romp.c

早期freebsd实现

  noperands = 1 + (op1 != 0) + (op2 != 0);

  /* Compute hash code for entire expression and see if operation block
     already exists.  */
  hash = ((int) code << 13) + (hash0 << 2) + (hash1 << 1) + hash2;

  hash %= FP_HASH_SIZE;
  for (fpop = fp_hash_table[hash], last_fpop = 0;
       fpop;
       last_fpop = fpop, fpop = fpop->next_same_hash)
    if (fpop->opcode == code && noperands == fpop->noperands
	&& (op0 == 0 || rtx_equal_p (op0, fpop->ops[0]))
	&& (op1 == 0 || rtx_equal_p (op1, fpop->ops[1]))
	&& (op2 == 0 || rtx_equal_p (op2, fpop->ops[2])))
      goto win;

  /* We have never seen this operation before.  */
  fpop = (struct fp_op *) oballoc (sizeof (struct fp_op));
  fpop->mem_offset = data_offset;
  fpop->opcode = code;
  fpop->noperands = noperands;
  fpop->ops[0] = op0;
  fpop->ops[1] = op1;
  fpop->ops[2] = op2;

  /* Compute the size using the rules in Appendix A of the RT Linkage
     Convention (4.3/RT-PSD:5) manual.  These rules are a bit ambiguous,
     but if we guess wrong, it will effect only efficiency, not correctness. */

  /* Size = 24 + 32 for each non-fp (or fr7) */
  size = 24;
  if (op0 && (GET_CODE (op0) != REG
	      || ! FP_REGNO_P (REGNO (op0)) || REGNO (op0) == 23))
    size += 32;

  if (op1 && (GET_CODE (op1) != REG
	      || ! FP_REGNO_P (REGNO (op1)) || REGNO (op1) == 23))
    size += 32;

  if (op2 && (GET_CODE (op2) != REG
	      || ! FP_REGNO_P (REGNO (op2)) || REGNO (op2) == 23))
    size += 32;

  /* Size + 12 for each conversion.  First get operation mode.  */
  if ((op0 && GET_MODE (op0) == DFmode)
      || (op1 && GET_MODE (op1) == DFmode)
      || (op2 && GET_MODE (op2) == DFmode))
    opmode = DFmode;
  else
    opmode = SFmode;

  if (op0 && GET_MODE (op0) != opmode)
    size += 12;
  if (op1 && GET_MODE (op1) != opmode)
    size += 12;
  if (op2 && GET_MODE (op2) != opmode)
    size += 12;

  /* 12 more if first and third operand types not the same. */
  if (op2 && GET_MODE (op0) != GET_MODE (op2))
    size += 12;

  /* CMP and CMPT need additional.  Also, compute size of save/restore here. */
  if (code == EQ)
    size += 32;
  else if (code == GE)
    size += 64;
  else if (code == USE || code == CLOBBER)
    {
      /* 34 + 24 for each additional register plus 8 if fr7 saved.  (We
         call it 36 because we need to keep the block length a multiple
	 of four.  */
      size = 36 - 24;
      for (i = 0; i <= 7; i++)
	if (INTVAL (op0) & (1 << (7-i)))
	  size += 24 + 8 * (i == 7);
    }

  /* We provide no general-purpose scratch registers.  */
  size +=16;

  /* No floating-point scratch registers are provided.  Compute extra
     length due to this.  This logic is that shown in the referenced
     appendix.  */

  i = 0;
  if (op0 && GET_CODE (op0) == REG && FP_REGNO_P (REGNO (op0)))
    i++;
  if (op1 && GET_CODE (op1) == REG && FP_REGNO_P (REGNO (op1)))
    i++;
  if (op2 && GET_CODE (op2) == REG && FP_REGNO_P (REGNO (op2)))
    i++;

  if ((op0 == 0 || GET_CODE (op0) != REG || REGNO(op0) != 17)
      && (op1 == 0 || GET_CODE (op1) != REG || REGNO(op1) != 17)
      && (op2 == 0 || GET_CODE (op2) != REG || REGNO(op2) != 17))
    fr0_avail = 1;

