xref: /openbsd-src/gnu/usr.bin/binutils/gas/config/tc-a29k.c (revision c074d1c999f3e07019cd5e9a2f190b057ef3b935)

/* tc-a29k.c -- Assemble for the AMD 29000.
   Copyright 1989, 1990, 1991, 1992, 1993, 1994, 1995, 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.  */

/* John Gilmore has reorganized this module somewhat, to make it easier
   to convert it to new machines' assemblers as desired.  There was too
   much bloody rewriting required before.  There still probably is.  */

#include "as.h"
#include "safe-ctype.h"

#include "opcode/a29k.h"

/* Make it easier to clone this machine desc into another one.  */
#define	machine_opcode	a29k_opcode
#define	machine_opcodes	a29k_opcodes
#define	machine_ip	a29k_ip
#define	machine_it	a29k_it

#define	IMMEDIATE_BIT	0x01000000	/* Turns RB into Immediate */
#define	ABSOLUTE_BIT	0x01000000	/* Turns PC-relative to Absolute */
#define	CE_BIT		0x00800000	/* Coprocessor enable in LOAD */
#define	UI_BIT		0x00000080	/* Unsigned integer in CONVERT */

/* handle of the OPCODE hash table */
static struct hash_control *op_hash = NULL;

struct machine_it
  {
    char *error;
    unsigned long opcode;
    struct nlist *nlistp;
    expressionS exp;
    int pcrel;
    int reloc_offset;		/* Offset of reloc within insn */

    int reloc;
  }
the_insn;

static void machine_ip PARAMS ((char *str));
/* static void print_insn PARAMS ((struct machine_it *insn)); */
#ifndef OBJ_COFF
static void s_data1 PARAMS ((void));
static void s_use PARAMS ((int));
#endif
static void insert_sreg PARAMS ((char *, int));
static void define_some_regs PARAMS ((void));
static char *parse_operand PARAMS ((char *, expressionS *, int));

const pseudo_typeS
md_pseudo_table[] =
{
  {"align", s_align_bytes, 4},
  {"block", s_space, 0},
  {"cputype", s_ignore, 0},	/* CPU as 29000 or 29050 */
  {"reg", s_lsym, 0},		/* Register equate, same as equ */
  {"space", s_ignore, 0},	/* Listing control */
  {"sect", s_ignore, 0},	/* Creation of coff sections */
#ifndef OBJ_COFF
  /* We can do this right with coff.  */
  {"use", s_use, 0},
#endif
  {"word", cons, 4},
  {NULL, 0, 0},
};

#if defined(BFD_HEADERS)
#ifdef RELSZ
const int md_reloc_size = RELSZ;	/* Coff headers */
#else
const int md_reloc_size = 12;		/* something else headers */
#endif
#else
const int md_reloc_size = 12;		/* Not bfdized*/
#endif

/* This array holds the chars that always start a comment.  If the
   pre-processor is disabled, these aren't very useful */
const char comment_chars[] = ";";

/* This array holds the chars that only start a comment at the beginning of
   a line.  If the line seems to have the form '# 123 filename'
   .line and .file directives will appear in the pre-processed output */
/* Note that input_file.c hand checks for '#' at the beginning of the
   first line of the input file.  This is because the compiler outputs
   #NO_APP at the beginning of its output.  */
/* Also note that comments like this one will always work */
const char line_comment_chars[] = "#";

/* We needed an unused char for line separation to work around the
   lack of macros, using sed and such.  */
const char line_separator_chars[] = "@";

/* Chars that can be used to separate mant from exp in floating point nums */
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";

/* Also be aware that MAXIMUM_NUMBER_OF_CHARS_FOR_FLOAT may have to be
   changed in read.c.  Ideally it shouldn't have to know about it at
   all, but nothing is ideal around here.  */

/*
 *  anull bit - causes the branch delay slot instructions to not be executed
 */
#define ANNUL       (1 << 29)

