7074017: Introduce MemBarAcquireLock/MemBarReleaseLock nodes for monitor enter/exit code paths

Summary: replace MemBarAcquire/MemBarRelease nodes on the monitor enter/exit code paths with new MemBarAcquireLock/MemBarReleaseLock nodes
Reviewed-by: kvn, twisti

hotspot/src/cpu/sparc/vm/sparc.ad

@@ -6605,8 +6605,7 @@ instruct membar_acquire() %{
 %}
 
 instruct membar_acquire_lock() %{
-  match(MemBarAcquire);
-  predicate(Matcher::prior_fast_lock(n));
+  match(MemBarAcquireLock);
   ins_cost(0);
 
   size(0);
@@ -6626,8 +6625,7 @@ instruct membar_release() %{
 %}
 
 instruct membar_release_lock() %{
-  match(MemBarRelease);
-  predicate(Matcher::post_fast_unlock(n));
+  match(MemBarReleaseLock);
   ins_cost(0);
 
   size(0);

hotspot/src/cpu/x86/vm/x86_32.ad

@@ -7805,8 +7805,7 @@ instruct membar_acquire() %{
 %}
 
 instruct membar_acquire_lock() %{
-  match(MemBarAcquire);
-  predicate(Matcher::prior_fast_lock(n));
+  match(MemBarAcquireLock);
   ins_cost(0);
 
   size(0);
@@ -7826,8 +7825,7 @@ instruct membar_release() %{
 %}
 
 instruct membar_release_lock() %{
-  match(MemBarRelease);
-  predicate(Matcher::post_fast_unlock(n));
+  match(MemBarReleaseLock);
   ins_cost(0);
 
   size(0);

hotspot/src/cpu/x86/vm/x86_64.ad

@@ -7375,8 +7375,7 @@ instruct membar_acquire()
 
 instruct membar_acquire_lock()
 %{
-  match(MemBarAcquire);
-  predicate(Matcher::prior_fast_lock(n));
+  match(MemBarAcquireLock);
   ins_cost(0);
 
   size(0);
@@ -7398,8 +7397,7 @@ instruct membar_release()
 
 instruct membar_release_lock()
 %{
-  match(MemBarRelease);
-  predicate(Matcher::post_fast_unlock(n));
+  match(MemBarReleaseLock);
   ins_cost(0);
 
   size(0);

hotspot/src/share/vm/adlc/formssel.cpp

@@ -624,6 +624,8 @@ bool InstructForm::is_wide_memory_kill(FormDict &globals) const {
 
   if( strcmp(_matrule->_opType,"MemBarRelease") == 0 ) return true;
   if( strcmp(_matrule->_opType,"MemBarAcquire") == 0 ) return true;
+  if( strcmp(_matrule->_opType,"MemBarReleaseLock") == 0 ) return true;
+  if( strcmp(_matrule->_opType,"MemBarAcquireLock") == 0 ) return true;
 
   return false;
 }
@@ -3941,6 +3943,8 @@ bool MatchRule::is_ideal_membar() const {
   return
     !strcmp(_opType,"MemBarAcquire"  ) ||
     !strcmp(_opType,"MemBarRelease"  ) ||
+    !strcmp(_opType,"MemBarAcquireLock") ||
+    !strcmp(_opType,"MemBarReleaseLock") ||
     !strcmp(_opType,"MemBarVolatile" ) ||
     !strcmp(_opType,"MemBarCPUOrder" ) ;
 }

hotspot/src/share/vm/opto/classes.hpp

@@ -161,8 +161,10 @@ macro(Mach)
 macro(MachProj)
 macro(MaxI)
 macro(MemBarAcquire)
+macro(MemBarAcquireLock)
 macro(MemBarCPUOrder)
 macro(MemBarRelease)
+macro(MemBarReleaseLock)
 macro(MemBarVolatile)
 macro(MergeMem)
 macro(MinI)

hotspot/src/share/vm/opto/graphKit.cpp

@@ -2856,7 +2856,7 @@ FastLockNode* GraphKit::shared_lock(Node* obj) {
   // lock has no side-effects, sets few values
   set_predefined_output_for_runtime_call(lock, mem, TypeRawPtr::BOTTOM);
 
-  insert_mem_bar(Op_MemBarAcquire);
+  insert_mem_bar(Op_MemBarAcquireLock);
 
   // Add this to the worklist so that the lock can be eliminated
   record_for_igvn(lock);
@@ -2889,7 +2889,7 @@ void GraphKit::shared_unlock(Node* box, Node* obj) {
   }
 
