alpha.c

linux下的gcc编译器

  if (SYMBOL_REF_FLAG (op) && decl_in_text_section (current_function_decl))
    return 1;

  return 0;
}

/* Return 1 if OP is a SYMBOL_REF for which we can make a call via bsr.  */

int
direct_call_operand (op, mode)
     rtx op;
     enum machine_mode mode;
{
  /* Must be defined in this file.  */
  if (! current_file_function_operand (op, mode))
    return 0;

  /* If profiling is implemented via linker tricks, we can't jump
     to the nogp alternate entry point.  */
  /* ??? TARGET_PROFILING_NEEDS_GP isn't really the right test,
     but is approximately correct for the OSF ABIs.  Don't know
     what to do for VMS, NT, or UMK.  */
  if (! TARGET_PROFILING_NEEDS_GP
      && ! current_function_profile)
    return 0;

  return 1;
}

/* Return true if OP is a LABEL_REF, or SYMBOL_REF or CONST referencing
   a (non-tls) variable known to be defined in this file.  */

int
local_symbolic_operand (op, mode)
     rtx op;
     enum machine_mode mode;
{
  const char *str;

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

  if (GET_CODE (op) == LABEL_REF)
    return 1;

  if (GET_CODE (op) == CONST
      && GET_CODE (XEXP (op, 0)) == PLUS
      && GET_CODE (XEXP (XEXP (op, 0), 1)) == CONST_INT)
    op = XEXP (XEXP (op, 0), 0);

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

  /* Easy pickings.  */
  if (CONSTANT_POOL_ADDRESS_P (op) || STRING_POOL_ADDRESS_P (op))
    return 1;

  /* ??? SYMBOL_REF_FLAG is set for local function symbols, but we
     run into problems with the rtl inliner in that the symbol was
     once external, but is local after inlining, which results in
     unrecognizable insns.  */

  str = XSTR (op, 0);

  /* If @[LS], then alpha_encode_section_info sez it's local.  */
  if (str[0] == '@' && (str[1] == 'L' || str[1] == 'S'))
    return 1;

  /* If *$, then ASM_GENERATE_INTERNAL_LABEL sez it's local.  */
  if (str[0] == '*' && str[1] == '$')
    return 1;

  return 0;
}

/* Return true if OP is a SYMBOL_REF or CONST referencing a variable
   known to be defined in this file in the small data area.  */

int
small_symbolic_operand (op, mode)
     rtx op;
     enum machine_mode mode ATTRIBUTE_UNUSED;
{
  const char *str;

  if (! TARGET_SMALL_DATA)
    return 0;

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

  if (GET_CODE (op) == CONST
      && GET_CODE (XEXP (op, 0)) == PLUS
      && GET_CODE (XEXP (XEXP (op, 0), 1)) == CONST_INT)
    op = XEXP (XEXP (op, 0), 0);

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

  if (CONSTANT_POOL_ADDRESS_P (op))
    return GET_MODE_SIZE (get_pool_mode (op)) <= (unsigned) g_switch_value;
  else
    {
      str = XSTR (op, 0);
      return str[0] == '@' && str[1] == 'S';
    }
}

/* Return true if OP is a SYMBOL_REF or CONST referencing a variable
   not known (or known not) to be defined in this file.  */

int
global_symbolic_operand (op, mode)
     rtx op;
     enum machine_mode mode;
{
  const char *str;

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

  if (GET_CODE (op) == CONST
      && GET_CODE (XEXP (op, 0)) == PLUS
      && GET_CODE (XEXP (XEXP (op, 0), 1)) == CONST_INT)
    op = XEXP (XEXP (op, 0), 0);

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

  if (local_symbolic_operand (op, mode))
    return 0;

  /* Also verify that it's not a TLS symbol.  */
  str = XSTR (op, 0);
  return str[0] != '%' && str[0] != '@';
}

