void VM_Version::initialize() {
  _features = determine_features();
  PrefetchCopyIntervalInBytes = prefetch_copy_interval_in_bytes();
  PrefetchScanIntervalInBytes = prefetch_scan_interval_in_bytes();
  PrefetchFieldsAhead         = prefetch_fields_ahead();

  assert(0 <= AllocatePrefetchInstr && AllocatePrefetchInstr <= 1, "invalid value");
  if( AllocatePrefetchInstr < 0 ) AllocatePrefetchInstr = 0;
  if( AllocatePrefetchInstr > 1 ) AllocatePrefetchInstr = 0;

  // Allocation prefetch settings
  intx cache_line_size = prefetch_data_size();
  if( cache_line_size > AllocatePrefetchStepSize )
    AllocatePrefetchStepSize = cache_line_size;

  assert(AllocatePrefetchLines > 0, "invalid value");
  if( AllocatePrefetchLines < 1 )     // set valid value in product VM
    AllocatePrefetchLines = 3;
  assert(AllocateInstancePrefetchLines > 0, "invalid value");
  if( AllocateInstancePrefetchLines < 1 ) // set valid value in product VM
    AllocateInstancePrefetchLines = 1;

  AllocatePrefetchDistance = allocate_prefetch_distance();
  AllocatePrefetchStyle    = allocate_prefetch_style();

  assert((AllocatePrefetchDistance % AllocatePrefetchStepSize) == 0 &&
         (AllocatePrefetchDistance > 0), "invalid value");
  if ((AllocatePrefetchDistance % AllocatePrefetchStepSize) != 0 ||
      (AllocatePrefetchDistance <= 0)) {
    AllocatePrefetchDistance = AllocatePrefetchStepSize;
  }

  if (AllocatePrefetchStyle == 3 && !has_blk_init()) {
    warning("BIS instructions are not available on this CPU");
    FLAG_SET_DEFAULT(AllocatePrefetchStyle, 1);
  }

  guarantee(VM_Version::has_v9(), "only SPARC v9 is supported");

  assert(ArraycopySrcPrefetchDistance < 4096, "invalid value");
  if (ArraycopySrcPrefetchDistance >= 4096)
    ArraycopySrcPrefetchDistance = 4064;
  assert(ArraycopyDstPrefetchDistance < 4096, "invalid value");
  if (ArraycopyDstPrefetchDistance >= 4096)
    ArraycopyDstPrefetchDistance = 4064;

  UseSSE = 0; // Only on x86 and x64

  _supports_cx8 = has_v9();
  _supports_atomic_getset4 = true; // swap instruction

  // There are Fujitsu Sparc64 CPUs which support blk_init as well so
  // we have to take this check out of the 'is_niagara()' block below.
  if (has_blk_init()) {
    // When using CMS or G1, we cannot use memset() in BOT updates
    // because the sun4v/CMT version in libc_psr uses BIS which
    // exposes "phantom zeros" to concurrent readers. See 6948537.
    if (FLAG_IS_DEFAULT(UseMemSetInBOT) && (UseConcMarkSweepGC || UseG1GC)) {
      FLAG_SET_DEFAULT(UseMemSetInBOT, false);
    }
    // Issue a stern warning if the user has explicitly set
    // UseMemSetInBOT (it is known to cause issues), but allow
    // use for experimentation and debugging.
    if (UseConcMarkSweepGC || UseG1GC) {
      if (UseMemSetInBOT) {
        assert(!FLAG_IS_DEFAULT(UseMemSetInBOT), "Error");
        warning("Experimental flag -XX:+UseMemSetInBOT is known to cause instability"
                " on sun4v; please understand that you are using at your own risk!");
      }
    }
  }

