tc-ns32k.c

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		__LINE__, __FILE__);
    }
}

/* Fast bitfiddling support.  */
/* Mask used to zero bitfield before oring in the true field.  */

static unsigned long l_mask[] =
{
  0xffffffff, 0xfffffffe, 0xfffffffc, 0xfffffff8,
  0xfffffff0, 0xffffffe0, 0xffffffc0, 0xffffff80,
  0xffffff00, 0xfffffe00, 0xfffffc00, 0xfffff800,
  0xfffff000, 0xffffe000, 0xffffc000, 0xffff8000,
  0xffff0000, 0xfffe0000, 0xfffc0000, 0xfff80000,
  0xfff00000, 0xffe00000, 0xffc00000, 0xff800000,
  0xff000000, 0xfe000000, 0xfc000000, 0xf8000000,
  0xf0000000, 0xe0000000, 0xc0000000, 0x80000000,
};
static unsigned long r_mask[] =
{
  0x00000000, 0x00000001, 0x00000003, 0x00000007,
  0x0000000f, 0x0000001f, 0x0000003f, 0x0000007f,
  0x000000ff, 0x000001ff, 0x000003ff, 0x000007ff,
  0x00000fff, 0x00001fff, 0x00003fff, 0x00007fff,
  0x0000ffff, 0x0001ffff, 0x0003ffff, 0x0007ffff,
  0x000fffff, 0x001fffff, 0x003fffff, 0x007fffff,
  0x00ffffff, 0x01ffffff, 0x03ffffff, 0x07ffffff,
  0x0fffffff, 0x1fffffff, 0x3fffffff, 0x7fffffff,
};
#define MASK_BITS 31
/* Insert bitfield described by field_ptr and val at buf
   This routine is written for modification of the first 4 bytes pointed
   to by buf, to yield speed.
   The ifdef stuff is for selection between a ns32k-dependent routine
   and a general version. (My advice: use the general version!).  */

static void
md_number_to_field (buf, val, field_ptr)
     register char *buf;
     register long val;
     register bit_fixS *field_ptr;
{
  register unsigned long object;
  register unsigned long mask;
  /* define ENDIAN on a ns32k machine */
#ifdef ENDIAN
  register unsigned long *mem_ptr;
#else
  register char *mem_ptr;
#endif
  if (field_ptr->fx_bit_min <= val && val <= field_ptr->fx_bit_max)
    {
#ifdef ENDIAN
      if (field_ptr->fx_bit_base)
	/* Override buf.  */
	mem_ptr = (unsigned long *) field_ptr->fx_bit_base;
      else
	mem_ptr = (unsigned long *) buf;

      mem_ptr = ((unsigned long *)
		 ((char *) mem_ptr + field_ptr->fx_bit_base_adj));
#else
      if (field_ptr->fx_bit_base)
	mem_ptr = (char *) field_ptr->fx_bit_base;
      else
	mem_ptr = buf;

      mem_ptr += field_ptr->fx_bit_base_adj;
#endif
#ifdef ENDIAN
      /* We have a nice ns32k machine with lowbyte at low-physical mem.  */
      object = *mem_ptr;	/* get some bytes */
#else /* OVE Goof! the machine is a m68k or dito */
      /* That takes more byte fiddling.  */
      object = 0;
      object |= mem_ptr[3] & 0xff;
      object <<= 8;
      object |= mem_ptr[2] & 0xff;
      object <<= 8;
      object |= mem_ptr[1] & 0xff;
      object <<= 8;
      object |= mem_ptr[0] & 0xff;
#endif
      mask = 0;
      mask |= (r_mask[field_ptr->fx_bit_offset]);
      mask |= (l_mask[field_ptr->fx_bit_offset + field_ptr->fx_bit_size]);
      object &= mask;
      val += field_ptr->fx_bit_add;
      object |= ((val << field_ptr->fx_bit_offset) & (mask ^ 0xffffffff));
#ifdef ENDIAN
      *mem_ptr = object;
#else
      mem_ptr[0] = (char) object;
      object >>= 8;
      mem_ptr[1] = (char) object;
      object >>= 8;
      mem_ptr[2] = (char) object;
      object >>= 8;
      mem_ptr[3] = (char) object;
#endif
    }
  else
    {
      as_warn (_("Bit field out of range"));
    }
}

int
md_pcrel_adjust (fragP)
     fragS *fragP;
{
  fragS *opcode_frag;
  addressT opcode_address;
  unsigned int offset;

  opcode_frag = frag_opcode_frag (fragP);
  if (opcode_frag == 0)
    return 0;

