2002-10-02 Nathanael Nerode <neroden@gcc.gnu.org>

[binutils.git] / gas / config / tc-h8300.c

/* tc-h8300.c -- Assemble code for the Hitachi H8/300
   Copyright 1991, 1992, 1993, 1994, 1995, 1996, 1997, 1998, 2000,
   2001, 2002 Free Software Foundation, Inc.

   This file is part of GAS, the GNU Assembler.

   GAS 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 2, or (at your option)
   any later version.

   GAS 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 GAS; see the file COPYING.  If not, write to the Free
   Software Foundation, 59 Temple Place - Suite 330, Boston, MA
   02111-1307, USA.  */

/* Written By Steve Chamberlain <sac@cygnus.com>.  */

#include <stdio.h>
#include "as.h"
#include "subsegs.h"
#include "bfd.h"
#define DEFINE_TABLE
#define h8_opcodes ops
#include "opcode/h8300.h"
#include "safe-ctype.h"

#ifdef OBJ_ELF
#include "elf/h8.h"
#endif

const char comment_chars[] = ";";
const char line_comment_chars[] = "#";
const char line_separator_chars[] = "";

void cons        PARAMS ((int));
void sbranch     PARAMS ((int));
void h8300hmode  PARAMS ((int));
void h8300smode  PARAMS ((int));
static void pint PARAMS ((int));

int Hmode;
int Smode;

#define PSIZE (Hmode ? L_32 : L_16)
#define DMODE (L_16)
#define DSYMMODE (Hmode ? L_24 : L_16)

int bsize = L_8;                /* default branch displacement */

void
h8300hmode (arg)
     int arg ATTRIBUTE_UNUSED;
{
  Hmode = 1;
  Smode = 0;
#ifdef BFD_ASSEMBLER
  if (!bfd_set_arch_mach (stdoutput, bfd_arch_h8300, bfd_mach_h8300h))
    as_warn (_("could not set architecture and machine"));
#endif
}

void
h8300smode (arg)
     int arg ATTRIBUTE_UNUSED;
{
  Smode = 1;
  Hmode = 1;
#ifdef BFD_ASSEMBLER
  if (!bfd_set_arch_mach (stdoutput, bfd_arch_h8300, bfd_mach_h8300s))
    as_warn (_("could not set architecture and machine"));
#endif
}

void
sbranch (size)
     int size;
{
  bsize = size;
}

static void
pint (arg)
     int arg ATTRIBUTE_UNUSED;
{
  cons (Hmode ? 4 : 2);
}

/* This table describes all the machine specific pseudo-ops the assembler
   has to support.  The fields are:
   pseudo-op name without dot
   function to call to execute this pseudo-op
   Integer arg to pass to the function.  */

const pseudo_typeS md_pseudo_table[] =
{
  {"h8300h", h8300hmode, 0},
  {"h8300s", h8300smode, 0},
  {"sbranch", sbranch, L_8},
  {"lbranch", sbranch, L_16},

  {"int", pint, 0},
  {"data.b", cons, 1},
  {"data.w", cons, 2},
  {"data.l", cons, 4},
  {"form", listing_psize, 0},
  {"heading", listing_title, 0},
  {"import", s_ignore, 0},
  {"page", listing_eject, 0},
  {"program", s_ignore, 0},
  {0, 0, 0}
};

const int md_reloc_size;

const char EXP_CHARS[] = "eE";

/* Chars that mean this number is a floating point constant
   As in 0f12.456
   or    0d1.2345e12.  */
const char FLT_CHARS[] = "rRsSfFdDxXpP";

static struct hash_control *opcode_hash_control;        /* Opcode mnemonics.  */

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

void
md_begin ()
{
  struct h8_opcode *opcode;
  char prev_buffer[100];
  int idx = 0;

#ifdef BFD_ASSEMBLER
  if (!bfd_set_arch_mach (stdoutput, bfd_arch_h8300, bfd_mach_h8300))
    as_warn (_("could not set architecture and machine"));
#endif

  opcode_hash_control = hash_new ();
  prev_buffer[0] = 0;

  for (opcode = h8_opcodes; opcode->name; opcode++)
    {
      /* Strip off any . part when inserting the opcode and only enter
         unique codes into the hash table.  */
      char *src = opcode->name;
      unsigned int len = strlen (src);
      char *dst = malloc (len + 1);
      char *buffer = dst;

      opcode->size = 0;
      while (*src)
        {
          if (*src == '.')
            {
              src++;
              opcode->size = *src;
              break;
            }
          *dst++ = *src++;
        }
      *dst++ = 0;
      if (strcmp (buffer, prev_buffer))
        {
          hash_insert (opcode_hash_control, buffer, (char *) opcode);
          strcpy (prev_buffer, buffer);
          idx++;
        }
      opcode->idx = idx;

      /* Find the number of operands.  */
      opcode->noperands = 0;
      while (opcode->args.nib[opcode->noperands] != E)
        opcode->noperands++;

