8329096: G1: Change the type of G1BlockOffsetTable::_offset_base to uint8_t*

Reviewed-by: ayang, tschatzl
This commit is contained in:
Guoxiong Li 2024-03-28 04:03:16 +00:00
parent 3eb1d05d85
commit 4fa77a2ad4
3 changed files with 49 additions and 50 deletions

@ -40,7 +40,7 @@ G1BlockOffsetTable::G1BlockOffsetTable(MemRegion heap, G1RegionToSpaceMapper* st
MemRegion bot_reserved = storage->reserved();
_offset_base = ((u_char*)bot_reserved.start() - (uintptr_t(_reserved.start()) >> CardTable::card_shift()));
_offset_base = ((uint8_t*)bot_reserved.start() - (uintptr_t(_reserved.start()) >> CardTable::card_shift()));
log_trace(gc, bot)("G1BlockOffsetTable::G1BlockOffsetTable: ");
log_trace(gc, bot)(" rs.base(): " PTR_FORMAT " rs.size(): " SIZE_FORMAT " rs end(): " PTR_FORMAT,
@ -48,9 +48,9 @@ G1BlockOffsetTable::G1BlockOffsetTable(MemRegion heap, G1RegionToSpaceMapper* st
}
#ifdef ASSERT
void G1BlockOffsetTable::check_address(u_char* addr, const char* msg) const {
u_char* start_addr = const_cast<u_char *>(_offset_base + (uintptr_t(_reserved.start()) >> CardTable::card_shift()));
u_char* end_addr = const_cast<u_char *>(_offset_base + (uintptr_t(_reserved.end()) >> CardTable::card_shift()));
void G1BlockOffsetTable::check_address(uint8_t* addr, const char* msg) const {
uint8_t* start_addr = const_cast<uint8_t*>(_offset_base + (uintptr_t(_reserved.start()) >> CardTable::card_shift()));
uint8_t* end_addr = const_cast<uint8_t*>(_offset_base + (uintptr_t(_reserved.end()) >> CardTable::card_shift()));
assert(addr >= start_addr && addr <= end_addr,
"%s - offset address: " PTR_FORMAT ", start address: " PTR_FORMAT ", end address: " PTR_FORMAT,
msg, (p2i(addr)), (p2i(start_addr)), (p2i(end_addr)));
@ -102,18 +102,18 @@ G1BlockOffsetTablePart::G1BlockOffsetTablePart(G1BlockOffsetTable* array, HeapRe
// Move back N (e.g., 8) entries and repeat with the
// value of the new entry
//
void G1BlockOffsetTablePart::set_remainder_to_point_to_start_incl(u_char* start_card, u_char* end_card) {
void G1BlockOffsetTablePart::set_remainder_to_point_to_start_incl(uint8_t* start_card, uint8_t* end_card) {
assert(start_card <= end_card, "precondition");
assert(start_card > _bot->entry_for_addr(_hr->bottom()), "Cannot be first card");
assert(_bot->offset_array(start_card-1) < CardTable::card_size_in_words(),
"Offset card has an unexpected value");
u_char* start_card_for_region = start_card;
u_char offset = max_jubyte;
uint8_t* start_card_for_region = start_card;
uint8_t offset = UINT8_MAX;
for (uint i = 0; i < BOTConstants::N_powers; i++) {
// -1 so that the card with the actual offset is counted. Another -1
// so that the reach ends in this region and not at the start
// of the next.
u_char* reach = start_card - 1 + (BOTConstants::power_to_cards_back(i+1) - 1);
uint8_t* reach = start_card - 1 + (BOTConstants::power_to_cards_back(i+1) - 1);
offset = CardTable::card_size_in_words() + i;
if (reach >= end_card) {
_bot->set_offset_array(start_card_for_region, end_card, offset);
@ -131,13 +131,13 @@ void G1BlockOffsetTablePart::set_remainder_to_point_to_start_incl(u_char* start_
// The card-interval [start_card, end_card] is a closed interval; this
// is an expensive check -- use with care and only under protection of
// suitable flag.
