/* Data flow functions for trees.
- Copyright (C) 2001, 2002, 2003, 2004, 2005 Free Software Foundation, Inc.
+ Copyright (C) 2001, 2002, 2003, 2004, 2005, 2007, 2008, 2009
+ Free Software Foundation, Inc.
Contributed by Diego Novillo <dnovillo@redhat.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)
+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,
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. */
+along with GCC; see the file COPYING3. If not see
+<http://www.gnu.org/licenses/>. */
#include "config.h"
#include "system.h"
#include "function.h"
#include "diagnostic.h"
#include "tree-dump.h"
-#include "tree-gimple.h"
+#include "gimple.h"
#include "tree-flow.h"
#include "tree-inline.h"
#include "tree-pass.h"
/* Counters used to display DFA and SSA statistics. */
struct dfa_stats_d
{
- long num_stmt_anns;
long num_var_anns;
long num_defs;
long num_uses;
long num_phis;
long num_phi_args;
- int max_num_phi_args;
- long num_v_may_defs;
+ size_t max_num_phi_args;
+ long num_vdefs;
long num_vuses;
- long num_v_must_defs;
-};
-
-
-/* State information for find_vars_r. */
-struct walk_state
-{
- /* Hash table used to avoid adding the same variable more than once. */
- htab_t vars_found;
};
/* Local functions. */
static void collect_dfa_stats (struct dfa_stats_d *);
-static tree collect_dfa_stats_r (tree *, int *, void *);
static tree find_vars_r (tree *, int *, void *);
-static void add_referenced_var (tree, struct walk_state *);
-
-
-/* Global declarations. */
-
-/* Array of all variables referenced in the function. */
-htab_t referenced_vars;
/*---------------------------------------------------------------------------
various attributes for each variable used by alias analysis and the
optimizer. */
-static void
+static unsigned int
find_referenced_vars (void)
{
- htab_t vars_found;
basic_block bb;
- block_stmt_iterator si;
- struct walk_state walk_state;
-
- vars_found = htab_create (50, htab_hash_pointer, htab_eq_pointer, NULL);
- memset (&walk_state, 0, sizeof (walk_state));
- walk_state.vars_found = vars_found;
+ gimple_stmt_iterator si;
FOR_EACH_BB (bb)
- for (si = bsi_start (bb); !bsi_end_p (si); bsi_next (&si))
- {
- tree *stmt_p = bsi_stmt_ptr (si);
- walk_tree (stmt_p, find_vars_r, &walk_state, NULL);
- }
+ {
+ for (si = gsi_start_bb (bb); !gsi_end_p (si); gsi_next (&si))
+ find_referenced_vars_in (gsi_stmt (si));
+
+ for (si = gsi_start_phis (bb); !gsi_end_p (si); gsi_next (&si))
+ find_referenced_vars_in (gsi_stmt (si));
+ }
- htab_delete (vars_found);
+ return 0;
}
-struct tree_opt_pass pass_referenced_vars =
+struct gimple_opt_pass pass_referenced_vars =
{
+ {
+ GIMPLE_PASS,
NULL, /* name */
NULL, /* gate */
find_referenced_vars, /* execute */
PROP_gimple_leh | PROP_cfg, /* properties_required */
PROP_referenced_vars, /* properties_provided */
0, /* properties_destroyed */
- 0, /* todo_flags_start */
- 0, /* todo_flags_finish */
- 0 /* letter */
+ TODO_dump_func, /* todo_flags_start */
+ TODO_dump_func /* todo_flags_finish */
+ }
};
gcc_assert (t);
gcc_assert (DECL_P (t));
- gcc_assert (!t->common.ann || t->common.ann->common.type == VAR_ANN);
-
- ann = ggc_alloc (sizeof (*ann));
- memset ((void *) ann, 0, sizeof (*ann));
+ gcc_assert (!t->base.ann || t->base.ann->common.type == VAR_ANN);
+ ann = GGC_CNEW (struct var_ann_d);
ann->common.type = VAR_ANN;
-
- t->common.ann = (tree_ann_t) ann;
+ t->base.ann = (tree_ann_t) ann;
return ann;
}
+/* Renumber all of the gimple stmt uids. */
-/* Create a new annotation for a statement node T. */
