icBuffer.cpp revision 1472:c18cbe5936b8
1/* 2 * Copyright (c) 1997, 2006, Oracle and/or its affiliates. All rights reserved. 3 * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER. 4 * 5 * This code is free software; you can redistribute it and/or modify it 6 * under the terms of the GNU General Public License version 2 only, as 7 * published by the Free Software Foundation. 8 * 9 * This code is distributed in the hope that it will be useful, but WITHOUT 10 * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or 11 * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License 12 * version 2 for more details (a copy is included in the LICENSE file that 13 * accompanied this code). 14 * 15 * You should have received a copy of the GNU General Public License version 16 * 2 along with this work; if not, write to the Free Software Foundation, 17 * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA. 18 * 19 * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA 20 * or visit www.oracle.com if you need additional information or have any 21 * questions. 22 * 23 */ 24 25#include "incls/_precompiled.incl" 26#include "incls/_icBuffer.cpp.incl" 27 28 29DEF_STUB_INTERFACE(ICStub); 30 31StubQueue* InlineCacheBuffer::_buffer = NULL; 32ICStub* InlineCacheBuffer::_next_stub = NULL; 33 34 35void ICStub::finalize() { 36 if (!is_empty()) { 37 ResourceMark rm; 38 CompiledIC *ic = CompiledIC_at(ic_site()); 39 assert(CodeCache::find_nmethod(ic->instruction_address()) != NULL, "inline cache in non-nmethod?"); 40 41 assert(this == ICStub_from_destination_address(ic->stub_address()), "wrong owner of ic buffer"); 42 ic->set_cached_oop(cached_oop()); 43 ic->set_ic_destination(destination()); 44 } 45} 46 47 48address ICStub::destination() const { 49 return InlineCacheBuffer::ic_buffer_entry_point(code_begin()); 50} 51 52oop ICStub::cached_oop() const { 53 return InlineCacheBuffer::ic_buffer_cached_oop(code_begin()); 54} 55 56 57void ICStub::set_stub(CompiledIC *ic, oop cached_value, address dest_addr) { 58 // We cannot store a pointer to the 'ic' object, since it is resource allocated. Instead we 59 // store the location of the inline cache. Then we have enough information recreate the CompiledIC 60 // object when we need to remove the stub. 61 _ic_site = ic->instruction_address(); 62 63 // Assemble new stub 64 InlineCacheBuffer::assemble_ic_buffer_code(code_begin(), cached_value, dest_addr); 65 assert(destination() == dest_addr, "can recover destination"); 66 assert(cached_oop() == cached_value, "can recover destination"); 67} 68 69 70void ICStub::clear() { 71 _ic_site = NULL; 72} 73 74 75#ifndef PRODUCT 76// anybody calling to this stub will trap 77 78void ICStub::verify() { 79} 80 81void ICStub::print() { 82 tty->print_cr("ICStub: site: " INTPTR_FORMAT, _ic_site); 83} 84#endif 85 86//----------------------------------------------------------------------------------------------- 87// Implementation of InlineCacheBuffer 88 89void InlineCacheBuffer::init_next_stub() { 90 ICStub* ic_stub = (ICStub*)buffer()->request_committed (ic_stub_code_size()); 91 assert (ic_stub != NULL, "no room for a single stub"); 92 set_next_stub(ic_stub); 93} 94 95void InlineCacheBuffer::initialize() { 96 if (_buffer != NULL) return; // already initialized 97 _buffer = new StubQueue(new ICStubInterface, 10*K, InlineCacheBuffer_lock, "InlineCacheBuffer"); 98 assert (_buffer != NULL, "cannot allocate InlineCacheBuffer"); 99 init_next_stub(); 100} 101 102 103ICStub* InlineCacheBuffer::new_ic_stub() { 104 while (true) { 105 ICStub* ic_stub = (ICStub*)buffer()->request_committed(ic_stub_code_size()); 106 if (ic_stub != NULL) { 107 return ic_stub; 108 } 109 // we ran out of inline cache buffer space; must enter safepoint. 110 // We do this by forcing a safepoint 111 EXCEPTION_MARK; 112 113 VM_ForceSafepoint vfs; 114 VMThread::execute(&vfs); 115 // We could potential get an async. exception at this point. 116 // In that case we will rethrow it to ourselvs. 117 if (HAS_PENDING_EXCEPTION) { 118 oop exception = PENDING_EXCEPTION; 119 CLEAR_PENDING_EXCEPTION; 120 Thread::send_async_exception(JavaThread::current()->threadObj(), exception); 121 } 122 } 123 ShouldNotReachHere(); 124 return NULL; 125} 126 127 128void InlineCacheBuffer::update_inline_caches() { 129 if (buffer()->number_of_stubs() > 1) { 130 if (TraceICBuffer) { 131 tty->print_cr("[updating inline caches with %d stubs]", buffer()->number_of_stubs()); 132 } 133 buffer()->remove_all(); 134 init_next_stub(); 135 } 136} 137 138 139bool InlineCacheBuffer::contains(address instruction_address) { 140 return buffer()->contains(instruction_address); 141} 142 143 144bool InlineCacheBuffer::is_empty() { 145 return buffer()->number_of_stubs() == 1; // always has sentinel 146} 147 148 149void InlineCacheBuffer_init() { 150 InlineCacheBuffer::initialize(); 151} 152 153 154void InlineCacheBuffer::create_transition_stub(CompiledIC *ic, oop cached_oop, address entry) { 155 assert(!SafepointSynchronize::is_at_safepoint(), "should not be called during a safepoint"); 156 assert (CompiledIC_lock->is_locked(), ""); 157 assert(cached_oop == NULL || cached_oop->is_perm(), "must belong to perm. space"); 158 if (TraceICBuffer) { tty->print_cr(" create transition stub for " INTPTR_FORMAT, ic->instruction_address()); } 159 160 // If an transition stub is already associate with the inline cache, then we remove the association. 161 if (ic->is_in_transition_state()) { 162 ICStub* old_stub = ICStub_from_destination_address(ic->stub_address()); 163 old_stub->clear(); 164 } 165 166 // allocate and initialize new "out-of-line" inline-cache 167 ICStub* ic_stub = get_next_stub(); 168 ic_stub->set_stub(ic, cached_oop, entry); 169 170 // Update inline cache in nmethod to point to new "out-of-line" allocated inline cache 171 ic->set_ic_destination(ic_stub->code_begin()); 172 173 set_next_stub(new_ic_stub()); // can cause safepoint synchronization 174} 175 176 177address InlineCacheBuffer::ic_destination_for(CompiledIC *ic) { 178 ICStub* stub = ICStub_from_destination_address(ic->stub_address()); 179 return stub->destination(); 180} 181 182 183oop InlineCacheBuffer::cached_oop_for(CompiledIC *ic) { 184 ICStub* stub = ICStub_from_destination_address(ic->stub_address()); 185 return stub->cached_oop(); 186} 187