void G1BlockOffsetTablePart::check_all_cards(u_char* start_card, u_char* end_card) const {
void G1BlockOffsetTablePart::check_all_cards(uint8_t* start_card, uint8_t* end_card) const {
if (end_card < start_card) {
return;
}
guarantee(_bot->offset_array(start_card) == CardTable::card_size_in_words(), "Wrong value in second card");
for (u_char* c = start_card + 1; c <= end_card; c++ /* yeah! */) {
u_char entry = _bot->offset_array(c);
for (uint8_t* c = start_card + 1; c <= end_card; c++ /* yeah! */) {
uint8_t entry = _bot->offset_array(c);
if ((unsigned)(c - start_card) > BOTConstants::power_to_cards_back(1)) {
guarantee(entry > CardTable::card_size_in_words(),
"Should be in logarithmic region - "
@ -147,7 +147,7 @@ void G1BlockOffsetTablePart::check_all_cards(u_char* start_card, u_char* end_car
(uint)entry, (uint)_bot->offset_array(c), CardTable::card_size_in_words());
}
size_t backskip = BOTConstants::entry_to_cards_back(entry);
u_char* landing_card = c - backskip;
uint8_t* landing_card = c - backskip;
guarantee(landing_card >= (start_card - 1), "Inv");
if (landing_card >= start_card) {
guarantee(_bot->offset_array(landing_card) <= entry,
@ -179,7 +179,7 @@ void G1BlockOffsetTablePart::check_all_cards(u_char* start_card, u_char* end_car
void G1BlockOffsetTablePart::update_for_block_work(HeapWord* blk_start,
HeapWord* blk_end) {
HeapWord* const cur_card_boundary = align_up_by_card_size(blk_start);
u_char* const offset_card = _bot->entry_for_addr(cur_card_boundary);
uint8_t* const offset_card = _bot->entry_for_addr(cur_card_boundary);
assert(blk_start != nullptr && blk_end > blk_start,
"phantom block");
@ -200,7 +200,7 @@ void G1BlockOffsetTablePart::update_for_block_work(HeapWord* blk_start,
// We need to now mark the subsequent cards that this block spans.
// Index of card on which the block ends.
u_char* end_card = _bot->entry_for_addr(blk_end - 1);
uint8_t* end_card = _bot->entry_for_addr(blk_end - 1);
// Are there more cards left to be updated?
if (offset_card + 1 <= end_card) {
@ -215,7 +215,7 @@ void G1BlockOffsetTablePart::update_for_block_work(HeapWord* blk_start,
// The offset can be 0 if the block starts on a boundary. That
// is checked by an assertion above.
u_char* previous_card = _bot->entry_for_addr(blk_start);
uint8_t* previous_card = _bot->entry_for_addr(blk_start);
HeapWord* boundary = _bot->addr_for_entry(previous_card);
assert((_bot->offset_array(offset_card) == 0 && blk_start == boundary) ||
(_bot->offset_array(offset_card) > 0 && _bot->offset_array(offset_card) < CardTable::card_size_in_words()),
@ -225,10 +225,10 @@ void G1BlockOffsetTablePart::update_for_block_work(HeapWord* blk_start,
"boundary: " PTR_FORMAT,
(uint)_bot->offset_array(offset_card),
p2i(blk_start), p2i(boundary));
for (u_char* j = offset_card + 1; j <= end_card; j++) {
for (uint8_t* j = offset_card + 1; j <= end_card; j++) {
assert(_bot->offset_array(j) > 0 &&
_bot->offset_array(j) <=
(u_char) (CardTable::card_size_in_words() + BOTConstants::N_powers - 1),
(uint8_t) (CardTable::card_size_in_words() + BOTConstants::N_powers - 1),
"offset array should have been set - "
"%u not > 0 OR %u not <= %u",
(uint) _bot->offset_array(j),
@ -240,11 +240,11 @@ void G1BlockOffsetTablePart::update_for_block_work(HeapWord* blk_start,
void G1BlockOffsetTablePart::verify() const {
assert(_hr->bottom() < _hr->top(), "Only non-empty regions should be verified.");
u_char* start_card = _bot->entry_for_addr(_hr->bottom());