   // Memory barrier to avoid floating things down past the locked region
-  insert_mem_bar(Op_MemBarRelease);
+  insert_mem_bar(Op_MemBarReleaseLock);
 
   const TypeFunc *tf = OptoRuntime::complete_monitor_exit_Type();
   UnlockNode *unlock = new (C, tf->domain()->cnt()) UnlockNode(C, tf);

hotspot/src/share/vm/opto/macro.cpp

@@ -1816,9 +1816,9 @@ bool PhaseMacroExpand::eliminate_locking_node(AbstractLockNode *alock) {
   // The input to a Lock is merged memory, so extract its RawMem input
   // (unless the MergeMem has been optimized away.)
   if (alock->is_Lock()) {
-    // Seach for MemBarAcquire node and delete it also.
+    // Seach for MemBarAcquireLock node and delete it also.
     MemBarNode* membar = fallthroughproj->unique_ctrl_out()->as_MemBar();
-    assert(membar != NULL && membar->Opcode() == Op_MemBarAcquire, "");
+    assert(membar != NULL && membar->Opcode() == Op_MemBarAcquireLock, "");
     Node* ctrlproj = membar->proj_out(TypeFunc::Control);
     Node* memproj = membar->proj_out(TypeFunc::Memory);
     _igvn.replace_node(ctrlproj, fallthroughproj);
@@ -1833,11 +1833,11 @@ bool PhaseMacroExpand::eliminate_locking_node(AbstractLockNode *alock) {
     }
   }
 
-  // Seach for MemBarRelease node and delete it also.
+  // Seach for MemBarReleaseLock node and delete it also.
   if (alock->is_Unlock() && ctrl != NULL && ctrl->is_Proj() &&
       ctrl->in(0)->is_MemBar()) {
     MemBarNode* membar = ctrl->in(0)->as_MemBar();
-    assert(membar->Opcode() == Op_MemBarRelease &&
+    assert(membar->Opcode() == Op_MemBarReleaseLock &&
            mem->is_Proj() && membar == mem->in(0), "");
     _igvn.replace_node(fallthroughproj, ctrl);
     _igvn.replace_node(memproj_fallthrough, mem);

hotspot/src/share/vm/opto/matcher.cpp

@@ -2230,57 +2230,6 @@ void Matcher::validate_null_checks( ) {
   }
 }
 
-
-// Used by the DFA in dfa_sparc.cpp.  Check for a prior FastLock
-// acting as an Acquire and thus we don't need an Acquire here.  We
-// retain the Node to act as a compiler ordering barrier.
-bool Matcher::prior_fast_lock( const Node *acq ) {
-  Node *r = acq->in(0);
-  if( !r->is_Region() || r->req() <= 1 ) return false;
-  Node *proj = r->in(1);
-  if( !proj->is_Proj() ) return false;
-  Node *call = proj->in(0);
-  if( !call->is_Call() || call->as_Call()->entry_point() != OptoRuntime::complete_monitor_locking_Java() )
-    return false;
-
-  return true;
-}
-
-// Used by the DFA in dfa_sparc.cpp.  Check for a following FastUnLock
-// acting as a Release and thus we don't need a Release here.  We
-// retain the Node to act as a compiler ordering barrier.
-bool Matcher::post_fast_unlock( const Node *rel ) {
-  Compile *C = Compile::current();
-  assert( rel->Opcode() == Op_MemBarRelease, "" );
-  const MemBarReleaseNode *mem = (const MemBarReleaseNode*)rel;
-  DUIterator_Fast imax, i = mem->fast_outs(imax);
-  Node *ctrl = NULL;
-  while( true ) {
-    ctrl = mem->fast_out(i);            // Throw out-of-bounds if proj not found
-    assert( ctrl->is_Proj(), "only projections here" );
-    ProjNode *proj = (ProjNode*)ctrl;
-    if( proj->_con == TypeFunc::Control &&
-        !C->node_arena()->contains(ctrl) ) // Unmatched old-space only
-      break;
-    i++;
-  }
-  Node *iff = NULL;
-  for( DUIterator_Fast jmax, j = ctrl->fast_outs(jmax); j < jmax; j++ ) {
-    Node *x = ctrl->fast_out(j);
-    if( x->is_If() && x->req() > 1 &&
-        !C->node_arena()->contains(x) ) { // Unmatched old-space only
-      iff = x;
-      break;
-    }
-  }
-  if( !iff ) return false;
-  Node *bol = iff->in(1);
-  // The iff might be some random subclass of If or bol might be Con-Top
-  if (!bol->is_Bool())  return false;
-  assert( bol->req() > 1, "" );
-  return (bol->in(1)->Opcode() == Op_FastUnlock);
-}
-
 // Used by the DFA in dfa_xxx.cpp.  Check for a following barrier or
 // atomic instruction acting as a store_load barrier without any
 // intervening volatile load, and thus we don't need a barrier here.

