a29k.c

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      return;

    case 'B':
      if (GET_CODE (x) == GE)
	fprintf (file, "t");
      else
	fprintf (file, "f");
      return;

    case 'J':
      /* It so happens that the RTX names for the conditions are the same as
	 the 29k's insns except for "ne", which requires "neq".  */
      fprintf (file, GET_RTX_NAME (GET_CODE (x)));
      if (GET_CODE (x) == NE)
	fprintf (file, "q");
      return;

    case 'e':
      if (optimize && flag_delayed_branch
	  && a29k_last_prologue_insn == 0 && epilogue_operand (x, VOIDmode)
	  && dbr_sequence_length () == 0)
	{
	  /* We need to output the label number of the last label in the
	     function, which is not necessarily X since there might be
	     a USE insn in between.  First go forward to the last insn, then
	     back up to a label.  */
	  while (NEXT_INSN (x) != 0)
	    x = NEXT_INSN (x);

	  while (GET_CODE (x) != CODE_LABEL)
	    x = PREV_INSN (x);

	  ASM_GENERATE_INTERNAL_LABEL (buf, "LX", CODE_LABEL_NUMBER (x));
	  assemble_name (file, buf);
	}
      else
	output_asm_label (x);
      return;

    case 'E':
      if (dbr_sequence_length ())
	;
      else if (a29k_last_prologue_insn)
	{
	  fprintf (file, "\n\t%s", a29k_last_prologue_insn);
	  a29k_last_prologue_insn = 0;
	}
      else if (optimize && flag_delayed_branch
	       && epilogue_operand (x, VOIDmode))
	{
	  fprintf (file, "\n\t%s", a29k_first_epilogue_insn);
	  a29k_first_epilogue_insn_used = 1;
	}
      else
	fprintf (file, "\n\tnop");
      return;
      
    case 'F':
      output_addr_const (file, x);
      if (dbr_sequence_length () == 0)
	{
	  /* If this doesn't have its delay slot filled, see if we need to
	     put the last insn of the prolog in it.  If not, see if this is
	     a recursive call.  If so, we can put the first insn of its
	     prolog in the delay slot.  Otherwise, write a nop.  */
	  if (a29k_last_prologue_insn)
	    {
	      fprintf (file, "\n\t%s", a29k_last_prologue_insn);
	      a29k_last_prologue_insn = 0;
	    }
	  else if (GET_CODE (x) == SYMBOL_REF
	      && ! strcmp (XSTR (x, 0), current_function_name))
	    fprintf (file, "+4\n\t%s,%d",
		     a29k_regstack_size >= 64 ? "const gr121" : "sub gr1,gr1",
		     a29k_regstack_size * 4);
	  else
	    fprintf (file, "\n\tnop");
	}
      return;

    case 'L':
      if (GET_CODE (x) == CONST_DOUBLE && GET_MODE (x) == DFmode)
	{
	  union real_extract u;

	  bcopy ((char *) &CONST_DOUBLE_LOW (x), (char *) &u, sizeof u);
	  fprintf (file, "$double1(%.20e)", u.d);
	}
      else if (GET_CODE (x) == REG)
	fprintf (file, "%s", reg_names[REGNO (x) + 1]);
      else
	output_operand_lossage ("invalid %%L value");
      return;

    case 'O':
      if (GET_CODE (x) != REG)
	output_operand_lossage ("invalid %%O value");
      fprintf (file, "%s", reg_names[REGNO (x) + 2]);
      return;

    case 'P':
      if (GET_CODE (x) != REG)
	output_operand_lossage ("invalid %%P value");
      fprintf (file, "%s", reg_names[REGNO (x) + 3]);
      return;

    case 'S':
      fprintf (file, "%d", (GET_MODE_SIZE (GET_MODE (x)) / UNITS_PER_WORD)-1);
      return;

    case 'V':
      if (GET_CODE (x) != PARALLEL)
	output_operand_lossage ("invalid %%V value");
      fprintf (file, "%d", XVECLEN (x, 0) - 2);
      return;

    case '#':
      if (dbr_sequence_length () == 0)
	{
	  if (a29k_last_prologue_insn)
	    {
	      fprintf (file, "\n\t%s", a29k_last_prologue_insn);
	      a29k_last_prologue_insn = 0;
	    }
	  else
	    fprintf (file, "\n\tnop");
	}
      return;

    case '*':
      fprintf (file, "%s", reg_names [R_TPC]);
      return;
    }

  if (GET_CODE (x) == REG)
    fprintf (file, "%s", reg_names [REGNO (x)]);

  else if (GET_CODE (x) == MEM)
    output_address (XEXP (x, 0));

