static tree
compute_object_offset (tree expr, tree var)
{
  enum tree_code code = PLUS_EXPR;
  tree base, off, t;

  if (expr == var)
    return size_zero_node;

  switch (TREE_CODE (expr))
    {
    case COMPONENT_REF:
      base = compute_object_offset (TREE_OPERAND (expr, 0), var);
      if (base == error_mark_node)
	return base;

      t = TREE_OPERAND (expr, 1);
      off = size_binop (PLUS_EXPR, DECL_FIELD_OFFSET (t),
			size_int (tree_low_cst (DECL_FIELD_BIT_OFFSET (t), 1)
				  / BITS_PER_UNIT));
      break;

    case REALPART_EXPR:
    case NOP_EXPR:
    case CONVERT_EXPR:
    case VIEW_CONVERT_EXPR:
    case NON_LVALUE_EXPR:
      return compute_object_offset (TREE_OPERAND (expr, 0), var);

    case IMAGPART_EXPR:
      base = compute_object_offset (TREE_OPERAND (expr, 0), var);
      if (base == error_mark_node)
	return base;

      off = TYPE_SIZE_UNIT (TREE_TYPE (expr));
      break;

    case ARRAY_REF:
      base = compute_object_offset (TREE_OPERAND (expr, 0), var);
      if (base == error_mark_node)
	return base;

      t = TREE_OPERAND (expr, 1);
      if (TREE_CODE (t) == INTEGER_CST && tree_int_cst_sgn (t) < 0)
	{
	  code = MINUS_EXPR;
	  t = fold_build1 (NEGATE_EXPR, TREE_TYPE (t), t);
	}
      t = convert (sizetype, t);
      off = size_binop (MULT_EXPR, TYPE_SIZE_UNIT (TREE_TYPE (expr)), t);
      break;

    default:
      return error_mark_node;
    }

  return size_binop (code, base, off);
}
Exemple #2
0
static unsigned HOST_WIDE_INT
addr_object_size (struct object_size_info *osi, const_tree ptr,
		  int object_size_type)
{
  tree pt_var, pt_var_size = NULL_TREE, var_size, bytes;

  gcc_assert (TREE_CODE (ptr) == ADDR_EXPR);

  pt_var = TREE_OPERAND (ptr, 0);
  while (handled_component_p (pt_var))
    pt_var = TREE_OPERAND (pt_var, 0);

  if (pt_var
      && TREE_CODE (pt_var) == MEM_REF)
    {
      unsigned HOST_WIDE_INT sz;

      if (!osi || (object_size_type & 1) != 0
	  || TREE_CODE (TREE_OPERAND (pt_var, 0)) != SSA_NAME)
	{
	  sz = compute_builtin_object_size (TREE_OPERAND (pt_var, 0),
					    object_size_type & ~1);
	}
      else
	{
	  tree var = TREE_OPERAND (pt_var, 0);
	  if (osi->pass == 0)
	    collect_object_sizes_for (osi, var);
	  if (bitmap_bit_p (computed[object_size_type],
			    SSA_NAME_VERSION (var)))
	    sz = object_sizes[object_size_type][SSA_NAME_VERSION (var)];
	  else
	    sz = unknown[object_size_type];
	}
      if (sz != unknown[object_size_type])
	{
	  double_int dsz = double_int::from_uhwi (sz) - mem_ref_offset (pt_var);
	  if (dsz.is_negative ())
	    sz = 0;
	  else if (dsz.fits_uhwi ())
	    sz = dsz.to_uhwi ();
	  else
	    sz = unknown[object_size_type];
	}

