exprSplit
nExpr = exprSplit(ARRAYSIZE(aExpr), aExpr, pWhere);
cnt = 1 + exprSplit(nSlot-1, &aSlot[1], pExpr->pRight);
cnt = exprSplit(nSlot, aSlot, pExpr->pLeft);
cnt += exprSplit(nSlot-cnt, &aSlot[cnt], pExpr->pRight);