#ifndef OBJ_COFF

static void
s_use (ignore)
     int ignore;
{
  if (strncmp (input_line_pointer, ".text", 5) == 0)
    {
      input_line_pointer += 5;
      s_text (0);
      return;
    }
  if (strncmp (input_line_pointer, ".data", 5) == 0)
    {
      input_line_pointer += 5;
      s_data (0);
      return;
    }
  if (strncmp (input_line_pointer, ".data1", 6) == 0)
    {
      input_line_pointer += 6;
      s_data1 ();
      return;
    }
  /* Literals can't go in the text segment because you can't read from
     instruction memory on some 29k's.  So, into initialized data.  */
  if (strncmp (input_line_pointer, ".lit", 4) == 0)
    {
      input_line_pointer += 4;
      subseg_set (SEG_DATA, 200);
      demand_empty_rest_of_line ();
      return;
    }

  as_bad (_("Unknown segment type"));
  demand_empty_rest_of_line ();
}

static void
s_data1 ()
{
  subseg_set (SEG_DATA, 1);
  demand_empty_rest_of_line ();
}

#endif /* OBJ_COFF */

/* Install symbol definition that maps REGNAME to REGNO.
   FIXME-SOON:  These are not recognized in mixed case.  */

static void
insert_sreg (regname, regnum)
     char *regname;
     int regnum;
{
  /* FIXME-SOON, put something in these syms so they won't be output
     to the symbol table of the resulting object file.  */

  /* Must be large enough to hold the names of the special registers.  */
  char buf[80];
  int i;

  symbol_table_insert (symbol_new (regname, SEG_REGISTER, (valueT) regnum,
				   &zero_address_frag));
  for (i = 0; regname[i]; i++)
    buf[i] = TOUPPER (regname[i]);
  buf[i] = '\0';

  symbol_table_insert (symbol_new (buf, SEG_REGISTER, (valueT) regnum,
				   &zero_address_frag));
}

/* Install symbol definitions for assorted special registers.
   See ASM29K Ref page 2-9.  */

static void
define_some_regs ()
{
#define SREG	256

  /* Protected special-purpose register names */
  insert_sreg ("vab", SREG + 0);
  insert_sreg ("ops", SREG + 1);
  insert_sreg ("cps", SREG + 2);
  insert_sreg ("cfg", SREG + 3);
  insert_sreg ("cha", SREG + 4);
  insert_sreg ("chd", SREG + 5);
  insert_sreg ("chc", SREG + 6);
  insert_sreg ("rbp", SREG + 7);
  insert_sreg ("tmc", SREG + 8);
  insert_sreg ("tmr", SREG + 9);
  insert_sreg ("pc0", SREG + 10);
  insert_sreg ("pc1", SREG + 11);
  insert_sreg ("pc2", SREG + 12);
  insert_sreg ("mmu", SREG + 13);
  insert_sreg ("lru", SREG + 14);

  /* Additional protected special-purpose registers for the 29050 */
  insert_sreg ("rsn",  SREG + 15);
  insert_sreg ("rma0", SREG + 16);
  insert_sreg ("rmc0", SREG + 17);
  insert_sreg ("rma1", SREG + 18);
  insert_sreg ("rmc1", SREG + 19);
  insert_sreg ("spc0", SREG + 20);
  insert_sreg ("spc1", SREG + 21);
  insert_sreg ("spc2", SREG + 22);
  insert_sreg ("iba0", SREG + 23);
  insert_sreg ("ibc0", SREG + 24);
  insert_sreg ("iba1", SREG + 25);
  insert_sreg ("ibc1", SREG + 26);

  /* Additional registers for the 29040.  */
  insert_sreg ("dba", SREG + 27);
  insert_sreg ("dbc", SREG + 28);
  insert_sreg ("cir", SREG + 29);
  insert_sreg ("cdr", SREG + 30);

  /* Unprotected special-purpose register names */
  insert_sreg ("ipc", SREG + 128);
  insert_sreg ("ipa", SREG + 129);
  insert_sreg ("ipb", SREG + 130);
  insert_sreg ("q", SREG + 131);
  insert_sreg ("alu", SREG + 132);
  insert_sreg ("bp", SREG + 133);
  insert_sreg ("fc", SREG + 134);
  insert_sreg ("cr", SREG + 135);
  insert_sreg ("fpe", SREG + 160);
  insert_sreg ("inte", SREG + 161);
  insert_sreg ("fps", SREG + 162);
  /*  "",    SREG+163);	  Reserved */
  insert_sreg ("exop", SREG + 164);
}

/* 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 ()
{
  register const char *retval = NULL;
  int lose = 0;
  register int skipnext = 0;
  register unsigned int i;
  register char *strend, *strend2;

