objectStartArray.inline.hpp

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#ifndef SHARE_GC_PARALLEL_OBJECTSTARTARRAY_INLINE_HPP
#define SHARE_GC_PARALLEL_OBJECTSTARTARRAY_INLINE_HPP

#include "gc/parallel/objectStartArray.hpp"

// Optimized for finding the first object that crosses into
// a given block. The blocks contain the offset of the last
// object in that block. Scroll backwards by one, and the first
// object hit should be at the beginning of the block
HeapWord* ObjectStartArray::object_start(HeapWord* addr) const {
  assert_covered_region_contains(addr);
  jbyte* block = block_for_addr(addr);
  HeapWord* scroll_forward = offset_addr_for_block(block--);
  while (scroll_forward > addr) {
    scroll_forward = offset_addr_for_block(block--);
  }

  HeapWord* next = scroll_forward;
  while (next <= addr) {
    scroll_forward = next;
    next += cast_to_oop(next)->size();
  }
  assert(scroll_forward <= addr, "wrong order for current and arg");
  assert(addr <= next, "wrong order for arg and next");
  return scroll_forward;
}


#endif // SHARE_GC_PARALLEL_OBJECTSTARTARRAY_INLINE_HPP