/* Return 1 if OP is a valid operand for the MEM of a CALL insn.  */

int
call_operand (op, mode)
     rtx op;
     enum machine_mode mode;
{
  if (mode != Pmode)
    return 0;

  if (GET_CODE (op) == REG)
    {
      if (TARGET_ABI_OSF)
	{
	  /* Disallow virtual registers to cope with pathalogical test cases
	     such as compile/930117-1.c in which the virtual reg decomposes
	     to the frame pointer.  Which is a hard reg that is not $27.  */
	  return (REGNO (op) == 27 || REGNO (op) > LAST_VIRTUAL_REGISTER);
	}
      else
	return 1;
    }
  if (TARGET_ABI_UNICOSMK)
    return 0;
  if (GET_CODE (op) == SYMBOL_REF)
    return 1;

  return 0;
}

/* Returns 1 if OP is a symbolic operand, i.e. a symbol_ref or a label_ref,
   possibly with an offset.  */

int
symbolic_operand (op, mode)
      register rtx op;
      enum machine_mode mode;
{
  if (mode != VOIDmode && GET_MODE (op) != VOIDmode && mode != GET_MODE (op))
    return 0;
  if (GET_CODE (op) == SYMBOL_REF || GET_CODE (op) == LABEL_REF)
    return 1;
  if (GET_CODE (op) == CONST
      && GET_CODE (XEXP (op,0)) == PLUS
      && GET_CODE (XEXP (XEXP (op,0), 0)) == SYMBOL_REF
      && GET_CODE (XEXP (XEXP (op,0), 1)) == CONST_INT)
    return 1;
  return 0;
}

/* Return true if OP is valid for a particular TLS relocation.  */

static int
tls_symbolic_operand_1 (op, mode, size, unspec)
     rtx op;
     enum machine_mode mode;
     int size, unspec;
{
  const char *str;
  int letter;

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

  if (GET_CODE (op) != CONST)
    return 0;
  op = XEXP (op, 0);

  if (GET_CODE (op) != UNSPEC || XINT (op, 1) != unspec)
    return 0;
  op = XVECEXP (op, 0, 0);

  if (GET_CODE (op) != SYMBOL_REF)
    return 0;
  str = XSTR (op, 0);

  if (str[0] == '%')
    {
      if (size != 64)
	return 0;
    }
  else if (str[0] == '@')
    {
      if (alpha_tls_size > size)
	return 0;
    }
  else
    return 0;

  if (unspec == UNSPEC_DTPREL)
    return str[1] == 'D';
  else if (str[1] == 'I')
    return size == 64;
  else
    return str[1] == 'T';
}

/* Return true if OP is valid for 16-bit DTP relative relocations.  */

int
dtp16_symbolic_operand (op, mode)
      rtx op;
      enum machine_mode mode;
{
  return tls_symbolic_operand_1 (op, mode, 16, UNSPEC_DTPREL);
}

/* Return true if OP is valid for 32-bit DTP relative relocations.  */

int
dtp32_symbolic_operand (op, mode)
      rtx op;
      enum machine_mode mode;
{
  return tls_symbolic_operand_1 (op, mode, 32, UNSPEC_DTPREL);
}

/* Return true if OP is valid for 64-bit DTP relative relocations.  */

int
gotdtp_symbolic_operand (op, mode)
      rtx op;
      enum machine_mode mode;
{
  return tls_symbolic_operand_1 (op, mode, 64, UNSPEC_DTPREL);
}

/* Return true if OP is valid for 16-bit TP relative relocations.  */

int
tp16_symbolic_operand (op, mode)
      rtx op;
      enum machine_mode mode;
{
  return tls_symbolic_operand_1 (op, mode, 16, UNSPEC_TPREL);
}

/* Return true if OP is valid for 32-bit TP relative relocations.  */

int
tp32_symbolic_operand (op, mode)
      rtx op;
      enum machine_mode mode;
{
  return tls_symbolic_operand_1 (op, mode, 32, UNSPEC_TPREL);
}

/* Return true if OP is valid for 64-bit TP relative relocations.  */

int
gottp_symbolic_operand (op, mode)
      rtx op;
      enum machine_mode mode;
{
  return tls_symbolic_operand_1 (op, mode, 64, UNSPEC_TPREL);
}

/* Return 1 if OP is a valid Alpha comparison operator.  Here we know which
   comparisons are valid in which insn.  */

int
alpha_comparison_operator (op, mode)
     register rtx op;
     enum machine_mode mode;
{
  enum rtx_code code = GET_CODE (op);

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

  return (code == EQ || code == LE || code == LT
	  || code == LEU || code == LTU);
}

/* Return 1 if OP is a valid Alpha comparison operator against zero. 
   Here we know which comparisons are valid in which insn.  */

int
alpha_zero_comparison_operator (op, mode)
     register rtx op;
     enum machine_mode mode;
{
  enum rtx_code code = GET_CODE (op);

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

  return (code == EQ || code == NE || code == LE || code == LT
	  || code == LEU || code == LTU);
}