  /* Hash up all the opcodes for fast use later.  */

  op_hash = hash_new ();

  for (i = 0; i < num_opcodes; i++)
    {
      const char *name = machine_opcodes[i].name;

      if (skipnext)
	{
	  skipnext = 0;
	  continue;
	}

      /* Hack to avoid multiple opcode entries.  We pre-locate all the
	 variations (b/i field and P/A field) and handle them.  */

      if (!strcmp (name, machine_opcodes[i + 1].name))
	{
	  if ((machine_opcodes[i].opcode & 0x01000000) != 0
	      || (machine_opcodes[i + 1].opcode & 0x01000000) == 0
	      || ((machine_opcodes[i].opcode | 0x01000000)
		  != machine_opcodes[i + 1].opcode))
	    goto bad_table;
	  strend = machine_opcodes[i].args + strlen (machine_opcodes[i].args) - 1;
	  strend2 = machine_opcodes[i + 1].args + strlen (machine_opcodes[i + 1].args) - 1;
	  switch (*strend)
	    {
	    case 'b':
	      if (*strend2 != 'i')
		goto bad_table;
	      break;
	    case 'P':
	      if (*strend2 != 'A')
		goto bad_table;
	      break;
	    default:
	    bad_table:
	      fprintf (stderr, "internal error: can't handle opcode %s\n",
		       name);
	      lose = 1;
	    }

	  /* OK, this is an i/b or A/P pair.  We skip the
	     higher-valued one, and let the code for operand checking
	     handle OR-ing in the bit.  */
	  skipnext = 1;
	}

      retval = hash_insert (op_hash, name, (PTR) &machine_opcodes[i]);
      if (retval != NULL)
	{
	  fprintf (stderr, "internal error: can't hash `%s': %s\n",
		   machine_opcodes[i].name, retval);
	  lose = 1;
	}
    }

  if (lose)
    as_fatal (_("Broken assembler.  No assembly attempted."));

  define_some_regs ();
}

/* Assemble a single instruction.  Its label has already been handled
   by the generic front end.  We just parse opcode and operands, and
   produce the bytes of data and relocation.  */

void
md_assemble (str)
     char *str;
{
  char *toP;

  know (str);
  machine_ip (str);
  toP = frag_more (4);
  /* put out the opcode */
  md_number_to_chars (toP, the_insn.opcode, 4);

  /* put out the symbol-dependent stuff */
  if (the_insn.reloc != NO_RELOC)
    {
      fix_new_exp (frag_now,
		   (toP - frag_now->fr_literal + the_insn.reloc_offset),
		   4,		/* size */
		   &the_insn.exp,
		   the_insn.pcrel,
		   the_insn.reloc);
    }
}

static char *
parse_operand (s, operandp, opt)
     char *s;
     expressionS *operandp;
     int opt;
{
  char *save = input_line_pointer;
  char *new;

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

/* Instruction parsing.  Takes a string containing the opcode.
   Operands are at input_line_pointer.  Output is in the_insn.
   Warnings or errors are generated.  */

static void
machine_ip (str)
     char *str;
{
  char *s;
  const char *args;
  struct machine_opcode *insn;
  char *argsStart;
  unsigned long opcode;
  expressionS the_operand;
  expressionS *operand = &the_operand;
  unsigned int reg;

  /* Must handle `div0' opcode.  */
  s = str;
  if (ISALPHA (*s))
    for (; ISALNUM (*s); ++s)
      *s = TOLOWER (*s);

  switch (*s)
    {
    case '\0':
      break;

    case ' ':			/* FIXME-SOMEDAY more whitespace */
      *s++ = '\0';
      break;

    default:
      as_bad (_("Unknown opcode: `%s'"), str);
      return;
    }
  if ((insn = (struct machine_opcode *) hash_find (op_hash, str)) == NULL)
    {
      as_bad (_("Unknown opcode `%s'."), str);
      return;
    }
  argsStart = s;
  opcode = insn->opcode;
  memset (&the_insn, '\0', sizeof (the_insn));
  the_insn.reloc = NO_RELOC;

  /* Build the opcode, checking as we go to make sure that the
     operands match.

