[gdb] Fix tsan warning: signal handler spoils errno

[binutils-gdb.git] / gas / config / tc-tilegx.c

/* tc-tilegx.c -- Assemble for a Tile-Gx chip.
   Copyright (C) 2011-2024 Free Software Foundation, Inc.

   This file is part of GAS, the GNU Assembler.

   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; if not, write to the Free Software
   Foundation, Inc., 51 Franklin Street - Fifth Floor, Boston,
   MA 02110-1301, USA.  */

#include "as.h"
#include "subsegs.h"

#include "elf/tilegx.h"
#include "opcode/tilegx.h"

#include "dwarf2dbg.h"
#include "dw2gencfi.h"

#include "safe-ctype.h"


/* Special registers.  */
#define TREG_IDN0     57
#define TREG_IDN1     58
#define TREG_UDN0     59
#define TREG_UDN1     60
#define TREG_UDN2     61
#define TREG_UDN3     62
#define TREG_ZERO     63


/* Generic assembler global variables which must be defined by all
   targets.  */

/* The dwarf2 data alignment, adjusted for 32 or 64 bit.  */
int tilegx_cie_data_alignment;

/* Characters which always start a comment.  */
const char comment_chars[] = "#";

/* Characters which start a comment at the beginning of a line.  */
const char line_comment_chars[] = "#";

/* Characters which may be used to separate multiple commands on a
   single line.  */
const char line_separator_chars[] = ";";

/* Characters which are used to indicate an exponent in a floating
   point number.  */
const char EXP_CHARS[] = "eE";

/* Characters which mean that a number is a floating point constant,
   as in 0d1.0.  */
const char FLT_CHARS[] = "rRsSfFdDxXpP";

/* Either 32 or 64.  */
static int tilegx_arch_size = 64;


const char *
tilegx_target_format (void)
{
    if (target_big_endian) {
        return tilegx_arch_size == 64 ? "elf64-tilegx-be" : "elf32-tilegx-be";
    } else {
        return tilegx_arch_size == 64 ? "elf64-tilegx-le" : "elf32-tilegx-le";
    }
}


#define OPTION_32 (OPTION_MD_BASE + 0)
#define OPTION_64 (OPTION_MD_BASE + 1)
#define OPTION_EB (OPTION_MD_BASE + 2)
#define OPTION_EL (OPTION_MD_BASE + 3)

const char md_shortopts[] = "VQ:";

const struct option md_longopts[] =
{
  {"32", no_argument, NULL, OPTION_32},
  {"64", no_argument, NULL, OPTION_64},
  {"EB", no_argument, NULL, OPTION_EB },
  {"EL", no_argument, NULL, OPTION_EL },
  {NULL, no_argument, NULL, 0}
};

const size_t md_longopts_size = sizeof (md_longopts);

int
md_parse_option (int c, const char *arg ATTRIBUTE_UNUSED)
{
  switch (c)
    {
      /* -Qy, -Qn: SVR4 arguments controlling whether a .comment section
         should be emitted or not.  FIXME: Not implemented.  */
    case 'Q':
      break;

      /* -V: SVR4 argument to print version ID.  */
    case 'V':
      print_version_id ();
      break;

    case OPTION_32:
      tilegx_arch_size = 32;
      break;

    case OPTION_64:
      tilegx_arch_size = 64;
      break;

    case OPTION_EB:
      target_big_endian = 1;
      break;

    case OPTION_EL:
      target_big_endian = 0;
      break;

    default:
      return 0;
    }

  return 1;
}

void
md_show_usage (FILE *stream)
{
  fprintf (stream, _("\
  -Q                      ignored\n\
  -V                      print assembler version number\n\
  -EB/-EL                 generate big-endian/little-endian code\n\
  --32/--64               generate 32bit/64bit code\n"));
}


/* Extra expression types.  */

#define O_hw0                   O_md1
#define O_hw1                   O_md2
#define O_hw2                   O_md3
#define O_hw3                   O_md4
#define O_hw0_last              O_md5
#define O_hw1_last              O_md6
#define O_hw2_last              O_md7
#define O_hw0_got               O_md8
#define O_hw0_last_got          O_md9
#define O_hw1_last_got          O_md10
#define O_plt                   O_md11
#define O_hw0_tls_gd            O_md12
#define O_hw0_last_tls_gd       O_md13
#define O_hw1_last_tls_gd       O_md14
#define O_hw0_tls_ie            O_md15
#define O_hw0_last_tls_ie       O_md16
#define O_hw1_last_tls_ie       O_md17
#define O_hw0_tls_le            O_md18
#define O_hw0_last_tls_le       O_md19
#define O_hw1_last_tls_le       O_md20
#define O_tls_gd_call           O_md21
#define O_tls_gd_add            O_md22
#define O_tls_ie_load           O_md23
#define O_tls_add               O_md24
#define O_hw0_plt               O_md25
#define O_hw1_plt               O_md26
#define O_hw1_last_plt          O_md27
#define O_hw2_last_plt          O_md28

static htab_t special_operator_hash;

/* Hash tables for instruction mnemonic lookup.  */
static htab_t op_hash;

/* Hash table for spr lookup.  */
static htab_t spr_hash;

/* True temporarily while parsing an SPR expression. This changes the
 * namespace to include SPR names.  */
static int parsing_spr;

/* Are we currently inside `{ ... }'?  */
static int inside_bundle;

struct tilegx_instruction
{
  const struct tilegx_opcode *opcode;
  tilegx_pipeline pipe;
  expressionS operand_values[TILEGX_MAX_OPERANDS];
};

/* This keeps track of the current bundle being built up.  */
static struct tilegx_instruction current_bundle[TILEGX_MAX_INSTRUCTIONS_PER_BUNDLE];

/* Index in current_bundle for the next instruction to parse.  */
static int current_bundle_index;

/* Allow 'r63' in addition to 'zero', etc. Normally we disallow this as
   'zero' is not a real register, so using it accidentally would be a
   nasty bug. For other registers, such as 'sp', code using multiple names
   for the same physical register is excessively confusing.

   The '.require_canonical_reg_names' pseudo-op turns this error on,
   and the '.no_require_canonical_reg_names' pseudo-op turns this off.
   By default the error is on.  */
static int require_canonical_reg_names;

/* Allow bundles that do undefined or suspicious things like write
   two different values to the same register at the same time.

   The '.no_allow_suspicious_bundles' pseudo-op turns this error on,
   and the '.allow_suspicious_bundles' pseudo-op turns this off.  */
static int allow_suspicious_bundles;


/* A hash table of main processor registers, mapping each register name
   to its index.

   Furthermore, if the register number is greater than the number
   of registers for that processor, the user used an illegal alias
   for that register (e.g. r63 instead of zero), so we should generate
   a warning. The attempted register number can be found by clearing
   NONCANONICAL_REG_NAME_FLAG.  */
static htab_t main_reg_hash;


/* We cannot unambiguously store a 0 in a hash table and look it up,
   so we OR in this flag to every canonical register.  */
#define CANONICAL_REG_NAME_FLAG    0x1000

/* By default we disallow register aliases like r63, but we record
   them in the hash table in case the .no_require_canonical_reg_names
   directive is used. Noncanonical names have this value added to them.  */
#define NONCANONICAL_REG_NAME_FLAG 0x2000

/* Discards flags for register hash table entries and returns the
   reg number.  */
#define EXTRACT_REGNO(p) ((p) & 63)

/* This function is called once, at assembler startup time.  It should
   set up all the tables, etc., that the MD part of the assembler will
   need.  */

void
md_begin (void)
{
  const struct tilegx_opcode *op;
  int i;
  int mach = (tilegx_arch_size == 64) ? bfd_mach_tilegx : bfd_mach_tilegx32;

  if (! bfd_set_arch_mach (stdoutput, bfd_arch_tilegx, mach))
    as_warn (_("Could not set architecture and machine"));

