tc-w65.c

基于4个mips核的noc设计

  for (; opcode->code == ocode; opcode++)
    {
      if (opcode->amode == amode)
	return opcode;
    }
  return 0;
}

int
check (operand, low, high)
     expressionS *operand;
     int low;
     int high;
{
  if (operand->X_op != O_constant
      || operand->X_add_number < low
      || operand->X_add_number > high)
    {
      as_bad ("operand must be absolute in range %d..%d", low, high);
    }
  return operand->X_add_number;
}

static int log2[] = { 0, 0, 1, 0, 2 };

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

static void
build_Mytes (opcode)
     struct opinfo *opcode;
{
  int size;
  int type;
  int pcrel;
  char *output;

  if (opcode->amode == ADDR_IMPLIED)
    {
      output = frag_more (1);
    }
  else if (opcode->amode == ADDR_PC_REL)
    {
      int type;

      /* This is a relaxable insn, so we do some special handling.  */
      type = opcode->val == OP_BRA ? UNCOND_BRANCH : COND_BRANCH;
      output = frag_var (rs_machine_dependent,
			 md_relax_table[C (type, WORD_DISP)].rlx_length,
			 md_relax_table[C (type, BYTE_DISP)].rlx_length,
			 C (type, UNDEF_BYTE_DISP),
			 immediate.X_add_symbol,
			 immediate.X_add_number,
			 0);
    }
  else
    {
      switch (opcode->amode)
	{
	  GETINFO (size, type, pcrel);
	}

      /* If something special was done in the expression modify the
	 reloc type.  */
      if (tc_cons_reloc)
	type = tc_cons_reloc;

      /* 1 byte for the opcode + the bytes for the addrmode.  */
      output = frag_more (size + 1);

      if (opcode->amode == ADDR_BLOCK_MOVE)
	{
	  /* Two relocs for this one.  */
	  fix_new_exp (frag_now,
		       output + 1 - frag_now->fr_literal,
		       1,
		       &immediate,
		       0,
		       R_W65_ABS8S16);

	  fix_new_exp (frag_now,
		       output + 2 - frag_now->fr_literal,
		       1,
		       &immediate1,
		       0,
		       R_W65_ABS8S16);
	}
      else if (type >= 0
	       && opcode->amode != ADDR_IMPLIED
	       && opcode->amode != ADDR_ACC
	       && opcode->amode != ADDR_STACK)
	{
	  fix_new_exp (frag_now,
		       output + 1 - frag_now->fr_literal,
		       size,
		       &immediate,
		       pcrel,
		       type);
	}
    }
  output[0] = opcode->val;
}

/* 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 (str)
     char *str;
{
  unsigned char *op_start;
  unsigned char *op_end;
  struct opinfo *opcode;
  char name[20];
  int nlen = 0;
  char *p;

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

  /* all opcodes are three letters */
  name[0] = str[0];
  name[1] = str[1];
  name[2] = str[2];
  name[3] = 0;

  tc_cons_reloc = 0;
  str += 3;
  opcode = (struct opinfo *) hash_find (opcode_hash_control, name);

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

  if (opcode->amode != ADDR_IMPLIED
      && opcode->amode != ADDR_STACK)
    {
      get_operands (opcode, str);
      opcode = get_specific (opcode);
    }

  if (opcode == 0)
    {
      /* Couldn't find an opcode which matched the operands.  */

      char *where = frag_more (1);

      where[0] = 0x0;
      where[1] = 0x0;
      as_bad (_("invalid operands for opcode"));
      return;
    }

  build_Mytes (opcode);
}

void
tc_crawl_symbol_chain (headers)
     object_headers *headers;
{
  printf (_("call to tc_crawl_symbol_chain \n"));
}

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

void
tc_headers_hook (headers)
     object_headers *headers;
{
  printf (_("call to tc_headers_hook \n"));
}

/* 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;
  char *atof_ieee ();

  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_NTOF()");
    }
  t = atof_ieee (input_line_pointer, type, words);
  if (t)
    input_line_pointer = t;