hotspot/src/share/vm/opto/matcher.hpp

@@ -441,16 +441,6 @@ public:
     else { fatal("SoftMatchFailure is not allowed except in product"); }
   }
 
-  // Used by the DFA in dfa_sparc.cpp.  Check for a prior FastLock
-  // acting as an Acquire and thus we don't need an Acquire here.  We
-  // retain the Node to act as a compiler ordering barrier.
-  static bool prior_fast_lock( const Node *acq );
-
-  // Used by the DFA in dfa_sparc.cpp.  Check for a following
-  // FastUnLock acting as a Release and thus we don't need a Release
-  // here.  We retain the Node to act as a compiler ordering barrier.
-  static bool post_fast_unlock( const Node *rel );
-
   // Check for a following volatile memory barrier without an
   // intervening load and thus we don't need a barrier here.  We
   // retain the Node to act as a compiler ordering barrier.

hotspot/src/share/vm/opto/memnode.cpp

@@ -925,8 +925,9 @@ Node* MemNode::can_see_stored_value(Node* st, PhaseTransform* phase) const {
     // a synchronized region.
     while (current->is_Proj()) {
       int opc = current->in(0)->Opcode();
-      if ((final && opc == Op_MemBarAcquire) ||
-          opc == Op_MemBarRelease || opc == Op_MemBarCPUOrder) {
+      if ((final && (opc == Op_MemBarAcquire || opc == Op_MemBarAcquireLock)) ||
+          opc == Op_MemBarRelease || opc == Op_MemBarCPUOrder ||
+          opc == Op_MemBarReleaseLock) {
         Node* mem = current->in(0)->in(TypeFunc::Memory);
         if (mem->is_MergeMem()) {
           MergeMemNode* merge = mem->as_MergeMem();
@@ -2666,6 +2667,8 @@ MemBarNode* MemBarNode::make(Compile* C, int opcode, int atp, Node* pn) {
   switch (opcode) {
   case Op_MemBarAcquire:   return new(C, len) MemBarAcquireNode(C,  atp, pn);
   case Op_MemBarRelease:   return new(C, len) MemBarReleaseNode(C,  atp, pn);
+  case Op_MemBarAcquireLock: return new(C, len) MemBarAcquireLockNode(C,  atp, pn);
+  case Op_MemBarReleaseLock: return new(C, len) MemBarReleaseLockNode(C,  atp, pn);
   case Op_MemBarVolatile:  return new(C, len) MemBarVolatileNode(C, atp, pn);
   case Op_MemBarCPUOrder:  return new(C, len) MemBarCPUOrderNode(C, atp, pn);
   case Op_Initialize:      return new(C, len) InitializeNode(C,     atp, pn);

hotspot/src/share/vm/opto/memnode.hpp

@@ -879,7 +879,7 @@ public:
 
 // "Acquire" - no following ref can move before (but earlier refs can
 // follow, like an early Load stalled in cache).  Requires multi-cpu
-// visibility.  Inserted after a volatile load or FastLock.
+// visibility.  Inserted after a volatile load.
 class MemBarAcquireNode: public MemBarNode {
 public:
   MemBarAcquireNode(Compile* C, int alias_idx, Node* precedent)
@@ -889,7 +889,7 @@ public:
 
 // "Release" - no earlier ref can move after (but later refs can move
 // up, like a speculative pipelined cache-hitting Load).  Requires
-// multi-cpu visibility.  Inserted before a volatile store or FastUnLock.
+// multi-cpu visibility.  Inserted before a volatile store.
 class MemBarReleaseNode: public MemBarNode {
 public:
   MemBarReleaseNode(Compile* C, int alias_idx, Node* precedent)
@@ -897,6 +897,26 @@ public:
   virtual int Opcode() const;
 };
 
+// "Acquire" - no following ref can move before (but earlier refs can
+// follow, like an early Load stalled in cache).  Requires multi-cpu
+// visibility.  Inserted after a FastLock.
+class MemBarAcquireLockNode: public MemBarNode {
+public:
+  MemBarAcquireLockNode(Compile* C, int alias_idx, Node* precedent)
+    : MemBarNode(C, alias_idx, precedent) {}
+  virtual int Opcode() const;
+};
+
+// "Release" - no earlier ref can move after (but later refs can move
+// up, like a speculative pipelined cache-hitting Load).  Requires
+// multi-cpu visibility.  Inserted before a FastUnLock.
+class MemBarReleaseLockNode: public MemBarNode {
+public:
+  MemBarReleaseLockNode(Compile* C, int alias_idx, Node* precedent)
+    : MemBarNode(C, alias_idx, precedent) {}
+  virtual int Opcode() const;
+};
+
 // Ordering between a volatile store and a following volatile load.
 // Requires multi-CPU visibility?
 class MemBarVolatileNode: public MemBarNode {