as: VAX-branch

1 
1 9.50.5 VAX Branch Improvement
1 -----------------------------
1 
1 Certain pseudo opcodes are permitted.  They are for branch instructions.
1 They expand to the shortest branch instruction that reaches the target.
1 Generally these mnemonics are made by substituting 'j' for 'b' at the
1 start of a DEC mnemonic.  This feature is included both for
1 compatibility and to help compilers.  If you do not need this feature,
1 avoid these opcodes.  Here are the mnemonics, and the code they can
1 expand into.
1 
1 'jbsb'
1      'Jsb' is already an instruction mnemonic, so we chose 'jbsb'.
1      (byte displacement)
1           'bsbb ...'
1      (word displacement)
1           'bsbw ...'
1      (long displacement)
1           'jsb ...'
1 'jbr'
1 'jr'
1      Unconditional branch.
1      (byte displacement)
1           'brb ...'
1      (word displacement)
1           'brw ...'
1      (long displacement)
1           'jmp ...'
1 'jCOND'
1      COND may be any one of the conditional branches 'neq', 'nequ',
1      'eql', 'eqlu', 'gtr', 'geq', 'lss', 'gtru', 'lequ', 'vc', 'vs',
1      'gequ', 'cc', 'lssu', 'cs'.  COND may also be one of the bit tests
1      'bs', 'bc', 'bss', 'bcs', 'bsc', 'bcc', 'bssi', 'bcci', 'lbs',
1      'lbc'.  NOTCOND is the opposite condition to COND.
1      (byte displacement)
1           'bCOND ...'
1      (word displacement)
1           'bNOTCOND foo ; brw ... ; foo:'
1      (long displacement)
1           'bNOTCOND foo ; jmp ... ; foo:'
1 'jacbX'
1      X may be one of 'b d f g h l w'.
1      (word displacement)
1           'OPCODE ...'
1      (long displacement)
1                OPCODE ..., foo ;
1                brb bar ;
1                foo: jmp ... ;
1                bar:
1 'jaobYYY'
1      YYY may be one of 'lss leq'.
1 'jsobZZZ'
1      ZZZ may be one of 'geq gtr'.
1      (byte displacement)
1           'OPCODE ...'
1      (word displacement)
1                OPCODE ..., foo ;
1                brb bar ;
1                foo: brw DESTINATION ;
1                bar:
1      (long displacement)
1                OPCODE ..., foo ;
1                brb bar ;
1                foo: jmp DESTINATION ;
1                bar:
1 'aobleq'
1 'aoblss'
1 'sobgeq'
1 'sobgtr'
1      (byte displacement)
1           'OPCODE ...'
1      (word displacement)
1                OPCODE ..., foo ;
1                brb bar ;
1                foo: brw DESTINATION ;
1                bar:
1      (long displacement)
1                OPCODE ..., foo ;
1                brb bar ;
1                foo: jmp DESTINATION ;
1                bar:
1