duke@435: /*
duke@435:  * Copyright 1997-2006 Sun Microsystems, Inc.  All Rights Reserved.
duke@435:  * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
duke@435:  *
duke@435:  * This code is free software; you can redistribute it and/or modify it
duke@435:  * under the terms of the GNU General Public License version 2 only, as
duke@435:  * published by the Free Software Foundation.
duke@435:  *
duke@435:  * This code is distributed in the hope that it will be useful, but WITHOUT
duke@435:  * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
duke@435:  * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License
duke@435:  * version 2 for more details (a copy is included in the LICENSE file that
duke@435:  * accompanied this code).
duke@435:  *
duke@435:  * You should have received a copy of the GNU General Public License version
duke@435:  * 2 along with this work; if not, write to the Free Software Foundation,
duke@435:  * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
duke@435:  *
duke@435:  * Please contact Sun Microsystems, Inc., 4150 Network Circle, Santa Clara,
duke@435:  * CA 95054 USA or visit www.sun.com if you need additional information or
duke@435:  * have any questions.
duke@435:  *
duke@435:  */
duke@435: 
duke@435: #include "incls/_precompiled.incl"
duke@435: #include "incls/_vtableStubs.cpp.incl"
duke@435: 
duke@435: // -----------------------------------------------------------------------------------------
duke@435: // Implementation of VtableStub
duke@435: 
duke@435: address VtableStub::_chunk             = NULL;
duke@435: address VtableStub::_chunk_end         = NULL;
duke@435: VMReg   VtableStub::_receiver_location = VMRegImpl::Bad();
duke@435: 
duke@435: static int num_vtable_chunks = 0;
duke@435: 
duke@435: 
duke@435: void* VtableStub::operator new(size_t size, int code_size) {
duke@435:   assert(size == sizeof(VtableStub), "mismatched size");
duke@435:   num_vtable_chunks++;
duke@435:   // compute real VtableStub size (rounded to nearest word)
duke@435:   const int real_size = round_to(code_size + sizeof(VtableStub), wordSize);
duke@435:   // malloc them in chunks to minimize header overhead
duke@435:   const int chunk_factor = 32;
duke@435:   if (_chunk == NULL || _chunk + real_size > _chunk_end) {
duke@435:     const int bytes = chunk_factor * real_size + pd_code_alignment();
duke@435:     BufferBlob* blob = BufferBlob::create("vtable chunks", bytes);
duke@435:     if( blob == NULL ) vm_exit_out_of_memory1(bytes, "CodeCache: no room for %s", "vtable chunks");
duke@435:     _chunk = blob->instructions_begin();
duke@435:     _chunk_end = _chunk + bytes;
duke@435:     VTune::register_stub("vtable stub", _chunk, _chunk_end);
duke@435:     Forte::register_stub("vtable stub", _chunk, _chunk_end);
duke@435:     // Notify JVMTI about this stub. The event will be recorded by the enclosing
duke@435:     // JvmtiDynamicCodeEventCollector and posted when this thread has released
duke@435:     // all locks.
duke@435:     if (JvmtiExport::should_post_dynamic_code_generated()) {
duke@435:       JvmtiExport::post_dynamic_code_generated_while_holding_locks("vtable stub", _chunk, _chunk_end);
duke@435:     }
duke@435:     align_chunk();
duke@435:   }
duke@435:   assert(_chunk + real_size <= _chunk_end, "bad allocation");
duke@435:   void* res = _chunk;
duke@435:   _chunk += real_size;
duke@435:   align_chunk();
duke@435:  return res;
duke@435: }
duke@435: 
duke@435: 
duke@435: void VtableStub::print() {
duke@435:   tty->print("vtable stub (index = %d, receiver_location = %d, code = [" INTPTR_FORMAT ", " INTPTR_FORMAT "[)",
duke@435:              index(), receiver_location(), code_begin(), code_end());
duke@435: }
duke@435: 
duke@435: 
duke@435: // -----------------------------------------------------------------------------------------
duke@435: // Implementation of VtableStubs
duke@435: //
duke@435: // For each hash value there's a linked list of vtable stubs (with that
duke@435: // hash value). Each list is anchored in a little hash _table, indexed
duke@435: // by that hash value.