  if (is_niagara()) {
    // Indirect branch is the same cost as direct
    if (FLAG_IS_DEFAULT(UseInlineCaches)) {
      FLAG_SET_DEFAULT(UseInlineCaches, false);
    }
    // Align loops on a single instruction boundary.
    if (FLAG_IS_DEFAULT(OptoLoopAlignment)) {
      FLAG_SET_DEFAULT(OptoLoopAlignment, 4);
    }
#ifdef _LP64
    // 32-bit oops don't make sense for the 64-bit VM on sparc
    // since the 32-bit VM has the same registers and smaller objects.
    Universe::set_narrow_oop_shift(LogMinObjAlignmentInBytes);
    Universe::set_narrow_klass_shift(LogKlassAlignmentInBytes);
#endif // _LP64
#ifdef COMPILER2
    // Indirect branch is the same cost as direct
    if (FLAG_IS_DEFAULT(UseJumpTables)) {
      FLAG_SET_DEFAULT(UseJumpTables, true);
    }
    // Single-issue, so entry and loop tops are
    // aligned on a single instruction boundary
    if (FLAG_IS_DEFAULT(InteriorEntryAlignment)) {
      FLAG_SET_DEFAULT(InteriorEntryAlignment, 4);
    }
    if (is_niagara_plus()) {
      if (has_blk_init() && UseTLAB &&
          FLAG_IS_DEFAULT(AllocatePrefetchInstr)) {
        // Use BIS instruction for TLAB allocation prefetch.
        FLAG_SET_ERGO(intx, AllocatePrefetchInstr, 1);
        if (FLAG_IS_DEFAULT(AllocatePrefetchStyle)) {
          FLAG_SET_ERGO(intx, AllocatePrefetchStyle, 3);
        }
        if (FLAG_IS_DEFAULT(AllocatePrefetchDistance)) {
          // Use smaller prefetch distance with BIS
          FLAG_SET_DEFAULT(AllocatePrefetchDistance, 64);
        }
      }
      if (is_T4()) {
        // Double number of prefetched cache lines on T4
        // since L2 cache line size is smaller (32 bytes).
        if (FLAG_IS_DEFAULT(AllocatePrefetchLines)) {
          FLAG_SET_ERGO(intx, AllocatePrefetchLines, AllocatePrefetchLines*2);
        }
        if (FLAG_IS_DEFAULT(AllocateInstancePrefetchLines)) {
          FLAG_SET_ERGO(intx, AllocateInstancePrefetchLines, AllocateInstancePrefetchLines*2);
        }
      }
      if (AllocatePrefetchStyle != 3 && FLAG_IS_DEFAULT(AllocatePrefetchDistance)) {
        // Use different prefetch distance without BIS
        FLAG_SET_DEFAULT(AllocatePrefetchDistance, 256);
      }
      if (AllocatePrefetchInstr == 1) {
        // Need a space at the end of TLAB for BIS since it
        // will fault when accessing memory outside of heap.

        // +1 for rounding up to next cache line, +1 to be safe
        int lines = AllocatePrefetchLines + 2;
        int step_size = AllocatePrefetchStepSize;
        int distance = AllocatePrefetchDistance;
        _reserve_for_allocation_prefetch = (distance + step_size*lines)/(int)HeapWordSize;
      }
    }
#endif
  }

  // Use hardware population count instruction if available.
  if (has_hardware_popc()) {
    if (FLAG_IS_DEFAULT(UsePopCountInstruction)) {
      FLAG_SET_DEFAULT(UsePopCountInstruction, true);
    }
  } else if (UsePopCountInstruction) {
    warning("POPC instruction is not available on this CPU");
    FLAG_SET_DEFAULT(UsePopCountInstruction, false);
  }

  // T4 and newer Sparc cpus have new compare and branch instruction.
  if (has_cbcond()) {
    if (FLAG_IS_DEFAULT(UseCBCond)) {
      FLAG_SET_DEFAULT(UseCBCond, true);
    }
  } else if (UseCBCond) {
    warning("CBCOND instruction is not available on this CPU");
    FLAG_SET_DEFAULT(UseCBCond, false);
  }

  assert(BlockZeroingLowLimit > 0, "invalid value");
  if (has_block_zeroing()) {
    if (FLAG_IS_DEFAULT(UseBlockZeroing)) {
      FLAG_SET_DEFAULT(UseBlockZeroing, true);
    }
  } else if (UseBlockZeroing) {
    warning("BIS zeroing instructions are not available on this CPU");
    FLAG_SET_DEFAULT(UseBlockZeroing, false);
  }

  assert(BlockCopyLowLimit > 0, "invalid value");
  if (has_block_zeroing()) { // has_blk_init() && is_T4(): core's local L2 cache
    if (FLAG_IS_DEFAULT(UseBlockCopy)) {
      FLAG_SET_DEFAULT(UseBlockCopy, true);
    }
  } else if (UseBlockCopy) {
    warning("BIS instructions are not available or expensive on this CPU");
    FLAG_SET_DEFAULT(UseBlockCopy, false);
  }

#ifdef COMPILER2
  // T4 and newer Sparc cpus have fast RDPC.
  if (has_fast_rdpc() && FLAG_IS_DEFAULT(UseRDPCForConstantTableBase)) {
    FLAG_SET_DEFAULT(UseRDPCForConstantTableBase, true);
  }

  // Currently not supported anywhere.
  FLAG_SET_DEFAULT(UseFPUForSpilling, false);

