423 lines
12 KiB
C
423 lines
12 KiB
C
/* Functions dealing with attribute handling, used by most front ends.
|
||
Copyright (C) 1992, 1993, 1994, 1995, 1996, 1997, 1998, 1999, 2000, 2001,
|
||
2002, 2003 Free Software Foundation, Inc.
|
||
|
||
This file is part of GCC.
|
||
|
||
GCC is free software; you can redistribute it and/or modify it under
|
||
the terms of the GNU General Public License as published by the Free
|
||
Software Foundation; either version 2, or (at your option) any later
|
||
version.
|
||
|
||
GCC is distributed in the hope that it will be useful, but WITHOUT ANY
|
||
WARRANTY; without even the implied warranty of MERCHANTABILITY or
|
||
FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License
|
||
for more details.
|
||
|
||
You should have received a copy of the GNU General Public License
|
||
along with GCC; see the file COPYING. If not, write to the Free
|
||
Software Foundation, 59 Temple Place - Suite 330, Boston, MA
|
||
02111-1307, USA. */
|
||
|
||
#include "config.h"
|
||
#include "system.h"
|
||
#include "coretypes.h"
|
||
#include "tm.h"
|
||
#include "tree.h"
|
||
#include "flags.h"
|
||
#include "toplev.h"
|
||
#include "output.h"
|
||
#include "rtl.h"
|
||
#include "ggc.h"
|
||
#include "expr.h"
|
||
#include "tm_p.h"
|
||
#include "cpplib.h"
|
||
#include "target.h"
|
||
#include "langhooks.h"
|
||
|
||
static void init_attributes (void);
|
||
|
||
/* Table of the tables of attributes (common, language, format, machine)
|
||
searched. */
|
||
static const struct attribute_spec *attribute_tables[4];
|
||
|
||
static bool attributes_initialized = false;
|
||
|
||
/* Default empty table of attributes. */
|
||
static const struct attribute_spec empty_attribute_table[] =
|
||
{
|
||
{ NULL, 0, 0, false, false, false, NULL }
|
||
};
|
||
|
||
/* Initialize attribute tables, and make some sanity checks
|
||
if --enable-checking. */
|
||
|
||
static void
|
||
init_attributes (void)
|
||
{
|
||
size_t i;
|
||
|
||
attribute_tables[0] = lang_hooks.common_attribute_table;
|
||
attribute_tables[1] = lang_hooks.attribute_table;
|
||
attribute_tables[2] = lang_hooks.format_attribute_table;
|
||
attribute_tables[3] = targetm.attribute_table;
|
||
|
||
/* Translate NULL pointers to pointers to the empty table. */
|
||
for (i = 0; i < ARRAY_SIZE (attribute_tables); i++)
|
||
if (attribute_tables[i] == NULL)
|
||
attribute_tables[i] = empty_attribute_table;
|
||
|
||
#ifdef ENABLE_CHECKING
|
||
/* Make some sanity checks on the attribute tables. */
|
||
for (i = 0; i < ARRAY_SIZE (attribute_tables); i++)
|
||
{
|
||
int j;
|
||
|
||
for (j = 0; attribute_tables[i][j].name != NULL; j++)
|
||
{
|
||
/* The name must not begin and end with __. */
|
||
const char *name = attribute_tables[i][j].name;
|
||
int len = strlen (name);
|
||
if (name[0] == '_' && name[1] == '_'
|
||
&& name[len - 1] == '_' && name[len - 2] == '_')
|
||
abort ();
|
||
/* The minimum and maximum lengths must be consistent. */
|
||
if (attribute_tables[i][j].min_length < 0)
|
||
abort ();
|
||
if (attribute_tables[i][j].max_length != -1
|
||
&& (attribute_tables[i][j].max_length
|
||
< attribute_tables[i][j].min_length))
|
||
abort ();
|
||
/* An attribute cannot require both a DECL and a TYPE. */
|
||
if (attribute_tables[i][j].decl_required
|
||
&& attribute_tables[i][j].type_required)
|
||
abort ();
|
||
/* If an attribute requires a function type, in particular
|
||
it requires a type. */
|
||
if (attribute_tables[i][j].function_type_required
|
||
&& !attribute_tables[i][j].type_required)
|
||
abort ();
|
||
}
|
||
}
|
||
|
||
/* Check that each name occurs just once in each table. */
|
||
for (i = 0; i < ARRAY_SIZE (attribute_tables); i++)
|
||
{
|
||
int j, k;
|
||
for (j = 0; attribute_tables[i][j].name != NULL; j++)
|
||
for (k = j + 1; attribute_tables[i][k].name != NULL; k++)
|
||
if (!strcmp (attribute_tables[i][j].name,
|
||
