rs6000.c

gcc3.2.1源代码

  if (TARGET_MULTIPLE_SET)
    target_flags = (target_flags & ~MASK_MULTIPLE) | multiple;

  /* If -mstring or -mno-string was explicitly used, don't override
     with the processor default.  */
  if (TARGET_STRING_SET)
    target_flags = (target_flags & ~MASK_STRING) | string;

  /* Don't allow -mmultiple or -mstring on little endian systems
     unless the cpu is a 750, because the hardware doesn't support the
     instructions used in little endian mode, and causes an alignment
     trap.  The 750 does not cause an alignment trap (except when the
     target is unaligned).  */

  if (! BYTES_BIG_ENDIAN && rs6000_cpu != PROCESSOR_PPC750)
    {
      if (TARGET_MULTIPLE)
	{
	  target_flags &= ~MASK_MULTIPLE;
	  if (TARGET_MULTIPLE_SET)
	    warning ("-mmultiple is not supported on little endian systems");
	}

      if (TARGET_STRING)
	{
	  target_flags &= ~MASK_STRING;
	  if (TARGET_STRING_SET)
	    warning ("-mstring is not supported on little endian systems");
	}
    }

  if (flag_pic != 0 && DEFAULT_ABI == ABI_AIX)
    {
      flag_pic = 0;

      if (extra_warnings)
	warning ("-f%s ignored (all code is position independent)",
		 (flag_pic > 1) ? "PIC" : "pic");
    }

#ifdef XCOFF_DEBUGGING_INFO
  if (flag_function_sections && (write_symbols != NO_DEBUG)
      && DEFAULT_ABI == ABI_AIX)
    {
      warning ("-ffunction-sections disabled on AIX when debugging");
      flag_function_sections = 0;
    }

  if (flag_data_sections && (DEFAULT_ABI == ABI_AIX))
    {
      warning ("-fdata-sections not supported on AIX");
      flag_data_sections = 0;
    }
#endif

  /* Set debug flags */
  if (rs6000_debug_name)
    {
      if (! strcmp (rs6000_debug_name, "all"))
	rs6000_debug_stack = rs6000_debug_arg = 1;
      else if (! strcmp (rs6000_debug_name, "stack"))
	rs6000_debug_stack = 1;
      else if (! strcmp (rs6000_debug_name, "arg"))
	rs6000_debug_arg = 1;
      else
	error ("unknown -mdebug-%s switch", rs6000_debug_name);
    }

  /* Set size of long double */
  rs6000_long_double_type_size = 64;
  if (rs6000_long_double_size_string)
    {
      char *tail;
      int size = strtol (rs6000_long_double_size_string, &tail, 10);
      if (*tail != '\0' || (size != 64 && size != 128))
	error ("Unknown switch -mlong-double-%s",
	       rs6000_long_double_size_string);
      else
	rs6000_long_double_type_size = size;
    }

  /* Handle -mabi= options.  */
  rs6000_parse_abi_options ();

#ifdef TARGET_REGNAMES
  /* If the user desires alternate register names, copy in the
     alternate names now.  */
  if (TARGET_REGNAMES)
    memcpy (rs6000_reg_names, alt_reg_names, sizeof (rs6000_reg_names));
#endif

#ifdef SUBTARGET_OVERRIDE_OPTIONS
  SUBTARGET_OVERRIDE_OPTIONS;
#endif
#ifdef SUBSUBTARGET_OVERRIDE_OPTIONS
  SUBSUBTARGET_OVERRIDE_OPTIONS;
#endif

  /* Set TARGET_AIX_STRUCT_RET last, after the ABI is determined.
     If -maix-struct-return or -msvr4-struct-return was explicitly
     used, don't override with the ABI default.  */
  if (!(target_flags & MASK_AIX_STRUCT_RET_SET))
    {
      if (DEFAULT_ABI == ABI_V4 && !DRAFT_V4_STRUCT_RET)
	target_flags = (target_flags & ~MASK_AIX_STRUCT_RET);
      else
	target_flags |= MASK_AIX_STRUCT_RET;
    }

  /* Register global variables with the garbage collector.  */
  rs6000_add_gc_roots ();

  /* Allocate an alias set for register saves & restores from stack.  */
  rs6000_sr_alias_set = new_alias_set ();

  if (TARGET_TOC) 
    ASM_GENERATE_INTERNAL_LABEL (toc_label_name, "LCTOC", 1);

  /* We can only guarantee the availability of DI pseudo-ops when
     assembling for 64-bit targets.  */
  if (!TARGET_64BIT)
    {
      targetm.asm_out.aligned_op.di = NULL;
      targetm.asm_out.unaligned_op.di = NULL;
    }

  /* Arrange to save and restore machine status around nested functions.  */
  init_machine_status = rs6000_init_machine_status;
  free_machine_status = rs6000_free_machine_status;
}

/* Handle -mabi= options.  */
static void
rs6000_parse_abi_options ()
{
  if (rs6000_abi_string == 0)
    return;
  else if (! strcmp (rs6000_abi_string, "altivec"))
    rs6000_altivec_abi = 1;
  else if (! strcmp (rs6000_abi_string, "no-altivec"))
    rs6000_altivec_abi = 0;
  else
    error ("unknown ABI specified: '%s'", rs6000_abi_string);
}

void
optimization_options (level, size)
     int level ATTRIBUTE_UNUSED;
     int size ATTRIBUTE_UNUSED;
{
}