      /* Find the length of the opcode in bytes.  */
      opcode->length = 0;
      while (opcode->data.nib[opcode->length * 2] != E)
        opcode->length++;
    }

  linkrelax = 1;
}

struct h8_exp
{
  char *e_beg;
  char *e_end;
  expressionS e_exp;
};

int dispreg;
int opsize;                     /* Set when a register size is seen.  */

struct h8_op
{
  op_type mode;
  unsigned reg;
  expressionS exp;
};

static void clever_message PARAMS ((struct h8_opcode *, struct h8_op *));
static void build_bytes    PARAMS ((struct h8_opcode *, struct h8_op *));
static void do_a_fix_imm   PARAMS ((int, struct h8_op *, int));
static void check_operand  PARAMS ((struct h8_op *, unsigned int, char *));
static struct h8_opcode * get_specific PARAMS ((struct h8_opcode *, struct h8_op *, int));
static char * get_operands PARAMS ((unsigned, char *, struct h8_op *));
static void   get_operand  PARAMS ((char **, struct h8_op *, unsigned, int));
static char * skip_colonthing PARAMS ((char *, expressionS *, int *));
static char * parse_exp PARAMS ((char *, expressionS *));
static int    parse_reg PARAMS ((char *, op_type *, unsigned *, int));
char * colonmod24 PARAMS ((struct h8_op *, char *));

/*
  parse operands
  WREG r0,r1,r2,r3,r4,r5,r6,r7,fp,sp
  r0l,r0h,..r7l,r7h
  @WREG
  @WREG+
  @-WREG
  #const
  ccr
*/

/* Try to parse a reg name.  Return the number of chars consumed.  */

static int
parse_reg (src, mode, reg, direction)
     char *src;
     op_type *mode;
     unsigned int *reg;
     int direction;
{
  char *end;
  int len;

  /* Cribbed from get_symbol_end.  */
  if (!is_name_beginner (*src) || *src == '\001')
    return 0;
  end = src + 1;
  while (is_part_of_name (*end) || *end == '\001')
    end++;
  len = end - src;

  if (len == 2 && src[0] == 's' && src[1] == 'p')
    {
      *mode = PSIZE | REG | direction;
      *reg = 7;
      return len;
    }
  if (len == 3 && src[0] == 'c' && src[1] == 'c' && src[2] == 'r')
    {
      *mode = CCR;
      *reg = 0;
      return len;
    }
  if (len == 3 && src[0] == 'e' && src[1] == 'x' && src[2] == 'r')
    {
      *mode = EXR;
      *reg = 0;
      return len;
    }
  if (len == 2 && src[0] == 'f' && src[1] == 'p')
    {
      *mode = PSIZE | REG | direction;
      *reg = 6;
      return len;
    }
  if (len == 3 && src[0] == 'e' && src[1] == 'r'
      && src[2] >= '0' && src[2] <= '7')
    {
      *mode = L_32 | REG | direction;
      *reg = src[2] - '0';
      if (!Hmode)
        as_warn (_("Reg not valid for H8/300"));
      return len;
    }
  if (len == 2 && src[0] == 'e' && src[1] >= '0' && src[1] <= '7')
    {
      *mode = L_16 | REG | direction;
      *reg = src[1] - '0' + 8;
      if (!Hmode)
        as_warn (_("Reg not valid for H8/300"));
      return len;
    }

  if (src[0] == 'r')
    {
      if (src[1] >= '0' && src[1] <= '7')
        {
          if (len == 3 && src[2] == 'l')
            {
              *mode = L_8 | REG | direction;
              *reg = (src[1] - '0') + 8;
              return len;
            }
          if (len == 3 && src[2] == 'h')
            {
              *mode = L_8 | REG | direction;
              *reg = (src[1] - '0');
              return len;
            }
          if (len == 2)
            {
              *mode = L_16 | REG | direction;
              *reg = (src[1] - '0');
              return len;
            }
        }
    }

  return 0;
}

static char *
parse_exp (s, op)
     char *s;
     expressionS *op;
{
  char *save = input_line_pointer;
  char *new;

  input_line_pointer = s;
  expression (op);
  if (op->X_op == O_absent)
    as_bad (_("missing operand"));
  new = input_line_pointer;
  input_line_pointer = save;
  return new;
}

static char *
skip_colonthing (ptr, exp, mode)
     char *ptr;
     expressionS *exp ATTRIBUTE_UNUSED;
     int *mode;
{
  if (*ptr == ':')
    {
      ptr++;
      *mode &= ~SIZE;
      if (*ptr == '8')
        {
          ptr++;
          /* ff fill any 8 bit quantity.  */
          /* exp->X_add_number -= 0x100; */
          *mode |= L_8;
        }
      else
        {
          if (*ptr == '2')
            {
              *mode |= L_24;
            }
          else if (*ptr == '3')
            {
              *mode |= L_32;
            }
          else if (*ptr == '1')
            {
              *mode |= L_16;
            }
          while (ISDIGIT (*ptr))
            ptr++;
        }
    }
  return ptr;
}

/* The many forms of operand:

   Rn                   Register direct
   @Rn                  Register indirect
   @(exp[:16], Rn)      Register indirect with displacement
   @Rn+
   @-Rn
   @aa:8                absolute 8 bit
   @aa:16               absolute 16 bit
   @aa                  absolute 16 bit