  MaxVectorSize = 8;

  assert((InteriorEntryAlignment % relocInfo::addr_unit()) == 0, "alignment is not a multiple of NOP size");
#endif

  assert((CodeEntryAlignment % relocInfo::addr_unit()) == 0, "alignment is not a multiple of NOP size");
  assert((OptoLoopAlignment % relocInfo::addr_unit()) == 0, "alignment is not a multiple of NOP size");

  char buf[512];
  jio_snprintf(buf, sizeof(buf), "%s%s%s%s%s%s%s%s%s%s%s%s%s%s%s",
               (has_v9() ? ", v9" : (has_v8() ? ", v8" : "")),
               (has_hardware_popc() ? ", popc" : ""),
               (has_vis1() ? ", vis1" : ""),
               (has_vis2() ? ", vis2" : ""),
               (has_vis3() ? ", vis3" : ""),
               (has_blk_init() ? ", blk_init" : ""),
               (has_cbcond() ? ", cbcond" : ""),
               (has_aes() ? ", aes" : ""),
               (is_ultra3() ? ", ultra3" : ""),
               (is_sun4v() ? ", sun4v" : ""),
               (is_niagara_plus() ? ", niagara_plus" : (is_niagara() ? ", niagara" : "")),
               (is_sparc64() ? ", sparc64" : ""),
               (!has_hardware_mul32() ? ", no-mul32" : ""),
               (!has_hardware_div32() ? ", no-div32" : ""),
               (!has_hardware_fsmuld() ? ", no-fsmuld" : ""));

  // buf is started with ", " or is empty
  _features_str = strdup(strlen(buf) > 2 ? buf + 2 : buf);

  // UseVIS is set to the smallest of what hardware supports and what
  // the command line requires.  I.e., you cannot set UseVIS to 3 on
  // older UltraSparc which do not support it.
  if (UseVIS > 3) UseVIS=3;
  if (UseVIS < 0) UseVIS=0;
  if (!has_vis3()) // Drop to 2 if no VIS3 support
    UseVIS = MIN2((intx)2,UseVIS);
  if (!has_vis2()) // Drop to 1 if no VIS2 support
    UseVIS = MIN2((intx)1,UseVIS);
  if (!has_vis1()) // Drop to 0 if no VIS1 support
    UseVIS = 0;

  // T2 and above should have support for AES instructions
  if (has_aes()) {
    if (UseVIS > 0) { // AES intrinsics use FXOR instruction which is VIS1
      if (FLAG_IS_DEFAULT(UseAES)) {
        FLAG_SET_DEFAULT(UseAES, true);
      }
      if (FLAG_IS_DEFAULT(UseAESIntrinsics)) {
        FLAG_SET_DEFAULT(UseAESIntrinsics, true);
      }
      // we disable both the AES flags if either of them is disabled on the command line
      if (!UseAES || !UseAESIntrinsics) {
        FLAG_SET_DEFAULT(UseAES, false);
        FLAG_SET_DEFAULT(UseAESIntrinsics, false);
      }
    } else {
        if (UseAES || UseAESIntrinsics) {
          warning("SPARC AES intrinsics require VIS1 instruction support. Intrinsics will be disabled.");
          if (UseAES) {
            FLAG_SET_DEFAULT(UseAES, false);
          }
          if (UseAESIntrinsics) {
            FLAG_SET_DEFAULT(UseAESIntrinsics, false);
          }
        }
    }
  } else if (UseAES || UseAESIntrinsics) {
    warning("AES instructions are not available on this CPU");
    if (UseAES) {
      FLAG_SET_DEFAULT(UseAES, false);
    }
    if (UseAESIntrinsics) {
      FLAG_SET_DEFAULT(UseAESIntrinsics, false);
    }
  }

  if (FLAG_IS_DEFAULT(ContendedPaddingWidth) &&
    (cache_line_size > ContendedPaddingWidth))
    ContendedPaddingWidth = cache_line_size;

#ifndef PRODUCT
  if (PrintMiscellaneous && Verbose) {
    tty->print("Allocation");
    if (AllocatePrefetchStyle <= 0) {
      tty->print_cr(": no prefetching");
    } else {
      tty->print(" prefetching: ");
      if (AllocatePrefetchInstr == 0) {
          tty->print("PREFETCH");
      } else if (AllocatePrefetchInstr == 1) {
          tty->print("BIS");
      }
      if (AllocatePrefetchLines > 1) {
        tty->print_cr(" at distance %d, %d lines of %d bytes", AllocatePrefetchDistance, AllocatePrefetchLines, AllocatePrefetchStepSize);
      } else {
        tty->print_cr(" at distance %d, one line of %d bytes", AllocatePrefetchDistance, AllocatePrefetchStepSize);
      }
    }
    if (PrefetchCopyIntervalInBytes > 0) {
      tty->print_cr("PrefetchCopyIntervalInBytes %d", PrefetchCopyIntervalInBytes);
    }
    if (PrefetchScanIntervalInBytes > 0) {
      tty->print_cr("PrefetchScanIntervalInBytes %d", PrefetchScanIntervalInBytes);
    }
    if (PrefetchFieldsAhead > 0) {
      tty->print_cr("PrefetchFieldsAhead %d", PrefetchFieldsAhead);
    }
    if (ContendedPaddingWidth > 0) {
      tty->print_cr("ContendedPaddingWidth %d", ContendedPaddingWidth);
    }
  }
#endif // PRODUCT
}
 static bool v9_instructions_work() { return has_v9(); }
void VM_Version::initialize() {
  _features = determine_features();
  PrefetchCopyIntervalInBytes = prefetch_copy_interval_in_bytes();
  PrefetchScanIntervalInBytes = prefetch_scan_interval_in_bytes();
  PrefetchFieldsAhead         = prefetch_fields_ahead();

