freebsd-dev/contrib/gcc/cp/optimize.c
2007-05-19 01:19:51 +00:00

219 lines
6.9 KiB
C

/* Perform optimizations on tree structure.
Copyright (C) 1998, 1999, 2000, 2001, 2002, 2004, 2005
Free Software Foundation, Inc.
Written by Mark Michell (mark@codesourcery.com).
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, 51 Franklin Street, Fifth Floor, Boston, MA
02110-1301, USA. */
#include "config.h"
#include "system.h"
#include "coretypes.h"
#include "tm.h"
#include "tree.h"
#include "cp-tree.h"
#include "rtl.h"
#include "insn-config.h"
#include "input.h"
#include "integrate.h"
#include "toplev.h"
#include "varray.h"
#include "params.h"
#include "hashtab.h"
#include "target.h"
#include "debug.h"
#include "tree-inline.h"
#include "flags.h"
#include "langhooks.h"
#include "diagnostic.h"
#include "tree-dump.h"
#include "tree-gimple.h"
/* Prototypes. */
static void update_cloned_parm (tree, tree, bool);
/* CLONED_PARM is a copy of CLONE, generated for a cloned constructor
or destructor. Update it to ensure that the source-position for
the cloned parameter matches that for the original, and that the
debugging generation code will be able to find the original PARM. */
static void
update_cloned_parm (tree parm, tree cloned_parm, bool first)
{
DECL_ABSTRACT_ORIGIN (cloned_parm) = parm;
/* We may have taken its address. */
TREE_ADDRESSABLE (cloned_parm) = TREE_ADDRESSABLE (parm);
/* The definition might have different constness. */
TREE_READONLY (cloned_parm) = TREE_READONLY (parm);
TREE_USED (cloned_parm) = !first || TREE_USED (parm);
/* The name may have changed from the declaration. */
DECL_NAME (cloned_parm) = DECL_NAME (parm);
DECL_SOURCE_LOCATION (cloned_parm) = DECL_SOURCE_LOCATION (parm);
TREE_TYPE (cloned_parm) = TREE_TYPE (parm);
DECL_COMPLEX_GIMPLE_REG_P (cloned_parm) = DECL_COMPLEX_GIMPLE_REG_P (parm);
}
/* FN is a function that has a complete body. Clone the body as
necessary. Returns nonzero if there's no longer any need to
process the main body. */
bool
maybe_clone_body (tree fn)
{
tree clone;
bool first = true;
/* We only clone constructors and destructors. */
if (!DECL_MAYBE_IN_CHARGE_CONSTRUCTOR_P (fn)
&& !DECL_MAYBE_IN_CHARGE_DESTRUCTOR_P (fn))
return 0;
/* Emit the DWARF1 abstract instance. */
(*debug_hooks->deferred_inline_function) (fn);
/* We know that any clones immediately follow FN in the TYPE_METHODS
list. */
push_to_top_level ();
FOR_EACH_CLONE (clone, fn)
{
tree parm;
tree clone_parm;
int parmno;
splay_tree decl_map;
/* Update CLONE's source position information to match FN's. */
DECL_SOURCE_LOCATION (clone) = DECL_SOURCE_LOCATION (fn);
DECL_INLINE (clone) = DECL_INLINE (fn);
DECL_DECLARED_INLINE_P (clone) = DECL_DECLARED_INLINE_P (fn);
DECL_COMDAT (clone) = DECL_COMDAT (fn);
DECL_WEAK (clone) = DECL_WEAK (fn);
DECL_ONE_ONLY (clone) = DECL_ONE_ONLY (fn);
DECL_SECTION_NAME (clone) = DECL_SECTION_NAME (fn);
DECL_USE_TEMPLATE (clone) = DECL_USE_TEMPLATE (fn);
DECL_EXTERNAL (clone) = DECL_EXTERNAL (fn);