      if (sz != unknown[object_size_type] && sz < offset_limit)
	pt_var_size = size_int (sz);
    }
  else if (pt_var
	   && DECL_P (pt_var)
	   && host_integerp (DECL_SIZE_UNIT (pt_var), 1)
	   && (unsigned HOST_WIDE_INT)
	        tree_low_cst (DECL_SIZE_UNIT (pt_var), 1) < offset_limit)
    pt_var_size = DECL_SIZE_UNIT (pt_var);
  else if (pt_var
	   && TREE_CODE (pt_var) == STRING_CST
	   && TYPE_SIZE_UNIT (TREE_TYPE (pt_var))
	   && host_integerp (TYPE_SIZE_UNIT (TREE_TYPE (pt_var)), 1)
	   && (unsigned HOST_WIDE_INT)
	      tree_low_cst (TYPE_SIZE_UNIT (TREE_TYPE (pt_var)), 1)
	      < offset_limit)
    pt_var_size = TYPE_SIZE_UNIT (TREE_TYPE (pt_var));
  else
    return unknown[object_size_type];

  if (pt_var != TREE_OPERAND (ptr, 0))
    {
      tree var;

      if (object_size_type & 1)
	{
	  var = TREE_OPERAND (ptr, 0);

	  while (var != pt_var
		 && TREE_CODE (var) != BIT_FIELD_REF
		 && TREE_CODE (var) != COMPONENT_REF
		 && TREE_CODE (var) != ARRAY_REF
		 && TREE_CODE (var) != ARRAY_RANGE_REF
		 && TREE_CODE (var) != REALPART_EXPR
		 && TREE_CODE (var) != IMAGPART_EXPR)
	    var = TREE_OPERAND (var, 0);
	  if (var != pt_var && TREE_CODE (var) == ARRAY_REF)
	    var = TREE_OPERAND (var, 0);
	  if (! TYPE_SIZE_UNIT (TREE_TYPE (var))
	      || ! host_integerp (TYPE_SIZE_UNIT (TREE_TYPE (var)), 1)
	      || (pt_var_size
		  && tree_int_cst_lt (pt_var_size,
				      TYPE_SIZE_UNIT (TREE_TYPE (var)))))
	    var = pt_var;
	  else if (var != pt_var && TREE_CODE (pt_var) == MEM_REF)
	    {
	      tree v = var;
	      /* For &X->fld, compute object size only if fld isn't the last
		 field, as struct { int i; char c[1]; } is often used instead
		 of flexible array member.  */
	      while (v && v != pt_var)
		switch (TREE_CODE (v))
		  {
		  case ARRAY_REF:
		    if (TYPE_SIZE_UNIT (TREE_TYPE (TREE_OPERAND (v, 0)))
			&& TREE_CODE (TREE_OPERAND (v, 1)) == INTEGER_CST)
		      {
			tree domain
			  = TYPE_DOMAIN (TREE_TYPE (TREE_OPERAND (v, 0)));
			if (domain
			    && TYPE_MAX_VALUE (domain)
			    && TREE_CODE (TYPE_MAX_VALUE (domain))
			       == INTEGER_CST
			    && tree_int_cst_lt (TREE_OPERAND (v, 1),
						TYPE_MAX_VALUE (domain)))
			  {
			    v = NULL_TREE;
			    break;
			  }
		      }
		    v = TREE_OPERAND (v, 0);
		    break;
		  case REALPART_EXPR:
		  case IMAGPART_EXPR:
		    v = NULL_TREE;
		    break;
		  case COMPONENT_REF:
		    if (TREE_CODE (TREE_TYPE (v)) != ARRAY_TYPE)
		      {
			v = NULL_TREE;
			break;
		      }
		    while (v != pt_var && TREE_CODE (v) == COMPONENT_REF)
		      if (TREE_CODE (TREE_TYPE (TREE_OPERAND (v, 0)))
			  != UNION_TYPE
			  && TREE_CODE (TREE_TYPE (TREE_OPERAND (v, 0)))
			  != QUAL_UNION_TYPE)
			break;
		      else
			v = TREE_OPERAND (v, 0);
		    if (TREE_CODE (v) == COMPONENT_REF
			&& TREE_CODE (TREE_TYPE (TREE_OPERAND (v, 0)))
			   == RECORD_TYPE)
		      {
			tree fld_chain = DECL_CHAIN (TREE_OPERAND (v, 1));
			for (; fld_chain; fld_chain = DECL_CHAIN (fld_chain))
			  if (TREE_CODE (fld_chain) == FIELD_DECL)
			    break;

