path: root/bfd/elfxx-aarch64.c

/* AArch64-specific support for ELF.
   Copyright (C) 2009-2018 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 0:
      return status;
    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_CALL26:
    case BFD_RELOC_AARCH64_JUMP26:
      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_GOT_LD_PREL19:
    case BFD_RELOC_AARCH64_LD_LO19_PCREL:
    case BFD_RELOC_AARCH64_TLSDESC_LD_PREL19:
    case BFD_RELOC_AARCH64_TLSIE_LD_GOTTPREL_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_ADR_GOT_PAGE:
    case BFD_RELOC_AARCH64_ADR_HI21_NC_PCREL:
    case BFD_RELOC_AARCH64_ADR_HI21_PCREL:
    case BFD_RELOC_AARCH64_ADR_LO21_PCREL:
    case BFD_RELOC_AARCH64_TLSDESC_ADR_PAGE21:
    case BFD_RELOC_AARCH64_TLSDESC_ADR_PREL21:
    case BFD_RELOC_AARCH64_TLSGD_ADR_PAGE21:
    case BFD_RELOC_AARCH64_TLSGD_ADR_PREL21:
    case BFD_RELOC_AARCH64_TLSIE_ADR_GOTTPREL_PAGE21:
    case BFD_RELOC_AARCH64_TLSLD_ADR_PAGE21:
    case BFD_RELOC_AARCH64_TLSLD_ADR_PREL21:
      contents = _bfd_aarch64_reencode_adr_imm (contents, addend);
      break;

    case BFD_RELOC_AARCH64_ADD_LO12:
    case BFD_RELOC_AARCH64_TLSDESC_ADD_LO12:
    case BFD_RELOC_AARCH64_TLSGD_ADD_LO12_NC:
    case BFD_RELOC_AARCH64_TLSLD_ADD_DTPREL_HI12:
    case BFD_RELOC_AARCH64_TLSLD_ADD_DTPREL_LO12:
    case BFD_RELOC_AARCH64_TLSLD_ADD_DTPREL_LO12_NC:
    case BFD_RELOC_AARCH64_TLSLD_ADD_LO12_NC:
    case BFD_RELOC_AARCH64_TLSLE_ADD_TPREL_HI12:
    case BFD_RELOC_AARCH64_TLSLE_ADD_TPREL_LO12:
    case BFD_RELOC_AARCH64_TLSLE_ADD_TPREL_LO12_NC:
      /* 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_LD32_GOTPAGE_LO14:
    case BFD_RELOC_AARCH64_LD32_GOT_LO12_NC:
    case BFD_RELOC_AARCH64_LD64_GOTOFF_LO15:
    case BFD_RELOC_AARCH64_LD64_GOTPAGE_LO15:
    case BFD_RELOC_AARCH64_LD64_GOT_LO12_NC:
    case BFD_RELOC_AARCH64_LDST128_LO12:
    case BFD_RELOC_AARCH64_LDST16_LO12:
    case BFD_RELOC_AARCH64_LDST32_LO12:
    case BFD_RELOC_AARCH64_LDST64_LO12:
    case BFD_RELOC_AARCH64_LDST8_LO12:
    case BFD_RELOC_AARCH64_TLSDESC_LD32_LO12_NC:
    case BFD_RELOC_AARCH64_TLSDESC_LD64_LO12:
    case BFD_RELOC_AARCH64_TLSIE_LD32_GOTTPREL_LO12_NC:
    case BFD_RELOC_AARCH64_TLSIE_LD64_GOTTPREL_LO12_NC:
    case BFD_RELOC_AARCH64_TLSLD_LDST16_DTPREL_LO12:
    case BFD_RELOC_AARCH64_TLSLD_LDST16_DTPREL_LO12_NC:
    case BFD_RELOC_AARCH64_TLSLD_LDST32_DTPREL_LO12:
    case BFD_RELOC_AARCH64_TLSLD_LDST32_DTPREL_LO12_NC:
    case BFD_RELOC_AARCH64_TLSLD_LDST64_DTPREL_LO12:
    case BFD_RELOC_AARCH64_TLSLD_LDST64_DTPREL_LO12_NC:
    case BFD_RELOC_AARCH64_TLSLD_LDST8_DTPREL_LO12:
    case BFD_RELOC_AARCH64_TLSLD_LDST8_DTPREL_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_MOVW_G0_S:
    case BFD_RELOC_AARCH64_MOVW_G1_S:
    case BFD_RELOC_AARCH64_MOVW_G2_S:
    case BFD_RELOC_AARCH64_TLSLD_MOVW_DTPREL_G0:
    case BFD_RELOC_AARCH64_TLSLD_MOVW_DTPREL_G1:
    case BFD_RELOC_AARCH64_TLSLD_MOVW_DTPREL_G2:
    case BFD_RELOC_AARCH64_TLSLE_MOVW_TPREL_G0:
    case BFD_RELOC_AARCH64_TLSLE_MOVW_TPREL_G1:
    case BFD_RELOC_AARCH64_TLSLE_MOVW_TPREL_G2:
      /* 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:
    case BFD_RELOC_AARCH64_MOVW_GOTOFF_G0_NC:
    case BFD_RELOC_AARCH64_MOVW_GOTOFF_G1:
    case BFD_RELOC_AARCH64_TLSDESC_OFF_G0_NC:
    case BFD_RELOC_AARCH64_TLSDESC_OFF_G1:
    case BFD_RELOC_AARCH64_TLSGD_MOVW_G0_NC:
    case BFD_RELOC_AARCH64_TLSGD_MOVW_G1:
    case BFD_RELOC_AARCH64_TLSIE_MOVW_GOTTPREL_G0_NC:
    case BFD_RELOC_AARCH64_TLSIE_MOVW_GOTTPREL_G1:
    case BFD_RELOC_AARCH64_TLSLD_MOVW_DTPREL_G0_NC:
    case BFD_RELOC_AARCH64_TLSLD_MOVW_DTPREL_G1_NC:
    case BFD_RELOC_AARCH64_TLSLE_MOVW_TPREL_G0_NC:
    case BFD_RELOC_AARCH64_TLSLE_MOVW_TPREL_G1_NC:
      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_NONE:
    case BFD_RELOC_AARCH64_TLSDESC_CALL:
      break;

