static void verify_scaled_initial(size_t initial_heap_size) {
    MarkSweepPolicy msp;
    msp.initialize_all();

    size_t expected = msp.scale_by_NewRatio_aligned(initial_heap_size);
    assert(msp.initial_gen0_size() == expected, err_msg("%zu != %zu", msp.initial_gen0_size(), expected));
    assert(FLAG_IS_ERGO(NewSize) && NewSize == expected,
        err_msg("NewSize should have been set ergonomically to %zu, but was %zu", expected, NewSize));
  }
Flag::Error HeapBaseMinAddressConstraintFunc(size_t value, bool verbose) {
  // If an overflow happened in Arguments::set_heap_size(), MaxHeapSize will have too large a value.
  // Check for this by ensuring that MaxHeapSize plus the requested min base address still fit within max_uintx.
  if (UseCompressedOops && FLAG_IS_ERGO(MaxHeapSize) && (value > (max_uintx - MaxHeapSize))) {
    CommandLineError::print(verbose,
                            "HeapBaseMinAddress (" SIZE_FORMAT ") or MaxHeapSize (" SIZE_FORMAT ") is too large. "
                            "Sum of them must be less than or equal to maximum of size_t (" SIZE_FORMAT ")\n",
                            value, MaxHeapSize, max_uintx);
    return Flag::VIOLATES_CONSTRAINT;
  }

  return MaxSizeForHeapAlignment("HeapBaseMinAddress", value, verbose);
}
Exemplo n.º 3
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  static void verify_scaled_young_initial(size_t initial_heap_size) {
    MarkSweepPolicy msp;
    msp.initialize_all();

    if (InitialHeapSize > initial_heap_size) {
      // InitialHeapSize was adapted by msp.initialize_all, e.g. due to alignment
      // caused by 64K page size.
      initial_heap_size = InitialHeapSize;
    }

    size_t expected = msp.scale_by_NewRatio_aligned(initial_heap_size);
    assert(msp.initial_young_size() == expected, "%zu != %zu", msp.initial_young_size(), expected);
    assert(FLAG_IS_ERGO(NewSize) && NewSize == expected,
        "NewSize should have been set ergonomically to %zu, but was %zu", expected, NewSize);
  }
// Values set on the command line win over any ergonomically
// set command line parameters.
// Ergonomic choice of parameters are done before this
// method is called.  Values for command line parameters such as NewSize
// and MaxNewSize feed those ergonomic choices into this method.
// This method makes the final generation sizings consistent with
// themselves and with overall heap sizings.
// In the absence of explicitly set command line flags, policies
// such as the use of NewRatio are used to size the generation.
void GenCollectorPolicy::initialize_size_info() {
  CollectorPolicy::initialize_size_info();

  // _space_alignment is used for alignment within a generation.
  // There is additional alignment done down stream for some
  // collectors that sometimes causes unwanted rounding up of
  // generations sizes.

  // Determine maximum size of gen0

  size_t max_new_size = 0;
  if (!FLAG_IS_DEFAULT(MaxNewSize)) {
    max_new_size = MaxNewSize;
  } else {
    max_new_size = scale_by_NewRatio_aligned(_max_heap_byte_size);
    // Bound the maximum size by NewSize below (since it historically
    // would have been NewSize and because the NewRatio calculation could
    // yield a size that is too small) and bound it by MaxNewSize above.
    // Ergonomics plays here by previously calculating the desired
    // NewSize and MaxNewSize.
    max_new_size = MIN2(MAX2(max_new_size, NewSize), MaxNewSize);
  }
  assert(max_new_size > 0, "All paths should set max_new_size");

  // Given the maximum gen0 size, determine the initial and
  // minimum gen0 sizes.

