let summary = "Computes and applies all necessary control dependencies based on side effect analysis.";
  let description = [{
    This pass is intended to run after the split_into_island_per_op
    pass. That pass splits up multi-op islands into multiple individual islands
    wrapping a single op without applying any control deps between the new
    islands. So, this pass is needed in order to make preservation of the

	// clang says "unknown argument".
	// tcc says "unsupported"
	// AIX says "not recognized"
	// Older versions of GCC say "unrecognised debug output level".
	// For -fsplit-stack GCC says "'-fsplit-stack' is not supported".
	supported := !bytes.Contains(out, []byte("unrecognized")) &&
		!bytes.Contains(out, []byte("unknown")) &&
		!bytes.Contains(out, []byte("unrecognised")) &&

		return
	}

	// if already replicated, return true if a new reset was requested.
	splits := strings.SplitN(rs, ";", 2)
	if len(splits) != 2 {
		return
	}
	newReset := splits[1] != resetID
	if !newReset && tgtStatus == replication.Completed {
		// already replicated and no reset requested
		return
	}

	writeStatusLine(w.conn.bufw, w.req.ProtoAtLeast(1, 1), code, w.statusBuf[:])
	cw.header.WriteSubset(w.conn.bufw, excludeHeader)
	setHeader.Write(w.conn.bufw)
	w.conn.bufw.Write(crlf)
}

// foreachHeaderElement splits v according to the "#rule" construction
// in RFC 7230 section 7 and calls fn for each non-empty element.
func foreachHeaderElement(v string, fn func(string)) {
	v = textproto.TrimString(v)
	if v == "" {
		return