113     uint32_t mask = 0;  in reduce()  local
114     mask |= (exclude.left   > left)   ? 1 : 0;  in reduce()
115     mask |= (exclude.top    > top)    ? 2 : 0;  in reduce()
116     mask |= (exclude.right  < right)  ? 4 : 0;  in reduce()
117     mask |= (exclude.bottom < bottom) ? 8 : 0;  in reduce()
119     if (mask == 0) {  in reduce()
124         if (!(mask & (mask - 1))) {  in reduce()
126             if (mask & 1) {  in reduce()
128             } else if (mask & 2) {  in reduce()
130             } else if (mask & 4) {  in reduce()
132             } else if (mask & 8) {  in reduce()