error.c

gcc库的原代码,对编程有很大帮助.

    case REAL_CST:
#ifndef REAL_IS_NOT_DOUBLE
      sprintf (digit_buffer, "%g", TREE_REAL_CST (t));
#else
      {
	unsigned char *p = (unsigned char *) &TREE_REAL_CST (t);
	int i;
	strcpy (digit_buffer, "0x");
	for (i = 0; i < sizeof TREE_REAL_CST (t); i++)
	  sprintf (digit_buffer + 2 + 2*i, "%02x", *p++);
      }
#endif
      OB_PUTCP (digit_buffer);
      break;

    case STRING_CST:
      {
	char *p = TREE_STRING_POINTER (t);
	int len = TREE_STRING_LENGTH (t) - 1;
	int i;

	OB_PUTC ('\"');
	for (i = 0; i < len; i++)
	  dump_char (p[i]);
	OB_PUTC ('\"');
      }
      break;

    case COMPOUND_EXPR:
      dump_binary_op (",", t);
      break;

    case COND_EXPR:
      OB_PUTC ('(');
      dump_expr (TREE_OPERAND (t, 0), 0);
      OB_PUTS (" ? ");
      dump_expr (TREE_OPERAND (t, 1), 0);
      OB_PUTS (" : ");
      dump_expr (TREE_OPERAND (t, 2), 0);
      OB_PUTC (')');
      break;

    case SAVE_EXPR:
      if (TREE_HAS_CONSTRUCTOR (t))
	{
	  OB_PUTS ("new ");
	  dump_type (TREE_TYPE (TREE_TYPE (t)), 0);
	  PARM_DECL_EXPR (t) = 1;
	}
      else
	{
	  dump_expr (TREE_OPERAND (t, 0), 0);
	}
      break;

    case NEW_EXPR:
      OB_PUTID (TYPE_IDENTIFIER (TREE_TYPE (t)));
      OB_PUTC ('(');
      dump_expr_list (TREE_CHAIN (TREE_OPERAND (t, 1)));
      OB_PUTC (')');
      break;

    case CALL_EXPR:
      {
	tree fn = TREE_OPERAND (t, 0);
	tree args = TREE_OPERAND (t, 1);
	
	if (TREE_CODE (fn) == ADDR_EXPR)
	  fn = TREE_OPERAND (fn, 0);

	if (NEXT_CODE (fn) == METHOD_TYPE)
	  {
	    tree ob = TREE_VALUE (args);
	    if (TREE_CODE (ob) == ADDR_EXPR)
	      {
		dump_expr (TREE_OPERAND (ob, 0), 0);
		OB_PUTC ('.');
	      }
	    else if (TREE_CODE (ob) != PARM_DECL
		     || strcmp (IDENTIFIER_POINTER (DECL_NAME (ob)), "this"))
	      {
		dump_expr (ob, 0);
		OB_PUTC2 ('-', '>');
	      }
	    args = TREE_CHAIN (args);
	  }
	dump_expr (fn, 0);
	OB_PUTC('(');
	dump_expr_list (args);
	OB_PUTC (')');
      }
      break;

    case WITH_CLEANUP_EXPR:
      /* Note that this only works for G++ cleanups.  If somebody
	 builds a general cleanup, there's no way to represent it.  */
      dump_expr (TREE_OPERAND (t, 0), 0);
      break;

    case TARGET_EXPR:
      /* Note that this only works for G++ target exprs.  If somebody
	 builds a general TARGET_EXPR, there's no way to represent that
	 it initializes anything other that the parameter slot for the
	 default argument.  Note we may have cleared out the first
	 operand in expand_expr, so don't go killing ourselves.  */
      if (TREE_OPERAND (t, 1))
	dump_expr (TREE_OPERAND (t, 1), 0);
      break;

    case MODIFY_EXPR:
    case PLUS_EXPR:
    case MINUS_EXPR:
    case MULT_EXPR:
    case TRUNC_DIV_EXPR:
    case TRUNC_MOD_EXPR:
    case MIN_EXPR:
    case MAX_EXPR:
    case LSHIFT_EXPR:
    case RSHIFT_EXPR:
    case BIT_IOR_EXPR:
    case BIT_XOR_EXPR:
    case BIT_AND_EXPR:
    case BIT_ANDTC_EXPR:
    case TRUTH_ANDIF_EXPR:
    case TRUTH_ORIF_EXPR:
    case LT_EXPR:
    case LE_EXPR:
    case GT_EXPR:
    case GE_EXPR:
    case EQ_EXPR:
    case NE_EXPR:
      dump_binary_op (opname_tab[(int) TREE_CODE (t)], t);
      break;

    case CEIL_DIV_EXPR:
    case FLOOR_DIV_EXPR:
    case ROUND_DIV_EXPR:
      dump_binary_op ("/", t);
      break;

