/*

 * 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.

 *

 */

class VM_Version : public Abstract_VM_Version {

public:

  // cpuid result register layouts.  These are all unions of a uint32_t

  // (in case anyone wants access to the register as a whole) and a bitfield.

  union StdCpuid1Eax {

    uint32_t value;

    struct {

      uint32_t stepping   : 4,

               model      : 4,

               family     : 4,

               proc_type  : 2,

                          : 2,

               ext_model  : 4,

               ext_family : 8,

                          : 4;

    } bits;

  };

  union StdCpuid1Ebx { // example, unused

    uint32_t value;

    struct {

      uint32_t brand_id         : 8,

               clflush_size     : 8,

               threads_per_cpu  : 8,

               apic_id          : 8;

    } bits;

  };

  union StdCpuid1Ecx {

    uint32_t value;

    struct {

      uint32_t sse3     : 1,

                        : 2,

               monitor  : 1,

                        : 1,

               vmx      : 1,

                        : 1,

               est      : 1,

                        : 1,

               ssse3    : 1,

               cid      : 1,

                        : 2,

               cmpxchg16: 1,

                        : 4,

               dca      : 1,

               sse4_1   : 1,

               sse4_2   : 1,

                        : 2,

               popcnt   : 1,

                        : 8;

    } bits;

  };

  union StdCpuid1Edx {

    uint32_t value;

    struct {

      uint32_t          : 4,

               tsc      : 1,

                        : 3,

               cmpxchg8 : 1,

                        : 6,

               cmov     : 1,

                        : 7,

               mmx      : 1,

               fxsr     : 1,

               sse      : 1,

               sse2     : 1,

                        : 1,

               ht       : 1,

                        : 3;

    } bits;

  };

  union DcpCpuid4Eax {

    uint32_t value;

    struct {

      uint32_t cache_type    : 5,

                             : 21,

               cores_per_cpu : 6;

    } bits;

  };

  union DcpCpuid4Ebx {

    uint32_t value;

    struct {

      uint32_t L1_line_size  : 12,

               partitions    : 10,

               associativity : 10;

    } bits;

  };

  union ExtCpuid1Ecx {

    uint32_t value;

    struct {

      uint32_t LahfSahf     : 1,

               CmpLegacy    : 1,

                            : 4,

               lzcnt        : 1,

               sse4a        : 1,

               misalignsse  : 1,

               prefetchw    : 1,

                            : 22;

    } bits;

  };

  union ExtCpuid1Edx {

    uint32_t value;

    struct {

      uint32_t           : 22,

               mmx_amd   : 1,

               mmx       : 1,

               fxsr      : 1,

                         : 4,

               long_mode : 1,

               tdnow2    : 1,

               tdnow     : 1;

    } bits;

  };

  union ExtCpuid5Ex {

    uint32_t value;

    struct {

      uint32_t L1_line_size : 8,

               L1_tag_lines : 8,

               L1_assoc     : 8,

               L1_size      : 8;

    } bits;

  };

  union ExtCpuid8Ecx {

    uint32_t value;

    struct {

      uint32_t cores_per_cpu : 8,

                             : 24;

    } bits;

  };

protected:

   static int _cpu;

   static int _model;

   static int _stepping;

   static int _cpuFeatures;     // features returned by the "cpuid" instruction

                                // 0 if this instruction is not available

   static const char* _features_str;

   enum {

     CPU_CX8    = (1 << 0), // next bits are from cpuid 1 (EDX)

     CPU_CMOV   = (1 << 1),

     CPU_FXSR   = (1 << 2),

     CPU_HT     = (1 << 3),

     CPU_MMX    = (1 << 4),

     CPU_3DNOW  = (1 << 5), // 3DNow comes from cpuid 0x80000001 (EDX)

     CPU_SSE    = (1 << 6),

     CPU_SSE2   = (1 << 7),

     CPU_SSE3   = (1 << 8), // SSE3 comes from cpuid 1 (ECX)

     CPU_SSSE3  = (1 << 9),

     CPU_SSE4A  = (1 << 10),

     CPU_SSE4_1 = (1 << 11),

     CPU_SSE4_2 = (1 << 12),

     CPU_POPCNT = (1 << 13),

     CPU_LZCNT  = (1 << 14)

   } cpuFeatureFlags;

  // cpuid information block.  All info derived from executing cpuid with

  // various function numbers is stored here.  Intel and AMD info is

  // merged in this block: accessor methods disentangle it.

