Description

   The .SYMBOL_ALIGNMENT directive is used to associate an alignment
   attribute with the fields in a structure when you know the base
   alignment. It is used in pairs. The first .SYMBOL_ALIGNMENT
   directive associates either longword (long) or quadword (quad)
   alignment with the symbol or symbols that follow. The second
   directive, .SYMBOL_ALIGNMENT none, turns it off.

   Any time a reference is made with a symbol with an alignment
   attribute, the base register of that reference, in effect,
   inherits the symbol's alignment. The compiler also resets the
   base register's alignment to longword for subsequent alignment
   tracking. This alignment guarantee enables the compiler to
   produce more efficient code sequences.