  *sizeP = prec * sizeof (LITTLENUM_TYPE);
  for (wordP = words + prec - 1; prec--;)
    {
      md_number_to_chars (litP, (valueT) (*wordP--), sizeof (LITTLENUM_TYPE));
      litP += sizeof (LITTLENUM_TYPE);
    }
  return 0;
}

int
md_parse_option (c, a)
     int c;
     char *a;
{
  return 1;
}

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

/* Called after relaxing, change the frags so they know how big they
   are.  */

void
md_convert_frag (headers, seg, fragP)
     object_headers *headers;
     segT seg;
     fragS *fragP;
{
  int disp_size = 0;
  int inst_size = 0;
  unsigned char *buffer =
    (unsigned char *) (fragP->fr_fix + fragP->fr_literal);

  switch (fragP->fr_subtype)
    {
    case C (COND_BRANCH, BYTE_DISP):
    case C (UNCOND_BRANCH, BYTE_DISP):
      disp_size = 1;
      inst_size = 1;
      break;

      /* Conditional branches to a known 16 bit displacement.  */
    case C (COND_BRANCH, WORD_DISP):
      switch (buffer[0])
	{
	case OP_BCC:
	case OP_BCS:
	case OP_BEQ:
	case OP_BMI:
	case OP_BNE:
	case OP_BPL:
	case OP_BVS:
	case OP_BVC:
	  /* Invert the sense of the test */
	  buffer[0] ^= 0x20;
	  buffer[1] = 3;	/* Jump over following brl */
	  buffer[2] = OP_BRL;
	  buffer[3] = 0;
	  buffer[4] = 0;
	  disp_size = 2;
	  inst_size = 3;
	  break;
	default:
	  abort ();
	}
      break;
    case C (UNCOND_BRANCH, WORD_DISP):
      /* Unconditional branches to a known 16 bit displacement.  */

      switch (buffer[0])
	{
	case OP_BRA:
	  buffer[0] = OP_BRL;
	  disp_size = 2;
	  inst_size = 1;
	  break;
	default:
	  abort ();
	}
      break;
      /* Got to create a branch over a reloc here.  */
    case C (COND_BRANCH, UNDEF_WORD_DISP):
      buffer[0] ^= 0x20;	/* invert test */
      buffer[1] = 3;
      buffer[2] = OP_BRL;
      buffer[3] = 0;
      buffer[4] = 0;
      fix_new (fragP,
	       fragP->fr_fix + 3,
	       4,
	       fragP->fr_symbol,
	       fragP->fr_offset,
	       0,
	       R_W65_PCR16);

      fragP->fr_fix += disp_size + inst_size;
      fragP->fr_var = 0;
      break;
    case C (UNCOND_BRANCH, UNDEF_WORD_DISP):
      buffer[0] = OP_BRL;
      buffer[1] = 0;
      buffer[2] = 0;
      fix_new (fragP,
	       fragP->fr_fix + 1,
	       4,
	       fragP->fr_symbol,
	       fragP->fr_offset,
	       0,
	       R_W65_PCR16);

      fragP->fr_fix += disp_size + inst_size;
      fragP->fr_var = 0;
      break;
    default:
      abort ();
    }
  if (inst_size)
    {
      /* Get the address of the end of the instruction.  */
      int next_inst = (fragP->fr_fix + fragP->fr_address
		       + disp_size + inst_size);
      int targ_addr = (S_GET_VALUE (fragP->fr_symbol) +
		       fragP->fr_offset);
      int disp = targ_addr - next_inst;

      md_number_to_chars (buffer + inst_size, disp, disp_size);
      fragP->fr_fix += disp_size + inst_size;
      fragP->fr_var = 0;
    }
}

valueT
md_section_align (seg, size)
     segT seg;
     valueT size;
{
  return ((size + (1 << section_alignment[(int) seg]) - 1)
	  & (-1 << section_alignment[(int) seg]));
}

void
md_apply_fix (fixP, val)
     fixS *fixP;
     long val;
{
  char *buf = fixP->fx_where + fixP->fx_frag->fr_literal;
  int addr = fixP->fx_frag->fr_address + fixP->fx_where;

  if (fixP->fx_r_type == 0)
    {
      if (fixP->fx_size == 1)
	fixP->fx_r_type = R_W65_ABS8;
      else
	fixP->fx_r_type = R_W65_ABS16;
    }

