예제 #1
0
파일: expprint.c 프로젝트: 5kg/gdb
void
print_expression (struct expression *exp, struct ui_file *stream)
{
  int pc = 0;

  print_subexp (exp, &pc, stream, PREC_NULL);
}
예제 #2
0
/* Standard implementation of print_subexp for use in language_defn
   vectors.  */
void
print_subexp_standard (struct expression *exp, int *pos,
		       struct ui_file *stream, enum precedence prec)
{
  unsigned tem;
  const struct op_print *op_print_tab;
  int pc;
  unsigned nargs;
  char *op_str;
  int assign_modify = 0;
  enum exp_opcode opcode;
  enum precedence myprec = PREC_NULL;
  /* Set to 1 for a right-associative operator.  */
  int assoc = 0;
  struct value *val;
  char *tempstr = NULL;

  op_print_tab = exp->language_defn->la_op_print_tab;
  pc = (*pos)++;
  opcode = exp->elts[pc].opcode;
  switch (opcode)
    {
      /* Common ops */

    case OP_SCOPE:
      myprec = PREC_PREFIX;
      assoc = 0;
      fputs_filtered (type_name_no_tag (exp->elts[pc + 1].type), stream);
      fputs_filtered ("::", stream);
      nargs = longest_to_int (exp->elts[pc + 2].longconst);
      (*pos) += 4 + BYTES_TO_EXP_ELEM (nargs + 1);
      fputs_filtered (&exp->elts[pc + 3].string, stream);
      return;

    case OP_LONG:
      (*pos) += 3;
      value_print (value_from_longest (exp->elts[pc + 1].type,
				       exp->elts[pc + 2].longconst),
		   stream, 0, Val_no_prettyprint);
      return;

    case OP_DOUBLE:
      (*pos) += 3;
      value_print (value_from_double (exp->elts[pc + 1].type,
				      exp->elts[pc + 2].doubleconst),
		   stream, 0, Val_no_prettyprint);
      return;

    case OP_VAR_VALUE:
      {
	struct block *b;
	(*pos) += 3;
	b = exp->elts[pc + 1].block;
	if (b != NULL
	    && BLOCK_FUNCTION (b) != NULL
	    && SYMBOL_PRINT_NAME (BLOCK_FUNCTION (b)) != NULL)
	  {
	    fputs_filtered (SYMBOL_PRINT_NAME (BLOCK_FUNCTION (b)), stream);
	    fputs_filtered ("::", stream);
	  }
	fputs_filtered (SYMBOL_PRINT_NAME (exp->elts[pc + 2].symbol), stream);
      }
      return;

    case OP_LAST:
      (*pos) += 2;
      fprintf_filtered (stream, "$%d",
			longest_to_int (exp->elts[pc + 1].longconst));
      return;

    case OP_REGISTER:
      {
	int regnum = longest_to_int (exp->elts[pc + 1].longconst);
	const char *name = user_reg_map_regnum_to_name (current_gdbarch,
							regnum);
	(*pos) += 2;
	fprintf_filtered (stream, "$%s", name);
	return;
      }

    case OP_BOOL:
      (*pos) += 2;
      fprintf_filtered (stream, "%s",
			longest_to_int (exp->elts[pc + 1].longconst)
			? "TRUE" : "FALSE");
      return;

    case OP_INTERNALVAR:
      (*pos) += 2;
      fprintf_filtered (stream, "$%s",
			internalvar_name (exp->elts[pc + 1].internalvar));
      return;

    case OP_FUNCALL:
      (*pos) += 2;
      nargs = longest_to_int (exp->elts[pc + 1].longconst);
      print_subexp (exp, pos, stream, PREC_SUFFIX);
      fputs_filtered (" (", stream);
      for (tem = 0; tem < nargs; tem++)
	{
	  if (tem != 0)
	    fputs_filtered (", ", stream);
	  print_subexp (exp, pos, stream, PREC_ABOVE_COMMA);
	}
      fputs_filtered (")", stream);
      return;

    case OP_NAME:
    case OP_EXPRSTRING:
      nargs = longest_to_int (exp->elts[pc + 1].longconst);
      (*pos) += 3 + BYTES_TO_EXP_ELEM (nargs + 1);
      fputs_filtered (&exp->elts[pc + 2].string, stream);
      return;

