dwarfout.c

GUN开源阻止下的编译器GCC

	return FT_void;

      case INTEGER_TYPE:
	/* Carefully distinguish all the standard types of C,
	   without messing up if the language is not C.
	   Note that we check only for the names that contain spaces;
	   other names might occur by coincidence in other languages.  */
	if (TYPE_NAME (type) != 0
	    && TREE_CODE (TYPE_NAME (type)) == TYPE_DECL
	    && DECL_NAME (TYPE_NAME (type)) != 0
	    && TREE_CODE (DECL_NAME (TYPE_NAME (type))) == IDENTIFIER_NODE)
	  {
	    char *name = IDENTIFIER_POINTER (DECL_NAME (TYPE_NAME (type)));

	    if (!strcmp (name, "unsigned char"))
	      return FT_unsigned_char;
	    if (!strcmp (name, "signed char"))
	      return FT_signed_char;
	    if (!strcmp (name, "unsigned int"))
	      return FT_unsigned_integer;
	    if (!strcmp (name, "short int"))
	      return FT_short;
	    if (!strcmp (name, "short unsigned int"))
	      return FT_unsigned_short;
	    if (!strcmp (name, "long int"))
	      return FT_long;
	    if (!strcmp (name, "long unsigned int"))
	      return FT_unsigned_long;
	    if (!strcmp (name, "long long int"))
	      return FT_long_long;		/* Not grok'ed by svr4 SDB */
	    if (!strcmp (name, "long long unsigned int"))
	      return FT_unsigned_long_long;	/* Not grok'ed by svr4 SDB */
	  }

	/* Most integer types will be sorted out above, however, for the
	   sake of special `array index' integer types, the following code
	   is also provided.  */

	if (TYPE_PRECISION (type) == INT_TYPE_SIZE)
	  return (TREE_UNSIGNED (type) ? FT_unsigned_integer : FT_integer);

	if (TYPE_PRECISION (type) == LONG_TYPE_SIZE)
	  return (TREE_UNSIGNED (type) ? FT_unsigned_long : FT_long);

	if (TYPE_PRECISION (type) == LONG_LONG_TYPE_SIZE)
	  return (TREE_UNSIGNED (type) ? FT_unsigned_long_long : FT_long_long);

	if (TYPE_PRECISION (type) == SHORT_TYPE_SIZE)
	  return (TREE_UNSIGNED (type) ? FT_unsigned_short : FT_short);

	if (TYPE_PRECISION (type) == CHAR_TYPE_SIZE)
	  return (TREE_UNSIGNED (type) ? FT_unsigned_char : FT_char);

	abort ();

      case REAL_TYPE:
	/* Carefully distinguish all the standard types of C,
	   without messing up if the language is not C.  */
	if (TYPE_NAME (type) != 0
	    && TREE_CODE (TYPE_NAME (type)) == TYPE_DECL
	    && DECL_NAME (TYPE_NAME (type)) != 0
	    && TREE_CODE (DECL_NAME (TYPE_NAME (type))) == IDENTIFIER_NODE)
	  {
	    char *name = IDENTIFIER_POINTER (DECL_NAME (TYPE_NAME (type)));

	    /* Note that here we can run afowl of a serious bug in "classic"
	       svr4 SDB debuggers.  They don't seem to understand the
	       FT_ext_prec_float type (even though they should).  */

	    if (!strcmp (name, "long double"))
	      return FT_ext_prec_float;
	  }

	if (TYPE_PRECISION (type) == DOUBLE_TYPE_SIZE)
	  return FT_dbl_prec_float;
	if (TYPE_PRECISION (type) == FLOAT_TYPE_SIZE)
	  return FT_float;

	/* Note that here we can run afowl of a serious bug in "classic"
	   svr4 SDB debuggers.  They don't seem to understand the
	   FT_ext_prec_float type (even though they should).  */

	if (TYPE_PRECISION (type) == LONG_DOUBLE_TYPE_SIZE)
	  return FT_ext_prec_float;
	abort ();

      case COMPLEX_TYPE:
	return FT_complex;	/* GNU FORTRAN COMPLEX type.  */

      case CHAR_TYPE:
	return FT_char;		/* GNU Pascal CHAR type.  Not used in C.  */

      case BOOLEAN_TYPE:
	return FT_boolean;	/* GNU FORTRAN BOOLEAN type.  */

      default:
	abort ();	/* No other TREE_CODEs are Dwarf fundamental types.  */
    }
  return 0;
}