    case CEIL_MOD_EXPR:
    case FLOOR_MOD_EXPR:
    case ROUND_MOD_EXPR:
      dump_binary_op ("%", t);
      break;

    case COMPONENT_REF:
      {
	tree ob = TREE_OPERAND (t, 0);
	if (TREE_CODE (ob) == INDIRECT_REF)
	  {
	    ob = TREE_OPERAND (ob, 0);
	    if (TREE_CODE (ob) != PARM_DECL
		|| strcmp (IDENTIFIER_POINTER (DECL_NAME (ob)), "this"))
	      {
		dump_expr (ob, 0);
		OB_PUTC2 ('-', '>');
	      }
	  }
	else
	  {
	    dump_expr (ob, 0);
	    OB_PUTC ('.');
	  }
	dump_expr (TREE_OPERAND (t, 1), 1);
      }
      break;

    case ARRAY_REF:
      dump_expr (TREE_OPERAND (t, 0), 0);
      OB_PUTC ('[');
      dump_expr (TREE_OPERAND (t, 1), 0);
      OB_PUTC (']');
      break;

    case CONVERT_EXPR:
      dump_unary_op ("+", t, nop);
      break;

    case ADDR_EXPR:
      if (TREE_CODE (TREE_OPERAND (t, 0)) == FUNCTION_DECL
	  || TREE_CODE (TREE_OPERAND (t, 0)) == STRING_CST)
	dump_expr (TREE_OPERAND (t, 0), 0);
      else
	dump_unary_op ("&", t, nop);
      break;

    case INDIRECT_REF:
      if (TREE_HAS_CONSTRUCTOR (t))
	{
	  t = TREE_OPERAND (t, 0);
	  my_friendly_assert (TREE_CODE (t) == CALL_EXPR, 237);
	  dump_expr (TREE_OPERAND (t, 0), 0);
	  OB_PUTC ('(');
	  dump_expr_list (TREE_CHAIN (TREE_OPERAND (t, 1)));
	  OB_PUTC (')');
	}
      else
	{
	  if (NEXT_CODE (TREE_OPERAND (t, 0)) == REFERENCE_TYPE)
	    dump_expr (TREE_OPERAND (t, 0), nop);
	  else
	    dump_unary_op ("*", t, nop);
	}
      break;

    case NEGATE_EXPR:
    case BIT_NOT_EXPR:
    case TRUTH_NOT_EXPR:
    case PREDECREMENT_EXPR:
    case PREINCREMENT_EXPR:
      dump_unary_op (opname_tab [(int)TREE_CODE (t)], t, nop);
      break;

    case POSTDECREMENT_EXPR:
    case POSTINCREMENT_EXPR:
      OB_PUTC ('(');
      dump_expr (TREE_OPERAND (t, 0), 0);
      OB_PUTCP (opname_tab[(int)TREE_CODE (t)]);
      OB_PUTC (')');
      break;

    case NON_LVALUE_EXPR:
      /* FIXME: This is a KLUDGE workaround for a parsing problem.  There
	 should be another level of INDIRECT_REF so that I don't have to do
	 this.  */
      if (NEXT_CODE (t) == POINTER_TYPE)
	{
	  tree next = TREE_TYPE (TREE_TYPE (t));

	  while (TREE_CODE (next) == POINTER_TYPE)
	    next = TREE_TYPE (next);
	  
	  if (TREE_CODE (next) == FUNCTION_TYPE)
	    {
	      if (!nop) OB_PUTC ('(');
	      OB_PUTC ('*');
	      dump_expr (TREE_OPERAND (t, 0), 1);
	      if (!nop) OB_PUTC (')');
	      break;
	    }
	  /* else FALLTHRU */
	}
      dump_expr (TREE_OPERAND (t, 0), 0);
      break;

    case NOP_EXPR:
      dump_expr (TREE_OPERAND (t, 0), nop);
      break;

    case CONSTRUCTOR:
      OB_PUTC ('{');
      dump_expr_list (CONSTRUCTOR_ELTS (t), 0);
      OB_PUTC ('}');
      break;

    case OFFSET_REF:
      {
	tree ob = TREE_OPERAND (t, 0);
	if (TREE_CODE (ob) == NOP_EXPR
	    && TREE_OPERAND (ob, 0) == error_mark_node
	    && TREE_CODE (TREE_OPERAND (t, 1)) == FUNCTION_DECL)
	    /* A::f */
	  dump_expr (TREE_OPERAND (t, 1), 0);
	else
	  {
	    sorry ("operand of OFFSET_REF not understood");
	    goto error;
	  }
	break;
      }

    case TREE_LIST:
      if (TREE_VALUE (t) && TREE_CODE (TREE_VALUE (t)) == FUNCTION_DECL)
	{
	  OB_PUTID (DECL_NAME (TREE_VALUE (t)));
	  break;
	}
      /* else fall through */	

