gcc/config/spur/spur.c

/* Subroutines for insn-output.c for SPUR.  Adapted from routines for
   the Motorola 68000 family.
   Copyright (C) 1988, 1991, 1997 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.  */

#include "config.h"
#include <stdio.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"

static rtx find_addr_reg ();

char *
output_compare (operands, opcode, exchange_opcode, 
		neg_opcode, neg_exchange_opcode)
     rtx *operands;
     char *opcode;
     char *exchange_opcode;
     char *neg_opcode;
     char *neg_exchange_opcode;
{
  static char buf[100];
  operands[2] = operands[0];
  if (GET_CODE (cc_prev_status.value1) == CONST_INT)
    {
      operands[1] = cc_prev_status.value1;
      operands[0] = cc_prev_status.value2;
      opcode = exchange_opcode, neg_opcode = neg_exchange_opcode;
    }
  else
    {
      operands[0] = cc_prev_status.value1;
      operands[1] = cc_prev_status.value2;
    }
  if (TARGET_LONG_JUMPS)
    sprintf (buf,
	     "cmp_br_delayed %s,%%0,%%1,1f\n\tnop\n\tjump %%l2\n\tnop\n1:",
	     neg_opcode);
  else 
    sprintf (buf, "cmp_br_delayed %s,%%0,%%1,%%l2\n\tnop", opcode);
  return buf;
}

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

static char *
singlemove_string (operands)
     rtx *operands;
{
  if (GET_CODE (operands[0]) == MEM)
    return "st_32 %r1,%0";
  if (GET_CODE (operands[1]) == MEM)
    return "ld_32 %0,%1\n\tnop";
  if (GET_CODE (operands[1]) == REG)
    return "add_nt %0,%1,$0";
  return "add_nt %0,r0,%1";
}

/* 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 (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 (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 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)
	{
	  latehalf[1] = GEN_INT (CONST_DOUBLE_HIGH (operands[1]));
	  operands[1] = GEN_INT (CONST_DOUBLE_LOW (operands[1]));
	}
      else if (CONSTANT_P (operands[1]))
	latehalf[1] = const0_rtx;
    }
  else
    latehalf[1] = operands[1];

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

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

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

      /* 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 ("add_nt %0,%0,$4", &addreg0);
  if (addreg1)
    output_asm_insn ("add_nt %0,%0,$4", &addreg1);

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

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

  return "";
}

static char *
output_fp_move_double (operands)
     rtx *operands;
{
  if (FP_REG_P (operands[0]))
    {
      if (FP_REG_P (operands[1]))
	return "fmov %0,%1";
      if (GET_CODE (operands[1]) == REG)
	{
	  rtx xoperands[2];
	  int offset = - get_frame_size () - 8;
	  xoperands[1] = gen_rtx (REG, SImode, REGNO (operands[1]) + 1);
	  xoperands[0] = GEN_INT (offset + 4);
	  output_asm_insn ("st_32 %1,r25,%0", xoperands);
	  xoperands[1] = operands[1];
	  xoperands[0] = GEN_INT (offset);
	  output_asm_insn ("st_32 %1,r25,%0", xoperands);
	  xoperands[1] = operands[0];
	  output_asm_insn ("ld_dbl %1,r25,%0\n\tnop", xoperands);
	  return "";
	}
      return "ld_dbl %0,%1\n\tnop";
    }
  else if (FP_REG_P (operands[1]))
    {
      if (GET_CODE (operands[0]) == REG)
	{
	  rtx xoperands[2];
	  int offset = - get_frame_size () - 8;
	  xoperands[0] = GEN_INT (offset);
	  xoperands[1] = operands[1];
	  output_asm_insn ("st_dbl %1,r25,%0", xoperands);
	  xoperands[1] = operands[0];
	  output_asm_insn ("ld_32 %1,r25,%0\n\tnop", xoperands);
	  xoperands[1] = gen_rtx (REG, SImode, REGNO (operands[0]) + 1);
	  xoperands[0] = GEN_INT (offset + 4);
	  output_asm_insn ("ld_32 %1,r25,%0\n\tnop", xoperands);
	  return "";
	}
      return "st_dbl %1,%0";
    }
}

/* 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 ();
}

/* Generate code to add a large integer constant to register, reg, storing
 * the result in a register, target.  Offset must be 27-bit signed quantity */

static char *
output_add_large_offset (target, reg, offset)
     rtx target, reg;
     int offset;
{
  rtx operands[3];
  int high, n, i;
  operands[0] = target, operands[1] = reg;
    
  for (high = offset, n = 0; 
       (unsigned) (high + 0x2000) >= 0x4000; 
       high >>= 1, n += 1)
    ;
  operands[2] = GEN_INT (high);
  output_asm_insn ("add_nt r2,r0,%2", operands);
  i = n;
  while (i >= 3)
    output_asm_insn ("sll r2,r2,$3", operands), i -= 3;
  if (i == 2) 
    output_asm_insn ("sll r2,r2,$2", operands);
  else if (i == 1)
    output_asm_insn ("sll r2,r2,$1", operands);
  output_asm_insn ("add_nt %0,r2,%1", operands);
  if (offset - (high << n) != 0)
    {
      operands[2] = GEN_INT (offset - (high << n));
      output_asm_insn ("add_nt %0,%0,%2", operands);
    }
  return "";
}

/* Additional TESTFN for matching. Like immediate_operand, but matches big
 * constants */

int
big_immediate_operand (op, mode)
     rtx op;
     enum machine_mode mode;
{
  return (GET_CODE (op) == CONST_INT);
}