    case OP_STRING:
      nargs = longest_to_int (exp->elts[pc + 1].longconst);
      (*pos) += 3 + BYTES_TO_EXP_ELEM (nargs + 1);
      /* LA_PRINT_STRING will print using the current repeat count threshold.
         If necessary, we can temporarily set it to zero, or pass it as an
         additional parameter to LA_PRINT_STRING.  -fnf */
      LA_PRINT_STRING (stream, &exp->elts[pc + 2].string, nargs, 1, 0);
      return;

    case OP_BITSTRING:
      nargs = longest_to_int (exp->elts[pc + 1].longconst);
      (*pos)
	+= 3 + BYTES_TO_EXP_ELEM ((nargs + HOST_CHAR_BIT - 1) / HOST_CHAR_BIT);
      fprintf_unfiltered (stream, "B'<unimplemented>'");
      return;

    case OP_OBJC_NSSTRING:	/* Objective-C Foundation Class NSString constant.  */
      nargs = longest_to_int (exp->elts[pc + 1].longconst);
      (*pos) += 3 + BYTES_TO_EXP_ELEM (nargs + 1);
      fputs_filtered ("@\"", stream);
      LA_PRINT_STRING (stream, &exp->elts[pc + 2].string, nargs, 1, 0);
      fputs_filtered ("\"", stream);
      return;

    case OP_OBJC_MSGCALL:
      {			/* Objective C message (method) call.  */
	char *selector;
	(*pos) += 3;
	nargs = longest_to_int (exp->elts[pc + 2].longconst);
	fprintf_unfiltered (stream, "[");
	print_subexp (exp, pos, stream, PREC_SUFFIX);
	if (0 == target_read_string (exp->elts[pc + 1].longconst,
				     &selector, 1024, NULL))
	  {
	    error (_("bad selector"));
	    return;
	  }
	if (nargs)
	  {
	    char *s, *nextS;
	    s = alloca (strlen (selector) + 1);
	    strcpy (s, selector);
	    for (tem = 0; tem < nargs; tem++)
	      {
		nextS = strchr (s, ':');
		*nextS = '\0';
		fprintf_unfiltered (stream, " %s: ", s);
		s = nextS + 1;
		print_subexp (exp, pos, stream, PREC_ABOVE_COMMA);
	      }
	  }
	else
	  {
	    fprintf_unfiltered (stream, " %s", selector);
	  }
	fprintf_unfiltered (stream, "]");
	/* "selector" was malloc'd by target_read_string. Free it.  */
	xfree (selector);
	return;
      }

    case OP_ARRAY:
      (*pos) += 3;
      nargs = longest_to_int (exp->elts[pc + 2].longconst);
      nargs -= longest_to_int (exp->elts[pc + 1].longconst);
      nargs++;
      tem = 0;
      if (exp->elts[pc + 4].opcode == OP_LONG
	  && exp->elts[pc + 5].type == builtin_type_char
	  && exp->language_defn->la_language == language_c)
	{
	  /* Attempt to print C character arrays using string syntax.
	     Walk through the args, picking up one character from each
	     of the OP_LONG expression elements.  If any array element
	     does not match our expection of what we should find for
	     a simple string, revert back to array printing.  Note that
	     the last expression element is an explicit null terminator
	     byte, which doesn't get printed. */
	  tempstr = alloca (nargs);
	  pc += 4;
	  while (tem < nargs)
	    {
	      if (exp->elts[pc].opcode != OP_LONG
		  || exp->elts[pc + 1].type != builtin_type_char)
		{
		  /* Not a simple array of char, use regular array printing. */
		  tem = 0;
		  break;
		}
	      else
		{
		  tempstr[tem++] =
		    longest_to_int (exp->elts[pc + 2].longconst);
		  pc += 4;
		}
	    }
	}
      if (tem > 0)
	{
	  LA_PRINT_STRING (stream, tempstr, nargs - 1, 1, 0);
	  (*pos) = pc;
	}
      else
	{
	  fputs_filtered (" {", stream);
	  for (tem = 0; tem < nargs; tem++)
	    {
	      if (tem != 0)
		{
		  fputs_filtered (", ", stream);
		}
	      print_subexp (exp, pos, stream, PREC_ABOVE_COMMA);
	    }
	  fputs_filtered ("}", stream);
	}
      return;