  // Allocation prefetch settings
  intx cache_line_size = L1_data_cache_line_size();
  if( cache_line_size > AllocatePrefetchStepSize )
    AllocatePrefetchStepSize = cache_line_size;
  if( FLAG_IS_DEFAULT(AllocatePrefetchLines) )
    AllocatePrefetchLines = 3; // Optimistic value
  assert( AllocatePrefetchLines > 0, "invalid value");
  if( AllocatePrefetchLines < 1 ) // set valid value in product VM
    AllocatePrefetchLines = 1; // Conservative value

  AllocatePrefetchDistance = allocate_prefetch_distance();
  AllocatePrefetchStyle    = allocate_prefetch_style();

  assert(AllocatePrefetchDistance % AllocatePrefetchStepSize == 0, "invalid value");

  UseSSE = 0; // Only on x86 and x64

  _supports_cx8               = has_v9();

  if (is_niagara1()) {
    // Indirect branch is the same cost as direct
    if (FLAG_IS_DEFAULT(UseInlineCaches)) {
      FLAG_SET_DEFAULT(UseInlineCaches, false);
    }
#ifdef _LP64
    // Single issue niagara1 is slower for CompressedOops
    // but niagaras after that it's fine.
    if (!is_niagara1_plus()) {
      if (FLAG_IS_DEFAULT(UseCompressedOops)) {
        FLAG_SET_ERGO(bool, UseCompressedOops, false);
      }
    }
    // 32-bit oops don't make sense for the 64-bit VM on sparc
    // since the 32-bit VM has the same registers and smaller objects.
    Universe::set_narrow_oop_shift(LogMinObjAlignmentInBytes);
#endif // _LP64
#ifdef COMPILER2
    // Indirect branch is the same cost as direct
    if (FLAG_IS_DEFAULT(UseJumpTables)) {
      FLAG_SET_DEFAULT(UseJumpTables, true);
    }
    // Single-issue, so entry and loop tops are
    // aligned on a single instruction boundary
    if (FLAG_IS_DEFAULT(InteriorEntryAlignment)) {
      FLAG_SET_DEFAULT(InteriorEntryAlignment, 4);
    }
    if (FLAG_IS_DEFAULT(OptoLoopAlignment)) {
      FLAG_SET_DEFAULT(OptoLoopAlignment, 4);
    }
    if (is_niagara1_plus() && FLAG_IS_DEFAULT(AllocatePrefetchDistance)) {
      // Use smaller prefetch distance on N2
      FLAG_SET_DEFAULT(AllocatePrefetchDistance, 256);
    }
#endif
  }

  // Use hardware population count instruction if available.
  if (has_hardware_popc()) {
    if (FLAG_IS_DEFAULT(UsePopCountInstruction)) {
      FLAG_SET_DEFAULT(UsePopCountInstruction, true);
    }
  }

  char buf[512];
  jio_snprintf(buf, sizeof(buf), "%s%s%s%s%s%s%s%s%s%s%s%s",
               (has_v8() ? ", has_v8" : ""),
               (has_v9() ? ", has_v9" : ""),
               (has_hardware_popc() ? ", popc" : ""),
               (has_vis1() ? ", has_vis1" : ""),
               (has_vis2() ? ", has_vis2" : ""),
               (is_ultra3() ? ", is_ultra3" : ""),
               (is_sun4v() ? ", is_sun4v" : ""),
               (is_niagara1() ? ", is_niagara1" : ""),
               (is_niagara1_plus() ? ", is_niagara1_plus" : ""),
               (!has_hardware_mul32() ? ", no-mul32" : ""),
               (!has_hardware_div32() ? ", no-div32" : ""),
               (!has_hardware_fsmuld() ? ", no-fsmuld" : ""));

  // buf is started with ", " or is empty
  _features_str = strdup(strlen(buf) > 2 ? buf + 2 : buf);