   #xx[:size]           immediate data
   @(exp:[8], pc)       pc rel
   @@aa[:8]             memory indirect.  */

char *
colonmod24 (op, src)
     struct h8_op *op;
     char *src;
{
  int mode = 0;
  src = skip_colonthing (src, &op->exp, &mode);

  if (!mode)
    {
      /* Choose a default mode.  */
      if (op->exp.X_add_number < -32768
          || op->exp.X_add_number > 32767)
        {
          if (Hmode)
            mode = L_24;
          else
            mode = L_16;
        }
      else if (op->exp.X_add_symbol
               || op->exp.X_op_symbol)
        mode = DSYMMODE;
      else
        mode = DMODE;
    }

  op->mode |= mode;
  return src;
}

static void
get_operand (ptr, op, dst, direction)
     char **ptr;
     struct h8_op *op;
     unsigned int dst ATTRIBUTE_UNUSED;
     int direction;
{
  char *src = *ptr;
  op_type mode;
  unsigned int num;
  unsigned int len;

  op->mode = E;

  /* Check for '(' and ')' for instructions ldm and stm.  */
  if (src[0] == '(' && src[8] == ')')
    ++ src;

  /* Gross.  Gross.  ldm and stm have a format not easily handled
     by get_operand.  We deal with it explicitly here.  */
  if (src[0] == 'e' && src[1] == 'r' && ISDIGIT (src[2])
      && src[3] == '-' && src[4] == 'e' && src[5] == 'r' && ISDIGIT (src[6]))
    {
      int low, high;

      low = src[2] - '0';
      high = src[6] - '0';

      if (high < low)
        as_bad (_("Invalid register list for ldm/stm\n"));

      if (low % 2)
        as_bad (_("Invalid register list for ldm/stm\n"));

      if (high - low > 3)
        as_bad (_("Invalid register list for ldm/stm\n"));

      if (high - low != 1
          && low % 4)
        as_bad (_("Invalid register list for ldm/stm\n"));

      /* Even sicker.  We encode two registers into op->reg.  One
         for the low register to save, the other for the high
         register to save;  we also set the high bit in op->reg
         so we know this is "very special".  */
      op->reg = 0x80000000 | (high << 8) | low;
      op->mode = REG;
      if (src[7] == ')')
        *ptr = src + 8;
      else
        *ptr = src + 7;
      return;
    }

  len = parse_reg (src, &op->mode, &op->reg, direction);
  if (len)
    {
      *ptr = src + len;
      return;
    }

  if (*src == '@')
    {
      src++;
      if (*src == '@')
        {
          src++;
          src = parse_exp (src, &op->exp);

          src = skip_colonthing (src, &op->exp, &op->mode);

          *ptr = src;

          op->mode = MEMIND;
          return;
        }

      if (*src == '-')
        {
          src++;
          len = parse_reg (src, &mode, &num, direction);
          if (len == 0)
            {
              /* Oops, not a reg after all, must be ordinary exp.  */
              src--;
              /* Must be a symbol.  */
              op->mode = ABS | PSIZE | direction;
              *ptr = skip_colonthing (parse_exp (src, &op->exp),
                                      &op->exp, &op->mode);

              return;
            }

          if ((mode & SIZE) != PSIZE)
            as_bad (_("Wrong size pointer register for architecture."));
          op->mode = RDDEC;
          op->reg = num;
          *ptr = src + len;
          return;
        }
      if (*src == '(')
        {
          /* Disp.  */
          src++;

          /* Start off assuming a 16 bit offset.  */

          src = parse_exp (src, &op->exp);

          src = colonmod24 (op, src);

          if (*src == ')')
            {
              src++;
              op->mode |= ABS | direction;
              *ptr = src;
              return;
            }

          if (*src != ',')
            {
              as_bad (_("expected @(exp, reg16)"));
              return;

            }
          src++;

          len = parse_reg (src, &mode, &op->reg, direction);
          if (len == 0 || !(mode & REG))
            {
              as_bad (_("expected @(exp, reg16)"));
              return;
            }
          op->mode |= DISP | direction;
          dispreg = op->reg;
          src += len;
          src = skip_colonthing (src, &op->exp, &op->mode);

          if (*src != ')' && '(')
            {
              as_bad (_("expected @(exp, reg16)"));
              return;
            }
          *ptr = src + 1;

          return;
        }
      len = parse_reg (src, &mode, &num, direction);

      if (len)
        {
          src += len;
          if (*src == '+')
            {
              src++;
              if ((mode & SIZE) != PSIZE)
                as_bad (_("Wrong size pointer register for architecture."));
              op->mode = RSINC;
              op->reg = num;
              *ptr = src;
              return;
            }
          if ((mode & SIZE) != PSIZE)
            as_bad (_("Wrong size pointer register for architecture."));

          op->mode = direction | IND | PSIZE;
          op->reg = num;
          *ptr = src;

          return;
        }
      else
        {
          /* must be a symbol */

          op->mode = ABS | direction;
          src = parse_exp (src, &op->exp);