     If an operand matches, we modify the_insn or opcode appropriately,
     and do a "continue".  If an operand fails to match, we "break".  */

  if (insn->args[0] != '\0')
    {
      /* Prime the pump.  */
      s = parse_operand (s, operand, insn->args[0] == 'I');
    }

  for (args = insn->args;; ++args)
    {
      switch (*args)
	{

	case '\0':		/* end of args */
	  if (*s == '\0')
	    {
	      /* We are truly done.  */
	      the_insn.opcode = opcode;
	      return;
	    }
	  as_bad (_("Too many operands: %s"), s);
	  break;

	case ',':		/* Must match a comma */
	  if (*s++ == ',')
	    {
	      /* Parse next operand.  */
	      s = parse_operand (s, operand, args[1] == 'I');
	      continue;
	    }
	  break;

	case 'v':		/* Trap numbers (immediate field) */
	  if (operand->X_op == O_constant)
	    {
	      if (operand->X_add_number < 256)
		{
		  opcode |= (operand->X_add_number << 16);
		  continue;
		}
	      else
		{
		  as_bad (_("Immediate value of %ld is too large"),
			  (long) operand->X_add_number);
		  continue;
		}
	    }
	  the_insn.reloc = RELOC_8;
	  the_insn.reloc_offset = 1;	/* BIG-ENDIAN Byte 1 of insn */
	  the_insn.exp = *operand;
	  continue;

	case 'b':		/* A general register or 8-bit immediate */
	case 'i':
	  /* We treat the two cases identically since we mashed
	     them together in the opcode table.  */
	  if (operand->X_op == O_register)
	    goto general_reg;

	  /* Make sure the 'i' case really exists.  */
	  if ((insn->opcode | IMMEDIATE_BIT) != (insn + 1)->opcode)
	    break;

	  opcode |= IMMEDIATE_BIT;
	  if (operand->X_op == O_constant)
	    {
	      if (operand->X_add_number < 256)
		{
		  opcode |= operand->X_add_number;
		  continue;
		}
	      else
		{
		  as_bad (_("Immediate value of %ld is too large"),
			  (long) operand->X_add_number);
		  continue;
		}
	    }
	  the_insn.reloc = RELOC_8;
	  the_insn.reloc_offset = 3;	/* BIG-ENDIAN Byte 3 of insn */
	  the_insn.exp = *operand;
	  continue;

	case 'a':		/* next operand must be a register */
	case 'c':
	general_reg:
	  /* lrNNN or grNNN or %%expr or a user-def register name */
	  if (operand->X_op != O_register)
	    break;		/* Only registers */
	  know (operand->X_add_symbol == 0);
	  know (operand->X_op_symbol == 0);
	  reg = operand->X_add_number;
	  if (reg >= SREG)
	    break;		/* No special registers */

	  /* Got the register, now figure out where it goes in the
	     opcode.  */
	  switch (*args)
	    {
	    case 'a':
	      opcode |= reg << 8;
	      continue;

	    case 'b':
	    case 'i':
	      opcode |= reg;
	      continue;

	    case 'c':
	      opcode |= reg << 16;
	      continue;
	    }
	  as_fatal (_("failed sanity check."));
	  break;

	case 'x':		/* 16 bit constant, zero-extended */
	case 'X':		/* 16 bit constant, one-extended */
	  if (operand->X_op == O_constant)
	    {
	      opcode |= (operand->X_add_number & 0xFF) << 0 |
		((operand->X_add_number & 0xFF00) << 8);
	      continue;
	    }
	  the_insn.reloc = RELOC_CONST;
	  the_insn.exp = *operand;
	  continue;

	case 'h':
	  if (operand->X_op == O_constant)
	    {
	      opcode |= (operand->X_add_number & 0x00FF0000) >> 16 |
		(((unsigned long) operand->X_add_number
		  /* avoid sign ext */  & 0xFF000000) >> 8);
	      continue;
	    }
	  the_insn.reloc = RELOC_CONSTH;
	  the_insn.exp = *operand;
	  continue;

	case 'P':		/* PC-relative jump address */
	case 'A':		/* Absolute jump address */
	  /* These two are treated together since we folded the
	     opcode table entries together.  */
	  if (operand->X_op == O_constant)
	    {
	      /* Make sure the 'A' case really exists.  */
	      if ((insn->opcode | ABSOLUTE_BIT) != (insn + 1)->opcode)
		break;
	      {
		bfd_vma v, mask;
		mask = 0x1ffff;
		v = operand->X_add_number & ~ mask;
		if (v)
		  as_bad ("call/jmp target out of range");
	      }
	      opcode |= ABSOLUTE_BIT |
		(operand->X_add_number & 0x0003FC00) << 6 |
		((operand->X_add_number & 0x000003FC) >> 2);
	      continue;
	    }
	  the_insn.reloc = RELOC_JUMPTARG;
	  the_insn.exp = *operand;
	  the_insn.pcrel = 1;	/* Assume PC-relative jump */
	  /* FIXME-SOON, Do we figure out whether abs later, after
             know sym val? */
	  continue;