u_char* end_card = _bot->entry_for_addr(_hr->top() - 1);
uint8_t* start_card = _bot->entry_for_addr(_hr->bottom());
uint8_t* end_card = _bot->entry_for_addr(_hr->top() - 1);
for (u_char* current_card = start_card; current_card < end_card; current_card++) {
u_char entry = _bot->offset_array(current_card);
for (uint8_t* current_card = start_card; current_card < end_card; current_card++) {
uint8_t entry = _bot->offset_array(current_card);
if (entry < CardTable::card_size_in_words()) {
// The entry should point to an object before the current card. Verify that
// it is possible to walk from that object in to the current card by just
@ -281,12 +281,12 @@ void G1BlockOffsetTablePart::verify() const {
#ifndef PRODUCT
void G1BlockOffsetTablePart::print_on(outputStream* out) {
u_char* from_card = _bot->entry_for_addr(_hr->bottom());
u_char* to_card = _bot->entry_for_addr(_hr->end());
uint8_t* from_card = _bot->entry_for_addr(_hr->bottom());
uint8_t* to_card = _bot->entry_for_addr(_hr->end());
out->print_cr(">> BOT for area [" PTR_FORMAT "," PTR_FORMAT ") "
"cards [" SIZE_FORMAT "," SIZE_FORMAT ")",
p2i(_hr->bottom()), p2i(_hr->end()), p2i(from_card), p2i(to_card));
for (u_char* i = from_card; i < to_card; ++i) {
for (uint8_t* i = from_card; i < to_card; ++i) {
out->print_cr(" entry " SIZE_FORMAT_W(8) " | " PTR_FORMAT " : %3u",
p2i(i), p2i(_bot->addr_for_entry(i)),
(uint) _bot->offset_array(i));

@ -52,7 +52,7 @@ private:
MemRegion _reserved;
// Biased array-start of BOT array for fast BOT entry translation
volatile u_char* _offset_base;
volatile uint8_t* _offset_base;
void check_offset(size_t offset, const char* msg) const {
assert(offset < CardTable::card_size_in_words(),
@ -62,16 +62,16 @@ private:
// Bounds checking accessors:
// For performance these have to devolve to array accesses in product builds.
inline u_char offset_array(u_char* addr) const;
inline uint8_t offset_array(uint8_t* addr) const;
inline void set_offset_array_raw(u_char* addr, u_char offset);
inline void set_offset_array(u_char* addr, u_char offset);
inline void set_offset_array_raw(uint8_t* addr, uint8_t offset);
inline void set_offset_array(uint8_t* addr, uint8_t offset);
inline void set_offset_array(u_char* addr, HeapWord* high, HeapWord* low);
inline void set_offset_array(uint8_t* addr, HeapWord* high, HeapWord* low);
inline void set_offset_array(u_char* left, u_char* right, u_char offset);
inline void set_offset_array(uint8_t* left, uint8_t* right, uint8_t offset);
void check_address(u_char* addr, const char* msg) const NOT_DEBUG_RETURN;
void check_address(uint8_t* addr, const char* msg) const NOT_DEBUG_RETURN;
public:
@ -92,10 +92,10 @@ public:
G1BlockOffsetTable(MemRegion heap, G1RegionToSpaceMapper* storage);
// Mapping from address to object start array entry
u_char* entry_for_addr(const void* const p) const;
uint8_t* entry_for_addr(const void* const p) const;
// Mapping from object start array entry to address of first word
HeapWord* addr_for_entry(const u_char* const p) const;
HeapWord* addr_for_entry(const uint8_t* const p) const;
};
class G1BlockOffsetTablePart {
@ -110,12 +110,12 @@ private:
// Sets the entries corresponding to the cards starting at "start" and ending
// at "end" to point back to the card before "start"; [start, end]
void set_remainder_to_point_to_start_incl(u_char* start, u_char* end);
void set_remainder_to_point_to_start_incl(uint8_t* start, uint8_t* end);
// Update BOT entries corresponding to the mem range [blk_start, blk_end).
