static bool
can_propagate_from (gimple def_stmt)
{
use_operand_p use_p;
ssa_op_iter iter;
gcc_assert (is_gimple_assign (def_stmt));
/* If the rhs has side-effects we cannot propagate from it. */
if (gimple_has_volatile_ops (def_stmt))
return false;
/* If the rhs is a load we cannot propagate from it. */
if (TREE_CODE_CLASS (gimple_assign_rhs_code (def_stmt)) == tcc_reference
|| TREE_CODE_CLASS (gimple_assign_rhs_code (def_stmt)) == tcc_declaration)
return false;
/* Constants can be always propagated. */
if (is_gimple_min_invariant
(rhs_to_tree (TREE_TYPE (gimple_assign_lhs (def_stmt)), def_stmt)))
return true;
/* We cannot propagate ssa names that occur in abnormal phi nodes. */
FOR_EACH_SSA_USE_OPERAND (use_p, def_stmt, iter, SSA_OP_USE)
if (SSA_NAME_OCCURS_IN_ABNORMAL_PHI (USE_FROM_PTR (use_p)))
return false;
/* If the definition is a conversion of a pointer to a function type,
then we can not apply optimizations as some targets require
function pointers to be canonicalized and in this case this
optimization could eliminate a necessary canonicalization. */
if (is_gimple_assign (def_stmt)
&& (CONVERT_EXPR_CODE_P (gimple_assign_rhs_code (def_stmt))))
{
tree rhs = gimple_assign_rhs1 (def_stmt);
if (POINTER_TYPE_P (TREE_TYPE (rhs))
&& TREE_CODE (TREE_TYPE (TREE_TYPE (rhs))) == FUNCTION_TYPE)
return false;
}
return true;
}
static int
forward_propagate_into_cond (gimple_stmt_iterator *gsi_p)
{
gimple stmt = gsi_stmt (*gsi_p);
int did_something = 0;
do {
tree tmp = NULL_TREE;
tree cond = gimple_assign_rhs1 (stmt);
tree name, rhs0 = NULL_TREE, rhs1 = NULL_TREE;
gimple def_stmt;
bool single_use0_p = false, single_use1_p = false;
/* We can do tree combining on SSA_NAME and comparison expressions. */
if (COMPARISON_CLASS_P (cond)
&& TREE_CODE (TREE_OPERAND (cond, 0)) == SSA_NAME)
{
/* For comparisons use the first operand, that is likely to
simplify comparisons against constants. */
name = TREE_OPERAND (cond, 0);
def_stmt = get_prop_source_stmt (name, false, &single_use0_p);
if (def_stmt && can_propagate_from (def_stmt))
{
tree op1 = TREE_OPERAND (cond, 1);
rhs0 = rhs_to_tree (TREE_TYPE (op1), def_stmt);
tmp = combine_cond_expr_cond (TREE_CODE (cond), boolean_type_node,
rhs0, op1, !single_use0_p);
}
/* If that wasn't successful, try the second operand. */
if (tmp == NULL_TREE
&& TREE_CODE (TREE_OPERAND (cond, 1)) == SSA_NAME)
{
tree op0 = TREE_OPERAND (cond, 0);
name = TREE_OPERAND (cond, 1);
def_stmt = get_prop_source_stmt (name, false, &single_use1_p);
if (!def_stmt || !can_propagate_from (def_stmt))
return did_something;
rhs1 = rhs_to_tree (TREE_TYPE (op0), def_stmt);
tmp = combine_cond_expr_cond (TREE_CODE (cond), boolean_type_node,
op0, rhs1, !single_use1_p);
}
/* If that wasn't successful either, try both operands. */
if (tmp == NULL_TREE
&& rhs0 != NULL_TREE
&& rhs1 != NULL_TREE)
tmp = combine_cond_expr_cond (TREE_CODE (cond), boolean_type_node,
rhs0, fold_convert (TREE_TYPE (rhs0),
rhs1),
!(single_use0_p && single_use1_p));
}
else if (TREE_CODE (cond) == SSA_NAME)
{
name = cond;
def_stmt = get_prop_source_stmt (name, true, NULL);
if (def_stmt || !can_propagate_from (def_stmt))
