Mercurial > hg > truffle
view src/share/vm/oops/compiledICHolder.hpp @ 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 | da91efe96a93 |
children |
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/* * Copyright (c) 1998, 2012, 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. * */ #ifndef SHARE_VM_OOPS_COMPILEDICHOLDEROOP_HPP #define SHARE_VM_OOPS_COMPILEDICHOLDEROOP_HPP #include "oops/oop.hpp" // A CompiledICHolder* is a helper object for the inline cache implementation. // It holds an intermediate value (method+klass pair) used when converting from // compiled to an interpreted call. // // These are always allocated in the C heap and are freed during a // safepoint by the ICBuffer logic. It's unsafe to free them earlier // since they might be in use. // class CompiledICHolder : public CHeapObj<mtCompiler> { friend class VMStructs; private: static volatile int _live_count; // allocated static volatile int _live_not_claimed_count; // allocated but not yet in use so not // reachable by iterating over nmethods Method* _holder_method; Klass* _holder_klass; // to avoid name conflict with oopDesc::_klass CompiledICHolder* _next; public: // Constructor CompiledICHolder(Method* method, Klass* klass) : _holder_method(method), _holder_klass(klass) { #ifdef ASSERT Atomic::inc(&_live_count); Atomic::inc(&_live_not_claimed_count); #endif } ~CompiledICHolder() { #ifdef ASSERT assert(_live_count > 0, "underflow"); Atomic::dec(&_live_count); #endif } static int live_count() { return _live_count; } static int live_not_claimed_count() { return _live_not_claimed_count; } // accessors Method* holder_method() const { return _holder_method; } Klass* holder_klass() const { return _holder_klass; } void set_holder_method(Method* m) { _holder_method = m; } void set_holder_klass(Klass* k) { _holder_klass = k; } // interpreter support (offsets in bytes) static int holder_method_offset() { return offset_of(CompiledICHolder, _holder_method); } static int holder_klass_offset() { return offset_of(CompiledICHolder, _holder_klass); } CompiledICHolder* next() { return _next; } void set_next(CompiledICHolder* n) { _next = n; } // Verify void verify_on(outputStream* st); // Printing void print_on(outputStream* st) const; void print_value_on(outputStream* st) const; const char* internal_name() const { return "{compiledICHolder}"; } void claim() { #ifdef ASSERT Atomic::dec(&_live_not_claimed_count); #endif } }; #endif // SHARE_VM_OOPS_COMPILEDICHOLDEROOP_HPP