  //

  // The info block is laid out in subblocks of 4 dwords corresponding to

  // eax, ebx, ecx and edx, whether or not they contain anything useful.

  struct CpuidInfo {

    // cpuid function 0

    uint32_t std_max_function;

    uint32_t std_vendor_name_0;

    uint32_t std_vendor_name_1;

    uint32_t std_vendor_name_2;

    // cpuid function 1

    StdCpuid1Eax std_cpuid1_eax;

    StdCpuid1Ebx std_cpuid1_ebx;

    StdCpuid1Ecx std_cpuid1_ecx;

    StdCpuid1Edx std_cpuid1_edx;

    // cpuid function 4 (deterministic cache parameters)

    DcpCpuid4Eax dcp_cpuid4_eax;

    DcpCpuid4Ebx dcp_cpuid4_ebx;

    uint32_t     dcp_cpuid4_ecx; // unused currently

    uint32_t     dcp_cpuid4_edx; // unused currently

    // cpuid function 0x80000000 // example, unused

    uint32_t ext_max_function;

    uint32_t ext_vendor_name_0;

    uint32_t ext_vendor_name_1;

    uint32_t ext_vendor_name_2;

    // cpuid function 0x80000001

    uint32_t     ext_cpuid1_eax; // reserved

    uint32_t     ext_cpuid1_ebx; // reserved

    ExtCpuid1Ecx ext_cpuid1_ecx;

    ExtCpuid1Edx ext_cpuid1_edx;

    // cpuid functions 0x80000002 thru 0x80000004: example, unused

    uint32_t proc_name_0, proc_name_1, proc_name_2, proc_name_3;

    uint32_t proc_name_4, proc_name_5, proc_name_6, proc_name_7;

    uint32_t proc_name_8, proc_name_9, proc_name_10,proc_name_11;

    // cpuid function 0x80000005 //AMD L1, Intel reserved

    uint32_t     ext_cpuid5_eax; // unused currently

    uint32_t     ext_cpuid5_ebx; // reserved

    ExtCpuid5Ex  ext_cpuid5_ecx; // L1 data cache info (AMD)

    ExtCpuid5Ex  ext_cpuid5_edx; // L1 instruction cache info (AMD)

    // cpuid function 0x80000008

    uint32_t     ext_cpuid8_eax; // unused currently

    uint32_t     ext_cpuid8_ebx; // reserved

    ExtCpuid8Ecx ext_cpuid8_ecx;

    uint32_t     ext_cpuid8_edx; // reserved

  };

  // The actual cpuid info block

  static CpuidInfo _cpuid_info;

  // Extractors and predicates

  static uint32_t extended_cpu_family() {

    uint32_t result = _cpuid_info.std_cpuid1_eax.bits.family;

    result += _cpuid_info.std_cpuid1_eax.bits.ext_family;

    return result;

  }

  static uint32_t extended_cpu_model() {

    uint32_t result = _cpuid_info.std_cpuid1_eax.bits.model;

    result |= _cpuid_info.std_cpuid1_eax.bits.ext_model << 4;

    return result;

  }

  static uint32_t cpu_stepping() {

    uint32_t result = _cpuid_info.std_cpuid1_eax.bits.stepping;

    return result;

  }

  static uint logical_processor_count() {

    uint result = threads_per_core();

    return result;

  }

  static uint32_t feature_flags() {

    uint32_t result = 0;

    if (_cpuid_info.std_cpuid1_edx.bits.cmpxchg8 != 0)

      result |= CPU_CX8;

    if (_cpuid_info.std_cpuid1_edx.bits.cmov != 0)

      result |= CPU_CMOV;

    if (_cpuid_info.std_cpuid1_edx.bits.fxsr != 0 || is_amd() &&

        _cpuid_info.ext_cpuid1_edx.bits.fxsr != 0)

      result |= CPU_FXSR;

    // HT flag is set for multi-core processors also.

    if (threads_per_core() > 1)

      result |= CPU_HT;

    if (_cpuid_info.std_cpuid1_edx.bits.mmx != 0 || is_amd() &&

        _cpuid_info.ext_cpuid1_edx.bits.mmx != 0)

      result |= CPU_MMX;

    if (_cpuid_info.std_cpuid1_edx.bits.sse != 0)

      result |= CPU_SSE;

    if (_cpuid_info.std_cpuid1_edx.bits.sse2 != 0)

      result |= CPU_SSE2;

    if (_cpuid_info.std_cpuid1_ecx.bits.sse3 != 0)

      result |= CPU_SSE3;

    if (_cpuid_info.std_cpuid1_ecx.bits.ssse3 != 0)

      result |= CPU_SSSE3;

    if (_cpuid_info.std_cpuid1_ecx.bits.sse4_1 != 0)

      result |= CPU_SSE4_1;

    if (_cpuid_info.std_cpuid1_ecx.bits.sse4_2 != 0)

      result |= CPU_SSE4_2;

    if (_cpuid_info.std_cpuid1_ecx.bits.popcnt != 0)

      result |= CPU_POPCNT;

    // AMD features.

    if (is_amd()) {

      if (_cpuid_info.ext_cpuid1_edx.bits.tdnow != 0)

        result |= CPU_3DNOW;

      if (_cpuid_info.ext_cpuid1_ecx.bits.lzcnt != 0)

        result |= CPU_LZCNT;

      if (_cpuid_info.ext_cpuid1_ecx.bits.sse4a != 0)

        result |= CPU_SSE4A;

    }

    return result;

  }

  static void get_processor_features();

public:

  // Offsets for cpuid asm stub

  static ByteSize std_cpuid0_offset() { return byte_offset_of(CpuidInfo, std_max_function); }

  static ByteSize std_cpuid1_offset() { return byte_offset_of(CpuidInfo, std_cpuid1_eax); }

  static ByteSize dcp_cpuid4_offset() { return byte_offset_of(CpuidInfo, dcp_cpuid4_eax); }

  static ByteSize ext_cpuid1_offset() { return byte_offset_of(CpuidInfo, ext_cpuid1_eax); }

  static ByteSize ext_cpuid5_offset() { return byte_offset_of(CpuidInfo, ext_cpuid5_eax); }

  static ByteSize ext_cpuid8_offset() { return byte_offset_of(CpuidInfo, ext_cpuid8_eax); }

  // Initialization

  static void initialize();

  // Asserts

  static void assert_is_initialized() {

    assert(_cpuid_info.std_cpuid1_eax.bits.family != 0, "VM_Version not initialized");

  }

  //

  // Processor family:

  //       3   -  386

  //       4   -  486

  //       5   -  Pentium

  //       6   -  PentiumPro, Pentium II, Celeron, Xeon, Pentium III, Athlon,

  //              Pentium M, Core Solo, Core Duo, Core2 Duo

  //    family 6 model:   9,        13,       14,        15

  //    0x0f   -  Pentium 4, Opteron

  //

  // Note: The cpu family should be used to select between

  //       instruction sequences which are valid on all Intel

  //       processors.  Use the feature test functions below to

  //       determine whether a particular instruction is supported.

  //

  static int  cpu_family()        { return _cpu;}

  static bool is_P6()             { return cpu_family() >= 6; }

  static bool is_amd()            { assert_is_initialized(); return _cpuid_info.std_vendor_name_0 == 0x68747541; } // 'htuA'

  static bool is_intel()          { assert_is_initialized(); return _cpuid_info.std_vendor_name_0 == 0x756e6547; } // 'uneG'

  static uint cores_per_cpu()  {

    uint result = 1;

    if (is_intel()) {

    } else if (is_amd()) {

      result = (_cpuid_info.ext_cpuid8_ecx.bits.cores_per_cpu + 1);

    }

    return result;

  }

  static uint threads_per_core()  {

    uint result = 1;

      result = _cpuid_info.std_cpuid1_ebx.bits.threads_per_cpu /

               cores_per_cpu();

    }

    return result;

  }

  static intx L1_data_cache_line_size()  {

    intx result = 0;

    if (is_intel()) {

      result = (_cpuid_info.dcp_cpuid4_ebx.bits.L1_line_size + 1);

    } else if (is_amd()) {

      result = _cpuid_info.ext_cpuid5_ecx.bits.L1_line_size;

    }

    if (result < 32) // not defined ?

      result = 32;   // 32 bytes by default on x86 and other x64

    return result;