      /*  This list is incomplete, but should suffice for now.
	  It is very important that `sorry' does not call
	  `report_error_function'.  That could cause an infinite loop.  */
    default:
      sorry ("`%s' not supported by dump_expr",
	     tree_code_name[(int) TREE_CODE (t)]);

      /* fall through to ERROR_MARK...  */
    case ERROR_MARK:
    error:
      OB_PUTCP ("{error}");
      break;
    }
}

static void
dump_binary_op (opstring, t)
     char *opstring;
     tree t;
{
  OB_PUTC ('(');
  dump_expr (TREE_OPERAND (t, 0), 1);
  OB_PUTC (' ');
  OB_PUTCP (opstring);
  OB_PUTC (' ');
  dump_expr (TREE_OPERAND (t, 1), 1);
  OB_PUTC (')');
}

static void
dump_unary_op (opstring, t, nop)
     char *opstring;
     tree t;
     int nop;
{
  if (!nop) OB_PUTC ('(');
  OB_PUTCP (opstring);
  dump_expr (TREE_OPERAND (t, 0), 1);
  if (!nop) OB_PUTC (')');
}

char *
fndecl_as_string (cname, fndecl, print_ret_type_p)
     tree cname, fndecl;
     int print_ret_type_p;
{
  return decl_as_string (fndecl, print_ret_type_p);
}

/* Same, but handtype a _TYPE.
   Called from convert_to_reference, mangle_class_name_for_template,
   build_unary_op, and GNU_xref_decl.  */
char *
type_as_string (typ, v)
     tree typ;
     int v;
{
  OB_INIT ();

  dump_type (typ, v);

  OB_FINISH ();

  return (char *)obstack_base (&scratch_obstack);
}

char *
expr_as_string (decl, v)
     tree decl;
     int v;
{
  OB_INIT ();

  dump_expr (decl, 1);

  OB_FINISH ();

  return (char *)obstack_base (&scratch_obstack);
}

/* A cross between type_as_string and fndecl_as_string.
   Only called from substitute_nice_name.  */
char *
decl_as_string (decl, v)
     tree decl;
     int v;
{
  OB_INIT ();

  dump_decl (decl, v);

  OB_FINISH ();

  return (char *)obstack_base (&scratch_obstack);
}

char *
cp_file_of (t)
     tree t;
{
  if (TREE_CODE (t) == PARM_DECL)
    return DECL_SOURCE_FILE (DECL_CONTEXT (t));
  else if (TREE_CODE_CLASS (TREE_CODE (t)) == 't')
    return DECL_SOURCE_FILE (TYPE_NAME (t));
  else
    return DECL_SOURCE_FILE (t);
}

int
cp_line_of (t)
     tree t;
{
  int line = 0;
  if (TREE_CODE (t) == PARM_DECL)
    line = DECL_SOURCE_LINE (DECL_CONTEXT (t));
  if (TREE_CODE (t) == TYPE_DECL && DECL_ARTIFICIAL (t))
    t = TREE_TYPE (t);

  if (TREE_CODE_CLASS (TREE_CODE (t)) == 't')
    {
      if (IS_AGGR_TYPE (t))
	line = CLASSTYPE_SOURCE_LINE (t);
      else
	line = DECL_SOURCE_LINE (TYPE_NAME (t));
    }
  else
    line = DECL_SOURCE_LINE (t);

  if (line == 0)
    return lineno;

  return line;
}

char *
code_as_string (c, v)
     enum tree_code c;
     int v;
{
  return tree_code_name [c];
}

char *
language_as_string (c, v)
     enum languages c;
     int v;
{
  switch (c)
    {
    case lang_c:
      return "C";

    case lang_cplusplus:
      return "C++";

    default:
      my_friendly_abort (355);
      return 0;
    }
}

/* Return the proper printed version of a parameter to a C++ function.  */
char *
parm_as_string (p, v)
     int p, v;
{
  if (p < 0)
    return "`this'";

  sprintf (digit_buffer, "%d", p+1);
  return digit_buffer;
}

char *
op_as_string (p, v)
     enum tree_code p;
     int v;
{
  static char buf[] = "operator                ";

  if (p == 0)
    return "{unknown}";
  
  strcpy (buf + 9, opname_tab [p]);
  return buf;
}

char *
args_as_string (p, v)
     tree p;
     int v;
{
  if (p == NULL_TREE)
    return "...";

  return type_as_string (p, v);
}

char *
cv_as_string (p, v)
     tree p;
     int v;
{
  OB_INIT ();

  dump_readonly_or_volatile (p, before);

  OB_FINISH ();

  return (char *)obstack_base (&scratch_obstack);
}