DECL_INTERFACE_KNOWN (clone) = DECL_INTERFACE_KNOWN (fn);
DECL_NOT_REALLY_EXTERN (clone) = DECL_NOT_REALLY_EXTERN (fn);
TREE_PUBLIC (clone) = TREE_PUBLIC (fn);
DECL_VISIBILITY (clone) = DECL_VISIBILITY (fn);
DECL_VISIBILITY_SPECIFIED (clone) = DECL_VISIBILITY_SPECIFIED (fn);
/* Adjust the parameter names and locations. */
parm = DECL_ARGUMENTS (fn);
clone_parm = DECL_ARGUMENTS (clone);
/* Update the `this' parameter, which is always first. */
update_cloned_parm (parm, clone_parm, first);
parm = TREE_CHAIN (parm);
clone_parm = TREE_CHAIN (clone_parm);
if (DECL_HAS_IN_CHARGE_PARM_P (fn))
parm = TREE_CHAIN (parm);
if (DECL_HAS_VTT_PARM_P (fn))
parm = TREE_CHAIN (parm);
if (DECL_HAS_VTT_PARM_P (clone))
clone_parm = TREE_CHAIN (clone_parm);
for (; parm;
parm = TREE_CHAIN (parm), clone_parm = TREE_CHAIN (clone_parm))
/* Update this parameter. */
update_cloned_parm (parm, clone_parm, first);
/* Start processing the function. */
start_preparsed_function (clone, NULL_TREE, SF_PRE_PARSED);
/* Remap the parameters. */
decl_map = splay_tree_new (splay_tree_compare_pointers, NULL, NULL);
for (parmno = 0,
parm = DECL_ARGUMENTS (fn),
clone_parm = DECL_ARGUMENTS (clone);
parm;
++parmno,
parm = TREE_CHAIN (parm))
{
/* Map the in-charge parameter to an appropriate constant. */
if (DECL_HAS_IN_CHARGE_PARM_P (fn) && parmno == 1)
{
tree in_charge;
in_charge = in_charge_arg_for_name (DECL_NAME (clone));
splay_tree_insert (decl_map,
(splay_tree_key) parm,
(splay_tree_value) in_charge);
}
else if (DECL_ARTIFICIAL (parm)
&& DECL_NAME (parm) == vtt_parm_identifier)
{
/* For a subobject constructor or destructor, the next
argument is the VTT parameter. Remap the VTT_PARM
from the CLONE to this parameter. */
if (DECL_HAS_VTT_PARM_P (clone))
{
DECL_ABSTRACT_ORIGIN (clone_parm) = parm;
splay_tree_insert (decl_map,
(splay_tree_key) parm,
(splay_tree_value) clone_parm);
clone_parm = TREE_CHAIN (clone_parm);
}
/* Otherwise, map the VTT parameter to `NULL'. */
else
{
splay_tree_insert (decl_map,
(splay_tree_key) parm,
(splay_tree_value) null_pointer_node);
}
}
/* Map other parameters to their equivalents in the cloned
function. */
else
{
splay_tree_insert (decl_map,
(splay_tree_key) parm,
(splay_tree_value) clone_parm);
clone_parm = TREE_CHAIN (clone_parm);
}
}
if (targetm.cxx.cdtor_returns_this ())
{
parm = DECL_RESULT (fn);
clone_parm = DECL_RESULT (clone);
splay_tree_insert (decl_map, (splay_tree_key) parm,
(splay_tree_value) clone_parm);
}
/* Clone the body. */
clone_body (clone, fn, decl_map);
/* Clean up. */
splay_tree_delete (decl_map);
/* The clone can throw iff the original function can throw. */
cp_function_chain->can_throw = !TREE_NOTHROW (fn);
/* Now, expand this function into RTL, if appropriate. */
finish_function (0);
BLOCK_ABSTRACT_ORIGIN (DECL_INITIAL (clone)) = DECL_INITIAL (fn);
expand_or_defer_fn (clone);
first = false;
}
pop_from_top_level ();
/* We don't need to process the original function any further. */
return 1;
}