  }

  //

  // Feature identification

  //

  static bool supports_cpuid()    { return _cpuFeatures  != 0; }

  static bool supports_cmpxchg8() { return (_cpuFeatures & CPU_CX8) != 0; }

  static bool supports_cmov()     { return (_cpuFeatures & CPU_CMOV) != 0; }

  static bool supports_fxsr()     { return (_cpuFeatures & CPU_FXSR) != 0; }

  static bool supports_ht()       { return (_cpuFeatures & CPU_HT) != 0; }

  static bool supports_mmx()      { return (_cpuFeatures & CPU_MMX) != 0; }

  static bool supports_sse()      { return (_cpuFeatures & CPU_SSE) != 0; }

  static bool supports_sse2()     { return (_cpuFeatures & CPU_SSE2) != 0; }

  static bool supports_sse3()     { return (_cpuFeatures & CPU_SSE3) != 0; }

  static bool supports_ssse3()    { return (_cpuFeatures & CPU_SSSE3)!= 0; }

  static bool supports_sse4_1()   { return (_cpuFeatures & CPU_SSE4_1) != 0; }

  static bool supports_sse4_2()   { return (_cpuFeatures & CPU_SSE4_2) != 0; }

  static bool supports_popcnt()   { return (_cpuFeatures & CPU_POPCNT) != 0; }

  //

  // AMD features

  //

  static bool supports_3dnow()    { return (_cpuFeatures & CPU_3DNOW) != 0; }

  static bool supports_mmx_ext()  { return is_amd() && _cpuid_info.ext_cpuid1_edx.bits.mmx_amd != 0; }

  static bool supports_3dnow2()   { return is_amd() && _cpuid_info.ext_cpuid1_edx.bits.tdnow2 != 0; }

  static bool supports_lzcnt()    { return (_cpuFeatures & CPU_LZCNT) != 0; }

  static bool supports_sse4a()    { return (_cpuFeatures & CPU_SSE4A) != 0; }

  static bool supports_compare_and_exchange() { return true; }

  static const char* cpu_features()           { return _features_str; }

  static intx allocate_prefetch_distance() {

    // This method should be called before allocate_prefetch_style().

    //

    // Hardware prefetching (distance/size in bytes):

    // Pentium 3 -  64 /  32

    // Pentium 4 - 256 / 128

    // Athlon    -  64 /  32 ????

    // Opteron   - 128 /  64 only when 2 sequential cache lines accessed

    // Core      - 128 /  64

    //

    // Software prefetching (distance in bytes / instruction with best score):

    // Pentium 3 - 128 / prefetchnta

    // Pentium 4 - 512 / prefetchnta

    // Athlon    - 128 / prefetchnta

    // Opteron   - 256 / prefetchnta

    // Core      - 256 / prefetchnta

    // It will be used only when AllocatePrefetchStyle > 0

    intx count = AllocatePrefetchDistance;

    if (count < 0) {   // default ?

      if (is_amd()) {  // AMD

        if (supports_sse2())

          count = 256; // Opteron

        else

          count = 128; // Athlon

      } else {         // Intel

        if (supports_sse2())

          if (cpu_family() == 6) {

            count = 256; // Pentium M, Core, Core2

          } else {

            count = 512; // Pentium 4

          }

        else

          count = 128; // Pentium 3 (and all other old CPUs)

      }

    }

    return count;

  }

  static intx allocate_prefetch_style() {

    assert(AllocatePrefetchStyle >= 0, "AllocatePrefetchStyle should be positive");

    // Return 0 if AllocatePrefetchDistance was not defined.

    return AllocatePrefetchDistance > 0 ? AllocatePrefetchStyle : 0;

  }

  // Prefetch interval for gc copy/scan == 9 dcache lines.  Derived from

  // 50-warehouse specjbb runs on a 2-way 1.8ghz opteron using a 4gb heap.

  // Tested intervals from 128 to 2048 in increments of 64 == one cache line.

  // 256 bytes (4 dcache lines) was the nearest runner-up to 576.

  // gc copy/scan is disabled if prefetchw isn't supported, because

  // Prefetch::write emits an inlined prefetchw on Linux.

  // Do not use the 3dnow prefetchw instruction.  It isn't supported on em64t.

  // The used prefetcht0 instruction works for both amd64 and em64t.

  static intx prefetch_copy_interval_in_bytes() {

    intx interval = PrefetchCopyIntervalInBytes;

    return interval >= 0 ? interval : 576;

  }

  static intx prefetch_scan_interval_in_bytes() {

    intx interval = PrefetchScanIntervalInBytes;

    return interval >= 0 ? interval : 576;

  }

  static intx prefetch_fields_ahead() {

    intx count = PrefetchFieldsAhead;

    return count >= 0 ? count : 1;

  }

};