--- /dev/null Thu Jan 01 00:00:00 1970 +0000
+++ b/src/hotspot/share/code/icBuffer.cpp Tue Sep 12 19:03:39 2017 +0200
@@ -0,0 +1,233 @@
+/*
+ * Copyright (c) 1997, 2016, Oracle and/or its affiliates. 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
+ * under the terms of the GNU General Public License version 2 only, as
+ * published by the Free Software Foundation.
+ *
+ * This code is distributed in the hope that it will be useful, but WITHOUT
+ * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
+ * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License
+ * version 2 for more details (a copy is included in the LICENSE file that
+ * accompanied this code).
+ *
+ * You should have received a copy of the GNU General Public License version
+ * 2 along with this work; if not, write to the Free Software Foundation,
+ * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
+ *
+ * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA
+ * or visit www.oracle.com if you need additional information or have any
+ * questions.
+ *
+ */
+
+#include "precompiled.hpp"
+#include "code/codeCache.hpp"
+#include "code/compiledIC.hpp"
+#include "code/icBuffer.hpp"
+#include "code/nmethod.hpp"
+#include "code/scopeDesc.hpp"
+#include "gc/shared/collectedHeap.inline.hpp"
+#include "interpreter/interpreter.hpp"
+#include "interpreter/linkResolver.hpp"
+#include "memory/resourceArea.hpp"
+#include "memory/universe.inline.hpp"
+#include "oops/method.hpp"
+#include "oops/oop.inline.hpp"
+#include "runtime/mutexLocker.hpp"
+#include "runtime/stubRoutines.hpp"
+
+DEF_STUB_INTERFACE(ICStub);
+
+StubQueue* InlineCacheBuffer::_buffer = NULL;
+ICStub* InlineCacheBuffer::_next_stub = NULL;
+
+CompiledICHolder* InlineCacheBuffer::_pending_released = NULL;
+int InlineCacheBuffer::_pending_count = 0;
+
+void ICStub::finalize() {
+ if (!is_empty()) {
+ ResourceMark rm;
+ CompiledIC *ic = CompiledIC_at(CodeCache::find_compiled(ic_site()), ic_site());
+ assert(CodeCache::find_compiled(ic->instruction_address()) != NULL, "inline cache in non-compiled?");
+
+ assert(this == ICStub_from_destination_address(ic->stub_address()), "wrong owner of ic buffer");
+ ic->set_ic_destination_and_value(destination(), cached_value());
+ }
+}
+
+
+address ICStub::destination() const {
+ return InlineCacheBuffer::ic_buffer_entry_point(code_begin());
+}
+
+void* ICStub::cached_value() const {
+ return InlineCacheBuffer::ic_buffer_cached_value(code_begin());
+}
+
+
+void ICStub::set_stub(CompiledIC *ic, void* cached_val, address dest_addr) {
+ // We cannot store a pointer to the 'ic' object, since it is resource allocated. Instead we
+ // store the location of the inline cache. Then we have enough information recreate the CompiledIC
+ // object when we need to remove the stub.
+ _ic_site = ic->instruction_address();
+
+ // Assemble new stub
+ InlineCacheBuffer::assemble_ic_buffer_code(code_begin(), cached_val, dest_addr);
+ assert(destination() == dest_addr, "can recover destination");
+ assert(cached_value() == cached_val, "can recover destination");
+}
+
+
+void ICStub::clear() {
+ if (CompiledIC::is_icholder_entry(destination())) {
+ InlineCacheBuffer::queue_for_release((CompiledICHolder*)cached_value());
+ }
+ _ic_site = NULL;
+}
+
+
+#ifndef PRODUCT
+// anybody calling to this stub will trap
+
+void ICStub::verify() {
+}
+
+void ICStub::print() {
+ tty->print_cr("ICStub: site: " INTPTR_FORMAT, p2i(_ic_site));
+}
+#endif
+
+//-----------------------------------------------------------------------------------------------
+// Implementation of InlineCacheBuffer
+
+void InlineCacheBuffer::init_next_stub() {
+ ICStub* ic_stub = (ICStub*)buffer()->request_committed (ic_stub_code_size());
+ assert (ic_stub != NULL, "no room for a single stub");
+ set_next_stub(ic_stub);
+}
+
+void InlineCacheBuffer::initialize() {
+ if (_buffer != NULL) return; // already initialized
+ _buffer = new StubQueue(new ICStubInterface, 10*K, InlineCacheBuffer_lock, "InlineCacheBuffer");
+ assert (_buffer != NULL, "cannot allocate InlineCacheBuffer");
+ init_next_stub();
+}
+
+
+ICStub* InlineCacheBuffer::new_ic_stub() {
+ while (true) {
+ ICStub* ic_stub = (ICStub*)buffer()->request_committed(ic_stub_code_size());
+ if (ic_stub != NULL) {
+ return ic_stub;
+ }
+ // we ran out of inline cache buffer space; must enter safepoint.