          *ptr = colonmod24 (op, src);

          return;
        }
    }

  if (*src == '#')
    {
      src++;
      op->mode = IMM;
      src = parse_exp (src, &op->exp);
      *ptr = skip_colonthing (src, &op->exp, &op->mode);

      return;
    }
  else if (strncmp (src, "mach", 4) == 0
           || strncmp (src, "macl", 4) == 0)
    {
      op->reg = src[3] == 'l';
      op->mode = MACREG;
      *ptr = src + 4;
      return;
    }
  else
    {
      src = parse_exp (src, &op->exp);
      /* Trailing ':' size ? */
      if (*src == ':')
        {
          if (src[1] == '1' && src[2] == '6')
            {
              op->mode = PCREL | L_16;
              src += 3;
            }
          else if (src[1] == '8')
            {
              op->mode = PCREL | L_8;
              src += 2;
            }
          else
            as_bad (_("expect :8 or :16 here"));
        }
      else
        op->mode = PCREL | bsize;

      *ptr = src;
    }
}

static char *
get_operands (noperands, op_end, operand)
     unsigned int noperands;
     char *op_end;
     struct h8_op *operand;
{
  char *ptr = op_end;

  switch (noperands)
    {
    case 0:
      operand[0].mode = 0;
      operand[1].mode = 0;
      break;

    case 1:
      ptr++;
      get_operand (&ptr, operand + 0, 0, SRC);
      if (*ptr == ',')
        {
          ptr++;
          get_operand (&ptr, operand + 1, 1, DST);
        }
      else
        {
          operand[1].mode = 0;
        }
      break;

    case 2:
      ptr++;
      get_operand (&ptr, operand + 0, 0, SRC);
      if (*ptr == ',')
        ptr++;
      get_operand (&ptr, operand + 1, 1, DST);
      break;

    default:
      abort ();
    }

  return ptr;
}

/* Passed a pointer to a list of opcodes which use different
   addressing modes, return the opcode which matches the opcodes
   provided.  */

static struct h8_opcode *
get_specific (opcode, operands, size)
     struct h8_opcode *opcode;
     struct h8_op *operands;
     int size;
{
  struct h8_opcode *this_try = opcode;
  int found = 0;
  int this_index = opcode->idx;

  /* There's only one ldm/stm and it's easier to just
     get out quick for them.  */
  if (strcmp (opcode->name, "stm.l") == 0
      || strcmp (opcode->name, "ldm.l") == 0)
    return this_try;

  while (this_index == opcode->idx && !found)
    {
      found = 1;

      this_try = opcode++;
      if (this_try->noperands == 0)
        {
          int this_size;

          this_size = this_try->how & SN;
          if (this_size != size && (this_size != SB || size != SN))
            found = 0;
        }
      else
        {
          int i;

          for (i = 0; i < this_try->noperands && found; i++)
            {
              op_type op = this_try->args.nib[i];
              int x = operands[i].mode;

              if ((op & (DISP | REG)) == (DISP | REG)
                  && ((x & (DISP | REG)) == (DISP | REG)))
                {
                  dispreg = operands[i].reg;
                }
              else if (op & REG)
                {
                  if (!(x & REG))
                    found = 0;

                  if (x & L_P)
                    x = (x & ~L_P) | (Hmode ? L_32 : L_16);
                  if (op & L_P)
                    op = (op & ~L_P) | (Hmode ? L_32 : L_16);

                  opsize = op & SIZE;

                  /* The size of the reg is v important.  */
                  if ((op & SIZE) != (x & SIZE))
                    found = 0;
                }
              else if ((op & ABSJMP) && (x & ABS))
                {
                  operands[i].mode &= ~ABS;
                  operands[i].mode |= ABSJMP;
                  /* But it may not be 24 bits long.  */
                  if (!Hmode)
                    {
                      operands[i].mode &= ~SIZE;
                      operands[i].mode |= L_16;
                    }
                }
              else if ((op & (KBIT | DBIT)) && (x & IMM))
                {
                  /* This is ok if the immediate value is sensible.  */
                }
              else if (op & PCREL)
                {
                  /* The size of the displacement is important.  */
                  if ((op & SIZE) != (x & SIZE))
                    found = 0;
                }
              else if ((op & (DISP | IMM | ABS))
                       && (op & (DISP | IMM | ABS)) == (x & (DISP | IMM | ABS)))
                {
                  /* Promote a L_24 to L_32 if it makes us match.  */
                  if ((x & L_24) && (op & L_32))
                    {
                      x &= ~L_24;
                      x |= L_32;
                    }
                  /* Promote an L8 to L_16 if it makes us match.  */
                  if (op & ABS && op & L_8 && op & DISP)
                    {
                      if (x & L_16)
                        found = 1;
                    }
                  else if ((x & SIZE) != 0
                           && ((op & SIZE) != (x & SIZE)))
                    found = 0;
                }
              else if ((op & MACREG) != (x & MACREG))
                {
                  found = 0;
                }
              else if ((op & MODE) != (x & MODE))
                {
                  found = 0;
                }
            }
        }
    }
  if (found)
    return this_try;
  else
    return 0;
}

static void
check_operand (operand, width, string)
     struct h8_op *operand;
     unsigned int width;
     char *string;
{
  if (operand->exp.X_add_symbol == 0
      && operand->exp.X_op_symbol == 0)
    {
      /* No symbol involved, let's look at offset, it's dangerous if
         any of the high bits are not 0 or ff's, find out by oring or
         anding with the width and seeing if the answer is 0 or all
         fs.  */

      if ((operand->exp.X_add_number & ~width) != 0 &&
          (operand->exp.X_add_number | width) != (unsigned)(~0))
        {
          if (width == 255
              && (operand->exp.X_add_number & 0xff00) == 0xff00)
            {
              /* Just ignore this one - which happens when trying to
                 fit a 16 bit address truncated into an 8 bit address
                 of something like bset.  */
            }
          else if (strcmp (string, "@") == 0
                   && width == 0xffff
                   && (operand->exp.X_add_number & 0xff8000) == 0xff8000)
            {
              /* Just ignore this one - which happens when trying to
                 fit a 24 bit address truncated into a 16 bit address
                 of something like mov.w.  */
            }
          else
            {
              as_warn (_("operand %s0x%lx out of range."), string,
                       (unsigned long) operand->exp.X_add_number);
            }
        }
    }
}

