old-cross-binutils/bfd/elfxx-aarch64.c
Marcus Shawcroft 4106101c44 [AArch64] Workaround for Cortex A53 erratum 843419
Some early revisions of the Cortex-A53 have an erratum (843419).  The
details of the erratum are quite complex and involve dynamic
conditions.  For the purposes of the workaround we have simplified the
static conditions to an ADRP in the last two instructions of a 4KByte
page, followed within four instructions by a load/store dependent on
the ADRP.

This patch adds support to conservatively scan for and workaround
Cortex A53 erratum 843419.  There are two different workaround
strategies used.  The first is to rewrite ADRP instructions which form
part of an erratum sequence with an ADR instruction.  In situations
where the ADR provides insufficient offset the dependent load or store
instruction from the sequence is moved to a stub section and branches
are inserted from the original sequence to the relocated instruction
and back again.

Stub section sizes are rounded up to a multiple of 4096 in order to
ensure that the act of inserting work around stubs does not create
more errata sequences.

Workaround stubs are always inserted into the stub section associated
with the input section containing the erratum sequence.  This ensures
that the fully relocated form of the veneered load store instruction
is available at the point in time when the stub section is written.
2015-04-01 13:16:38 +01:00

595 lines
17 KiB
C

/* AArch64-specific support for ELF.
Copyright (C) 2009-2015 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_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_TLSDESC_LD_PREL19:
case BFD_RELOC_AARCH64_LD_LO19_PCREL:
case BFD_RELOC_AARCH64_GOT_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_TLSDESC_ADR_PREL21:
case BFD_RELOC_AARCH64_TLSGD_ADR_PREL21:
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_G0:
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_TLSLE_MOVW_TPREL_G0_NC:
case BFD_RELOC_AARCH64_TLSLE_MOVW_TPREL_G1_NC:
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_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_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:
/* 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_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));
}
}
}