  if (_max_heap_byte_size == _min_heap_byte_size) {
    // The maximum and minimum heap sizes are the same so
    // the generations minimum and initial must be the
    // same as its maximum.
    _min_gen0_size = max_new_size;
    _initial_gen0_size = max_new_size;
    _max_gen0_size = max_new_size;
  } else {
    size_t desired_new_size = 0;
    if (FLAG_IS_CMDLINE(NewSize)) {
      // If NewSize is set on the command line, we must use it as
      // the initial size and it also makes sense to use it as the
      // lower limit.
      _min_gen0_size = NewSize;
      desired_new_size = NewSize;
      max_new_size = MAX2(max_new_size, NewSize);
    } else if (FLAG_IS_ERGO(NewSize)) {
      // If NewSize is set ergonomically, we should use it as a lower
      // limit, but use NewRatio to calculate the initial size.
      _min_gen0_size = NewSize;
      desired_new_size =
        MAX2(scale_by_NewRatio_aligned(_initial_heap_byte_size), NewSize);
      max_new_size = MAX2(max_new_size, NewSize);
    } else {
      // For the case where NewSize is the default, use NewRatio
      // to size the minimum and initial generation sizes.
      // Use the default NewSize as the floor for these values.  If
      // NewRatio is overly large, the resulting sizes can be too
      // small.
      _min_gen0_size = MAX2(scale_by_NewRatio_aligned(_min_heap_byte_size), NewSize);
      desired_new_size =
        MAX2(scale_by_NewRatio_aligned(_initial_heap_byte_size), NewSize);
    }

    assert(_min_gen0_size > 0, "Sanity check");
    _initial_gen0_size = desired_new_size;
    _max_gen0_size = max_new_size;

    // At this point the desirable initial and minimum sizes have been
    // determined without regard to the maximum sizes.

    // Bound the sizes by the corresponding overall heap sizes.
    _min_gen0_size = bound_minus_alignment(_min_gen0_size, _min_heap_byte_size);
    _initial_gen0_size = bound_minus_alignment(_initial_gen0_size, _initial_heap_byte_size);
    _max_gen0_size = bound_minus_alignment(_max_gen0_size, _max_heap_byte_size);

    // At this point all three sizes have been checked against the
    // maximum sizes but have not been checked for consistency
    // among the three.

    // Final check min <= initial <= max
    _min_gen0_size = MIN2(_min_gen0_size, _max_gen0_size);
    _initial_gen0_size = MAX2(MIN2(_initial_gen0_size, _max_gen0_size), _min_gen0_size);
    _min_gen0_size = MIN2(_min_gen0_size, _initial_gen0_size);
  }

  // Write back to flags if necessary
  if (NewSize != _initial_gen0_size) {
    FLAG_SET_ERGO(uintx, NewSize, _initial_gen0_size);
  }

  if (MaxNewSize != _max_gen0_size) {
    FLAG_SET_ERGO(uintx, MaxNewSize, _max_gen0_size);
  }

  if (PrintGCDetails && Verbose) {
    gclog_or_tty->print_cr("1: Minimum gen0 " SIZE_FORMAT "  Initial gen0 "
      SIZE_FORMAT "  Maximum gen0 " SIZE_FORMAT,
      _min_gen0_size, _initial_gen0_size, _max_gen0_size);
  }

  DEBUG_ONLY(GenCollectorPolicy::assert_size_info();)
}
Exemplo n.º 5
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void TwoGenerationCollectorPolicy::initialize_size_info() {
  GenCollectorPolicy::initialize_size_info();

  // At this point the minimum, initial and maximum sizes
  // of the overall heap and of gen0 have been determined.
  // The maximum gen1 size can be determined from the maximum gen0
  // and maximum heap size since not explicit flags exits
  // for setting the gen1 maximum.
  _max_gen1_size = max_heap_byte_size() - _max_gen0_size;
  _max_gen1_size =
    MAX2((size_t)align_size_down(_max_gen1_size, min_alignment()),
         min_alignment());
  // If no explicit command line flag has been set for the
  // gen1 size, use what is left for gen1.
  if (FLAG_IS_DEFAULT(OldSize) || FLAG_IS_ERGO(OldSize)) {
    // The user has not specified any value or ergonomics
    // has chosen a value (which may or may not be consistent
    // with the overall heap size).  In either case make
    // the minimum, maximum and initial sizes consistent
    // with the gen0 sizes and the overall heap sizes.
    assert(min_heap_byte_size() > _min_gen0_size,
      "gen0 has an unexpected minimum size");
    set_min_gen1_size(min_heap_byte_size() - min_gen0_size());
    set_min_gen1_size(
      MAX2((size_t)align_size_down(_min_gen1_size, min_alignment()),
           min_alignment()));
    set_initial_gen1_size(initial_heap_byte_size() - initial_gen0_size());
    set_initial_gen1_size(
      MAX2((size_t)align_size_down(_initial_gen1_size, min_alignment()),
           min_alignment()));

  } else {
    // It's been explicitly set on the command line.  Use the
    // OldSize and then determine the consequences.
    set_min_gen1_size(OldSize);
    set_initial_gen1_size(OldSize);

