as: M68K-Syntax

1 
1 9.23.2 Syntax
1 -------------
1 
1 This syntax for the Motorola 680x0 was developed at MIT.
1 
1    The 680x0 version of 'as' uses instructions names and syntax
1 compatible with the Sun assembler.  Intervening periods are ignored; for
1 example, 'movl' is equivalent to 'mov.l'.
1 
1    In the following table APC stands for any of the address registers
1 ('%a0' through '%a7'), the program counter ('%pc'), the zero-address
1 relative to the program counter ('%zpc'), a suppressed address register
1 ('%za0' through '%za7'), or it may be omitted entirely.  The use of SIZE
1 means one of 'w' or 'l', and it may be omitted, along with the leading
1 colon, unless a scale is also specified.  The use of SCALE means one of
1 '1', '2', '4', or '8', and it may always be omitted along with the
1 leading colon.
1 
1    The following addressing modes are understood:
1 "Immediate"
1      '#NUMBER'
1 
1 "Data Register"
1      '%d0' through '%d7'
1 
1 "Address Register"
1      '%a0' through '%a7'
1      '%a7' is also known as '%sp', i.e., the Stack Pointer.  '%a6' is
1      also known as '%fp', the Frame Pointer.
1 
1 "Address Register Indirect"
1      '%a0@' through '%a7@'
1 
1 "Address Register Postincrement"
1      '%a0@+' through '%a7@+'
1 
1 "Address Register Predecrement"
1      '%a0@-' through '%a7@-'
1 
1 "Indirect Plus Offset"
1      'APC@(NUMBER)'
1 
1 "Index"
1      'APC@(NUMBER,REGISTER:SIZE:SCALE)'
1 
1      The NUMBER may be omitted.
1 
1 "Postindex"
1      'APC@(NUMBER)@(ONUMBER,REGISTER:SIZE:SCALE)'
1 
1      The ONUMBER or the REGISTER, but not both, may be omitted.
1 
1 "Preindex"
1      'APC@(NUMBER,REGISTER:SIZE:SCALE)@(ONUMBER)'
1 
1      The NUMBER may be omitted.  Omitting the REGISTER produces the
1      Postindex addressing mode.
1 
1 "Absolute"
1      'SYMBOL', or 'DIGITS', optionally followed by ':b', ':w', or ':l'.
1