attribute_tables[i][k].name))
|
||
abort ();
|
||
}
|
||
/* Check that no name occurs in more than one table. */
|
||
for (i = 0; i < ARRAY_SIZE (attribute_tables); i++)
|
||
{
|
||
size_t j, k, l;
|
||
|
||
for (j = i + 1; j < ARRAY_SIZE (attribute_tables); j++)
|
||
for (k = 0; attribute_tables[i][k].name != NULL; k++)
|
||
for (l = 0; attribute_tables[j][l].name != NULL; l++)
|
||
if (!strcmp (attribute_tables[i][k].name,
|
||
attribute_tables[j][l].name))
|
||
abort ();
|
||
}
|
||
#endif
|
||
|
||
attributes_initialized = true;
|
||
}
|
||
|
||
/* Process the attributes listed in ATTRIBUTES and install them in *NODE,
|
||
which is either a DECL (including a TYPE_DECL) or a TYPE. If a DECL,
|
||
it should be modified in place; if a TYPE, a copy should be created
|
||
unless ATTR_FLAG_TYPE_IN_PLACE is set in FLAGS. FLAGS gives further
|
||
information, in the form of a bitwise OR of flags in enum attribute_flags
|
||
from tree.h. Depending on these flags, some attributes may be
|
||
returned to be applied at a later stage (for example, to apply
|
||
a decl attribute to the declaration rather than to its type). */
|
||
|
||
tree
|
||
decl_attributes (tree *node, tree attributes, int flags)
|
||
{
|
||
tree a;
|
||
tree returned_attrs = NULL_TREE;
|
||
|
||
if (!attributes_initialized)
|
||
init_attributes ();
|
||
|
||
(*targetm.insert_attributes) (*node, &attributes);
|
||
|
||
for (a = attributes; a; a = TREE_CHAIN (a))
|
||
{
|
||
tree name = TREE_PURPOSE (a);
|
||
tree args = TREE_VALUE (a);
|
||
tree *anode = node;
|
||
const struct attribute_spec *spec = NULL;
|
||
bool no_add_attrs = 0;
|
||
tree fn_ptr_tmp = NULL_TREE;
|
||
size_t i;
|
||
|
||
for (i = 0; i < ARRAY_SIZE (attribute_tables); i++)
|
||
{
|
||
int j;
|
||
|
||
for (j = 0; attribute_tables[i][j].name != NULL; j++)
|
||
{
|
||
if (is_attribute_p (attribute_tables[i][j].name, name))
|
||
{
|
||
spec = &attribute_tables[i][j];
|
||
break;
|
||
}
|
||
}
|
||
if (spec != NULL)
|
||
break;
|
||
}
|
||
|
||
if (spec == NULL)
|
||
{
|
||
warning ("`%s' attribute directive ignored",
|
||
IDENTIFIER_POINTER (name));
|
||
continue;
|
||
}
|
||
else if (list_length (args) < spec->min_length
|
||
|| (spec->max_length >= 0
|
||
&& list_length (args) > spec->max_length))
|
||
{
|
||
error ("wrong number of arguments specified for `%s' attribute",
|
||
IDENTIFIER_POINTER (name));
|
||
continue;
|
||
}
|
||
|
||
if (spec->decl_required && !DECL_P (*anode))
|
||
{
|
||
if (flags & ((int) ATTR_FLAG_DECL_NEXT
|
||
| (int) ATTR_FLAG_FUNCTION_NEXT
|
||
| (int) ATTR_FLAG_ARRAY_NEXT))
|
||
{
|
||
/* Pass on this attribute to be tried again. */
|
||
returned_attrs = tree_cons (name, args, returned_attrs);
|
||
continue;
|
||
}
|
||
else
|
||
{
|
||
warning ("`%s' attribute does not apply to types",
|
||
IDENTIFIER_POINTER (name));
|
||
continue;
|
||
}
|
||
}
|
||
|
||
/* If we require a type, but were passed a decl, set up to make a
|
||
new type and update the one in the decl. ATTR_FLAG_TYPE_IN_PLACE
|
||
would have applied if we'd been passed a type, but we cannot modify
|
||
the decl's type in place here. */
|
||
if (spec->type_required && DECL_P (*anode))
|
||
{
|
||
anode = &TREE_TYPE (*anode);
|
||
flags &= ~(int) ATTR_FLAG_TYPE_IN_PLACE;
|
||
}
|
||
|
||
if (spec->function_type_required && TREE_CODE (*anode) != FUNCTION_TYPE
|
||
&& TREE_CODE (*anode) != METHOD_TYPE)
|
||
{
|
||
if (TREE_CODE (*anode) == POINTER_TYPE
|
||
&& (TREE_CODE (TREE_TYPE (*anode)) == FUNCTION_TYPE
|
||
|| TREE_CODE (TREE_TYPE (*anode)) == METHOD_TYPE))
|
||
{
|
||
/* OK, this is a bit convoluted. We can't just make a copy
|
||
of the pointer type and modify its TREE_TYPE, because if
|
||
we change the attributes of the target type the pointer
|
||
type needs to have a different TYPE_MAIN_VARIANT. So we
|
||
pull out the target type now, frob it as appropriate, and
|
||
rebuild the pointer type later.