  else if (GET_CODE (x) == CONST && GET_CODE (XEXP (x, 0)) == SUBREG
	   && GET_CODE (SUBREG_REG (XEXP (x, 0))) == CONST_DOUBLE)
    {
      union real_extract u;

      if (GET_MODE (SUBREG_REG (XEXP (x, 0))) == SFmode)
	fprintf (file, "$float");
      else
	fprintf (file, "$double%d", SUBREG_WORD (XEXP (x, 0)));
      bcopy ((char *) &CONST_DOUBLE_LOW (SUBREG_REG (XEXP (x, 0))),
	     (char *) &u, sizeof u);
      fprintf (file, "(%.20e)", u.d);
    }

  else if (GET_CODE (x) == CONST_DOUBLE
	   && GET_MODE_CLASS (GET_MODE (x)) == MODE_FLOAT)
    {
      union real_extract u;

      bcopy ((char *) &CONST_DOUBLE_LOW (x), (char *) &u, sizeof u);
      fprintf (file, "$%s(%.20e)",
	       GET_MODE (x) == SFmode ? "float" : "double0", u.d);
    }

  else
    output_addr_const (file, x);
}

/* This page contains routines to output function prolog and epilog code. */

/* Compute the size of the register stack, and determine if there are any
   call instructions.  */

static void
compute_regstack_size ()
{
  int i;
  rtx insn;

  /* See if we make any calls.  We need to set lr1 if so.  */
  a29k_makes_calls = 0;
  for (insn = get_insns (); insn; insn = next_insn (insn))
    if (GET_CODE (insn) == CALL_INSN
	|| (GET_CODE (insn) == INSN
	    && GET_CODE (PATTERN (insn)) == SEQUENCE
	    && GET_CODE (XVECEXP (PATTERN (insn), 0, 0)) == CALL_INSN))
      {
	a29k_makes_calls = 1;
	break;
      }

  /* Find the highest local register used.  */
  for (i = R_LR (127); i >= R_LR (0); i--)
    if (regs_ever_live[i])
      break;

  a29k_regstack_size = i - (R_LR (0) - 1);

  /* If calling routines, ensure we count lr0 & lr1.  */
  if (a29k_makes_calls && a29k_regstack_size < 2)
    a29k_regstack_size = 2;

  /* Count frame pointer and align to 8 byte boundary (even number of
     registers).  */
  a29k_regstack_size += frame_pointer_needed;
  if (a29k_regstack_size & 1) a29k_regstack_size++;
}

/*  Sets register names for incoming arguments and frame pointer.
    This can't be computed until after register allocation.  */

void
a29k_compute_reg_names ()
{
  int i;

  compute_regstack_size ();

  /* Set the names and numbers of the frame pointer and incoming argument
     registers.  */

  for (i = 0; i < FIRST_PSEUDO_REGISTER; i++)
    a29k_debug_reg_map[i] = i;

  reg_names[FRAME_POINTER_REGNUM] = reg_names[R_LR (a29k_regstack_size - 1)];
  a29k_debug_reg_map[FRAME_POINTER_REGNUM] = R_LR (a29k_regstack_size - 1);

  for (i = 0; i < 16; i++)
    {
      reg_names[R_AR (i)] = reg_names[R_LR (a29k_regstack_size + i + 2)];
      a29k_debug_reg_map[R_AR (i)] = R_LR (a29k_regstack_size + i + 2);
    }

  /* If using kernel register map, swap numbers for kernel and user
     registers.  */
  if (TARGET_KERNEL_REGISTERS)
    for (i = 0; i < 32; i++)
      {
	int tem = a29k_debug_reg_map[i];
	a29k_debug_reg_map[i] = a29k_debug_reg_map[R_KR (i)];
	a29k_debug_reg_map[R_KR (i)] = tem;
      }
}

/* Output function prolog code to file FILE.  Memory stack size is SIZE.  */

void
output_prolog (file, size)
     FILE *file;
     int size;
{
  int i;
  int arg_count = 0;
  rtx insn;
  unsigned int tag_word;

  /* See how many incoming arguments we have in registers.  */
  for (i = R_AR (0); i < R_AR (16); i++)
    if (! fixed_regs[i])
      arg_count++;

  /* The argument count includes the caller's lr0 and lr1.  */
  arg_count += 2;

  /* Compute memory stack size.  Add in number of bytes that the we should
     push and pretend the caller did and the size of outgoing arguments.
     Then round to a doubleword boundary.  */
  size += (current_function_pretend_args_size
	   + current_function_outgoing_args_size);
  size = (size + 7) & ~7;