  /* Guarantee text section is aligned.  */
  bfd_set_section_alignment (text_section,
                             TILEGX_LOG2_BUNDLE_ALIGNMENT_IN_BYTES);

  require_canonical_reg_names = 1;
  allow_suspicious_bundles = 0;
  current_bundle_index = 0;
  inside_bundle = 0;

  tilegx_cie_data_alignment = (tilegx_arch_size == 64 ? -8 : -4);

  /* Initialize special operator hash table.  */
  special_operator_hash = str_htab_create ();
#define INSERT_SPECIAL_OP(name)                                 \
  str_hash_insert (special_operator_hash, #name, (void *) O_##name, 0)

  INSERT_SPECIAL_OP (hw0);
  INSERT_SPECIAL_OP (hw1);
  INSERT_SPECIAL_OP (hw2);
  INSERT_SPECIAL_OP (hw3);
  INSERT_SPECIAL_OP (hw0_last);
  INSERT_SPECIAL_OP (hw1_last);
  INSERT_SPECIAL_OP (hw2_last);
  /* hw3_last is a convenience alias for the equivalent hw3.  */
  str_hash_insert (special_operator_hash, "hw3_last", (void *) O_hw3, 0);
  INSERT_SPECIAL_OP (hw0_got);
  INSERT_SPECIAL_OP (hw0_last_got);
  INSERT_SPECIAL_OP (hw1_last_got);
  INSERT_SPECIAL_OP(plt);
  INSERT_SPECIAL_OP (hw0_tls_gd);
  INSERT_SPECIAL_OP (hw0_last_tls_gd);
  INSERT_SPECIAL_OP (hw1_last_tls_gd);
  INSERT_SPECIAL_OP (hw0_tls_ie);
  INSERT_SPECIAL_OP (hw0_last_tls_ie);
  INSERT_SPECIAL_OP (hw1_last_tls_ie);
  INSERT_SPECIAL_OP (hw0_tls_le);
  INSERT_SPECIAL_OP (hw0_last_tls_le);
  INSERT_SPECIAL_OP (hw1_last_tls_le);
  INSERT_SPECIAL_OP (tls_gd_call);
  INSERT_SPECIAL_OP (tls_gd_add);
  INSERT_SPECIAL_OP (tls_ie_load);
  INSERT_SPECIAL_OP (tls_add);
  INSERT_SPECIAL_OP (hw0_plt);
  INSERT_SPECIAL_OP (hw1_plt);
  INSERT_SPECIAL_OP (hw1_last_plt);
  INSERT_SPECIAL_OP (hw2_last_plt);
#undef INSERT_SPECIAL_OP

  /* Initialize op_hash hash table.  */
  op_hash = str_htab_create ();
  for (op = &tilegx_opcodes[0]; op->name != NULL; op++)
    if (str_hash_insert (op_hash, op->name, op, 0) != NULL)
      as_fatal (_("duplicate %s"), op->name);

  /* Initialize the spr hash table.  */
  parsing_spr = 0;
  spr_hash = str_htab_create ();
  for (i = 0; i < tilegx_num_sprs; i++)
    str_hash_insert (spr_hash, tilegx_sprs[i].name, &tilegx_sprs[i], 0);

  /* Set up the main_reg_hash table. We use this instead of
     creating a symbol in the register section to avoid ambiguities
     with labels that have the same names as registers.  */
  main_reg_hash = str_htab_create ();
  for (i = 0; i < TILEGX_NUM_REGISTERS; i++)
    {
      char buf[64];

      str_hash_insert (main_reg_hash, tilegx_register_names[i],
                       (void *) (long) (i | CANONICAL_REG_NAME_FLAG), 0);

      /* See if we should insert a noncanonical alias, like r63.  */
      sprintf (buf, "r%d", i);
      if (strcmp (buf, tilegx_register_names[i]) != 0)
        str_hash_insert (main_reg_hash, xstrdup (buf),
                         (void *) (long) (i | NONCANONICAL_REG_NAME_FLAG), 0);
    }
}

#define BUNDLE_TEMPLATE_MASK(p0, p1, p2) \
  ((p0) | ((p1) << 8) | ((p2) << 16))
#define BUNDLE_TEMPLATE(p0, p1, p2) \
  { { (p0), (p1), (p2) }, \
     BUNDLE_TEMPLATE_MASK(1 << (p0), 1 << (p1), (1 << (p2))) \
  }

#define NO_PIPELINE TILEGX_NUM_PIPELINE_ENCODINGS

struct bundle_template
{
  tilegx_pipeline pipe[TILEGX_MAX_INSTRUCTIONS_PER_BUNDLE];
  unsigned int pipe_mask;
};

static const struct bundle_template bundle_templates[] =
{
  /* In Y format we must always have something in Y2, since it has
     no fnop, so this conveys that Y2 must always be used.  */
  BUNDLE_TEMPLATE(TILEGX_PIPELINE_Y0, TILEGX_PIPELINE_Y2, NO_PIPELINE),
  BUNDLE_TEMPLATE(TILEGX_PIPELINE_Y1, TILEGX_PIPELINE_Y2, NO_PIPELINE),
  BUNDLE_TEMPLATE(TILEGX_PIPELINE_Y2, TILEGX_PIPELINE_Y0, NO_PIPELINE),
  BUNDLE_TEMPLATE(TILEGX_PIPELINE_Y2, TILEGX_PIPELINE_Y1, NO_PIPELINE),

  /* Y format has three instructions.  */
  BUNDLE_TEMPLATE(TILEGX_PIPELINE_Y0,TILEGX_PIPELINE_Y1,TILEGX_PIPELINE_Y2),
  BUNDLE_TEMPLATE(TILEGX_PIPELINE_Y0,TILEGX_PIPELINE_Y2,TILEGX_PIPELINE_Y1),
  BUNDLE_TEMPLATE(TILEGX_PIPELINE_Y1,TILEGX_PIPELINE_Y0,TILEGX_PIPELINE_Y2),
  BUNDLE_TEMPLATE(TILEGX_PIPELINE_Y1,TILEGX_PIPELINE_Y2,TILEGX_PIPELINE_Y0),
  BUNDLE_TEMPLATE(TILEGX_PIPELINE_Y2,TILEGX_PIPELINE_Y0,TILEGX_PIPELINE_Y1),
  BUNDLE_TEMPLATE(TILEGX_PIPELINE_Y2,TILEGX_PIPELINE_Y1,TILEGX_PIPELINE_Y0),

  /* X format has only two instructions.  */
  BUNDLE_TEMPLATE(TILEGX_PIPELINE_X0, TILEGX_PIPELINE_X1, NO_PIPELINE),
  BUNDLE_TEMPLATE(TILEGX_PIPELINE_X1, TILEGX_PIPELINE_X0, NO_PIPELINE)
};


static void
prepend_nop_to_bundle (tilegx_mnemonic mnemonic)
{
  memmove (&current_bundle[1], &current_bundle[0],
           current_bundle_index * sizeof current_bundle[0]);
  current_bundle[0].opcode = &tilegx_opcodes[mnemonic];
  ++current_bundle_index;
}

static tilegx_bundle_bits
insert_operand (tilegx_bundle_bits bits,
                const struct tilegx_operand *operand,
                int operand_value,
                const char *file,
                unsigned lineno)
{
  /* Range-check the immediate.  */
  int num_bits = operand->num_bits;

  operand_value >>= operand->rightshift;

  if (bfd_check_overflow (operand->is_signed
                          ? complain_overflow_signed
                          : complain_overflow_unsigned,
                          num_bits,
                          0,
                          bfd_arch_bits_per_address (stdoutput),
                          operand_value)
      != bfd_reloc_ok)
    {
      offsetT min, max;
      if (operand->is_signed)
        {
          min = -(1 << (num_bits - 1));
          max = (1 << (num_bits - 1)) - 1;
        }
      else
        {
          min = 0;
          max = (1 << num_bits) - 1;
        }
      as_bad_value_out_of_range (_("operand"), operand_value, min, max,
                                 file, lineno);
    }