    // If the user has explicitly set an OldSize that is inconsistent
    // with other command line flags, issue a warning.
    // The generation minimums and the overall heap mimimum should
    // be within one heap alignment.
    if ((_min_gen1_size + _min_gen0_size + min_alignment()) <
           min_heap_byte_size()) {
      warning("Inconsistency between minimum heap size and minimum "
          "generation sizes: using minimum heap = " SIZE_FORMAT,
          min_heap_byte_size());
    }
    if ((OldSize > _max_gen1_size)) {
      warning("Inconsistency between maximum heap size and maximum "
          "generation sizes: using maximum heap = " SIZE_FORMAT
          " -XX:OldSize flag is being ignored",
          max_heap_byte_size());
  }
    // If there is an inconsistency between the OldSize and the minimum and/or
    // initial size of gen0, since OldSize was explicitly set, OldSize wins.
    if (adjust_gen0_sizes(&_min_gen0_size, &_min_gen1_size,
                          min_heap_byte_size(), OldSize)) {
      if (PrintGCDetails && Verbose) {
        gclog_or_tty->print_cr("Minimum gen0 " SIZE_FORMAT "  Initial gen0 "
              SIZE_FORMAT "  Maximum gen0 " SIZE_FORMAT,
              min_gen0_size(), initial_gen0_size(), max_gen0_size());
      }
    }
    // Initial size
    if (adjust_gen0_sizes(&_initial_gen0_size, &_initial_gen1_size,
                         initial_heap_byte_size(), OldSize)) {
      if (PrintGCDetails && Verbose) {
        gclog_or_tty->print_cr("Minimum gen0 " SIZE_FORMAT "  Initial gen0 "
          SIZE_FORMAT "  Maximum gen0 " SIZE_FORMAT,
          min_gen0_size(), initial_gen0_size(), max_gen0_size());
      }
    }
  }
  // Enforce the maximum gen1 size.
  set_min_gen1_size(MIN2(_min_gen1_size, _max_gen1_size));

  // Check that min gen1 <= initial gen1 <= max gen1
  set_initial_gen1_size(MAX2(_initial_gen1_size, _min_gen1_size));
  set_initial_gen1_size(MIN2(_initial_gen1_size, _max_gen1_size));

  if (PrintGCDetails && Verbose) {
    gclog_or_tty->print_cr("Minimum gen1 " SIZE_FORMAT "  Initial gen1 "
      SIZE_FORMAT "  Maximum gen1 " SIZE_FORMAT,
      min_gen1_size(), initial_gen1_size(), max_gen1_size());
  }
}
Exemplo n.º 6
0
// Call an accessor method (assuming it is resolved, otherwise drop into
// vanilla (slow path) entry.
address InterpreterGenerator::generate_accessor_entry(void) {
  if (!UseFastAccessorMethods && (!FLAG_IS_ERGO(UseFastAccessorMethods))) {
    return NULL;
  }

  Label Lslow_path, Lacquire;

  const Register
         Rclass_or_obj = R3_ARG1,
         Rconst_method = R4_ARG2,
         Rcodes        = Rconst_method,
         Rcpool_cache  = R5_ARG3,
         Rscratch      = R11_scratch1,
         Rjvmti_mode   = Rscratch,
         Roffset       = R12_scratch2,
         Rflags        = R6_ARG4,
         Rbtable       = R7_ARG5;

  static address branch_table[number_of_states];

  address entry = __ pc();

  // Check for safepoint:
  // Ditch this, real man don't need safepoint checks.

  // Also check for JVMTI mode
  // Check for null obj, take slow path if so.
  __ ld(Rclass_or_obj, Interpreter::stackElementSize, CC_INTERP_ONLY(R17_tos) NOT_CC_INTERP(R15_esp));
  __ lwz(Rjvmti_mode, thread_(interp_only_mode));
  __ cmpdi(CCR1, Rclass_or_obj, 0);
  __ cmpwi(CCR0, Rjvmti_mode, 0);
  __ crorc(/*CCR0 eq*/2, /*CCR1 eq*/4+2, /*CCR0 eq*/2);
  __ beq(CCR0, Lslow_path); // this==null or jvmti_mode!=0

  // Do 2 things in parallel:
  // 1. Load the index out of the first instruction word, which looks like this:
  //    <0x2a><0xb4><index (2 byte, native endianess)>.
  // 2. Load constant pool cache base.
  __ ld(Rconst_method, in_bytes(Method::const_offset()), R19_method);
  __ ld(Rcpool_cache, in_bytes(ConstMethod::constants_offset()), Rconst_method);