  if (dyadic)
    {
      if (i == 0)
	size += fr0_avail ? 64 : 112;
      else if (fpop->noperands == 2 && i == 1)
	size += fr0_avail ? 0 : 64;
      else if (fpop->noperands == 3)
	{
	  if (GET_CODE (op0) == REG && FP_REGNO_P (REGNO (op0))
	      && GET_CODE (op2) == REG && FP_REGNO_P (REGNO (op2)))
	    {
	      if (REGNO (op0) == REGNO (op2))
#if 1
		/* This triggers a bug on the RT. */
		abort ();
#else
		size += fr0_avail ? 0 : 64;
#endif
	    }
	  else
	    {
	      i = 0;
	      if (GET_CODE (op0) == REG && FP_REGNO_P (REGNO (op0)))
		i++;
	      if (GET_CODE (op2) == REG && FP_REGNO_P (REGNO (op2)))
		i++;
	      if (i == 0)
		size += fr0_avail ? 64 : 112;
	      else if (i == 1)
		size += fr0_avail ? 0 : 64;
	    }
	}
    }
  else if (code != USE && code != CLOBBER
	   && (GET_CODE (op0) != REG || ! FP_REGNO_P (REGNO (op0))))
    size += 64;
    
  if (! TARGET_FULL_FP_BLOCKS)
    {
      /* If we are not to pad the blocks, just compute its actual length.  */
      size = 12;	/* Header + opcode */
      if (code == USE || code == CLOBBER)
        size += 2;
      else
        {
	  if (op0) size += 2;
	  if (op1) size += 2;
	  if (op2) size += 2;
	}

      /* If in the middle of a word, round.  */
      if (size % UNITS_PER_WORD)
	size += 2;
	
      /* Handle any immediates.  */
      if (code != USE && code != CLOBBER && op0 && GET_CODE (op0) != REG)
        size += 4;
      if (op1 && GET_CODE (op1) != REG)
        size += 4;
      if (op2 && GET_CODE (op2) != REG)
        size += 4;

      if (code != USE && code != CLOBBER && 
	  op0 && GET_CODE (op0) == CONST_DOUBLE && GET_MODE (op0) == DFmode)
        size += 4;
      if (op1 && GET_CODE (op1) == CONST_DOUBLE && GET_MODE (op1) == DFmode)
        size += 4;
      if (op2 && GET_CODE (op2) == CONST_DOUBLE && GET_MODE (op2) == DFmode)
        size += 4;
    }

  /* Done with size computation!  Chain this in. */
  fpop->size = size;
  data_offset += size / UNITS_PER_WORD;
  fpop->next_in_mem = 0;
  fpop->next_same_hash = 0;

  if (last_fpop_in_mem)
    last_fpop_in_mem->next_in_mem = fpop;
  else
    first_fpop = fpop;
  last_fpop_in_mem = fpop;

  if (last_fpop)
    last_fpop->next_same_hash = fpop;
  else
    fp_hash_table[hash] = fpop;

win:
  /* FPOP describes the operation to be performed.  Return a string to branch
     to it.  */
  if (fpop->mem_offset < 32768 / UNITS_PER_WORD)
    sprintf (outbuf, "cal r15,%d(r14)\n\tbalr%s r15,r15",
	     fpop->mem_offset * UNITS_PER_WORD,
	     dbr_sequence_length () ? "x" : "");
  else
    sprintf (outbuf, "get r15,$L%dF%d\n\tbalr%s r15,r15",
	     subr_number, fpop->mem_offset * UNITS_PER_WORD,
	     dbr_sequence_length () ? "x" : "");
  return outbuf;
}

/* If necessary, output a floating-point operation to save or restore all
   floating-point registers.