#ifndef PRODUCT
  if (PrintMiscellaneous && Verbose) {
    tty->print("Allocation: ");
    if (AllocatePrefetchStyle <= 0) {
      tty->print_cr("no prefetching");
    } else {
      if (AllocatePrefetchLines > 1) {
        tty->print_cr("PREFETCH %d, %d lines of size %d bytes", AllocatePrefetchDistance, AllocatePrefetchLines, AllocatePrefetchStepSize);
      } else {
        tty->print_cr("PREFETCH %d, one line", AllocatePrefetchDistance);
      }
    }
    if (PrefetchCopyIntervalInBytes > 0) {
      tty->print_cr("PrefetchCopyIntervalInBytes %d", PrefetchCopyIntervalInBytes);
    }
    if (PrefetchScanIntervalInBytes > 0) {
      tty->print_cr("PrefetchScanIntervalInBytes %d", PrefetchScanIntervalInBytes);
    }
    if (PrefetchFieldsAhead > 0) {
      tty->print_cr("PrefetchFieldsAhead %d", PrefetchFieldsAhead);
    }
  }
#endif // PRODUCT
}
 static intx prefetch_scan_interval_in_bytes() {
   intx interval = PrefetchScanIntervalInBytes;
   return interval >= 0 ? interval : (has_v9() ? 512 : 0);
 }
 // Legacy
 static bool v8_instructions_work() { return has_v8() && !has_v9(); }
 // Prefetch
 static intx prefetch_copy_interval_in_bytes() {
   intx interval = PrefetchCopyIntervalInBytes;
   return interval >= 0 ? interval : (has_v9() ? 512 : 0);
 }
 static bool has_fast_fxtof()          { return has_v9() && !is_ultra3(); }
 static bool supports_compare_and_exchange() 
                                       { return has_v9(); }
 static bool has_fast_fxtof()          { return is_niagara() || is_sparc64() || has_v9() && !is_ultra3(); }
Beispiel #10
0
void VM_Version::initialize() {
  _features = determine_features();
  PrefetchCopyIntervalInBytes = prefetch_copy_interval_in_bytes();
  PrefetchScanIntervalInBytes = prefetch_scan_interval_in_bytes();
  PrefetchFieldsAhead         = prefetch_fields_ahead();

  // Allocation prefetch settings
  intx cache_line_size = prefetch_data_size();
  if( cache_line_size > AllocatePrefetchStepSize )
    AllocatePrefetchStepSize = cache_line_size;

  assert(AllocatePrefetchLines > 0, "invalid value");
  if( AllocatePrefetchLines < 1 )     // set valid value in product VM
    AllocatePrefetchLines = 3;
  assert(AllocateInstancePrefetchLines > 0, "invalid value");
  if( AllocateInstancePrefetchLines < 1 ) // set valid value in product VM
    AllocateInstancePrefetchLines = 1;

  AllocatePrefetchDistance = allocate_prefetch_distance();
  AllocatePrefetchStyle    = allocate_prefetch_style();

  if (AllocatePrefetchStyle == 3 && !has_blk_init()) {
    warning("BIS instructions are not available on this CPU");
    FLAG_SET_DEFAULT(AllocatePrefetchStyle, 1);
  }

  guarantee(VM_Version::has_v9(), "only SPARC v9 is supported");

  UseSSE = 0; // Only on x86 and x64

  _supports_cx8 = has_v9();
  _supports_atomic_getset4 = true; // swap instruction

  if (is_niagara()) {
    // Indirect branch is the same cost as direct
    if (FLAG_IS_DEFAULT(UseInlineCaches)) {
      FLAG_SET_DEFAULT(UseInlineCaches, false);
    }
    // Align loops on a single instruction boundary.
    if (FLAG_IS_DEFAULT(OptoLoopAlignment)) {
      FLAG_SET_DEFAULT(OptoLoopAlignment, 4);
    }
#ifdef _LP64
    // 32-bit oops don't make sense for the 64-bit VM on sparc
    // since the 32-bit VM has the same registers and smaller objects.
    Universe::set_narrow_oop_shift(LogMinObjAlignmentInBytes);
    Universe::set_narrow_klass_shift(LogKlassAlignmentInBytes);
#endif // _LP64
#ifdef COMPILER2
    // Indirect branch is the same cost as direct
    if (FLAG_IS_DEFAULT(UseJumpTables)) {
      FLAG_SET_DEFAULT(UseJumpTables, true);
    }
    // Single-issue, so entry and loop tops are
    // aligned on a single instruction boundary
    if (FLAG_IS_DEFAULT(InteriorEntryAlignment)) {
      FLAG_SET_DEFAULT(InteriorEntryAlignment, 4);
    }
    if (is_niagara_plus()) {
      if (has_blk_init() && UseTLAB &&
          FLAG_IS_DEFAULT(AllocatePrefetchInstr)) {
        // Use BIS instruction for TLAB allocation prefetch.
        FLAG_SET_ERGO(intx, AllocatePrefetchInstr, 1);
        if (FLAG_IS_DEFAULT(AllocatePrefetchStyle)) {
          FLAG_SET_ERGO(intx, AllocatePrefetchStyle, 3);
        }
        if (FLAG_IS_DEFAULT(AllocatePrefetchDistance)) {
          // Use smaller prefetch distance with BIS
          FLAG_SET_DEFAULT(AllocatePrefetchDistance, 64);
        }
      }
      if (is_T4()) {
        // Double number of prefetched cache lines on T4
        // since L2 cache line size is smaller (32 bytes).
        if (FLAG_IS_DEFAULT(AllocatePrefetchLines)) {
          FLAG_SET_ERGO(intx, AllocatePrefetchLines, AllocatePrefetchLines*2);
        }
        if (FLAG_IS_DEFAULT(AllocateInstancePrefetchLines)) {
          FLAG_SET_ERGO(intx, AllocateInstancePrefetchLines, AllocateInstancePrefetchLines*2);
        }
      }
      if (AllocatePrefetchStyle != 3 && FLAG_IS_DEFAULT(AllocatePrefetchDistance)) {
        // Use different prefetch distance without BIS
        FLAG_SET_DEFAULT(AllocatePrefetchDistance, 256);
      }
      if (AllocatePrefetchInstr == 1) {
        // Need a space at the end of TLAB for BIS since it
        // will fault when accessing memory outside of heap.

