1.1 --- a/src/share/vm/opto/macro.cpp Fri Jun 03 22:31:43 2011 -0700
1.2 +++ b/src/share/vm/opto/macro.cpp Sat Jun 04 10:36:22 2011 -0700
1.3 @@ -1693,25 +1693,31 @@
1.4 OptoRuntime::new_array_Java());
1.5 }
1.6
1.7 -
1.8 -// we have determined that this lock/unlock can be eliminated, we simply
1.9 -// eliminate the node without expanding it.
1.10 -//
1.11 -// Note: The membar's associated with the lock/unlock are currently not
1.12 -// eliminated. This should be investigated as a future enhancement.
1.13 -//
1.14 -bool PhaseMacroExpand::eliminate_locking_node(AbstractLockNode *alock) {
1.15 -
1.16 +//-----------------------mark_eliminated_locking_nodes-----------------------
1.17 +// During EA obj may point to several objects but after few ideal graph
1.18 +// transformations (CCP) it may point to only one non escaping object
1.19 +// (but still using phi), corresponding locks and unlocks will be marked
1.20 +// for elimination. Later obj could be replaced with a new node (new phi)
1.21 +// and which does not have escape information. And later after some graph
1.22 +// reshape other locks and unlocks (which were not marked for elimination
1.23 +// before) are connected to this new obj (phi) but they still will not be
1.24 +// marked for elimination since new obj has no escape information.
1.25 +// Mark all associated (same box and obj) lock and unlock nodes for
1.26 +// elimination if some of them marked already.
1.27 +void PhaseMacroExpand::mark_eliminated_locking_nodes(AbstractLockNode *alock) {
1.28 if (!alock->is_eliminated()) {
1.29 - return false;
1.30 + return;
1.31 }
1.32 - if (alock->is_Lock() && !alock->is_coarsened()) {
1.33 + if (!alock->is_coarsened()) { // Eliminated by EA
1.34 // Create new "eliminated" BoxLock node and use it
1.35 // in monitor debug info for the same object.
1.36 BoxLockNode* oldbox = alock->box_node()->as_BoxLock();
1.37 Node* obj = alock->obj_node();
1.38 if (!oldbox->is_eliminated()) {
1.39 BoxLockNode* newbox = oldbox->clone()->as_BoxLock();
1.40 + // Note: BoxLock node is marked eliminated only here
1.41 + // and it is used to indicate that all associated lock
1.42 + // and unlock nodes are marked for elimination.
1.43 newbox->set_eliminated();
1.44 transform_later(newbox);
1.45 // Replace old box node with new box for all users
1.46 @@ -1720,22 +1726,14 @@
1.47
1.48 bool next_edge = true;
1.49 Node* u = oldbox->raw_out(i);
1.50 - if (u == alock) {
1.51 - i++;
1.52 - continue; // It will be removed below
1.53 - }
1.54 - if (u->is_Lock() &&
1.55 - u->as_Lock()->obj_node() == obj &&
1.56 - // oldbox could be referenced in debug info also
1.57 - u->as_Lock()->box_node() == oldbox) {
1.58 - assert(u->as_Lock()->is_eliminated(), "sanity");
1.59 + if (u->is_AbstractLock() &&
1.60 + u->as_AbstractLock()->obj_node() == obj &&
1.61 + u->as_AbstractLock()->box_node() == oldbox) {
1.62 + // Mark all associated locks and unlocks.
1.63 + u->as_AbstractLock()->set_eliminated();
1.64 _igvn.hash_delete(u);
1.65 u->set_req(TypeFunc::Parms + 1, newbox);
1.66 next_edge = false;
1.67 -#ifdef ASSERT
1.68 - } else if (u->is_Unlock() && u->as_Unlock()->obj_node() == obj) {
1.69 - assert(u->as_Unlock()->is_eliminated(), "sanity");
1.70 -#endif
1.71 }
1.72 // Replace old box in monitor debug info.
1.73 if (u->is_SafePoint() && u->as_SafePoint()->jvms()) {
1.74 @@ -1761,8 +1759,27 @@
1.75 if (next_edge) i++;
1.76 } // for (uint i = 0; i < oldbox->outcnt();)
1.77 } // if (!oldbox->is_eliminated())
1.78 - } // if (alock->is_Lock() && !lock->is_coarsened())
1.79 + } // if (!alock->is_coarsened())
1.80 +}
1.81
1.82 +// we have determined that this lock/unlock can be eliminated, we simply
1.83 +// eliminate the node without expanding it.
1.84 +//
1.85 +// Note: The membar's associated with the lock/unlock are currently not
1.86 +// eliminated. This should be investigated as a future enhancement.
1.87 +//
1.88 +bool PhaseMacroExpand::eliminate_locking_node(AbstractLockNode *alock) {
1.89 +
1.90 + if (!alock->is_eliminated()) {
1.91 + return false;
1.92 + }
1.93 +#ifdef ASSERT
1.94 + if (alock->is_Lock() && !alock->is_coarsened()) {
1.95 + // Check that new "eliminated" BoxLock node is created.
1.96 + BoxLockNode* oldbox = alock->box_node()->as_BoxLock();
1.97 + assert(oldbox->is_eliminated(), "should be done already");
1.98 + }
1.99 +#endif
1.100 CompileLog* log = C->log();
1.101 if (log != NULL) {
1.102 log->head("eliminate_lock lock='%d'",
1.103 @@ -2145,6 +2162,15 @@
1.104 if (C->macro_count() == 0)
1.105 return false;
1.106 // First, attempt to eliminate locks
1.107 + int cnt = C->macro_count();
1.108 + for (int i=0; i < cnt; i++) {
1.109 + Node *n = C->macro_node(i);
1.110 + if (n->is_AbstractLock()) { // Lock and Unlock nodes
1.111 + // Before elimination mark all associated (same box and obj)
1.112 + // lock and unlock nodes.
1.113 + mark_eliminated_locking_nodes(n->as_AbstractLock());
1.114 + }
1.115 + }
1.116 bool progress = true;
1.117 while (progress) {
1.118 progress = false;