void update_for_block_work(HeapWord* blk_start, HeapWord* blk_end);
void check_all_cards(u_char* left_card, u_char* right_card) const NOT_DEBUG_RETURN;
void check_all_cards(uint8_t* left_card, uint8_t* right_card) const NOT_DEBUG_RETURN;
static HeapWord* align_up_by_card_size(HeapWord* const addr) {
return align_up(addr, CardTable::card_size());

@ -38,14 +38,14 @@ inline HeapWord* G1BlockOffsetTablePart::block_start_reaching_into_card(const vo
#ifdef ASSERT
if (!_hr->is_continues_humongous()) {
// For non-ContinuesHumongous regions, the first obj always starts from bottom.
u_char offset = _bot->offset_array(_bot->entry_for_addr(_hr->bottom()));
uint8_t offset = _bot->offset_array(_bot->entry_for_addr(_hr->bottom()));
assert(offset == 0, "Found offset %u instead of 0 for region %u %s",
offset, _hr->hrm_index(), _hr->get_short_type_str());
}
#endif
u_char* entry = _bot->entry_for_addr(addr);
u_char offset = _bot->offset_array(entry);
uint8_t* entry = _bot->entry_for_addr(addr);
uint8_t offset = _bot->offset_array(entry);
while (offset >= CardTable::card_size_in_words()) {
// The excess of the offset from N_words indicates a power of Base
// to go back by.
@ -58,45 +58,44 @@ inline HeapWord* G1BlockOffsetTablePart::block_start_reaching_into_card(const vo
return q - offset;
}
u_char G1BlockOffsetTable::offset_array(u_char* addr) const {
uint8_t G1BlockOffsetTable::offset_array(uint8_t* addr) const {
check_address(addr, "Block offset table address out of range");
return Atomic::load(addr);
}
void G1BlockOffsetTable::set_offset_array_raw(u_char* addr, u_char offset) {
void G1BlockOffsetTable::set_offset_array_raw(uint8_t* addr, uint8_t offset) {
Atomic::store(addr, offset);
}
void G1BlockOffsetTable::set_offset_array(u_char* addr, u_char offset) {
void G1BlockOffsetTable::set_offset_array(uint8_t* addr, uint8_t offset) {
check_address(addr, "Block offset table address out of range");
set_offset_array_raw(addr, offset);
}
void G1BlockOffsetTable::set_offset_array(u_char* addr, HeapWord* high, HeapWord* low) {
void G1BlockOffsetTable::set_offset_array(uint8_t* addr, HeapWord* high, HeapWord* low) {
check_address(addr, "Block offset table address out of range");
assert(high >= low, "addresses out of order");
size_t offset = pointer_delta(high, low);
check_offset(offset, "offset too large");
set_offset_array(addr, (u_char)offset);
set_offset_array(addr, (uint8_t)offset);
}
void G1BlockOffsetTable::set_offset_array(u_char* left, u_char* right, u_char offset) {
void G1BlockOffsetTable::set_offset_array(uint8_t* left, uint8_t* right, uint8_t offset) {
check_address(right, "Right block offset table address out of range");
assert(left <= right, "indexes out of order");
size_t num_cards = right - left + 1;
memset_with_concurrent_readers
(const_cast<u_char*> (left), offset, num_cards);
memset_with_concurrent_readers(left, offset, num_cards);
}
inline u_char* G1BlockOffsetTable::entry_for_addr(const void* const p) const {
inline uint8_t* G1BlockOffsetTable::entry_for_addr(const void* const p) const {
assert(_reserved.contains(p),
"out of bounds access to block offset table");
u_char* result = const_cast<u_char *>(&_offset_base[uintptr_t(p) >> CardTable::card_shift()]);
uint8_t* result = const_cast<uint8_t*>(&_offset_base[uintptr_t(p) >> CardTable::card_shift()]);
return result;
}
inline HeapWord* G1BlockOffsetTable::addr_for_entry(const u_char* const p) const {
size_t delta = pointer_delta(p, _offset_base, sizeof(u_char));
inline HeapWord* G1BlockOffsetTable::addr_for_entry(const uint8_t* const p) const {
size_t delta = pointer_delta(p, _offset_base, sizeof(uint8_t));
HeapWord* result = (HeapWord*) (delta << CardTable::card_shift());
assert(_reserved.contains(result),
"out of bounds accessor from block offset table");