/*
* Normalize the Returns of a graph by creating a new End block
* with One Return(Phi).
- * This is the prefered input for the if-conversion.
+ * This is the preferred input for the if-conversion.
*
* In pseudocode, it means:
*
/* look, if we have more than one return */
n = get_Block_n_cfgpreds(endbl);
+ assert(n > 0);
returns = alloca((n + 7) >> 3);
memset(returns, 0, (n + 7) >> 3);
for (n_rets = i = 0; i < n; ++i) {
ir_node *node = get_Block_cfgpred(endbl, i);
- if (get_irn_op(node) == op_Return) {
+ if (is_Return(node)) {
++n_rets;
set_bit(i);
/* save the return values and shuffle them */
for (k = 0; k < n_ret_vals; ++k)
- retvals[j + k*n_ret_vals] = get_irn_n(ret, k);
-
- ++j;
+ retvals[j + k*n_rets] = get_irn_n(ret, k);
set_Block_cfgpred(endbl, i, new_r_Bad(irg));
last_idx = i;
+
+ ++j;
}
}
* a new Block was added, so dominator, outs and loop are inconsistent,
* trouts and callee-state should be still valid
*/
- set_irg_dom_inconsistent(irg);
+ set_irg_doms_inconsistent(irg);
set_irg_outs_inconsistent(irg);
set_irg_loopinfo_state(current_ir_graph, loopinfo_cf_inconsistent);
}
/*
* Normalize the Returns of a graph by moving
* the Returns upwards as much as possible.
- * This might be prefered for code generation.
+ * This might be preferred for code generation.
*
* In pseudocode, it means:
*
ir_node *final = NULL;
ir_node **in;
ir_node *endbl = get_irg_end_block(irg);
+ ir_node *end;
- /* first, link all returns */
+ /*
+ * First, link all returns:
+ * These must be predecessors of the endblock.
+ * Place Returns that can be moved on list, all others
+ * on final.
+ */
n = get_Block_n_cfgpreds(endbl);
for (n_finals = n_rets = i = 0; i < n; ++i) {
ir_node *ret = get_Block_cfgpred(endbl, i);
- if (get_irn_op(ret) == op_Return && can_move_ret(ret)) {
+ if (is_Return(ret) && can_move_ret(ret)) {
/*
* Ok, all conditions met, we can move this Return, put it
* on our work list.
* new Returns), than we check if a newly created Return can be moved even further.
* If yes, we simply add it to our work list, else to the final list.
*/
+ end = get_irg_end(irg);
n_ret_vals = get_irn_arity(list);
in = alloca(sizeof(*in) * n_ret_vals);
while (list) {
ir_node *ret = list;
ir_node *block = get_nodes_block(ret);
+ ir_node *phiM;
list = get_irn_link(ret);
--n_rets;
n = get_Block_n_cfgpreds(block);
for (i = 0; i < n; ++i) {
- ir_node *jmp = get_Block_cfgpred(block, i);
- ir_node *new_bl = get_nodes_block(jmp);
- ir_node *new_ret;
+ ir_node *jmp = get_Block_cfgpred(block, i);
+ ir_node *new_bl, *new_ret;
+
+ if (get_irn_op(jmp) != op_Jmp)
+ continue;
+
+ new_bl = get_nodes_block(jmp);
/* create the in-array for the new Ret */
for (j = 0; j < n_ret_vals; ++j) {
ir_node *pred = get_irn_n(ret, j);
- in[j] = is_Phi(pred) ? get_Phi_pred(pred, i) : pred;
+ in[j] = (is_Phi(pred) && get_nodes_block(pred) == block) ? get_Phi_pred(pred, i) : pred;
}
new_ret = new_r_Return(irg, new_bl, in[0], n_ret_vals - 1, &in[1]);
- if (can_move_ret(new_ret)) {
- set_irn_link(new_ret, list);
- list = new_ret;
- ++n_rets;
+ if (! is_Bad(new_ret)) {
+ /*
+ * The newly created node might be bad, if we
+ * create it in a block with only Bad predecessors.
+ * In that case ignore this block.
+ *
+ * We could even kill the jmp then ...
+ */
+ if (can_move_ret(new_ret)) {
+ set_irn_link(new_ret, list);
+ list = new_ret;
+ ++n_rets;
+ }
+ else {
+ set_irn_link(new_ret, final);
+ final = new_ret;
+ ++n_finals;
+ }
}
- else {
- set_irn_link(new_ret, final);
- final = new_ret;
- ++n_finals;
+
+ /* remove the Jmp, we have placed a Return here */
+ exchange(jmp, new_r_Bad(irg));
+ }
+
+ /*
+ * if the memory of the old Return is a PhiM, remove it
+ * from the keep-alives, or it will keep the block which
+ * will crash the dominator algorithm.
+ */
+ phiM = get_Return_mem(ret);
+ if (is_Phi(phiM)) {
+ n = get_End_n_keepalives(end);
+ for (i = 0; i < n; ++i) {
+ if (get_End_keepalive(end, i) == phiM) {
+ set_End_keepalive(end, i, new_r_Bad(irg));
+ break;
+ }
}
}
}
exchange(endbl, new_r_Block(irg, n_finals, in));
- /* the end block is not automatically skiped, so do it here */
+ /* the end block is not automatically skipped, so do it here */
set_irg_end_block(irg, skip_Id(get_irg_end_block(irg)));
/* Invalidate analysis information:
- * Blocks become dead and new Eeturns were deleted, so dominator, outs and loop are inconsistent,
+ * Blocks become dead and new Returns were deleted, so dominator, outs and loop are inconsistent,
* trouts and callee-state should be still valid
*/
- set_irg_dom_inconsistent(irg);
+ set_irg_doms_inconsistent(irg);
set_irg_outs_inconsistent(irg);
set_irg_loopinfo_state(current_ir_graph, loopinfo_cf_inconsistent);
}