	case 'e':		/* Coprocessor enable bit for LOAD/STORE insn */
	  if (operand->X_op == O_constant)
	    {
	      if (operand->X_add_number == 0)
		continue;
	      if (operand->X_add_number == 1)
		{
		  opcode |= CE_BIT;
		  continue;
		}
	    }
	  break;

	case 'n':		/* Control bits for LOAD/STORE instructions */
	  if (operand->X_op == O_constant &&
	      operand->X_add_number < 128)
	    {
	      opcode |= (operand->X_add_number << 16);
	      continue;
	    }
	  break;

	case 's':		/* Special register number */
	  if (operand->X_op != O_register)
	    break;		/* Only registers */
	  if (operand->X_add_number < SREG)
	    break;		/* Not a special register */
	  opcode |= (operand->X_add_number & 0xFF) << 8;
	  continue;

	case 'u':		/* UI bit of CONVERT */
	  if (operand->X_op == O_constant)
	    {
	      if (operand->X_add_number == 0)
		continue;
	      if (operand->X_add_number == 1)
		{
		  opcode |= UI_BIT;
		  continue;
		}
	    }
	  break;

	case 'r':		/* RND bits of CONVERT */
	  if (operand->X_op == O_constant &&
	      operand->X_add_number < 8)
	    {
	      opcode |= operand->X_add_number << 4;
	      continue;
	    }
	  break;

	case 'I':		/* ID bits of INV and IRETINV.  */
	  /* This operand is optional.  */
	  if (operand->X_op == O_absent)
	    continue;
	  else if (operand->X_op == O_constant
		   && operand->X_add_number < 4)
	    {
	      opcode |= operand->X_add_number << 16;
	      continue;
	    }
	  break;

	case 'd':		/* FD bits of CONVERT */
	  if (operand->X_op == O_constant &&
	      operand->X_add_number < 4)
	    {
	      opcode |= operand->X_add_number << 2;
	      continue;
	    }
	  break;

	case 'f':		/* FS bits of CONVERT */
	  if (operand->X_op == O_constant &&
	      operand->X_add_number < 4)
	    {
	      opcode |= operand->X_add_number << 0;
	      continue;
	    }
	  break;

	case 'C':
	  if (operand->X_op == O_constant &&
	      operand->X_add_number < 4)
	    {
	      opcode |= operand->X_add_number << 16;
	      continue;
	    }
	  break;

	case 'F':
	  if (operand->X_op == O_constant &&
	      operand->X_add_number < 16)
	    {
	      opcode |= operand->X_add_number << 18;
	      continue;
	    }
	  break;

	default:
	  BAD_CASE (*args);
	}
      /* Types or values of args don't match.  */
      as_bad ("Invalid operands");
      return;
    }
}

/* This is identical to the md_atof in m68k.c.  I think this is right,
   but I'm not sure.

   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.  */

/* Equal to MAX_PRECISION in atof-ieee.c */
#define MAX_LITTLENUMS 6

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, (valueT) (*wordP++), sizeof (LITTLENUM_TYPE));
      litP += sizeof (LITTLENUM_TYPE);
    }
  return 0;
}

/*
 * Write out big-endian.
 */
void
md_number_to_chars (buf, val, n)
     char *buf;
     valueT val;
     int n;
{
  number_to_chars_bigendian (buf, val, n);
}

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

  fixP->fx_addnumber = val;	/* Remember value for emit_reloc.  */

  know (fixP->fx_size == 4);
  know (fixP->fx_r_type < NO_RELOC);

  /* This is a hack.  There should be a better way to handle this.  */
  if (fixP->fx_r_type == RELOC_WDISP30 && fixP->fx_addsy)
    val += fixP->fx_where + fixP->fx_frag->fr_address;

  switch (fixP->fx_r_type)
    {
    case RELOC_32:
      buf[0] = val >> 24;
      buf[1] = val >> 16;
      buf[2] = val >> 8;
      buf[3] = val;
      break;

    case RELOC_8:
      buf[0] = val;
      break;

    case RELOC_WDISP30:
      val = (val >> 2) + 1;
      buf[0] |= (val >> 24) & 0x3f;
      buf[1] = (val >> 16);
      buf[2] = val >> 8;
      buf[3] = val;
      break;

    case RELOC_HI22:
      buf[1] |= (val >> 26) & 0x3f;
      buf[2] = val >> 18;
      buf[3] = val >> 10;
      break;