  /* Write out the bits for the immediate.  */
  return bits | operand->insert (operand_value);
}


static int
apply_special_operator (operatorT op, offsetT num, const char *file,
                        unsigned lineno)
{
  int ret;
  int check_shift = -1;

  switch (op)
    {
    case O_hw0_last:
      check_shift = 0;
      /* Fall through.  */
    case O_hw0:
      ret = (signed short)num;
      break;

    case O_hw1_last:
      check_shift = 16;
      /* Fall through.  */
    case O_hw1:
      ret = (signed short)(num >> 16);
      break;

    case O_hw2_last:
      check_shift = 32;
      /* Fall through.  */
    case O_hw2:
      ret = (signed short)(num >> 32);
      break;

    case O_hw3:
      ret = (signed short)(num >> 48);
      break;

    default:
      abort ();
      break;
    }

  if (check_shift >= 0 && ret != (num >> check_shift))
    {
      as_bad_value_out_of_range (_("operand"), num,
                                 ~0ULL << (check_shift + 16 - 1),
                                 ~0ULL >> (64 - (check_shift + 16 - 1)),
                                 file, lineno);
    }

  return ret;
}

static tilegx_bundle_bits
emit_tilegx_instruction (tilegx_bundle_bits bits,
                         int num_operands,
                         const unsigned char *operands,
                         expressionS *operand_values,
                         char *bundle_start)
{
  int i;

  for (i = 0; i < num_operands; i++)
    {
      const struct tilegx_operand *operand =
        &tilegx_operands[operands[i]];
      expressionS *operand_exp = &operand_values[i];
      int is_pc_relative = operand->is_pc_relative;

      if (operand_exp->X_op == O_register
          || (operand_exp->X_op == O_constant && !is_pc_relative))
        {
          /* We know what the bits are right now, so insert them.  */
          bits = insert_operand (bits, operand, operand_exp->X_add_number,
                                 NULL, 0);
        }
      else
        {
          bfd_reloc_code_real_type reloc = operand->default_reloc;
          expressionS subexp;
          int die = 0, use_subexp = 0, require_symbol = 0;
          fixS *fixP;

          /* Take an expression like hw0(x) and turn it into x with
             a different reloc type.  */
          switch (operand_exp->X_op)
            {
#define HANDLE_OP16(suffix)                                     \
              switch (reloc)                                    \
                {                                               \
                case BFD_RELOC_TILEGX_IMM16_X0_HW0_LAST:        \
                  reloc = BFD_RELOC_TILEGX_IMM16_X0_##suffix;   \
                  break;                                        \
                case BFD_RELOC_TILEGX_IMM16_X1_HW0_LAST:        \
                  reloc = BFD_RELOC_TILEGX_IMM16_X1_##suffix;   \
                  break;                                        \
                default:                                        \
                  die = 1;                                      \
                  break;                                        \
                }                                               \
              use_subexp = 1

            case O_hw0:
              HANDLE_OP16 (HW0);
              break;

            case O_hw1:
              HANDLE_OP16 (HW1);
              break;

            case O_hw2:
              HANDLE_OP16 (HW2);
              break;

            case O_hw3:
              HANDLE_OP16 (HW3);
              break;

            case O_hw0_last:
              HANDLE_OP16 (HW0_LAST);
              break;

            case O_hw1_last:
              HANDLE_OP16 (HW1_LAST);
              break;

            case O_hw2_last:
              HANDLE_OP16 (HW2_LAST);
              break;

            case O_hw0_got:
              HANDLE_OP16 (HW0_GOT);
              require_symbol = 1;
              break;

            case O_hw0_last_got:
              HANDLE_OP16 (HW0_LAST_GOT);
              require_symbol = 1;
              break;

            case O_hw1_last_got:
              HANDLE_OP16 (HW1_LAST_GOT);
              require_symbol = 1;
              break;

            case O_hw0_tls_gd:
              HANDLE_OP16 (HW0_TLS_GD);
              require_symbol = 1;
              break;

            case O_hw0_last_tls_gd:
              HANDLE_OP16 (HW0_LAST_TLS_GD);
              require_symbol = 1;
              break;

            case O_hw1_last_tls_gd:
              HANDLE_OP16 (HW1_LAST_TLS_GD);
              require_symbol = 1;
              break;

            case O_hw0_tls_ie:
              HANDLE_OP16 (HW0_TLS_IE);
              require_symbol = 1;
              break;

            case O_hw0_last_tls_ie:
              HANDLE_OP16 (HW0_LAST_TLS_IE);
              require_symbol = 1;
              break;

            case O_hw1_last_tls_ie:
              HANDLE_OP16 (HW1_LAST_TLS_IE);
              require_symbol = 1;
              break;

            case O_hw0_tls_le:
              HANDLE_OP16 (HW0_TLS_LE);
              require_symbol = 1;
              break;

            case O_hw0_last_tls_le:
              HANDLE_OP16 (HW0_LAST_TLS_LE);
              require_symbol = 1;
              break;

            case O_hw1_last_tls_le:
              HANDLE_OP16 (HW1_LAST_TLS_LE);
              require_symbol = 1;
              break;

            case O_hw0_plt:
              HANDLE_OP16 (HW0_PLT_PCREL);
              break;

            case O_hw1_plt:
              HANDLE_OP16 (HW1_PLT_PCREL);
              break;

            case O_hw1_last_plt:
              HANDLE_OP16 (HW1_LAST_PLT_PCREL);
              break;

            case O_hw2_last_plt:
              HANDLE_OP16 (HW2_LAST_PLT_PCREL);
              break;

#undef HANDLE_OP16

            case O_plt:
              switch (reloc)
                {
                case BFD_RELOC_TILEGX_JUMPOFF_X1:
                  reloc = BFD_RELOC_TILEGX_JUMPOFF_X1_PLT;
                  break;
                default:
                  die = 1;
                  break;
                }
              use_subexp = 1;
              require_symbol = 1;
              break;

            case O_tls_gd_call:
              switch (reloc)
                {
                case BFD_RELOC_TILEGX_JUMPOFF_X1:
                  reloc = BFD_RELOC_TILEGX_TLS_GD_CALL;
                  break;
                default:
                  die = 1;
                  break;
                }
              use_subexp = 1;
              require_symbol = 1;
              break;

            case O_tls_gd_add:
              switch (reloc)
                {
                case BFD_RELOC_TILEGX_IMM8_X0:
                  reloc = BFD_RELOC_TILEGX_IMM8_X0_TLS_GD_ADD;
                  break;
                case BFD_RELOC_TILEGX_IMM8_X1:
                  reloc = BFD_RELOC_TILEGX_IMM8_X1_TLS_GD_ADD;
                  break;
                case BFD_RELOC_TILEGX_IMM8_Y0:
                  reloc = BFD_RELOC_TILEGX_IMM8_Y0_TLS_GD_ADD;
                  break;
                case BFD_RELOC_TILEGX_IMM8_Y1:
                  reloc = BFD_RELOC_TILEGX_IMM8_Y1_TLS_GD_ADD;
                  break;
                default:
                  die = 1;
                  break;
                }
              use_subexp = 1;
              require_symbol = 1;
              break;

            case O_tls_ie_load:
              switch (reloc)
                {
                case BFD_RELOC_TILEGX_IMM8_X1:
                  reloc = BFD_RELOC_TILEGX_TLS_IE_LOAD;
                  break;
                default:
                  die = 1;
                  break;
                }
              use_subexp = 1;
              require_symbol = 1;
              break;

            case O_tls_add:
              switch (reloc)
                {
                case BFD_RELOC_TILEGX_IMM8_X0:
                  reloc = BFD_RELOC_TILEGX_IMM8_X0_TLS_ADD;
                  break;
                case BFD_RELOC_TILEGX_IMM8_X1:
                  reloc = BFD_RELOC_TILEGX_IMM8_X1_TLS_ADD;
                  break;
                case BFD_RELOC_TILEGX_IMM8_Y0:
                  reloc = BFD_RELOC_TILEGX_IMM8_Y0_TLS_ADD;
                  break;
                case BFD_RELOC_TILEGX_IMM8_Y1:
                  reloc = BFD_RELOC_TILEGX_IMM8_Y1_TLS_ADD;
                  break;
                default:
                  die = 1;
                  break;
                }
              use_subexp = 1;
              require_symbol = 1;
              break;

