VMS Help MACRO, VAX MACRO Assembler, Instructions, INSQUE  *Conan The Librarian (sorry for the slow response - running on an old VAX)

    Purpose:        Add entry to head or tail of queue
    Format:         opcode entry.ab,pred.ab
    Operation:      if {all memory accesses can be completed} then
                    begin
                      (entry) = (pred);             ;forward link
                      (entry+4) = pred;             ;backward link
                      ((pred)+4) = entry;           ;backward successor
                      (pred) = entry;               ;forward predessor
                    end;
                    else
                    begin
                      {backup instruction};
                      {initiate fault};
                    end;
    C. Codes:       N = {(entry) LSS (entry + 4)}, V = 0,
                    C = {(entry) LSSU (entry + 4)},
                    Z = {(entry) EQL (entry + 4)}
    Exceptions:     None
    Opcode:         0E    INSQUE   Insert entry in queue
    Description:    The queue entry specified by the operand entry is
                    inserted into the queue following the entry
                    specified by pred. If the entry inserted is the
                    first one in the queue, the Z bit is set; otherwise
                    it is cleared. The insertion is a noninterruptable
                    operation. The entire operation is validated before
                    any portion of it is attempted. The queue will be
                    left in a consistent state if a memory management
                    violation occurs.