-
-stmt_ann_t
-create_stmt_ann (tree t)
+void
+renumber_gimple_stmt_uids (void)
{
- stmt_ann_t ann;
-
- gcc_assert (is_gimple_stmt (t));
- gcc_assert (!t->common.ann || t->common.ann->common.type == STMT_ANN);
-
- ann = ggc_alloc (sizeof (*ann));
- memset ((void *) ann, 0, sizeof (*ann));
-
- ann->common.type = STMT_ANN;
-
- /* Since we just created the annotation, mark the statement modified. */
- ann->modified = true;
-
- t->common.ann = (tree_ann_t) ann;
+ basic_block bb;
- return ann;
+ set_gimple_stmt_max_uid (cfun, 0);
+ FOR_ALL_BB (bb)
+ {
+ gimple_stmt_iterator bsi;
+ for (bsi = gsi_start_bb (bb); !gsi_end_p (bsi); gsi_next (&bsi))
+ {
+ gimple stmt = gsi_stmt (bsi);
+ gimple_set_uid (stmt, inc_gimple_stmt_max_uid (cfun));
+ }
+ }
}
/* Create a new annotation for a tree T. */
-tree_ann_t
-create_tree_ann (tree t)
+tree_ann_common_t
+create_tree_common_ann (tree t)
{
- tree_ann_t ann;
+ tree_ann_common_t ann;
gcc_assert (t);
- gcc_assert (!t->common.ann || t->common.ann->common.type == TREE_ANN_COMMON);
+ gcc_assert (!t->base.ann || t->base.ann->common.type == TREE_ANN_COMMON);
- ann = ggc_alloc (sizeof (*ann));
- memset ((void *) ann, 0, sizeof (*ann));
+ ann = GGC_CNEW (struct tree_ann_common_d);
- ann->common.type = TREE_ANN_COMMON;
- t->common.ann = ann;
+ ann->type = TREE_ANN_COMMON;
+ ann->rn = -1;
+ t->base.ann = (tree_ann_t) ann;
return ann;
}
make_rename_temp (tree type, const char *prefix)
{
tree t = create_tmp_var (type, prefix);
- if (referenced_vars)
+
+ if (TREE_CODE (TREE_TYPE (t)) == COMPLEX_TYPE
+ || TREE_CODE (TREE_TYPE (t)) == VECTOR_TYPE)
+ DECL_GIMPLE_REG_P (t) = 1;
+
+ if (gimple_referenced_vars (cfun))
{
- add_referenced_tmp_var (t);
+ add_referenced_var (t);
mark_sym_for_renaming (t);
}
{
fprintf (file, "Variable: ");
dump_variable (file, var);
- fprintf (file, "\n");
}
+
+ fprintf (file, "\n");
}
}
-/* Dump sub-variables for VAR to FILE. */
-
-void
-dump_subvars_for (FILE *file, tree var)
-{
- subvar_t sv = get_subvars_for_var (var);
-
- if (!sv)
- return;
-
- fprintf (file, "{ ");
-
- for (; sv; sv = sv->next)
- {
- print_generic_expr (file, sv->var, dump_flags);
- fprintf (file, " ");
- }
-
- fprintf (file, "}");
-}
-
-
-/* Dumb sub-variables for VAR to stderr. */
-
-void
-debug_subvars_for (tree var)
-{
- dump_subvars_for (stderr, var);
-}
-
-
/* Dump variable VAR and its may-aliases to FILE. */
void
ann = var_ann (var);
- fprintf (file, ", UID %u", (unsigned) DECL_UID (var));
+ fprintf (file, ", UID D.%u", (unsigned) DECL_UID (var));
fprintf (file, ", ");
print_generic_expr (file, TREE_TYPE (var), dump_flags);
- if (ann && ann->type_mem_tag)
- {
- fprintf (file, ", type memory tag: ");
- print_generic_expr (file, ann->type_mem_tag, dump_flags);
- }
-
- if (ann && ann->is_alias_tag)
- fprintf (file, ", is an alias tag");
-
if (TREE_ADDRESSABLE (var))
fprintf (file, ", is addressable");
if (is_call_clobbered (var))
fprintf (file, ", call clobbered");
-
- if (default_def (var))
+ else if (is_call_used (var))
+ fprintf (file, ", call used");
+
+ if (ann && ann->noalias_state == NO_ALIAS)
+ fprintf (file, ", NO_ALIAS (does not alias other NO_ALIAS symbols)");
+ else if (ann && ann->noalias_state == NO_ALIAS_GLOBAL)
+ fprintf (file, ", NO_ALIAS_GLOBAL (does not alias other NO_ALIAS symbols"
+ " and global vars)");
+ else if (ann && ann->noalias_state == NO_ALIAS_ANYTHING)
+ fprintf (file, ", NO_ALIAS_ANYTHING (does not alias any other symbols)");
+
+ if (cfun && gimple_default_def (cfun, var))
{
