8198515: Extract SoftReferencePolicy code out of CollectorPolicy
Reviewed-by: pliden, sjohanss
/*
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* DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
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* 2 along with this work; if not, write to the Free Software Foundation,
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#ifndef SHARE_VM_GC_SHARED_BARRIERSET_INLINE_HPP
#define SHARE_VM_GC_SHARED_BARRIERSET_INLINE_HPP
#include "gc/shared/barrierSet.hpp"
#include "gc/shared/barrierSetConfig.inline.hpp"
#include "utilities/align.hpp"
// count is number of array elements being written
void BarrierSet::write_ref_array(HeapWord* start, size_t count) {
assert(count <= (size_t)max_intx, "count too large");
HeapWord* end = (HeapWord*)((char*)start + (count*heapOopSize));
// In the case of compressed oops, start and end may potentially be misaligned;
// so we need to conservatively align the first downward (this is not
// strictly necessary for current uses, but a case of good hygiene and,
// if you will, aesthetics) and the second upward (this is essential for
// current uses) to a HeapWord boundary, so we mark all cards overlapping
// this write. If this evolves in the future to calling a
// logging barrier of narrow oop granularity, like the pre-barrier for G1
// (mentioned here merely by way of example), we will need to change this
// interface, so it is "exactly precise" (if i may be allowed the adverbial
// redundancy for emphasis) and does not include narrow oop slots not
// included in the original write interval.
HeapWord* aligned_start = align_down(start, HeapWordSize);
HeapWord* aligned_end = align_up (end, HeapWordSize);
// If compressed oops were not being used, these should already be aligned
assert(UseCompressedOops || (aligned_start == start && aligned_end == end),
"Expected heap word alignment of start and end");
write_ref_array_work(MemRegion(aligned_start, aligned_end));
}
#endif // SHARE_VM_GC_SHARED_BARRIERSET_INLINE_HPP