text: /*
   * Copyright (c) 2000, 2021, 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 CPU_X86_GLOBALS_X86_HPP
  #define CPU_X86_GLOBALS_X86_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, ImplicitNullChecks,       true);  // Generate code for implicit null checks
  define_pd_global(bool, TrapBasedNullChecks,      false); // Not needed on x86.
  define_pd_global(bool, UncommonNullCast,         true);  // Uncommon-trap NULLs passed to check cast
  
  define_pd_global(uintx, CodeCacheSegmentSize,    64 COMPILER1_AND_COMPILER2_PRESENT(+64)); // Tiered compilation has large code-entry alignment.
  // See 4827828 for this change. There is no globals_core_i486.hpp. I can't
  // assign a different value for C2 without touching a number of files. Use
  // #ifdef to minimize the change as it's late in Mantis. -- FIXME.
  // c1 doesn't have this problem because the fix to 4858033 assures us
  // the the vep is aligned at CodeEntryAlignment whereas c2 only aligns
  // the uep and the vep doesn't get real alignment but just slops on by
  // only assured that the entry instruction meets the 5 byte size requirement.
  #if COMPILER2_OR_JVMCI
  define_pd_global(intx, CodeEntryAlignment,       32);
  #else
  define_pd_global(intx, CodeEntryAlignment,       16);
  #endif // COMPILER2_OR_JVMCI
  define_pd_global(intx, OptoLoopAlignment,        16);
  define_pd_global(intx, InlineFrequencyCount,     100);
  define_pd_global(intx, InlineSmallCode,          1000);
  
  #define DEFAULT_STACK_YELLOW_PAGES (NOT_WINDOWS(2) WINDOWS_ONLY(3))
  #define DEFAULT_STACK_RED_PAGES (1)
  #define DEFAULT_STACK_RESERVED_PAGES (NOT_WINDOWS(1) WINDOWS_ONLY(0))
  
  #define MIN_STACK_YELLOW_PAGES DEFAULT_STACK_YELLOW_PAGES
  #define MIN_STACK_RED_PAGES DEFAULT_STACK_RED_PAGES
  #define MIN_STACK_RESERVED_PAGES (0)
  
  #ifdef _LP64
  // 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 (NOT_WIN64(20) WIN64_ONLY(7) DEBUG_ONLY(+2))
  // For those clients that do not use write socket, we allow
  // the min range value to be below that of the default
  #define MIN_STACK_SHADOW_PAGES (NOT_WIN64(10) WIN64_ONLY(7) DEBUG_ONLY(+2))
  #else
  #define DEFAULT_STACK_SHADOW_PAGES (4 DEBUG_ONLY(+5))
  #define MIN_STACK_SHADOW_PAGES DEFAULT_STACK_SHADOW_PAGES
  #endif // _LP64
  
  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(uintx, TypeProfileLevel, 111);
  
  define_pd_global(bool, CompactStrings, true);
  
  define_pd_global(bool, PreserveFramePointer, false);
  
  define_pd_global(intx, InitArrayShortSize, 8*BytesPerLong);
  
