source: trunk/third/gcc/config/fx80/fx80.c @ 8834

/* Subroutines for insn-output.c for Alliant FX computers.
   Copyright (C) 1989,1991 Free Software Foundation, Inc.

This file is part of GNU CC.

GNU CC 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.

GNU CC 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 GNU CC; see the file COPYING.  If not, write to
the Free Software Foundation, 59 Temple Place - Suite 330,
Boston, MA 02111-1307, USA.  */


/* Some output-actions in alliant.md need these.  */
#include <stdio.h>
#include "config.h"
#include "rtl.h"
#include "regs.h"
#include "hard-reg-set.h"
#include "real.h"
#include "insn-config.h"
#include "conditions.h"
#include "insn-flags.h"
#include "output.h"
#include "insn-attr.h"

/* Index into this array by (register number >> 3) to find the
   smallest class which contains that register.  */
enum reg_class regno_reg_class[]
  = { DATA_REGS, ADDR_REGS, FP_REGS };

static rtx find_addr_reg ();

char *
output_btst (operands, countop, dataop, insn, signpos)
     rtx *operands;
     rtx countop, dataop;
     rtx insn;
     int signpos;
{
  operands[0] = countop;
  operands[1] = dataop;

  if (GET_CODE (countop) == CONST_INT)
    {
      register int count = INTVAL (countop);
      /* If COUNT is bigger than size of storage unit in use,
         advance to the containing unit of same size.  */
      if (count > signpos)
        {
          int offset = (count & ~signpos) / 8;
          count = count & signpos;
          operands[1] = dataop = adj_offsettable_operand (dataop, offset);
        }
      if (count == signpos)
        cc_status.flags = CC_NOT_POSITIVE | CC_Z_IN_NOT_N;
      else
        cc_status.flags = CC_NOT_NEGATIVE | CC_Z_IN_NOT_N;

      /* These three statements used to use next_insns_test_no...
         but it appears that this should do the same job.  */
      if (count == 31
          && next_insn_tests_no_inequality (insn))
        return "tst%.l %1";
      if (count == 15
          && next_insn_tests_no_inequality (insn))
        return "tst%.w %1";
      if (count == 7
          && next_insn_tests_no_inequality (insn))
        return "tst%.b %1";

      cc_status.flags = CC_NOT_NEGATIVE;
    }
  return "btst %0,%1";
}

/* Return the best assembler insn template
   for moving operands[1] into operands[0] as a fullword.  */

static char *
singlemove_string (operands)
     rtx *operands;
{
  if (operands[1] != const0_rtx)
    return "mov%.l %1,%0";
  if (! ADDRESS_REG_P (operands[0]))
    return "clr%.l %0";
  return "sub%.l %0,%0";
}

/* Output assembler code to perform a doubleword move insn
   with operands OPERANDS.  */

char *
output_move_double (operands)
     rtx *operands;
{
  enum { REGOP, OFFSOP, MEMOP, PUSHOP, POPOP, CNSTOP, RNDOP } optype0, optype1;
  rtx latehalf[2];
  rtx addreg0 = 0, addreg1 = 0;

  /* First classify both operands.  */

  if (REG_P (operands[0]))
    optype0 = REGOP;
  else if (offsettable_memref_p (operands[0]))
    optype0 = OFFSOP;
  else if (GET_CODE (XEXP (operands[0], 0)) == POST_INC)
    optype0 = POPOP;
  else if (GET_CODE (XEXP (operands[0], 0)) == PRE_DEC)
    optype0 = PUSHOP;
  else if (GET_CODE (operands[0]) == MEM)
    optype0 = MEMOP;
  else
    optype0 = RNDOP;

  if (REG_P (operands[1]))
    optype1 = REGOP;
  else if (CONSTANT_P (operands[1]))
    optype1 = CNSTOP;
  else if (offsettable_memref_p (operands[1]))
    optype1 = OFFSOP;
  else if (GET_CODE (XEXP (operands[1], 0)) == POST_INC)
    optype1 = POPOP;
  else if (GET_CODE (XEXP (operands[1], 0)) == PRE_DEC)
    optype1 = PUSHOP;
  else if (GET_CODE (operands[1]) == MEM)
    optype1 = MEMOP;
  else
    optype1 = RNDOP;

  /* Check for the cases that the operand constraints are not
     supposed to allow to happen.  Abort if we get one,
     because generating code for these cases is painful.  */

  if (optype0 == RNDOP || optype1 == RNDOP)
    abort ();

  /* If one operand is decrementing and one is incrementing
     decrement the former register explicitly
     and change that operand into ordinary indexing.  */

  if (optype0 == PUSHOP && optype1 == POPOP)
    {
      operands[0] = XEXP (XEXP (operands[0], 0), 0);
      output_asm_insn ("subq%.l %#8,%0", operands);
      operands[0] = gen_rtx (MEM, DImode, operands[0]);
      optype0 = OFFSOP;
    }
  if (optype0 == POPOP && optype1 == PUSHOP)
    {
      operands[1] = XEXP (XEXP (operands[1], 0), 0);
      output_asm_insn ("subq%.l %#8,%1", operands);
      operands[1] = gen_rtx (MEM, DImode, operands[1]);
      optype1 = OFFSOP;
    }

  /* If an operand is an unoffsettable memory ref, find a register
     we can increment temporarily to make it refer to the second word.  */

  if (optype0 == MEMOP)
    addreg0 = find_addr_reg (XEXP (operands[0], 0));

  if (optype1 == MEMOP)
    addreg1 = find_addr_reg (XEXP (operands[1], 0));

  /* Ok, we can do one word at a time.
     Normally we do the low-numbered word first,
     but if either operand is autodecrementing then we
     do the high-numbered word first.

