# HG changeset patch
# User kvn
# Date 1266017256 28800
# Node ID 7b4415a18c8afb70569c8188db8a85f6154a8948
# Parent  95d21201c29ac4943b77287cd335294221304e97# Parent  c09ee209b65c742568e86da87f2335701423a445
Merge

diff -r c09ee209b65c -r 7b4415a18c8a .hgtags
--- a/.hgtags	Fri Feb 12 10:34:11 2010 -0800
+++ b/.hgtags	Fri Feb 12 15:27:36 2010 -0800
@@ -54,3 +54,5 @@
 455105fc81d941482f8f8056afaa7aa0949c9300 jdk7-b77
 e703499b4b51e3af756ae77c3d5e8b3058a14e4e jdk7-b78
 a5a6adfca6ecefb5894a848debabfe442ff50e25 jdk7-b79
+3003ddd1d4330b06cb4691ae74d600d3685899eb jdk7-b80
+1f9b07674480c224828852ffe137beea36b3cab5 jdk7-b81
diff -r c09ee209b65c -r 7b4415a18c8a make/hotspot_version
--- a/make/hotspot_version	Fri Feb 12 10:34:11 2010 -0800
+++ b/make/hotspot_version	Fri Feb 12 15:27:36 2010 -0800
@@ -35,7 +35,7 @@
 
 HS_MAJOR_VER=17
 HS_MINOR_VER=0
-HS_BUILD_NUMBER=07
+HS_BUILD_NUMBER=09
 
 JDK_MAJOR_VER=1
 JDK_MINOR_VER=7
diff -r c09ee209b65c -r 7b4415a18c8a src/cpu/sparc/vm/c1_LIRAssembler_sparc.cpp
--- a/src/cpu/sparc/vm/c1_LIRAssembler_sparc.cpp	Fri Feb 12 10:34:11 2010 -0800
+++ b/src/cpu/sparc/vm/c1_LIRAssembler_sparc.cpp	Fri Feb 12 15:27:36 2010 -0800
@@ -378,7 +378,7 @@
 
   int offset = code_offset();
 
-  if (compilation()->has_exception_handlers() || compilation()->env()->jvmti_can_post_exceptions()) {
+  if (compilation()->has_exception_handlers() || compilation()->env()->jvmti_can_post_on_exceptions()) {
     __ call(Runtime1::entry_for(Runtime1::handle_exception_id), relocInfo::runtime_call_type);
     __ delayed()->nop();
   }
diff -r c09ee209b65c -r 7b4415a18c8a src/cpu/x86/vm/c1_LIRAssembler_x86.cpp
--- a/src/cpu/x86/vm/c1_LIRAssembler_x86.cpp	Fri Feb 12 10:34:11 2010 -0800
+++ b/src/cpu/x86/vm/c1_LIRAssembler_x86.cpp	Fri Feb 12 15:27:36 2010 -0800
@@ -438,7 +438,7 @@
 
   // if the method does not have an exception handler, then there is
   // no reason to search for one
-  if (compilation()->has_exception_handlers() || compilation()->env()->jvmti_can_post_exceptions()) {
+  if (compilation()->has_exception_handlers() || compilation()->env()->jvmti_can_post_on_exceptions()) {
     // the exception oop and pc are in rax, and rdx
     // no other registers need to be preserved, so invalidate them
     __ invalidate_registers(false, true, true, false, true, true);
diff -r c09ee209b65c -r 7b4415a18c8a src/cpu/x86/vm/templateTable_x86_64.cpp
--- a/src/cpu/x86/vm/templateTable_x86_64.cpp	Fri Feb 12 10:34:11 2010 -0800
+++ b/src/cpu/x86/vm/templateTable_x86_64.cpp	Fri Feb 12 15:27:36 2010 -0800
@@ -3238,17 +3238,19 @@
     __ xorl(rcx, rcx); // use zero reg to clear memory (shorter code)
     __ store_klass_gap(rax, rcx);  // zero klass gap for compressed oops
     __ store_klass(rax, rsi);      // store klass last
+
+    {
+      SkipIfEqual skip(_masm, &DTraceAllocProbes, false);
+      // Trigger dtrace event for fastpath
+      __ push(atos); // save the return value
+      __ call_VM_leaf(
+           CAST_FROM_FN_PTR(address, SharedRuntime::dtrace_object_alloc), rax);
+      __ pop(atos); // restore the return value
+
+    }
     __ jmp(done);
   }
 
-  {
-    SkipIfEqual skip(_masm, &DTraceAllocProbes, false);
-    // Trigger dtrace event for fastpath
-    __ push(atos); // save the return value
-    __ call_VM_leaf(
-         CAST_FROM_FN_PTR(address, SharedRuntime::dtrace_object_alloc), rax);
-    __ pop(atos); // restore the return value
-  }
 
   // slow case
   __ bind(slow_case);
diff -r c09ee209b65c -r 7b4415a18c8a src/os/windows/vm/os_windows.cpp
--- a/src/os/windows/vm/os_windows.cpp	Fri Feb 12 10:34:11 2010 -0800
+++ b/src/os/windows/vm/os_windows.cpp	Fri Feb 12 15:27:36 2010 -0800
@@ -1,5 +1,5 @@
 /*
- * Copyright 1997-2009 Sun Microsystems, Inc.  All Rights Reserved.
+ * Copyright 1997-2010 Sun Microsystems, Inc.  All Rights Reserved.
  * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
  *
  * This code is free software; you can redistribute it and/or modify it
@@ -142,6 +142,9 @@
 }
 
 #ifndef _WIN64
+// previous UnhandledExceptionFilter, if there is one
+static LPTOP_LEVEL_EXCEPTION_FILTER prev_uef_handler = NULL;
+
 LONG WINAPI Handle_FLT_Exception(struct _EXCEPTION_POINTERS* exceptionInfo);
 #endif
 void os::init_system_properties_values() {
@@ -260,7 +263,8 @@
   }
 
 #ifndef _WIN64
-  SetUnhandledExceptionFilter(Handle_FLT_Exception);
+  // set our UnhandledExceptionFilter and save any previous one
+  prev_uef_handler = SetUnhandledExceptionFilter(Handle_FLT_Exception);
 #endif
 
