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Up: M68HC11-opcodes

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Branch Improvement
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   Certain pseudo opcodes are permitted for branch instructions.  They
expand to the shortest branch instruction that reach the target.
Generally these mnemonics are made by prepending `j' to the start of
Motorola mnemonic. These pseudo opcodes are not affected by the
`--short-branchs' or `--force-long-branchs' options.

   The following table summarizes the pseudo-operations.

                                   Displacement Width
               +-------------------------------------------------------------+
               |                     Options                                 |
               |    --short-branchs            --force-long-branchs          |
               +--------------------------+----------------------------------+
     Pseudo-Op |BYTE             WORD     | BYTE          WORD               |
               +--------------------------+----------------------------------+
           bsr | bsr <pc-rel>    <error>  |               jsr <abs>          |
           bra | bra <pc-rel>    <error>  |               jmp <abs>          |
          jbsr | bsr <pc-rel>   jsr <abs> | bsr <pc-rel>  jsr <abs>          |
          jbra | bra <pc-rel>   jmp <abs> | bra <pc-rel>  jmp <abs>          |
           bXX | bXX <pc-rel>    <error>  |               bNX +3; jmp <abs>  |
          jbXX | bXX <pc-rel>   bNX +3;   | bXX <pc-rel>  bNX +3; jmp <abs>  |
               |                jmp <abs> |                                  |
               +--------------------------+----------------------------------+
     XX: condition
     NX: negative of condition XX

`jbsr'
`jbra'
     These are the simplest jump pseudo-operations; they always map to
     one particular machine instruction, depending on the displacement
     to the branch target.

`jbXX'
     Here, `jbXX' stands for an entire family of pseudo-operations,
     where XX is a conditional branch or condition-code test.  The full
     list of pseudo-ops in this family is:
           jbcc   jbeq   jbge   jbgt   jbhi   jbvs   jbpl  jblo
           jbcs   jbne   jblt   jble   jbls   jbvc   jbmi

     For the cases of non-PC relative displacements and long
     displacements, `as' issues a longer code fragment in terms of NX,
     the opposite condition to XX.  For example, for the non-PC
     relative case:
              jbXX foo
     gives
               bNXs oof
               jmp foo
           oof: