rs6000.c

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  if (GET_CODE (op) != REG)
    return 0;

  if (REGNO (op) == COUNT_REGISTER_REGNUM)
    return 1;

  if (REGNO (op) > FIRST_PSEUDO_REGISTER)
    return 1;

  return 0;
}

/* Returns 1 if op is memory location for float/int conversions that masquerades
   as a register.  */
int
fpmem_operand(op, mode)
     register rtx op;
     enum machine_mode mode ATTRIBUTE_UNUSED;
{
  if (GET_CODE (op) != REG)
    return 0;

  if (FPMEM_REGNO_P (REGNO (op)))
    return 1;

#if 0
  if (REGNO (op) > FIRST_PSEUDO_REGISTER)
    return 1;
#endif

  return 0;
}

/* Return 1 if OP is a constant that can fit in a D field.  */

int
short_cint_operand (op, mode)
     register rtx op;
     enum machine_mode mode ATTRIBUTE_UNUSED;
{
  return ((GET_CODE (op) == CONST_INT
	   && (unsigned HOST_WIDE_INT) (INTVAL (op) + 0x8000) < 0x10000));
}

/* Similar for a unsigned D field.  */

int
u_short_cint_operand (op, mode)
     register rtx op;
     enum machine_mode mode ATTRIBUTE_UNUSED;
{
  return (GET_CODE (op) == CONST_INT
	   && (INTVAL (op) & (~ (HOST_WIDE_INT) 0xffff)) == 0);
}

/* Return 1 if OP is a CONST_INT that cannot fit in a signed D field.  */

int
non_short_cint_operand (op, mode)
     register rtx op;
     enum machine_mode mode ATTRIBUTE_UNUSED;
{
  return (GET_CODE (op) == CONST_INT
	  && (unsigned HOST_WIDE_INT) (INTVAL (op) + 0x8000) >= 0x10000);
}

/* Returns 1 if OP is a register that is not special (i.e., not MQ,
   ctr, or lr).  */

int
gpc_reg_operand (op, mode)
     register rtx op;
     enum machine_mode mode;
{
  return (register_operand (op, mode)
	  && (GET_CODE (op) != REG
	      || (REGNO (op) >= 67 && !FPMEM_REGNO_P (REGNO (op)))
	      || REGNO (op) < 64));
}

/* Returns 1 if OP is either a pseudo-register or a register denoting a
   CR field.  */

int
cc_reg_operand (op, mode)
     register rtx op;
     enum machine_mode mode;
{
  return (register_operand (op, mode)
	  && (GET_CODE (op) != REG
	      || REGNO (op) >= FIRST_PSEUDO_REGISTER
	      || CR_REGNO_P (REGNO (op))));
}

/* Returns 1 if OP is either a pseudo-register or a register denoting a
   CR field that isn't CR0.  */

int
cc_reg_not_cr0_operand (op, mode)
     register rtx op;
     enum machine_mode mode;
{
  return (register_operand (op, mode)
	  && (GET_CODE (op) != REG
	      || REGNO (op) >= FIRST_PSEUDO_REGISTER
	      || CR_REGNO_NOT_CR0_P (REGNO (op))));
}

/* Returns 1 if OP is either a constant integer valid for a D-field or a
   non-special register.  If a register, it must be in the proper mode unless
   MODE is VOIDmode.  */

int
reg_or_short_operand (op, mode)
      register rtx op;
      enum machine_mode mode;
{
  return short_cint_operand (op, mode) || gpc_reg_operand (op, mode);
}

/* Similar, except check if the negation of the constant would be valid for
   a D-field.  */

int
reg_or_neg_short_operand (op, mode)
      register rtx op;
      enum machine_mode mode;
{
  if (GET_CODE (op) == CONST_INT)
    return CONST_OK_FOR_LETTER_P (INTVAL (op), 'P');

  return gpc_reg_operand (op, mode);
}

/* Return 1 if the operand is either a register or an integer whose high-order
   16 bits are zero.  */

int
reg_or_u_short_operand (op, mode)
     register rtx op;
     enum machine_mode mode;
{
  return u_short_cint_operand (op, mode) || gpc_reg_operand (op, mode);
}

/* Return 1 is the operand is either a non-special register or ANY
   constant integer.  */

int
reg_or_cint_operand (op, mode)
    register rtx op;
    enum machine_mode mode;
{
     return (GET_CODE (op) == CONST_INT
	     || gpc_reg_operand (op, mode));
}

/* Return 1 is the operand is either a non-special register or ANY
   32-bit unsigned constant integer.  */

int
reg_or_u_cint_operand (op, mode)
    register rtx op;
    enum machine_mode mode;
{
     return (gpc_reg_operand (op, mode)
	     || (GET_CODE (op) == CONST_INT
#if HOST_BITS_PER_WIDE_INT != 32
		 && INTVAL (op) < ((HOST_WIDE_INT) 1 << 32)
#endif
		 && INTVAL (op) > 0)
#if HOST_BITS_PER_WIDE_INT == 32
	     || (GET_CODE (op) == CONST_DOUBLE
		 && CONST_DOUBLE_HIGH (op) == 0)
#endif
	 );
}

/* Return 1 if the operand is an operand that can be loaded via the GOT */

int
got_operand (op, mode)
     register rtx op;
     enum machine_mode mode ATTRIBUTE_UNUSED;
{
  return (GET_CODE (op) == SYMBOL_REF
	  || GET_CODE (op) == CONST
	  || GET_CODE (op) == LABEL_REF);
}

/* Return 1 if the operand is a simple references that can be loaded via
   the GOT (labels involving addition aren't allowed).  */

int
got_no_const_operand (op, mode)
     register rtx op;
     enum machine_mode mode ATTRIBUTE_UNUSED;
{
  return (GET_CODE (op) == SYMBOL_REF || GET_CODE (op) == LABEL_REF);
}

/* Return the number of instructions it takes to form a constant in an
   integer register.  */

static int
num_insns_constant_wide (value)
     HOST_WIDE_INT value;
{
  /* signed constant loadable with {cal|addi} */
  if (((unsigned HOST_WIDE_INT)value + 0x8000) < 0x10000)
    return 1;

#if HOST_BITS_PER_WIDE_INT == 32
  /* constant loadable with {cau|addis} */
  else if ((value & 0xffff) == 0)
    return 1;

#else
  /* constant loadable with {cau|addis} */
  else if ((value & 0xffff) == 0 && (value & ~0xffffffff) == 0)
    return 1;

  else if (TARGET_64BIT)
    {
      HOST_WIDE_INT low  = value & 0xffffffff;
      HOST_WIDE_INT high = value >> 32;

      if (high == 0 && (low & 0x80000000) == 0)
	return 2;

      else if (high == 0xffffffff && (low & 0x80000000) != 0)
	return 2;

      else if (!low)
	return num_insns_constant_wide (high) + 1;

      else
	return (num_insns_constant_wide (high)
		+ num_insns_constant_wide (low) + 1);
    }
#endif

  else
    return 2;
}

int
num_insns_constant (op, mode)
     rtx op;
     enum machine_mode mode;
{
  if (GET_CODE (op) == CONST_INT)
    return num_insns_constant_wide (INTVAL (op));

  else if (GET_CODE (op) == CONST_DOUBLE && mode == SFmode)
    {
      long l;
      REAL_VALUE_TYPE rv;

      REAL_VALUE_FROM_CONST_DOUBLE (rv, op);
      REAL_VALUE_TO_TARGET_SINGLE (rv, l);
      return num_insns_constant_wide ((HOST_WIDE_INT)l);
    }

  else if (GET_CODE (op) == CONST_DOUBLE)
    {
      HOST_WIDE_INT low;
      HOST_WIDE_INT high;
      long l[2];
      REAL_VALUE_TYPE rv;
      int endian = (WORDS_BIG_ENDIAN == 0);

      if (mode == VOIDmode || mode == DImode)
	{
	  high = CONST_DOUBLE_HIGH (op);
	  low  = CONST_DOUBLE_LOW (op);
	}
      else
	{
	  REAL_VALUE_FROM_CONST_DOUBLE (rv, op);
	  REAL_VALUE_TO_TARGET_DOUBLE (rv, l);
	  high = l[endian];
	  low  = l[1 - endian];
	}

      if (TARGET_32BIT)
	return (num_insns_constant_wide (low)
		+ num_insns_constant_wide (high));

      else
	{
	  if (high == 0 && (low & 0x80000000) == 0)
	    return num_insns_constant_wide (low);

	  else if (((high & 0xffffffff) == 0xffffffff)
		   && ((low & 0x80000000) != 0))
	    return num_insns_constant_wide (low);

	  else if (mask64_operand (op, mode))
	    return 2;

	  else if (low == 0)
	    return num_insns_constant_wide (high) + 1;

	  else
	    return (num_insns_constant_wide (high)
		    + num_insns_constant_wide (low) + 1);
	}
    }

  else
    abort ();
}

/* Return 1 if the operand is a CONST_DOUBLE and it can be put into a register
   with one instruction per word.  We only do this if we can safely read
   CONST_DOUBLE_{LOW,HIGH}.  */

int
easy_fp_constant (op, mode)
     register rtx op;
     register enum machine_mode mode;
{
  if (GET_CODE (op) != CONST_DOUBLE
      || GET_MODE (op) != mode
      || (GET_MODE_CLASS (mode) != MODE_FLOAT && mode != DImode))
    return 0;

  /* Consider all constants with -msoft-float to be easy */
  if (TARGET_SOFT_FLOAT && mode != DImode)
    return 1;

  /* If we are using V.4 style PIC, consider all constants to be hard */
  if (flag_pic && (DEFAULT_ABI == ABI_V4 || DEFAULT_ABI == ABI_SOLARIS))
    return 0;

#ifdef TARGET_RELOCATABLE
  /* Similarly if we are using -mrelocatable, consider all constants to be hard */
  if (TARGET_RELOCATABLE)
    return 0;
#endif

  if (mode == DFmode)
    {
      long k[2];
      REAL_VALUE_TYPE rv;

      REAL_VALUE_FROM_CONST_DOUBLE (rv, op);
      REAL_VALUE_TO_TARGET_DOUBLE (rv, k);

      return (num_insns_constant_wide ((HOST_WIDE_INT)k[0]) == 1
	      && num_insns_constant_wide ((HOST_WIDE_INT)k[1]) == 1);
    }

  else if (mode == SFmode)
    {
      long l;
      REAL_VALUE_TYPE rv;

      REAL_VALUE_FROM_CONST_DOUBLE (rv, op);
      REAL_VALUE_TO_TARGET_SINGLE (rv, l);

      return num_insns_constant_wide (l) == 1;
    }

  else if (mode == DImode)
    return ((TARGET_64BIT
	     && GET_CODE (op) == CONST_DOUBLE && CONST_DOUBLE_LOW (op) == 0)
	    || (num_insns_constant (op, DImode) <= 2));

  else
    abort ();
}

/* Return 1 if the operand is in volatile memory.  Note that during the
   RTL generation phase, memory_operand does not return TRUE for
   volatile memory references.  So this function allows us to
   recognize volatile references where its safe.  */

int
volatile_mem_operand (op, mode)
     register rtx op;
     enum machine_mode mode;
{
  if (GET_CODE (op) != MEM)
    return 0;

  if (!MEM_VOLATILE_P (op))
    return 0;

  if (mode != GET_MODE (op))
    return 0;

  if (reload_completed)
    return memory_operand (op, mode);

  if (reload_in_progress)
    return strict_memory_address_p (mode, XEXP (op, 0));

  return memory_address_p (mode, XEXP (op, 0));
}

/* Return 1 if the operand is an offsettable memory operand.  */

int
offsettable_mem_operand (op, mode)
     register rtx op;
     enum machine_mode mode;
{
  return ((GET_CODE (op) == MEM)
	  && offsettable_address_p (reload_completed || reload_in_progress,
				    mode, XEXP (op, 0)));
}

/* Return 1 if the operand is either an easy FP constant (see above) or
   memory.  */

int
mem_or_easy_const_operand (op, mode)
     register rtx op;
     enum machine_mode mode;
{
  return memory_operand (op, mode) || easy_fp_constant (op, mode);
}

/* Return 1 if the operand is either a non-special register or an item
   that can be used as the operand of an SI add insn.  */

int
add_operand (op, mode)
    register rtx op;
    enum machine_mode mode;
{
  return (reg_or_short_operand (op, mode)
	  || (GET_CODE (op) == CONST_INT
	      && (INTVAL (op) & (~ (HOST_WIDE_INT) 0xffff0000)) == 0));
}

/* Return 1 if OP is a constant but not a valid add_operand.  */

int
non_add_cint_operand (op, mode)
     register rtx op;
     enum machine_mode mode ATTRIBUTE_UNUSED;
{
  return (GET_CODE (op) == CONST_INT
	  && (unsigned HOST_WIDE_INT) (INTVAL (op) + 0x8000) >= 0x10000
	  && (INTVAL (op) & (~ (HOST_WIDE_INT) 0xffff0000)) != 0);
}

/* Return 1 if the operand is a non-special register or a constant that
   can be used as the operand of an OR or XOR insn on the RS/6000.  */

int
logical_operand (op, mode)
     register rtx op;
     enum machine_mode mode;
{
  return (gpc_reg_operand (op, mode)
	  || (GET_CODE (op) == CONST_INT
#if HOST_BITS_PER_WIDE_INT != 32
	      && INTVAL (op) > 0
	      && INTVAL (op) < ((HOST_WIDE_INT) 1 << 32)
#endif
	      && ((INTVAL (op) & GET_MODE_MASK (mode)
		   & (~ (HOST_WIDE_INT) 0xffff)) == 0
		  || (INTVAL (op) & GET_MODE_MASK (mode)
		      & (~ (unsigned HOST_WIDE_INT) 0xffff0000u)) == 0)));
}