src/hotspot/cpu/aarch64/globals_aarch64.hpp

/*
 * Copyright (c) 2000, 2017, Oracle and/or its affiliates. All rights reserved.
 * Copyright (c) 2015, Red Hat Inc. All rights reserved.
 * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
 *
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 * 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
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#ifndef CPU_AARCH64_VM_GLOBALS_AARCH64_HPP
#define CPU_AARCH64_VM_GLOBALS_AARCH64_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)

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,  false);
define_pd_global(bool, UncommonNullCast,         true);  // Uncommon-trap NULLs past to check cast

define_pd_global(uintx, CodeCacheSegmentSize,    64 TIERED_ONLY(+64)); // Tiered compilation has large code-entry alignment.
define_pd_global(intx, CodeEntryAlignment,       64);
define_pd_global(intx, OptoLoopAlignment,        16);
define_pd_global(intx, InlineFrequencyCount,     100);

#define DEFAULT_STACK_YELLOW_PAGES (2)
#define DEFAULT_STACK_RED_PAGES (1)
// Java_java_net_SocketOutputStream_socketWrite0() uses a 64k buffer on the
// stack if compiled for unix and LP64. To pass stack overflow tests we need
// 20 shadow pages.
#define DEFAULT_STACK_SHADOW_PAGES (20 DEBUG_ONLY(+5))
#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,            true);

define_pd_global(bool, PreserveFramePointer, false);

// GC Ergo Flags
define_pd_global(uintx, CMSYoungGenPerWorker, 64*M);  // default max size of CMS young gen, per GC worker thread

define_pd_global(uintx, TypeProfileLevel, 111);

define_pd_global(bool, CompactStrings, true);

// Clear short arrays bigger than one word in an arch-specific way
define_pd_global(intx, InitArrayShortSize, BytesPerLong);

define_pd_global(bool, ThreadLocalHandshakes, true);

#if defined(COMPILER1) || defined(COMPILER2)
define_pd_global(intx, InlineSmallCode,          1000);
#endif

#define ARCH_FLAGS(develop, \
                   product, \
                   diagnostic, \
                   experimental, \
                   notproduct, \
                   range, \
                   constraint, \
                   writeable) \
                                                                        \
  product(bool, NearCpool, true,                                        \
         "constant pool is close to instructions")                      \
                                                                        \
  product(bool, UseBarriersForVolatile, false,                          \
          "Use memory barriers to implement volatile accesses")         \
  product(bool, UseNeon, false,                                         \
          "Use Neon for CRC32 computation")                             \
  product(bool, UseCRC32, false,                                        \
          "Use CRC32 instructions for CRC32 computation")               \
  product(bool, UseSIMDForMemoryOps, false,                             \
          "Use SIMD instructions in generated memory move code")        \
  product(bool, UseSIMDForArrayEquals, true,                            \
          "Use SIMD instructions in generated array equals code")       \
  product(bool, UseSimpleArrayEquals, false,                            \
          "Use simpliest and shortest implementation for array equals") \
  product(bool, AvoidUnalignedAccesses, false,                          \
          "Avoid generating unaligned memory accesses")                 \
  product(bool, UseLSE, false,                                          \
          "Use LSE instructions")                                       \
  product(bool, UseBlockZeroing, true,                                  \
          "Use DC ZVA for block zeroing")                               \
  product(intx, BlockZeroingLowLimit, 256,                              \
          "Minimum size in bytes when block zeroing will be used")      \
          range(1, max_jint)                                            \
  product(bool, TraceTraps, false, "Trace all traps the signal handler")\
  product(int, SoftwarePrefetchHintDistance, -1,                        \
          "Use prfm hint with specified distance in compiled code."     \
          "Value -1 means off.")                                        \
          range(-1, 4096)

#endif // CPU_AARCH64_VM_GLOBALS_AARCH64_HPP