/*
* Prepare heap (expand lv) at postion cur.
*/
static void
mkheap_prep_siftdown_lv(MKHeap *mkheap, int lv, int cur, MKContext *mkctxt)
{
bool expchild = false;
int c;
Assert(cur < mkheap->maxentry);
Assert(cur >= 0);
/* If necessary, expand right */
if (RIGHT(cur) < mkheap->maxentry)
{
c = mkheap_compare(mkheap, mkheap->p + cur, mkheap->p + RIGHT(cur));
if (c == 0)
{
mkheap_prep_siftdown_lv(mkheap, lv, RIGHT(cur), mkctxt);
expchild = true;
}
}
/* If necessary, expand left */
if (LEFT(cur) < mkheap->maxentry)
{
c = mkheap_compare(mkheap, mkheap->p + cur, mkheap->p + LEFT(cur));
if (c == 0)
{
mkheap_prep_siftdown_lv(mkheap, lv, LEFT(cur), mkctxt);
expchild = true;
}
}
Assert(mke_get_lv(mkheap->p + cur) == lv - 1);
if (mkheap->mkctxt->fetchForPrep)
tupsort_prepare(mkheap->p + cur, mkctxt, lv);
mke_set_lv(mkheap->p + cur, lv);
if (expchild)
{
MKEntry tmp = mkheap->p[cur];
mkheap_siftdown(mkheap, cur, &tmp);
}
}
/*
* Update all lvtops entries. The lvtops entries whose array index is not greater
* than the level value stored in the current top element in the heap, update them
* with the value from the top element in the heap. This function also cleans up
* the remaining lvtops entries.
*
* This is needed after the current top entry in the heap is removed from the heap, since
* some lvtops' ptr may point to the tuple that could be freed when its associated entry
* is removed from the heap.
*/
static void mkheap_update_lvtops(MKHeap *mkheap)
{
int top_lv = mke_get_lv(mkheap->p);
for (int lv = 0; lv < mkheap->mkctxt->total_lv; lv++)
{
MKEntry *lvEntry = mkheap->lvtops + lv;
MKEntry *srcEntry = NULL;
if (lv <= top_lv)
{
srcEntry = mkheap->p;
if ( mkheap->mkctxt->fetchForPrep)
tupsort_prepare(mkheap->p, mkheap->mkctxt, lv);
}
(*mkheap->mkctxt->cpfr)(lvEntry, srcEntry, mkheap->mkctxt->lvctxt + lv);
/* Set the correct level */
mke_set_lv(lvEntry, lv);
}
}
void mkheap_verify_heap(MKHeap *heap, int top)
{
int empty_cnt = 0;
int i;
MKEntry e;
if(heap->count == 0)
return;
Assert(heap->count > 0);
Assert(heap->maxentry > 0);
Assert(heap->count <= heap->maxentry);
Assert(heap->maxentry <= heap->alloc_size);
e = heap->p[0];
mke_set_lv(&e, 0);
mke_clear_refc_copied(&e);
/* Checking for lvtops */
for(i=0; i<mke_get_lv(heap->p); ++i)
{
int c;
/* Too much trouble dealing with ref counters. Just don't */
/*
if(!mke_test_flag(heap->lvtops+i, MKE_RefCnt | MKE_Copied))
{
*/
mke_set_lv(&e, i);
if ( heap->mkctxt->fetchForPrep)
tupsort_prepare(&e, heap->mkctxt, i);
c = mkheap_compare(heap, &e, heap->lvtops+i);
Assert(c==0);
/*
}
*/
}
/* Verify Heap property */
for(i=top; i<heap->maxentry; ++i)
{
int left = LEFT(i);
int right = RIGHT(i);
int cl, cr;
if(mke_is_empty(heap->p+i))
++empty_cnt;
if(left >= heap->maxentry)
continue;
cl = mkheap_compare(heap, heap->p+i, heap->p+left);
Assert(cl<=0);
if(i==0 && cl==0)
Assert(mke_get_lv(heap->p) == heap->mkctxt->total_lv-1);
if(right >= heap->maxentry)
continue;
cr = mkheap_compare(heap, heap->p+i, heap->p+right);
Assert(cr<=0);
if(i==0 && cr==0)
Assert(mke_get_lv(heap->p) == heap->mkctxt->total_lv-1);
}
}
/*
* Insert an entry and perhaps return the top element of the heap in *e
*
* Comparison happens from the specified level to the end of levels, as needed:
* Return < 0 if smaller than heap top; *e is unchanged
* Return = 0 if eq to heap top ; *e is unchanged (but will have value equal to the heap top)
* Return > 0 if successfully inserted; *e is populated with the removed heap top
*
* If 0 would be returned but the heap is marked as needing uniqueness enforcement, error is generated instead
*/
static int mkheap_putAndGet_impl(MKHeap *mkheap, MKEntry *e)
{
int c = 0;
int toplv;
MKEntry tmp;
/* can't put+get from an empty heap */
Assert(mkheap->count > 0);
if ( mkheap->mkctxt->enforceUnique &&
mke_has_duplicates_with_root(mkheap))
{
/**
* See NOTE ON UNIQUENESS CHECKING in the comment at the top of the file
* for information about why we check for duplicates here
*/
ERROR_UNIQUENESS_VIOLATED();
}
if(mke_is_empty(e))
{
/* adding an empty (sentinel): just remove from count and fallthrough to where top is removed */
--mkheap->count;
}
else if (mke_get_run(e) != mke_get_run(mkheap->p))
{
/* this code assumes that the new one, with lower run, is LARGER than the top -- so it must be larger run */
Assert(mke_get_run(e) > mke_get_run(mkheap->p));
/* when the runs differ it is because we attempted once with the runs equal.
