8233061: ZGC: Enforce memory ordering in segmented bit maps
Reviewed-by: pliden, stefank
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#ifndef SHARE_GC_Z_ZADDRESS_INLINE_HPP
#define SHARE_GC_Z_ZADDRESS_INLINE_HPP
#include "gc/z/zAddress.hpp"
#include "gc/z/zGlobals.hpp"
#include "utilities/globalDefinitions.hpp"
#include "utilities/macros.hpp"
inline bool ZAddress::is_null(uintptr_t value) {
return value == 0;
}
inline bool ZAddress::is_bad(uintptr_t value) {
return value & ZAddressBadMask;
}
inline bool ZAddress::is_good(uintptr_t value) {
return !is_bad(value) && !is_null(value);
}
inline bool ZAddress::is_good_or_null(uintptr_t value) {
// Checking if an address is "not bad" is an optimized version of
// checking if it's "good or null", which eliminates an explicit
// null check. However, the implicit null check only checks that
// the mask bits are zero, not that the entire address is zero.
// This means that an address without mask bits would pass through
// the barrier as if it was null. This should be harmless as such
// addresses should ever be passed through the barrier.
const bool result = !is_bad(value);
assert((is_good(value) || is_null(value)) == result, "Bad address");
return result;
}
inline bool ZAddress::is_weak_bad(uintptr_t value) {
return value & ZAddressWeakBadMask;
}
inline bool ZAddress::is_weak_good(uintptr_t value) {
return !is_weak_bad(value) && !is_null(value);
}
inline bool ZAddress::is_weak_good_or_null(uintptr_t value) {
return !is_weak_bad(value);
}
inline bool ZAddress::is_marked(uintptr_t value) {
return value & ZAddressMetadataMarked;
}
inline bool ZAddress::is_finalizable(uintptr_t value) {
return value & ZAddressMetadataFinalizable;
}
inline bool ZAddress::is_finalizable_good(uintptr_t value) {
return is_finalizable(value) && is_good(value ^ ZAddressMetadataFinalizable);
}
inline bool ZAddress::is_remapped(uintptr_t value) {
return value & ZAddressMetadataRemapped;
}
inline bool ZAddress::is_in(uintptr_t value) {
// Check that exactly one non-offset bit is set
if (!is_power_of_2(value & ~ZAddressOffsetMask)) {
return false;
}
// Check that one of the non-finalizable metadata is set
return value & (ZAddressMetadataMask & ~ZAddressMetadataFinalizable);
}
inline uintptr_t ZAddress::address(uintptr_t value) {
return value | ZAddressBase;
}
inline uintptr_t ZAddress::offset(uintptr_t value) {
return value & ZAddressOffsetMask;
}
inline uintptr_t ZAddress::good(uintptr_t value) {
return address(offset(value) | ZAddressGoodMask);
}
inline uintptr_t ZAddress::good_or_null(uintptr_t value) {
return is_null(value) ? 0 : good(value);
}
inline uintptr_t ZAddress::finalizable_good(uintptr_t value) {
return address(offset(value) | ZAddressMetadataFinalizable | ZAddressGoodMask);
}
inline uintptr_t ZAddress::marked(uintptr_t value) {
return address(offset(value) | ZAddressMetadataMarked);
}
inline uintptr_t ZAddress::marked0(uintptr_t value) {
return address(offset(value) | ZAddressMetadataMarked0);
}
inline uintptr_t ZAddress::marked1(uintptr_t value) {
return address(offset(value) | ZAddressMetadataMarked1);
}
inline uintptr_t ZAddress::remapped(uintptr_t value) {
return address(offset(value) | ZAddressMetadataRemapped);
}
inline uintptr_t ZAddress::remapped_or_null(uintptr_t value) {
return is_null(value) ? 0 : remapped(value);
}
#endif // SHARE_GC_Z_ZADDRESS_INLINE_HPP