--- old/src/share/vm/code/codeCache.cpp 2015-08-28 10:34:22.818558771 +0200 +++ new/src/share/vm/code/codeCache.cpp 2015-08-28 10:34:22.746558774 +0200 @@ -745,13 +745,12 @@ void CodeCache::gc_epilogue() { assert_locked_or_safepoint(CodeCache_lock); - NMethodIterator iter; - while(iter.next()) { - nmethod* nm = iter.method(); - 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. + NOT_DEBUG(if (needs_cache_clean())) { + NMethodIterator iter; + while(iter.next_alive()) { + nmethod* nm = iter.method(); + assert(!nm->is_unloaded(), "Tautology"); + DEBUG_ONLY(if (needs_cache_clean())) { nm->cleanup_inline_caches(); } DEBUG_ONLY(nm->verify()); --- old/src/share/vm/code/compiledIC.cpp 2015-08-28 10:34:23.098558758 +0200 +++ new/src/share/vm/code/compiledIC.cpp 2015-08-28 10:34:23.026558761 +0200 @@ -287,6 +287,7 @@ assert( is_c1_method || !is_monomorphic || is_optimized() || + !caller->is_alive() || (cached_metadata() != NULL && cached_metadata()->is_klass()), "sanity check"); #endif // ASSERT return is_monomorphic; @@ -321,7 +322,7 @@ } -void CompiledIC::set_to_clean() { +void CompiledIC::set_to_clean(bool in_use) { assert(SafepointSynchronize::is_at_safepoint() || CompiledIC_lock->is_locked() , "MT-unsafe call"); if (TraceInlineCacheClearing || TraceICs) { tty->print_cr("IC@" INTPTR_FORMAT ": set to clean", p2i(instruction_address())); @@ -337,7 +338,7 @@ // A zombie transition will always be safe, since the metadata has already been set to NULL, so // we only need to patch the destination - bool safe_transition = is_optimized() || SafepointSynchronize::is_at_safepoint(); + bool safe_transition = !in_use || is_optimized() || SafepointSynchronize::is_at_safepoint(); if (safe_transition) { // Kill any leftover stub we might have too --- old/src/share/vm/code/compiledIC.hpp 2015-08-28 10:34:23.378558745 +0200 +++ new/src/share/vm/code/compiledIC.hpp 2015-08-28 10:34:23.302558748 +0200 @@ -214,7 +214,7 @@ // // They all takes a TRAP argument, since they can cause a GC if the inline-cache buffer is full. // - void set_to_clean(); + void set_to_clean(bool in_use = true); void set_to_monomorphic(CompiledICInfo& info); void clear_ic_stub(); --- old/src/share/vm/code/nmethod.cpp 2015-08-28 10:34:23.666558731 +0200 +++ new/src/share/vm/code/nmethod.cpp 2015-08-28 10:34:23.586558735 +0200 @@ -1050,7 +1050,7 @@ if( cb != NULL && cb->is_nmethod() ) { nmethod* nm = (nmethod*)cb; // Clean inline caches pointing to zombie, non-entrant and unloaded methods - if (!nm->is_in_use() || (nm->method()->code() != nm)) ic->set_to_clean(); + if (!nm->is_in_use() || (nm->method()->code() != nm)) ic->set_to_clean(is_alive()); } break; } @@ -1150,7 +1150,7 @@ // Tell if a non-entrant method can be converted to a zombie (i.e., // there are no activations on the stack, not in use by the VM, // and not in use by the ServiceThread) -bool nmethod::can_not_entrant_be_converted() { +bool nmethod::can_convert_to_zombie() { assert(is_not_entrant(), "must be a non-entrant method"); // Since the nmethod sweeper only does partial sweep the sweeper's traversal --- old/src/share/vm/code/nmethod.hpp 2015-08-28 10:34:23.978558717 +0200 +++ new/src/share/vm/code/nmethod.hpp 2015-08-28 10:34:23.902558720 +0200 @@ -577,7 +577,7 @@ // See comment at definition of _last_seen_on_stack void mark_as_seen_on_stack(); - bool can_not_entrant_be_converted(); + bool can_convert_to_zombie(); // Evolution support. We make old (discarded) compiled methods point to new Method*s. void set_method(Method* method) { _method = method; } --- old/src/share/vm/runtime/sweeper.cpp 2015-08-28 10:34:24.266558703 +0200 +++ new/src/share/vm/runtime/sweeper.cpp 2015-08-28 10:34:24.194558707 +0200 @@ -611,7 +611,7 @@ } else if (nm->is_not_entrant()) { // If there are no current activations of this method on the // stack we can safely convert it to a zombie method - if (nm->can_not_entrant_be_converted()) { + if (nm->can_convert_to_zombie()) { // Clear ICStubs to prevent back patching stubs of zombie or unloaded // nmethods during the next safepoint (see ICStub::finalize). { @@ -645,6 +645,12 @@ assert(result == None, "sanity"); result = Flushed; } else { + { + // Clean ICs of unloaded nmethods as well because they may reference other + // unloaded nmethods that may be flushed earlier in the sweeper cycle. + MutexLocker cl(CompiledIC_lock); + nm->cleanup_inline_caches(); + } // Code cache state change is tracked in make_zombie() nm->make_zombie(); SWEEP(nm);