  offset = frag_opcode_offset (fragP);
  opcode_address = offset + opcode_frag->fr_address;

  return fragP->fr_address + fragP->fr_fix - opcode_address;
}

int
md_fix_pcrel_adjust (fixP)
     fixS *fixP;
{
  fragS *fragP = fixP->fx_frag;
  fragS *opcode_frag;
  addressT opcode_address;
  unsigned int offset;

  opcode_frag = fix_opcode_frag (fixP);
  if (opcode_frag == 0)
    return 0;

  offset = fix_opcode_offset (fixP);
  opcode_address = offset + opcode_frag->fr_address;

  return fixP->fx_where + fixP->fx_frag->fr_address - opcode_address;
}

/* Apply a fixS (fixup of an instruction or data that we didn't have
   enough info to complete immediately) to the data in a frag.

   On the ns32k, everything is in a different format, so we have broken
   out separate functions for each kind of thing we could be fixing.
   They all get called from here.  */

#ifdef BFD_ASSEMBLER
int
md_apply_fix (fixP, valp)
     fixS *fixP;
     valueT *valp;
#else
void
md_apply_fix (fixP, val)
     fixS *fixP;
     long val;
#endif
{
#ifdef BFD_ASSEMBLER
  long val = *valp;
#endif
  fragS *fragP = fixP->fx_frag;

  char *buf = fixP->fx_where + fixP->fx_frag->fr_literal;

  if (fix_bit_fixP (fixP))
    {				/* Bitfields to fix, sigh.  */
      md_number_to_field (buf, val, fix_bit_fixP (fixP));
    }
  else
    switch (fix_im_disp (fixP))
      {
      case 0:			/* Immediate field.  */
	md_number_to_imm (buf, val, fixP->fx_size);
	break;

      case 1:			/* Displacement field.  */
	/* Calculate offset */
	{
	  md_number_to_disp (buf,
			     (fixP->fx_pcrel ? val + md_fix_pcrel_adjust (fixP)
			      : val), fixP->fx_size);
	}
	break;

      case 2:			/* Pointer in a data object.  */
	md_number_to_chars (buf, val, fixP->fx_size);
	break;
      }
#ifdef BSD_ASSEMBLER
  return 1;
#endif
}

/* Convert a relaxed displacement to ditto in final output */

#ifndef BFD_ASSEMBLER
void
md_convert_frag (headers, sec, fragP)
     object_headers *headers;
     segT sec;
     register fragS *fragP;
#else
void
md_convert_frag (abfd, sec, fragP)
     bfd *abfd;
     segT sec;
     register fragS *fragP;
#endif
{
  long disp;
  long ext = 0;

  /* Address in gas core of the place to store the displacement.  */
  register char *buffer_address = fragP->fr_fix + fragP->fr_literal;
  /* Address in object code of the displacement.  */
  int object_address;

  fragS *opcode_frag;

  switch (fragP->fr_subtype)
    {
    case IND (BRANCH, BYTE):
      ext = 1;
      break;
    case IND (BRANCH, WORD):
      ext = 2;
      break;
    case IND (BRANCH, DOUBLE):
      ext = 4;
      break;
    }

  if (ext == 0)
    return;

  know (fragP->fr_symbol);

  object_address = fragP->fr_fix + fragP->fr_address;

  /* The displacement of the address, from current location.  */
  disp = (S_GET_VALUE (fragP->fr_symbol) + fragP->fr_offset) - object_address;
#ifdef BFD_ASSEMBLER
  disp += symbol_get_frag (fragP->fr_symbol)->fr_address;
#endif
  disp += md_pcrel_adjust (fragP);

  md_number_to_disp (buffer_address, (long) disp, (int) ext);
  fragP->fr_fix += ext;
}

/* This function returns the estimated size a variable object will occupy,
   one can say that we tries to guess the size of the objects before we
   actually know it.  */

int
md_estimate_size_before_relax (fragP, segment)
     register fragS *fragP;
     segT segment;
{
  if (fragP->fr_subtype == IND (BRANCH, UNDEF))
    {
      if (S_GET_SEGMENT (fragP->fr_symbol) != segment)
	{
	  /* We don't relax symbols defined in another segment.  The
	     thing to do is to assume the object will occupy 4 bytes.  */
	  fix_new_ns32k (fragP,
			 (int) (fragP->fr_fix),
			 4,
			 fragP->fr_symbol,
			 fragP->fr_offset,
			 1,
			 1,
			 0,
			 frag_bsr(fragP), /*sequent hack */
			 frag_opcode_frag (fragP),
			 frag_opcode_offset (fragP));
	  fragP->fr_fix += 4;
#if 0
	  fragP->fr_opcode[1] = 0xff;
#endif
	  frag_wane (fragP);
	  return 4;
	}