    case BFD_RELOC_AARCH64_16_PCREL:
    case BFD_RELOC_AARCH64_32_PCREL:
    case BFD_RELOC_AARCH64_64_PCREL:
    case BFD_RELOC_AARCH64_ADR_LO21_PCREL:
    case BFD_RELOC_AARCH64_BRANCH19:
    case BFD_RELOC_AARCH64_LD_LO19_PCREL:
    case BFD_RELOC_AARCH64_TLSDESC_ADR_PREL21:
    case BFD_RELOC_AARCH64_TLSDESC_LD_PREL19:
    case BFD_RELOC_AARCH64_TLSGD_ADR_PREL21:
    case BFD_RELOC_AARCH64_TLSIE_LD_GOTTPREL_PREL19:
    case BFD_RELOC_AARCH64_TLSLD_ADR_PREL21:
    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:
    case BFD_RELOC_AARCH64_MOVW_G0_NC:
    case BFD_RELOC_AARCH64_MOVW_G0_S:
    case BFD_RELOC_AARCH64_MOVW_G1:
    case BFD_RELOC_AARCH64_MOVW_G1_NC:
    case BFD_RELOC_AARCH64_MOVW_G1_S:
    case BFD_RELOC_AARCH64_MOVW_G2:
    case BFD_RELOC_AARCH64_MOVW_G2_NC:
    case BFD_RELOC_AARCH64_MOVW_G2_S:
    case BFD_RELOC_AARCH64_MOVW_G3:
    case BFD_RELOC_AARCH64_TLSDESC_OFF_G0_NC:
    case BFD_RELOC_AARCH64_TLSDESC_OFF_G1:
    case BFD_RELOC_AARCH64_TLSGD_MOVW_G0_NC:
    case BFD_RELOC_AARCH64_TLSGD_MOVW_G1:
    case BFD_RELOC_AARCH64_TLSLD_ADD_DTPREL_HI12:
    case BFD_RELOC_AARCH64_TLSLD_ADD_DTPREL_LO12:
    case BFD_RELOC_AARCH64_TLSLD_ADD_DTPREL_LO12_NC:
    case BFD_RELOC_AARCH64_TLSLD_LDST16_DTPREL_LO12:
    case BFD_RELOC_AARCH64_TLSLD_LDST16_DTPREL_LO12_NC:
    case BFD_RELOC_AARCH64_TLSLD_LDST32_DTPREL_LO12:
    case BFD_RELOC_AARCH64_TLSLD_LDST32_DTPREL_LO12_NC:
    case BFD_RELOC_AARCH64_TLSLD_LDST64_DTPREL_LO12:
    case BFD_RELOC_AARCH64_TLSLD_LDST64_DTPREL_LO12_NC:
    case BFD_RELOC_AARCH64_TLSLD_LDST8_DTPREL_LO12:
    case BFD_RELOC_AARCH64_TLSLD_LDST8_DTPREL_LO12_NC:
    case BFD_RELOC_AARCH64_TLSLD_MOVW_DTPREL_G0:
    case BFD_RELOC_AARCH64_TLSLD_MOVW_DTPREL_G0_NC:
    case BFD_RELOC_AARCH64_TLSLD_MOVW_DTPREL_G1:
    case BFD_RELOC_AARCH64_TLSLD_MOVW_DTPREL_G1_NC:
    case BFD_RELOC_AARCH64_TLSLD_MOVW_DTPREL_G2:
      value = value + addend;
      break;

    case BFD_RELOC_AARCH64_ADR_HI21_NC_PCREL:
    case BFD_RELOC_AARCH64_ADR_HI21_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:
    case BFD_RELOC_AARCH64_TLSLD_ADR_PAGE21:
      value = PG (value + addend) - PG (place);
      break;

