8186777: Make Klass::_java_mirror an OopHandle
Summary: Add indirection for fetching mirror so that GC doesn't have to follow CLD::_klasses
Reviewed-by: hseigel, thartmann, eosterlund, stefank
Contributed-by: coleen.phillimore@oracle.com, rickard.backman@oracle.com
/*
* Copyright (c) 2016, Oracle and/or its affiliates. All rights reserved.
* Copyright (c) 2016 SAP SE. 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 CPU_S390_VM_GLOBALS_S390_HPP
#define CPU_S390_VM_GLOBALS_S390_HPP
#include "utilities/globalDefinitions.hpp"
#include "utilities/macros.hpp"
// Sets the default values for platform dependent flags used by the runtime system.
// (see globals.hpp)
// Sorted according to sparc.
// z/Architecture remembers branch targets, so don't share vtables.
define_pd_global(bool, ShareVtableStubs, false);
define_pd_global(bool, NeedsDeoptSuspend, false); // Only register window machines need this.
define_pd_global(bool, ImplicitNullChecks, true); // Generate code for implicit null checks.
define_pd_global(bool, TrapBasedNullChecks, true);
define_pd_global(bool, UncommonNullCast, true); // Uncommon-trap NULLs passed to check cast.
define_pd_global(uintx, CodeCacheSegmentSize, 256);
// This shall be at least 32 for proper branch target alignment.
// Ideally, this is 256 (cache line size). This keeps code end data
// on separate lines. But we reduced it to 64 since 256 increased
// code size significantly by padding nops between IVC and second UEP.
define_pd_global(intx, CodeEntryAlignment, 64);
define_pd_global(intx, OptoLoopAlignment, 2);
define_pd_global(intx, InlineFrequencyCount, 100);
define_pd_global(intx, InlineSmallCode, 2000);
#define DEFAULT_STACK_YELLOW_PAGES (2)
#define DEFAULT_STACK_RED_PAGES (1)
// Java_java_net_SocketOutputStream_socketWrite0() uses a 64k buffer on the
// stack. To pass stack overflow tests we need 20 shadow pages.
#define DEFAULT_STACK_SHADOW_PAGES (20 DEBUG_ONLY(+2))
#define DEFAULT_STACK_RESERVED_PAGES (1)
#define MIN_STACK_YELLOW_PAGES DEFAULT_STACK_YELLOW_PAGES
#define MIN_STACK_RED_PAGES DEFAULT_STACK_RED_PAGES
#define MIN_STACK_SHADOW_PAGES DEFAULT_STACK_SHADOW_PAGES
#define MIN_STACK_RESERVED_PAGES (0)
define_pd_global(intx, StackYellowPages, DEFAULT_STACK_YELLOW_PAGES);
define_pd_global(intx, StackRedPages, DEFAULT_STACK_RED_PAGES);
define_pd_global(intx, StackShadowPages, DEFAULT_STACK_SHADOW_PAGES);
define_pd_global(intx, StackReservedPages, DEFAULT_STACK_RESERVED_PAGES);
define_pd_global(bool, RewriteBytecodes, true);
define_pd_global(bool, RewriteFrequentPairs, true);
define_pd_global(bool, UseMembar, false);
define_pd_global(bool, PreserveFramePointer, false);
// GC Ergo Flags
define_pd_global(size_t, CMSYoungGenPerWorker, 16*M); // Default max size of CMS young gen, per GC worker thread.
define_pd_global(uintx, TypeProfileLevel, 111);
define_pd_global(bool, CompactStrings, true);
// 8146801 (Short Array Allocation): No performance work done here yet.
define_pd_global(intx, InitArrayShortSize, 1*BytesPerLong);
#define ARCH_FLAGS(develop, product, diagnostic, experimental, notproduct, range, constraint, writeable) \
\
/* Reoptimize code-sequences of calls at runtime, e.g. replace an */ \
/* indirect call by a direct call. */ \
product(bool, ReoptimizeCallSequences, true, \
"Reoptimize code-sequences of calls at runtime.") \
\
product(bool, UseByteReverseInstruction, true, \
"Use byte reverse instruction.") \
\
product(bool, ExpandLoadingBaseDecode, true, "Expand the assembler " \
"instruction required to load the base from DecodeN nodes during " \
"matching.") \
product(bool, ExpandLoadingBaseDecode_NN, true, "Expand the assembler " \
"instruction required to load the base from DecodeN_NN nodes " \
"during matching.") \
product(bool, ExpandLoadingBaseEncode, true, "Expand the assembler " \
"instruction required to load the base from EncodeP nodes during " \
"matching.") \
product(bool, ExpandLoadingBaseEncode_NN, true, "Expand the assembler " \
"instruction required to load the base from EncodeP_NN nodes " \
"during matching.") \
\
/* Seems to pay off with 2 pages already. */ \
product(size_t, MVCLEThreshold, +2*(4*K), \
"Threshold above which page-aligned MVCLE copy/init is used.") \
\
product(bool, PreferLAoverADD, false, \
"Use LA/LAY instructions over ADD instructions (z/Architecture).") \
\
develop(bool, ZapEmptyStackFields, false, "Write 0x0101... to empty stack" \
" fields. Use this to ease stack debugging.") \
\
product(bool, TraceTraps, false, "Trace all traps the signal handler" \
"handles.")
#endif // CPU_S390_VM_GLOBALS_S390_HPP