        // +1 for rounding up to next cache line, +1 to be safe
        int lines = AllocatePrefetchLines + 2;
        int step_size = AllocatePrefetchStepSize;
        int distance = AllocatePrefetchDistance;
        _reserve_for_allocation_prefetch = (distance + step_size*lines)/(int)HeapWordSize;
      }
    }
#endif
  }

  // Use hardware population count instruction if available.
  if (has_hardware_popc()) {
    if (FLAG_IS_DEFAULT(UsePopCountInstruction)) {
      FLAG_SET_DEFAULT(UsePopCountInstruction, true);
    }
  } else if (UsePopCountInstruction) {
    warning("POPC instruction is not available on this CPU");
    FLAG_SET_DEFAULT(UsePopCountInstruction, false);
  }

  // T4 and newer Sparc cpus have new compare and branch instruction.
  if (has_cbcond()) {
    if (FLAG_IS_DEFAULT(UseCBCond)) {
      FLAG_SET_DEFAULT(UseCBCond, true);
    }
  } else if (UseCBCond) {
    warning("CBCOND instruction is not available on this CPU");
    FLAG_SET_DEFAULT(UseCBCond, false);
  }

  assert(BlockZeroingLowLimit > 0, "invalid value");
  if (has_block_zeroing() && cache_line_size > 0) {
    if (FLAG_IS_DEFAULT(UseBlockZeroing)) {
      FLAG_SET_DEFAULT(UseBlockZeroing, true);
    }
  } else if (UseBlockZeroing) {
    warning("BIS zeroing instructions are not available on this CPU");
    FLAG_SET_DEFAULT(UseBlockZeroing, false);
  }

  assert(BlockCopyLowLimit > 0, "invalid value");
  if (has_block_zeroing() && cache_line_size > 0) { // has_blk_init() && is_T4(): core's local L2 cache
    if (FLAG_IS_DEFAULT(UseBlockCopy)) {
      FLAG_SET_DEFAULT(UseBlockCopy, true);
    }
  } else if (UseBlockCopy) {
    warning("BIS instructions are not available or expensive on this CPU");
    FLAG_SET_DEFAULT(UseBlockCopy, false);
  }

#ifdef COMPILER2
  // T4 and newer Sparc cpus have fast RDPC.
  if (has_fast_rdpc() && FLAG_IS_DEFAULT(UseRDPCForConstantTableBase)) {
    FLAG_SET_DEFAULT(UseRDPCForConstantTableBase, true);
  }

  // Currently not supported anywhere.
  FLAG_SET_DEFAULT(UseFPUForSpilling, false);

  MaxVectorSize = 8;

  assert((InteriorEntryAlignment % relocInfo::addr_unit()) == 0, "alignment is not a multiple of NOP size");
#endif

  assert((CodeEntryAlignment % relocInfo::addr_unit()) == 0, "alignment is not a multiple of NOP size");
  assert((OptoLoopAlignment % relocInfo::addr_unit()) == 0, "alignment is not a multiple of NOP size");

  char buf[512];
  jio_snprintf(buf, sizeof(buf), "%s%s%s%s%s%s%s%s%s%s%s%s%s%s%s%s%s%s%s",
               (has_v9() ? ", v9" : (has_v8() ? ", v8" : "")),
               (has_hardware_popc() ? ", popc" : ""),
               (has_vis1() ? ", vis1" : ""),
               (has_vis2() ? ", vis2" : ""),
               (has_vis3() ? ", vis3" : ""),
               (has_blk_init() ? ", blk_init" : ""),
               (has_cbcond() ? ", cbcond" : ""),
               (has_aes() ? ", aes" : ""),
               (has_sha1() ? ", sha1" : ""),
               (has_sha256() ? ", sha256" : ""),
               (has_sha512() ? ", sha512" : ""),
               (has_crc32c() ? ", crc32c" : ""),
               (is_ultra3() ? ", ultra3" : ""),
               (is_sun4v() ? ", sun4v" : ""),
               (is_niagara_plus() ? ", niagara_plus" : (is_niagara() ? ", niagara" : "")),
               (is_sparc64() ? ", sparc64" : ""),
               (!has_hardware_mul32() ? ", no-mul32" : ""),
               (!has_hardware_div32() ? ", no-div32" : ""),
               (!has_hardware_fsmuld() ? ", no-fsmuld" : ""));

