1.1 --- /dev/null Thu Jan 01 00:00:00 1970 +0000
1.2 +++ b/src/share/vm/code/icBuffer.cpp Wed Apr 27 01:25:04 2016 +0800
1.3 @@ -0,0 +1,236 @@
1.4 +/*
1.5 + * Copyright (c) 1997, 2014, Oracle and/or its affiliates. All rights reserved.
1.6 + * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
1.7 + *
1.8 + * This code is free software; you can redistribute it and/or modify it
1.9 + * under the terms of the GNU General Public License version 2 only, as
1.10 + * published by the Free Software Foundation.
1.11 + *
1.12 + * This code is distributed in the hope that it will be useful, but WITHOUT
1.13 + * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
1.14 + * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License
1.15 + * version 2 for more details (a copy is included in the LICENSE file that
1.16 + * accompanied this code).
1.17 + *
1.18 + * You should have received a copy of the GNU General Public License version
1.19 + * 2 along with this work; if not, write to the Free Software Foundation,
1.20 + * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
1.21 + *
1.22 + * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA
1.23 + * or visit www.oracle.com if you need additional information or have any
1.24 + * questions.
1.25 + *
1.26 + */
1.27 +
1.28 +#include "precompiled.hpp"
1.29 +#include "code/codeCache.hpp"
1.30 +#include "code/compiledIC.hpp"
1.31 +#include "code/icBuffer.hpp"
1.32 +#include "code/nmethod.hpp"
1.33 +#include "code/scopeDesc.hpp"
1.34 +#include "gc_interface/collectedHeap.inline.hpp"
1.35 +#include "interpreter/interpreter.hpp"
1.36 +#include "interpreter/linkResolver.hpp"
1.37 +#include "memory/resourceArea.hpp"
1.38 +#include "memory/universe.inline.hpp"
1.39 +#include "oops/method.hpp"
1.40 +#include "oops/oop.inline.hpp"
1.41 +#include "oops/oop.inline2.hpp"
1.42 +#include "runtime/mutexLocker.hpp"
1.43 +#include "runtime/stubRoutines.hpp"
1.44 +
1.45 +PRAGMA_FORMAT_MUTE_WARNINGS_FOR_GCC
1.46 +
1.47 +DEF_STUB_INTERFACE(ICStub);
1.48 +
1.49 +StubQueue* InlineCacheBuffer::_buffer = NULL;
1.50 +ICStub* InlineCacheBuffer::_next_stub = NULL;
1.51 +
1.52 +CompiledICHolder* InlineCacheBuffer::_pending_released = NULL;
1.53 +int InlineCacheBuffer::_pending_count = 0;
1.54 +
1.55 +void ICStub::finalize() {
1.56 + if (!is_empty()) {
1.57 + ResourceMark rm;
1.58 + CompiledIC *ic = CompiledIC_at(CodeCache::find_nmethod(ic_site()), ic_site());
1.59 + assert(CodeCache::find_nmethod(ic->instruction_address()) != NULL, "inline cache in non-nmethod?");
1.60 +
1.61 + assert(this == ICStub_from_destination_address(ic->stub_address()), "wrong owner of ic buffer");
1.62 + ic->set_ic_destination_and_value(destination(), cached_value());
1.63 + }
1.64 +}
1.65 +
1.66 +
1.67 +address ICStub::destination() const {
1.68 + return InlineCacheBuffer::ic_buffer_entry_point(code_begin());
1.69 +}
1.70 +
1.71 +void* ICStub::cached_value() const {
1.72 + return InlineCacheBuffer::ic_buffer_cached_value(code_begin());
1.73 +}
1.74 +
1.75 +
1.76 +void ICStub::set_stub(CompiledIC *ic, void* cached_val, address dest_addr) {
1.77 + // We cannot store a pointer to the 'ic' object, since it is resource allocated. Instead we
1.78 + // store the location of the inline cache. Then we have enough information recreate the CompiledIC
1.79 + // object when we need to remove the stub.
1.80 + _ic_site = ic->instruction_address();
1.81 +
1.82 + // Assemble new stub
1.83 + InlineCacheBuffer::assemble_ic_buffer_code(code_begin(), cached_val, dest_addr);
1.84 + assert(destination() == dest_addr, "can recover destination");
1.85 + assert(cached_value() == cached_val, "can recover destination");
1.86 +}
1.87 +
1.88 +
1.89 +void ICStub::clear() {
1.90 + if (CompiledIC::is_icholder_entry(destination())) {
1.91 + InlineCacheBuffer::queue_for_release((CompiledICHolder*)cached_value());
1.92 + }
1.93 + _ic_site = NULL;
1.94 +}
1.95 +
1.96 +
1.97 +#ifndef PRODUCT
1.98 +// anybody calling to this stub will trap
1.99 +
1.100 +void ICStub::verify() {
1.101 +}
1.102 +
1.103 +void ICStub::print() {
1.104 + tty->print_cr("ICStub: site: " INTPTR_FORMAT, _ic_site);
1.105 +}
1.106 +#endif
1.107 +
1.108 +//-----------------------------------------------------------------------------------------------
1.109 +// Implementation of InlineCacheBuffer
1.110 +
1.111 +void InlineCacheBuffer::init_next_stub() {
1.112 + ICStub* ic_stub = (ICStub*)buffer()->request_committed (ic_stub_code_size());
1.113 + assert (ic_stub != NULL, "no room for a single stub");
1.114 + set_next_stub(ic_stub);
1.115 +}
1.116 +
1.117 +void InlineCacheBuffer::initialize() {
1.118 + if (_buffer != NULL) return; // already initialized
1.119 + _buffer = new StubQueue(new ICStubInterface, 10*K, InlineCacheBuffer_lock, "InlineCacheBuffer");
1.120 + assert (_buffer != NULL, "cannot allocate InlineCacheBuffer");
1.121 + init_next_stub();
1.122 +}
1.123 +
1.124 +
1.125 +ICStub* InlineCacheBuffer::new_ic_stub() {
1.126 + while (true) {
1.127 + ICStub* ic_stub = (ICStub*)buffer()->request_committed(ic_stub_code_size());
1.128 + if (ic_stub != NULL) {
1.129 + return ic_stub;
1.130 + }
1.131 + // we ran out of inline cache buffer space; must enter safepoint.
