/* AArch64-specific support for ELF.
Copyright (C) 2009-2014 Free Software Foundation, Inc.
Contributed by ARM Ltd.
This file is part of BFD, the Binary File Descriptor library.
This program is free software; you can redistribute it and/or modify
it under the terms of the GNU General Public License as published by
the Free Software Foundation; either version 3 of the License, or
(at your option) any later version.
This program is distributed in the hope that it will be useful,
but WITHOUT ANY WARRANTY; without even the implied warranty of
MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
GNU General Public License for more details.
You should have received a copy of the GNU General Public License
along with this program; see the file COPYING3. If not,
see <http://www.gnu.org/licenses/>. */
#include "sysdep.h"
#include "elfxx-aarch64.h"
#include <stdarg.h>
#include <string.h>
#define MASK(n) ((1u << (n)) - 1)
/* Sign-extend VALUE, which has the indicated number of BITS. */
bfd_signed_vma
_bfd_aarch64_sign_extend (bfd_vma value, int bits)
{
if (value & ((bfd_vma) 1 << (bits - 1)))
/* VALUE is negative. */
value |= ((bfd_vma) - 1) << bits;
return value;
}
/* Decode the IMM field of ADRP. */
uint32_t
_bfd_aarch64_decode_adrp_imm (uint32_t insn)
{
return (((insn >> 5) & MASK (19)) << 2) | ((insn >> 29) & MASK (2));
}
/* Reencode the imm field of add immediate. */
static inline uint32_t
reencode_add_imm (uint32_t insn, uint32_t imm)
{
return (insn & ~(MASK (12) << 10)) | ((imm & MASK (12)) << 10);
}
/* Reencode the IMM field of ADR. */
uint32_t
_bfd_aarch64_reencode_adr_imm (uint32_t insn, uint32_t imm)
{
return (insn & ~((MASK (2) << 29) | (MASK (19) << 5)))
| ((imm & MASK (2)) << 29) | ((imm & (MASK (19) << 2)) << 3);
}
/* Reencode the imm field of ld/st pos immediate. */
static inline uint32_t
reencode_ldst_pos_imm (uint32_t insn, uint32_t imm)
{
return (insn & ~(MASK (12) << 10)) | ((imm & MASK (12)) << 10);
}
/* Encode the 26-bit offset of unconditional branch. */
static inline uint32_t
reencode_branch_ofs_26 (uint32_t insn, uint32_t ofs)
{
return (insn & ~MASK (26)) | (ofs & MASK (26));
}
/* Encode the 19-bit offset of conditional branch and compare & branch. */
static inline uint32_t
reencode_cond_branch_ofs_19 (uint32_t insn, uint32_t ofs)
{
return (insn & ~(MASK (19) << 5)) | ((ofs & MASK (19)) << 5);
}
/* Decode the 19-bit offset of load literal. */
static inline uint32_t
reencode_ld_lit_ofs_19 (uint32_t insn, uint32_t ofs)
{
return (insn & ~(MASK (19) << 5)) | ((ofs & MASK (19)) << 5);
}
/* Encode the 14-bit offset of test & branch. */
static inline uint32_t
reencode_tst_branch_ofs_14 (uint32_t insn, uint32_t ofs)
{
return (insn & ~(MASK (14) << 5)) | ((ofs & MASK (14)) << 5);
}
/* Reencode the imm field of move wide. */
static inline uint32_t
reencode_movw_imm (uint32_t insn, uint32_t imm)
{
return (insn & ~(MASK (16) << 5)) | ((imm & MASK (16)) << 5);
}
/* Reencode mov[zn] to movz. */
static inline uint32_t