  /* Write header words.  See if one or two word form.  */
  tag_word = (frame_pointer_needed ? 0x400000 : 0) + (arg_count << 16);

  if (size / 8 > 0xff)
    fprintf (file, "\t.word %d, 0x%0x\n", (size / 8) << 2,
	     0x800000 + tag_word);
  else
    fprintf (file, "\t.word 0x%0x\n", tag_word + ((size / 8) << 3));

  /* Define the function name.  */
  assemble_name (file, a29k_function_name);
  fprintf (file, ":\n");

  /* Push the register stack by the proper amount.  There are two possible
     ways to do this.  */
  if (a29k_regstack_size >= 256/4)
    fprintf (file, "\tconst %s,%d\n\tsub gr1,gr1,%s\n",
	     reg_names[R_TAV], a29k_regstack_size * 4, reg_names[R_TAV]);
  else if (a29k_regstack_size)
    fprintf (file, "\tsub gr1,gr1,%d\n", a29k_regstack_size * 4);

  /* Test that the registers are available.  */
  if (a29k_regstack_size)
    fprintf (file, "\tasgeu V_%sSPILL,gr1,%s\n",
	     TARGET_KERNEL_REGISTERS ? "K" : "", reg_names[R_RAB]);

  /* Set up frame pointer, if one is needed.  */
  if (frame_pointer_needed)
    fprintf (file, "\tsll %s,%s,0\n", reg_names[FRAME_POINTER_REGNUM],
	     reg_names[R_MSP]);

  /* Make room for any frame space.  There are three ways to do this.  */
  if (size >= 256)
    {
      fprintf (file, "\tconst %s,%d\n", reg_names[R_TAV], size);
      if (size >= 65536)
	fprintf (file, "\tconsth %s,%d\n", reg_names[R_TAV], size);
      if (TARGET_STACK_CHECK)
	fprintf (file, "\tcall %s,__msp_check\n", reg_names[R_TPC]);
      fprintf (file, "\tsub %s,%s,%s\n",
	       reg_names[R_MSP], reg_names[R_MSP], reg_names[R_TAV]);
    }
  else if (size)
    {
      if (TARGET_STACK_CHECK)
	fprintf (file, "\tcall %s,__msp_check\n", reg_names[R_TPC]);
      fprintf (file, "\tsub %s,%s,%d\n",
	       reg_names[R_MSP], reg_names[R_MSP], size);
    }

  /* If this routine will make calls, set lr1.  If we see an insn that
     can use a delay slot before a call or jump, save this insn for that
     slot (this condition is equivalent to seeing if we have an insn that
     needs delay slots before an insn that has a filled delay slot).  */
  a29k_last_prologue_insn = 0;
  if (a29k_makes_calls)
    {
      i = (a29k_regstack_size + arg_count) * 4;
      if (i >= 256)
	fprintf (file, "\tconst %s,%d\n\tadd lr1,gr1,%s\n",
		 reg_names[R_TAV], i, reg_names[R_TAV]);
      else
	{
	  if (optimize && flag_delayed_branch)
	    for (insn = get_insns (); insn; insn = NEXT_INSN (insn))
	      {
		if (GET_CODE (insn) == CODE_LABEL
		    || (GET_CODE (insn) == INSN
			&& GET_CODE (PATTERN (insn)) == SEQUENCE))
		  break;

		if (GET_CODE (insn) == NOTE
		    || (GET_CODE (insn) == INSN
			&& (GET_CODE (PATTERN (insn)) == USE
			    || GET_CODE (PATTERN (insn)) == CLOBBER)))
		  continue;

		if (num_delay_slots (insn) > 0)
		  {
		    a29k_last_prologue_insn = (char *) oballoc (100);
		    sprintf (a29k_last_prologue_insn, "add lr1,gr1,%d", i);
		    break;
		  }
	      }

	  if (a29k_last_prologue_insn == 0)
	    fprintf (file, "\tadd lr1,gr1,%d\n", i);
	}
    }

  /* Compute the first insn of the epilogue.  */
  a29k_first_epilogue_insn_used = 0;

  if (size == 0 && a29k_regstack_size == 0 && ! frame_pointer_needed)
    a29k_first_epilogue_insn = 0;
  else
    a29k_first_epilogue_insn = (char *) oballoc (100);

  if (frame_pointer_needed)
    sprintf (a29k_first_epilogue_insn, "sll %s,%s,0",
	     reg_names[R_MSP], reg_names[FRAME_POINTER_REGNUM]);
  else if (a29k_regstack_size)
    {
      if (a29k_regstack_size >= 256 / 4)
	sprintf (a29k_first_epilogue_insn, "const %s,%d",
		 reg_names[R_TAV], a29k_regstack_size * 4);
      else
	sprintf (a29k_first_epilogue_insn, "add gr1,gr1,%d",
		 a29k_regstack_size * 4);
    }
  else if (size)
    {
      if (size >= 256)
	sprintf (a29k_first_epilogue_insn, "const %s,%d",
		 reg_names[R_TAV], size);
      else
	sprintf (a29k_first_epilogue_insn, "add %s,%s,%d",
		 reg_names[R_MSP], reg_names[R_MSP], size);
    }
}

