src/hotspot/share/gc/shenandoah/shenandoahBarrierSet.cpp

rev 56771 : 8233339: Shenandoah: Centralize load barrier decisions into ShenandoahBarrierSet

@@ -25,10 +25,11 @@
 #include "gc/shenandoah/shenandoahAsserts.hpp"
 #include "gc/shenandoah/shenandoahBarrierSet.hpp"
 #include "gc/shenandoah/shenandoahBarrierSetClone.inline.hpp"
 #include "gc/shenandoah/shenandoahBarrierSetAssembler.hpp"
 #include "gc/shenandoah/shenandoahCollectorPolicy.hpp"
+#include "gc/shenandoah/shenandoahConcurrentRoots.hpp"
 #include "gc/shenandoah/shenandoahHeap.inline.hpp"
 #include "gc/shenandoah/shenandoahHeuristics.hpp"
 #include "gc/shenandoah/shenandoahTraversalGC.hpp"
 #include "memory/iterator.inline.hpp"
 #include "runtime/interfaceSupport.inline.hpp"

@@ -69,10 +70,40 @@
 
 bool ShenandoahBarrierSet::is_aligned(HeapWord* hw) {
   return true;
 }
 
+bool ShenandoahBarrierSet::need_load_reference_barrier(DecoratorSet decorators, BasicType type) {
+  if (!ShenandoahLoadRefBarrier) return false;
+  // Only needed for references
+  if (!is_reference_type(type)) return false;
+  return true;
+}
+
+bool ShenandoahBarrierSet::use_native_load_reference_barrier(DecoratorSet decorators, BasicType type) {
+  assert(need_load_reference_barrier(decorators, type), "Why ask?");
+  assert(is_reference_type(type), "Why we here?");
+  // Native load reference barrier is only needed for concurrent root processing
+  if (!ShenandoahConcurrentRoots::can_do_concurrent_roots()) {
+    return false;
+  }
+
+  return (decorators & IN_NATIVE) != 0;
+}
+
+bool ShenandoahBarrierSet::need_keep_alive_barrier(DecoratorSet decorators,BasicType type) {
+  if (!ShenandoahKeepAliveBarrier) return false;
+  // Only needed for references
+  if (!is_reference_type(type)) return false;
+
+  bool keep_alive = (decorators & AS_NO_KEEPALIVE) == 0;
+  bool unknown = (decorators & ON_UNKNOWN_OOP_REF) != 0;
+  bool is_traversal_mode = ShenandoahHeap::heap()->is_traversal_mode();
+  bool on_weak_ref = (decorators & (ON_WEAK_OOP_REF | ON_PHANTOM_OOP_REF)) != 0;
+  return (on_weak_ref || unknown) && (keep_alive || is_traversal_mode);
+}
+
 template <class T>
 inline void ShenandoahBarrierSet::inline_write_ref_field_pre(T* field, oop new_val) {
   shenandoah_assert_not_in_cset_loc_except(field, _heap->cancelled_gc());
   if (_heap->is_concurrent_mark_in_progress()) {
     T heap_oop = RawAccess<>::oop_load(field);