   // Done
@@ -1969,7 +1973,7 @@
 #ifndef  _WIN64
 //-----------------------------------------------------------------------------
 LONG WINAPI Handle_FLT_Exception(struct _EXCEPTION_POINTERS* exceptionInfo) {
-  // handle exception caused by native mothod modifying control word
+  // handle exception caused by native method modifying control word
   PCONTEXT ctx = exceptionInfo->ContextRecord;
   DWORD exception_code = exceptionInfo->ExceptionRecord->ExceptionCode;
 
@@ -1990,6 +1994,13 @@
         return EXCEPTION_CONTINUE_EXECUTION;
       }
   }
+
+  if (prev_uef_handler != NULL) {
+    // We didn't handle this exception so pass it to the previous
+    // UnhandledExceptionFilter.
+    return (prev_uef_handler)(exceptionInfo);
+  }
+
   return EXCEPTION_CONTINUE_SEARCH;
 }
 #else //_WIN64
diff -r c09ee209b65c -r 7b4415a18c8a src/share/vm/c1/c1_LIRGenerator.cpp
--- a/src/share/vm/c1/c1_LIRGenerator.cpp	Fri Feb 12 10:34:11 2010 -0800
+++ b/src/share/vm/c1/c1_LIRGenerator.cpp	Fri Feb 12 15:27:36 2010 -0800
@@ -1,5 +1,5 @@
 /*
- * Copyright 2005-2009 Sun Microsystems, Inc.  All Rights Reserved.
+ * Copyright 2005-2010 Sun Microsystems, Inc.  All Rights Reserved.
  * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
  *
  * This code is free software; you can redistribute it and/or modify it
@@ -1765,7 +1765,7 @@
     __ null_check(exception_opr, new CodeEmitInfo(info, true));
   }
 
-  if (compilation()->env()->jvmti_can_post_exceptions() &&
+  if (compilation()->env()->jvmti_can_post_on_exceptions() &&
       !block()->is_set(BlockBegin::default_exception_handler_flag)) {
     // we need to go through the exception lookup path to get JVMTI
     // notification done
diff -r c09ee209b65c -r 7b4415a18c8a src/share/vm/c1/c1_Runtime1.cpp
--- a/src/share/vm/c1/c1_Runtime1.cpp	Fri Feb 12 10:34:11 2010 -0800
+++ b/src/share/vm/c1/c1_Runtime1.cpp	Fri Feb 12 15:27:36 2010 -0800
@@ -1,5 +1,5 @@
 /*
- * Copyright 1999-2009 Sun Microsystems, Inc.  All Rights Reserved.
+ * Copyright 1999-2010 Sun Microsystems, Inc.  All Rights Reserved.
  * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
  *
  * This code is free software; you can redistribute it and/or modify it
@@ -110,8 +110,8 @@
     RegisterMap reg_map(thread, false);
     frame runtime_frame = thread->last_frame();
     frame caller_frame = runtime_frame.sender(&reg_map);
-    VM_DeoptimizeFrame deopt(thread, caller_frame.id());
-    VMThread::execute(&deopt);
+    // bypass VM_DeoptimizeFrame and deoptimize the frame directly
+    Deoptimization::deoptimize_frame(thread, caller_frame.id());
     assert(caller_is_deopted(), "Must be deoptimized");
   }
 }
@@ -354,7 +354,7 @@
 
 
 JRT_ENTRY(void, Runtime1::post_jvmti_exception_throw(JavaThread* thread))
-  if (JvmtiExport::can_post_exceptions()) {
+  if (JvmtiExport::can_post_on_exceptions()) {
     vframeStream vfst(thread, true);
     address bcp = vfst.method()->bcp_from(vfst.bci());
     JvmtiExport::post_exception_throw(thread, vfst.method(), bcp, thread->exception_oop());
@@ -437,7 +437,7 @@
   bool guard_pages_enabled = thread->stack_yellow_zone_enabled();
   if (!guard_pages_enabled) guard_pages_enabled = thread->reguard_stack();
 
-  if (JvmtiExport::can_post_exceptions()) {
+  if (JvmtiExport::can_post_on_exceptions()) {
     // To ensure correct notification of exception catches and throws
     // we have to deoptimize here.  If we attempted to notify the
     // catches and throws during this exception lookup it's possible
@@ -1075,6 +1075,7 @@
 };
 
 
+// Below length is the # elements copied.
 template <class T> int obj_arraycopy_work(oopDesc* src, T* src_addr,
                                           oopDesc* dst, T* dst_addr,
                                           int length) {
@@ -1083,22 +1084,22 @@
   // barrier. The assert will fail if this is not the case.
   // Note that we use the non-virtual inlineable variant of write_ref_array.
   BarrierSet* bs = Universe::heap()->barrier_set();
-  assert(bs->has_write_ref_array_opt(),
-         "Barrier set must have ref array opt");
+  assert(bs->has_write_ref_array_opt(), "Barrier set must have ref array opt");
+  assert(bs->has_write_ref_array_pre_opt(), "For pre-barrier as well.");
   if (src == dst) {
     // same object, no check
+    bs->write_ref_array_pre(dst_addr, length);
     Copy::conjoint_oops_atomic(src_addr, dst_addr, length);
-    bs->write_ref_array(MemRegion((HeapWord*)dst_addr,
-                                  (HeapWord*)(dst_addr + length)));
+    bs->write_ref_array((HeapWord*)dst_addr, length);
     return ac_ok;
   } else {
     klassOop bound = objArrayKlass::cast(dst->klass())->element_klass();
     klassOop stype = objArrayKlass::cast(src->klass())->element_klass();
     if (stype == bound || Klass::cast(stype)->is_subtype_of(bound)) {
       // Elements are guaranteed to be subtypes, so no check necessary
+      bs->write_ref_array_pre(dst_addr, length);
       Copy::conjoint_oops_atomic(src_addr, dst_addr, length);
-      bs->write_ref_array(MemRegion((HeapWord*)dst_addr,
-                                    (HeapWord*)(dst_addr + length)));
+      bs->write_ref_array((HeapWord*)dst_addr, length);
       return ac_ok;
     }
   }
@@ -1162,9 +1163,16 @@
 #endif
 