duke@435: 
duke@435: VtableStub* VtableStubs::_table[VtableStubs::N];
duke@435: int VtableStubs::_number_of_vtable_stubs = 0;
duke@435: 
duke@435: 
duke@435: void VtableStubs::initialize() {
duke@435:   VtableStub::_receiver_location = SharedRuntime::name_for_receiver();
duke@435:   {
duke@435:     MutexLocker ml(VtableStubs_lock);
duke@435:     assert(_number_of_vtable_stubs == 0, "potential performance bug: VtableStubs initialized more than once");
duke@435:     assert(is_power_of_2(N), "N must be a power of 2");
duke@435:     for (int i = 0; i < N; i++) {
duke@435:       _table[i] = NULL;
duke@435:     }
duke@435:   }
duke@435: }
duke@435: 
duke@435: 
duke@435: address VtableStubs::create_stub(bool is_vtable_stub, int vtable_index, methodOop method) {
duke@435:   assert(vtable_index >= 0, "must be positive");
duke@435: 
duke@435:   VtableStub* s = ShareVtableStubs ? lookup(is_vtable_stub, vtable_index) : NULL;
duke@435:   if (s == NULL) {
duke@435:     if (is_vtable_stub) {
duke@435:       s = create_vtable_stub(vtable_index);
duke@435:     } else {
duke@435:       s = create_itable_stub(vtable_index);
duke@435:     }
duke@435:     enter(is_vtable_stub, vtable_index, s);
duke@435:     if (PrintAdapterHandlers) {
duke@435:       tty->print_cr("Decoding VtableStub %s[%d]@%d",
duke@435:                     is_vtable_stub? "vtbl": "itbl", vtable_index, VtableStub::receiver_location());
duke@435:       Disassembler::decode(s->code_begin(), s->code_end());
duke@435:     }
duke@435:   }
duke@435:   return s->entry_point();
duke@435: }
duke@435: 
duke@435: 
duke@435: inline uint VtableStubs::hash(bool is_vtable_stub, int vtable_index){
duke@435:   // Assumption: receiver_location < 4 in most cases.
duke@435:   int hash = ((vtable_index << 2) ^ VtableStub::receiver_location()->value()) + vtable_index;
duke@435:   return (is_vtable_stub ? ~hash : hash)  & mask;
duke@435: }
duke@435: 
duke@435: 
duke@435: VtableStub* VtableStubs::lookup(bool is_vtable_stub, int vtable_index) {
duke@435:   MutexLocker ml(VtableStubs_lock);
duke@435:   unsigned hash = VtableStubs::hash(is_vtable_stub, vtable_index);
duke@435:   VtableStub* s = _table[hash];
duke@435:   while( s && !s->matches(is_vtable_stub, vtable_index)) s = s->next();
duke@435:   return s;
duke@435: }
duke@435: 
duke@435: 
duke@435: void VtableStubs::enter(bool is_vtable_stub, int vtable_index, VtableStub* s) {
duke@435:   MutexLocker ml(VtableStubs_lock);
duke@435:   assert(s->matches(is_vtable_stub, vtable_index), "bad vtable stub");
duke@435:   unsigned int h = VtableStubs::hash(is_vtable_stub, vtable_index);
duke@435:   // enter s at the beginning of the corresponding list
duke@435:   s->set_next(_table[h]);
duke@435:   _table[h] = s;
duke@435:   _number_of_vtable_stubs++;
duke@435: }
duke@435: 
duke@435: 
duke@435: bool VtableStubs::is_entry_point(address pc) {
duke@435:   MutexLocker ml(VtableStubs_lock);
duke@435:   VtableStub* stub = (VtableStub*)(pc - VtableStub::entry_offset());
duke@435:   uint hash = VtableStubs::hash(stub->is_vtable_stub(), stub->index());
duke@435:   VtableStub* s;
duke@435:   for (s = _table[hash]; s != NULL && s != stub; s = s->next()) {}
duke@435:   return s == stub;
duke@435: }
duke@435: 
duke@435: 
duke@435: bool VtableStubs::contains(address pc) {
duke@435:   // simple solution for now - we may want to use
duke@435:   // a faster way if this function is called often
duke@435:   return stub_containing(pc) != NULL;
duke@435: }
duke@435: 
duke@435: 
duke@435: VtableStub* VtableStubs::stub_containing(address pc) {
duke@435:   // Note: No locking needed since any change to the data structure
duke@435:   //       happens with an atomic store into it (we don't care about
duke@435:   //       consistency with the _number_of_vtable_stubs counter).
duke@435:   for (int i = 0; i < N; i++) {
duke@435:     for (VtableStub* s = _table[i]; s != NULL; s = s->next()) {
duke@435:       if (s->contains(pc)) return s;
duke@435:     }
duke@435:   }
duke@435:   return NULL;
duke@435: }
duke@435: 
duke@435: void vtableStubs_init() {
duke@435:   VtableStubs::initialize();
duke@435: }
duke@435: 
duke@435: 
duke@435: //-----------------------------------------------------------------------------------------------------
duke@435: // Non-product code
duke@435: #ifndef PRODUCT
duke@435: 
duke@435: extern "C" void bad_compiled_vtable_index(JavaThread* thread, oop receiver, int index) {
duke@435:   ResourceMark rm;
duke@435:   HandleMark hm;
duke@435:   klassOop klass = receiver->klass();
duke@435:   instanceKlass* ik = instanceKlass::cast(klass);
duke@435:   klassVtable* vt = ik->vtable();
duke@435:   klass->print();
duke@435:   fatal3("bad compiled vtable dispatch: receiver " INTPTR_FORMAT ", index %d (vtable length %d)", (address)receiver, index, vt->length());
duke@435: }
duke@435: 
duke@435: #endif // Product