    case OP_LABELED:
      tem = longest_to_int (exp->elts[pc + 1].longconst);
      (*pos) += 3 + BYTES_TO_EXP_ELEM (tem + 1);
      /* Gcc support both these syntaxes.  Unsure which is preferred.  */
#if 1
      fputs_filtered (&exp->elts[pc + 2].string, stream);
      fputs_filtered (": ", stream);
#else
      fputs_filtered (".", stream);
      fputs_filtered (&exp->elts[pc + 2].string, stream);
      fputs_filtered ("=", stream);
#endif
      print_subexp (exp, pos, stream, PREC_SUFFIX);
      return;

    case TERNOP_COND:
      if ((int) prec > (int) PREC_COMMA)
	fputs_filtered ("(", stream);
      /* Print the subexpressions, forcing parentheses
         around any binary operations within them.
         This is more parentheses than are strictly necessary,
         but it looks clearer.  */
      print_subexp (exp, pos, stream, PREC_HYPER);
      fputs_filtered (" ? ", stream);
      print_subexp (exp, pos, stream, PREC_HYPER);
      fputs_filtered (" : ", stream);
      print_subexp (exp, pos, stream, PREC_HYPER);
      if ((int) prec > (int) PREC_COMMA)
	fputs_filtered (")", stream);
      return;

    case TERNOP_SLICE:
    case TERNOP_SLICE_COUNT:
      print_subexp (exp, pos, stream, PREC_SUFFIX);
      fputs_filtered ("(", stream);
      print_subexp (exp, pos, stream, PREC_ABOVE_COMMA);
      fputs_filtered (opcode == TERNOP_SLICE ? " : " : " UP ", stream);
      print_subexp (exp, pos, stream, PREC_ABOVE_COMMA);
      fputs_filtered (")", stream);
      return;

    case STRUCTOP_STRUCT:
      tem = longest_to_int (exp->elts[pc + 1].longconst);
      (*pos) += 3 + BYTES_TO_EXP_ELEM (tem + 1);
      print_subexp (exp, pos, stream, PREC_SUFFIX);
      fputs_filtered (".", stream);
      fputs_filtered (&exp->elts[pc + 2].string, stream);
      return;

      /* Will not occur for Modula-2 */
    case STRUCTOP_PTR:
      tem = longest_to_int (exp->elts[pc + 1].longconst);
      (*pos) += 3 + BYTES_TO_EXP_ELEM (tem + 1);
      print_subexp (exp, pos, stream, PREC_SUFFIX);
      fputs_filtered ("->", stream);
      fputs_filtered (&exp->elts[pc + 2].string, stream);
      return;

    case BINOP_SUBSCRIPT:
      print_subexp (exp, pos, stream, PREC_SUFFIX);
      fputs_filtered ("[", stream);
      print_subexp (exp, pos, stream, PREC_ABOVE_COMMA);
      fputs_filtered ("]", stream);
      return;

    case UNOP_POSTINCREMENT:
      print_subexp (exp, pos, stream, PREC_SUFFIX);
      fputs_filtered ("++", stream);
      return;

    case UNOP_POSTDECREMENT:
      print_subexp (exp, pos, stream, PREC_SUFFIX);
      fputs_filtered ("--", stream);
      return;

    case UNOP_CAST:
      (*pos) += 2;
      if ((int) prec > (int) PREC_PREFIX)
	fputs_filtered ("(", stream);
      fputs_filtered ("(", stream);
      type_print (exp->elts[pc + 1].type, "", stream, 0);
      fputs_filtered (") ", stream);
      print_subexp (exp, pos, stream, PREC_PREFIX);
      if ((int) prec > (int) PREC_PREFIX)
	fputs_filtered (")", stream);
      return;

    case UNOP_MEMVAL:
      (*pos) += 2;
      if ((int) prec > (int) PREC_PREFIX)
	fputs_filtered ("(", stream);
      if (TYPE_CODE (exp->elts[pc + 1].type) == TYPE_CODE_FUNC &&
	  exp->elts[pc + 3].opcode == OP_LONG)
	{
	  /* We have a minimal symbol fn, probably.  It's encoded
	     as a UNOP_MEMVAL (function-type) of an OP_LONG (int, address).
	     Swallow the OP_LONG (including both its opcodes); ignore
	     its type; print the value in the type of the MEMVAL.  */
	  (*pos) += 4;
	  val = value_at_lazy (exp->elts[pc + 1].type,
			       (CORE_ADDR) exp->elts[pc + 5].longconst);
	  value_print (val, stream, 0, Val_no_prettyprint);
	}
      else
	{
	  fputs_filtered ("{", stream);
	  type_print (exp->elts[pc + 1].type, "", stream, 0);
	  fputs_filtered ("} ", stream);
	  print_subexp (exp, pos, stream, PREC_PREFIX);
	}
      if ((int) prec > (int) PREC_PREFIX)
	fputs_filtered (")", stream);
      return;

