# HG changeset patch
# User Tom Rodriguez <tom.rodriguez@oracle.com>
# Date 1446765690 28800
# Node ID eada427470a3aa671dd7f4fdce5197b60d1e4351
# Parent  2d21c13d7829a3457eeea3ba597e6b92b2fd0710
Use proper GC barriers when clearing _jvmci_installed_code

diff -r 2d21c13d7829 -r eada427470a3 src/share/vm/code/nmethod.cpp
--- a/src/share/vm/code/nmethod.cpp	Thu Nov 05 15:18:36 2015 -0800
+++ b/src/share/vm/code/nmethod.cpp	Thu Nov 05 15:21:30 2015 -0800
@@ -1978,9 +1978,7 @@
   if (_jvmci_installed_code != NULL) {
     if (_jvmci_installed_code->is_a(HotSpotNmethod::klass()) && HotSpotNmethod::isDefault(_jvmci_installed_code)) {
       if (!is_alive->do_object_b(_jvmci_installed_code)) {
-        bs->write_ref_nmethod_pre(&_jvmci_installed_code, this);
-        _jvmci_installed_code = NULL;
-        bs->write_ref_nmethod_post(&_jvmci_installed_code, this);
+        clear_jvmci_installed_code();
       }
     } else {
       if (can_unload(is_alive, (oop*)&_jvmci_installed_code, unloading_occurred)) {
@@ -2109,27 +2107,6 @@
     unloading_occurred = true;
   }
 
-#if INCLUDE_JVMCI
-  // Follow JVMCI method
-  if (_jvmci_installed_code != NULL) {
-    if (_jvmci_installed_code->is_a(HotSpotNmethod::klass()) && HotSpotNmethod::isDefault(_jvmci_installed_code)) {
-      if (!is_alive->do_object_b(_jvmci_installed_code)) {
-        _jvmci_installed_code = NULL;
-      }
-    } else {
-      if (can_unload(is_alive, (oop*)&_jvmci_installed_code, unloading_occurred)) {
-        return false;
-      }
-    }
-  }
-
-  if (_speculation_log != NULL) {
-    if (!is_alive->do_object_b(_speculation_log)) {
-      _speculation_log = NULL;
-    }
-  }
-#endif
-
   // When class redefinition is used all metadata in the CodeCache has to be recorded,
   // so that unused "previous versions" can be purged. Since walking the CodeCache can
   // be expensive, the "mark on stack" is piggy-backed on this parallel unloading code.
@@ -2204,9 +2181,7 @@
   if (_jvmci_installed_code != NULL) {
     if (_jvmci_installed_code->is_a(HotSpotNmethod::klass()) && HotSpotNmethod::isDefault(_jvmci_installed_code)) {
       if (!is_alive->do_object_b(_jvmci_installed_code)) {
-        bs->write_ref_nmethod_pre(&_jvmci_installed_code, this);
-        _jvmci_installed_code = NULL;
-        bs->write_ref_nmethod_post(&_jvmci_installed_code, this);
+        clear_jvmci_installed_code();
       }
     } else {
       if (can_unload(is_alive, (oop*)&_jvmci_installed_code, unloading_occurred)) {
@@ -3542,6 +3517,14 @@
 }
 
 #if INCLUDE_JVMCI
+void nmethod::clear_jvmci_installed_code() {
+  // This must be done carefully to maintain nmethod remembered sets properly
+  BarrierSet* bs = Universe::heap()->barrier_set();
+  bs->write_ref_nmethod_pre(&_jvmci_installed_code, this);
+  _jvmci_installed_code = NULL;
+  bs->write_ref_nmethod_post(&_jvmci_installed_code, this);
+}
+
 void nmethod::maybe_invalidate_installed_code() {
   if (_jvmci_installed_code != NULL) {
      if (!is_alive()) {
@@ -3551,7 +3534,7 @@
        // might want to invalidate all existing activations.
        InstalledCode::set_address(_jvmci_installed_code, 0);
        InstalledCode::set_entryPoint(_jvmci_installed_code, 0);
-       _jvmci_installed_code = NULL;
+       clear_jvmci_installed_code();
      } else if (is_not_entrant()) {
        InstalledCode::set_entryPoint(_jvmci_installed_code, 0);
      }
diff -r 2d21c13d7829 -r eada427470a3 src/share/vm/code/nmethod.hpp
--- a/src/share/vm/code/nmethod.hpp	Thu Nov 05 15:18:36 2015 -0800
+++ b/src/share/vm/code/nmethod.hpp	Thu Nov 05 15:21:30 2015 -0800
@@ -629,7 +629,7 @@
 #if INCLUDE_JVMCI
   oop jvmci_installed_code() { return _jvmci_installed_code ; }
   char* jvmci_installed_code_name(char* buf, size_t buflen);
-  void set_jvmci_installed_code(oop installed_code) { _jvmci_installed_code = installed_code;  }
+  void clear_jvmci_installed_code();
   void maybe_invalidate_installed_code();
   oop speculation_log() { return _speculation_log ; }
   void set_speculation_log(oop speculation_log) { _speculation_log = speculation_log;  }