124     uint32_t mask = 0;  in reduce()  local
125     mask |= (exclude.left   > left)   ? 1 : 0;  in reduce()
126     mask |= (exclude.top    > top)    ? 2 : 0;  in reduce()
127     mask |= (exclude.right  < right)  ? 4 : 0;  in reduce()
128     mask |= (exclude.bottom < bottom) ? 8 : 0;  in reduce()
130     if (mask == 0) {  in reduce()
135         if (!(mask & (mask - 1))) {  in reduce()
137             if (mask & 1) {  in reduce()
139             } else if (mask & 2) {  in reduce()
141             } else if (mask & 4) {  in reduce()
143             } else if (mask & 8) {  in reduce()