  __ lhz(Rcodes, in_bytes(ConstMethod::codes_offset()) + 2, Rconst_method); // Lower half of 32 bit field.
  __ ld(Rcpool_cache, ConstantPool::cache_offset_in_bytes(), Rcpool_cache);

  // Get the const pool entry by means of <index>.
  const int codes_shift = exact_log2(in_words(ConstantPoolCacheEntry::size()) * BytesPerWord);
  __ slwi(Rscratch, Rcodes, codes_shift); // (codes&0xFFFF)<<codes_shift
  __ add(Rcpool_cache, Rscratch, Rcpool_cache);

  // Check if cpool cache entry is resolved.
  // We are resolved if the indices offset contains the current bytecode.
  ByteSize cp_base_offset = ConstantPoolCache::base_offset();
  // Big Endian:
  __ lbz(Rscratch, in_bytes(cp_base_offset) + in_bytes(ConstantPoolCacheEntry::indices_offset()) + 7 - 2, Rcpool_cache);
  __ cmpwi(CCR0, Rscratch, Bytecodes::_getfield);
  __ bne(CCR0, Lslow_path);
  __ isync(); // Order succeeding loads wrt. load of _indices field from cpool_cache.

  // Finally, start loading the value: Get cp cache entry into regs.
  __ ld(Rflags, in_bytes(cp_base_offset) + in_bytes(ConstantPoolCacheEntry::flags_offset()), Rcpool_cache);
  __ ld(Roffset, in_bytes(cp_base_offset) + in_bytes(ConstantPoolCacheEntry::f2_offset()), Rcpool_cache);

  // Following code is from templateTable::getfield_or_static
  // Load pointer to branch table
  __ load_const_optimized(Rbtable, (address)branch_table, Rscratch);

  // Get volatile flag
  __ rldicl(Rscratch, Rflags, 64-ConstantPoolCacheEntry::is_volatile_shift, 63); // extract volatile bit
  // note: sync is needed before volatile load on PPC64

  // Check field type
  __ rldicl(Rflags, Rflags, 64-ConstantPoolCacheEntry::tos_state_shift, 64-ConstantPoolCacheEntry::tos_state_bits);

#ifdef ASSERT
  Label LFlagInvalid;
  __ cmpldi(CCR0, Rflags, number_of_states);
  __ bge(CCR0, LFlagInvalid);

  __ ld(R9_ARG7, 0, R1_SP);
  __ ld(R10_ARG8, 0, R21_sender_SP);
  __ cmpd(CCR0, R9_ARG7, R10_ARG8);
  __ asm_assert_eq("backlink", 0x543);
#endif // ASSERT
  __ mr(R1_SP, R21_sender_SP); // Cut the stack back to where the caller started.

  // Load from branch table and dispatch (volatile case: one instruction ahead)
  __ sldi(Rflags, Rflags, LogBytesPerWord);
  __ cmpwi(CCR6, Rscratch, 1); // volatile?
  if (support_IRIW_for_not_multiple_copy_atomic_cpu) {
    __ sldi(Rscratch, Rscratch, exact_log2(BytesPerInstWord)); // volatile ? size of 1 instruction : 0
  }
  __ ldx(Rbtable, Rbtable, Rflags);

  if (support_IRIW_for_not_multiple_copy_atomic_cpu) {
    __ subf(Rbtable, Rscratch, Rbtable); // point to volatile/non-volatile entry point
  }
  __ mtctr(Rbtable);
  __ bctr();

#ifdef ASSERT
  __ bind(LFlagInvalid);
  __ stop("got invalid flag", 0x6541);

  bool all_uninitialized = true,
       all_initialized   = true;
  for (int i = 0; i<number_of_states; ++i) {
    all_uninitialized = all_uninitialized && (branch_table[i] == NULL);
    all_initialized   = all_initialized   && (branch_table[i] != NULL);
  }
  assert(all_uninitialized != all_initialized, "consistency"); // either or