/* Given a pointer to an arbitrary ..._TYPE tree node, return a pointer to
   the Dwarf "root" type for the given input type.  The Dwarf "root" type
   of a given type is generally the same as the given type, except that if
   the	given type is a pointer or reference type, then the root type of
   the given type is the root type of the "basis" type for the pointer or
   reference type.  (This definition of the "root" type is recursive.)
   Also, the root type of a `const' qualified type or a `volatile'
   qualified type is the root type of the given type without the
   qualifiers.  */

static tree
root_type (type)
     register tree type;
{
  if (TREE_CODE (type) == ERROR_MARK)
    return error_mark_node;

  switch (TREE_CODE (type))
    {
      case ERROR_MARK:
	return error_mark_node;

      case POINTER_TYPE:
      case REFERENCE_TYPE:
	return type_main_variant (root_type (TREE_TYPE (type)));

      default:
	return type_main_variant (type);
    }
}

/* Given a pointer to an arbitrary ..._TYPE tree node, write out a sequence
   of zero or more Dwarf "type-modifier" bytes applicable to the type.	*/

static void
write_modifier_bytes (type, decl_const, decl_volatile)
     register tree type;
     register int decl_const;
     register int decl_volatile;
{
  if (TREE_CODE (type) == ERROR_MARK)
    return;

  if (TYPE_READONLY (type) || decl_const)
    ASM_OUTPUT_DWARF_TYPE_MODIFIER (asm_out_file, MOD_const);
  if (TYPE_VOLATILE (type) || decl_volatile)
    ASM_OUTPUT_DWARF_TYPE_MODIFIER (asm_out_file, MOD_volatile);
  switch (TREE_CODE (type))
    {
      case POINTER_TYPE:
	ASM_OUTPUT_DWARF_TYPE_MODIFIER (asm_out_file, MOD_pointer_to);
	write_modifier_bytes (TREE_TYPE (type), 0, 0);
	return;

      case REFERENCE_TYPE:
	ASM_OUTPUT_DWARF_TYPE_MODIFIER (asm_out_file, MOD_reference_to);
	write_modifier_bytes (TREE_TYPE (type), 0, 0);
	return;

      case ERROR_MARK:
      default:
	return;
    }
}

/* Given a pointer to an arbitrary ..._TYPE tree node, return non-zero if the
   given input type is a Dwarf "fundamental" type.  Otherwise return zero.  */

inline int
type_is_fundamental (type)
     register tree type;
{
  switch (TREE_CODE (type))
    {
      case ERROR_MARK:
      case VOID_TYPE:
      case INTEGER_TYPE:
      case REAL_TYPE:
      case COMPLEX_TYPE:
      case BOOLEAN_TYPE:
      case CHAR_TYPE:
	return 1;

      case SET_TYPE:
      case ARRAY_TYPE:
      case RECORD_TYPE:
      case UNION_TYPE:
      case QUAL_UNION_TYPE:
      case ENUMERAL_TYPE:
      case FUNCTION_TYPE:
      case METHOD_TYPE:
      case POINTER_TYPE:
      case REFERENCE_TYPE:
      case FILE_TYPE:
      case OFFSET_TYPE:
      case LANG_TYPE:
	return 0;

      default:
	abort ();
    }
  return 0;
}

/* Given a pointer to some ..._DECL tree node, generate an assembly language
   equate directive which will associate a symbolic name with the current DIE.

   The name used is an artificial label generated from the DECL_UID number
   associated with the given decl node.  The name it gets equated to is the
   symbolic label that we (previously) output at the start of the DIE that
   we are currently generating.

   Calling this function while generating some "decl related" form of DIE
   makes it possible to later refer to the DIE which represents the given
   decl simply by re-generating the symbolic name from the ..._DECL node's
   UID number.	*/

static void
equate_decl_number_to_die_number (decl)
     register tree decl;
{
  /* In the case where we are generating a DIE for some ..._DECL node
     which represents either some inline function declaration or some
     entity declared within an inline function declaration/definition,
     setup a symbolic name for the current DIE so that we have a name
     for this DIE that we can easily refer to later on within
     AT_abstract_origin attributes.  */

  char decl_label[MAX_ARTIFICIAL_LABEL_BYTES];
  char die_label[MAX_ARTIFICIAL_LABEL_BYTES];

  sprintf (decl_label, DECL_NAME_FMT, DECL_UID (decl));
  sprintf (die_label, DIE_BEGIN_LABEL_FMT, current_dienum);
  ASM_OUTPUT_DEF (asm_out_file, decl_label, die_label);
}

/* Given a pointer to some ..._TYPE tree node, generate an assembly language
   equate directive which will associate a symbolic name with the current DIE.

   The name used is an artificial label generated from the TYPE_UID number
   associated with the given type node.  The name it gets equated to is the
   symbolic label that we (previously) output at the start of the DIE that
   we are currently generating.