return did_something;
rhs0 = gimple_assign_rhs1 (def_stmt);
tmp = combine_cond_expr_cond (NE_EXPR, boolean_type_node, rhs0,
build_int_cst (TREE_TYPE (rhs0), 0),
false);
}
if (tmp)
{
if (dump_file && tmp)
{
fprintf (dump_file, " Replaced '");
print_generic_expr (dump_file, cond, 0);
fprintf (dump_file, "' with '");
print_generic_expr (dump_file, tmp, 0);
fprintf (dump_file, "'\n");
}
gimple_assign_set_rhs_from_tree (gsi_p, unshare_expr (tmp));
stmt = gsi_stmt (*gsi_p);
update_stmt (stmt);
/* Remove defining statements. */
remove_prop_source_from_use (name, NULL);
if (is_gimple_min_invariant (tmp))
did_something = 2;
else if (did_something == 0)
did_something = 1;
/* Continue combining. */
continue;
}
break;
} while (1);
return did_something;
}
static int
forward_propagate_into_gimple_cond (gimple stmt)
{
int did_something = 0;
location_t loc = gimple_location (stmt);
do {
tree tmp = NULL_TREE;
tree name, rhs0 = NULL_TREE, rhs1 = NULL_TREE;
gimple def_stmt;
bool single_use0_p = false, single_use1_p = false;
enum tree_code code = gimple_cond_code (stmt);
/* We can do tree combining on SSA_NAME and comparison expressions. */
if (TREE_CODE_CLASS (gimple_cond_code (stmt)) == tcc_comparison
&& TREE_CODE (gimple_cond_lhs (stmt)) == SSA_NAME)
{
/* For comparisons use the first operand, that is likely to
simplify comparisons against constants. */
name = gimple_cond_lhs (stmt);
def_stmt = get_prop_source_stmt (name, false, &single_use0_p);
if (def_stmt && can_propagate_from (def_stmt))
{
tree op1 = gimple_cond_rhs (stmt);
rhs0 = rhs_to_tree (TREE_TYPE (op1), def_stmt);
tmp = combine_cond_expr_cond (loc, code, boolean_type_node, rhs0,
op1, !single_use0_p);
}
/* If that wasn't successful, try the second operand. */
if (tmp == NULL_TREE
&& TREE_CODE (gimple_cond_rhs (stmt)) == SSA_NAME)
{
tree op0 = gimple_cond_lhs (stmt);
name = gimple_cond_rhs (stmt);
def_stmt = get_prop_source_stmt (name, false, &single_use1_p);
if (!def_stmt || !can_propagate_from (def_stmt))
return did_something;
rhs1 = rhs_to_tree (TREE_TYPE (op0), def_stmt);
tmp = combine_cond_expr_cond (loc, code, boolean_type_node, op0,
rhs1, !single_use1_p);
}
/* If that wasn't successful either, try both operands. */
if (tmp == NULL_TREE
&& rhs0 != NULL_TREE
&& rhs1 != NULL_TREE)
tmp = combine_cond_expr_cond (loc, code, boolean_type_node, rhs0,
fold_convert_loc (loc,
TREE_TYPE (rhs0),
rhs1),
!(single_use0_p && single_use1_p));
}
if (tmp)
{
if (dump_file && tmp)
{
tree cond = build2 (gimple_cond_code (stmt),
boolean_type_node,
gimple_cond_lhs (stmt),
gimple_cond_rhs (stmt));
fprintf (dump_file, " Replaced '");
print_generic_expr (dump_file, cond, 0);
fprintf (dump_file, "' with '");
print_generic_expr (dump_file, tmp, 0);
fprintf (dump_file, "'\n");
}
gimple_cond_set_condition_from_tree (stmt, unshare_expr (tmp));
update_stmt (stmt);
/* Remove defining statements. */
remove_prop_source_from_use (name, NULL);
if (is_gimple_min_invariant (tmp))
did_something = 2;
else if (did_something == 0)
did_something = 1;
/* Continue combining. */
continue;
}
break;
} while (1);
return did_something;
}