|
||
|
||
This would all be simpler if attributes were part of the
|
||
declarator, grumble grumble. */
|
||
fn_ptr_tmp = TREE_TYPE (*anode);
|
||
anode = &fn_ptr_tmp;
|
||
flags &= ~(int) ATTR_FLAG_TYPE_IN_PLACE;
|
||
}
|
||
else if (flags & (int) ATTR_FLAG_FUNCTION_NEXT)
|
||
{
|
||
/* Pass on this attribute to be tried again. */
|
||
returned_attrs = tree_cons (name, args, returned_attrs);
|
||
continue;
|
||
}
|
||
|
||
if (TREE_CODE (*anode) != FUNCTION_TYPE
|
||
&& TREE_CODE (*anode) != METHOD_TYPE)
|
||
{
|
||
warning ("`%s' attribute only applies to function types",
|
||
IDENTIFIER_POINTER (name));
|
||
continue;
|
||
}
|
||
}
|
||
|
||
if (spec->handler != NULL)
|
||
returned_attrs = chainon ((*spec->handler) (anode, name, args,
|
||
flags, &no_add_attrs),
|
||
returned_attrs);
|
||
|
||
/* Layout the decl in case anything changed. */
|
||
if (spec->type_required && DECL_P (*node)
|
||
&& (TREE_CODE (*node) == VAR_DECL
|
||
|| TREE_CODE (*node) == PARM_DECL
|
||
|| TREE_CODE (*node) == RESULT_DECL))
|
||
{
|
||
/* Force a recalculation of mode and size. */
|
||
DECL_MODE (*node) = VOIDmode;
|
||
DECL_SIZE (*node) = 0;
|
||
|
||
layout_decl (*node, 0);
|
||
}
|
||
|
||
if (!no_add_attrs)
|
||
{
|
||
tree old_attrs;
|
||
tree a;
|
||
|
||
if (DECL_P (*anode))
|
||
old_attrs = DECL_ATTRIBUTES (*anode);
|
||
else
|
||
old_attrs = TYPE_ATTRIBUTES (*anode);
|
||
|
||
for (a = lookup_attribute (spec->name, old_attrs);
|
||
a != NULL_TREE;
|
||
a = lookup_attribute (spec->name, TREE_CHAIN (a)))
|
||
{
|
||
if (simple_cst_equal (TREE_VALUE (a), args) == 1)
|
||
break;
|
||
}
|
||
|
||
if (a == NULL_TREE)
|
||
{
|
||
/* This attribute isn't already in the list. */
|
||
if (DECL_P (*anode))
|
||
DECL_ATTRIBUTES (*anode) = tree_cons (name, args, old_attrs);
|
||
else if (flags & (int) ATTR_FLAG_TYPE_IN_PLACE)
|
||
TYPE_ATTRIBUTES (*anode) = tree_cons (name, args, old_attrs);
|
||
else
|
||
*anode = build_type_attribute_variant (*anode,
|
||
tree_cons (name, args,
|
||
old_attrs));
|
||
}
|
||
}
|
||
|
||
if (fn_ptr_tmp)
|
||
{
|
||
/* Rebuild the function pointer type and put it in the
|
||
appropriate place. */
|
||
fn_ptr_tmp = build_pointer_type (fn_ptr_tmp);
|
||
if (DECL_P (*node))
|
||
TREE_TYPE (*node) = fn_ptr_tmp;
|
||
else if (TREE_CODE (*node) == POINTER_TYPE)
|
||
*node = fn_ptr_tmp;
|
||
else
|
||
abort ();
|
||
}
|
||
}
|
||
|
||
return returned_attrs;
|
||
}
|
||
|
||
/* Split SPECS_ATTRS, a list of declspecs and prefix attributes, into two
|
||
lists. SPECS_ATTRS may also be just a typespec (eg: RECORD_TYPE).