  #define ARCH_FLAGS(develop,                                                 \
                     product,                                                 \
                     notproduct,                                              \
                     range,                                                   \
                     constraint)                                              \
                                                                              \
    develop(bool, IEEEPrecision, true,                                        \
            "Enables IEEE precision (for INTEL only)")                        \
                                                                              \
    product(bool, UseStoreImmI16, true,                                       \
            "Use store immediate 16-bits value instruction on x86")           \
                                                                              \
    product(intx, UseSSE, 99,                                                 \
            "Highest supported SSE instructions set on x86/x64")              \
            range(0, 99)                                                      \
                                                                              \
    product(intx, UseAVX, 3,                                                  \
            "Highest supported AVX instructions set on x86/x64")              \
            range(0, 99)                                                      \
                                                                              \
    product(bool, UseKNLSetting, false, DIAGNOSTIC,                           \
            "Control whether Knights platform setting should be used")        \
                                                                              \
    product(bool, UseCLMUL, false,                                            \
            "Control whether CLMUL instructions can be used on x86/x64")      \
                                                                              \
    product(bool, UseIncDec, true, DIAGNOSTIC,                                \
            "Use INC, DEC instructions on x86")                               \
                                                                              \
    product(bool, UseNewLongLShift, false,                                    \
            "Use optimized bitwise shift left")                               \
                                                                              \
    product(bool, UseAddressNop, false,                                       \
            "Use '0F 1F [addr]' NOP instructions on x86 cpus")                \
                                                                              \
    product(bool, UseXmmLoadAndClearUpper, true,                              \
            "Load low part of XMM register and clear upper part")             \
                                                                              \
    product(bool, UseXmmRegToRegMoveAll, false,                               \
            "Copy all XMM register bits when moving value between registers") \
                                                                              \
    product(bool, UseXmmI2D, false,                                           \
            "Use SSE2 CVTDQ2PD instruction to convert Integer to Double")     \
                                                                              \
    product(bool, UseXmmI2F, false,                                           \
            "Use SSE2 CVTDQ2PS instruction to convert Integer to Float")      \
                                                                              \
    product(bool, UseUnalignedLoadStores, false,                              \
            "Use SSE2 MOVDQU instruction for Arraycopy")                      \
                                                                              \
    product(bool, UseXMMForObjInit, false,                                    \
            "Use XMM/YMM MOVDQU instruction for Object Initialization")       \
                                                                              \
    product(bool, UseFastStosb, false,                                        \
            "Use fast-string operation for zeroing: rep stosb")               \
                                                                              \
    /* Use Restricted Transactional Memory for lock eliding */                \
    product(bool, UseRTMLocking, false,                                       \
            "Enable RTM lock eliding for inflated locks in compiled code")    \
                                                                              \
    product(bool, UseRTMForStackLocks, false, EXPERIMENTAL,                   \
            "Enable RTM lock eliding for stack locks in compiled code")       \
                                                                              \
    product(bool, UseRTMDeopt, false,                                         \
            "Perform deopt and recompilation based on RTM abort ratio")       \
                                                                              \
    product(int, RTMRetryCount, 5,                                            \
            "Number of RTM retries on lock abort or busy")                    \
            range(0, max_jint)                                                \
                                                                              \
    product(int, RTMSpinLoopCount, 100, EXPERIMENTAL,                         \
            "Spin count for lock to become free before RTM retry")            \
            range(0, max_jint)                                                \
                                                                              \
    product(int, RTMAbortThreshold, 1000, EXPERIMENTAL,                       \
            "Calculate abort ratio after this number of aborts")              \
            range(0, max_jint)                                                \
                                                                              \
    product(int, RTMLockingThreshold, 10000, EXPERIMENTAL,                    \
            "Lock count at which to do RTM lock eliding without "             \
            "abort ratio calculation")                                        \
            range(0, max_jint)                                                \
                                                                              \
    product(int, RTMAbortRatio, 50, EXPERIMENTAL,                             \
            "Lock abort ratio at which to stop use RTM lock eliding")         \
            range(0, 100) /* natural range */                                 \
                                                                              \
    product(int, RTMTotalCountIncrRate, 64, EXPERIMENTAL,                     \
            "Increment total RTM attempted lock count once every n times")    \
            range(1, max_jint)                                                \
            constraint(RTMTotalCountIncrRateConstraintFunc,AfterErgo)         \
                                                                              \
    product(intx, RTMLockingCalculationDelay, 0, EXPERIMENTAL,                \
            "Number of milliseconds to wait before start calculating aborts " \
            "for RTM locking")                                                \
                                                                              \
    product(bool, UseRTMXendForLockBusy, true, EXPERIMENTAL,                  \
            "Use RTM Xend instead of Xabort when lock busy")                  \
                                                                              \
    /* assembler */                                                           \
    product(bool, UseCountLeadingZerosInstruction, false,                     \
            "Use count leading zeros instruction")                            \
                                                                              \
    product(bool, UseCountTrailingZerosInstruction, false,                    \
            "Use count trailing zeros instruction")                           \
                                                                              \
    product(bool, UseSSE42Intrinsics, false,                                  \
            "SSE4.2 versions of intrinsics")                                  \
                                                                              \
    product(bool, UseBMI1Instructions, false,                                 \
            "Use BMI1 instructions")                                          \
                                                                              \
    product(bool, UseBMI2Instructions, false,                                 \
            "Use BMI2 instructions")                                          \
                                                                              \
    product(bool, UseLibmIntrinsic, true, DIAGNOSTIC,                         \
            "Use Libm Intrinsics")                                            \
                                                                              \
    /* Minimum array size in bytes to use AVX512 intrinsics */                \
    /* for copy, inflate and fill which don't bail out early based on any */  \
    /* condition. When this value is set to zero compare operations like */   \
    /* compare, vectorizedMismatch, compress can also use AVX512 intrinsics.*/\
    product(int, AVX3Threshold, 4096, DIAGNOSTIC,                             \
               "Minimum array size in bytes to use AVX512 intrinsics"         \
               "for copy, inflate and fill. When this value is set as zero"   \
               "compare operations can also use AVX512 intrinsics.")          \
               range(0, max_jint)                                             \
               constraint(AVX3ThresholdConstraintFunc,AfterErgo)              \
                                                                              \
    product(bool, IntelJccErratumMitigation, true, DIAGNOSTIC,                \
               "Turn off JVM mitigations related to Intel micro code "        \
               "mitigations for the Intel JCC erratum")
  
  // end of ARCH_FLAGS
  
  #endif // CPU_X86_GLOBALS_X86_HPP
  