/* RELAXMODE has one of 3 values:

   0 Output a "normal" reloc, no relaxing possible for this insn/reloc

   1 Output a relaxable 24bit absolute mov.w address relocation
     (may relax into a 16bit absolute address).

   2 Output a relaxable 16/24 absolute mov.b address relocation
     (may relax into an 8bit absolute address).  */

static void
do_a_fix_imm (offset, operand, relaxmode)
     int offset;
     struct h8_op *operand;
     int relaxmode;
{
  int idx;
  int size;
  int where;

  char *t = operand->mode & IMM ? "#" : "@";

  if (operand->exp.X_add_symbol == 0)
    {
      char *bytes = frag_now->fr_literal + offset;
      switch (operand->mode & SIZE)
        {
        case L_2:
          check_operand (operand, 0x3, t);
          bytes[0] |= (operand->exp.X_add_number) << 4;
          break;
        case L_3:
          check_operand (operand, 0x7, t);
          bytes[0] |= (operand->exp.X_add_number) << 4;
          break;
        case L_8:
          check_operand (operand, 0xff, t);
          bytes[0] = operand->exp.X_add_number;
          break;
        case L_16:
          check_operand (operand, 0xffff, t);
          bytes[0] = operand->exp.X_add_number >> 8;
          bytes[1] = operand->exp.X_add_number >> 0;
          break;
        case L_24:
          check_operand (operand, 0xffffff, t);
          bytes[0] = operand->exp.X_add_number >> 16;
          bytes[1] = operand->exp.X_add_number >> 8;
          bytes[2] = operand->exp.X_add_number >> 0;
          break;

        case L_32:
          /* This should be done with bfd.  */
          bytes[0] = operand->exp.X_add_number >> 24;
          bytes[1] = operand->exp.X_add_number >> 16;
          bytes[2] = operand->exp.X_add_number >> 8;
          bytes[3] = operand->exp.X_add_number >> 0;
          if (relaxmode != 0)
            {
              idx = (relaxmode == 2) ? R_MOV24B1 : R_MOVL1;
              fix_new_exp (frag_now, offset, 4, &operand->exp, 0, idx);
            }
          break;
        }
    }
  else
    {
      switch (operand->mode & SIZE)
        {
        case L_24:
        case L_32:
          size = 4;
          where = (operand->mode & SIZE) == L_24 ? -1 : 0;
          if (relaxmode == 2)
            idx = R_MOV24B1;
          else if (relaxmode == 1)
            idx = R_MOVL1;
          else
            idx = R_RELLONG;
          break;
        default:
          as_bad (_("Can't work out size of operand.\n"));
        case L_16:
          size = 2;
          where = 0;
          if (relaxmode == 2)
            idx = R_MOV16B1;
          else
            idx = R_RELWORD;
          operand->exp.X_add_number =
            ((operand->exp.X_add_number & 0xffff) ^ 0x8000) - 0x8000;
          break;
        case L_8:
          size = 1;
          where = 0;
          idx = R_RELBYTE;
          operand->exp.X_add_number =
            ((operand->exp.X_add_number & 0xff) ^ 0x80) - 0x80;
        }

      fix_new_exp (frag_now,
                   offset + where,
                   size,
                   &operand->exp,
                   0,
                   idx);
    }
}

/* Now we know what sort of opcodes it is, let's build the bytes.  */

static void
build_bytes (this_try, operand)
     struct h8_opcode *this_try;
     struct h8_op *operand;
{
  int i;
  char *output = frag_more (this_try->length);
  op_type *nibble_ptr = this_try->data.nib;
  op_type c;
  unsigned int nibble_count = 0;
  int absat = 0;
  int immat = 0;
  int nib = 0;
  int movb = 0;
  char asnibbles[30];
  char *p = asnibbles;

  if (!(this_try->inbase || Hmode))
    as_warn (_("Opcode `%s' with these operand types not available in H8/300 mode"),
             this_try->name);

  while (*nibble_ptr != E)
    {
      int d;
      c = *nibble_ptr++;

      d = (c & (DST | SRC_IN_DST)) != 0;

      if (c < 16)
        nib = c;
      else
        {
          if (c & (REG | IND | INC | DEC))
            nib = operand[d].reg;

          else if ((c & DISPREG) == (DISPREG))
            nib = dispreg;

          else if (c & ABS)
            {
              operand[d].mode = c;
              absat = nibble_count / 2;
              nib = 0;
            }
          else if (c & (IMM | PCREL | ABS | ABSJMP | DISP))
            {
              operand[d].mode = c;
              immat = nibble_count / 2;
              nib = 0;
            }
          else if (c & IGNORE)
            nib = 0;