   if (num == 0) return;
+  BarrierSet* bs = Universe::heap()->barrier_set();
+  assert(bs->has_write_ref_array_opt(), "Barrier set must have ref array opt");
+  assert(bs->has_write_ref_array_pre_opt(), "For pre-barrier as well.");
+  if (UseCompressedOops) {
+    bs->write_ref_array_pre((narrowOop*)dst, num);
+  } else {
+    bs->write_ref_array_pre((oop*)dst, num);
+  }
   Copy::conjoint_oops_atomic((oop*) src, (oop*) dst, num);
-  BarrierSet* bs = Universe::heap()->barrier_set();
-  bs->write_ref_array(MemRegion(dst, dst + num));
+  bs->write_ref_array(dst, num);
 JRT_END
 
 
diff -r c09ee209b65c -r 7b4415a18c8a src/share/vm/ci/ciEnv.cpp
--- a/src/share/vm/ci/ciEnv.cpp	Fri Feb 12 10:34:11 2010 -0800
+++ b/src/share/vm/ci/ciEnv.cpp	Fri Feb 12 15:27:36 2010 -0800
@@ -1,5 +1,5 @@
 /*
- * Copyright 1999-2009 Sun Microsystems, Inc.  All Rights Reserved.
+ * Copyright 1999-2010 Sun Microsystems, Inc.  All Rights Reserved.
  * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
  *
  * This code is free software; you can redistribute it and/or modify it
@@ -178,7 +178,7 @@
   _jvmti_can_hotswap_or_post_breakpoint = JvmtiExport::can_hotswap_or_post_breakpoint();
   _jvmti_can_examine_or_deopt_anywhere  = JvmtiExport::can_examine_or_deopt_anywhere();
   _jvmti_can_access_local_variables     = JvmtiExport::can_access_local_variables();
-  _jvmti_can_post_exceptions            = JvmtiExport::can_post_exceptions();
+  _jvmti_can_post_on_exceptions         = JvmtiExport::can_post_on_exceptions();
 }
 
 // ------------------------------------------------------------------
@@ -891,8 +891,8 @@
            JvmtiExport::can_examine_or_deopt_anywhere()) ||
           (!jvmti_can_access_local_variables() &&
            JvmtiExport::can_access_local_variables()) ||
-          (!jvmti_can_post_exceptions() &&
-           JvmtiExport::can_post_exceptions()) )) {
+          (!jvmti_can_post_on_exceptions() &&
+           JvmtiExport::can_post_on_exceptions()) )) {
       record_failure("Jvmti state change invalidated dependencies");
     }
 
diff -r c09ee209b65c -r 7b4415a18c8a src/share/vm/ci/ciEnv.hpp
--- a/src/share/vm/ci/ciEnv.hpp	Fri Feb 12 10:34:11 2010 -0800
+++ b/src/share/vm/ci/ciEnv.hpp	Fri Feb 12 15:27:36 2010 -0800
@@ -1,5 +1,5 @@
 /*
- * Copyright 1999-2009 Sun Microsystems, Inc.  All Rights Reserved.
+ * Copyright 1999-2010 Sun Microsystems, Inc.  All Rights Reserved.
  * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
  *
  * This code is free software; you can redistribute it and/or modify it
@@ -57,7 +57,7 @@
   bool  _jvmti_can_hotswap_or_post_breakpoint;
   bool  _jvmti_can_examine_or_deopt_anywhere;
   bool  _jvmti_can_access_local_variables;
-  bool  _jvmti_can_post_exceptions;
+  bool  _jvmti_can_post_on_exceptions;
 
   // Cache DTrace flags
   bool  _dtrace_extended_probes;
@@ -259,7 +259,7 @@
   bool  jvmti_can_hotswap_or_post_breakpoint() const { return _jvmti_can_hotswap_or_post_breakpoint; }
   bool  jvmti_can_examine_or_deopt_anywhere()  const { return _jvmti_can_examine_or_deopt_anywhere; }
   bool  jvmti_can_access_local_variables()     const { return _jvmti_can_access_local_variables; }
-  bool  jvmti_can_post_exceptions()            const { return _jvmti_can_post_exceptions; }
+  bool  jvmti_can_post_on_exceptions()         const { return _jvmti_can_post_on_exceptions; }
 
   // Cache DTrace flags
   void  cache_dtrace_flags();
diff -r c09ee209b65c -r 7b4415a18c8a src/share/vm/classfile/javaClasses.cpp
--- a/src/share/vm/classfile/javaClasses.cpp	Fri Feb 12 10:34:11 2010 -0800
+++ b/src/share/vm/classfile/javaClasses.cpp	Fri Feb 12 15:27:36 2010 -0800
@@ -1121,10 +1121,23 @@
   }
 
   void flush() {
+    // The following appears to have been an optimization to save from
+    // doing a barrier for each individual store into the _methods array,
+    // but rather to do it for the entire array after the series of writes.
+    // That optimization seems to have been lost when compressed oops was
+    // implemented. However, the extra card-marks below was left in place,
+    // but is now redundant because the individual stores into the
+    // _methods array already execute the barrier code. CR 6918185 has
+    // been filed so the original code may be restored by deferring the
+    // barriers until after the entire sequence of stores, thus re-enabling
+    // the intent of the original optimization. In the meantime the redundant
+    // card mark below is now disabled.
     if (_dirty && _methods != NULL) {
+#if 0
       BarrierSet* bs = Universe::heap()->barrier_set();
       assert(bs->has_write_ref_array_opt(), "Barrier set must have ref array opt");
       bs->write_ref_array((HeapWord*)_methods->base(), _methods->length());
+#endif
       _dirty = false;
     }
   }
@@ -1168,9 +1181,7 @@
       method = mhandle();
     }
 
