static void mkheap_heapify(MKHeap *mkheap, bool doLv0)
{
int i;
MKEntry tmp;
/* Build heap, expanded already at lv 0 */
if(doLv0)
{
for(i=PARENT(mkheap->maxentry); i >= 0; --i)
{
tmp = mkheap->p[i];
mkheap_siftdown(mkheap, i, &tmp);
}
}
/* Populate deeper levels */
while(mke_get_lv(mkheap->p) < mkheap->mkctxt->total_lv - 1)
{
int nlv = mke_get_lv(mkheap->p) + 1;
Assert(nlv < mkheap->mkctxt->total_lv);
mkheap_save_lvtop(mkheap);
mkheap_prep_siftdown_lv(mkheap, nlv, 0, mkheap->mkctxt);
}
#ifdef USE_ASSERT_CHECKING
if(gp_mk_sort_check)
mkheap_verify_heap(mkheap, 0);
#endif
}
/*
* 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);
}
}
/*
* 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;
}