reencode_movzn_to_movz (uint32_t opcode)
{
return opcode | (1 << 30);
}
/* Reencode mov[zn] to movn. */
static inline uint32_t
reencode_movzn_to_movn (uint32_t opcode)
{
return opcode & ~(1 << 30);
}
/* Return non-zero if the indicated VALUE has overflowed the maximum
range expressible by a unsigned number with the indicated number of
BITS. */
static bfd_reloc_status_type
aarch64_unsigned_overflow (bfd_vma value, unsigned int bits)
{
bfd_vma lim;
if (bits >= sizeof (bfd_vma) * 8)
return bfd_reloc_ok;
lim = (bfd_vma) 1 << bits;
if (value >= lim)
return bfd_reloc_overflow;
return bfd_reloc_ok;
}
/* Return non-zero if the indicated VALUE has overflowed the maximum
range expressible by an signed number with the indicated number of
BITS. */
static bfd_reloc_status_type
aarch64_signed_overflow (bfd_vma value, unsigned int bits)
{
bfd_signed_vma svalue = (bfd_signed_vma) value;
bfd_signed_vma lim;
if (bits >= sizeof (bfd_vma) * 8)
return bfd_reloc_ok;
lim = (bfd_signed_vma) 1 << (bits - 1);
if (svalue < -lim || svalue >= lim)
return bfd_reloc_overflow;
return bfd_reloc_ok;
}
/* Insert the addend/value into the instruction or data object being
relocated. */
bfd_reloc_status_type
_bfd_aarch64_elf_put_addend (bfd *abfd,
bfd_byte *address, bfd_reloc_code_real_type r_type,
reloc_howto_type *howto, bfd_signed_vma addend)
{
bfd_reloc_status_type status = bfd_reloc_ok;
bfd_signed_vma old_addend = addend;
bfd_vma contents;
int size;
size = bfd_get_reloc_size (howto);
switch (size)
{
case 2:
contents = bfd_get_16 (abfd, address);
break;
case 4:
if (howto->src_mask != 0xffffffff)
/* Must be 32-bit instruction, always little-endian. */
contents = bfd_getl32 (address);
else
/* Must be 32-bit data (endianness dependent). */
contents = bfd_get_32 (abfd, address);
break;
case 8:
contents = bfd_get_64 (abfd, address);
break;
default:
abort ();
}
switch (howto->complain_on_overflow)
{
case complain_overflow_dont:
break;
case complain_overflow_signed:
status = aarch64_signed_overflow (addend,
howto->bitsize + howto->rightshift);
break;
case complain_overflow_unsigned:
status = aarch64_unsigned_overflow (addend,
howto->bitsize + howto->rightshift);
break;
case complain_overflow_bitfield:
default:
abort ();
}
addend >>= howto->rightshift;
switch (r_type)
{
case BFD_RELOC_AARCH64_JUMP26:
case BFD_RELOC_AARCH64_CALL26:
contents = reencode_branch_ofs_26 (contents, addend);
break;
case BFD_RELOC_AARCH64_BRANCH19:
contents = reencode_cond_branch_ofs_19 (contents, addend);
break;
case BFD_RELOC_AARCH64_TSTBR14:
contents = reencode_tst_branch_ofs_14 (contents, addend);
break;
case BFD_RELOC_AARCH64_LD_LO19_PCREL:
case BFD_RELOC_AARCH64_GOT_LD_PREL19:
if (old_addend & ((1 << howto->rightshift) - 1))
return bfd_reloc_overflow;
contents = reencode_ld_lit_ofs_19 (contents, addend);
break;
case BFD_RELOC_AARCH64_TLSDESC_CALL:
break;
case BFD_RELOC_AARCH64_TLSGD_ADR_PAGE21:
case BFD_RELOC_AARCH64_TLSIE_ADR_GOTTPREL_PAGE21:
case BFD_RELOC_AARCH64_TLSDESC_ADR_PAGE21:
case BFD_RELOC_AARCH64_ADR_GOT_PAGE:
case BFD_RELOC_AARCH64_ADR_LO21_PCREL:
case BFD_RELOC_AARCH64_ADR_HI21_PCREL:
case BFD_RELOC_AARCH64_ADR_HI21_NC_PCREL:
contents = _bfd_aarch64_reencode_adr_imm (contents, addend);
break;
case BFD_RELOC_AARCH64_TLSGD_ADD_LO12_NC:
case BFD_RELOC_AARCH64_TLSLE_ADD_TPREL_LO12:
case BFD_RELOC_AARCH64_TLSLE_ADD_TPREL_HI12:
case BFD_RELOC_AARCH64_TLSLE_ADD_TPREL_LO12_NC:
case BFD_RELOC_AARCH64_TLSDESC_ADD_LO12_NC:
case BFD_RELOC_AARCH64_ADD_LO12:
/* Corresponds to: add rd, rn, #uimm12 to provide the low order
12 bits of the page offset following
BFD_RELOC_AARCH64_ADR_HI21_PCREL which computes the
(pc-relative) page base. */
contents = reencode_add_imm (contents, addend);
break;
case BFD_RELOC_AARCH64_LDST8_LO12:
case BFD_RELOC_AARCH64_LDST16_LO12:
case BFD_RELOC_AARCH64_LDST32_LO12:
case BFD_RELOC_AARCH64_LDST64_LO12:
case BFD_RELOC_AARCH64_LDST128_LO12:
case BFD_RELOC_AARCH64_TLSDESC_LD64_LO12_NC:
case BFD_RELOC_AARCH64_TLSDESC_LD32_LO12_NC:
case BFD_RELOC_AARCH64_TLSIE_LD64_GOTTPREL_LO12_NC:
case BFD_RELOC_AARCH64_TLSIE_LD32_GOTTPREL_LO12_NC:
case BFD_RELOC_AARCH64_LD64_GOT_LO12_NC:
case BFD_RELOC_AARCH64_LD32_GOT_LO12_NC:
if (old_addend & ((1 << howto->rightshift) - 1))
return bfd_reloc_overflow;
/* Used for ldr*|str* rt, [rn, #uimm12] to provide the low order
12 bits of the page offset following BFD_RELOC_AARCH64_ADR_HI21_PCREL
which computes the (pc-relative) page base. */
contents = reencode_ldst_pos_imm (contents, addend);
break;
/* Group relocations to create high bits of a 16, 32, 48 or 64
bit signed data or abs address inline. Will change
instruction to MOVN or MOVZ depending on sign of calculated
value. */
case BFD_RELOC_AARCH64_TLSLE_MOVW_TPREL_G2:
case BFD_RELOC_AARCH64_TLSLE_MOVW_TPREL_G1:
case BFD_RELOC_AARCH64_TLSLE_MOVW_TPREL_G1_NC:
case BFD_RELOC_AARCH64_TLSLE_MOVW_TPREL_G0:
case BFD_RELOC_AARCH64_TLSLE_MOVW_TPREL_G0_NC:
case BFD_RELOC_AARCH64_MOVW_G0_S:
case BFD_RELOC_AARCH64_MOVW_G1_S:
case BFD_RELOC_AARCH64_MOVW_G2_S:
/* NOTE: We can only come here with movz or movn. */
if (addend < 0)
{
/* Force use of MOVN. */
addend = ~addend;
contents = reencode_movzn_to_movn (contents);
}
else
{
/* Force use of MOVZ. */
contents = reencode_movzn_to_movz (contents);
}
/* fall through */
/* Group relocations to create a 16, 32, 48 or 64 bit unsigned
data or abs address inline. */
case BFD_RELOC_AARCH64_MOVW_G0:
case BFD_RELOC_AARCH64_MOVW_G0_NC:
case BFD_RELOC_AARCH64_MOVW_G1:
case BFD_RELOC_AARCH64_MOVW_G1_NC:
case BFD_RELOC_AARCH64_MOVW_G2:
case BFD_RELOC_AARCH64_MOVW_G2_NC:
case BFD_RELOC_AARCH64_MOVW_G3:
contents = reencode_movw_imm (contents, addend);
break;
default:
/* Repack simple data */
if (howto->dst_mask & (howto->dst_mask + 1))
return bfd_reloc_notsupported;
contents = ((contents & ~howto->dst_mask) | (addend & howto->dst_mask));
break;
}
switch (size)
{
case 2:
bfd_put_16 (abfd, contents, address);
break;
case 4:
if (howto->dst_mask != 0xffffffff)
/* must be 32-bit instruction, always little-endian */