fprintf (file, ", default def: ");
- print_generic_expr (file, default_def (var), dump_flags);
- }
-
- if (may_aliases (var))
- {
- fprintf (file, ", may aliases: ");
- dump_may_aliases_for (file, var);
+ print_generic_expr (file, gimple_default_def (cfun, var), dump_flags);
}
- if (get_subvars_for_var (var))
+ if (DECL_INITIAL (var))
{
- fprintf (file, ", sub-vars: ");
- dump_subvars_for (file, var);
+ fprintf (file, ", initial: ");
+ print_generic_expr (file, DECL_INITIAL (var), dump_flags);
}
fprintf (file, "\n");
fprintf (file, fmt_str_1, "Referenced variables", (unsigned long)num_referenced_vars,
SCALE (size), LABEL (size));
- size = dfa_stats.num_stmt_anns * sizeof (struct stmt_ann_d);
- total += size;
- fprintf (file, fmt_str_1, "Statements annotated", dfa_stats.num_stmt_anns,
- SCALE (size), LABEL (size));
-
size = dfa_stats.num_var_anns * sizeof (struct var_ann_d);
total += size;
fprintf (file, fmt_str_1, "Variables annotated", dfa_stats.num_var_anns,
fprintf (file, fmt_str_1, "VUSE operands", dfa_stats.num_vuses,
SCALE (size), LABEL (size));
- size = dfa_stats.num_v_may_defs * sizeof (tree *);
- total += size;
- fprintf (file, fmt_str_1, "V_MAY_DEF operands", dfa_stats.num_v_may_defs,
- SCALE (size), LABEL (size));
-
- size = dfa_stats.num_v_must_defs * sizeof (tree *);
+ size = dfa_stats.num_vdefs * sizeof (tree *);
total += size;
- fprintf (file, fmt_str_1, "V_MUST_DEF operands", dfa_stats.num_v_must_defs,
+ fprintf (file, fmt_str_1, "VDEF operands", dfa_stats.num_vdefs,
SCALE (size), LABEL (size));
- size = dfa_stats.num_phis * sizeof (struct tree_phi_node);
+ size = dfa_stats.num_phis * sizeof (struct gimple_statement_phi);
total += size;
fprintf (file, fmt_str_1, "PHI nodes", dfa_stats.num_phis,
SCALE (size), LABEL (size));
fprintf (file, "\n");
if (dfa_stats.num_phis)
- fprintf (file, "Average number of arguments per PHI node: %.1f (max: %d)\n",
+ fprintf (file, "Average number of arguments per PHI node: %.1f (max: %ld)\n",
(float) dfa_stats.num_phi_args / (float) dfa_stats.num_phis,
- dfa_stats.max_num_phi_args);
+ (long) dfa_stats.max_num_phi_args);
fprintf (file, "\n");
}
DFA_STATS_P. */
static void
-collect_dfa_stats (struct dfa_stats_d *dfa_stats_p)
+collect_dfa_stats (struct dfa_stats_d *dfa_stats_p ATTRIBUTE_UNUSED)
{
- struct pointer_set_t *pset;
basic_block bb;
- block_stmt_iterator i;
+ referenced_var_iterator vi;
+ tree var;
gcc_assert (dfa_stats_p);
memset ((void *)dfa_stats_p, 0, sizeof (struct dfa_stats_d));
- /* Walk all the trees in the function counting references. Start at
- basic block 0, but don't stop at block boundaries. */
- pset = pointer_set_create ();
-
- for (i = bsi_start (BASIC_BLOCK (0)); !bsi_end_p (i); bsi_next (&i))
- walk_tree (bsi_stmt_ptr (i), collect_dfa_stats_r, (void *) dfa_stats_p,
- pset);
-
- pointer_set_destroy (pset);
+ /* Count all the variable annotations. */
+ FOR_EACH_REFERENCED_VAR (var, vi)
+ if (var_ann (var))
+ dfa_stats_p->num_var_anns++;
+ /* Walk all the statements in the function counting references. */
FOR_EACH_BB (bb)
{
- tree phi;
- for (phi = phi_nodes (bb); phi; phi = PHI_CHAIN (phi))
+ gimple_stmt_iterator si;
+
+ for (si = gsi_start_phis (bb); !gsi_end_p (si); gsi_next (&si))
{
+ gimple phi = gsi_stmt (si);
dfa_stats_p->num_phis++;
- dfa_stats_p->num_phi_args += PHI_NUM_ARGS (phi);
- if (PHI_NUM_ARGS (phi) > dfa_stats_p->max_num_phi_args)
- dfa_stats_p->max_num_phi_args = PHI_NUM_ARGS (phi);
+ dfa_stats_p->num_phi_args += gimple_phi_num_args (phi);