      /* Relaxable case.  Set up the initial guess for the variable
	 part of the frag.  */
      fragP->fr_subtype = IND (BRANCH, BYTE);
    }

  if (fragP->fr_subtype >= sizeof (md_relax_table) / sizeof (md_relax_table[0]))
    abort ();

  /* Return the size of the variable part of the frag.  */
  return md_relax_table[fragP->fr_subtype].rlx_length;
}

int md_short_jump_size = 3;
int md_long_jump_size = 5;
const int md_reloc_size = 8;	/* Size of relocation record.  */

void
md_create_short_jump (ptr, from_addr, to_addr, frag, to_symbol)
     char *ptr;
     addressT from_addr, to_addr;
     fragS *frag;
     symbolS *to_symbol;
{
  valueT offset;

  offset = to_addr - from_addr;
  md_number_to_chars (ptr, (valueT) 0xEA, 1);
  md_number_to_disp (ptr + 1, (valueT) offset, 2);
}

void
md_create_long_jump (ptr, from_addr, to_addr, frag, to_symbol)
     char *ptr;
     addressT from_addr, to_addr;
     fragS *frag;
     symbolS *to_symbol;
{
  valueT offset;

  offset = to_addr - from_addr;
  md_number_to_chars (ptr, (valueT) 0xEA, 1);
  md_number_to_disp (ptr + 1, (valueT) offset, 4);
}

CONST char *md_shortopts = "m:";

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;
     char *arg;
{
  switch (c)
    {
    case 'm':
      if (!strcmp (arg, "32032"))
	{
	  cpureg = cpureg_032;
	  mmureg = mmureg_032;
	}
      else if (!strcmp (arg, "32532"))
	{
	  cpureg = cpureg_532;
	  mmureg = mmureg_532;
	}
      else
	{
	  as_bad (_("invalid architecture option -m%s"), arg);
	  return 0;
	}
      break;

    default:
      return 0;
    }

  return 1;
}

void
md_show_usage (stream)
     FILE *stream;
{
  fprintf (stream, _("\
NS32K options:\n\
-m32032 | -m32532	select variant of NS32K architecture\n"));
}

/* Create a bit_fixS in obstack 'notes'.
   This struct is used to profile the normal fix. If the bit_fixP is a
   valid pointer (not NULL) the bit_fix data will be used to format
   the fix.  */

bit_fixS *
bit_fix_new (size, offset, min, max, add, base_type, base_adj)
     char size;			/* Length of bitfield		*/
     char offset;		/* Bit offset to bitfield	*/
     long min;			/* Signextended min for bitfield */
     long max;			/* Signextended max for bitfield */
     long add;			/* Add mask, used for huffman prefix */
     long base_type;		/* 0 or 1, if 1 it's exploded to opcode ptr */
     long base_adj;
{
  register bit_fixS *bit_fixP;

  bit_fixP = (bit_fixS *) obstack_alloc (&notes, sizeof (bit_fixS));

  bit_fixP->fx_bit_size = size;
  bit_fixP->fx_bit_offset = offset;
  bit_fixP->fx_bit_base = base_type;
  bit_fixP->fx_bit_base_adj = base_adj;
  bit_fixP->fx_bit_max = max;
  bit_fixP->fx_bit_min = min;
  bit_fixP->fx_bit_add = add;

  return (bit_fixP);
}

void
fix_new_ns32k (frag, where, size, add_symbol, offset, pcrel,
	       im_disp, bit_fixP, bsr, opcode_frag, opcode_offset)
     fragS *frag;		/* Which frag? */
     int where;			/* Where in that frag? */
     int size;			/* 1, 2  or 4 usually.  */
     symbolS *add_symbol;	/* X_add_symbol.  */
     long offset;		/* X_add_number.  */
     int pcrel;			/* TRUE if PC-relative relocation.  */
     char im_disp;		/* true if the value to write is a
				   displacement */
     bit_fixS *bit_fixP;	/* pointer at struct of bit_fix's, ignored if
				   NULL */
     char bsr;			/* sequent-linker-hack: 1 when relocobject is
				   a bsr */
     fragS *opcode_frag;
     unsigned int opcode_offset;
{
  fixS *fixP = fix_new (frag, where, size, add_symbol,
			offset, pcrel,
#ifdef BFD_ASSEMBLER
			bit_fixP ? NO_RELOC : reloc (size, pcrel, im_disp)
#else
			NO_RELOC
#endif
			);