    case RELOC_LO10:
      buf[2] |= (val >> 8) & 0x03;
      buf[3] = val;
      break;

    case RELOC_BASE13:
      buf[2] |= (val >> 8) & 0x1f;
      buf[3] = val;
      break;

    case RELOC_WDISP22:
      val = (val >> 2) + 1;
      /* FALLTHROUGH */
    case RELOC_BASE22:
      buf[1] |= (val >> 16) & 0x3f;
      buf[2] = val >> 8;
      buf[3] = val;
      break;

    case RELOC_JUMPTARG:	/* 00XX00XX pattern in a word */
      if (!fixP->fx_done)
	{
	  /* The linker tries to support both AMD and old GNU style
             R_IREL relocs.  That means that if the addend is exactly
             the negative of the address within the section, the
             linker will not handle it correctly.  */
	  if (fixP->fx_pcrel
	      && val != 0
	      && val == - (fixP->fx_frag->fr_address + fixP->fx_where))
	    as_bad_where
	      (fixP->fx_file, fixP->fx_line,
	       "the linker will not handle this relocation correctly");
	}
      else if (fixP->fx_pcrel)
	{
	  long v = val >> 17;

	  if (v != 0 && v != -1)
	    as_bad_where (fixP->fx_file, fixP->fx_line,
			  "call/jmp target out of range");
	}
      else
	/* This case was supposed to be handled in machine_ip.  */
	abort ();
      buf[1] = val >> 10;	/* Holds bits 0003FFFC of address */
      buf[3] = val >> 2;
      break;

    case RELOC_CONST:		/* 00XX00XX pattern in a word */
      buf[1] = val >> 8;	/* Holds bits 0000XXXX */
      buf[3] = val;
      break;

    case RELOC_CONSTH:		/* 00XX00XX pattern in a word */
      buf[1] = val >> 24;	/* Holds bits XXXX0000 */
      buf[3] = val >> 16;
      break;

    case NO_RELOC:
    default:
      as_bad (_("bad relocation type: 0x%02x"), fixP->fx_r_type);
      break;
    }

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

#ifdef OBJ_COFF
short
tc_coff_fix2rtype (fixP)
     fixS *fixP;
{

  switch (fixP->fx_r_type)
    {
    case RELOC_32:
      return (R_WORD);
    case RELOC_8:
      return (R_BYTE);
    case RELOC_CONST:
      return (R_ILOHALF);
    case RELOC_CONSTH:
      return (R_IHIHALF);
    case RELOC_JUMPTARG:
      return (R_IREL);
    default:
      printf (_("need %o3\n"), fixP->fx_r_type);
      abort ();
    }				/* switch on type */

  return (0);
}

#endif /* OBJ_COFF */

/* should never be called for 29k */
void
md_convert_frag (headers, seg, fragP)
     object_headers *headers ATTRIBUTE_UNUSED;
     segT seg ATTRIBUTE_UNUSED;
     register fragS *fragP ATTRIBUTE_UNUSED;
{
  as_fatal (_("a29k_convert_frag\n"));
}

/* should never be called for a29k */
int
md_estimate_size_before_relax (fragP, segtype)
     register fragS *fragP ATTRIBUTE_UNUSED;
     segT segtype ATTRIBUTE_UNUSED;
{
  as_fatal (_("a29k_estimate_size_before_relax\n"));
  return 0;
}

#if 0
/* for debugging only */
static void
print_insn (insn)
     struct machine_it *insn;
{
  char *Reloc[] =
  {
    "RELOC_8",
    "RELOC_16",
    "RELOC_32",
    "RELOC_DISP8",
    "RELOC_DISP16",
    "RELOC_DISP32",
    "RELOC_WDISP30",
    "RELOC_WDISP22",
    "RELOC_HI22",
    "RELOC_22",
    "RELOC_13",
    "RELOC_LO10",
    "RELOC_SFA_BASE",
    "RELOC_SFA_OFF13",
    "RELOC_BASE10",
    "RELOC_BASE13",
    "RELOC_BASE22",
    "RELOC_PC10",
    "RELOC_PC22",
    "RELOC_JMP_TBL",
    "RELOC_SEGOFF16",
    "RELOC_GLOB_DAT",
    "RELOC_JMP_SLOT",
    "RELOC_RELATIVE",
    "NO_RELOC"
  };