          else if (c & DBIT)
            {
              switch (operand[0].exp.X_add_number)
                {
                case 1:
                  nib = c;
                  break;
                case 2:
                  nib = 0x8 | c;
                  break;
                default:
                  as_bad (_("Need #1 or #2 here"));
                }
            }
          else if (c & KBIT)
            {
              switch (operand[0].exp.X_add_number)
                {
                case 1:
                  nib = 0;
                  break;
                case 2:
                  nib = 8;
                  break;
                case 4:
                  if (!Hmode)
                    as_warn (_("#4 not valid on H8/300."));
                  nib = 9;
                  break;

                default:
                  as_bad (_("Need #1 or #2 here"));
                  break;
                }
              /* Stop it making a fix.  */
              operand[0].mode = 0;
            }

          if (c & MEMRELAX)
            operand[d].mode |= MEMRELAX;

          if (c & B31)
            nib |= 0x8;

          if (c & MACREG)
            {
              if (operand[0].mode == MACREG)
                /* stmac has mac[hl] as the first operand.  */
                nib = 2 + operand[0].reg;
              else
                /* ldmac has mac[hl] as the second operand.  */
                nib = 2 + operand[1].reg;
            }
        }
      nibble_count++;

      *p++ = nib;
    }

  /* Disgusting.  Why, oh why didn't someone ask us for advice
     on the assembler format.  */
  if (strcmp (this_try->name, "stm.l") == 0
      || strcmp (this_try->name, "ldm.l") == 0)
    {
      int high, low;
      high = (operand[this_try->name[0] == 'l' ? 1 : 0].reg >> 8) & 0xf;
      low = operand[this_try->name[0] == 'l' ? 1 : 0].reg & 0xf;

      asnibbles[2] = high - low;
      asnibbles[7] = (this_try->name[0] == 'l') ? high : low;
    }

  for (i = 0; i < this_try->length; i++)
    output[i] = (asnibbles[i * 2] << 4) | asnibbles[i * 2 + 1];

  /* Note if this is a movb instruction -- there's a special relaxation
     which only applies to them.  */
  if (strcmp (this_try->name, "mov.b") == 0)
    movb = 1;

  /* Output any fixes.  */
  for (i = 0; i < 2; i++)
    {
      int x = operand[i].mode;

      if (x & (IMM | DISP))
        do_a_fix_imm (output - frag_now->fr_literal + immat,
                      operand + i, (x & MEMRELAX) != 0);

      else if (x & ABS)
        do_a_fix_imm (output - frag_now->fr_literal + absat,
                      operand + i, (x & MEMRELAX) ? movb + 1 : 0);

      else if (x & PCREL)
        {
          int size16 = x & (L_16);
          int where = size16 ? 2 : 1;
          int size = size16 ? 2 : 1;
          int type = size16 ? R_PCRWORD : R_PCRBYTE;
          fixS *fixP;

          check_operand (operand + i, size16 ? 0x7fff : 0x7f, "@");

          if (operand[i].exp.X_add_number & 1)
            as_warn (_("branch operand has odd offset (%lx)\n"),
                     (unsigned long) operand->exp.X_add_number);
#ifndef OBJ_ELF
          /* The COFF port has always been off by one, changing it
             now would be an incompatible change, so we leave it as-is.

             We don't want to do this for ELF as we want to be
             compatible with the proposed ELF format from Hitachi.  */
          operand[i].exp.X_add_number -= 1;
#endif
          operand[i].exp.X_add_number =
            ((operand[i].exp.X_add_number & 0xff) ^ 0x80) - 0x80;

          fixP = fix_new_exp (frag_now,
                              output - frag_now->fr_literal + where,
                              size,
                              &operand[i].exp,
                              1,
                              type);
          fixP->fx_signed = 1;
        }
      else if (x & MEMIND)
        {
          check_operand (operand + i, 0xff, "@@");
          fix_new_exp (frag_now,
                       output - frag_now->fr_literal + 1,
                       1,
                       &operand[i].exp,
                       0,
                       R_MEM_INDIRECT);
        }
      else if (x & ABSJMP)
        {
          int where = 0;

#ifdef OBJ_ELF
          /* To be compatible with the proposed H8 ELF format, we
             want the relocation's offset to point to the first byte
             that will be modified, not to the start of the instruction.  */
          where += 1;
#endif

          /* This jmp may be a jump or a branch.  */

          check_operand (operand + i, Hmode ? 0xffffff : 0xffff, "@");

          if (operand[i].exp.X_add_number & 1)
            as_warn (_("branch operand has odd offset (%lx)\n"),
                     (unsigned long) operand->exp.X_add_number);

          if (!Hmode)
            operand[i].exp.X_add_number =
              ((operand[i].exp.X_add_number & 0xffff) ^ 0x8000) - 0x8000;
          fix_new_exp (frag_now,
                       output - frag_now->fr_literal + where,
                       4,
                       &operand[i].exp,
                       0,
                       R_JMPL1);
        }
    }
}

/* Try to give an intelligent error message for common and simple to
   detect errors.  */

static void
clever_message (opcode, operand)
     struct h8_opcode *opcode;
     struct h8_op *operand;
{
  /* Find out if there was more than one possible opcode.  */

  if ((opcode + 1)->idx != opcode->idx)
    {
      int argn;