|
||
|
||
The head of the declspec list is stored in DECLSPECS.
|
||
The head of the attribute list is stored in PREFIX_ATTRIBUTES.
|
||
|
||
Note that attributes in SPECS_ATTRS are stored in the TREE_PURPOSE of
|
||
the list elements. We drop the containing TREE_LIST nodes and link the
|
||
resulting attributes together the way decl_attributes expects them. */
|
||
|
||
void
|
||
split_specs_attrs (tree specs_attrs, tree *declspecs, tree *prefix_attributes)
|
||
{
|
||
tree t, s, a, next, specs, attrs;
|
||
|
||
/* This can happen after an __extension__ in pedantic mode. */
|
||
if (specs_attrs != NULL_TREE
|
||
&& TREE_CODE (specs_attrs) == INTEGER_CST)
|
||
{
|
||
*declspecs = NULL_TREE;
|
||
*prefix_attributes = NULL_TREE;
|
||
return;
|
||
}
|
||
|
||
/* This can happen in c++ (eg: decl: typespec initdecls ';'). */
|
||
if (specs_attrs != NULL_TREE
|
||
&& TREE_CODE (specs_attrs) != TREE_LIST)
|
||
{
|
||
*declspecs = specs_attrs;
|
||
*prefix_attributes = NULL_TREE;
|
||
return;
|
||
}
|
||
|
||
/* Remember to keep the lists in the same order, element-wise. */
|
||
|
||
specs = s = NULL_TREE;
|
||
attrs = a = NULL_TREE;
|
||
for (t = specs_attrs; t; t = next)
|
||
{
|
||
next = TREE_CHAIN (t);
|
||
/* Declspecs have a non-NULL TREE_VALUE. */
|
||
if (TREE_VALUE (t) != NULL_TREE)
|
||
{
|
||
if (specs == NULL_TREE)
|
||
specs = s = t;
|
||
else
|
||
{
|
||
TREE_CHAIN (s) = t;
|
||
s = t;
|
||
}
|
||
}
|
||
/* The TREE_PURPOSE may also be empty in the case of
|
||
__attribute__(()). */
|
||
else if (TREE_PURPOSE (t) != NULL_TREE)
|
||
{
|
||
if (attrs == NULL_TREE)
|
||
attrs = a = TREE_PURPOSE (t);
|
||
else
|
||
{
|
||
TREE_CHAIN (a) = TREE_PURPOSE (t);
|
||
a = TREE_PURPOSE (t);
|
||
}
|
||
/* More attrs can be linked here, move A to the end. */
|
||
while (TREE_CHAIN (a) != NULL_TREE)
|
||
a = TREE_CHAIN (a);
|
||
}
|
||
}
|
||
|
||
/* Terminate the lists. */
|
||
if (s != NULL_TREE)
|
||
TREE_CHAIN (s) = NULL_TREE;
|
||
if (a != NULL_TREE)
|
||
TREE_CHAIN (a) = NULL_TREE;
|
||
|
||
/* All done. */
|
||
*declspecs = specs;
|
||
*prefix_attributes = attrs;
|
||
}
|
||
|
||
/* Strip attributes from SPECS_ATTRS, a list of declspecs and attributes.
|
||
This function is used by the parser when a rule will accept attributes
|
||
in a particular position, but we don't want to support that just yet.
|
||
|
||
A warning is issued for every ignored attribute. */
|
||
|
||
tree
|
||
strip_attrs (tree specs_attrs)
|
||
{
|
||
tree specs, attrs;
|
||
|
||
split_specs_attrs (specs_attrs, &specs, &attrs);
|
||
|
||
while (attrs)
|
||
{
|
||
warning ("`%s' attribute ignored",
|
||
IDENTIFIER_POINTER (TREE_PURPOSE (attrs)));
|
||
attrs = TREE_CHAIN (attrs);
|
||
}
|
||
|
||
return specs;
|
||
}
|