  if (insn->error)
    {
      fprintf (stderr, "ERROR: %s\n");
    }
  fprintf (stderr, "opcode=0x%08x\n", insn->opcode);
  fprintf (stderr, "reloc = %s\n", Reloc[insn->reloc]);
  fprintf (stderr, "exp =  {\n");
  fprintf (stderr, "\t\tX_add_symbol = %s\n",
	   insn->exp.X_add_symbol ?
	   (S_GET_NAME (insn->exp.X_add_symbol) ?
	    S_GET_NAME (insn->exp.X_add_symbol) : "???") : "0");
  fprintf (stderr, "\t\tX_op_symbol = %s\n",
	   insn->exp.X_op_symbol ?
	   (S_GET_NAME (insn->exp.X_op_symbol) ?
	    S_GET_NAME (insn->exp.X_op_symbol) : "???") : "0");
  fprintf (stderr, "\t\tX_add_number = %d\n",
	   insn->exp.X_add_number);
  fprintf (stderr, "}\n");
}

#endif

/* Translate internal representation of relocation info to target format.

   On sparc/29k: first 4 bytes are normal unsigned long address, next three
   bytes are index, most sig. byte first.  Byte 7 is broken up with
   bit 7 as external, bits 6 & 5 unused, and the lower
   five bits as relocation type.  Next 4 bytes are long addend.  */
/* Thanx and a tip of the hat to Michael Bloom, mb@ttidca.tti.com */

#ifdef OBJ_AOUT

void
tc_aout_fix_to_chars (where, fixP, segment_address_in_file)
     char *where;
     fixS *fixP;
     relax_addressT segment_address_in_file;
{
  long r_symbolnum;

  know (fixP->fx_r_type < NO_RELOC);
  know (fixP->fx_addsy != NULL);

  md_number_to_chars (where,
       fixP->fx_frag->fr_address + fixP->fx_where - segment_address_in_file,
		      4);

  r_symbolnum = (S_IS_DEFINED (fixP->fx_addsy)
		 ? S_GET_TYPE (fixP->fx_addsy)
		 : fixP->fx_addsy->sy_number);

  where[4] = (r_symbolnum >> 16) & 0x0ff;
  where[5] = (r_symbolnum >> 8) & 0x0ff;
  where[6] = r_symbolnum & 0x0ff;
  where[7] = (((!S_IS_DEFINED (fixP->fx_addsy)) << 7) & 0x80) | (0 & 0x60) | (fixP->fx_r_type & 0x1F);
  /* Also easy */
  md_number_to_chars (&where[8], fixP->fx_addnumber, 4);
}

#endif /* OBJ_AOUT */

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;
{
}

/* This is called when a line is unrecognized.  This is used to handle
   definitions of a29k style local labels.  */

int
a29k_unrecognized_line (c)
     int c;
{
  int lab;
  char *s;

  if (c != '$'
      || ! ISDIGIT (input_line_pointer[0]))
    return 0;

  s = input_line_pointer;

  lab = 0;
  while (ISDIGIT (*s))
    {
      lab = lab * 10 + *s - '0';
      ++s;
    }

  if (*s != ':')
    {
      /* Not a label definition.  */
      return 0;
    }

  if (dollar_label_defined (lab))
    {
      as_bad (_("label \"$%d\" redefined"), lab);
      return 0;
    }

  define_dollar_label (lab);
  colon (dollar_label_name (lab, 0));
  input_line_pointer = s + 1;

  return 1;
}

/* Default the values of symbols known that should be "predefined".  We
   don't bother to predefine them unless you actually use one, since there
   are a lot of them.  */

symbolS *
md_undefined_symbol (name)
     char *name;
{
  long regnum;
  char testbuf[5 + /*SLOP*/ 5];

  if (name[0] == 'g' || name[0] == 'G'
      || name[0] == 'l' || name[0] == 'L'
      || name[0] == 's' || name[0] == 'S')
    {
      /* Perhaps a global or local register name */
      if (name[1] == 'r' || name[1] == 'R')
	{
	  long maxreg;

	  /* Parse the number, make sure it has no extra zeroes or
	     trailing chars.  */
	  regnum = atol (&name[2]);

	  if (name[0] == 's' || name[0] == 'S')
	    maxreg = 255;
	  else
	    maxreg = 127;
	  if (regnum > maxreg)
	    return NULL;

	  sprintf (testbuf, "%ld", regnum);
	  if (strcmp (testbuf, &name[2]) != 0)
	    return NULL;	/* gr007 or lr7foo or whatever */