     In either case, set up in LATEHALF the operands to use
     for the high-numbered word and in some cases alter the
     operands in OPERANDS to be suitable for the low-numbered word.  */

  if (optype0 == REGOP)
    latehalf[0] = gen_rtx (REG, SImode, REGNO (operands[0]) + 1);
  else if (optype0 == OFFSOP)
    latehalf[0] = adj_offsettable_operand (operands[0], 4);
  else
    latehalf[0] = operands[0];

  if (optype1 == REGOP)
    latehalf[1] = gen_rtx (REG, SImode, REGNO (operands[1]) + 1);
  else if (optype1 == OFFSOP)
    latehalf[1] = adj_offsettable_operand (operands[1], 4);
  else if (optype1 == CNSTOP)
    {
      if (GET_CODE (operands[1]) == CONST_DOUBLE)
        split_double (operands[1], &operands[1], &latehalf[1]);
      else if (CONSTANT_P (operands[1]))
        {
          latehalf[1] = operands[1];
          operands[1] = const0_rtx;
        }
    }
  else
    latehalf[1] = operands[1];

  /* If insn is effectively movd N(sp),-(sp) then we will do the
     high word first.  We should use the adjusted operand 1 (which is N+4(sp))
     for the low word as well, to compensate for the first decrement of sp.  */
  if (optype0 == PUSHOP
      && REGNO (XEXP (XEXP (operands[0], 0), 0)) == STACK_POINTER_REGNUM
      && reg_overlap_mentioned_p (stack_pointer_rtx, operands[1]))
    operands[1] = latehalf[1];

  /* If one or both operands autodecrementing,
     do the two words, high-numbered first.  */

  /* Likewise,  the first move would clobber the source of the second one,
     do them in the other order.  This happens only for registers;
     such overlap can't happen in memory unless the user explicitly
     sets it up, and that is an undefined circumstance.  */

  if (optype0 == PUSHOP || optype1 == PUSHOP
      || (optype0 == REGOP && optype1 == REGOP
          && REGNO (operands[0]) == REGNO (latehalf[1])))
    {
      /* Make any unoffsettable addresses point at high-numbered word.  */
      if (addreg0)
        output_asm_insn ("addql %#4,%0", &addreg0);
      if (addreg1)
        output_asm_insn ("addql %#4,%0", &addreg1);

      /* Do that word.  */
      output_asm_insn (singlemove_string (latehalf), latehalf);

      /* Undo the adds we just did.  */
      if (addreg0)
        output_asm_insn ("subql %#4,%0", &addreg0);
      if (addreg1)
        output_asm_insn ("subql %#4,%0", &addreg1);

      /* Do low-numbered word.  */
      return singlemove_string (operands);
    }

  /* Normal case: do the two words, low-numbered first.  */

  output_asm_insn (singlemove_string (operands), operands);

  /* Make any unoffsettable addresses point at high-numbered word.  */
  if (addreg0)
    output_asm_insn ("addql %#4,%0", &addreg0);
  if (addreg1)
    output_asm_insn ("addql %#4,%0", &addreg1);

  /* Do that word.  */
  output_asm_insn (singlemove_string (latehalf), latehalf);

  /* Undo the adds we just did.  */
  if (addreg0)
    output_asm_insn ("subql %#4,%0", &addreg0);
  if (addreg1)
    output_asm_insn ("subql %#4,%0", &addreg1);

  return "";
}

/* Return a REG that occurs in ADDR with coefficient 1.
   ADDR can be effectively incremented by incrementing REG.  */

static rtx
find_addr_reg (addr)
     rtx addr;
{
  while (GET_CODE (addr) == PLUS)
    {
      if (GET_CODE (XEXP (addr, 0)) == REG)
        addr = XEXP (addr, 0);
      else if (GET_CODE (XEXP (addr, 1)) == REG)
        addr = XEXP (addr, 1);
      else if (CONSTANT_P (XEXP (addr, 0)))
        addr = XEXP (addr, 1);
      else if (CONSTANT_P (XEXP (addr, 1)))
        addr = XEXP (addr, 0);
      else
        abort ();
    }
  if (GET_CODE (addr) == REG)
    return addr;
  abort ();
}

int
standard_SunFPA_constant_p (x)
     rtx x;
{
  return( 0 );
}