--- a/hotspot/src/share/vm/opto/loopTransform.cpp Fri May 29 12:49:31 2015 +0200
+++ b/hotspot/src/share/vm/opto/loopTransform.cpp Fri May 29 16:09:16 2015 +0200
@@ -1582,13 +1582,36 @@
if (opc != ReductionNode::opcode(opc, def_node->bottom_type()->basic_type())) {
if (!def_node->is_reduction()) { // Not marked yet
// To be a reduction, the arithmetic node must have the phi as input and provide a def to it
+ bool ok = false;
for (unsigned j = 1; j < def_node->req(); j++) {
Node* in = def_node->in(j);
if (in == phi) {
- def_node->add_flag(Node::Flag_is_reduction);
+ ok = true;
break;
}
}
+
+ // do nothing if we did not match the initial criteria
+ if (ok == false) {
+ continue;
+ }
+
+ // The result of the reduction must not be used in the loop
+ for (DUIterator_Fast imax, i = def_node->fast_outs(imax); i < imax && ok; i++) {
+ Node* u = def_node->fast_out(i);
+ if (has_ctrl(u) && !loop->is_member(get_loop(get_ctrl(u)))) {
+ continue;
+ }
+ if (u == phi) {
+ continue;
+ }
+ ok = false;
+ }
+
+ // iff the uses conform
+ if (ok) {
+ def_node->add_flag(Node::Flag_is_reduction);
+ }
}
}
}