+ if (gimple_phi_num_args (phi) > dfa_stats_p->max_num_phi_args)
+ dfa_stats_p->max_num_phi_args = gimple_phi_num_args (phi);
}
- }
-}
-
-
-/* Callback for walk_tree to collect DFA statistics for a tree and its
- children. */
-
-static tree
-collect_dfa_stats_r (tree *tp, int *walk_subtrees ATTRIBUTE_UNUSED,
- void *data)
-{
- tree t = *tp;
- struct dfa_stats_d *dfa_stats_p = (struct dfa_stats_d *)data;
- if (t->common.ann)
- {
- switch (ann_type (t->common.ann))
+ for (si = gsi_start_bb (bb); !gsi_end_p (si); gsi_next (&si))
{
- case STMT_ANN:
- {
- dfa_stats_p->num_stmt_anns++;
- dfa_stats_p->num_defs += NUM_SSA_OPERANDS (t, SSA_OP_DEF);
- dfa_stats_p->num_uses += NUM_SSA_OPERANDS (t, SSA_OP_USE);
- dfa_stats_p->num_v_may_defs += NUM_SSA_OPERANDS (t, SSA_OP_VMAYDEF);
- dfa_stats_p->num_vuses += NUM_SSA_OPERANDS (t, SSA_OP_VUSE);
- dfa_stats_p->num_v_must_defs +=
- NUM_SSA_OPERANDS (t, SSA_OP_VMUSTDEF);
- break;
- }
-
- case VAR_ANN:
- dfa_stats_p->num_var_anns++;
- break;
-
- default:
- break;
+ gimple stmt = gsi_stmt (si);
+ dfa_stats_p->num_defs += NUM_SSA_OPERANDS (stmt, SSA_OP_DEF);
+ dfa_stats_p->num_uses += NUM_SSA_OPERANDS (stmt, SSA_OP_USE);
+ dfa_stats_p->num_vdefs += gimple_vdef (stmt) ? 1 : 0;
+ dfa_stats_p->num_vuses += gimple_vuse (stmt) ? 1 : 0;
}
}
-
- return NULL;
}
the function. */
static tree
-find_vars_r (tree *tp, int *walk_subtrees, void *data)
+find_vars_r (tree *tp, int *walk_subtrees, void *data ATTRIBUTE_UNUSED)
{
- struct walk_state *walk_state = (struct walk_state *) data;
+ /* If we are reading the lto info back in, we need to rescan the
+ referenced vars. */
+ if (TREE_CODE (*tp) == SSA_NAME)
+ add_referenced_var (SSA_NAME_VAR (*tp));
/* If T is a regular variable that the optimizers are interested
in, add it to the list of variables. */
- if (SSA_VAR_P (*tp))
- add_referenced_var (*tp, walk_state);
+ else if (SSA_VAR_P (*tp))
+ add_referenced_var (*tp);
/* Type, _DECL and constant nodes have no interesting children.
Ignore them. */
return NULL_TREE;
}
+/* Find referenced variables in STMT. In contrast with
+ find_new_referenced_vars, this function will not mark newly found
+ variables for renaming. */
-/* Lookup UID in the referenced_vars hashtable and return the associated
- variable or NULL if it is not there. */
-
-tree
-referenced_var_lookup_if_exists (unsigned int uid)
+void
+find_referenced_vars_in (gimple stmt)
{
- struct int_tree_map *h, in;
- in.uid = uid;
- h = htab_find_with_hash (referenced_vars, &in, uid);
- if (h)
- return h->to;
- return NULL_TREE;
+ size_t i;
+
+ if (gimple_code (stmt) != GIMPLE_PHI)
+ {
+ for (i = 0; i < gimple_num_ops (stmt); i++)
+ walk_tree (gimple_op_ptr (stmt, i), find_vars_r, NULL, NULL);
+ }
+ else
+ {
+ walk_tree (gimple_phi_result_ptr (stmt), find_vars_r, NULL, NULL);
+
+ for (i = 0; i < gimple_phi_num_args (stmt); i++)
+ {
+ tree arg = gimple_phi_arg_def (stmt, i);
+ walk_tree (&arg, find_vars_r, NULL, NULL);
+ }
+ }
}
+
/* Lookup UID in the referenced_vars hashtable and return the associated
variable. */
tree
referenced_var_lookup (unsigned int uid)
{
- struct int_tree_map *h, in;
+ tree h;
+ struct tree_decl_minimal in;
in.uid = uid;
- h = htab_find_with_hash (referenced_vars, &in, uid);
+ h = (tree) htab_find_with_hash (gimple_referenced_vars (cfun), &in, uid);
gcc_assert (h || uid == 0);
- if (h)
- return h->to;
- return NULL_TREE;
+ return h;
}
-/* Insert the pair UID, TO into the referenced_vars hashtable. */
+/* Check if TO is in the referenced_vars hash table and insert it if not.