  switch (fixP->fx_r_type)
    {
    case R_W65_ABS8S16:
      val >>= 8;
    case R_W65_ABS8S8:
      val >>= 8;
    case R_W65_ABS8:
      *buf++ = val;
      break;
    case R_W65_ABS16S16:
      val >>= 8;
    case R_W65_ABS16S8:
      val >>= 8;
    case R_W65_ABS16:
      *buf++ = val >> 0;
      *buf++ = val >> 8;
      break;
    case R_W65_ABS24:
      *buf++ = val >> 0;
      *buf++ = val >> 8;
      *buf++ = val >> 16;
      break;
    case R_W65_PCR8:
      *buf++ = val - addr - 1;
      break;
    case R_W65_PCR16:
      val = val - addr - 1;
      *buf++ = val;
      *buf++ = val >> 8;
      break;
    case R_W65_DP:
      *buf++ = val;
      break;

    default:
      abort ();
    }
}

/* Put number into target byte order */

void
md_number_to_chars (ptr, use, nbytes)
     char *ptr;
     valueT use;
     int nbytes;
{
  number_to_chars_littleendian (ptr, use, nbytes);
}

long
md_pcrel_from (fixP)
     fixS *fixP;
{
  int gap = fixP->fx_size + fixP->fx_where + fixP->fx_frag->fr_address - 1;
  return gap;
}

void
tc_coff_symbol_emit_hook (x)
     symbolS *x;
{
}

short
tc_coff_fix2rtype (fix_ptr)
     fixS *fix_ptr;
{
  return fix_ptr->fx_r_type;
}

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 == RELOC_32)
    {
      /* cons likes to create reloc32's whatever the size of the reloc..
       */
      switch (fix_ptr->fx_size)
	{
	case 2:
	  intr->r_type = R_IMM16;
	  break;
	case 1:
	  intr->r_type = R_IMM8;
	  break;
	default:
	  abort ();
	}
    }
  else
    {
      if (fix_ptr->fx_size == 4)
	intr->r_type = R_W65_ABS24;
      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;

  /* Turn the segment of the symbol into an offset.  */
  if (symbol_ptr)
    {
      symbolS *dot;

      dot = segment_info[S_GET_SEGMENT (symbol_ptr)].dot;
      if (dot)
	{
	  intr->r_offset += S_GET_VALUE (symbol_ptr);
	  intr->r_symndx = dot->sy_number;
	}
      else
	{
	  intr->r_symndx = symbol_ptr->sy_number;
	}
    }
  else
    {
      intr->r_symndx = -1;
    }
}

int
tc_coff_sizemachdep (frag)
     fragS *frag;
{
  return md_relax_table[frag->fr_subtype].rlx_length;
}

/* Called just before address relaxation, return the length by which a
   fragment must grow to reach it's destination.  */

int
md_estimate_size_before_relax (fragP, segment_type)
     register fragS *fragP;
     register segT segment_type;
{
  int what;

  switch (fragP->fr_subtype)
    {
    default:
      abort ();

    case C (COND_BRANCH, UNDEF_BYTE_DISP):
    case C (UNCOND_BRANCH, UNDEF_BYTE_DISP):
      what = GET_WHAT (fragP->fr_subtype);
      /* Used to be a branch to somewhere which was unknown.  */
      if (S_GET_SEGMENT (fragP->fr_symbol) == segment_type)
	{
	  /* Got a symbol and it's defined in this segment, become byte
	     sized - maybe it will fix up.  */
	  fragP->fr_subtype = C (what, BYTE_DISP);
	}
      else
	{
	  /* Its got a segment, but its not ours, so it will always be
             long.  */
	  fragP->fr_subtype = C (what, UNDEF_WORD_DISP);
	}
      break;

    case C (COND_BRANCH, BYTE_DISP):
    case C (COND_BRANCH, WORD_DISP):
    case C (COND_BRANCH, UNDEF_WORD_DISP):
    case C (UNCOND_BRANCH, BYTE_DISP):
    case C (UNCOND_BRANCH, WORD_DISP):
    case C (UNCOND_BRANCH, UNDEF_WORD_DISP):
      /* When relaxing a section for the second time, we don't need to
	 do anything besides return the current size.  */
      break;
    }

  fragP->fr_var = md_relax_table[fragP->fr_subtype].rlx_length;
  return fragP->fr_var;
}

CONST char *md_shortopts = "";
struct option md_longopts[] = {
#define OPTION_RELAX (OPTION_MD_BASE)
  {NULL, no_argument, NULL, 0}
};

void
md_show_usage (stream)
     FILE *stream;
{
}

size_t md_longopts_size = sizeof (md_longopts);