            default:
              /* Do nothing.  */
              break;
            }

          if (die)
            {
              as_bad (_("Invalid operator for operand."));
            }
          else if (use_subexp)
            {
              expressionS *sval = NULL;
              /* Now that we've changed the reloc, change ha16(x) into x,
                 etc.  */

              if (symbol_symbolS (operand_exp->X_add_symbol))
                sval = symbol_get_value_expression (operand_exp->X_add_symbol);
              if (sval && sval->X_md)
                {
                  /* HACK: We used X_md to mark this symbol as a fake wrapper
                     around a real expression. To unwrap it, we just grab its
                     value here.  */
                  operand_exp = sval;

                  if (require_symbol)
                    {
                      /* Look at the expression, and reject it if it's not a
                         plain symbol.  */
                      if (operand_exp->X_op != O_symbol
                          || operand_exp->X_add_number != 0)
                        as_bad (_("Operator may only be applied to symbols."));
                    }
                }
              else
                {
                  /* The value of this expression is an actual symbol, so
                     turn that into an expression.  */
                  memset (&subexp, 0, sizeof subexp);
                  subexp.X_op = O_symbol;
                  subexp.X_add_symbol = operand_exp->X_add_symbol;
                  operand_exp = &subexp;
                }
            }

          /* Create a fixup to handle this later.  */
          fixP = fix_new_exp (frag_now,
                              bundle_start - frag_now->fr_literal,
                              (operand->num_bits + 7) >> 3,
                              operand_exp,
                              is_pc_relative,
                              reloc);
          fixP->tc_fix_data = operand;

          /* Don't do overflow checking if we are applying a function like
             ha16.  */
          fixP->fx_no_overflow |= use_subexp;
        }
    }
  return bits;
}


/* Detects and complains if two instructions in current_bundle write
   to the same register, either implicitly or explicitly, or if a
   read-only register is written.  */
static void
check_illegal_reg_writes (void)
{
  uint64_t all_regs_written = 0;
  int j;

  for (j = 0; j < current_bundle_index; j++)
    {
      const struct tilegx_instruction *instr = &current_bundle[j];
      int k;
      uint64_t regs =
        (uint64_t) 1 << instr->opcode->implicitly_written_register;
      uint64_t conflict;

      for (k = 0; k < instr->opcode->num_operands; k++)
        {
          const struct tilegx_operand *operand =
            &tilegx_operands[instr->opcode->operands[instr->pipe][k]];

          if (operand->is_dest_reg)
            {
              int regno = instr->operand_values[k].X_add_number;
              uint64_t mask = (uint64_t) 1 << regno;

              if ((mask & (  ((uint64_t) 1 << TREG_IDN1)
                           | ((uint64_t) 1 << TREG_UDN1)
                           | ((uint64_t) 1 << TREG_UDN2)
                           | ((uint64_t) 1 << TREG_UDN3))) != 0
                  && !allow_suspicious_bundles)
                {
                  as_bad (_("Writes to register '%s' are not allowed."),
                          tilegx_register_names[regno]);
                }

              regs |= mask;
            }
        }

      /* Writing to the zero register doesn't count.  */
      regs &= ~((uint64_t) 1 << TREG_ZERO);

      conflict = all_regs_written & regs;
      if (conflict != 0 && !allow_suspicious_bundles)
        {
          /* Find which register caused the conflict.  */
          const char *conflicting_reg_name = "???";
          int i;

          for (i = 0; i < TILEGX_NUM_REGISTERS; i++)
            {
              if (((conflict >> i) & 1) != 0)
                {
                  conflicting_reg_name = tilegx_register_names[i];
                  break;
                }
            }

          as_bad (_("Two instructions in the same bundle both write "
                    "to register %s, which is not allowed."),
                  conflicting_reg_name);
        }

      all_regs_written |= regs;
    }
}


static void
tilegx_flush_bundle (void)
{
  unsigned i;
  int j;
  addressT addr_mod;
  unsigned compatible_pipes;
  const struct bundle_template *match;
  char *f;

  inside_bundle = 0;

  switch (current_bundle_index)
    {
    case 0:
      /* No instructions.  */
      return;
    case 1:
      if (current_bundle[0].opcode->can_bundle)
        {
          /* Simplify later logic by adding an explicit fnop.  */
          prepend_nop_to_bundle (TILEGX_OPC_FNOP);
        }
      else
        {
          /* This instruction cannot be bundled with anything else.
             Prepend an explicit 'nop', rather than an 'fnop', because
             fnops can be replaced by later binary-processing tools while
             nops cannot.  */
          prepend_nop_to_bundle (TILEGX_OPC_NOP);
        }
      break;
    default:
      if (!allow_suspicious_bundles)
        {
          /* Make sure all instructions can be bundled with other
             instructions.  */
          const struct tilegx_opcode *cannot_bundle = NULL;
          bool seen_non_nop = false;

          for (j = 0; j < current_bundle_index; j++)
            {
              const struct tilegx_opcode *op = current_bundle[j].opcode;

              if (!op->can_bundle && cannot_bundle == NULL)
                cannot_bundle = op;
              else if (op->mnemonic != TILEGX_OPC_NOP
                       && op->mnemonic != TILEGX_OPC_INFO
                       && op->mnemonic != TILEGX_OPC_INFOL)
                seen_non_nop = true;
            }

          if (cannot_bundle != NULL && seen_non_nop)
            {
              current_bundle_index = 0;
              as_bad (_("'%s' may not be bundled with other instructions."),
                      cannot_bundle->name);
              return;
            }
        }
      break;
    }

  compatible_pipes =
    BUNDLE_TEMPLATE_MASK(current_bundle[0].opcode->pipes,
                         current_bundle[1].opcode->pipes,
                         (current_bundle_index == 3
                          ? current_bundle[2].opcode->pipes
                          : (1 << NO_PIPELINE)));

  /* Find a template that works, if any.  */
  match = NULL;
  for (i = 0; i < sizeof bundle_templates / sizeof bundle_templates[0]; i++)
    {
      const struct bundle_template *b = &bundle_templates[i];
      if ((b->pipe_mask & compatible_pipes) == b->pipe_mask)
        {
          match = b;
          break;
        }
    }

  if (match == NULL)
    {
      current_bundle_index = 0;
      as_bad (_("Invalid combination of instructions for bundle."));
      return;
    }

  /* If the section seems to have no alignment set yet, go ahead and
     make it large enough to hold code.  */
  if (bfd_section_alignment (now_seg) == 0)
    bfd_set_section_alignment (now_seg,
                               TILEGX_LOG2_BUNDLE_ALIGNMENT_IN_BYTES);

  for (j = 0; j < current_bundle_index; j++)
    current_bundle[j].pipe = match->pipe[j];

  if (current_bundle_index == 2 && !tilegx_is_x_pipeline (match->pipe[0]))
    {
      /* We are in Y mode with only two instructions, so add an FNOP.  */
      prepend_nop_to_bundle (TILEGX_OPC_FNOP);

      /* Figure out what pipe the fnop must be in via arithmetic.
       * p0 + p1 + p2 must sum to the sum of TILEGX_PIPELINE_Y[012].  */
      current_bundle[0].pipe =
        (tilegx_pipeline)((TILEGX_PIPELINE_Y0
                           + TILEGX_PIPELINE_Y1
                           + TILEGX_PIPELINE_Y2) -
                          (current_bundle[1].pipe + current_bundle[2].pipe));
    }

  check_illegal_reg_writes ();

  f = frag_more (TILEGX_BUNDLE_SIZE_IN_BYTES);