   file is the file to write the operation to, CODE is USE for save, CLOBBER
   for restore, and ADDR is the address of the same area, as RTL.  */

static void
output_loadsave_fpregs (file, code, addr)
     FILE *file;
     enum rtx_code code;
     rtx addr;
{
  register int i;
  register int mask = 0;

  for (i = 2 + (TARGET_FP_REGS != 0); i <= 7; i++)
    if (regs_ever_live[i + 17])
      mask |= 1 << (7 - i);

  if (mask)
    fprintf (file, "\t%s\n",
	     output_fpop (code, gen_rtx (CONST_INT, VOIDmode, mask),
				gen_rtx (MEM, Pmode, addr),
				0, const0_rtx));

}

/* Output any floating-point operations at the end of the routine.  */

static void
output_fpops (file)
     FILE *file;
{
  register struct fp_op *fpop;
  register int size_so_far;
  register int i;
  rtx immed[3];

  if (first_fpop == 0)
    return;

  data_section ();

  ASM_OUTPUT_ALIGN (file, 2);

  for (fpop = first_fpop; fpop; fpop = fpop->next_in_mem)
    {
      if (fpop->mem_offset < 32768 / UNITS_PER_WORD)
	fprintf (file, "# data area offset = %d\n",
		 fpop->mem_offset * UNITS_PER_WORD);
      else
	fprintf (file, "L%dF%d:\n",
		 subr_number, fpop->mem_offset * UNITS_PER_WORD);

      fprintf (file, "\tcas r0,r15,r0\n");
      fprintf (file, "\t.long FPGLUE\n");
      switch (fpop->opcode)
	{
	case USE:
	  fprintf (file, "\t.byte 0x1d\t# STOREM\n");
	  break;
	case CLOBBER:
	  fprintf (file, "\t.byte 0x0f\t# LOADM\n");
	  break;
	case ABS:
	  fprintf (file, "\t.byte 0x00\t# ABS\n");
	  break;
	case PLUS:
	  fprintf (file, "\t.byte 0x02\t# ADD\n");
	  break;
	case EQ:
	  fprintf (file, "\t.byte 0x07\t# CMP\n");
	  break;
	case GE:
	  fprintf (file, "\t.byte 0x08\t# CMPT\n");
	  break;
	case DIV:
	  fprintf (file, "\t.byte 0x0c\t# DIV\n");
	  break;
	case SET:
	  fprintf (file, "\t.byte 0x14\t# MOVE\n");
	  break;
	case MULT:
	  fprintf (file, "\t.byte 0x15\t# MUL\n");
	  break;
	case NEG:
	  fprintf (file, "\t.byte 0x16\t# NEG\n");
	  break;
	case SQRT:
	  fprintf (file, "\t.byte 0x1c\t# SQRT\n");
	  break;
	case MINUS:
	  fprintf (file, "\t.byte 0x1e\t# SUB\n");
	  break;
	default:
	  abort ();
	}

      fprintf (file, "\t.byte %d\n", fpop->noperands);
      fprintf (file, "\t.short 0x8001\n");
      
      if ((fpop->ops[0] == 0
	   || GET_CODE (fpop->ops[0]) != REG || REGNO(fpop->ops[0]) != 17)
	  && (fpop->ops[1] == 0 || GET_CODE (fpop->ops[1]) != REG
	      || REGNO(fpop->ops[1]) != 17)
	  && (fpop->ops[2] == 0 || GET_CODE (fpop->ops[2]) != REG
	      || REGNO(fpop->ops[2]) != 17))
	fprintf (file, "\t.byte %d, 0x80\n", fpop->size);
      else
	fprintf (file, "\t.byte %d, 0\n", fpop->size);
      size_so_far = 12;
      for (i = 0; i < fpop->noperands; i++)
	{
	  register int type;
	  register int opbyte;
	  register char *desc0;
	  char desc1[50];

	  immed[i] = 0;
	  switch (GET_MODE (fpop->ops[i]))
	    {
	    case SImode:
	    case VOIDmode:
	      desc0 = "int";
	      type = 0;
	      break;
	    case SFmode:
	      desc0 = "float";
	      type = 2;
	      break;
	    case DFmode:
	      desc0 = "double";
	      type = 3;
	      break;
	    default:
	      abort ();
	    }