+ Return true if it required insertion. */
-static void
-referenced_var_insert (unsigned int uid, tree to)
+bool
+referenced_var_check_and_insert (tree to)
{
- struct int_tree_map *h;
- void **loc;
+ tree h, *loc;
+ struct tree_decl_minimal in;
+ unsigned int uid = DECL_UID (to);
+
+ in.uid = uid;
+ h = (tree) htab_find_with_hash (gimple_referenced_vars (cfun), &in, uid);
+ if (h)
+ {
+ /* DECL_UID has already been entered in the table. Verify that it is
+ the same entry as TO. See PR 27793. */
+ gcc_assert (h == to);
+ return false;
+ }
+
+ loc = (tree *) htab_find_slot_with_hash (gimple_referenced_vars (cfun),
+ &in, uid, INSERT);
+ *loc = to;
+ return true;
+}
+
+/* Lookup VAR UID in the default_defs hashtable and return the associated
+ variable. */
- h = ggc_alloc (sizeof (struct int_tree_map));
- h->uid = uid;
- h->to = to;
- loc = htab_find_slot_with_hash (referenced_vars, h, uid, INSERT);
- *(struct int_tree_map **) loc = h;
+tree
+gimple_default_def (struct function *fn, tree var)
+{
+ struct tree_decl_minimal ind;
+ struct tree_ssa_name in;
+ gcc_assert (SSA_VAR_P (var));
+ in.var = (tree)&ind;
+ ind.uid = DECL_UID (var);
+ return (tree) htab_find_with_hash (DEFAULT_DEFS (fn), &in, DECL_UID (var));
}
-/* Remove the pair DECL_UID (TO), TO from the referenced vars
- hashtable. */
+/* Insert the pair VAR's UID, DEF into the default_defs hashtable. */
void
-referenced_var_remove (tree to)
+set_default_def (tree var, tree def)
{
- struct int_tree_map in;
- in.uid = DECL_UID (to);
- in.to = to;
- htab_remove_elt_with_hash (referenced_vars, &in, in.uid);
-}
+ struct tree_decl_minimal ind;
+ struct tree_ssa_name in;
+ void **loc;
+
+ gcc_assert (SSA_VAR_P (var));
+ in.var = (tree)&ind;
+ ind.uid = DECL_UID (var);
+ if (!def)
+ {
+ loc = htab_find_slot_with_hash (DEFAULT_DEFS (cfun), &in,
+ DECL_UID (var), INSERT);
+ gcc_assert (*loc);
+ htab_remove_elt (DEFAULT_DEFS (cfun), *loc);
+ return;
+ }
+ gcc_assert (TREE_CODE (def) == SSA_NAME && SSA_NAME_VAR (def) == var);
+ loc = htab_find_slot_with_hash (DEFAULT_DEFS (cfun), &in,
+ DECL_UID (var), INSERT);
-/* Add VAR to the list of dereferenced variables.
+ /* Default definition might be changed by tail call optimization. */
+ if (*loc)
+ SSA_NAME_IS_DEFAULT_DEF (*(tree *) loc) = false;
+ *(tree *) loc = def;
- WALK_STATE contains a hash table used to avoid adding the same
- variable more than once. Note that this function assumes that
- VAR is a valid SSA variable. If WALK_STATE is NULL, no
- duplicate checking is done. */
+ /* Mark DEF as the default definition for VAR. */
+ SSA_NAME_IS_DEFAULT_DEF (def) = true;
+}
-static void
-add_referenced_var (tree var, struct walk_state *walk_state)
+/* Add VAR to the list of referenced variables if it isn't already there. */
+
+bool
+add_referenced_var (tree var)
{
- void **slot;
var_ann_t v_ann;
v_ann = get_var_ann (var);
-
- if (walk_state)
- slot = htab_find_slot (walk_state->vars_found, (void *) var, INSERT);
- else
- slot = NULL;
-
- if (slot == NULL || *slot == NULL)
+ gcc_assert (DECL_P (var));
+
+ /* Insert VAR into the referenced_vars has table if it isn't present. */
+ if (referenced_var_check_and_insert (var))
{
- /* This is the first time we find this variable, add it to the
- REFERENCED_VARS array and annotate it with attributes that are
- intrinsic to the variable. */
- if (slot)
- *slot = (void *) var;
-
- referenced_var_insert (DECL_UID (var), var);
-
- /* Global variables are always call-clobbered. */
- if (is_global_var (var))
- mark_call_clobbered (var);
-
/* Scan DECL_INITIAL for pointer variables as they may contain
address arithmetic referencing the address of other
- variables. */
+ variables. As we are only interested in directly referenced
+ globals or referenced locals restrict this to initializers
+ than can refer to local variables. */
if (DECL_INITIAL (var)
- /* Initializers of external variables are not useful to the
- optimizers. */
- && !DECL_EXTERNAL (var)
- /* It's not necessary to walk the initial value of non-constant
