void remove_tuples(ir_graph *irg)
{
bool changed = false;
irg_walk_graph(irg, exchange_tuple_projs, NULL, &changed);
/* remove Tuples only held by keep-alive edges */
ir_node *end = get_irg_end(irg);
for (int i = get_End_n_keepalives(end); i-- > 0; ) {
ir_node *irn = get_End_keepalive(end, i);
if (is_Tuple(irn)) {
remove_End_n(end, i);
changed = true;
}
}
confirm_irg_properties(irg, changed
? IR_GRAPH_PROPERTIES_CONTROL_FLOW | IR_GRAPH_PROPERTY_ONE_RETURN
| IR_GRAPH_PROPERTY_MANY_RETURNS | IR_GRAPH_PROPERTY_NO_BADS
: IR_GRAPH_PROPERTIES_ALL);
add_irg_properties(irg, IR_GRAPH_PROPERTY_NO_TUPLES);
}
/*
* Normalize the Returns of a graph by creating a new End block
* with One Return(Phi).
* This is the preferred input for the if-conversion.
*
* In pseudocode, it means:
*
* if (a)
* return b;
* else
* return c;
*
* is transformed into
*
* if (a)
* res = b;
* else
* res = c;
* return res;
*/
void normalize_one_return(ir_graph *irg)
{
ir_node *endbl = get_irg_end_block(irg);
ir_entity *entity = get_irg_entity(irg);
ir_type *type = get_entity_type(entity);
int n_ret_vals = get_method_n_ress(type) + 1;
int n_rets = 0;
bool filter_dbgi = false;
dbg_info *combined_dbgi = NULL;
int i, j, k, n, last_idx;
ir_node **in, **retvals, **endbl_in;
ir_node *block;
/* look, if we have more than one return */
n = get_Block_n_cfgpreds(endbl);
if (n <= 0) {
/* The end block has no predecessors, we have an endless
loop. In that case, no returns exists. */
confirm_irg_properties(irg, IR_GRAPH_PROPERTIES_ALL);
add_irg_properties(irg, IR_GRAPH_PROPERTY_ONE_RETURN);
return;
}
unsigned *const returns = rbitset_alloca(n);
for (i = 0; i < n; ++i) {
ir_node *node = get_Block_cfgpred(endbl, i);
if (is_Return(node)) {
dbg_info *dbgi = get_irn_dbg_info(node);
if (dbgi != NULL && dbgi != combined_dbgi) {
if (filter_dbgi) {
combined_dbgi = NULL;
} else {
combined_dbgi = dbgi;
filter_dbgi = true;
}
}
++n_rets;
rbitset_set(returns, i);
}
}
if (n_rets <= 1) {
confirm_irg_properties(irg, IR_GRAPH_PROPERTIES_ALL);
add_irg_properties(irg, IR_GRAPH_PROPERTY_ONE_RETURN);
return;
}
in = ALLOCAN(ir_node*, MAX(n_rets, n_ret_vals));
retvals = ALLOCAN(ir_node*, n_rets * n_ret_vals);
endbl_in = ALLOCAN(ir_node*, n);
last_idx = 0;
for (j = i = 0; i < n; ++i) {
ir_node *ret = get_Block_cfgpred(endbl, i);
if (rbitset_is_set(returns, i)) {
ir_node *block = get_nodes_block(ret);
/* create a new Jmp for every Ret and place the in in */
in[j] = new_r_Jmp(block);
/* save the return values and shuffle them */
for (k = 0; k < n_ret_vals; ++k)
retvals[j + k*n_rets] = get_irn_n(ret, k);
++j;
} else {
endbl_in[last_idx++] = ret;
}
}
/* ok, create a new block with all created in's */
block = new_r_Block(irg, n_rets, in);
/* now create the Phi nodes */
for (j = i = 0; i < n_ret_vals; ++i, j += n_rets) {
ir_mode *mode = get_irn_mode(retvals[j]);
in[i] = new_r_Phi(block, n_rets, &retvals[j], mode);
}
endbl_in[last_idx++] = new_rd_Return(combined_dbgi, block, in[0], n_ret_vals-1, &in[1]);
set_irn_in(endbl, last_idx, endbl_in);
/* invalidate analysis information:
* a new Block was added, so dominator, outs and loop are inconsistent,
* trouts and callee-state should be still valid */
confirm_irg_properties(irg,
IR_GRAPH_PROPERTY_NO_BADS
| IR_GRAPH_PROPERTY_NO_TUPLES
| IR_GRAPH_PROPERTY_NO_CRITICAL_EDGES
| IR_GRAPH_PROPERTY_NO_UNREACHABLE_CODE
| IR_GRAPH_PROPERTY_CONSISTENT_ENTITY_USAGE);
add_irg_properties(irg, IR_GRAPH_PROPERTY_ONE_RETURN);
}