  // buf is started with ", " or is empty
  _features_str = os::strdup(strlen(buf) > 2 ? buf + 2 : buf);

  // UseVIS is set to the smallest of what hardware supports and what
  // the command line requires.  I.e., you cannot set UseVIS to 3 on
  // older UltraSparc which do not support it.
  if (UseVIS > 3) UseVIS=3;
  if (UseVIS < 0) UseVIS=0;
  if (!has_vis3()) // Drop to 2 if no VIS3 support
    UseVIS = MIN2((intx)2,UseVIS);
  if (!has_vis2()) // Drop to 1 if no VIS2 support
    UseVIS = MIN2((intx)1,UseVIS);
  if (!has_vis1()) // Drop to 0 if no VIS1 support
    UseVIS = 0;

  // SPARC T4 and above should have support for AES instructions
  if (has_aes()) {
    if (FLAG_IS_DEFAULT(UseAES)) {
      FLAG_SET_DEFAULT(UseAES, true);
    }
    if (!UseAES) {
      if (UseAESIntrinsics && !FLAG_IS_DEFAULT(UseAESIntrinsics)) {
        warning("AES intrinsics require UseAES flag to be enabled. Intrinsics will be disabled.");
      }
      FLAG_SET_DEFAULT(UseAESIntrinsics, false);
    } else {
      // The AES intrinsic stubs require AES instruction support (of course)
      // but also require VIS3 mode or higher for instructions it use.
      if (UseVIS > 2) {
        if (FLAG_IS_DEFAULT(UseAESIntrinsics)) {
          FLAG_SET_DEFAULT(UseAESIntrinsics, true);
        }
      } else {
        if (UseAESIntrinsics && !FLAG_IS_DEFAULT(UseAESIntrinsics)) {
          warning("SPARC AES intrinsics require VIS3 instructions. Intrinsics will be disabled.");
        }
        FLAG_SET_DEFAULT(UseAESIntrinsics, false);
      }
    }
  } else if (UseAES || UseAESIntrinsics) {
    if (UseAES && !FLAG_IS_DEFAULT(UseAES)) {
      warning("AES instructions are not available on this CPU");
      FLAG_SET_DEFAULT(UseAES, false);
    }
    if (UseAESIntrinsics && !FLAG_IS_DEFAULT(UseAESIntrinsics)) {
      warning("AES intrinsics are not available on this CPU");
      FLAG_SET_DEFAULT(UseAESIntrinsics, false);
    }
  }

  // GHASH/GCM intrinsics
  if (has_vis3() && (UseVIS > 2)) {
    if (FLAG_IS_DEFAULT(UseGHASHIntrinsics)) {
      UseGHASHIntrinsics = true;
    }
  } else if (UseGHASHIntrinsics) {
    if (!FLAG_IS_DEFAULT(UseGHASHIntrinsics))
      warning("GHASH intrinsics require VIS3 instruction support. Intrinsics will be disabled");
    FLAG_SET_DEFAULT(UseGHASHIntrinsics, false);
  }

  // SHA1, SHA256, and SHA512 instructions were added to SPARC T-series at different times
  if (has_sha1() || has_sha256() || has_sha512()) {
    if (UseVIS > 0) { // SHA intrinsics use VIS1 instructions
      if (FLAG_IS_DEFAULT(UseSHA)) {
        FLAG_SET_DEFAULT(UseSHA, true);
      }
    } else {
      if (UseSHA) {
        warning("SPARC SHA intrinsics require VIS1 instruction support. Intrinsics will be disabled.");
        FLAG_SET_DEFAULT(UseSHA, false);
      }
    }
  } else if (UseSHA) {
    warning("SHA instructions are not available on this CPU");
    FLAG_SET_DEFAULT(UseSHA, false);
  }

  if (UseSHA && has_sha1()) {
    if (FLAG_IS_DEFAULT(UseSHA1Intrinsics)) {
      FLAG_SET_DEFAULT(UseSHA1Intrinsics, true);
    }
  } else if (UseSHA1Intrinsics) {
    warning("Intrinsics for SHA-1 crypto hash functions not available on this CPU.");
    FLAG_SET_DEFAULT(UseSHA1Intrinsics, false);
  }