      /* Only one opcode of this flavour, try to guess which operand
         didn't match.  */
      for (argn = 0; argn < opcode->noperands; argn++)
        {
          switch (opcode->args.nib[argn])
            {
            case RD16:
              if (operand[argn].mode != RD16)
                {
                  as_bad (_("destination operand must be 16 bit register"));
                  return;

                }
              break;

            case RS8:
              if (operand[argn].mode != RS8)
                {
                  as_bad (_("source operand must be 8 bit register"));
                  return;
                }
              break;

            case ABS16DST:
              if (operand[argn].mode != ABS16DST)
                {
                  as_bad (_("destination operand must be 16bit absolute address"));
                  return;
                }
              break;
            case RD8:
              if (operand[argn].mode != RD8)
                {
                  as_bad (_("destination operand must be 8 bit register"));
                  return;
                }
              break;

            case ABS16SRC:
              if (operand[argn].mode != ABS16SRC)
                {
                  as_bad (_("source operand must be 16bit absolute address"));
                  return;
                }
              break;

            }
        }
    }
  as_bad (_("invalid operands"));
}

/* 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.  */

void
md_assemble (str)
     char *str;
{
  char *op_start;
  char *op_end;
  struct h8_op operand[2];
  struct h8_opcode *opcode;
  struct h8_opcode *prev_opcode;

  char *dot = 0;
  char c;
  int size;

  /* Drop leading whitespace.  */
  while (*str == ' ')
    str++;

  /* Find the op code end.  */
  for (op_start = op_end = str;
       *op_end != 0 && *op_end != ' ';
       op_end++)
    {
      if (*op_end == '.')
        {
          dot = op_end + 1;
          *op_end = 0;
          op_end += 2;
          break;
        }
    }

  if (op_end == op_start)
    {
      as_bad (_("can't find opcode "));
    }
  c = *op_end;

  *op_end = 0;

  opcode = (struct h8_opcode *) hash_find (opcode_hash_control,
                                           op_start);

  if (opcode == NULL)
    {
      as_bad (_("unknown opcode"));
      return;
    }

  /* We used to set input_line_pointer to the result of get_operands,
     but that is wrong.  Our caller assumes we don't change it.  */

  (void) get_operands (opcode->noperands, op_end, operand);
  *op_end = c;
  prev_opcode = opcode;

  size = SN;
  if (dot)
    {
      switch (*dot)
        {
        case 'b':
          size = SB;
          break;

        case 'w':
          size = SW;
          break;

        case 'l':
          size = SL;
          break;
        }
    }
  opcode = get_specific (opcode, operand, size);

  if (opcode == 0)
    {
      /* Couldn't find an opcode which matched the operands.  */
      char *where = frag_more (2);

      where[0] = 0x0;
      where[1] = 0x0;
      clever_message (prev_opcode, operand);

      return;
    }
  if (opcode->size && dot)
    {
      if (opcode->size != *dot)
        {
          as_warn (_("mismatch between opcode size and operand size"));
        }
    }

  build_bytes (opcode, operand);
}

#ifndef BFD_ASSEMBLER
void
tc_crawl_symbol_chain (headers)
     object_headers *headers ATTRIBUTE_UNUSED;
{
  printf (_("call to tc_crawl_symbol_chain \n"));
}
#endif

symbolS *
md_undefined_symbol (name)
     char *name ATTRIBUTE_UNUSED;
{
  return 0;
}

#ifndef BFD_ASSEMBLER
void
tc_headers_hook (headers)
     object_headers *headers ATTRIBUTE_UNUSED;
{
  printf (_("call to tc_headers_hook \n"));
}
#endif

/* Various routines to kill one day */
/* Equal to MAX_PRECISION in atof-ieee.c */
#define MAX_LITTLENUMS 6

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

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

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

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

    case 'x':
    case 'X':
      prec = 6;
      break;

    case 'p':
    case 'P':
      prec = 6;
      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);
  for (wordP = words; prec--;)
    {
      md_number_to_chars (litP, (long) (*wordP++), sizeof (LITTLENUM_TYPE));
      litP += sizeof (LITTLENUM_TYPE);
    }
  return 0;
}
\f
const char *md_shortopts = "";
struct option md_longopts[] = {
  {NULL, no_argument, NULL, 0}
};

size_t md_longopts_size = sizeof (md_longopts);

int
md_parse_option (c, arg)
     int c ATTRIBUTE_UNUSED;
     char *arg ATTRIBUTE_UNUSED;
{
  return 0;
}

void
md_show_usage (stream)
     FILE *stream ATTRIBUTE_UNUSED;
{
}
\f
void tc_aout_fix_to_chars PARAMS ((void));

void
tc_aout_fix_to_chars ()
{
  printf (_("call to tc_aout_fix_to_chars \n"));
  abort ();
}

void
md_convert_frag (headers, seg, fragP)
#ifdef BFD_ASSEMBLER
     bfd *headers ATTRIBUTE_UNUSED;
#else
     object_headers *headers ATTRIBUTE_UNUSED;
#endif
     segT seg ATTRIBUTE_UNUSED;
     fragS *fragP ATTRIBUTE_UNUSED;
{
  printf (_("call to md_convert_frag \n"));
  abort ();
}