- variables because it cannot be propagated by the
- optimizers. */
- && (TREE_CONSTANT (var) || TREE_READONLY (var)))
- walk_tree (&DECL_INITIAL (var), find_vars_r, walk_state, 0);
+ && DECL_CONTEXT (var) == current_function_decl)
+ walk_tree (&DECL_INITIAL (var), find_vars_r, NULL, 0);
+
+ return true;
+ }
+
+ return false;
+}
+
+/* Remove VAR from the list. */
+
+void
+remove_referenced_var (tree var)
+{
+ var_ann_t v_ann;
+ struct tree_decl_minimal in;
+ void **loc;
+ unsigned int uid = DECL_UID (var);
+
+ /* Preserve var_anns of globals. */
+ if (!is_global_var (var)
+ && (v_ann = var_ann (var)))
+ {
+ ggc_free (v_ann);
+ var->base.ann = NULL;
}
+ gcc_assert (DECL_P (var));
+ in.uid = uid;
+ loc = htab_find_slot_with_hash (gimple_referenced_vars (cfun), &in, uid,
+ NO_INSERT);
+ htab_clear_slot (gimple_referenced_vars (cfun), loc);
}
return var;
}
-/* Add a temporary variable to REFERENCED_VARS. This is similar to
- add_referenced_var, but is used by passes that need to add new temps to
- the REFERENCED_VARS array after the program has been scanned for
- variables. The variable will just receive a new UID and be added
- to the REFERENCED_VARS array without checking for duplicates. */
-
-void
-add_referenced_tmp_var (tree var)
-{
- add_referenced_var (var, NULL);
-}
-
-
-/* Mark all the non-SSA variables found in STMT's operands to be
- processed by update_ssa. */
+/* Mark all the naked symbols in STMT for SSA renaming. */
void
-mark_new_vars_to_rename (tree stmt)
+mark_symbols_for_renaming (gimple stmt)
{
+ tree op;
ssa_op_iter iter;
- tree val;
- bitmap vars_in_vops_to_rename;
- bool found_exposed_symbol = false;
- int v_may_defs_before, v_may_defs_after;
- int v_must_defs_before, v_must_defs_after;
-
- if (TREE_CODE (stmt) == PHI_NODE)
- return;
-
- vars_in_vops_to_rename = BITMAP_ALLOC (NULL);
-
- /* Before re-scanning the statement for operands, mark the existing
- virtual operands to be renamed again. We do this because when new
- symbols are exposed, the virtual operands that were here before due to
- aliasing will probably be removed by the call to get_stmt_operand.
- Therefore, we need to flag them to be renamed beforehand.
-
- We flag them in a separate bitmap because we don't really want to
- rename them if there are not any newly exposed symbols in the
- statement operands. */
- v_may_defs_before = NUM_SSA_OPERANDS (stmt, SSA_OP_VMAYDEF);
- v_must_defs_before = NUM_SSA_OPERANDS (stmt, SSA_OP_VMUSTDEF);
-
- FOR_EACH_SSA_TREE_OPERAND (val, stmt, iter,
- SSA_OP_VMAYDEF | SSA_OP_VUSE | SSA_OP_VMUSTDEF)
- {
- if (!DECL_P (val))
- val = SSA_NAME_VAR (val);
- bitmap_set_bit (vars_in_vops_to_rename, DECL_UID (val));
- }
- /* Now force an operand re-scan on the statement and mark any newly
- exposed variables. */
update_stmt (stmt);
- v_may_defs_after = NUM_SSA_OPERANDS (stmt, SSA_OP_VMAYDEF);
- v_must_defs_after = NUM_SSA_OPERANDS (stmt, SSA_OP_VMUSTDEF);
-
- FOR_EACH_SSA_TREE_OPERAND (val, stmt, iter, SSA_OP_ALL_OPERANDS)
- if (DECL_P (val))
- {
- found_exposed_symbol = true;
- mark_sym_for_renaming (val);
- }
-
- /* If we found any newly exposed symbols, or if there are fewer VDEF
- operands in the statement, add the variables we had set in
- VARS_IN_VOPS_TO_RENAME to VARS_TO_RENAME. We need to check for
- vanishing VDEFs because in those cases, the names that were formerly
- generated by this statement are not going to be available anymore. */
- if (found_exposed_symbol
- || v_may_defs_before > v_may_defs_after
- || v_must_defs_before > v_must_defs_after)
- mark_set_for_renaming (vars_in_vops_to_rename);
-
- BITMAP_FREE (vars_in_vops_to_rename);
+ /* Mark all the operands for renaming. */
+ FOR_EACH_SSA_TREE_OPERAND (op, stmt, iter, SSA_OP_ALL_OPERANDS)
+ if (DECL_P (op))
+ mark_sym_for_renaming (op);
}
-/* Find all variables within the gimplified statement that were not previously
- visible to the function and add them to the referenced variables list. */
+
+/* Find all variables within the gimplified statement that were not
