@Override
public void evaluate(VectorizedRowBatch batch) {
int n = batch.size;
if (n <= 0) {
return;
}
VectorExpression childExpr1 = this.childExpressions[0];
boolean prevSelectInUse = batch.selectedInUse;
// Save the original selected vector
int[] sel = batch.selected;
if (batch.selectedInUse) {
System.arraycopy(sel, 0, initialSelected, 0, n);
} else {
for (int i = 0; i < n; i++) {
initialSelected[i] = i;
sel[i] = i;
}
batch.selectedInUse = true;
}
childExpr1.evaluate(batch);
// Preserve the selected reference and size values generated
// after the first child is evaluated.
int sizeAfterFirstChild = batch.size;
int[] selectedAfterFirstChild = batch.selected;
// Calculate unselected ones in last evaluate.
for (int j = 0; j < n; j++) {
tmp[initialSelected[j]] = 0;
}
for (int j = 0; j < batch.size; j++) {
tmp[selectedAfterFirstChild[j]] = 1;
}
int unselectedSize = 0;
for (int j = 0; j < n; j++) {
int i = initialSelected[j];
if (tmp[i] == 0) {
unselected[unselectedSize++] = i;
}
}
int newSize = sizeAfterFirstChild;
batch.selected = unselected;
batch.size = unselectedSize;
if (unselectedSize > 0) {
// Evaluate subsequent child expression over unselected ones only.
final int childrenCount = this.childExpressions.length;
int childIndex = 1;
while (true) {
boolean isLastChild = (childIndex + 1 >= childrenCount);
// When we have yet another child beyond the current one... save unselected.
if (!isLastChild) {
System.arraycopy(batch.selected, 0, unselectedCopy, 0, unselectedSize);
}
VectorExpression childExpr = this.childExpressions[childIndex];
childExpr.evaluate(batch);
// Merge the result of last evaluate to previous evaluate.
newSize += batch.size;
for (int i = 0; i < batch.size; i++) {
tmp[batch.selected[i]] = 1;
}
if (isLastChild) {
break;
}
unselectedSize =
subtract(unselectedCopy, unselectedSize, batch.selected, batch.size, difference);
if (unselectedSize == 0) {
break;
}
System.arraycopy(difference, 0, batch.selected, 0, unselectedSize);
batch.size = unselectedSize;
childIndex++;
}
}
// Important: Restore the batch's selected array.
batch.selected = selectedAfterFirstChild;
int k = 0;
for (int j = 0; j < n; j++) {
int i = initialSelected[j];
if (tmp[i] == 1) {
batch.selected[k++] = i;
}
}
batch.size = newSize;
if (newSize == n) {
// Filter didn't do anything
batch.selectedInUse = prevSelectInUse;
}
}