* So if level is zero then: the level was zero AND validly prepared for the previous run -- and there is no need to prep again
*/
if ( mke_get_lv(e) != 0 )
{
/* Not same run, at least prepare lv 0 */
if ( mkheap->mkctxt->fetchForPrep)
tupsort_prepare(e, mkheap->mkctxt, 0);
mke_set_lv(e, 0);
}
/* now fall through and let top be returned, new one is also inserted so no change to count */
}
else
{
/* same run so figure out where it fits in relation to the heap top */
int lv = 0;
toplv = mke_get_lv(mkheap->p);
mke_set_lv(e, lv);
/* populate level until we differ from the top element of the heap */
while (lv < toplv)
{
if ( mkheap->mkctxt->fetchForPrep)
tupsort_prepare(e, mkheap->mkctxt, lv);
c = mkheap_compare(mkheap, e, mkheap->lvtops+lv);
if(c!=0)
break;
mke_set_lv(e, ++lv);
}
/* smaller than top */
if(c<0)
return -1;
/* we have not done e->lv == toplv yet since we increment at the end of the previous loop. Do it now. */
Assert(mke_get_lv(e) == lv);
if(lv == toplv)
{
if ( mkheap->mkctxt->fetchForPrep)
tupsort_prepare(e, mkheap->mkctxt, lv);
c = mkheap_compare(mkheap, e, mkheap->p);
if(c < 0)
return -1;
}
if(c==0)
{
/*
* Equal and at top level.
*
* This means that e is less-than/equal to all entries except the heap top.
*/
Assert(mke_get_lv(e) == lv);
Assert(lv == mke_get_lv(mkheap->p));
/*
* Expand more levels of lvtop in the current top and the new one until we detect a difference.
*/
while(lv < mkheap->mkctxt->total_lv - 1)
{
mkheap_save_lvtop(mkheap);
++lv;
/* expand top */
if ( mkheap->mkctxt->fetchForPrep)
tupsort_prepare(mkheap->p, mkheap->mkctxt, lv);
/* expand new element */
if ( mkheap->mkctxt->fetchForPrep)
tupsort_prepare(e, mkheap->mkctxt, lv);
mke_set_lv(mkheap->p, lv);
mke_set_lv(e, lv);
c = mkheap_compare(mkheap, e, mkheap->p);
if(c != 0)
break;
}
if(c<=0)
{
/* if new one is less than current top then we just return that negative comparison */
/* if new one equals the current top then we could do an insert and immediate removal -- but it
* won't matter so we simply return right away, leaving *e untouched */
/* enforce uniqueness first */
if(c == 0 && mkheap->mkctxt->enforceUnique)
{
ERROR_UNIQUENESS_VIOLATED();
}
return c;
}
}
}
/* Now, I am bigger than top but not definitely smaller/equal to all other entries
*
* So we will:
* return top as *e
* do heap shuffling to restore heap ordering
*/
tmp = *e;
*e = mkheap->p[0];
/* Sift down a hole to bottom of (current or next) run, depends on tmp.run */
mkheap_siftdown(mkheap, 0, &tmp);
if(mkheap_need_heapify(mkheap))
mkheap_heapify(mkheap, false);
if (mkheap->count > 0)
{
mkheap_update_lvtops(mkheap);
}
#ifdef USE_ASSERT_CHECKING
if(gp_mk_sort_check)
mkheap_verify_heap(mkheap, 0);
#endif
return 1;
}