8075805: Crash while trying to release CompiledICHolder

Summary: Removed nmethod transition to zombie outside of sweeper. Added cleaning of ICs of unloaded nmethods.
Reviewed-by: kvn, iveresov

src/share/vm/code/codeCache.cpp

@@ -524,12 +524,15 @@ void CodeCache::gc_epilogue() {
   FOR_ALL_ALIVE_BLOBS(cb) {
     if (cb->is_nmethod()) {
       nmethod *nm = (nmethod*)cb;
-      assert(!nm->is_unloaded(), "Tautology");
-      if (needs_cache_clean()) {
-        nm->cleanup_inline_caches();
+      if (!nm->is_zombie()) {
+        if (needs_cache_clean()) {
+          // Clean ICs of unloaded nmethods as well because they may reference other
+          // unloaded nmethods that may be flushed earlier in the sweeper cycle.
+          nm->cleanup_inline_caches();
+        }
+        DEBUG_ONLY(nm->verify());
+        DEBUG_ONLY(nm->verify_oop_relocations());
       }
-      DEBUG_ONLY(nm->verify());
-      DEBUG_ONLY(nm->verify_oop_relocations());
     }
   }
   set_needs_cache_clean(false);
@@ -734,27 +737,6 @@ int CodeCache::mark_for_deoptimization(Method* dependee) {
   return number_of_marked_CodeBlobs;
 }
 
-void CodeCache::make_marked_nmethods_zombies() {
-  assert(SafepointSynchronize::is_at_safepoint(), "must be at a safepoint");
-  FOR_ALL_ALIVE_NMETHODS(nm) {
-    if (nm->is_marked_for_deoptimization()) {
-
-      // If the nmethod has already been made non-entrant and it can be converted
-      // then zombie it now. Otherwise make it non-entrant and it will eventually
-      // be zombied when it is no longer seen on the stack. Note that the nmethod
-      // might be "entrant" and not on the stack and so could be zombied immediately
-      // but we can't tell because we don't track it on stack until it becomes
-      // non-entrant.
-
-      if (nm->is_not_entrant() && nm->can_not_entrant_be_converted()) {
-        nm->make_zombie();
-      } else {
-        nm->make_not_entrant();
-      }
-    }
-  }
-}
-
 void CodeCache::make_marked_nmethods_not_entrant() {
   assert_locked_or_safepoint(CodeCache_lock);
   FOR_ALL_ALIVE_NMETHODS(nm) {

src/share/vm/code/codeCache.hpp

@@ -179,7 +179,6 @@ class CodeCache : AllStatic {
 
   static void mark_all_nmethods_for_deoptimization();
   static int  mark_for_deoptimization(Method* dependee);
-  static void make_marked_nmethods_zombies();
   static void make_marked_nmethods_not_entrant();
 
     // tells how many nmethods have dependencies

src/share/vm/code/compiledIC.cpp

@@ -343,8 +343,8 @@ void CompiledIC::set_to_clean() {
     // Kill any leftover stub we might have too
     clear_ic_stub();
     if (is_optimized()) {
-    set_ic_destination(entry);
-  } else {
+      set_ic_destination(entry);
+    } else {
       set_ic_destination_and_value(entry, (void*)NULL);
     }
   } else {

src/share/vm/code/compiledIC.hpp

@@ -228,7 +228,7 @@ class CompiledIC: public ResourceObj {
   //
   // They all takes a TRAP argument, since they can cause a GC if the inline-cache buffer is full.
   //
-  void set_to_clean();  // Can only be called during a safepoint operation
+  void set_to_clean();
   void set_to_monomorphic(CompiledICInfo& info);
   void clear_ic_stub();
 

src/share/vm/code/nmethod.cpp

@@ -1162,7 +1162,6 @@ void nmethod::clear_ic_stubs() {
 
 
 void nmethod::cleanup_inline_caches() {
-
   assert_locked_or_safepoint(CompiledIC_lock);
 
   // If the method is not entrant or zombie then a JMP is plastered over the
@@ -1178,7 +1177,8 @@ void nmethod::cleanup_inline_caches() {
     // In fact, why are we bothering to look at oops in a non-entrant method??
   }
 
-  // Find all calls in an nmethod, and clear the ones that points to zombie methods
+  // Find all calls in an nmethod and clear the ones that point to non-entrant,
+  // zombie and unloaded nmethods.
   ResourceMark rm;
   RelocIterator iter(this, low_boundary);
   while(iter.next()) {
@@ -1190,7 +1190,7 @@ void nmethod::cleanup_inline_caches() {
         CodeBlob *cb = CodeCache::find_blob_unsafe(ic->ic_destination());
         if( cb != NULL && cb->is_nmethod() ) {
           nmethod* nm = (nmethod*)cb;
-          // Clean inline caches pointing to both zombie and not_entrant methods
+          // Clean inline caches pointing to zombie, non-entrant and unloaded methods
           if (!nm->is_in_use() || (nm->method()->code() != nm)) ic->set_to_clean();
         }
         break;
@@ -1200,7 +1200,7 @@ void nmethod::cleanup_inline_caches() {
         CodeBlob *cb = CodeCache::find_blob_unsafe(csc->destination());
         if( cb != NULL && cb->is_nmethod() ) {
           nmethod* nm = (nmethod*)cb;
-          // Clean inline caches pointing to both zombie and not_entrant methods
+          // Clean inline caches pointing to zombie, non-entrant and unloaded methods
           if (!nm->is_in_use() || (nm->method()->code() != nm)) csc->set_to_clean();
         }
         break;
@@ -2707,7 +2707,7 @@ void nmethod::verify() {
   // Hmm. OSR methods can be deopted but not marked as zombie or not_entrant
   // seems odd.
 
-  if( is_zombie() || is_not_entrant() )
+  if (is_zombie() || is_not_entrant() || is_unloaded())
     return;
 
   // Make sure all the entry points are correctly aligned for patching.

src/share/vm/prims/jvmtiRedefineClasses.cpp

@@ -3751,7 +3751,7 @@ void VM_RedefineClasses::flush_dependent_code(instanceKlassHandle k_h, TRAPS) {
     // Deoptimize all activations depending on marked nmethods
     Deoptimization::deoptimize_dependents();
 
-    // Make the dependent methods not entrant (in VM_Deoptimize they are made zombies)
+    // Make the dependent methods not entrant
     CodeCache::make_marked_nmethods_not_entrant();
 
     // From now on we know that the dependency information is complete

src/share/vm/runtime/vm_operations.cpp

@@ -106,8 +106,8 @@ void VM_Deoptimize::doit() {
   // Deoptimize all activations depending on marked nmethods
   Deoptimization::deoptimize_dependents();
 
-  // Make the dependent methods zombies
-  CodeCache::make_marked_nmethods_zombies();
+  // Make the dependent methods not entrant
+  CodeCache::make_marked_nmethods_not_entrant();
 }