-     _methods->obj_at_put(_index, method);
-    // bad for UseCompressedOops
-    // *_methods->obj_at_addr(_index) = method;
+    _methods->obj_at_put(_index, method);
     _bcis->ushort_at_put(_index, bci);
     _index++;
     _dirty = true;
diff -r c09ee209b65c -r 7b4415a18c8a src/share/vm/gc_implementation/g1/concurrentG1Refine.cpp
--- a/src/share/vm/gc_implementation/g1/concurrentG1Refine.cpp	Fri Feb 12 10:34:11 2010 -0800
+++ b/src/share/vm/gc_implementation/g1/concurrentG1Refine.cpp	Fri Feb 12 15:27:36 2010 -0800
@@ -300,7 +300,23 @@
   int count;
   jbyte* cached_ptr = add_card_count(card_ptr, &count, defer);
   assert(cached_ptr != NULL, "bad cached card ptr");
-  assert(!is_young_card(cached_ptr), "shouldn't get a card in young region");
+
+  if (is_young_card(cached_ptr)) {
+    // The region containing cached_ptr has been freed during a clean up
+    // pause, reallocated, and tagged as young.
+    assert(cached_ptr != card_ptr, "shouldn't be");
+
+    // We've just inserted a new old-gen card pointer into the card count
+    // cache and evicted the previous contents of that count slot.
+    // The evicted card pointer has been determined to be in a young region
+    // and so cannot be the newly inserted card pointer (that will be
+    // in an old region).
+    // The count for newly inserted card will be set to zero during the
+    // insertion, so we don't want to defer the cleaning of the newly
+    // inserted card pointer.
+    assert(*defer == false, "deferring non-hot card");
+    return NULL;
+  }
 
   // The card pointer we obtained from card count cache is not hot
   // so do not store it in the cache; return it for immediate
diff -r c09ee209b65c -r 7b4415a18c8a src/share/vm/gc_implementation/g1/g1CollectedHeap.cpp
--- a/src/share/vm/gc_implementation/g1/g1CollectedHeap.cpp	Fri Feb 12 10:34:11 2010 -0800
+++ b/src/share/vm/gc_implementation/g1/g1CollectedHeap.cpp	Fri Feb 12 15:27:36 2010 -0800
@@ -2505,6 +2505,7 @@
 }
 
 void G1CollectedHeap::gc_prologue(bool full /* Ignored */) {
+  // always_do_update_barrier = false;
   assert(InlineCacheBuffer::is_empty(), "should have cleaned up ICBuffer");
   // Call allocation profiler
   AllocationProfiler::iterate_since_last_gc();
@@ -2518,6 +2519,7 @@
   // is set.
   COMPILER2_PRESENT(assert(DerivedPointerTable::is_empty(),
                         "derived pointer present"));
+  // always_do_update_barrier = true;
 }
 
 void G1CollectedHeap::do_collection_pause() {
diff -r c09ee209b65c -r 7b4415a18c8a src/share/vm/includeDB_core
--- a/src/share/vm/includeDB_core	Fri Feb 12 10:34:11 2010 -0800
+++ b/src/share/vm/includeDB_core	Fri Feb 12 15:27:36 2010 -0800
@@ -175,6 +175,7 @@
 arguments.cpp                           management.hpp
 arguments.cpp                           oop.inline.hpp
 arguments.cpp                           os_<os_family>.inline.hpp
+arguments.cpp                           referenceProcessor.hpp
 arguments.cpp                           universe.inline.hpp
 arguments.cpp                           vm_version_<arch>.hpp
 
diff -r c09ee209b65c -r 7b4415a18c8a src/share/vm/interpreter/interpreterRuntime.cpp
--- a/src/share/vm/interpreter/interpreterRuntime.cpp	Fri Feb 12 10:34:11 2010 -0800
+++ b/src/share/vm/interpreter/interpreterRuntime.cpp	Fri Feb 12 15:27:36 2010 -0800
@@ -1,5 +1,5 @@
 /*
- * Copyright 1997-2009 Sun Microsystems, Inc.  All Rights Reserved.
+ * Copyright 1997-2010 Sun Microsystems, Inc.  All Rights Reserved.
  * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
  *
  * This code is free software; you can redistribute it and/or modify it
@@ -397,7 +397,7 @@
 
   // notify JVMTI of an exception throw; JVMTI will detect if this is a first
   // time throw or a stack unwinding throw and accordingly notify the debugger
-  if (JvmtiExport::can_post_exceptions()) {
+  if (JvmtiExport::can_post_on_exceptions()) {
     JvmtiExport::post_exception_throw(thread, h_method(), bcp(thread), h_exception());
   }
 
@@ -426,7 +426,7 @@
   }
   // notify debugger of an exception catch
   // (this is good for exceptions caught in native methods as well)
-  if (JvmtiExport::can_post_exceptions()) {
+  if (JvmtiExport::can_post_on_exceptions()) {
     JvmtiExport::notice_unwind_due_to_exception(thread, h_method(), handler_pc, h_exception(), (handler_pc != NULL));
   }
 
diff -r c09ee209b65c -r 7b4415a18c8a src/share/vm/memory/barrierSet.hpp
--- a/src/share/vm/memory/barrierSet.hpp	Fri Feb 12 10:34:11 2010 -0800
+++ b/src/share/vm/memory/barrierSet.hpp	Fri Feb 12 15:27:36 2010 -0800
@@ -124,8 +124,6 @@
   // Below length is the # array elements being written
   virtual void write_ref_array_pre(      oop* dst, int length) {}
   virtual void write_ref_array_pre(narrowOop* dst, int length) {}
-  // Below MemRegion mr is expected to be HeapWord-aligned
-  inline void write_ref_array(MemRegion mr);
   // Below count is the # array elements being written, starting
   // at the address "start", which may not necessarily be HeapWord-aligned
   inline void write_ref_array(HeapWord* start, size_t count);
diff -r c09ee209b65c -r 7b4415a18c8a src/share/vm/memory/barrierSet.inline.hpp
--- a/src/share/vm/memory/barrierSet.inline.hpp	Fri Feb 12 10:34:11 2010 -0800
+++ b/src/share/vm/memory/barrierSet.inline.hpp	Fri Feb 12 15:27:36 2010 -0800
@@ -42,16 +42,6 @@
   }
 }
 