/* Do anything needed at the start of the asm file.  */

void
rs6000_file_start (file, default_cpu)
     FILE *file;
     const char *default_cpu;
{
  size_t i;
  char buffer[80];
  const char *start = buffer;
  struct rs6000_cpu_select *ptr;

  if (flag_verbose_asm)
    {
      sprintf (buffer, "\n%s rs6000/powerpc options:", ASM_COMMENT_START);
      rs6000_select[0].string = default_cpu;

      for (i = 0; i < ARRAY_SIZE (rs6000_select); i++)
	{
	  ptr = &rs6000_select[i];
	  if (ptr->string != (char *)0 && ptr->string[0] != '\0')
	    {
	      fprintf (file, "%s %s%s", start, ptr->name, ptr->string);
	      start = "";
	    }
	}

#ifdef USING_ELFOS_H
      switch (rs6000_sdata)
	{
	case SDATA_NONE: fprintf (file, "%s -msdata=none", start); start = ""; break;
	case SDATA_DATA: fprintf (file, "%s -msdata=data", start); start = ""; break;
	case SDATA_SYSV: fprintf (file, "%s -msdata=sysv", start); start = ""; break;
	case SDATA_EABI: fprintf (file, "%s -msdata=eabi", start); start = ""; break;
	}

      if (rs6000_sdata && g_switch_value)
	{
	  fprintf (file, "%s -G %d", start, g_switch_value);
	  start = "";
	}
#endif

      if (*start == '\0')
	putc ('\n', file);
    }
}


/* Create a CONST_DOUBLE from a string.  */

struct rtx_def *
rs6000_float_const (string, mode)
     const char *string;
     enum machine_mode mode;
{
  REAL_VALUE_TYPE value;
  value = REAL_VALUE_ATOF (string, mode);
  return immed_real_const_1 (value, mode);
}

/* Return non-zero if this function is known to have a null epilogue.  */

int
direct_return ()
{
  if (reload_completed)
    {
      rs6000_stack_t *info = rs6000_stack_info ();

      if (info->first_gp_reg_save == 32
	  && info->first_fp_reg_save == 64
	  && info->first_altivec_reg_save == LAST_ALTIVEC_REGNO + 1
	  && ! info->lr_save_p
	  && ! info->cr_save_p
	  && info->vrsave_mask == 0
	  && ! info->push_p)
	return 1;
    }

  return 0;
}

/* Returns 1 always.  */

int
any_operand (op, mode)
     rtx op ATTRIBUTE_UNUSED;
     enum machine_mode mode ATTRIBUTE_UNUSED;
{
  return 1;
}

/* Returns 1 if op is the count register.  */
int
count_register_operand (op, mode)
     rtx op;
     enum machine_mode mode ATTRIBUTE_UNUSED;
{
  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 an altivec register.  */
int
altivec_register_operand (op, mode)
     rtx op;
     enum machine_mode mode ATTRIBUTE_UNUSED;
{
  
  return (register_operand (op, mode)
	  && (GET_CODE (op) != REG
	      || REGNO (op) > FIRST_PSEUDO_REGISTER
	      || ALTIVEC_REGNO_P (REGNO (op))));
}

int
xer_operand (op, mode)
     rtx op;
     enum machine_mode mode ATTRIBUTE_UNUSED;
{
  if (GET_CODE (op) != REG)
    return 0;

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

  return 0;
}

/* Return 1 if OP is a signed 8-bit constant.  Int multiplication
   by such constants completes more quickly.  */

int
s8bit_cint_operand (op, mode)
     rtx op;
     enum machine_mode mode ATTRIBUTE_UNUSED;
{
  return ( GET_CODE (op) == CONST_INT
	  && (INTVAL (op) >= -128 && INTVAL (op) <= 127));
}

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

int
short_cint_operand (op, mode)
     rtx op;
     enum machine_mode mode ATTRIBUTE_UNUSED;
{
  return (GET_CODE (op) == CONST_INT
	  && CONST_OK_FOR_LETTER_P (INTVAL (op), 'I'));
}

/* Similar for an unsigned D field.  */

int
u_short_cint_operand (op, mode)
     rtx op;
     enum machine_mode mode ATTRIBUTE_UNUSED;
{
  return (GET_CODE (op) == CONST_INT
	  && CONST_OK_FOR_LETTER_P (INTVAL (op) & GET_MODE_MASK (mode), 'K'));
}

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

int
non_short_cint_operand (op, mode)
     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 CONST_INT that is a positive value
   and an exact power of 2.  */

int
exact_log2_cint_operand (op, mode)
     rtx op;
     enum machine_mode mode ATTRIBUTE_UNUSED;
{
  return (GET_CODE (op) == CONST_INT
	  && INTVAL (op) > 0
	  && exact_log2 (INTVAL (op)) >= 0);
}

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

int
gpc_reg_operand (op, mode)
     rtx op;
     enum machine_mode mode;
{
  return (register_operand (op, mode)
	  && (GET_CODE (op) != REG
	      || (REGNO (op) >= ARG_POINTER_REGNUM 
		  && !XER_REGNO_P (REGNO (op)))
	      || REGNO (op) < MQ_REGNO));
}

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

int
cc_reg_operand (op, mode)
     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)
     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)
      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)
      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);
}

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

int
reg_or_aligned_short_operand (op, mode)
      rtx op;
      enum machine_mode mode;
{
  if (gpc_reg_operand (op, mode))
    return 1;
  else if (short_cint_operand (op, mode) && !(INTVAL (op) & 3))
    return 1;

  return 0;
}


/* 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)
     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)
    rtx op;
    enum machine_mode mode;