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);
}
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();)
}
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());
}
}
// 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;
}
// 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());
}
}