예제 #1
0
static tree
declare_library_fn (const char *name, tree rtype, tree ptype,
		    int ecf, int tm_ecf)
{
  tree ident = get_identifier (name);
  tree res = get_global_binding (ident);
  if (!res)
    {
      tree type = build_function_type_list (rtype, ptype, NULL_TREE);
      tree except = ecf & ECF_NOTHROW ? empty_except_spec : NULL_TREE;
      res = push_library_fn (ident, type, except, ecf);
      if (tm_ecf && flag_tm)
	{
	  char *tm_name = concat ("_ITM_", name + 2, NULL_TREE);
	  tree tm_ident = get_identifier (tm_name);
	  free (tm_name);
	  tree tm_fn = get_global_binding (tm_ident);
	  if (!tm_fn)
	    tm_fn = push_library_fn (tm_ident, type, except, ecf | tm_ecf);
	  record_tm_replacement (res, tm_fn);
	}
    }
  return res;
}
예제 #2
0
tree
build_throw (tree exp)
{
  if (exp == error_mark_node)
    return exp;

  if (processing_template_decl)
    {
      if (cfun)
	current_function_returns_abnormally = 1;
      exp = build_min (THROW_EXPR, void_type_node, exp);
      SET_EXPR_LOCATION (exp, input_location);
      return exp;
    }

  if (exp && null_node_p (exp))
    warning (0, "throwing NULL, which has integral, not pointer type");

  if (exp != NULL_TREE)
    {
      if (!is_admissible_throw_operand_or_catch_parameter (exp, true))
	return error_mark_node;
    }

  if (! doing_eh ())
    return error_mark_node;

  if (exp)
    {
      tree throw_type;
      tree temp_type;
      tree cleanup;
      tree object, ptr;
      tree tmp;
      tree allocate_expr;

      /* The CLEANUP_TYPE is the internal type of a destructor.  */
      if (!cleanup_type)
	{
	  tmp = build_function_type_list (void_type_node,
					  ptr_type_node, NULL_TREE);
	  cleanup_type = build_pointer_type (tmp);
	}

      if (!throw_fn)
	{
	  tree name = get_identifier ("__cxa_throw");
	  throw_fn = get_global_binding (name);
	  if (!throw_fn)
	    {
	      /* Declare void __cxa_throw (void*, void*, void (*)(void*)).  */
	      /* ??? Second argument is supposed to be "std::type_info*".  */
	      tmp = build_function_type_list (void_type_node,
					      ptr_type_node, ptr_type_node,
					      cleanup_type, NULL_TREE);
	      throw_fn = push_throw_library_fn (name, tmp);

	      if (flag_tm)
		{
		  tree itm_name = get_identifier ("_ITM_cxa_throw");
		  tree itm_fn = get_global_binding (itm_name);
		  if (!itm_fn)
		    itm_fn = push_throw_library_fn (itm_name, tmp);
		  apply_tm_attr (itm_fn, get_identifier ("transaction_pure"));
		  record_tm_replacement (throw_fn, itm_fn);
		}
	    }
	}

      /* [except.throw]

	 A throw-expression initializes a temporary object, the type
	 of which is determined by removing any top-level
	 cv-qualifiers from the static type of the operand of throw
	 and adjusting the type from "array of T" or "function return
	 T" to "pointer to T" or "pointer to function returning T"
	 respectively.  */
      temp_type = is_bitfield_expr_with_lowered_type (exp);
      if (!temp_type)
	temp_type = cv_unqualified (type_decays_to (TREE_TYPE (exp)));

      /* OK, this is kind of wacky.  The standard says that we call
	 terminate when the exception handling mechanism, after
	 completing evaluation of the expression to be thrown but
	 before the exception is caught (_except.throw_), calls a
	 user function that exits via an uncaught exception.

	 So we have to protect the actual initialization of the
	 exception object with terminate(), but evaluate the
	 expression first.  Since there could be temps in the
	 expression, we need to handle that, too.  We also expand
	 the call to __cxa_allocate_exception first (which doesn't
	 matter, since it can't throw).  */

      /* Allocate the space for the exception.  */
      allocate_expr = do_allocate_exception (temp_type);
      allocate_expr = get_target_expr (allocate_expr);
      ptr = TARGET_EXPR_SLOT (allocate_expr);
      TARGET_EXPR_CLEANUP (allocate_expr) = do_free_exception (ptr);
      CLEANUP_EH_ONLY (allocate_expr) = 1;

      object = build_nop (build_pointer_type (temp_type), ptr);
      object = cp_build_fold_indirect_ref (object);