			if (fld_chain)
			  {
			    v = NULL_TREE;
			    break;
			  }
			v = TREE_OPERAND (v, 0);
		      }
		    while (v != pt_var && TREE_CODE (v) == COMPONENT_REF)
		      if (TREE_CODE (TREE_TYPE (TREE_OPERAND (v, 0)))
			  != UNION_TYPE
			  && TREE_CODE (TREE_TYPE (TREE_OPERAND (v, 0)))
			  != QUAL_UNION_TYPE)
			break;
		      else
			v = TREE_OPERAND (v, 0);
		    if (v != pt_var)
		      v = NULL_TREE;
		    else
		      v = pt_var;
		    break;
		  default:
		    v = pt_var;
		    break;
		  }
	      if (v == pt_var)
		var = pt_var;
	    }
	}
      else
	var = pt_var;

      if (var != pt_var)
	var_size = TYPE_SIZE_UNIT (TREE_TYPE (var));
      else if (!pt_var_size)
	return unknown[object_size_type];
      else
	var_size = pt_var_size;
      bytes = compute_object_offset (TREE_OPERAND (ptr, 0), var);
      if (bytes != error_mark_node)
	{
	  if (TREE_CODE (bytes) == INTEGER_CST
	      && tree_int_cst_lt (var_size, bytes))
	    bytes = size_zero_node;
	  else
	    bytes = size_binop (MINUS_EXPR, var_size, bytes);
	}
      if (var != pt_var
	  && pt_var_size
	  && TREE_CODE (pt_var) == MEM_REF
	  && bytes != error_mark_node)
	{
	  tree bytes2 = compute_object_offset (TREE_OPERAND (ptr, 0), pt_var);
	  if (bytes2 != error_mark_node)
	    {
	      if (TREE_CODE (bytes2) == INTEGER_CST
		  && tree_int_cst_lt (pt_var_size, bytes2))
		bytes2 = size_zero_node;
	      else
		bytes2 = size_binop (MINUS_EXPR, pt_var_size, bytes2);
	      bytes = size_binop (MIN_EXPR, bytes, bytes2);
	    }
	}
    }
  else if (!pt_var_size)
    return unknown[object_size_type];
  else
    bytes = pt_var_size;

  if (host_integerp (bytes, 1))
    return tree_low_cst (bytes, 1);

  return unknown[object_size_type];
}
static unsigned HOST_WIDE_INT
addr_object_size (tree ptr, int object_size_type)
{
  tree pt_var;

  gcc_assert (TREE_CODE (ptr) == ADDR_EXPR);

  pt_var = TREE_OPERAND (ptr, 0);
  if (REFERENCE_CLASS_P (pt_var))
    pt_var = get_base_address (pt_var);

  if (pt_var
      && (SSA_VAR_P (pt_var) || TREE_CODE (pt_var) == STRING_CST)
      && TYPE_SIZE_UNIT (TREE_TYPE (pt_var))
      && host_integerp (TYPE_SIZE_UNIT (TREE_TYPE (pt_var)), 1)
      && (unsigned HOST_WIDE_INT)
	 tree_low_cst (TYPE_SIZE_UNIT (TREE_TYPE (pt_var)), 1) < offset_limit)
    {
      tree bytes;

      if (pt_var != TREE_OPERAND (ptr, 0))
	{
	  tree var;

	  if (object_size_type & 1)
	    {
	      var = TREE_OPERAND (ptr, 0);