	  /* We have a wiener!  Define and return a new symbol for it.  */
	  if (name[0] == 'l' || name[0] == 'L')
	    regnum += 128;
	  else if (name[0] == 's' || name[0] == 'S')
	    regnum += SREG;
	  return (symbol_new (name, SEG_REGISTER, (valueT) regnum,
			      &zero_address_frag));
	}
    }

  return NULL;
}

/* Parse an operand that is machine-specific.  */

void
md_operand (expressionP)
     expressionS *expressionP;
{

  if (input_line_pointer[0] == '%' && input_line_pointer[1] == '%')
    {
      /* We have a numeric register expression.  No biggy.  */
      input_line_pointer += 2;	/* Skip %% */
      (void) expression (expressionP);
      if (expressionP->X_op != O_constant
	  || expressionP->X_add_number > 255)
	as_bad (_("Invalid expression after %%%%\n"));
      expressionP->X_op = O_register;
    }
  else if (input_line_pointer[0] == '&')
    {
      /* We are taking the 'address' of a register...this one is not
	 in the manual, but it *is* in traps/fpsymbol.h!  What they
	 seem to want is the register number, as an absolute number.  */
      input_line_pointer++;	/* Skip & */
      (void) expression (expressionP);
      if (expressionP->X_op != O_register)
	as_bad (_("Invalid register in & expression"));
      else
	expressionP->X_op = O_constant;
    }
  else if (input_line_pointer[0] == '$'
	   && ISDIGIT (input_line_pointer[1]))
    {
      long lab;
      char *name;
      symbolS *sym;

      /* This is a local label.  */
      ++input_line_pointer;
      lab = (long) get_absolute_expression ();
      if (dollar_label_defined (lab))
	{
	  name = dollar_label_name (lab, 0);
	  sym = symbol_find (name);
	}
      else
	{
	  name = dollar_label_name (lab, 1);
	  sym = symbol_find_or_make (name);
	}

      expressionP->X_op = O_symbol;
      expressionP->X_add_symbol = sym;
      expressionP->X_add_number = 0;
    }
  else if (input_line_pointer[0] == '$')
    {
      char *s;
      char type;
      int fieldnum, fieldlimit;
      LITTLENUM_TYPE floatbuf[8];

      /* $float(), $doubleN(), or $extendN() convert floating values
	 to integers.  */

      s = input_line_pointer;

      ++s;

      fieldnum = 0;
      if (strncmp (s, "double", sizeof "double" - 1) == 0)
	{
	  s += sizeof "double" - 1;
	  type = 'd';
	  fieldlimit = 2;
	}
      else if (strncmp (s, "float", sizeof "float" - 1) == 0)
	{
	  s += sizeof "float" - 1;
	  type = 'f';
	  fieldlimit = 1;
	}
      else if (strncmp (s, "extend", sizeof "extend" - 1) == 0)
	{
	  s += sizeof "extend" - 1;
	  type = 'x';
	  fieldlimit = 4;
	}
      else
	{
	  return;
	}

      if (ISDIGIT (*s))
	{
	  fieldnum = *s - '0';
	  ++s;
	}
      if (fieldnum >= fieldlimit)
	return;

      SKIP_WHITESPACE ();
      if (*s != '(')
	return;
      ++s;
      SKIP_WHITESPACE ();

      s = atof_ieee (s, type, floatbuf);
      if (s == NULL)
	return;
      s = s;

      SKIP_WHITESPACE ();
      if (*s != ')')
	return;
      ++s;
      SKIP_WHITESPACE ();

      input_line_pointer = s;
      expressionP->X_op = O_constant;
      expressionP->X_unsigned = 1;
      expressionP->X_add_number = ((floatbuf[fieldnum * 2]
				    << LITTLENUM_NUMBER_OF_BITS)
				   + floatbuf[fieldnum * 2 + 1]);
    }
}

/* Round up a section size to the appropriate boundary.  */
valueT
md_section_align (segment, size)
     segT segment ATTRIBUTE_UNUSED;
     valueT size;
{
  return size;			/* Byte alignment is fine */
}

/* Exactly what point is a PC-relative offset relative TO?
   On the 29000, they're relative to the address of the instruction,
   which we have set up as the address of the fixup too.  */
long
md_pcrel_from (fixP)
     fixS *fixP;
{
  return fixP->fx_where + fixP->fx_frag->fr_address;
}