static unsigned int
rename_ssa_copies (void)
{
var_map map;
basic_block bb;
gimple_stmt_iterator gsi;
tree var, part_var;
gimple stmt, phi;
unsigned x;
FILE *debug;
bool updated = false;
memset (&stats, 0, sizeof (stats));
if (dump_file && (dump_flags & TDF_DETAILS))
debug = dump_file;
else
debug = NULL;
map = init_var_map (num_ssa_names);
FOR_EACH_BB (bb)
{
/* Scan for real copies. */
for (gsi = gsi_start_bb (bb); !gsi_end_p (gsi); gsi_next (&gsi))
{
stmt = gsi_stmt (gsi);
if (gimple_assign_ssa_name_copy_p (stmt))
{
tree lhs = gimple_assign_lhs (stmt);
tree rhs = gimple_assign_rhs1 (stmt);
updated |= copy_rename_partition_coalesce (map, lhs, rhs, debug);
}
}
}
FOR_EACH_BB (bb)
{
/* Treat PHI nodes as copies between the result and each argument. */
for (gsi = gsi_start_phis (bb); !gsi_end_p (gsi); gsi_next (&gsi))
{
size_t i;
tree res;
phi = gsi_stmt (gsi);
res = gimple_phi_result (phi);
/* Do not process virtual SSA_NAMES. */
if (virtual_operand_p (res))
continue;
/* Make sure to only use the same partition for an argument
as the result but never the other way around. */
if (SSA_NAME_VAR (res)
&& !DECL_IGNORED_P (SSA_NAME_VAR (res)))
for (i = 0; i < gimple_phi_num_args (phi); i++)
{
tree arg = PHI_ARG_DEF (phi, i);
if (TREE_CODE (arg) == SSA_NAME)
updated |= copy_rename_partition_coalesce (map, res, arg,
debug);
}
/* Else if all arguments are in the same partition try to merge
it with the result. */
else
{
int all_p_same = -1;
int p = -1;
for (i = 0; i < gimple_phi_num_args (phi); i++)
{
tree arg = PHI_ARG_DEF (phi, i);
if (TREE_CODE (arg) != SSA_NAME)
{
all_p_same = 0;
break;
}
else if (all_p_same == -1)
{
p = partition_find (map->var_partition,
SSA_NAME_VERSION (arg));
all_p_same = 1;
}
else if (all_p_same == 1
&& p != partition_find (map->var_partition,
SSA_NAME_VERSION (arg)))
{
all_p_same = 0;
break;
}
}
if (all_p_same == 1)
updated |= copy_rename_partition_coalesce (map, res,
PHI_ARG_DEF (phi, 0),
debug);
}
}
}
if (debug)
dump_var_map (debug, map);
/* Now one more pass to make all elements of a partition share the same
root variable. */
for (x = 1; x < num_ssa_names; x++)
{
part_var = partition_to_var (map, x);
if (!part_var)
continue;
var = ssa_name (x);
if (SSA_NAME_VAR (var) == SSA_NAME_VAR (part_var))
continue;
if (debug)
{
fprintf (debug, "Coalesced ");
print_generic_expr (debug, var, TDF_SLIM);
fprintf (debug, " to ");
print_generic_expr (debug, part_var, TDF_SLIM);
fprintf (debug, "\n");
}
stats.coalesced++;
replace_ssa_name_symbol (var, SSA_NAME_VAR (part_var));
}
statistics_counter_event (cfun, "copies coalesced",
stats.coalesced);
delete_var_map (map);
return updated ? TODO_remove_unused_locals : 0;
}
static unsigned int
rename_ssa_copies (void)
{
var_map map;
basic_block bb;
gimple_stmt_iterator gsi;
tree var, part_var;
gimple stmt, phi;
unsigned x;
FILE *debug;
bool updated = false;
if (dump_file && (dump_flags & TDF_DETAILS))
debug = dump_file;
else
debug = NULL;
map = init_var_map (num_ssa_names);
FOR_EACH_BB (bb)
{
/* Scan for real copies. */
for (gsi = gsi_start_bb (bb); !gsi_end_p (gsi); gsi_next (&gsi))
{
stmt = gsi_stmt (gsi);
if (gimple_assign_ssa_name_copy_p (stmt))
{
tree lhs = gimple_assign_lhs (stmt);
tree rhs = gimple_assign_rhs1 (stmt);
updated |= copy_rename_partition_coalesce (map, lhs, rhs, debug);
}
}
}
FOR_EACH_BB (bb)
{
/* Treat PHI nodes as copies between the result and each argument. */
for (gsi = gsi_start_phis (bb); !gsi_end_p (gsi); gsi_next (&gsi))
{
size_t i;
tree res;
phi = gsi_stmt (gsi);
res = gimple_phi_result (phi);
/* Do not process virtual SSA_NAMES. */
if (!is_gimple_reg (SSA_NAME_VAR (res)))
continue;
for (i = 0; i < gimple_phi_num_args (phi); i++)
{
tree arg = gimple_phi_arg (phi, i)->def;
if (TREE_CODE (arg) == SSA_NAME)
updated |= copy_rename_partition_coalesce (map, res, arg, debug);
}
}
}
if (debug)
dump_var_map (debug, map);
/* Now one more pass to make all elements of a partition share the same
root variable. */
for (x = 1; x < num_ssa_names; x++)
{
part_var = partition_to_var (map, x);
if (!part_var)
continue;
var = ssa_name (x);
if (debug)
{
if (SSA_NAME_VAR (var) != SSA_NAME_VAR (part_var))
{
fprintf (debug, "Coalesced ");
print_generic_expr (debug, var, TDF_SLIM);
fprintf (debug, " to ");
print_generic_expr (debug, part_var, TDF_SLIM);
fprintf (debug, "\n");
}
}
replace_ssa_name_symbol (var, SSA_NAME_VAR (part_var));
}
delete_var_map (map);
return updated ? TODO_remove_unused_locals : 0;
}