vtableStubs.cpp revision 0:a61af66fc99e
1/* 2 * Copyright 1997-2006 Sun Microsystems, Inc. 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 Sun Microsystems, Inc., 4150 Network Circle, Santa Clara, 20 * CA 95054 USA or visit www.sun.com if you need additional information or 21 * have any questions. 22 * 23 */ 24 25#include "incls/_precompiled.incl" 26#include "incls/_vtableStubs.cpp.incl" 27 28// ----------------------------------------------------------------------------------------- 29// Implementation of VtableStub 30 31address VtableStub::_chunk = NULL; 32address VtableStub::_chunk_end = NULL; 33VMReg VtableStub::_receiver_location = VMRegImpl::Bad(); 34 35static int num_vtable_chunks = 0; 36 37 38void* VtableStub::operator new(size_t size, int code_size) { 39 assert(size == sizeof(VtableStub), "mismatched size"); 40 num_vtable_chunks++; 41 // compute real VtableStub size (rounded to nearest word) 42 const int real_size = round_to(code_size + sizeof(VtableStub), wordSize); 43 // malloc them in chunks to minimize header overhead 44 const int chunk_factor = 32; 45 if (_chunk == NULL || _chunk + real_size > _chunk_end) { 46 const int bytes = chunk_factor * real_size + pd_code_alignment(); 47 BufferBlob* blob = BufferBlob::create("vtable chunks", bytes); 48 if( blob == NULL ) vm_exit_out_of_memory1(bytes, "CodeCache: no room for %s", "vtable chunks"); 49 _chunk = blob->instructions_begin(); 50 _chunk_end = _chunk + bytes; 51 VTune::register_stub("vtable stub", _chunk, _chunk_end); 52 Forte::register_stub("vtable stub", _chunk, _chunk_end); 53 // Notify JVMTI about this stub. The event will be recorded by the enclosing 54 // JvmtiDynamicCodeEventCollector and posted when this thread has released 55 // all locks. 56 if (JvmtiExport::should_post_dynamic_code_generated()) { 57 JvmtiExport::post_dynamic_code_generated_while_holding_locks("vtable stub", _chunk, _chunk_end); 58 } 59 align_chunk(); 60 } 61 assert(_chunk + real_size <= _chunk_end, "bad allocation"); 62 void* res = _chunk; 63 _chunk += real_size; 64 align_chunk(); 65 return res; 66} 67 68 69void VtableStub::print() { 70 tty->print("vtable stub (index = %d, receiver_location = %d, code = [" INTPTR_FORMAT ", " INTPTR_FORMAT "[)", 71 index(), receiver_location(), code_begin(), code_end()); 72} 73 74 75// ----------------------------------------------------------------------------------------- 76// Implementation of VtableStubs 77// 78// For each hash value there's a linked list of vtable stubs (with that 79// hash value). Each list is anchored in a little hash _table, indexed 80// by that hash value. 81 82VtableStub* VtableStubs::_table[VtableStubs::N]; 83int VtableStubs::_number_of_vtable_stubs = 0; 84 85 86void VtableStubs::initialize() { 87 VtableStub::_receiver_location = SharedRuntime::name_for_receiver(); 88 { 89 MutexLocker ml(VtableStubs_lock); 90 assert(_number_of_vtable_stubs == 0, "potential performance bug: VtableStubs initialized more than once"); 91 assert(is_power_of_2(N), "N must be a power of 2"); 92 for (int i = 0; i < N; i++) { 93 _table[i] = NULL; 94 } 95 } 96} 97 98 99address VtableStubs::create_stub(bool is_vtable_stub, int vtable_index, methodOop method) { 100 assert(vtable_index >= 0, "must be positive"); 101 102 VtableStub* s = ShareVtableStubs ? lookup(is_vtable_stub, vtable_index) : NULL; 103 if (s == NULL) { 104 if (is_vtable_stub) { 105 s = create_vtable_stub(vtable_index); 106 } else { 107 s = create_itable_stub(vtable_index); 108 } 109 enter(is_vtable_stub, vtable_index, s); 110#ifndef PRODUCT 111 if (PrintAdapterHandlers) { 112 tty->print_cr("Decoding VtableStub %s[%d]@%d", 113 is_vtable_stub? "vtbl": "itbl", vtable_index, VtableStub::receiver_location()); 114 Disassembler::decode(s->code_begin(), s->code_end()); 115 } 116#endif 117 } 118 return s->entry_point(); 119} 120 121 122inline uint VtableStubs::hash(bool is_vtable_stub, int vtable_index){ 123 // Assumption: receiver_location < 4 in most cases. 124 int hash = ((vtable_index << 2) ^ VtableStub::receiver_location()->value()) + vtable_index; 125 return (is_vtable_stub ? ~hash : hash) & mask; 126} 127 128 129VtableStub* VtableStubs::lookup(bool is_vtable_stub, int vtable_index) { 130 MutexLocker ml(VtableStubs_lock); 131 unsigned hash = VtableStubs::hash(is_vtable_stub, vtable_index); 132 VtableStub* s = _table[hash]; 133 while( s && !s->matches(is_vtable_stub, vtable_index)) s = s->next(); 134 return s; 135} 136 137 138void VtableStubs::enter(bool is_vtable_stub, int vtable_index, VtableStub* s) { 139 MutexLocker ml(VtableStubs_lock); 140 assert(s->matches(is_vtable_stub, vtable_index), "bad vtable stub"); 141 unsigned int h = VtableStubs::hash(is_vtable_stub, vtable_index); 142 // enter s at the beginning of the corresponding list 143 s->set_next(_table[h]); 144 _table[h] = s; 145 _number_of_vtable_stubs++; 146} 147 148 149bool VtableStubs::is_entry_point(address pc) { 150 MutexLocker ml(VtableStubs_lock); 151 VtableStub* stub = (VtableStub*)(pc - VtableStub::entry_offset()); 152 uint hash = VtableStubs::hash(stub->is_vtable_stub(), stub->index()); 153 VtableStub* s; 154 for (s = _table[hash]; s != NULL && s != stub; s = s->next()) {} 155 return s == stub; 156} 157 158 159bool VtableStubs::contains(address pc) { 160 // simple solution for now - we may want to use 161 // a faster way if this function is called often 162 return stub_containing(pc) != NULL; 163} 164 165 166VtableStub* VtableStubs::stub_containing(address pc) { 167 // Note: No locking needed since any change to the data structure 168 // happens with an atomic store into it (we don't care about 169 // consistency with the _number_of_vtable_stubs counter). 170 for (int i = 0; i < N; i++) { 171 for (VtableStub* s = _table[i]; s != NULL; s = s->next()) { 172 if (s->contains(pc)) return s; 173 } 174 } 175 return NULL; 176} 177 178void vtableStubs_init() { 179 VtableStubs::initialize(); 180} 181 182 183//----------------------------------------------------------------------------------------------------- 184// Non-product code 185#ifndef PRODUCT 186 187extern "C" void bad_compiled_vtable_index(JavaThread* thread, oop receiver, int index) { 188 ResourceMark rm; 189 HandleMark hm; 190 klassOop klass = receiver->klass(); 191 instanceKlass* ik = instanceKlass::cast(klass); 192 klassVtable* vt = ik->vtable(); 193 klass->print(); 194 fatal3("bad compiled vtable dispatch: receiver " INTPTR_FORMAT ", index %d (vtable length %d)", (address)receiver, index, vt->length()); 195} 196 197#endif // Product 198