-void BarrierSet::write_ref_array(MemRegion mr) {
-  assert((HeapWord*)align_size_down((uintptr_t)mr.start(), HeapWordSize) == mr.start() , "Unaligned start");
-  assert((HeapWord*)align_size_up  ((uintptr_t)mr.end(),   HeapWordSize) == mr.end(),    "Unaligned end"  );
-  if (kind() == CardTableModRef) {
-    ((CardTableModRefBS*)this)->inline_write_ref_array(mr);
-  } else {
-    write_ref_array_work(mr);
-  }
-}
-
 // count is number of array elements being written
 void BarrierSet::write_ref_array(HeapWord* start, size_t count) {
   assert(count <= (size_t)max_intx, "count too large");
@@ -61,12 +51,12 @@
   // strictly necessary for current uses, but a case of good hygiene and,
   // if you will, aesthetics) and the second upward (this is essential for
   // current uses) to a HeapWord boundary, so we mark all cards overlapping
-  // this write. In the event that this evolves in the future to calling a
+  // this write. If this evolves in the future to calling a
   // logging barrier of narrow oop granularity, like the pre-barrier for G1
   // (mentioned here merely by way of example), we will need to change this
-  // interface, much like the pre-barrier one above, so it is "exactly precise"
-  // (if i may be allowed the adverbial redundancy for emphasis) and does not
-  // include narrow oop slots not included in the original write interval.
+  // interface, so it is "exactly precise" (if i may be allowed the adverbial
+  // redundancy for emphasis) and does not include narrow oop slots not
+  // included in the original write interval.
   HeapWord* aligned_start = (HeapWord*)align_size_down((uintptr_t)start, HeapWordSize);
   HeapWord* aligned_end   = (HeapWord*)align_size_up  ((uintptr_t)end,   HeapWordSize);
   // If compressed oops were not being used, these should already be aligned
diff -r c09ee209b65c -r 7b4415a18c8a src/share/vm/memory/referenceProcessor.hpp
--- a/src/share/vm/memory/referenceProcessor.hpp	Fri Feb 12 10:34:11 2010 -0800
+++ b/src/share/vm/memory/referenceProcessor.hpp	Fri Feb 12 15:27:36 2010 -0800
@@ -263,10 +263,13 @@
     int                parallel_gc_threads = 1,
     bool               mt_processing = false,
     bool               discovered_list_needs_barrier = false);
+
   // RefDiscoveryPolicy values
-  enum {
+  enum DiscoveryPolicy {
     ReferenceBasedDiscovery = 0,
-    ReferentBasedDiscovery  = 1
+    ReferentBasedDiscovery  = 1,
+    DiscoveryPolicyMin      = ReferenceBasedDiscovery,
+    DiscoveryPolicyMax      = ReferentBasedDiscovery
   };
 
   static void init_statics();
diff -r c09ee209b65c -r 7b4415a18c8a src/share/vm/opto/graphKit.cpp
--- a/src/share/vm/opto/graphKit.cpp	Fri Feb 12 10:34:11 2010 -0800
+++ b/src/share/vm/opto/graphKit.cpp	Fri Feb 12 15:27:36 2010 -0800
@@ -455,16 +455,44 @@
     return Bytecodes::_illegal;
 }
 
+void GraphKit::uncommon_trap_if_should_post_on_exceptions(Deoptimization::DeoptReason reason,
+                                                          bool must_throw) {
+    // if the exception capability is set, then we will generate code
+    // to check the JavaThread.should_post_on_exceptions flag to see
+    // if we actually need to report exception events (for this
+    // thread).  If we don't need to report exception events, we will
+    // take the normal fast path provided by add_exception_events.  If
+    // exception event reporting is enabled for this thread, we will
+    // take the uncommon_trap in the BuildCutout below.
+
+    // first must access the should_post_on_exceptions_flag in this thread's JavaThread
+    Node* jthread = _gvn.transform(new (C, 1) ThreadLocalNode());
+    Node* adr = basic_plus_adr(top(), jthread, in_bytes(JavaThread::should_post_on_exceptions_flag_offset()));
+    Node* should_post_flag = make_load(control(), adr, TypeInt::INT, T_INT, Compile::AliasIdxRaw, false);
+
+    // Test the should_post_on_exceptions_flag vs. 0
+    Node* chk = _gvn.transform( new (C, 3) CmpINode(should_post_flag, intcon(0)) );
+    Node* tst = _gvn.transform( new (C, 2) BoolNode(chk, BoolTest::eq) );
+
+    // Branch to slow_path if should_post_on_exceptions_flag was true
+    { BuildCutout unless(this, tst, PROB_MAX);
+      // Do not try anything fancy if we're notifying the VM on every throw.
+      // Cf. case Bytecodes::_athrow in parse2.cpp.
+      uncommon_trap(reason, Deoptimization::Action_none,
+                    (ciKlass*)NULL, (char*)NULL, must_throw);
+    }
+
+}
+
 //------------------------------builtin_throw----------------------------------
 void GraphKit::builtin_throw(Deoptimization::DeoptReason reason, Node* arg) {
   bool must_throw = true;
 
-  if (env()->jvmti_can_post_exceptions()) {
-    // Do not try anything fancy if we're notifying the VM on every throw.
-    // Cf. case Bytecodes::_athrow in parse2.cpp.
-    uncommon_trap(reason, Deoptimization::Action_none,
-                  (ciKlass*)NULL, (char*)NULL, must_throw);
-    return;
+  if (env()->jvmti_can_post_on_exceptions()) {
+    // check if we must post exception events, take uncommon trap if so
+    uncommon_trap_if_should_post_on_exceptions(reason, must_throw);
+    // here if should_post_on_exceptions is false
+    // continue on with the normal codegen
   }
 
   // If this particular condition has not yet happened at this
diff -r c09ee209b65c -r 7b4415a18c8a src/share/vm/opto/graphKit.hpp
--- a/src/share/vm/opto/graphKit.hpp	Fri Feb 12 10:34:11 2010 -0800
+++ b/src/share/vm/opto/graphKit.hpp	Fri Feb 12 15:27:36 2010 -0800
@@ -1,5 +1,5 @@
 /*
- * Copyright 2001-2009 Sun Microsystems, Inc.  All Rights Reserved.
+ * Copyright 2001-2010 Sun Microsystems, Inc.  All Rights Reserved.
  * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
  *
  * This code is free software; you can redistribute it and/or modify it
@@ -251,6 +251,11 @@
   // via an uncommon trap.
   void builtin_throw(Deoptimization::DeoptReason reason, Node* arg = NULL);
 