  fix_opcode_frag (fixP) = opcode_frag;
  fix_opcode_offset (fixP) = opcode_offset;
  fix_im_disp (fixP) = im_disp;
  fix_bsr (fixP) = bsr;
  fix_bit_fixP (fixP) = bit_fixP;
}

void
fix_new_ns32k_exp (frag, where, size, exp, pcrel,
		   im_disp, bit_fixP, bsr, opcode_frag, opcode_offset)
     fragS *frag;		/* Which frag? */
     int where;			/* Where in that frag? */
     int size;			/* 1, 2  or 4 usually.  */
     expressionS *exp;		/* Expression.  */
     int pcrel;			/* TRUE if PC-relative relocation.  */
     char im_disp;		/* true if the value to write is a
				   displacement */
     bit_fixS *bit_fixP;	/* pointer at struct of bit_fix's, ignored if
				   NULL */
     char bsr;			/* sequent-linker-hack: 1 when relocobject is
				   a bsr */
     fragS *opcode_frag;
     unsigned int opcode_offset;
{
  fixS *fixP = fix_new_exp (frag, where, size, exp, pcrel,
#ifdef BFD_ASSEMBLER
			    bit_fixP ? NO_RELOC : reloc (size, pcrel, im_disp)
#else
			    NO_RELOC
#endif
			    );

  fix_opcode_frag (fixP) = opcode_frag;
  fix_opcode_offset (fixP) = opcode_offset;
  fix_im_disp (fixP) = im_disp;
  fix_bsr (fixP) = bsr;
  fix_bit_fixP (fixP) = bit_fixP;
}

/* This is TC_CONS_FIX_NEW, called by emit_expr in read.c.  */

void
cons_fix_new_ns32k (frag, where, size, exp)
     fragS *frag;		/* Which frag? */
     int where;			/* Where in that frag? */
     int size;			/* 1, 2  or 4 usually.  */
     expressionS *exp;		/* Expression.  */
{
  fix_new_ns32k_exp (frag, where, size, exp,
		     0, 2, 0, 0, 0, 0);
}

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

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

/* Round up a section size to the appropriate boundary.  */

valueT
md_section_align (segment, size)
     segT segment;
     valueT size;
{
  return size;			/* Byte alignment is fine.  */
}

/* Exactly what point is a PC-relative offset relative TO?  On the
   ns32k, they're relative to the start of the instruction.  */

long
md_pcrel_from (fixP)
     fixS *fixP;
{
  long res;
  res = fixP->fx_where + fixP->fx_frag->fr_address;
#ifdef SEQUENT_COMPATABILITY
  if (frag_bsr (fixP->fx_frag))
    res += 0x12			/* FOO Kludge alert!  */
#endif
      return res;
}

#ifdef BFD_ASSEMBLER

arelent *
tc_gen_reloc (section, fixp)
     asection *section;
     fixS *fixp;
{
  arelent *rel;
  bfd_reloc_code_real_type code;

  code = reloc (fixp->fx_size, fixp->fx_pcrel, fix_im_disp (fixp));

  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;
  if (fixp->fx_pcrel)
    rel->addend = fixp->fx_addnumber;
  else
    rel->addend = 0;

  rel->howto = bfd_reloc_type_lookup (stdoutput, code);
  if (!rel->howto)
    {
      const char *name;

      name = S_GET_NAME (fixp->fx_addsy);
      if (name == NULL)
	name = _("<unknown>");
      as_fatal (_("Cannot find relocation type for symbol %s, code %d"),
		name, (int) code);
    }

  return rel;
}
#else /* BFD_ASSEMBLER */

#ifdef OBJ_AOUT
void
cons_fix_new_ns32k (where, fixP, segment_address_in_file)
     char *where;
     struct fix *fixP;
     relax_addressT segment_address_in_file;
{
  /* In:  Length of relocation (or of address) in chars: 1, 2 or 4.
     Out: GNU LD relocation length code: 0, 1, or 2.  */

  static unsigned char nbytes_r_length[] = { 42, 0, 1, 42, 2 };
  long r_symbolnum;

  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);

  md_number_to_chars (where + 4,
		      ((long) (r_symbolnum)
		       | (long) (fixP->fx_pcrel << 24)
		       | (long) (nbytes_r_length[fixP->fx_size] << 25)
		       | (long) ((!S_IS_DEFINED (fixP->fx_addsy)) << 27)
		       | (long) (fix_bsr (fixP) << 28)
		       | (long) (fix_im_disp (fixP) << 29)),
		      4);
}

#endif /* OBJ_AOUT */
#endif /* BFD_ASSMEBLER */