view src/share/vm/runtime/stubCodeGenerator.cpp @ 9126:bc26f978b0ce

HotSpotResolvedObjectType: implement hasFinalizeSubclass() correctly don't use the (wrong) cached value, but ask the runtime on each request. Fixes regression on xml.* benchmarks @ specjvm2008. The problem was: After the constructor of Object was deoptimized due to an assumption violation, it was recompiled again after some time. However, on recompilation, the value of hasFinalizeSubclass for the class was not updated and it was compiled again with a, now wrong, assumption, which then triggers deoptimization again. This was repeated until it hit the recompilation limit (defined by PerMethodRecompilationCutoff), and therefore only executed by the interpreter from now on, causing the performance regression.
author Bernhard Urban <bernhard.urban@jku.at>
date Mon, 15 Apr 2013 19:54:58 +0200
parents a5de0cc2f91c
children de6a9e811145
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/*
 * Copyright (c) 1997, 2011, 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 "precompiled.hpp"
#include "asm/macroAssembler.hpp"
#include "asm/macroAssembler.inline.hpp"
#include "code/codeCache.hpp"
#include "compiler/disassembler.hpp"
#include "oops/oop.inline.hpp"
#include "prims/forte.hpp"
#include "runtime/stubCodeGenerator.hpp"


// Implementation of StubCodeDesc

StubCodeDesc* StubCodeDesc::_list = NULL;
int           StubCodeDesc::_count = 0;


StubCodeDesc* StubCodeDesc::desc_for(address pc) {
  StubCodeDesc* p = _list;
  while (p != NULL && !p->contains(pc)) p = p->_next;
  // p == NULL || p->contains(pc)
  return p;
}


StubCodeDesc* StubCodeDesc::desc_for_index(int index) {
  StubCodeDesc* p = _list;
  while (p != NULL && p->index() != index) p = p->_next;
  return p;
}


const char* StubCodeDesc::name_for(address pc) {
  StubCodeDesc* p = desc_for(pc);
  return p == NULL ? NULL : p->name();
}


void StubCodeDesc::print_on(outputStream* st) const {
  st->print(group());
  st->print("::");
  st->print(name());
  st->print(" [" INTPTR_FORMAT ", " INTPTR_FORMAT "[ (%d bytes)", begin(), end(), size_in_bytes());
}

// Implementation of StubCodeGenerator

StubCodeGenerator::StubCodeGenerator(CodeBuffer* code, bool print_code) {
  _masm = new MacroAssembler(code);
  _first_stub = _last_stub = NULL;
  _print_code = print_code;
}

extern "C" {
  static int compare_cdesc(const void* void_a, const void* void_b) {
    int ai = (*((StubCodeDesc**) void_a))->index();
    int bi = (*((StubCodeDesc**) void_b))->index();
    return ai - bi;
  }
}

StubCodeGenerator::~StubCodeGenerator() {
  if (PrintStubCode || _print_code) {
    CodeBuffer* cbuf = _masm->code();
    CodeBlob*   blob = CodeCache::find_blob_unsafe(cbuf->insts()->start());
    if (blob != NULL) {
      blob->set_strings(cbuf->strings());
    }
    bool saw_first = false;
    StubCodeDesc* toprint[1000];
    int toprint_len = 0;
    for (StubCodeDesc* cdesc = _last_stub; cdesc != NULL; cdesc = cdesc->_next) {
      toprint[toprint_len++] = cdesc;
      if (cdesc == _first_stub) { saw_first = true; break; }
    }
    assert(saw_first, "must get both first & last");
    // Print in reverse order:
    qsort(toprint, toprint_len, sizeof(toprint[0]), compare_cdesc);
    for (int i = 0; i < toprint_len; i++) {
      StubCodeDesc* cdesc = toprint[i];
      cdesc->print();
      tty->cr();
      Disassembler::decode(cdesc->begin(), cdesc->end());
      tty->cr();
    }
  }
}


void StubCodeGenerator::stub_prolog(StubCodeDesc* cdesc) {
  // default implementation - do nothing
}


void StubCodeGenerator::stub_epilog(StubCodeDesc* cdesc) {
  // default implementation - record the cdesc
  if (_first_stub == NULL)  _first_stub = cdesc;
  _last_stub = cdesc;
}


// Implementation of CodeMark

StubCodeMark::StubCodeMark(StubCodeGenerator* cgen, const char* group, const char* name) {
  _cgen  = cgen;
  _cdesc = new StubCodeDesc(group, name, _cgen->assembler()->pc());
  _cgen->stub_prolog(_cdesc);
  // define the stub's beginning (= entry point) to be after the prolog:
  _cdesc->set_begin(_cgen->assembler()->pc());
}

StubCodeMark::~StubCodeMark() {
  _cgen->assembler()->flush();
  _cdesc->set_end(_cgen->assembler()->pc());
  assert(StubCodeDesc::_list == _cdesc, "expected order on list");
  _cgen->stub_epilog(_cdesc);
  Forte::register_stub(_cdesc->name(), _cdesc->begin(), _cdesc->end());

  if (JvmtiExport::should_post_dynamic_code_generated()) {
    JvmtiExport::post_dynamic_code_generated(_cdesc->name(), _cdesc->begin(), _cdesc->end());
  }
}