  /* Check to see if this bundle is at an offset that is a multiple of 8-bytes
     from the start of the frag.  */
  addr_mod = frag_now_fix () & (TILEGX_BUNDLE_ALIGNMENT_IN_BYTES - 1);
  if (frag_now->has_code && frag_now->insn_addr != addr_mod)
    as_bad (_("instruction address is not a multiple of 8"));
  frag_now->insn_addr = addr_mod;
  frag_now->has_code = 1;

  tilegx_bundle_bits bits = 0;
  for (j = 0; j < current_bundle_index; j++)
    {
      struct tilegx_instruction *instr = &current_bundle[j];
      tilegx_pipeline pipeline = instr->pipe;
      const struct tilegx_opcode *opcode = instr->opcode;

      bits |= emit_tilegx_instruction (opcode->fixed_bit_values[pipeline],
                                       opcode->num_operands,
                                       &opcode->operands[pipeline][0],
                                       instr->operand_values,
                                       f);
    }

  number_to_chars_littleendian (f, bits, 8);
  current_bundle_index = 0;

  /* Emit DWARF2 debugging information.  */
  dwarf2_emit_insn (TILEGX_BUNDLE_SIZE_IN_BYTES);
}


/* Extend the expression parser to handle hw0(label), etc.
   as well as SPR names when in the context of parsing an SPR.  */

int
tilegx_parse_name (char *name, expressionS *e, char *nextcharP)
{
  operatorT op = O_illegal;

  if (parsing_spr)
    {
      void* val = str_hash_find (spr_hash, name);
      if (val == NULL)
        return 0;

      memset (e, 0, sizeof *e);
      e->X_op = O_constant;
      e->X_add_number = ((const struct tilegx_spr *)val)->number;
      return 1;
    }

  if (*nextcharP != '(')
    {
      /* hw0, etc. not followed by a paren is just a label with that name.  */
      return 0;
    }
  else
    {
      /* Look up the operator in our table.  */
      void* val = str_hash_find (special_operator_hash, name);
      if (val == 0)
        return 0;
      op = (operatorT)(long)val;
    }

  /* Restore old '(' and skip it.  */
  *input_line_pointer = '(';
  ++input_line_pointer;

  expression (e);

  if (*input_line_pointer != ')')
    {
      as_bad (_("Missing ')'"));
      *nextcharP = *input_line_pointer;
      return 0;
    }
  /* Skip ')'.  */
  ++input_line_pointer;

  if (e->X_op == O_register || e->X_op == O_absent)
    {
      as_bad (_("Invalid expression."));
      e->X_op = O_constant;
      e->X_add_number = 0;
    }
  else
    {
      /* Wrap subexpression with a unary operator.  */
      symbolS *sym = make_expr_symbol (e);

      if (sym != e->X_add_symbol)
        {
          /* HACK: mark this symbol as a temporary wrapper around a proper
             expression, so we can unwrap it later once we have communicated
             the relocation type.  */
          symbol_get_value_expression (sym)->X_md = 1;
        }

      memset (e, 0, sizeof *e);
      e->X_op = op;
      e->X_add_symbol = sym;
      e->X_add_number = 0;
    }

  *nextcharP = *input_line_pointer;
  return 1;
}


/* Parses an expression which must be a register name.  */

static void
parse_reg_expression (expressionS* expression)
{
  char *regname;
  char terminating_char;
  void *pval;
  int regno_and_flags;
  int regno;

  /* Zero everything to make sure we don't miss any flags.  */
  memset (expression, 0, sizeof *expression);

  terminating_char = get_symbol_name (&regname);

  pval = str_hash_find (main_reg_hash, regname);
  if (pval == NULL)
    as_bad (_("Expected register, got '%s'."), regname);

  regno_and_flags = (int)(size_t)pval;
  regno = EXTRACT_REGNO(regno_and_flags);

  if ((regno_and_flags & NONCANONICAL_REG_NAME_FLAG)
      && require_canonical_reg_names)
    as_warn (_("Found use of non-canonical register name %s; "
               "use %s instead."),
             regname, tilegx_register_names[regno]);

  /* Restore the old character following the register name.  */
  (void) restore_line_pointer (terminating_char);

  /* Fill in the expression fields to indicate it's a register.  */
  expression->X_op = O_register;
  expression->X_add_number = regno;
}


/* Parses and type-checks comma-separated operands in input_line_pointer.  */

static void
parse_operands (const char *opcode_name,
                const unsigned char *operands,
                int num_operands,
                expressionS *operand_values)
{
  int i;

  memset (operand_values, 0, num_operands * sizeof operand_values[0]);

  SKIP_WHITESPACE ();
  for (i = 0; i < num_operands; i++)
    {
      tilegx_operand_type type = tilegx_operands[operands[i]].type;

      SKIP_WHITESPACE ();

      if (type == TILEGX_OP_TYPE_REGISTER)
        {
          parse_reg_expression (&operand_values[i]);
        }
      else if (*input_line_pointer == '}')
        {
          operand_values[i].X_op = O_absent;
        }
      else if (type == TILEGX_OP_TYPE_SPR)
        {
          /* Modify the expression parser to add SPRs to the namespace.  */
          parsing_spr = 1;
          expression (&operand_values[i]);
          parsing_spr = 0;
        }
      else
        {
          expression (&operand_values[i]);
        }

      SKIP_WHITESPACE ();

      if (i + 1 < num_operands)
        {
          int separator = (unsigned char)*input_line_pointer++;

          if (is_end_of_line[separator] || (separator == '}'))
            {
              as_bad (_("Too few operands to '%s'."), opcode_name);
              return;
            }
          else if (separator != ',')
            {
              as_bad (_("Unexpected character '%c' after operand %d to %s."),
                      (char)separator, i + 1, opcode_name);
              return;
            }
        }

      /* Arbitrarily use the first valid pipe to get the operand type,
         since they are all the same.  */
      switch (tilegx_operands[operands[i]].type)
        {
        case TILEGX_OP_TYPE_REGISTER:
          /* Handled in parse_reg_expression already.  */
          break;
        case TILEGX_OP_TYPE_SPR:
          /* Fall through  */
        case TILEGX_OP_TYPE_IMMEDIATE:
          /* Fall through  */
        case TILEGX_OP_TYPE_ADDRESS:
          if (   operand_values[i].X_op == O_register
                 || operand_values[i].X_op == O_illegal
                 || operand_values[i].X_op == O_absent)
            as_bad (_("Expected immediate expression"));
          break;
        default:
          abort();
        }
    }

  if (!is_end_of_line[(unsigned char)*input_line_pointer])
    {
      switch (*input_line_pointer)
        {
        case '}':
          if (!inside_bundle)
            as_bad (_("Found '}' when not bundling."));
          ++input_line_pointer;
          inside_bundle = 0;
          demand_empty_rest_of_line ();
          break;

        case ',':
          as_bad (_("Too many operands"));
          break;

        default:
          /* Use default error for unrecognized garbage.  */
          demand_empty_rest_of_line ();
          break;
        }
    }
}


/* This is the guts of the machine-dependent assembler.  STR points to a
   machine dependent instruction.  This function is supposed to emit the
   frags/bytes it assembles to.  */

void
md_assemble (char *str)
{
  char old_char;
  size_t opname_len;
  char *old_input_line_pointer;
  const struct tilegx_opcode *op;
  int first_pipe;

  /* Split off the opcode and look it up.  */
  opname_len = strcspn (str, " {}");
  old_char = str[opname_len];
  str[opname_len] = '\0';

  op = str_hash_find (op_hash, str);
  str[opname_len] = old_char;
  if (op == NULL)
    {
      as_bad (_("Unknown opcode `%.*s'."), (int)opname_len, str);
      return;
    }

  /* Prepare to parse the operands.  */
  old_input_line_pointer = input_line_pointer;
  input_line_pointer = str + opname_len;
  SKIP_WHITESPACE ();

  if (current_bundle_index == TILEGX_MAX_INSTRUCTIONS_PER_BUNDLE)
    {
      as_bad (_("Too many instructions for bundle."));
      tilegx_flush_bundle ();
    }