    /* Caller must make sure addend is the base address of .got section.  */
    case BFD_RELOC_AARCH64_LD32_GOTPAGE_LO14:
    case BFD_RELOC_AARCH64_LD64_GOTPAGE_LO15:
      addend = PG (addend);
      /* Fall through.  */
    case BFD_RELOC_AARCH64_LD64_GOTOFF_LO15:
    case BFD_RELOC_AARCH64_MOVW_GOTOFF_G0_NC:
    case BFD_RELOC_AARCH64_MOVW_GOTOFF_G1:
      value = value - addend;
      break;

    case BFD_RELOC_AARCH64_ADD_LO12:
    case BFD_RELOC_AARCH64_LD32_GOT_LO12_NC:
    case BFD_RELOC_AARCH64_LD64_GOT_LO12_NC:
    case BFD_RELOC_AARCH64_LDST128_LO12:
    case BFD_RELOC_AARCH64_LDST16_LO12:
    case BFD_RELOC_AARCH64_LDST32_LO12:
    case BFD_RELOC_AARCH64_LDST64_LO12:
    case BFD_RELOC_AARCH64_LDST8_LO12:
    case BFD_RELOC_AARCH64_TLSDESC_ADD:
    case BFD_RELOC_AARCH64_TLSDESC_ADD_LO12:
    case BFD_RELOC_AARCH64_TLSDESC_LD32_LO12_NC:
    case BFD_RELOC_AARCH64_TLSDESC_LD64_LO12:
    case BFD_RELOC_AARCH64_TLSDESC_LDR:
    case BFD_RELOC_AARCH64_TLSGD_ADD_LO12_NC:
    case BFD_RELOC_AARCH64_TLSIE_LD32_GOTTPREL_LO12_NC:
    case BFD_RELOC_AARCH64_TLSIE_LD64_GOTTPREL_LO12_NC:
    case BFD_RELOC_AARCH64_TLSLE_ADD_TPREL_LO12_NC:
      value = PG_OFFSET (value + addend);
      break;

    case BFD_RELOC_AARCH64_TLSLE_ADD_TPREL_LO12:
      value = value + addend;
      break;

    case BFD_RELOC_AARCH64_TLSIE_MOVW_GOTTPREL_G1:
    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:
      /* Mask off low 12bits, keep all other high bits, so that the later
	 generic code could check whehter there is overflow.  */
      value = (value + addend) & ~(bfd_vma) 0xfff;
      break;

    case BFD_RELOC_AARCH64_TLSIE_MOVW_GOTTPREL_G0_NC:
    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
      && (abfd->flags & DYNAMIC) == 0
      && bfd_get_flavour (info->output_bfd) == bfd_target_elf_flavour)
    elf_tdata (info->output_bfd)->has_gnu_symbols |= elf_gnu_symbol_ifunc;

  return TRUE;
}

/* Support for core dump NOTE sections.

   note->descsz should be the size of elf_prstatus, defined in 
   usr/include/linux/elfcore.h.  The size is 352 in ILP32 mode
   and 392 in LP64 mode. elf_tdata (abfd)->core->signal is set from the
   pr_cursig field of elf_prstatus which is at an offset of 12 in the
   elf_prstatus structure in both ILP32 and LP64 modes.

   elf_tdata (abfd)->core->lwpid is set from the pr_pid field of the
   elf_prstatus structure.  It has an offset of 24 in ILP32 mode and
   32 in LP64 mode due to two long fields in the structure that are in
   front of the pr_pid field.  */

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 352:	/* sizeof(struct elf_prstatus) on Linux/aarch64 ilp32.  */
	/* 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 + 24);

	/* pr_reg */
	offset = 72;
	size = 272;

	break;

      case 392:	/* sizeof(struct elf_prstatus) on Linux/aarch64.  */
	/* 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 124:         /* sizeof(struct elf_prpsinfo) on Linux/aarch64 ilp32.  */
      elf_tdata (abfd)->core->pid = bfd_get_32 (abfd, note->descdata + 12);
      elf_tdata (abfd)->core->program
	= _bfd_elfcore_strndup (abfd, note->descdata + 28, 16);
      elf_tdata (abfd)->core->command
	= _bfd_elfcore_strndup (abfd, note->descdata + 44, 80);
      break;

    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);
      break;
    }

  /* 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));
      }
    }
}