    case BINOP_ASSIGN_MODIFY:
      opcode = exp->elts[pc + 1].opcode;
      (*pos) += 2;
      myprec = PREC_ASSIGN;
      assoc = 1;
      assign_modify = 1;
      op_str = "???";
      for (tem = 0; op_print_tab[tem].opcode != OP_NULL; tem++)
	if (op_print_tab[tem].opcode == opcode)
	  {
	    op_str = op_print_tab[tem].string;
	    break;
	  }
      if (op_print_tab[tem].opcode != opcode)
	/* Not found; don't try to keep going because we don't know how
	   to interpret further elements.  */
	error (_("Invalid expression"));
      break;

      /* C++ ops */

    case OP_THIS:
      ++(*pos);
      fputs_filtered ("this", stream);
      return;

      /* Objective-C ops */

    case OP_OBJC_SELF:
      ++(*pos);
      fputs_filtered ("self", stream);	/* The ObjC equivalent of "this".  */
      return;

      /* Modula-2 ops */

    case MULTI_SUBSCRIPT:
      (*pos) += 2;
      nargs = longest_to_int (exp->elts[pc + 1].longconst);
      print_subexp (exp, pos, stream, PREC_SUFFIX);
      fprintf_unfiltered (stream, " [");
      for (tem = 0; tem < nargs; tem++)
	{
	  if (tem != 0)
	    fprintf_unfiltered (stream, ", ");
	  print_subexp (exp, pos, stream, PREC_ABOVE_COMMA);
	}
      fprintf_unfiltered (stream, "]");
      return;

    case BINOP_VAL:
      (*pos) += 2;
      fprintf_unfiltered (stream, "VAL(");
      type_print (exp->elts[pc + 1].type, "", stream, 0);
      fprintf_unfiltered (stream, ",");
      print_subexp (exp, pos, stream, PREC_PREFIX);
      fprintf_unfiltered (stream, ")");
      return;

    case BINOP_INCL:
    case BINOP_EXCL:
      error (_("print_subexp:  Not implemented."));

      /* Default ops */

    default:
      op_str = "???";
      for (tem = 0; op_print_tab[tem].opcode != OP_NULL; tem++)
	if (op_print_tab[tem].opcode == opcode)
	  {
	    op_str = op_print_tab[tem].string;
	    myprec = op_print_tab[tem].precedence;
	    assoc = op_print_tab[tem].right_assoc;
	    break;
	  }
      if (op_print_tab[tem].opcode != opcode)
	/* Not found; don't try to keep going because we don't know how
	   to interpret further elements.  For example, this happens
	   if opcode is OP_TYPE.  */
	error (_("Invalid expression"));
    }

  /* Note that PREC_BUILTIN will always emit parentheses. */
  if ((int) myprec < (int) prec)
    fputs_filtered ("(", stream);
  if ((int) opcode > (int) BINOP_END)
    {
      if (assoc)
	{
	  /* Unary postfix operator.  */
	  print_subexp (exp, pos, stream, PREC_SUFFIX);
	  fputs_filtered (op_str, stream);
	}
      else
	{
	  /* Unary prefix operator.  */
	  fputs_filtered (op_str, stream);
	  if (myprec == PREC_BUILTIN_FUNCTION)
	    fputs_filtered ("(", stream);
	  print_subexp (exp, pos, stream, PREC_PREFIX);
	  if (myprec == PREC_BUILTIN_FUNCTION)
	    fputs_filtered (")", stream);
	}
    }
  else
    {
      /* Binary operator.  */
      /* Print left operand.
         If operator is right-associative,
         increment precedence for this operand.  */
      print_subexp (exp, pos, stream,
		    (enum precedence) ((int) myprec + assoc));
      /* Print the operator itself.  */
      if (assign_modify)
	fprintf_filtered (stream, " %s= ", op_str);
      else if (op_str[0] == ',')
	fprintf_filtered (stream, "%s ", op_str);
      else
	fprintf_filtered (stream, " %s ", op_str);
      /* Print right operand.
         If operator is left-associative,
         increment precedence for this operand.  */
      print_subexp (exp, pos, stream,
		    (enum precedence) ((int) myprec + !assoc));
    }

  if ((int) myprec < (int) prec)
    fputs_filtered (")", stream);
}