if s.err != nil {
			// Shut it down.
			s.start = 0
			s.end = 0
			return false
		}
		// Must read more data.
		// First, shift data to beginning of buffer if there's lots of empty space
		// or space is needed.
		if s.start > 0 && (s.end == len(s.buf) || s.start > len(s.buf)/2) {
			copy(s.buf, s.buf[s.start:s.end])
			s.end -= s.start
			s.start = 0
		}

import java.io.Serializable;
import java.util.Comparator;
import java.util.List;
import junit.framework.TestCase;
import org.jspecify.annotations.NullUnmarked;

@AndroidIncompatible // lots of failures, possibly some related to bad equals() implementations?
@NullUnmarked
public class TypeTokenSubtypeTest extends TestCase {

  public void testOwnerTypeSubtypes() throws Exception {

    return new ExpiringMemoizingSupplier<>(delegate, toNanosSaturated(duration));
  }

  @VisibleForTesting
  @SuppressWarnings("GoodTime") // lots of violations
  static final class ExpiringMemoizingSupplier<T extends @Nullable Object>
      implements Supplier<T>, Serializable {
    private transient Object lock = new Object();

    final Supplier<T> delegate;

    return new ExpiringMemoizingSupplier<>(delegate, toNanosSaturated(duration));
  }

  @VisibleForTesting
  @SuppressWarnings("GoodTime") // lots of violations
  static final class ExpiringMemoizingSupplier<T extends @Nullable Object>
      implements Supplier<T>, Serializable {
    private transient Object lock = new Object();

    final Supplier<T> delegate;

  /**
   * This is a less carefully-controlled version of {@link #testRemovalNotification_clear} - this is
   * a black-box test that tries to create lots of different thread-interleavings, and asserts that
   * each computation is affected by a call to {@code clear()} (and therefore gets passed to the

  /**
   * This is a less carefully-controlled version of {@link #testRemovalNotification_clear} - this is
   * a black-box test that tries to create lots of different thread-interleavings, and asserts that
   * each computation is affected by a call to {@code clear()} (and therefore gets passed to the

    //     fgha[c]|[b]de -> fgha[b]|[c]de. Because these two blocks are the same size, we are done.
    // The Dolphin algorithm is attractive because it does the fewest array reads and writes: each
    // array slot is read and written exactly once. However, it can have very poor memory locality:
    // benchmarking shows it can take 7 times longer than the other two in some cases. The other two

        // We only ever register ArrayReferences with the queue so this is always safe.
        ArrayReference<? extends L> arrayRef = (ArrayReference<? extends L>) ref;
        // Try to clear out the array slot, n.b. if we fail that is fine, in either case the
        // arrayRef will be out of the array after this step.
        locks.compareAndSet(arrayRef.index, arrayRef, null);
      }
    }

    @Override

* **Computer vision**: an image is composed of millions of pixels, each pixel has 3 values / colors, processing that normally requires computing something on those pixels, all at the same time.
* **Machine Learning**: it normally requires lots of "matrix" and "vector" multiplications. Think of a huge spreadsheet with numbers and multiplying all of them together at the same time.

    if (expected.equals(in)) {
      assertSame(in, out);
    } else {
      assertEquals(expected, out);
    }
  }

  // Test collapse() a little differently than the rest, as we really want to
  // cover lots of different configurations of input text
  public void testCollapse() {
    // collapsing groups of '-' into '_' or '-'
    doTestCollapse("-", "_");
    doTestCollapse("x-", "x_");
    doTestCollapse("-x", "_x");