  /* Make sure we have room for the upcoming bundle before we
     create any fixups. Otherwise if we have to switch to a new
     frag the fixup dot_value fields will be wrong.  */
  frag_grow (TILEGX_BUNDLE_SIZE_IN_BYTES);

  /* Find a valid pipe for this opcode.  */
  for (first_pipe = 0; (op->pipes & (1 << first_pipe)) == 0; first_pipe++)
    ;

  /* Call the function that assembles this instruction.  */
  current_bundle[current_bundle_index].opcode = op;
  parse_operands (op->name,
                  &op->operands[first_pipe][0],
                  op->num_operands,
                  current_bundle[current_bundle_index].operand_values);
  ++current_bundle_index;

  /* Restore the saved value of input_line_pointer.  */
  input_line_pointer = old_input_line_pointer;

  /* If we weren't inside curly braces, go ahead and emit
     this lone instruction as a bundle right now.  */
  if (!inside_bundle)
    tilegx_flush_bundle ();
}


static void
s_require_canonical_reg_names (int require)
{
  demand_empty_rest_of_line ();
  require_canonical_reg_names = require;
}

static void
s_allow_suspicious_bundles (int allow)
{
  demand_empty_rest_of_line ();
  allow_suspicious_bundles = allow;
}

const pseudo_typeS md_pseudo_table[] =
{
  {"align", s_align_bytes, 0},  /* Defaulting is invalid (0).  */
  {"word", cons, 4},
  {"require_canonical_reg_names", s_require_canonical_reg_names, 1 },
  {"no_require_canonical_reg_names", s_require_canonical_reg_names, 0 },
  {"allow_suspicious_bundles", s_allow_suspicious_bundles, 1 },
  {"no_allow_suspicious_bundles", s_allow_suspicious_bundles, 0 },
  { NULL, 0, 0 }
};

void
md_number_to_chars (char * buf, valueT val, int n)
{
  if (target_big_endian)
    number_to_chars_bigendian (buf, val, n);
  else
    number_to_chars_littleendian (buf, val, n);
}

/* Turn the string pointed to by litP into a floating point constant
   of type TYPE, and emit the appropriate bytes.  The number of
   LITTLENUMS emitted is stored in *SIZEP.  An error message is
   returned, or NULL on OK.  */

const char *
md_atof (int type, char *litP, int *sizeP)
{
  int prec;
  LITTLENUM_TYPE words[MAX_LITTLENUMS];
  LITTLENUM_TYPE *wordP;
  char *t;

  switch (type)
    {
    case 'f':
    case 'F':
      prec = 2;
      break;

    case 'd':
    case 'D':
      prec = 4;
      break;

    default:
      *sizeP = 0;
      return _("Bad call to md_atof ()");
    }
  t = atof_ieee (input_line_pointer, type, words);
  if (t)
    input_line_pointer = t;

  *sizeP = prec * sizeof (LITTLENUM_TYPE);
  /* This loops outputs the LITTLENUMs in REVERSE order; in accord with
     the bigendian 386.  */
  for (wordP = words + prec - 1; prec--;)
    {
      md_number_to_chars (litP, (valueT) (*wordP--), sizeof (LITTLENUM_TYPE));
      litP += sizeof (LITTLENUM_TYPE);
    }
  return 0;
}


/* We have no need to default values of symbols.  */

symbolS *
md_undefined_symbol (char *name ATTRIBUTE_UNUSED)
{
  return NULL;
}


void
tilegx_cons_fix_new (fragS *frag,
                     int where,
                     int nbytes,
                     expressionS *exp)
{
  expressionS subexp;
  bfd_reloc_code_real_type reloc = BFD_RELOC_NONE;
  int no_overflow = 0;
  fixS *fixP;

  /* See if it's one of our special functions.  */
  switch (exp->X_op)
    {
    case O_hw0:
      reloc = BFD_RELOC_TILEGX_HW0;
      no_overflow = 1;
      break;
    case O_hw1:
      reloc = BFD_RELOC_TILEGX_HW1;
      no_overflow = 1;
      break;
    case O_hw2:
      reloc = BFD_RELOC_TILEGX_HW2;
      no_overflow = 1;
      break;
    case O_hw3:
      reloc = BFD_RELOC_TILEGX_HW3;
      no_overflow = 1;
      break;
    case O_hw0_last:
      reloc = BFD_RELOC_TILEGX_HW0_LAST;
      break;
    case O_hw1_last:
      reloc = BFD_RELOC_TILEGX_HW1_LAST;
      break;
    case O_hw2_last:
      reloc = BFD_RELOC_TILEGX_HW2_LAST;
      break;

    default:
      /* Do nothing.  */
      break;
    }

  if (reloc != BFD_RELOC_NONE)
    {
      if (nbytes != 2)
        {
          as_bad (_("This operator only produces two byte values."));
          nbytes = 2;
        }

      memset (&subexp, 0, sizeof subexp);
      subexp.X_op = O_symbol;
      subexp.X_add_symbol = exp->X_add_symbol;
      exp = &subexp;
    }
  else
    {
      switch (nbytes)
        {
        case 1:
          reloc = BFD_RELOC_8;
          break;
        case 2:
          reloc = BFD_RELOC_16;
          break;
        case 4:
          reloc = BFD_RELOC_32;
          break;
        case 8:
          reloc = BFD_RELOC_64;
          break;
        default:
          as_bad (_("unsupported BFD relocation size %d"), nbytes);
          reloc = BFD_RELOC_64;
          break;
        }
    }

  fixP = fix_new_exp (frag, where, nbytes, exp, 0, reloc);
  fixP->tc_fix_data = NULL;
  fixP->fx_no_overflow |= no_overflow;
}


void
md_apply_fix (fixS *fixP, valueT * valP, segT seg ATTRIBUTE_UNUSED)
{
  const struct tilegx_operand *operand;
  valueT value = *valP;
  operatorT special;
  char *p;

  /* Leave these for the linker.  */
  if (fixP->fx_r_type == BFD_RELOC_VTABLE_INHERIT
      || fixP->fx_r_type == BFD_RELOC_VTABLE_ENTRY)
    return;

  if (fixP->fx_subsy != (symbolS *) NULL)
    {
      /* We can't actually support subtracting a symbol.  */
      as_bad_subtract (fixP);
    }

  /* Correct relocation types for pc-relativeness.  */
  switch (fixP->fx_r_type)
    {
#define FIX_PCREL(rtype)                        \
      case rtype:                               \
        if (fixP->fx_pcrel)                     \
          fixP->fx_r_type = rtype##_PCREL;      \
      break;                                    \
                                                \
    case rtype##_PCREL:                         \
      if (!fixP->fx_pcrel)                      \
        fixP->fx_r_type = rtype;                \
      break

#define FIX_PLT_PCREL(rtype)                    \
      case rtype##_PLT_PCREL:                   \
        if (!fixP->fx_pcrel)                    \
          fixP->fx_r_type = rtype;              \
                                                \
      break;

