target_iamcu(); }
+};
+
+Target_selector_iamcu target_selector_iamcu;
+
} // End anonymous namespace.