   Calling this function while generating some "type related" form of DIE
   makes it easy to later refer to the DIE which represents the given type
   simply by re-generating the alternative name from the ..._TYPE node's
   UID number.	*/

inline void
equate_type_number_to_die_number (type)
     register tree type;
{
  char type_label[MAX_ARTIFICIAL_LABEL_BYTES];
  char die_label[MAX_ARTIFICIAL_LABEL_BYTES];

  /* We are generating a DIE to represent the main variant of this type
     (i.e the type without any const or volatile qualifiers) so in order
     to get the equate to come out right, we need to get the main variant
     itself here.  */

  type = type_main_variant (type);

  sprintf (type_label, TYPE_NAME_FMT, TYPE_UID (type));
  sprintf (die_label, DIE_BEGIN_LABEL_FMT, current_dienum);
  ASM_OUTPUT_DEF (asm_out_file, type_label, die_label);
}

static void
output_reg_number (rtl)
     register rtx rtl;
{
  register unsigned regno = REGNO (rtl);

  if (regno >= FIRST_PSEUDO_REGISTER)
    {
      warning_with_decl (dwarf_last_decl, "internal regno botch: regno = %d\n",
			 regno);
      regno = 0;
    }
  fprintf (asm_out_file, "\t%s\t0x%x",
	   UNALIGNED_INT_ASM_OP, DBX_REGISTER_NUMBER (regno));
  if (flag_verbose_asm)
    {
      fprintf (asm_out_file, "\t%s ", ASM_COMMENT_START);
      PRINT_REG (rtl, 0, asm_out_file);
    }
  fputc ('\n', asm_out_file);
}

/* The following routine is a nice and simple transducer.  It converts the
   RTL for a variable or parameter (resident in memory) into an equivalent
   Dwarf representation of a mechanism for getting the address of that same
   variable onto the top of a hypothetical "address evaluation" stack.

   When creating memory location descriptors, we are effectively trans-
   forming the RTL for a memory-resident object into its Dwarf postfix
   expression equivalent.  This routine just recursively descends an
   RTL tree, turning it into Dwarf postfix code as it goes.  */

static void
output_mem_loc_descriptor (rtl)
      register rtx rtl;
{
  /* Note that for a dynamically sized array, the location we will
     generate a description of here will be the lowest numbered location
     which is actually within the array.  That's *not* necessarily the
     same as the zeroth element of the array.  */

  switch (GET_CODE (rtl))
    {
      case SUBREG:

	/* The case of a subreg may arise when we have a local (register)
	   variable or a formal (register) parameter which doesn't quite
	   fill up an entire register.	For now, just assume that it is
	   legitimate to make the Dwarf info refer to the whole register
	   which contains the given subreg.  */

	rtl = XEXP (rtl, 0);
	/* Drop thru.  */

      case REG:

	/* Whenever a register number forms a part of the description of
	   the method for calculating the (dynamic) address of a memory
	   resident object, DWARF rules require the register number to
	   be referred to as a "base register".  This distinction is not
	   based in any way upon what category of register the hardware
	   believes the given register belongs to.  This is strictly
	   DWARF terminology we're dealing with here.

	   Note that in cases where the location of a memory-resident data
	   object could be expressed as:

		    OP_ADD (OP_BASEREG (basereg), OP_CONST (0))

	   the actual DWARF location descriptor that we generate may just
	   be OP_BASEREG (basereg).  This may look deceptively like the
	   object in question was allocated to a register (rather than
	   in memory) so DWARF consumers need to be aware of the subtle
	   distinction between OP_REG and OP_BASEREG.  */

	ASM_OUTPUT_DWARF_STACK_OP (asm_out_file, OP_BASEREG);
	output_reg_number (rtl);
	break;

      case MEM:
	output_mem_loc_descriptor (XEXP (rtl, 0));
	ASM_OUTPUT_DWARF_STACK_OP (asm_out_file, OP_DEREF4);
	break;

      case CONST:
      case SYMBOL_REF:
	ASM_OUTPUT_DWARF_STACK_OP (asm_out_file, OP_ADDR);
	ASM_OUTPUT_DWARF_ADDR_CONST (asm_out_file, rtl);
	break;

      case PLUS:
	output_mem_loc_descriptor (XEXP (rtl, 0));
	output_mem_loc_descriptor (XEXP (rtl, 1));
	ASM_OUTPUT_DWARF_STACK_OP (asm_out_file, OP_ADD);
	break;

      case CONST_INT:
	ASM_OUTPUT_DWARF_STACK_OP (asm_out_file, OP_CONST);
	ASM_OUTPUT_DWARF_DATA4 (asm_out_file, INTVAL (rtl));
	break;

      default:
	abort ();
    }
}

/* Output a proper Dwarf location descriptor for a variable or parameter
   which is either allocated in a register or in a memory location.  For
   a register, we just generate an OP_REG and the register number.  For a
   memory location we provide a Dwarf postfix expression describing how to
   generate the (dynamic) address of the object onto the address stack.  */

static void
output_loc_descriptor (rtl)
     register rtx rtl;
{
  switch (GET_CODE (rtl))
    {
    case SUBREG:

	/* The case of a subreg may arise when we have a local (register)
	   variable or a formal (register) parameter which doesn't quite
	   fill up an entire register.	For now, just assume that it is
	   legitimate to make the Dwarf info refer to the whole register
	   which contains the given subreg.  */

	rtl = XEXP (rtl, 0);
	/* Drop thru.  */

    case REG:
	ASM_OUTPUT_DWARF_STACK_OP (asm_out_file, OP_REG);
	output_reg_number (rtl);
	break;