      FIX_PCREL (BFD_RELOC_8);
      FIX_PCREL (BFD_RELOC_16);
      FIX_PCREL (BFD_RELOC_32);
      FIX_PCREL (BFD_RELOC_64);
      FIX_PCREL (BFD_RELOC_TILEGX_IMM16_X0_HW0);
      FIX_PCREL (BFD_RELOC_TILEGX_IMM16_X1_HW0);
      FIX_PCREL (BFD_RELOC_TILEGX_IMM16_X0_HW1);
      FIX_PCREL (BFD_RELOC_TILEGX_IMM16_X1_HW1);
      FIX_PCREL (BFD_RELOC_TILEGX_IMM16_X0_HW2);
      FIX_PCREL (BFD_RELOC_TILEGX_IMM16_X1_HW2);
      FIX_PCREL (BFD_RELOC_TILEGX_IMM16_X0_HW3);
      FIX_PCREL (BFD_RELOC_TILEGX_IMM16_X1_HW3);
      FIX_PCREL (BFD_RELOC_TILEGX_IMM16_X0_HW0_LAST);
      FIX_PCREL (BFD_RELOC_TILEGX_IMM16_X1_HW0_LAST);
      FIX_PCREL (BFD_RELOC_TILEGX_IMM16_X0_HW1_LAST);
      FIX_PCREL (BFD_RELOC_TILEGX_IMM16_X1_HW1_LAST);
      FIX_PCREL (BFD_RELOC_TILEGX_IMM16_X0_HW2_LAST);
      FIX_PCREL (BFD_RELOC_TILEGX_IMM16_X1_HW2_LAST);
      FIX_PLT_PCREL (BFD_RELOC_TILEGX_IMM16_X0_HW0);
      FIX_PLT_PCREL (BFD_RELOC_TILEGX_IMM16_X1_HW0);
      FIX_PLT_PCREL (BFD_RELOC_TILEGX_IMM16_X0_HW1);
      FIX_PLT_PCREL (BFD_RELOC_TILEGX_IMM16_X1_HW1);
      FIX_PLT_PCREL (BFD_RELOC_TILEGX_IMM16_X0_HW1_LAST);
      FIX_PLT_PCREL (BFD_RELOC_TILEGX_IMM16_X1_HW1_LAST);
      FIX_PLT_PCREL (BFD_RELOC_TILEGX_IMM16_X0_HW2_LAST);
      FIX_PLT_PCREL (BFD_RELOC_TILEGX_IMM16_X1_HW2_LAST);

#undef FIX_PCREL

    default:
      /* Do nothing  */
      break;
    }

  if (fixP->fx_addsy != NULL)
    {
#ifdef OBJ_ELF
      switch (fixP->fx_r_type)
        {
        case BFD_RELOC_TILEGX_IMM8_X0_TLS_ADD:
        case BFD_RELOC_TILEGX_IMM8_X1_TLS_ADD:
        case BFD_RELOC_TILEGX_IMM8_Y0_TLS_ADD:
        case BFD_RELOC_TILEGX_IMM8_Y1_TLS_ADD:
        case BFD_RELOC_TILEGX_IMM8_X0_TLS_GD_ADD:
        case BFD_RELOC_TILEGX_IMM8_X1_TLS_GD_ADD:
        case BFD_RELOC_TILEGX_IMM8_Y0_TLS_GD_ADD:
        case BFD_RELOC_TILEGX_IMM8_Y1_TLS_GD_ADD:
        case BFD_RELOC_TILEGX_IMM16_X0_HW0_TLS_GD:
        case BFD_RELOC_TILEGX_IMM16_X1_HW0_TLS_GD:
        case BFD_RELOC_TILEGX_IMM16_X0_HW0_LAST_TLS_GD:
        case BFD_RELOC_TILEGX_IMM16_X1_HW0_LAST_TLS_GD:
        case BFD_RELOC_TILEGX_IMM16_X0_HW1_LAST_TLS_GD:
        case BFD_RELOC_TILEGX_IMM16_X1_HW1_LAST_TLS_GD:
        case BFD_RELOC_TILEGX_IMM16_X0_HW0_TLS_IE:
        case BFD_RELOC_TILEGX_IMM16_X1_HW0_TLS_IE:
        case BFD_RELOC_TILEGX_IMM16_X0_HW0_LAST_TLS_IE:
        case BFD_RELOC_TILEGX_IMM16_X1_HW0_LAST_TLS_IE:
        case BFD_RELOC_TILEGX_IMM16_X0_HW1_LAST_TLS_IE:
        case BFD_RELOC_TILEGX_IMM16_X1_HW1_LAST_TLS_IE:
        case BFD_RELOC_TILEGX_IMM16_X0_HW0_TLS_LE:
        case BFD_RELOC_TILEGX_IMM16_X1_HW0_TLS_LE:
        case BFD_RELOC_TILEGX_IMM16_X0_HW0_LAST_TLS_LE:
        case BFD_RELOC_TILEGX_IMM16_X1_HW0_LAST_TLS_LE:
        case BFD_RELOC_TILEGX_IMM16_X0_HW1_LAST_TLS_LE:
        case BFD_RELOC_TILEGX_IMM16_X1_HW1_LAST_TLS_LE:
        case BFD_RELOC_TILEGX_TLS_GD_CALL:
        case BFD_RELOC_TILEGX_TLS_IE_LOAD:
        case BFD_RELOC_TILEGX_TLS_DTPMOD64:
        case BFD_RELOC_TILEGX_TLS_DTPOFF64:
        case BFD_RELOC_TILEGX_TLS_TPOFF64:
        case BFD_RELOC_TILEGX_TLS_DTPMOD32:
        case BFD_RELOC_TILEGX_TLS_DTPOFF32:
        case BFD_RELOC_TILEGX_TLS_TPOFF32:
          S_SET_THREAD_LOCAL (fixP->fx_addsy);
          break;

        default:
          /* Do nothing  */
          break;
        }
#endif
      return;
    }

  /* Apply hw0, etc.  */
  special = O_illegal;
  switch (fixP->fx_r_type)
    {
    case BFD_RELOC_TILEGX_HW0:
    case BFD_RELOC_TILEGX_IMM16_X0_HW0:
    case BFD_RELOC_TILEGX_IMM16_X1_HW0:
    case BFD_RELOC_TILEGX_IMM16_X0_HW0_PCREL:
    case BFD_RELOC_TILEGX_IMM16_X1_HW0_PCREL:
    case BFD_RELOC_TILEGX_IMM16_X0_HW0_PLT_PCREL:
    case BFD_RELOC_TILEGX_IMM16_X1_HW0_PLT_PCREL:
      special = O_hw0;
      break;

    case BFD_RELOC_TILEGX_HW0_LAST:
    case BFD_RELOC_TILEGX_IMM16_X0_HW0_LAST:
    case BFD_RELOC_TILEGX_IMM16_X1_HW0_LAST:
    case BFD_RELOC_TILEGX_IMM16_X0_HW0_LAST_PCREL:
    case BFD_RELOC_TILEGX_IMM16_X1_HW0_LAST_PCREL:
    case BFD_RELOC_TILEGX_IMM16_X0_HW0_LAST_PLT_PCREL:
    case BFD_RELOC_TILEGX_IMM16_X1_HW0_LAST_PLT_PCREL:
      special = O_hw0_last;
      break;

    case BFD_RELOC_TILEGX_HW1:
    case BFD_RELOC_TILEGX_IMM16_X0_HW1:
    case BFD_RELOC_TILEGX_IMM16_X1_HW1:
    case BFD_RELOC_TILEGX_IMM16_X0_HW1_PCREL:
    case BFD_RELOC_TILEGX_IMM16_X1_HW1_PCREL:
    case BFD_RELOC_TILEGX_IMM16_X0_HW1_PLT_PCREL:
    case BFD_RELOC_TILEGX_IMM16_X1_HW1_PLT_PCREL:
      special = O_hw1;
      break;

    case BFD_RELOC_TILEGX_HW1_LAST:
    case BFD_RELOC_TILEGX_IMM16_X0_HW1_LAST:
    case BFD_RELOC_TILEGX_IMM16_X1_HW1_LAST:
    case BFD_RELOC_TILEGX_IMM16_X0_HW1_LAST_PCREL:
    case BFD_RELOC_TILEGX_IMM16_X1_HW1_LAST_PCREL:
    case BFD_RELOC_TILEGX_IMM16_X0_HW1_LAST_PLT_PCREL:
    case BFD_RELOC_TILEGX_IMM16_X1_HW1_LAST_PLT_PCREL:
      special = O_hw1_last;
      break;