+ previously visible to the function and add them to the referenced
+ variables list. */
static tree
find_new_referenced_vars_1 (tree *tp, int *walk_subtrees,
if (TREE_CODE (t) == VAR_DECL && !var_ann (t))
{
- add_referenced_tmp_var (t);
+ add_referenced_var (t);
mark_sym_for_renaming (t);
}
return NULL;
}
+
+/* Find any new referenced variables in STMT. */
+
void
-find_new_referenced_vars (tree *stmt_p)
+find_new_referenced_vars (gimple stmt)
{
- walk_tree (stmt_p, find_new_referenced_vars_1, NULL, NULL);
+ walk_gimple_op (stmt, find_new_referenced_vars_1, NULL);
}
-/* If REF is a COMPONENT_REF for a structure that can have sub-variables, and
- we know where REF is accessing, return the variable in REF that has the
- sub-variables. If the return value is not NULL, POFFSET will be the
- offset, in bits, of REF inside the return value, and PSIZE will be the
- size, in bits, of REF inside the return value. */
+/* If EXP is a handled component reference for a structure, return the
+ base variable. The access range is delimited by bit positions *POFFSET and
+ *POFFSET + *PMAX_SIZE. The access size is *PSIZE bits. If either
+ *PSIZE or *PMAX_SIZE is -1, they could not be determined. If *PSIZE
+ and *PMAX_SIZE are equal, the access is non-variable. */
tree
-okay_component_ref_for_subvars (tree ref, unsigned HOST_WIDE_INT *poffset,
- unsigned HOST_WIDE_INT *psize)
+get_ref_base_and_extent (tree exp, HOST_WIDE_INT *poffset,
+ HOST_WIDE_INT *psize,
+ HOST_WIDE_INT *pmax_size)
{
- tree result = NULL;
- HOST_WIDE_INT bitsize;
- HOST_WIDE_INT bitpos;
- tree offset;
- enum machine_mode mode;
- int unsignedp;
- int volatilep;
-
- gcc_assert (!SSA_VAR_P (ref));
- *poffset = 0;
- *psize = (unsigned int) -1;
-
- if (ref_contains_array_ref (ref))
- return result;
- ref = get_inner_reference (ref, &bitsize, &bitpos, &offset, &mode,
- &unsignedp, &volatilep, false);
- if (TREE_CODE (ref) == INDIRECT_REF)
- return result;
- else if (offset == NULL && bitsize != -1 && SSA_VAR_P (ref))
+ HOST_WIDE_INT bitsize = -1;
+ HOST_WIDE_INT maxsize = -1;
+ tree size_tree = NULL_TREE;
+ HOST_WIDE_INT bit_offset = 0;
+ bool seen_variable_array_ref = false;
+ bool seen_union = false;
+
+ /* First get the final access size from just the outermost expression. */
+ if (TREE_CODE (exp) == COMPONENT_REF)
+ size_tree = DECL_SIZE (TREE_OPERAND (exp, 1));
+ else if (TREE_CODE (exp) == BIT_FIELD_REF)
+ size_tree = TREE_OPERAND (exp, 1);
+ else
{
- *poffset = bitpos;
- *psize = bitsize;
- if (get_subvars_for_var (ref) != NULL)
- return ref;
+ enum machine_mode mode = TYPE_MODE (TREE_TYPE (exp));
+ if (mode == BLKmode)
+ size_tree = TYPE_SIZE (TREE_TYPE (exp));
+ else
+ bitsize = GET_MODE_BITSIZE (mode);
}
- else if (SSA_VAR_P (ref))
+ if (size_tree != NULL_TREE)
{
- if (get_subvars_for_var (ref) != NULL)
- return ref;
+ if (! host_integerp (size_tree, 1))
+ bitsize = -1;
+ else
+ bitsize = TREE_INT_CST_LOW (size_tree);
}
- return NULL_TREE;
+
+ /* Initially, maxsize is the same as the accessed element size.
+ In the following it will only grow (or become -1). */
+ maxsize = bitsize;
+
+ /* Compute cumulative bit-offset for nested component-refs and array-refs,
+ and find the ultimate containing object. */
+ while (1)
+ {
+ switch (TREE_CODE (exp))
+ {
+ case BIT_FIELD_REF:
+ bit_offset += TREE_INT_CST_LOW (TREE_OPERAND (exp, 2));
+ break;
+
+ case COMPONENT_REF:
+ {
+ tree field = TREE_OPERAND (exp, 1);
+ tree this_offset = component_ref_field_offset (exp);
+
+ if (TREE_CODE (TREE_TYPE (TREE_OPERAND (exp, 0))) == UNION_TYPE)
+ seen_union = true;
+
+ if (this_offset
+ && TREE_CODE (this_offset) == INTEGER_CST
+ && host_integerp (this_offset, 0))
+ {
+ HOST_WIDE_INT hthis_offset = TREE_INT_CST_LOW (this_offset);
+ hthis_offset *= BITS_PER_UNIT;
+ bit_offset += hthis_offset;
+ bit_offset += TREE_INT_CST_LOW (DECL_FIELD_BIT_OFFSET (field));
+ }
+ else
+ {
+ tree csize = TYPE_SIZE (TREE_TYPE (TREE_OPERAND (exp, 0)));
+ /* We need to adjust maxsize to the whole structure bitsize.
