public unsafe void TestVectorized()
{
Span <byte> bytes = stackalloc byte[1024];
Span <int> tagStarts = stackalloc int[256];
Span <int> valueStarts = stackalloc int[256];
bytes.Clear();
var byteLen = Encoding.ASCII.GetBytes(msg.AsSpan(), bytes);
Assert.That(byteLen, Is.EqualTo(msg.Length));
var numFields = FixParser.GetFieldBoundariesVectorized(bytes, byteLen, tagStarts, valueStarts);
Assert.That(numFields, Is.EqualTo(8));
Assert.That(tagStarts.Slice(0, numFields).ToArray(), Is.EquivalentTo(new [] { 0, 10, 16, 21, 29, 39, 46, 67 }));
Assert.That(valueStarts.Slice(0, numFields).ToArray(), Is.EquivalentTo(new [] { 2, 12, 19, 24, 32, 42, 49, 70 }));
}