+  // Helper to check the JavaThread::_should_post_on_exceptions flag
+  // and branch to an uncommon_trap if it is true (with the specified reason and must_throw)
+  void uncommon_trap_if_should_post_on_exceptions(Deoptimization::DeoptReason reason,
+                                                  bool must_throw) ;
+
   // Helper Functions for adding debug information
   void kill_dead_locals();
 #ifdef ASSERT
diff -r c09ee209b65c -r 7b4415a18c8a src/share/vm/opto/parse2.cpp
--- a/src/share/vm/opto/parse2.cpp	Fri Feb 12 10:34:11 2010 -0800
+++ b/src/share/vm/opto/parse2.cpp	Fri Feb 12 15:27:36 2010 -0800
@@ -1,5 +1,5 @@
 /*
- * Copyright 1998-2009 Sun Microsystems, Inc.  All Rights Reserved.
+ * Copyright 1998-2010 Sun Microsystems, Inc.  All Rights Reserved.
  * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
  *
  * This code is free software; you can redistribute it and/or modify it
@@ -2079,13 +2079,6 @@
     // null exception oop throws NULL pointer exception
     do_null_check(peek(), T_OBJECT);
     if (stopped())  return;
-    if (env()->jvmti_can_post_exceptions()) {
-      // "Full-speed throwing" is not necessary here,
-      // since we're notifying the VM on every throw.
-      uncommon_trap(Deoptimization::Reason_unhandled,
-                    Deoptimization::Action_none);
-      return;
-    }
     // Hook the thrown exception directly to subsequent handlers.
     if (BailoutToInterpreterForThrows) {
       // Keep method interpreted from now on.
@@ -2093,6 +2086,11 @@
                     Deoptimization::Action_make_not_compilable);
       return;
     }
+    if (env()->jvmti_can_post_on_exceptions()) {
+      // check if we must post exception events, take uncommon trap if so (with must_throw = false)
+      uncommon_trap_if_should_post_on_exceptions(Deoptimization::Reason_unhandled, false);
+    }
+    // Here if either can_post_on_exceptions or should_post_on_exceptions is false
     add_exception_state(make_exception_state(peek()));
     break;
 
diff -r c09ee209b65c -r 7b4415a18c8a src/share/vm/opto/runtime.cpp
--- a/src/share/vm/opto/runtime.cpp	Fri Feb 12 10:34:11 2010 -0800
+++ b/src/share/vm/opto/runtime.cpp	Fri Feb 12 15:27:36 2010 -0800
@@ -815,7 +815,7 @@
     // we are switching to old paradigm: search for exception handler in caller_frame
     // instead in exception handler of caller_frame.sender()
 
-    if (JvmtiExport::can_post_exceptions()) {
+    if (JvmtiExport::can_post_on_exceptions()) {
       // "Full-speed catching" is not necessary here,
       // since we're notifying the VM on every catch.
       // Force deoptimization and the rest of the lookup
@@ -980,8 +980,8 @@
     assert(stub_frame.is_runtime_frame() || exception_blob()->contains(stub_frame.pc()), "sanity check");
     frame caller_frame = stub_frame.sender(&reg_map);
 
-    VM_DeoptimizeFrame deopt(thread, caller_frame.id());
-    VMThread::execute(&deopt);
+    // bypass VM_DeoptimizeFrame and deoptimize the frame directly
+    Deoptimization::deoptimize_frame(thread, caller_frame.id());
   }
 }
 
diff -r c09ee209b65c -r 7b4415a18c8a src/share/vm/prims/jvmtiEventController.cpp
--- a/src/share/vm/prims/jvmtiEventController.cpp	Fri Feb 12 10:34:11 2010 -0800
+++ b/src/share/vm/prims/jvmtiEventController.cpp	Fri Feb 12 15:27:36 2010 -0800
@@ -1,5 +1,5 @@
 /*
- * Copyright 2003-2007 Sun Microsystems, Inc.  All Rights Reserved.
+ * Copyright 2003-2010 Sun Microsystems, Inc.  All Rights Reserved.
  * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
  *
  * This code is free software; you can redistribute it and/or modify it
@@ -82,7 +82,7 @@
                                THREAD_START_BIT | THREAD_END_BIT |
                                DYNAMIC_CODE_GENERATED_BIT;
 static const jlong  GLOBAL_EVENT_BITS = ~THREAD_FILTERED_EVENT_BITS;
-
+static const jlong  SHOULD_POST_ON_EXCEPTIONS_BITS = EXCEPTION_BITS | METHOD_EXIT_BIT | FRAME_POP_BIT;
 
 ///////////////////////////////////////////////////////////////
 //
@@ -511,7 +511,12 @@
         leave_interp_only_mode(state);
       }
     }
+
+    // update the JavaThread cached value for thread-specific should_post_on_exceptions value
+    bool should_post_on_exceptions = (any_env_enabled & SHOULD_POST_ON_EXCEPTIONS_BITS) != 0;
+    state->set_should_post_on_exceptions(should_post_on_exceptions);
   }
+
   return any_env_enabled;
 }
 
@@ -615,6 +620,10 @@
 
     // set global truly enabled, that is, any thread in any environment
     JvmtiEventController::_universal_global_event_enabled.set_bits(any_env_thread_enabled);
+
+    // set global should_post_on_exceptions
+    JvmtiExport::set_should_post_on_exceptions((any_env_thread_enabled & SHOULD_POST_ON_EXCEPTIONS_BITS) != 0);
+
   }
 
   EC_TRACE(("JVMTI [-] # recompute enabled - after %llx", any_env_thread_enabled));
diff -r c09ee209b65c -r 7b4415a18c8a src/share/vm/prims/jvmtiExport.cpp
--- a/src/share/vm/prims/jvmtiExport.cpp	Fri Feb 12 10:34:11 2010 -0800
+++ b/src/share/vm/prims/jvmtiExport.cpp	Fri Feb 12 15:27:36 2010 -0800
@@ -877,7 +877,7 @@
 bool              JvmtiExport::_can_get_source_debug_extension            = false;
 bool              JvmtiExport::_can_maintain_original_method_order        = false;
 bool              JvmtiExport::_can_post_interpreter_events               = false;
-bool              JvmtiExport::_can_post_exceptions                       = false;
+bool              JvmtiExport::_can_post_on_exceptions                    = false;
 bool              JvmtiExport::_can_post_breakpoint                       = false;
 bool              JvmtiExport::_can_post_field_access                     = false;
 bool              JvmtiExport::_can_post_field_modification               = false;
@@ -908,6 +908,7 @@
 bool              JvmtiExport::_should_post_object_free                   = false;
 bool              JvmtiExport::_should_post_resource_exhausted            = false;
 bool              JvmtiExport::_should_post_vm_object_alloc               = false;
+bool              JvmtiExport::_should_post_on_exceptions                 = false;
 