    case BFD_RELOC_TILEGX_HW2:
    case BFD_RELOC_TILEGX_IMM16_X0_HW2:
    case BFD_RELOC_TILEGX_IMM16_X1_HW2:
    case BFD_RELOC_TILEGX_IMM16_X0_HW2_PCREL:
    case BFD_RELOC_TILEGX_IMM16_X1_HW2_PCREL:
    case BFD_RELOC_TILEGX_IMM16_X0_HW2_PLT_PCREL:
    case BFD_RELOC_TILEGX_IMM16_X1_HW2_PLT_PCREL:
      special = O_hw2;
      break;

    case BFD_RELOC_TILEGX_HW2_LAST:
    case BFD_RELOC_TILEGX_IMM16_X0_HW2_LAST:
    case BFD_RELOC_TILEGX_IMM16_X1_HW2_LAST:
    case BFD_RELOC_TILEGX_IMM16_X0_HW2_LAST_PCREL:
    case BFD_RELOC_TILEGX_IMM16_X1_HW2_LAST_PCREL:
    case BFD_RELOC_TILEGX_IMM16_X0_HW2_LAST_PLT_PCREL:
    case BFD_RELOC_TILEGX_IMM16_X1_HW2_LAST_PLT_PCREL:
      special = O_hw2_last;
      break;

    case BFD_RELOC_TILEGX_HW3:
    case BFD_RELOC_TILEGX_IMM16_X0_HW3:
    case BFD_RELOC_TILEGX_IMM16_X1_HW3:
    case BFD_RELOC_TILEGX_IMM16_X0_HW3_PCREL:
    case BFD_RELOC_TILEGX_IMM16_X1_HW3_PCREL:
    case BFD_RELOC_TILEGX_IMM16_X0_HW3_PLT_PCREL:
    case BFD_RELOC_TILEGX_IMM16_X1_HW3_PLT_PCREL:
      special = O_hw3;
      break;

    default:
      /* Do nothing  */
      break;
    }

  if (special != O_illegal)
    {
      *valP = value = apply_special_operator (special, value,
                                              fixP->fx_file, fixP->fx_line);
    }

  p = fixP->fx_frag->fr_literal + fixP->fx_where;

  operand = fixP->tc_fix_data;
  if (operand != NULL)
    {
      /* It's an instruction operand.  */
      tilegx_bundle_bits bits =
        insert_operand (0, operand, value, fixP->fx_file, fixP->fx_line);

      /* Note that we might either be writing out bits for a bundle
         or a static network instruction, which are different sizes, so it's
         important to stop touching memory once we run out of bits.
         ORing in values is OK since we know the existing bits for
         this operand are zero.  */
      for (; bits != 0; bits >>= 8)
        *p++ |= (char)bits;
    }
  else
    {
      /* Some other kind of relocation.  */
      switch (fixP->fx_r_type)
        {
        case BFD_RELOC_8:
        case BFD_RELOC_8_PCREL:
          md_number_to_chars (p, value, 1);
          break;

        case BFD_RELOC_16:
        case BFD_RELOC_16_PCREL:
          md_number_to_chars (p, value, 2);
          break;

        case BFD_RELOC_32:
        case BFD_RELOC_32_PCREL:
          md_number_to_chars (p, value, 4);
          break;

        case BFD_RELOC_64:
        case BFD_RELOC_64_PCREL:
          md_number_to_chars (p, value, 8);
          break;

        default:
          /* Leave it for the linker.  */
          return;
        }
    }

  fixP->fx_done = 1;
}


/* Generate the BFD reloc to be stuck in the object file from the
   fixup used internally in the assembler.  */

arelent *
tc_gen_reloc (asection *sec ATTRIBUTE_UNUSED, fixS *fixp)
{
  arelent *reloc;

  reloc = XNEW (arelent);
  reloc->sym_ptr_ptr = XNEW (asymbol *);
  *reloc->sym_ptr_ptr = symbol_get_bfdsym (fixp->fx_addsy);
  reloc->address = fixp->fx_frag->fr_address + fixp->fx_where;

  /* Make sure none of our internal relocations make it this far.
     They'd better have been fully resolved by this point.  */
  gas_assert ((int) fixp->fx_r_type > 0);

  reloc->howto = bfd_reloc_type_lookup (stdoutput, fixp->fx_r_type);
  if (reloc->howto == NULL)
    {
      as_bad_where (fixp->fx_file, fixp->fx_line,
                    _("cannot represent `%s' relocation in object file"),
                    bfd_get_reloc_code_name (fixp->fx_r_type));
      return NULL;
    }

  if (!fixp->fx_pcrel != !reloc->howto->pc_relative)
    {
      as_fatal (_("internal error? cannot generate `%s' relocation (%d, %d)"),
                bfd_get_reloc_code_name (fixp->fx_r_type),
                fixp->fx_pcrel, reloc->howto->pc_relative);
    }
  gas_assert (!fixp->fx_pcrel == !reloc->howto->pc_relative);

  reloc->addend = fixp->fx_offset;

  return reloc;
}


/* The location from which a PC relative jump should be calculated,
   given a PC relative reloc.  */

long
md_pcrel_from (fixS *fixP)
{
  return fixP->fx_frag->fr_address + fixP->fx_where;
}


/* Return 1 if it's OK to adjust a reloc by replacing the symbol with
   a section symbol plus some offset.  */
int
tilegx_fix_adjustable (fixS *fix)
{
  /* Prevent all adjustments to global symbols  */
  if (S_IS_EXTERNAL (fix->fx_addsy) || S_IS_WEAK (fix->fx_addsy))
    return 0;

  return 1;
}


int
tilegx_unrecognized_line (int ch)
{
  switch (ch)
    {
    case '{':
      if (inside_bundle)
        {
          as_bad (_("Found '{' when already bundling."));
        }
      else
        {
          inside_bundle = 1;
          current_bundle_index = 0;
        }
      return 1;

    case '}':
      if (!inside_bundle)
        {
          as_bad (_("Found '}' when not bundling."));
        }
      else
        {
          tilegx_flush_bundle ();
        }

      /* Allow '{' to follow on the same line.  We also allow ";;", but that
         happens automatically because ';' is an end of line marker.  */
      SKIP_WHITESPACE ();
      if (input_line_pointer[0] == '{')
        {
          input_line_pointer++;
          return tilegx_unrecognized_line ('{');
        }

      demand_empty_rest_of_line ();
      return 1;

    default:
      break;
    }

  /* Not a valid line.  */
  return 0;
}


/* This is called from HANDLE_ALIGN in write.c.  Fill in the contents
   of an rs_align_code fragment.  */

void
tilegx_handle_align (fragS *fragp)
{
  addressT bytes, fix;
  char *p;

  if (fragp->fr_type != rs_align_code)
    return;

  bytes = fragp->fr_next->fr_address - fragp->fr_address - fragp->fr_fix;
  p = fragp->fr_literal + fragp->fr_fix;
  fix = 0;

  /* Determine the bits for NOP.  */
  const struct tilegx_opcode *nop_opcode =
    &tilegx_opcodes[TILEGX_OPC_NOP];
  tilegx_bundle_bits nop =
    (  nop_opcode->fixed_bit_values[TILEGX_PIPELINE_X0]
     | nop_opcode->fixed_bit_values[TILEGX_PIPELINE_X1]);

  if ((bytes & (TILEGX_BUNDLE_SIZE_IN_BYTES - 1)) != 0)
    {
      fix = bytes & (TILEGX_BUNDLE_SIZE_IN_BYTES - 1);
      memset (p, 0, fix);
      p += fix;
      bytes -= fix;
    }

  number_to_chars_littleendian (p, nop, 8);
  fragp->fr_fix += fix;
  fragp->fr_var = TILEGX_BUNDLE_SIZE_IN_BYTES;
}

/* Standard calling conventions leave the CFA at SP on entry.  */
void
tilegx_cfi_frame_initial_instructions (void)
{
  cfi_add_CFA_def_cfa_register (54);
}

int
tc_tilegx_regname_to_dw2regnum (char *regname)
{
  int i;
  for (i = 0; i < TILEGX_NUM_REGISTERS; i++)
    {
      if (!strcmp (regname, tilegx_register_names[i]))
        return i;
    }

  return -1;
}