/* Generic routines for manipulating SSA_NAME expressions
- Copyright (C) 2003, 2004, 2005, 2007, 2008, 2009
+ Copyright (C) 2003, 2004, 2005, 2007, 2008, 2009, 2010
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 3, 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 COPYING3. If not see
<http://www.gnu.org/licenses/>. */
#include "coretypes.h"
#include "tm.h"
#include "tree.h"
-#include "varray.h"
-#include "ggc.h"
#include "tree-flow.h"
#include "tree-pass.h"
/* Rewriting a function into SSA form can create a huge number of SSA_NAMEs,
many of which may be thrown away shortly after their creation if jumps
- were threaded through PHI nodes.
+ were threaded through PHI nodes.
While our garbage collection mechanisms will handle this situation, it
is extremely wasteful to create nodes and throw them away, especially
Right now we maintain our free list on a per-function basis. It may
or may not make sense to maintain the free list for the duration of
- a compilation unit.
+ a compilation unit.
External code should rely solely upon HIGHEST_SSA_VERSION and the
externally defined functions. External code should not know about
/* We no longer need the SSA_NAME expression VAR, release it so that
- it may be reused.
+ it may be reused.
Note it is assumed that no calls to make_ssa_name will be made
until all uses of the ssa name are released and that the only
/* release_ssa_name can be called multiple times on a single SSA_NAME.
However, it should only end up on our free list one time. We
keep a status bit in the SSA_NAME node itself to indicate it has
- been put on the free list.
+ been put on the free list.
Note that once on the freelist you can not reference the SSA_NAME's
defining statement. */
}
}
-/* Creates a duplicate of a ssa name NAME defined in statement STMT. */
-tree
-duplicate_ssa_name (tree name, gimple stmt)
+/* Return the alias information associated with pointer T. It creates a
+ new instance if none existed. */
+
+struct ptr_info_def *
+get_ptr_info (tree t)
{
- tree new_name = make_ssa_name (SSA_NAME_VAR (name), stmt);
- struct ptr_info_def *old_ptr_info = SSA_NAME_PTR_INFO (name);
+ struct ptr_info_def *pi;
- if (old_ptr_info)
- duplicate_ssa_name_ptr_info (new_name, old_ptr_info);
+ gcc_assert (POINTER_TYPE_P (TREE_TYPE (t)));
- return new_name;
-}
+ pi = SSA_NAME_PTR_INFO (t);
+ if (pi == NULL)
+ {
+ pi = ggc_alloc_cleared_ptr_info_def ();
+ pt_solution_reset (&pi->pt);
+ pi->align = 1;
+ pi->misalign = 0;
+ SSA_NAME_PTR_INFO (t) = pi;
+ }
+ return pi;
+}
/* Creates a duplicate of the ptr_info_def at PTR_INFO for use by
the SSA name NAME. */
if (!ptr_info)
return;
- new_ptr_info = GGC_NEW (struct ptr_info_def);
+ new_ptr_info = ggc_alloc_ptr_info_def ();
*new_ptr_info = *ptr_info;
SSA_NAME_PTR_INFO (name) = new_ptr_info;
}
+/* Creates a duplicate of a ssa name NAME tobe defined by statement STMT. */
+
+tree
+duplicate_ssa_name (tree name, gimple stmt)
+{
+ tree new_name = make_ssa_name (SSA_NAME_VAR (name), stmt);
+ struct ptr_info_def *old_ptr_info = SSA_NAME_PTR_INFO (name);
+
+ if (old_ptr_info)
+ duplicate_ssa_name_ptr_info (new_name, old_ptr_info);
+
+ return new_name;
+}
+
+
/* Release all the SSA_NAMEs created by STMT. */
void
int n = 0;
referenced_var_iterator rvi;
- /* Current defs point to various dead SSA names that in turn points to dead
- statements so bunch of dead memory is held from releasing. */
- FOR_EACH_REFERENCED_VAR (t, rvi)
+ /* Current defs point to various dead SSA names that in turn point to
+ eventually dead variables so a bunch of memory is held live. */
+ FOR_EACH_REFERENCED_VAR (cfun, t, rvi)
set_current_def (t, NULL);
/* Now release the freelist. */
for (t = FREE_SSANAMES (cfun); t; t = next)
}
FREE_SSANAMES (cfun) = NULL;
- /* Cgraph edges has been invalidated and point to dead statement. We need to
- remove them now and will rebuild it before next IPA pass. */
- cgraph_node_remove_callees (cgraph_node (current_function_decl));
-
+ statistics_counter_event (cfun, "SSA names released", n);
if (dump_file)
- fprintf (dump_file, "Released %i names, %.2f%%\n", n, n * 100.0 / num_ssa_names);
+ fprintf (dump_file, "Released %i names, %.2f%%\n",
+ n, n * 100.0 / num_ssa_names);
return 0;
}
NULL, /* sub */
NULL, /* next */
0, /* static_pass_number */
- TV_NONE, /* tv_id */
+ TV_TREE_SSA_OTHER, /* tv_id */
PROP_ssa, /* properties_required */
0, /* properties_provided */
0, /* properties_destroyed */
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