/* Return 1 if OP is a valid Alpha swapped comparison operator.  */

int
alpha_swapped_comparison_operator (op, mode)
     register rtx op;
     enum machine_mode mode;
{
  enum rtx_code code = GET_CODE (op);

  if ((mode != GET_MODE (op) && mode != VOIDmode)
      || GET_RTX_CLASS (code) != '<')
    return 0;

  code = swap_condition (code);
  return (code == EQ || code == LE || code == LT
	  || code == LEU || code == LTU);
}

/* Return 1 if OP is a signed comparison operation.  */

int
signed_comparison_operator (op, mode)
     register rtx op;
     enum machine_mode mode ATTRIBUTE_UNUSED;
{
  enum rtx_code code = GET_CODE (op);

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

  return (code == EQ || code == NE
	  || code == LE || code == LT
	  || code == GE || code == GT);
}

/* Return 1 if OP is a valid Alpha floating point comparison operator.
   Here we know which comparisons are valid in which insn.  */

int
alpha_fp_comparison_operator (op, mode)
     register rtx op;
     enum machine_mode mode;
{
  enum rtx_code code = GET_CODE (op);

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

  return (code == EQ || code == LE || code == LT || code == UNORDERED);
}

/* Return 1 if this is a divide or modulus operator.  */

int
divmod_operator (op, mode)
     register rtx op;
     enum machine_mode mode ATTRIBUTE_UNUSED;
{
  switch (GET_CODE (op))
    {
    case DIV:  case MOD:  case UDIV:  case UMOD:
      return 1;

    default:
      break;
    }

  return 0;
}

/* Return 1 if this memory address is a known aligned register plus
   a constant.  It must be a valid address.  This means that we can do
   this as an aligned reference plus some offset.

   Take into account what reload will do.  */

int
aligned_memory_operand (op, mode)
     register rtx op;
     enum machine_mode mode;
{
  rtx base;

  if (reload_in_progress)
    {
      rtx tmp = op;
      if (GET_CODE (tmp) == SUBREG)
	tmp = SUBREG_REG (tmp);
      if (GET_CODE (tmp) == REG
	  && REGNO (tmp) >= FIRST_PSEUDO_REGISTER)
	{
	  op = reg_equiv_memory_loc[REGNO (tmp)];
	  if (op == 0)
	    return 0;
	}
    }

  if (GET_CODE (op) != MEM
      || GET_MODE (op) != mode)
    return 0;
  op = XEXP (op, 0);

  /* LEGITIMIZE_RELOAD_ADDRESS creates (plus (plus reg const_hi) const_lo)
     sorts of constructs.  Dig for the real base register.  */
  if (reload_in_progress
      && GET_CODE (op) == PLUS
      && GET_CODE (XEXP (op, 0)) == PLUS)
    base = XEXP (XEXP (op, 0), 0);
  else
    {
      if (! memory_address_p (mode, op))
	return 0;
      base = (GET_CODE (op) == PLUS ? XEXP (op, 0) : op);
    }

  return (GET_CODE (base) == REG && REGNO_POINTER_ALIGN (REGNO (base)) >= 32);
}

/* Similar, but return 1 if OP is a MEM which is not alignable.  */

int
unaligned_memory_operand (op, mode)
     register rtx op;
     enum machine_mode mode;
{
  rtx base;

  if (reload_in_progress)
    {
      rtx tmp = op;
      if (GET_CODE (tmp) == SUBREG)
	tmp = SUBREG_REG (tmp);
      if (GET_CODE (tmp) == REG
	  && REGNO (tmp) >= FIRST_PSEUDO_REGISTER)
	{
	  op = reg_equiv_memory_loc[REGNO (tmp)];
	  if (op == 0)
	    return 0;
	}
    }

  if (GET_CODE (op) != MEM
      || GET_MODE (op) != mode)
    return 0;
  op = XEXP (op, 0);

  /* LEGITIMIZE_RELOAD_ADDRESS creates (plus (plus reg const_hi) const_lo)
     sorts of constructs.  Dig for the real base register.  */
  if (reload_in_progress
      && GET_CODE (op) == PLUS
      && GET_CODE (XEXP (op, 0)) == PLUS)
    base = XEXP (XEXP (op, 0), 0);
  else
    {
      if (! memory_address_p (mode, op))
	return 0;
      base = (GET_CODE (op) == PLUS ? XEXP (op, 0) : op);
    }

  return (GET_CODE (base) == REG && REGNO_POINTER_ALIGN (REGNO (base)) < 32);
}

/* Return 1 if OP is either a register or an unaligned memory location.  */