1.132 + // We do this by forcing a safepoint
1.133 + EXCEPTION_MARK;
1.134 +
1.135 + VM_ForceSafepoint vfs;
1.136 + VMThread::execute(&vfs);
1.137 + // We could potential get an async. exception at this point.
1.138 + // In that case we will rethrow it to ourselvs.
1.139 + if (HAS_PENDING_EXCEPTION) {
1.140 + oop exception = PENDING_EXCEPTION;
1.141 + CLEAR_PENDING_EXCEPTION;
1.142 + Thread::send_async_exception(JavaThread::current()->threadObj(), exception);
1.143 + }
1.144 + }
1.145 + ShouldNotReachHere();
1.146 + return NULL;
1.147 +}
1.148 +
1.149 +
1.150 +void InlineCacheBuffer::update_inline_caches() {
1.151 + if (buffer()->number_of_stubs() > 1) {
1.152 + if (TraceICBuffer) {
1.153 + tty->print_cr("[updating inline caches with %d stubs]", buffer()->number_of_stubs());
1.154 + }
1.155 + buffer()->remove_all();
1.156 + init_next_stub();
1.157 + }
1.158 + release_pending_icholders();
1.159 +}
1.160 +
1.161 +
1.162 +bool InlineCacheBuffer::contains(address instruction_address) {
1.163 + return buffer()->contains(instruction_address);
1.164 +}
1.165 +
1.166 +
1.167 +bool InlineCacheBuffer::is_empty() {
1.168 + return buffer()->number_of_stubs() == 1; // always has sentinel
1.169 +}
1.170 +
1.171 +
1.172 +void InlineCacheBuffer_init() {
1.173 + InlineCacheBuffer::initialize();
1.174 +}
1.175 +
1.176 +
1.177 +void InlineCacheBuffer::create_transition_stub(CompiledIC *ic, void* cached_value, address entry) {
1.178 + assert(!SafepointSynchronize::is_at_safepoint(), "should not be called during a safepoint");
1.179 + assert (CompiledIC_lock->is_locked(), "");
1.180 + if (TraceICBuffer) {
1.181 + tty->print_cr(" create transition stub for " INTPTR_FORMAT " destination " INTPTR_FORMAT " cached value " INTPTR_FORMAT,
1.182 + ic->instruction_address(), entry, cached_value);
1.183 + }
1.184 +
1.185 + // If an transition stub is already associate with the inline cache, then we remove the association.
1.186 + if (ic->is_in_transition_state()) {
1.187 + ICStub* old_stub = ICStub_from_destination_address(ic->stub_address());
1.188 + old_stub->clear();
1.189 + }
1.190 +
1.191 + // allocate and initialize new "out-of-line" inline-cache
1.192 + ICStub* ic_stub = get_next_stub();
1.193 + ic_stub->set_stub(ic, cached_value, entry);
1.194 +
1.195 + // Update inline cache in nmethod to point to new "out-of-line" allocated inline cache
1.196 + ic->set_ic_destination(ic_stub);
1.197 +
1.198 + set_next_stub(new_ic_stub()); // can cause safepoint synchronization
1.199 +}
1.200 +
1.201 +
1.202 +address InlineCacheBuffer::ic_destination_for(CompiledIC *ic) {
1.203 + ICStub* stub = ICStub_from_destination_address(ic->stub_address());
1.204 + return stub->destination();
1.205 +}
1.206 +
1.207 +
1.208 +void* InlineCacheBuffer::cached_value_for(CompiledIC *ic) {
1.209 + ICStub* stub = ICStub_from_destination_address(ic->stub_address());
1.210 + return stub->cached_value();
1.211 +}
1.212 +
1.213 +
1.214 +// Free CompiledICHolder*s that are no longer in use
1.215 +void InlineCacheBuffer::release_pending_icholders() {
1.216 + assert(SafepointSynchronize::is_at_safepoint(), "should only be called during a safepoint");
1.217 + CompiledICHolder* holder = _pending_released;
1.218 + _pending_released = NULL;
1.219 + while (holder != NULL) {
1.220 + CompiledICHolder* next = holder->next();
1.221 + delete holder;
1.222 + holder = next;
1.223 + _pending_count--;
1.224 + }
1.225 + assert(_pending_count == 0, "wrong count");
1.226 +}
1.227 +
1.228 +// Enqueue this icholder for release during the next safepoint. It's
1.229 +// not safe to free them until them since they might be visible to
1.230 +// another thread.
1.231 +void InlineCacheBuffer::queue_for_release(CompiledICHolder* icholder) {
1.232 + MutexLockerEx mex(InlineCacheBuffer_lock);
1.233 + icholder->set_next(_pending_released);
1.234 + _pending_released = icholder;
1.235 + _pending_count++;
1.236 + if (TraceICBuffer) {
1.237 + tty->print_cr("enqueueing icholder " INTPTR_FORMAT " to be freed", icholder);
1.238 + }
1.239 +}