+ // We do this by forcing a safepoint
+ EXCEPTION_MARK;
+
+ VM_ICBufferFull ibf;
+ VMThread::execute(&ibf);
+ // We could potential get an async. exception at this point.
+ // In that case we will rethrow it to ourselvs.
+ if (HAS_PENDING_EXCEPTION) {
+ oop exception = PENDING_EXCEPTION;
+ CLEAR_PENDING_EXCEPTION;
+ Thread::send_async_exception(JavaThread::current()->threadObj(), exception);
+ }
+ }
+ ShouldNotReachHere();
+ return NULL;
+}
+
+
+void InlineCacheBuffer::update_inline_caches() {
+ if (buffer()->number_of_stubs() > 1) {
+ if (TraceICBuffer) {
+ tty->print_cr("[updating inline caches with %d stubs]", buffer()->number_of_stubs());
+ }
+ buffer()->remove_all();
+ init_next_stub();
+ }
+ release_pending_icholders();
+}
+
+
+bool InlineCacheBuffer::contains(address instruction_address) {
+ return buffer()->contains(instruction_address);
+}
+
+
+bool InlineCacheBuffer::is_empty() {
+ return buffer()->number_of_stubs() == 1; // always has sentinel
+}
+
+
+void InlineCacheBuffer_init() {
+ InlineCacheBuffer::initialize();
+}
+
+
+void InlineCacheBuffer::create_transition_stub(CompiledIC *ic, void* cached_value, address entry) {
+ assert(!SafepointSynchronize::is_at_safepoint(), "should not be called during a safepoint");
+ assert (CompiledIC_lock->is_locked(), "");
+ if (TraceICBuffer) {
+ tty->print_cr(" create transition stub for " INTPTR_FORMAT " destination " INTPTR_FORMAT " cached value " INTPTR_FORMAT,
+ p2i(ic->instruction_address()), p2i(entry), p2i(cached_value));
+ }
+
+ // If an transition stub is already associate with the inline cache, then we remove the association.
+ if (ic->is_in_transition_state()) {
+ ICStub* old_stub = ICStub_from_destination_address(ic->stub_address());
+ old_stub->clear();
+ }
+
+ // allocate and initialize new "out-of-line" inline-cache
+ ICStub* ic_stub = get_next_stub();
+ ic_stub->set_stub(ic, cached_value, entry);
+
+ // Update inline cache in nmethod to point to new "out-of-line" allocated inline cache
+ ic->set_ic_destination(ic_stub);
+
+ set_next_stub(new_ic_stub()); // can cause safepoint synchronization
+}
+
+
+address InlineCacheBuffer::ic_destination_for(CompiledIC *ic) {
+ ICStub* stub = ICStub_from_destination_address(ic->stub_address());
+ return stub->destination();
+}
+
+
+void* InlineCacheBuffer::cached_value_for(CompiledIC *ic) {
+ ICStub* stub = ICStub_from_destination_address(ic->stub_address());
+ return stub->cached_value();
+}
+
+
+// Free CompiledICHolder*s that are no longer in use
+void InlineCacheBuffer::release_pending_icholders() {
+ assert(SafepointSynchronize::is_at_safepoint(), "should only be called during a safepoint");
+ CompiledICHolder* holder = _pending_released;
+ _pending_released = NULL;
+ while (holder != NULL) {
+ CompiledICHolder* next = holder->next();
+ delete holder;
+ holder = next;
+ _pending_count--;
+ }
+ assert(_pending_count == 0, "wrong count");
+}
+
+// Enqueue this icholder for release during the next safepoint. It's
+// not safe to free them until them since they might be visible to
+// another thread.
+void InlineCacheBuffer::queue_for_release(CompiledICHolder* icholder) {
+ MutexLockerEx mex(InlineCacheBuffer_lock);
+ icholder->set_next(_pending_released);
+ _pending_released = icholder;
+ _pending_count++;
+ if (TraceICBuffer) {
+ tty->print_cr("enqueueing icholder " INTPTR_FORMAT " to be freed", p2i(icholder));
+ }
+}