 ////////////////////////////////////////////////////////////////////////////////////////////////
 
diff -r c09ee209b65c -r 7b4415a18c8a src/share/vm/prims/jvmtiExport.hpp
--- a/src/share/vm/prims/jvmtiExport.hpp	Fri Feb 12 10:34:11 2010 -0800
+++ b/src/share/vm/prims/jvmtiExport.hpp	Fri Feb 12 15:27:36 2010 -0800
@@ -1,5 +1,5 @@
 /*
- * Copyright 1998-2009 Sun Microsystems, Inc.  All Rights Reserved.
+ * Copyright 1998-2010 Sun Microsystems, Inc.  All Rights Reserved.
  * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
  *
  * This code is free software; you can redistribute it and/or modify it
@@ -66,7 +66,7 @@
   JVMTI_SUPPORT_FLAG(can_get_source_debug_extension)
   JVMTI_SUPPORT_FLAG(can_maintain_original_method_order)
   JVMTI_SUPPORT_FLAG(can_post_interpreter_events)
-  JVMTI_SUPPORT_FLAG(can_post_exceptions)
+  JVMTI_SUPPORT_FLAG(can_post_on_exceptions)
   JVMTI_SUPPORT_FLAG(can_post_breakpoint)
   JVMTI_SUPPORT_FLAG(can_post_field_access)
   JVMTI_SUPPORT_FLAG(can_post_field_modification)
@@ -93,6 +93,7 @@
   JVMTI_SUPPORT_FLAG(should_post_data_dump)
   JVMTI_SUPPORT_FLAG(should_post_garbage_collection_start)
   JVMTI_SUPPORT_FLAG(should_post_garbage_collection_finish)
+  JVMTI_SUPPORT_FLAG(should_post_on_exceptions)
 
   // ------ the below maybe don't have to be (but are for now)
   // fixed conditions here ------------
diff -r c09ee209b65c -r 7b4415a18c8a src/share/vm/prims/jvmtiManageCapabilities.cpp
--- a/src/share/vm/prims/jvmtiManageCapabilities.cpp	Fri Feb 12 10:34:11 2010 -0800
+++ b/src/share/vm/prims/jvmtiManageCapabilities.cpp	Fri Feb 12 15:27:36 2010 -0800
@@ -1,5 +1,5 @@
 /*
- * Copyright 2003-2006 Sun Microsystems, Inc.  All Rights Reserved.
+ * Copyright 2003-2010 Sun Microsystems, Inc.  All Rights Reserved.
  * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
  *
  * This code is free software; you can redistribute it and/or modify it
@@ -357,7 +357,7 @@
     avail.can_access_local_variables  ||
     avail.can_redefine_classes ||
     avail.can_retransform_classes);
-  JvmtiExport::set_can_post_exceptions(
+  JvmtiExport::set_can_post_on_exceptions(
     avail.can_generate_exception_events ||
     avail.can_generate_frame_pop_events ||
     avail.can_generate_method_exit_events);
diff -r c09ee209b65c -r 7b4415a18c8a src/share/vm/prims/jvmtiThreadState.hpp
--- a/src/share/vm/prims/jvmtiThreadState.hpp	Fri Feb 12 10:34:11 2010 -0800
+++ b/src/share/vm/prims/jvmtiThreadState.hpp	Fri Feb 12 15:27:36 2010 -0800
@@ -1,5 +1,5 @@
 /*
- * Copyright 2003-2006 Sun Microsystems, Inc.  All Rights Reserved.
+ * Copyright 2003-2010 Sun Microsystems, Inc.  All Rights Reserved.
  * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
  *
  * This code is free software; you can redistribute it and/or modify it
@@ -381,6 +381,9 @@
   static ByteSize earlyret_value_offset() { return byte_offset_of(JvmtiThreadState, _earlyret_value); }
 
   void oops_do(OopClosure* f); // GC support
+
+public:
+  void set_should_post_on_exceptions(bool val) { _thread->set_should_post_on_exceptions_flag(val ? JNI_TRUE : JNI_FALSE); }
 };
 
 class RedefineVerifyMark : public StackObj {
diff -r c09ee209b65c -r 7b4415a18c8a src/share/vm/runtime/arguments.cpp
--- a/src/share/vm/runtime/arguments.cpp	Fri Feb 12 10:34:11 2010 -0800
+++ b/src/share/vm/runtime/arguments.cpp	Fri Feb 12 15:27:36 2010 -0800
@@ -1487,6 +1487,20 @@
 //===========================================================================================================
 // Parsing of main arguments
 
+bool Arguments::verify_interval(uintx val, uintx min,
+                                uintx max, const char* name) {
+  // Returns true iff value is in the inclusive interval [min..max]
+  // false, otherwise.
+  if (val >= min && val <= max) {
+    return true;
+  }
+  jio_fprintf(defaultStream::error_stream(),
+              "%s of " UINTX_FORMAT " is invalid; must be between " UINTX_FORMAT
+              " and " UINTX_FORMAT "\n",
+              name, val, min, max);
+  return false;
+}
+
 bool Arguments::verify_percentage(uintx value, const char* name) {
   if (value <= 100) {
     return true;
@@ -1723,6 +1737,16 @@
     status = false;
   }
 
+  status = status && verify_interval(RefDiscoveryPolicy,
+                                     ReferenceProcessor::DiscoveryPolicyMin,
+                                     ReferenceProcessor::DiscoveryPolicyMax,
+                                     "RefDiscoveryPolicy");
+
+  // Limit the lower bound of this flag to 1 as it is used in a division
+  // expression.
+  status = status && verify_interval(TLABWasteTargetPercent,
+                                     1, 100, "TLABWasteTargetPercent");
+
   return status;
 }
 