      /* And initialize the exception object.  */
      if (CLASS_TYPE_P (temp_type))
	{
	  int flags = LOOKUP_NORMAL | LOOKUP_ONLYCONVERTING;
	  vec<tree, va_gc> *exp_vec;
	  bool converted = false;

	  /* Under C++0x [12.8/16 class.copy], a thrown lvalue is sometimes
	     treated as an rvalue for the purposes of overload resolution
	     to favor move constructors over copy constructors.  */
	  if (/* Must be a local, automatic variable.  */
	      VAR_P (exp)
	      && DECL_CONTEXT (exp) == current_function_decl
	      && ! TREE_STATIC (exp)
	      /* The variable must not have the `volatile' qualifier.  */
	      && !(cp_type_quals (TREE_TYPE (exp)) & TYPE_QUAL_VOLATILE))
	    {
	      tree moved = move (exp);
	      exp_vec = make_tree_vector_single (moved);
	      moved = (build_special_member_call
		       (object, complete_ctor_identifier, &exp_vec,
			TREE_TYPE (object), flags|LOOKUP_PREFER_RVALUE,
			tf_none));
	      release_tree_vector (exp_vec);
	      if (moved != error_mark_node)
		{
		  exp = moved;
		  converted = true;
		}
	    }

	  /* Call the copy constructor.  */
	  if (!converted)
	    {
	      exp_vec = make_tree_vector_single (exp);
	      exp = (build_special_member_call
		     (object, complete_ctor_identifier, &exp_vec,
		      TREE_TYPE (object), flags, tf_warning_or_error));
	      release_tree_vector (exp_vec);
	    }

	  if (exp == error_mark_node)
	    {
	      error ("  in thrown expression");
	      return error_mark_node;
	    }
	}
      else
	{
	  tmp = decay_conversion (exp, tf_warning_or_error);
	  if (tmp == error_mark_node)
	    return error_mark_node;
	  exp = build2 (INIT_EXPR, temp_type, object, tmp);
	}

      /* Mark any cleanups from the initialization as MUST_NOT_THROW, since
	 they are run after the exception object is initialized.  */
      cp_walk_tree_without_duplicates (&exp, wrap_cleanups_r, 0);

      /* Prepend the allocation.  */
      exp = build2 (COMPOUND_EXPR, TREE_TYPE (exp), allocate_expr, exp);

      /* Force all the cleanups to be evaluated here so that we don't have
	 to do them during unwinding.  */
      exp = build1 (CLEANUP_POINT_EXPR, void_type_node, exp);

      throw_type = build_eh_type_type (prepare_eh_type (TREE_TYPE (object)));

      cleanup = NULL_TREE;
      if (type_build_dtor_call (TREE_TYPE (object)))
	{
	  tree dtor_fn = lookup_fnfields (TYPE_BINFO (TREE_TYPE (object)),
					  complete_dtor_identifier, 0);
	  dtor_fn = BASELINK_FUNCTIONS (dtor_fn);
	  mark_used (dtor_fn);
	  if (TYPE_HAS_NONTRIVIAL_DESTRUCTOR (TREE_TYPE (object)))
	    {
	      cxx_mark_addressable (dtor_fn);
	      /* Pretend it's a normal function.  */
	      cleanup = build1 (ADDR_EXPR, cleanup_type, dtor_fn);
	    }
	}
      if (cleanup == NULL_TREE)
	cleanup = build_int_cst (cleanup_type, 0);

      /* ??? Indicate that this function call throws throw_type.  */
      tmp = cp_build_function_call_nary (throw_fn, tf_warning_or_error,
					 ptr, throw_type, cleanup, NULL_TREE);

      /* Tack on the initialization stuff.  */
      exp = build2 (COMPOUND_EXPR, TREE_TYPE (tmp), exp, tmp);
    }
  else
    {
      /* Rethrow current exception.  */
      if (!rethrow_fn)
	{
	  tree name = get_identifier ("__cxa_rethrow");
	  rethrow_fn = get_global_binding (name);
	  if (!rethrow_fn)
	    /* Declare void __cxa_rethrow (void).  */
	    rethrow_fn = push_throw_library_fn
	      (name, build_function_type_list (void_type_node, NULL_TREE));

	  if (flag_tm)
	    apply_tm_attr (rethrow_fn, get_identifier ("transaction_pure"));
	}

      /* ??? Indicate that this function call allows exceptions of the type
	 of the enclosing catch block (if known).  */
      exp = cp_build_function_call_vec (rethrow_fn, NULL, tf_warning_or_error);
    }

  exp = build1 (THROW_EXPR, void_type_node, exp);
  SET_EXPR_LOCATION (exp, input_location);

  return exp;
}
예제 #3
0
tree
identifier_global_value (tree name)
{
  return get_global_binding (name);
}