  __ fence(); // volatile entry point (one instruction before non-volatile_entry point)
  if (branch_table[vtos] == 0) branch_table[vtos] = __ pc(); // non-volatile_entry point
  if (branch_table[dtos] == 0) branch_table[dtos] = __ pc(); // non-volatile_entry point
  if (branch_table[ftos] == 0) branch_table[ftos] = __ pc(); // non-volatile_entry point
  __ stop("unexpected type", 0x6551);
#endif

  if (branch_table[itos] == 0) { // generate only once
    __ align(32, 28, 28); // align load
    __ fence(); // volatile entry point (one instruction before non-volatile_entry point)
    branch_table[itos] = __ pc(); // non-volatile_entry point
    __ lwax(R3_RET, Rclass_or_obj, Roffset);
    __ beq(CCR6, Lacquire);
    __ blr();
  }

  if (branch_table[ltos] == 0) { // generate only once
    __ align(32, 28, 28); // align load
    __ fence(); // volatile entry point (one instruction before non-volatile_entry point)
    branch_table[ltos] = __ pc(); // non-volatile_entry point
    __ ldx(R3_RET, Rclass_or_obj, Roffset);
    __ beq(CCR6, Lacquire);
    __ blr();
  }

  if (branch_table[btos] == 0) { // generate only once
    __ align(32, 28, 28); // align load
    __ fence(); // volatile entry point (one instruction before non-volatile_entry point)
    branch_table[btos] = __ pc(); // non-volatile_entry point
    __ lbzx(R3_RET, Rclass_or_obj, Roffset);
    __ extsb(R3_RET, R3_RET);
    __ beq(CCR6, Lacquire);
    __ blr();
  }

  if (branch_table[ctos] == 0) { // generate only once
    __ align(32, 28, 28); // align load
    __ fence(); // volatile entry point (one instruction before non-volatile_entry point)
    branch_table[ctos] = __ pc(); // non-volatile_entry point
    __ lhzx(R3_RET, Rclass_or_obj, Roffset);
    __ beq(CCR6, Lacquire);
    __ blr();
  }

  if (branch_table[stos] == 0) { // generate only once
    __ align(32, 28, 28); // align load
    __ fence(); // volatile entry point (one instruction before non-volatile_entry point)
    branch_table[stos] = __ pc(); // non-volatile_entry point
    __ lhax(R3_RET, Rclass_or_obj, Roffset);
    __ beq(CCR6, Lacquire);
    __ blr();
  }

  if (branch_table[atos] == 0) { // generate only once
    __ align(32, 28, 28); // align load
    __ fence(); // volatile entry point (one instruction before non-volatile_entry point)
    branch_table[atos] = __ pc(); // non-volatile_entry point
    __ load_heap_oop(R3_RET, (RegisterOrConstant)Roffset, Rclass_or_obj);
    __ verify_oop(R3_RET);
    //__ dcbt(R3_RET); // prefetch
    __ beq(CCR6, Lacquire);
    __ blr();
  }

  __ align(32, 12);
  __ bind(Lacquire);
  __ twi_0(R3_RET);
  __ isync(); // acquire
  __ blr();

#ifdef ASSERT
  for (int i = 0; i<number_of_states; ++i) {
    assert(branch_table[i], "accessor_entry initialization");
    //tty->print_cr("accessor_entry: branch_table[%d] = 0x%llx (opcode 0x%llx)", i, branch_table[i], *((unsigned int*)branch_table[i]));
  }
#endif

  __ bind(Lslow_path);
  __ branch_to_entry(Interpreter::entry_for_kind(Interpreter::zerolocals), Rscratch);
  __ flush();

  return entry;
}
Exemplo n.º 7
0
// Values set on the command line win over any ergonomically
// set command line parameters.
// Ergonomic choice of parameters are done before this
// method is called.  Values for command line parameters such as NewSize
// and MaxNewSize feed those ergonomic choices into this method.
// This method makes the final generation sizings consistent with
// themselves and with overall heap sizings.
// In the absence of explicitly set command line flags, policies
// such as the use of NewRatio are used to size the generation.
void GenCollectorPolicy::initialize_size_info() {
  CollectorPolicy::initialize_size_info();

  // min_alignment() is used for alignment within a generation.
  // There is additional alignment done down stream for some
  // collectors that sometimes causes unwanted rounding up of
  // generations sizes.