#ifdef BFD_ASSEMBLER
valueT
md_section_align (segment, size)
     segT segment;
     valueT size;
{
  int align = bfd_get_section_alignment (stdoutput, segment);
  return ((size + (1 << align) - 1) & (-1 << align));
}
#else
valueT
md_section_align (seg, size)
     segT seg;
     valueT size;
{
  return ((size + (1 << section_alignment[(int) seg]) - 1)
          & (-1 << section_alignment[(int) seg]));
}
#endif


void
md_apply_fix3 (fixP, valP, seg)
     fixS *fixP;
     valueT *valP;
     segT seg ATTRIBUTE_UNUSED;
{
  char *buf = fixP->fx_where + fixP->fx_frag->fr_literal;
  long val = *valP;

  switch (fixP->fx_size)
    {
    case 1:
      *buf++ = val;
      break;
    case 2:
      *buf++ = (val >> 8);
      *buf++ = val;
      break;
    case 4:
      *buf++ = (val >> 24);
      *buf++ = (val >> 16);
      *buf++ = (val >> 8);
      *buf++ = val;
      break;
    default:
      abort ();
    }

  if (fixP->fx_addsy == NULL && fixP->fx_pcrel == 0)
    fixP->fx_done = 1;
}

int
md_estimate_size_before_relax (fragP, segment_type)
     register fragS *fragP ATTRIBUTE_UNUSED;
     register segT segment_type ATTRIBUTE_UNUSED;
{
  printf (_("call tomd_estimate_size_before_relax \n"));
  abort ();
}

/* Put number into target byte order.  */
void
md_number_to_chars (ptr, use, nbytes)
     char *ptr;
     valueT use;
     int nbytes;
{
  number_to_chars_bigendian (ptr, use, nbytes);
}

long
md_pcrel_from (fixP)
     fixS *fixP ATTRIBUTE_UNUSED;
{
  abort ();
}

#ifndef BFD_ASSEMBLER
void
tc_reloc_mangle (fix_ptr, intr, base)
     fixS *fix_ptr;
     struct internal_reloc *intr;
     bfd_vma base;

{
  symbolS *symbol_ptr;

  symbol_ptr = fix_ptr->fx_addsy;

  /* If this relocation is attached to a symbol then it's ok
     to output it.  */
  if (fix_ptr->fx_r_type == TC_CONS_RELOC)
    {
      /* cons likes to create reloc32's whatever the size of the reloc..
       */
      switch (fix_ptr->fx_size)
        {
        case 4:
          intr->r_type = R_RELLONG;
          break;
        case 2:
          intr->r_type = R_RELWORD;
          break;
        case 1:
          intr->r_type = R_RELBYTE;
          break;
        default:
          abort ();
        }
    }
  else
    {
      intr->r_type = fix_ptr->fx_r_type;
    }

  intr->r_vaddr = fix_ptr->fx_frag->fr_address + fix_ptr->fx_where + base;
  intr->r_offset = fix_ptr->fx_offset;

  if (symbol_ptr)
    {
      if (symbol_ptr->sy_number != -1)
        intr->r_symndx = symbol_ptr->sy_number;
      else
        {
          symbolS *segsym;

          /* This case arises when a reference is made to `.'.  */
          segsym = seg_info (S_GET_SEGMENT (symbol_ptr))->dot;
          if (segsym == NULL)
            intr->r_symndx = -1;
          else
            {
              intr->r_symndx = segsym->sy_number;
              intr->r_offset += S_GET_VALUE (symbol_ptr);
            }
        }
    }
  else
    intr->r_symndx = -1;
}
#else /* BFD_ASSEMBLER */
arelent *
tc_gen_reloc (section, fixp)
     asection *section ATTRIBUTE_UNUSED;
     fixS *fixp;
{
  arelent *rel;
  bfd_reloc_code_real_type r_type;

  if (fixp->fx_addsy && fixp->fx_subsy)
    {
      if ((S_GET_SEGMENT (fixp->fx_addsy) != S_GET_SEGMENT (fixp->fx_subsy))
          || S_GET_SEGMENT (fixp->fx_addsy) == undefined_section)
        {
          as_bad_where (fixp->fx_file, fixp->fx_line,
                        "Difference of symbols in different sections is not supported");
          return NULL;
        }
    }

  rel = (arelent *) xmalloc (sizeof (arelent));
  rel->sym_ptr_ptr = (asymbol **) xmalloc (sizeof (asymbol *));
  *rel->sym_ptr_ptr = symbol_get_bfdsym (fixp->fx_addsy);
  rel->address = fixp->fx_frag->fr_address + fixp->fx_where;
  rel->addend = fixp->fx_offset;

  r_type = fixp->fx_r_type;

#define DEBUG 0
#if DEBUG
  fprintf (stderr, "%s\n", bfd_get_reloc_code_name (r_type));
  fflush(stderr);
#endif
  rel->howto = bfd_reloc_type_lookup (stdoutput, r_type);
  if (rel->howto == NULL)
    {
      as_bad_where (fixp->fx_file, fixp->fx_line,
                    _("Cannot represent relocation type %s"),
                    bfd_get_reloc_code_name (r_type));
      return NULL;
    }

  return rel;
}
#endif