+ But we can subtract any constant offset seen so far,
+ because that would get us out of the structure otherwise. */
+ if (maxsize != -1 && csize && host_integerp (csize, 1))
+ maxsize = TREE_INT_CST_LOW (csize) - bit_offset;
+ else
+ maxsize = -1;
+ }
+ }
+ break;
+
+ case ARRAY_REF:
+ case ARRAY_RANGE_REF:
+ {
+ tree index = TREE_OPERAND (exp, 1);
+ tree low_bound, unit_size;
+
+ /* If the resulting bit-offset is constant, track it. */
+ if (TREE_CODE (index) == INTEGER_CST
+ && host_integerp (index, 0)
+ && (low_bound = array_ref_low_bound (exp),
+ host_integerp (low_bound, 0))
+ && (unit_size = array_ref_element_size (exp),
+ host_integerp (unit_size, 1)))
+ {
+ HOST_WIDE_INT hindex = TREE_INT_CST_LOW (index);
+
+ hindex -= TREE_INT_CST_LOW (low_bound);
+ hindex *= TREE_INT_CST_LOW (unit_size);
+ hindex *= BITS_PER_UNIT;
+ bit_offset += hindex;
+
+ /* An array ref with a constant index up in the structure
+ hierarchy will constrain the size of any variable array ref
+ lower in the access hierarchy. */
+ seen_variable_array_ref = false;
+ }
+ else
+ {
+ tree asize = TYPE_SIZE (TREE_TYPE (TREE_OPERAND (exp, 0)));
+ /* We need to adjust maxsize to the whole array bitsize.
+ But we can subtract any constant offset seen so far,
+ because that would get us outside of the array otherwise. */
+ if (maxsize != -1 && asize && host_integerp (asize, 1))
+ maxsize = TREE_INT_CST_LOW (asize) - bit_offset;
+ else
+ maxsize = -1;
+
+ /* Remember that we have seen an array ref with a variable
+ index. */
+ seen_variable_array_ref = true;
+ }
+ }
+ break;
+
+ case REALPART_EXPR:
+ break;
+
+ case IMAGPART_EXPR:
+ bit_offset += bitsize;
+ break;
+
+ case VIEW_CONVERT_EXPR:
+ /* ??? We probably should give up here and bail out. */
+ break;
+
+ default:
+ goto done;
+ }
+
+ exp = TREE_OPERAND (exp, 0);
+ }
+ done:
+
+ /* We need to deal with variable arrays ending structures such as
+ struct { int length; int a[1]; } x; x.a[d]
+ struct { struct { int a; int b; } a[1]; } x; x.a[d].a
+ struct { struct { int a[1]; } a[1]; } x; x.a[0][d], x.a[d][0]
+ where we do not know maxsize for variable index accesses to
+ the array. The simplest way to conservatively deal with this
+ is to punt in the case that offset + maxsize reaches the
+ base type boundary.
+
+ Unfortunately this is difficult to determine reliably when unions are
+ involved and so we are conservative in such cases.
+
+ FIXME: This approach may be too conservative, we probably want to at least
+ check that the union is the last field/element at its level or even
+ propagate the calculated offsets back up the access chain and check
+ there. */
+
+ if (seen_variable_array_ref
+ && (seen_union
+ || (maxsize != -1
+ && host_integerp (TYPE_SIZE (TREE_TYPE (exp)), 1)
+ && bit_offset + maxsize
+ == (signed) TREE_INT_CST_LOW (TYPE_SIZE (TREE_TYPE (exp))))))
+ maxsize = -1;
+
+ /* ??? Due to negative offsets in ARRAY_REF we can end up with
+ negative bit_offset here. We might want to store a zero offset
+ in this case. */
+ *poffset = bit_offset;
+ *psize = bitsize;
+ *pmax_size = maxsize;
+
+ return exp;
+}
+
+/* Returns true if STMT references an SSA_NAME that has
+ SSA_NAME_OCCURS_IN_ABNORMAL_PHI set, otherwise false. */
+
+bool
+stmt_references_abnormal_ssa_name (gimple stmt)
+{
+ ssa_op_iter oi;
+ use_operand_p use_p;
+
+ FOR_EACH_SSA_USE_OPERAND (use_p, stmt, oi, SSA_OP_USE)
+ {
+ if (SSA_NAME_OCCURS_IN_ABNORMAL_PHI (USE_FROM_PTR (use_p)))
+ return true;
+ }
+
+ return false;
}
+
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