/* Call this after writing what might be the first instruction of the
   epilogue.  If that first insn was used in a delay slot, an intermediate
   label is written.  */

static void
check_epilogue_internal_label (file)
     FILE *file;
{
  rtx insn;

  if (! a29k_first_epilogue_insn_used)
    return;

  for (insn = get_last_insn ();
       GET_CODE (insn) != CODE_LABEL;
       insn = PREV_INSN (insn))
    ;

  ASM_OUTPUT_INTERNAL_LABEL (file, "LX", CODE_LABEL_NUMBER (insn));
  a29k_first_epilogue_insn_used = 0;
}

/* Output the epilog of the last procedure to file FILE.  SIZE is the memory
   stack size.  The register stack size is in the variable
   A29K_REGSTACK_SIZE.  */

void
output_epilog (file, size)
     FILE *file;
     int size;
{
  rtx insn;
  int locals_unavailable = 0;	/* True until after first insn
				   after gr1 update. */

  /* If we hit a BARRIER before a real insn or CODE_LABEL, we don't
     need to do anything because we are never jumped to.  */
  insn = get_last_insn ();
  if (GET_CODE (insn) == NOTE)
    insn = prev_nonnote_insn (insn);

  if (insn && GET_CODE (insn) == BARRIER)
    return;

  /* If a frame pointer was needed we must restore the memory stack pointer
     before adjusting the register stack.  */
  if (frame_pointer_needed)
    {
      fprintf (file, "\tsll %s,%s,0\n",
	       reg_names[R_MSP], reg_names[FRAME_POINTER_REGNUM]);
      check_epilogue_internal_label (file);
    }

  /* Restore the register stack.  There are two ways to do this.  */
  if (a29k_regstack_size)
    {
      if (a29k_regstack_size >= 256/4)
	{
	  fprintf (file, "\tconst %s,%d\n",
		   reg_names[R_TAV], a29k_regstack_size * 4);
	  check_epilogue_internal_label (file);
	  fprintf (file, "\tadd gr1,gr1,%s\n", reg_names[R_TAV]);
	}
      else
	{
	  fprintf (file, "\tadd gr1,gr1,%d\n", a29k_regstack_size * 4);
	  check_epilogue_internal_label (file);
	}
      locals_unavailable = 1;
    }

  /* Restore the memory stack pointer if there is no frame pointer.
     Adjust the size to include any pretend arguments and pushed
     arguments and round to doubleword boundary.  */
  size += (current_function_pretend_args_size
	   + current_function_outgoing_args_size);
  size = (size + 7) & ~7;

  if (size && ! frame_pointer_needed)
    {
      if (size >= 256)
	{
	  fprintf (file, "\tconst %s,%d\n", reg_names[R_TAV], size);
	  check_epilogue_internal_label (file);
	  locals_unavailable = 0;
	  if (size >= 65536)
	    fprintf (file, "\tconsth %s,%d\n", reg_names[R_TAV], size);
	  fprintf (file, "\tadd %s,%s,%s\n",
		   reg_names[R_MSP], reg_names[R_MSP], reg_names[R_TAV]);
	}
      else
	{
	  fprintf (file, "\tadd %s,%s,%d\n",
		   reg_names[R_MSP], reg_names[R_MSP], size);
	  check_epilogue_internal_label (file);
	  locals_unavailable = 0;
	}
    }

  if (locals_unavailable)
    {
      /* If we have an insn for this delay slot, write it.  */
      if (current_function_epilogue_delay_list)
	final_scan_insn (XEXP (current_function_epilogue_delay_list, 0),
			 file, 1, -2, 1);
      else
	fprintf (file, "\tnop\n");
    }

  fprintf (file, "\tjmpi lr0\n");
  if (a29k_regstack_size)
    fprintf (file, "\tasleu V_%sFILL,lr1,%s\n",
	     TARGET_KERNEL_REGISTERS ? "K" : "", reg_names[R_RFB]);
  else if (current_function_epilogue_delay_list)
    final_scan_insn (XEXP (current_function_epilogue_delay_list, 0),
		     file, 1, -2, 1);
  else
    fprintf (file, "\tnop\n");
}