	      while (var != pt_var
		      && TREE_CODE (var) != BIT_FIELD_REF
		      && TREE_CODE (var) != COMPONENT_REF
		      && TREE_CODE (var) != ARRAY_REF
		      && TREE_CODE (var) != ARRAY_RANGE_REF
		      && TREE_CODE (var) != REALPART_EXPR
		      && TREE_CODE (var) != IMAGPART_EXPR)
		var = TREE_OPERAND (var, 0);
	      if (var != pt_var && TREE_CODE (var) == ARRAY_REF)
		var = TREE_OPERAND (var, 0);
	      if (! TYPE_SIZE_UNIT (TREE_TYPE (var))
		  || ! host_integerp (TYPE_SIZE_UNIT (TREE_TYPE (var)), 1)
		  || tree_int_cst_lt (TYPE_SIZE_UNIT (TREE_TYPE (pt_var)),
				      TYPE_SIZE_UNIT (TREE_TYPE (var))))
		var = pt_var;
	    }
	  else
	    var = pt_var;

	  bytes = compute_object_offset (TREE_OPERAND (ptr, 0), var);
	  if (bytes != error_mark_node)
	    {
	      if (TREE_CODE (bytes) == INTEGER_CST
		  && tree_int_cst_lt (TYPE_SIZE_UNIT (TREE_TYPE (var)), bytes))
		bytes = size_zero_node;
	      else
		bytes = size_binop (MINUS_EXPR,
				    TYPE_SIZE_UNIT (TREE_TYPE (var)), bytes);
	    }
	}
      else
	bytes = TYPE_SIZE_UNIT (TREE_TYPE (pt_var));

      if (host_integerp (bytes, 1))
	return tree_low_cst (bytes, 1);
    }

  return unknown[object_size_type];
}
Exemple #4
0
static tree
compute_object_offset (const_tree expr, const_tree var)
{
  enum tree_code code = PLUS_EXPR;
  tree base, off, t;

  if (expr == var)
    return size_zero_node;

  switch (TREE_CODE (expr))
    {
    case COMPONENT_REF:
      base = compute_object_offset (TREE_OPERAND (expr, 0), var);
      if (base == error_mark_node)
	return base;

      t = TREE_OPERAND (expr, 1);
      off = size_binop (PLUS_EXPR, DECL_FIELD_OFFSET (t),
			size_int (tree_to_uhwi (DECL_FIELD_BIT_OFFSET (t))
				  / BITS_PER_UNIT));
      break;

    case REALPART_EXPR:
    CASE_CONVERT:
    case VIEW_CONVERT_EXPR:
    case NON_LVALUE_EXPR:
      return compute_object_offset (TREE_OPERAND (expr, 0), var);

    case IMAGPART_EXPR:
      base = compute_object_offset (TREE_OPERAND (expr, 0), var);
      if (base == error_mark_node)
	return base;

      off = TYPE_SIZE_UNIT (TREE_TYPE (expr));
      break;

    case ARRAY_REF:
      base = compute_object_offset (TREE_OPERAND (expr, 0), var);
      if (base == error_mark_node)
	return base;

      t = TREE_OPERAND (expr, 1);
      tree low_bound, unit_size;
      low_bound = array_ref_low_bound (CONST_CAST_TREE (expr));
      unit_size = array_ref_element_size (CONST_CAST_TREE (expr));
      if (! integer_zerop (low_bound))
	t = fold_build2 (MINUS_EXPR, TREE_TYPE (t), t, low_bound);
      if (TREE_CODE (t) == INTEGER_CST && tree_int_cst_sgn (t) < 0)
	{
	  code = MINUS_EXPR;
	  t = fold_build1 (NEGATE_EXPR, TREE_TYPE (t), t);
	}
      t = fold_convert (sizetype, t);
      off = size_binop (MULT_EXPR, unit_size, t);
      break;

    case MEM_REF:
      gcc_assert (TREE_CODE (TREE_OPERAND (expr, 0)) == ADDR_EXPR);
      return wide_int_to_tree (sizetype, mem_ref_offset (expr));

    default:
      return error_mark_node;
    }

  return size_binop (code, base, off);
}