diff -r c09ee209b65c -r 7b4415a18c8a src/share/vm/runtime/arguments.hpp
--- a/src/share/vm/runtime/arguments.hpp	Fri Feb 12 10:34:11 2010 -0800
+++ b/src/share/vm/runtime/arguments.hpp	Fri Feb 12 15:27:36 2010 -0800
@@ -336,6 +336,8 @@
   static bool is_bad_option(const JavaVMOption* option, jboolean ignore) {
     return is_bad_option(option, ignore, NULL);
   }
+  static bool verify_interval(uintx val, uintx min,
+                              uintx max, const char* name);
   static bool verify_percentage(uintx value, const char* name);
   static void describe_range_error(ArgsRange errcode);
   static ArgsRange check_memory_size(julong size, julong min_size);
diff -r c09ee209b65c -r 7b4415a18c8a src/share/vm/runtime/sharedRuntime.cpp
--- a/src/share/vm/runtime/sharedRuntime.cpp	Fri Feb 12 10:34:11 2010 -0800
+++ b/src/share/vm/runtime/sharedRuntime.cpp	Fri Feb 12 15:27:36 2010 -0800
@@ -364,7 +364,7 @@
 
 
 void SharedRuntime::throw_and_post_jvmti_exception(JavaThread *thread, Handle h_exception) {
-  if (JvmtiExport::can_post_exceptions()) {
+  if (JvmtiExport::can_post_on_exceptions()) {
     vframeStream vfst(thread, true);
     methodHandle method = methodHandle(thread, vfst.method());
     address bcp = method()->bcp_from(vfst.bci());
diff -r c09ee209b65c -r 7b4415a18c8a src/share/vm/runtime/stubRoutines.cpp
--- a/src/share/vm/runtime/stubRoutines.cpp	Fri Feb 12 10:34:11 2010 -0800
+++ b/src/share/vm/runtime/stubRoutines.cpp	Fri Feb 12 15:27:36 2010 -0800
@@ -196,11 +196,19 @@
 // Default versions of arraycopy functions
 //
 
+static void gen_arraycopy_barrier_pre(oop* dest, size_t count) {
+    assert(count != 0, "count should be non-zero");
+    assert(count <= (size_t)max_intx, "count too large");
+    BarrierSet* bs = Universe::heap()->barrier_set();
+    assert(bs->has_write_ref_array_pre_opt(), "Must have pre-barrier opt");
+    bs->write_ref_array_pre(dest, (int)count);
+}
+
 static void gen_arraycopy_barrier(oop* dest, size_t count) {
     assert(count != 0, "count should be non-zero");
     BarrierSet* bs = Universe::heap()->barrier_set();
     assert(bs->has_write_ref_array_opt(), "Barrier set must have ref array opt");
-    bs->write_ref_array(MemRegion((HeapWord*)dest, (HeapWord*)(dest + count)));
+    bs->write_ref_array((HeapWord*)dest, count);
 }
 
 JRT_LEAF(void, StubRoutines::jbyte_copy(jbyte* src, jbyte* dest, size_t count))
@@ -240,6 +248,7 @@
   SharedRuntime::_oop_array_copy_ctr++;        // Slow-path oop array copy
 #endif // !PRODUCT
   assert(count != 0, "count should be non-zero");
+  gen_arraycopy_barrier_pre(dest, count);
   Copy::conjoint_oops_atomic(src, dest, count);
   gen_arraycopy_barrier(dest, count);
 JRT_END
@@ -281,6 +290,7 @@
   SharedRuntime::_oop_array_copy_ctr++;        // Slow-path oop array copy
 #endif // !PRODUCT
   assert(count != 0, "count should be non-zero");
+  gen_arraycopy_barrier_pre((oop *) dest, count);
   Copy::arrayof_conjoint_oops(src, dest, count);
   gen_arraycopy_barrier((oop *) dest, count);
 JRT_END
diff -r c09ee209b65c -r 7b4415a18c8a src/share/vm/runtime/thread.cpp
--- a/src/share/vm/runtime/thread.cpp	Fri Feb 12 10:34:11 2010 -0800
+++ b/src/share/vm/runtime/thread.cpp	Fri Feb 12 15:27:36 2010 -0800
@@ -1,5 +1,5 @@
 /*
- * Copyright 1997-2009 Sun Microsystems, Inc.  All Rights Reserved.
+ * Copyright 1997-2010 Sun Microsystems, Inc.  All Rights Reserved.
  * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
  *
  * This code is free software; you can redistribute it and/or modify it
@@ -1173,6 +1173,7 @@
   _exception_handler_pc = 0;
   _exception_stack_size = 0;
   _jvmti_thread_state= NULL;
+  _should_post_on_exceptions_flag = JNI_FALSE;
   _jvmti_get_loaded_classes_closure = NULL;
   _interp_only_mode    = 0;
   _special_runtime_exit_condition = _no_async_condition;
diff -r c09ee209b65c -r 7b4415a18c8a src/share/vm/runtime/thread.hpp
--- a/src/share/vm/runtime/thread.hpp	Fri Feb 12 10:34:11 2010 -0800
+++ b/src/share/vm/runtime/thread.hpp	Fri Feb 12 15:27:36 2010 -0800
@@ -1,5 +1,5 @@
 /*
- * Copyright 1997-2009 Sun Microsystems, Inc.  All Rights Reserved.
+ * Copyright 1997-2010 Sun Microsystems, Inc.  All Rights Reserved.
  * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
  *
  * This code is free software; you can redistribute it and/or modify it
@@ -1193,6 +1193,9 @@
   static ByteSize suspend_flags_offset()         { return byte_offset_of(JavaThread, _suspend_flags       ); }
 
   static ByteSize do_not_unlock_if_synchronized_offset() { return byte_offset_of(JavaThread, _do_not_unlock_if_synchronized); }
+  static ByteSize should_post_on_exceptions_flag_offset() {
+    return byte_offset_of(JavaThread, _should_post_on_exceptions_flag);
+  }
 
 #ifndef SERIALGC
   static ByteSize satb_mark_queue_offset()       { return byte_offset_of(JavaThread, _satb_mark_queue); }
@@ -1432,6 +1435,16 @@
   void increment_interp_only_mode()         { ++_interp_only_mode; }
   void decrement_interp_only_mode()         { --_interp_only_mode; }
 
+  // support for cached flag that indicates whether exceptions need to be posted for this thread
+  // if this is false, we can avoid deoptimizing when events are thrown
+  // this gets set to reflect whether jvmtiExport::post_exception_throw would actually do anything
+ private:
+  int    _should_post_on_exceptions_flag;
+
+ public:
+  int   should_post_on_exceptions_flag()  { return _should_post_on_exceptions_flag; }
+  void  set_should_post_on_exceptions_flag(int val)  { _should_post_on_exceptions_flag = val; }
+
  private:
   ThreadStatistics *_thread_stat;