bfd_putl32 (contents, address);
else
/* must be 32-bit data (endianness dependent) */
bfd_put_32 (abfd, contents, address);
break;
case 8:
bfd_put_64 (abfd, contents, address);
break;
default:
abort ();
}
return status;
}
bfd_vma
_bfd_aarch64_elf_resolve_relocation (bfd_reloc_code_real_type r_type,
bfd_vma place, bfd_vma value,
bfd_vma addend, bfd_boolean weak_undef_p)
{
switch (r_type)
{
case BFD_RELOC_AARCH64_TLSDESC_CALL:
case BFD_RELOC_AARCH64_NONE:
break;
case BFD_RELOC_AARCH64_ADR_LO21_PCREL:
case BFD_RELOC_AARCH64_BRANCH19:
case BFD_RELOC_AARCH64_LD_LO19_PCREL:
case BFD_RELOC_AARCH64_16_PCREL:
case BFD_RELOC_AARCH64_32_PCREL:
case BFD_RELOC_AARCH64_64_PCREL:
case BFD_RELOC_AARCH64_TSTBR14:
if (weak_undef_p)
value = place;
value = value + addend - place;
break;
case BFD_RELOC_AARCH64_CALL26:
case BFD_RELOC_AARCH64_JUMP26:
value = value + addend - place;
break;
case BFD_RELOC_AARCH64_16:
case BFD_RELOC_AARCH64_32:
case BFD_RELOC_AARCH64_MOVW_G0_S:
case BFD_RELOC_AARCH64_MOVW_G1_S:
case BFD_RELOC_AARCH64_MOVW_G2_S:
case BFD_RELOC_AARCH64_MOVW_G0:
case BFD_RELOC_AARCH64_MOVW_G0_NC:
case BFD_RELOC_AARCH64_MOVW_G1:
case BFD_RELOC_AARCH64_MOVW_G1_NC:
case BFD_RELOC_AARCH64_MOVW_G2:
case BFD_RELOC_AARCH64_MOVW_G2_NC:
case BFD_RELOC_AARCH64_MOVW_G3:
value = value + addend;
break;
case BFD_RELOC_AARCH64_ADR_HI21_PCREL:
case BFD_RELOC_AARCH64_ADR_HI21_NC_PCREL:
if (weak_undef_p)
value = PG (place);
value = PG (value + addend) - PG (place);
break;
case BFD_RELOC_AARCH64_GOT_LD_PREL19:
value = value + addend - place;
break;
case BFD_RELOC_AARCH64_ADR_GOT_PAGE:
case BFD_RELOC_AARCH64_TLSDESC_ADR_PAGE21:
case BFD_RELOC_AARCH64_TLSGD_ADR_PAGE21:
case BFD_RELOC_AARCH64_TLSIE_ADR_GOTTPREL_PAGE21:
value = PG (value + addend) - PG (place);
break;
case BFD_RELOC_AARCH64_ADD_LO12:
case BFD_RELOC_AARCH64_LD64_GOT_LO12_NC:
case BFD_RELOC_AARCH64_LD32_GOT_LO12_NC:
case BFD_RELOC_AARCH64_LDST8_LO12:
case BFD_RELOC_AARCH64_LDST16_LO12:
case BFD_RELOC_AARCH64_LDST32_LO12:
case BFD_RELOC_AARCH64_LDST64_LO12:
case BFD_RELOC_AARCH64_LDST128_LO12:
case BFD_RELOC_AARCH64_TLSDESC_ADD_LO12_NC:
case BFD_RELOC_AARCH64_TLSDESC_ADD:
case BFD_RELOC_AARCH64_TLSDESC_LD64_LO12_NC:
case BFD_RELOC_AARCH64_TLSDESC_LD32_LO12_NC:
case BFD_RELOC_AARCH64_TLSDESC_LDR:
case BFD_RELOC_AARCH64_TLSGD_ADD_LO12_NC:
case BFD_RELOC_AARCH64_TLSIE_LD64_GOTTPREL_LO12_NC:
case BFD_RELOC_AARCH64_TLSIE_LD32_GOTTPREL_LO12_NC:
case BFD_RELOC_AARCH64_TLSLE_ADD_TPREL_LO12:
case BFD_RELOC_AARCH64_TLSLE_ADD_TPREL_LO12_NC:
value = PG_OFFSET (value + addend);
break;
case BFD_RELOC_AARCH64_TLSLE_MOVW_TPREL_G1:
case BFD_RELOC_AARCH64_TLSLE_MOVW_TPREL_G1_NC:
value = (value + addend) & (bfd_vma) 0xffff0000;
break;
case BFD_RELOC_AARCH64_TLSLE_ADD_TPREL_HI12:
value = (value + addend) & (bfd_vma) 0xfff000;
break;
case BFD_RELOC_AARCH64_TLSLE_MOVW_TPREL_G0:
case BFD_RELOC_AARCH64_TLSLE_MOVW_TPREL_G0_NC:
value = (value + addend) & (bfd_vma) 0xffff;
break;
case BFD_RELOC_AARCH64_TLSLE_MOVW_TPREL_G2:
value = (value + addend) & ~(bfd_vma) 0xffffffff;
value -= place & ~(bfd_vma) 0xffffffff;
break;
default:
break;
}
return value;
}
/* Hook called by the linker routine which adds symbols from an object
file. */
bfd_boolean
_bfd_aarch64_elf_add_symbol_hook (bfd *abfd, struct bfd_link_info *info,
Elf_Internal_Sym *sym,
const char **namep ATTRIBUTE_UNUSED,
flagword *flagsp ATTRIBUTE_UNUSED,
asection **secp ATTRIBUTE_UNUSED,
bfd_vma *valp ATTRIBUTE_UNUSED)
{
if ((ELF_ST_TYPE (sym->st_info) == STT_GNU_IFUNC
|| ELF_ST_BIND (sym->st_info) == STB_GNU_UNIQUE)
&& (abfd->flags & DYNAMIC) == 0
&& bfd_get_flavour (info->output_bfd) == bfd_target_elf_flavour)
elf_tdata (info->output_bfd)->has_gnu_symbols = TRUE;
return TRUE;
}
/* Support for core dump NOTE sections. */
bfd_boolean
_bfd_aarch64_elf_grok_prstatus (bfd *abfd, Elf_Internal_Note *note)
{
int offset;
size_t size;
switch (note->descsz)
{
default:
return FALSE;
case 392: /* sizeof(struct elf_prstatus) on Linux/arm64. */
/* pr_cursig */
elf_tdata (abfd)->core->signal
= bfd_get_16 (abfd, note->descdata + 12);
/* pr_pid */
elf_tdata (abfd)->core->lwpid
= bfd_get_32 (abfd, note->descdata + 32);
/* pr_reg */
offset = 112;
size = 272;
break;
}
/* Make a ".reg/999" section. */
return _bfd_elfcore_make_pseudosection (abfd, ".reg",
size, note->descpos + offset);
}
bfd_boolean
_bfd_aarch64_elf_grok_psinfo (bfd *abfd, Elf_Internal_Note *note)
{
switch (note->descsz)
{
default:
return FALSE;
case 136: /* This is sizeof(struct elf_prpsinfo) on Linux/aarch64. */
elf_tdata (abfd)->core->pid = bfd_get_32 (abfd, note->descdata + 24);
elf_tdata (abfd)->core->program
= _bfd_elfcore_strndup (abfd, note->descdata + 40, 16);
elf_tdata (abfd)->core->command
= _bfd_elfcore_strndup (abfd, note->descdata + 56, 80);
}
/* Note that for some reason, a spurious space is tacked
onto the end of the args in some (at least one anyway)
implementations, so strip it off if it exists. */
{
char *command = elf_tdata (abfd)->core->command;
int n = strlen (command);
if (0 < n && command[n - 1] == ' ')
command[n - 1] = '\0';
}
return TRUE;
}
char *
_bfd_aarch64_elf_write_core_note (bfd *abfd, char *buf, int *bufsiz, int note_type,
...)
{
switch (note_type)
{
default:
return NULL;
case NT_PRPSINFO:
{
char data[136];
va_list ap;
va_start (ap, note_type);
memset (data, 0, sizeof (data));
strncpy (data + 40, va_arg (ap, const char *), 16);
strncpy (data + 56, va_arg (ap, const char *), 80);
va_end (ap);
return elfcore_write_note (abfd, buf, bufsiz, "CORE",
note_type, data, sizeof (data));
}
case NT_PRSTATUS:
{
char data[392];
va_list ap;
long pid;
int cursig;
const void *greg;
va_start (ap, note_type);
memset (data, 0, sizeof (data));
pid = va_arg (ap, long);
bfd_put_32 (abfd, pid, data + 32);
cursig = va_arg (ap, int);
bfd_put_16 (abfd, cursig, data + 12);
greg = va_arg (ap, const void *);
memcpy (data + 112, greg, 272);
va_end (ap);
return elfcore_write_note (abfd, buf, bufsiz, "CORE",
note_type, data, sizeof (data));
}
}
}