	  switch (GET_CODE (fpop->ops[i]))
	    {
	    case REG:
	      strcpy(desc1, reg_names[REGNO (fpop->ops[i])]);
	      if (FP_REGNO_P (REGNO (fpop->ops[i])))
		{
		  type += 0x10;
		  opbyte = REGNO (fpop->ops[i]) - 17;
		}
	      else
		{
		  type += 0x00;
		  opbyte = REGNO (fpop->ops[i]);
		  if (type == 3)
		    opbyte = (opbyte << 4) + opbyte + 1;
		}
	      break;

	    case MEM:
	      type += 0x30;
	      if (GET_CODE (XEXP (fpop->ops[i], 0)) == PLUS)
		{
		  immed[i] = XEXP (XEXP (fpop->ops[i], 0), 1);
		  opbyte = REGNO (XEXP (XEXP (fpop->ops[i], 0), 0));
		  if (GET_CODE (immed[i]) == CONST_INT)
		    sprintf (desc1, "%d(%s)", INTVAL (immed[i]),
			     reg_names[opbyte]);
		  else
		    sprintf (desc1, "<memory> (%s)", reg_names[opbyte]);
		}
	      else if (GET_CODE (XEXP (fpop->ops[i], 0)) == REG)
		{
		  opbyte = REGNO (XEXP (fpop->ops[i], 0));
		  immed[i] = const0_rtx;
 		  sprintf (desc1, "(%s)", reg_names[opbyte]);
		}
	      else
		{
		  immed[i] = XEXP (fpop->ops[i], 0);
		  opbyte = 0;
		  sprintf(desc1, "<memory>");
		}
	      break;

	    case CONST_INT:
	    case CONST_DOUBLE:
	    case CONST:
	    case SYMBOL_REF:
	    case LABEL_REF:
	      type += 0x20;
	      opbyte = 0;
	      immed[i] = fpop->ops[i];
	      desc1[0] = '$';
	      desc1[1] = '\0';
	      break;

	    default:
	      abort ();
	    }

	  /* Save/restore is special.  */
	  if (i == 0 && (fpop->opcode == USE || fpop->opcode == CLOBBER))
	    type = 0xff, opbyte = INTVAL (fpop->ops[0]), immed[i] = 0;

	  fprintf (file, "\t.byte 0x%x,0x%x # (%s) %s\n",
		   type, opbyte, desc0, desc1);

	  size_so_far += 2;
	}

      /* If in the middle of a word, round.  */
      if (size_so_far % UNITS_PER_WORD)
	{
	  fprintf (file, "\t.space 2\n");
	  size_so_far += 2;
	}

      for (i = 0; i < fpop->noperands; i++)
	if (immed[i])
	  switch (GET_MODE (immed[i]))
	    {
	    case SImode:
	    case VOIDmode:
	      size_so_far += 4;
	      fprintf (file, "\t.long ");
	      output_addr_const (file, immed[i]);
	      fprintf (file, "\n");
	      break;

	    case DFmode:
	      size_so_far += 4;
	    case SFmode:
	      size_so_far += 4;
	      if (GET_CODE (immed[i]) == CONST_DOUBLE)
		{
		  union real_extract u;

		  bcopy (&CONST_DOUBLE_LOW (immed[i]), &u, sizeof u);
		  if (GET_MODE (immed[i]) == DFmode)
		    ASM_OUTPUT_DOUBLE (file, u.d);
		  else
		    ASM_OUTPUT_FLOAT (file, u.d);
		}
	      else
		abort ();
	      break;

	    default:
	      abort ();
	    }
	
      if (size_so_far != fpop->size)
        {
          if (TARGET_FULL_FP_BLOCKS)
	    fprintf (file, "\t.space %d\n", fpop->size - size_so_far);
	  else
	    abort ();
	}
    }

  /* Update for next subroutine.  */
  subr_number++;
  text_section ();
}

 /* Initialize floating-point operation table.  */

static void
init_fpops()
{
  register int i;

  first_fpop = last_fpop_in_mem = 0;
  for (i = 0; i < FP_HASH_SIZE; i++)
    fp_hash_table[i] = 0;
}