  // Determine maximum size of gen0

  size_t max_new_size = 0;
  if (FLAG_IS_CMDLINE(MaxNewSize) || FLAG_IS_ERGO(MaxNewSize)) {
    if (MaxNewSize < min_alignment()) {
      max_new_size = min_alignment();
    }
    if (MaxNewSize >= max_heap_byte_size()) {
      max_new_size = align_size_down(max_heap_byte_size() - min_alignment(),
                                     min_alignment());
      warning("MaxNewSize (" SIZE_FORMAT "k) is equal to or "
        "greater than the entire heap (" SIZE_FORMAT "k).  A "
        "new generation size of " SIZE_FORMAT "k will be used.",
        MaxNewSize/K, max_heap_byte_size()/K, max_new_size/K);
    } else {
      max_new_size = align_size_down(MaxNewSize, min_alignment());
    }

  // The case for FLAG_IS_ERGO(MaxNewSize) could be treated
  // specially at this point to just use an ergonomically set
  // MaxNewSize to set max_new_size.  For cases with small
  // heaps such a policy often did not work because the MaxNewSize
  // was larger than the entire heap.  The interpretation given
  // to ergonomically set flags is that the flags are set
  // by different collectors for their own special needs but
  // are not allowed to badly shape the heap.  This allows the
  // different collectors to decide what's best for themselves
  // without having to factor in the overall heap shape.  It
  // can be the case in the future that the collectors would
  // only make "wise" ergonomics choices and this policy could
  // just accept those choices.  The choices currently made are
  // not always "wise".
  } else {
    max_new_size = scale_by_NewRatio_aligned(max_heap_byte_size());
    // Bound the maximum size by NewSize below (since it historically
    // would have been NewSize and because the NewRatio calculation could
    // yield a size that is too small) and bound it by MaxNewSize above.
    // Ergonomics plays here by previously calculating the desired
    // NewSize and MaxNewSize.
    max_new_size = MIN2(MAX2(max_new_size, (size_t) NewSize), (size_t) MaxNewSize);
  }
  assert(max_new_size > 0, "All paths should set max_new_size");

  // Given the maximum gen0 size, determine the initial and
  // minimum gen0 sizes.

  if (max_heap_byte_size() == min_heap_byte_size()) {
    // The maximum and minimum heap sizes are the same so
    // the generations minimum and initial must be the
    // same as its maximum.
    set_min_gen0_size(max_new_size);
    set_initial_gen0_size(max_new_size);
    set_max_gen0_size(max_new_size);
  } else {
    size_t desired_new_size = 0;
    if (!FLAG_IS_DEFAULT(NewSize)) {
      // If NewSize is set ergonomically (for example by cms), it
      // would make sense to use it.  If it is used, also use it
      // to set the initial size.  Although there is no reason
      // the minimum size and the initial size have to be the same,
      // the current implementation gets into trouble during the calculation
      // of the tenured generation sizes if they are different.
      // Note that this makes the initial size and the minimum size
      // generally small compared to the NewRatio calculation.
      _min_gen0_size = NewSize;
      desired_new_size = NewSize;
      max_new_size = MAX2(max_new_size, NewSize);
    } else {
      // For the case where NewSize is the default, use NewRatio
      // to size the minimum and initial generation sizes.
      // Use the default NewSize as the floor for these values.  If
      // NewRatio is overly large, the resulting sizes can be too
      // small.
      _min_gen0_size = MAX2(scale_by_NewRatio_aligned(min_heap_byte_size()),
                          NewSize);
      desired_new_size =
        MAX2(scale_by_NewRatio_aligned(initial_heap_byte_size()),
             NewSize);
    }

    assert(_min_gen0_size > 0, "Sanity check");
    set_initial_gen0_size(desired_new_size);
    set_max_gen0_size(max_new_size);

    // At this point the desirable initial and minimum sizes have been
    // determined without regard to the maximum sizes.

    // Bound the sizes by the corresponding overall heap sizes.
    set_min_gen0_size(
      bound_minus_alignment(_min_gen0_size, min_heap_byte_size()));
    set_initial_gen0_size(
      bound_minus_alignment(_initial_gen0_size, initial_heap_byte_size()));
    set_max_gen0_size(
      bound_minus_alignment(_max_gen0_size, max_heap_byte_size()));

    // At this point all three sizes have been checked against the
    // maximum sizes but have not been checked for consistency
    // among the three.

    // Final check min <= initial <= max
    set_min_gen0_size(MIN2(_min_gen0_size, _max_gen0_size));
    set_initial_gen0_size(
      MAX2(MIN2(_initial_gen0_size, _max_gen0_size), _min_gen0_size));
    set_min_gen0_size(MIN2(_min_gen0_size, _initial_gen0_size));
  }

  if (PrintGCDetails && Verbose) {
    gclog_or_tty->print_cr("1: Minimum gen0 " SIZE_FORMAT "  Initial gen0 "
      SIZE_FORMAT "  Maximum gen0 " SIZE_FORMAT,
      min_gen0_size(), initial_gen0_size(), max_gen0_size());
  }
}