  if (UseSHA && has_sha256()) {
    if (FLAG_IS_DEFAULT(UseSHA256Intrinsics)) {
      FLAG_SET_DEFAULT(UseSHA256Intrinsics, true);
    }
  } else if (UseSHA256Intrinsics) {
    warning("Intrinsics for SHA-224 and SHA-256 crypto hash functions not available on this CPU.");
    FLAG_SET_DEFAULT(UseSHA256Intrinsics, false);
  }

  if (UseSHA && has_sha512()) {
    if (FLAG_IS_DEFAULT(UseSHA512Intrinsics)) {
      FLAG_SET_DEFAULT(UseSHA512Intrinsics, true);
    }
  } else if (UseSHA512Intrinsics) {
    warning("Intrinsics for SHA-384 and SHA-512 crypto hash functions not available on this CPU.");
    FLAG_SET_DEFAULT(UseSHA512Intrinsics, false);
  }

  if (!(UseSHA1Intrinsics || UseSHA256Intrinsics || UseSHA512Intrinsics)) {
    FLAG_SET_DEFAULT(UseSHA, false);
  }

  // SPARC T4 and above should have support for CRC32C instruction
  if (has_crc32c()) {
    if (UseVIS > 2) { // CRC32C intrinsics use VIS3 instructions
      if (FLAG_IS_DEFAULT(UseCRC32CIntrinsics)) {
        FLAG_SET_DEFAULT(UseCRC32CIntrinsics, true);
      }
    } else {
      if (UseCRC32CIntrinsics) {
        warning("SPARC CRC32C intrinsics require VIS3 instruction support. Intrinsics will be disabled.");
        FLAG_SET_DEFAULT(UseCRC32CIntrinsics, false);
      }
    }
  } else if (UseCRC32CIntrinsics) {
    warning("CRC32C instruction is not available on this CPU");
    FLAG_SET_DEFAULT(UseCRC32CIntrinsics, false);
  }

  if (UseVIS > 2) {
    if (FLAG_IS_DEFAULT(UseAdler32Intrinsics)) {
      FLAG_SET_DEFAULT(UseAdler32Intrinsics, true);
    }
  } else if (UseAdler32Intrinsics) {
    warning("SPARC Adler32 intrinsics require VIS3 instruction support. Intrinsics will be disabled.");
    FLAG_SET_DEFAULT(UseAdler32Intrinsics, false);
  }

  if (UseVIS > 2) {
    if (FLAG_IS_DEFAULT(UseCRC32Intrinsics)) {
      FLAG_SET_DEFAULT(UseCRC32Intrinsics, true);
    }
  } else if (UseCRC32Intrinsics) {
    warning("SPARC CRC32 intrinsics require VIS3 insructions support. Intriniscs will be disabled");
    FLAG_SET_DEFAULT(UseCRC32Intrinsics, false);
  }

  if (FLAG_IS_DEFAULT(ContendedPaddingWidth) &&
    (cache_line_size > ContendedPaddingWidth))
    ContendedPaddingWidth = cache_line_size;

  // This machine does not allow unaligned memory accesses
  if (UseUnalignedAccesses) {
    if (!FLAG_IS_DEFAULT(UseUnalignedAccesses))
      warning("Unaligned memory access is not available on this CPU");
    FLAG_SET_DEFAULT(UseUnalignedAccesses, false);
  }

  if (PrintMiscellaneous && Verbose) {
    tty->print_cr("L1 data cache line size: %u", L1_data_cache_line_size());
    tty->print_cr("L2 data cache line size: %u", L2_data_cache_line_size());
    tty->print("Allocation");
    if (AllocatePrefetchStyle <= 0) {
      tty->print_cr(": no prefetching");
    } else {
      tty->print(" prefetching: ");
      if (AllocatePrefetchInstr == 0) {
          tty->print("PREFETCH");
      } else if (AllocatePrefetchInstr == 1) {
          tty->print("BIS");
      }
      if (AllocatePrefetchLines > 1) {
        tty->print_cr(" at distance %d, %d lines of %d bytes", (int) AllocatePrefetchDistance, (int) AllocatePrefetchLines, (int) AllocatePrefetchStepSize);
      } else {
        tty->print_cr(" at distance %d, one line of %d bytes", (int) AllocatePrefetchDistance, (int) AllocatePrefetchStepSize);
      }
    }
    if (PrefetchCopyIntervalInBytes > 0) {
      tty->print_cr("PrefetchCopyIntervalInBytes %d", (int) PrefetchCopyIntervalInBytes);
    }
    if (PrefetchScanIntervalInBytes > 0) {
      tty->print_cr("PrefetchScanIntervalInBytes %d", (int) PrefetchScanIntervalInBytes);
    }
    if (PrefetchFieldsAhead > 0) {
      tty->print_cr("PrefetchFieldsAhead %d", (int) PrefetchFieldsAhead);
    }
    if (ContendedPaddingWidth > 0) {
      tty->print_cr("ContendedPaddingWidth %d", (int) ContendedPaddingWidth);
    }
  }
}