8227083: ZGC: C2: Generates on_weak barrier for WeakCompareAndSwap
Reviewed-by: neliasso, eosterlund
--- a/src/hotspot/share/gc/z/c2/zBarrierSetC2.cpp Tue Jul 02 12:10:18 2019 +0200
+++ b/src/hotspot/share/gc/z/c2/zBarrierSetC2.cpp Tue Jul 02 12:24:26 2019 +0200
@@ -1234,7 +1234,6 @@
Compile *C = phase->C;
PhaseIterGVN &igvn = phase->igvn();
LoadStoreNode* zclone = NULL;
- bool is_weak = false;
Node *in_ctrl = old_node->in(MemNode::Control);
Node *in_mem = old_node->in(MemNode::Memory);
@@ -1254,7 +1253,6 @@
if (can_simplify_cas(old_node)) {
break;
}
- is_weak = true;
zclone = new ZWeakCompareAndSwapPNode(in_ctrl, in_mem, in_adr, in_val, old_node->in(LoadStoreConditionalNode::ExpectedIn),
((CompareAndSwapNode*)old_node)->order());
adr_type = TypePtr::BOTTOM;
@@ -1285,7 +1283,7 @@
igvn.register_new_node_with_optimizer(load);
igvn.replace_node(old_node, zclone);
- Node *barrier = new LoadBarrierNode(C, NULL, in_mem, load, in_adr, is_weak);
+ Node *barrier = new LoadBarrierNode(C, NULL, in_mem, load, in_adr, false /* weak */);
Node *barrier_val = new ProjNode(barrier, LoadBarrierNode::Oop);
Node *barrier_ctrl = new ProjNode(barrier, LoadBarrierNode::Control);