Mercurial > jdk8-mips64-public > hotspot / file revision

 /*

  * Copyright (c) 1997, 2009, 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 "incls/_precompiled.incl"

 #include "incls/_vtableStubs.cpp.incl"

 // -----------------------------------------------------------------------------------------

 // Implementation of VtableStub

 address VtableStub::_chunk             = NULL;

 address VtableStub::_chunk_end         = NULL;

 VMReg   VtableStub::_receiver_location = VMRegImpl::Bad();

 static int num_vtable_chunks = 0;

 void* VtableStub::operator new(size_t size, int code_size) {

   assert(size == sizeof(VtableStub), "mismatched size");

   num_vtable_chunks++;

   // compute real VtableStub size (rounded to nearest word)

   const int real_size = round_to(code_size + sizeof(VtableStub), wordSize);

   // malloc them in chunks to minimize header overhead

   const int chunk_factor = 32;

   if (_chunk == NULL || _chunk + real_size > _chunk_end) {

     const int bytes = chunk_factor * real_size + pd_code_alignment();

     BufferBlob* blob = BufferBlob::create("vtable chunks", bytes);

     if (blob == NULL) {

       vm_exit_out_of_memory(bytes, "CodeCache: no room for vtable chunks");

     }

     _chunk = blob->instructions_begin();

     _chunk_end = _chunk + bytes;

     VTune::register_stub("vtable stub", _chunk, _chunk_end);

     Forte::register_stub("vtable stub", _chunk, _chunk_end);

     // Notify JVMTI about this stub. The event will be recorded by the enclosing

     // JvmtiDynamicCodeEventCollector and posted when this thread has released

     // all locks.

     if (JvmtiExport::should_post_dynamic_code_generated()) {

       JvmtiExport::post_dynamic_code_generated_while_holding_locks("vtable stub", _chunk, _chunk_end);

     }

     align_chunk();

   }

   assert(_chunk + real_size <= _chunk_end, "bad allocation");

   void* res = _chunk;

   _chunk += real_size;

   align_chunk();

  return res;

 }

 void VtableStub::print() {

   tty->print("vtable stub (index = %d, receiver_location = %d, code = [" INTPTR_FORMAT ", " INTPTR_FORMAT "[)",

              index(), receiver_location(), code_begin(), code_end());

 }

 // -----------------------------------------------------------------------------------------

 // Implementation of VtableStubs

 //

 // For each hash value there's a linked list of vtable stubs (with that

 // hash value). Each list is anchored in a little hash _table, indexed

 // by that hash value.

 VtableStub* VtableStubs::_table[VtableStubs::N];

 int VtableStubs::_number_of_vtable_stubs = 0;

 void VtableStubs::initialize() {

   VtableStub::_receiver_location = SharedRuntime::name_for_receiver();

   {

     MutexLocker ml(VtableStubs_lock);

     assert(_number_of_vtable_stubs == 0, "potential performance bug: VtableStubs initialized more than once");

     assert(is_power_of_2(N), "N must be a power of 2");

     for (int i = 0; i < N; i++) {

       _table[i] = NULL;

     }

   }

 }

 address VtableStubs::create_stub(bool is_vtable_stub, int vtable_index, methodOop method) {

   assert(vtable_index >= 0, "must be positive");

   VtableStub* s = ShareVtableStubs ? lookup(is_vtable_stub, vtable_index) : NULL;

   if (s == NULL) {

     if (is_vtable_stub) {

       s = create_vtable_stub(vtable_index);

     } else {

       s = create_itable_stub(vtable_index);

     }

     enter(is_vtable_stub, vtable_index, s);

     if (PrintAdapterHandlers) {

       tty->print_cr("Decoding VtableStub %s[%d]@%d",

                     is_vtable_stub? "vtbl": "itbl", vtable_index, VtableStub::receiver_location());

       Disassembler::decode(s->code_begin(), s->code_end());

     }

   }

   return s->entry_point();

 }

 inline uint VtableStubs::hash(bool is_vtable_stub, int vtable_index){

   // Assumption: receiver_location < 4 in most cases.

   int hash = ((vtable_index << 2) ^ VtableStub::receiver_location()->value()) + vtable_index;

   return (is_vtable_stub ? ~hash : hash)  & mask;

 }

 VtableStub* VtableStubs::lookup(bool is_vtable_stub, int vtable_index) {

   MutexLocker ml(VtableStubs_lock);

   unsigned hash = VtableStubs::hash(is_vtable_stub, vtable_index);

   VtableStub* s = _table[hash];

   while( s && !s->matches(is_vtable_stub, vtable_index)) s = s->next();

   return s;

 }

 void VtableStubs::enter(bool is_vtable_stub, int vtable_index, VtableStub* s) {

   MutexLocker ml(VtableStubs_lock);

   assert(s->matches(is_vtable_stub, vtable_index), "bad vtable stub");

   unsigned int h = VtableStubs::hash(is_vtable_stub, vtable_index);

   // enter s at the beginning of the corresponding list

   s->set_next(_table[h]);

   _table[h] = s;

   _number_of_vtable_stubs++;

 }

 bool VtableStubs::is_entry_point(address pc) {

   MutexLocker ml(VtableStubs_lock);

   VtableStub* stub = (VtableStub*)(pc - VtableStub::entry_offset());

   uint hash = VtableStubs::hash(stub->is_vtable_stub(), stub->index());

   VtableStub* s;

   for (s = _table[hash]; s != NULL && s != stub; s = s->next()) {}

   return s == stub;

 }

 bool VtableStubs::contains(address pc) {

   // simple solution for now - we may want to use

   // a faster way if this function is called often

   return stub_containing(pc) != NULL;

 }

 VtableStub* VtableStubs::stub_containing(address pc) {

   // Note: No locking needed since any change to the data structure

   //       happens with an atomic store into it (we don't care about

   //       consistency with the _number_of_vtable_stubs counter).

   for (int i = 0; i < N; i++) {

     for (VtableStub* s = _table[i]; s != NULL; s = s->next()) {

       if (s->contains(pc)) return s;

     }

   }

   return NULL;

 }

 void vtableStubs_init() {

   VtableStubs::initialize();

 }

 //-----------------------------------------------------------------------------------------------------

 // Non-product code

 #ifndef PRODUCT

 extern "C" void bad_compiled_vtable_index(JavaThread* thread, oop receiver, int index) {

   ResourceMark rm;

   HandleMark hm;

   klassOop klass = receiver->klass();

   instanceKlass* ik = instanceKlass::cast(klass);

   klassVtable* vt = ik->vtable();

   klass->print();

   fatal(err_msg("bad compiled vtable dispatch: receiver " INTPTR_FORMAT ", "

                 "index %d (vtable length %d)",

                 (address)receiver, index, vt->length()));

 }

 #endif // Product