1 /*
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 3  * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
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24 
25 #ifndef SHARE_VM_GC_SHARED_BARRIERSET_INLINE_HPP
26 #define SHARE_VM_GC_SHARED_BARRIERSET_INLINE_HPP
27 
28 #include "gc/shared/barrierSet.hpp"
29 #include "gc/shared/barrierSetConfig.inline.hpp"
30 #include "utilities/align.hpp"
31 
32 // count is number of array elements being written
33 void BarrierSet::write_ref_array(HeapWord* start, size_t count) {
34   assert(count <= (size_t)max_intx, "count too large");
35   HeapWord* end = (HeapWord*)((char*)start + (count*heapOopSize));
36   // In the case of compressed oops, start and end may potentially be misaligned;
37   // so we need to conservatively align the first downward (this is not
38   // strictly necessary for current uses, but a case of good hygiene and,
39   // if you will, aesthetics) and the second upward (this is essential for
40   // current uses) to a HeapWord boundary, so we mark all cards overlapping
41   // this write. If this evolves in the future to calling a
42   // logging barrier of narrow oop granularity, like the pre-barrier for G1
43   // (mentioned here merely by way of example), we will need to change this
44   // interface, so it is "exactly precise" (if i may be allowed the adverbial
45   // redundancy for emphasis) and does not include narrow oop slots not
46   // included in the original write interval.
47   HeapWord* aligned_start = align_down(start, HeapWordSize);
48   HeapWord* aligned_end   = align_up  (end,   HeapWordSize);
49   // If compressed oops were not being used, these should already be aligned
50   assert(UseCompressedOops || (aligned_start == start && aligned_end == end),
51          "Expected heap word alignment of start and end");
52   write_ref_array_work(MemRegion(aligned_start, aligned_end));
53 }
54 
55 inline void BarrierSet::write_region(MemRegion mr) {
56   write_region_work(mr);
57 }
58 
59 #endif // SHARE_VM_GC_SHARED_BARRIERSET_INLINE_HPP