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 <a name="M68HC11_002dBranch"></a>
 <div class="header">
 <p>
 Up: <a href="M68HC11_002dopcodes.html#M68HC11_002dopcodes" accesskey="u" rel="up">M68HC11-opcodes</a> &nbsp; [<a href="index.html#SEC_Contents" title="Table of contents" rel="contents">Contents</a>][<a href="AS-Index.html#AS-Index" title="Index" rel="index">Index</a>]</p>
 </div>
 <hr>
 <a name="Branch-Improvement-1"></a>
 <h4 class="subsubsection">9.24.6.1 Branch Improvement</h4>

 <a name="index-pseudo_002dopcodes_002c-M68HC11"></a>
 <a name="index-M68HC11-pseudo_002dopcodes"></a>
 <a name="index-branch-improvement_002c-M68HC11"></a>
 <a name="index-M68HC11-branch-improvement"></a>

 <p>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 &lsquo;<samp>j</samp>&rsquo; to
 the start of Motorola mnemonic. These pseudo opcodes are not affected
 by the &lsquo;<samp>--short-branches</samp>&rsquo; or &lsquo;<samp>--force-long-branches</samp>&rsquo; options.
 </p>
 <p>The following table summarizes the pseudo-operations.
 </p>
 <div class="smallexample">
 <pre class="smallexample">                        Displacement Width
      +-------------------------------------------------------------+
      |                     Options                                 |
      |    --short-branches           --force-long-branches         |
      +--------------------------+----------------------------------+
   Op |BYTE             WORD     | BYTE          WORD               |
      +--------------------------+----------------------------------+
  bsr | bsr &lt;pc-rel&gt;    &lt;error&gt;  |               jsr &lt;abs&gt;          |
  bra | bra &lt;pc-rel&gt;    &lt;error&gt;  |               jmp &lt;abs&gt;          |
 jbsr | bsr &lt;pc-rel&gt;   jsr &lt;abs&gt; | bsr &lt;pc-rel&gt;  jsr &lt;abs&gt;          |
 jbra | bra &lt;pc-rel&gt;   jmp &lt;abs&gt; | bra &lt;pc-rel&gt;  jmp &lt;abs&gt;          |
  bXX | bXX &lt;pc-rel&gt;    &lt;error&gt;  |               bNX +3; jmp &lt;abs&gt;  |
 jbXX | bXX &lt;pc-rel&gt;   bNX +3;   | bXX &lt;pc-rel&gt;  bNX +3; jmp &lt;abs&gt;  |
      |                jmp &lt;abs&gt; |                                  |
      +--------------------------+----------------------------------+
 XX: condition
 NX: negative of condition XX

 </pre></div>

 <dl compact="compact">
 <dt><code>jbsr</code></dt>
 <dt><code>jbra</code></dt>
 <dd><p>These are the simplest jump pseudo-operations; they always map to one
 particular machine instruction, depending on the displacement to the
 branch target.
 </p>
 </dd>
 <dt><code>jb<var>XX</var></code></dt>
 <dd><p>Here, &lsquo;<samp>jb<var>XX</var></samp>&rsquo; stands for an entire family of pseudo-operations,
 where <var>XX</var> is a conditional branch or condition-code test.  The full
 list of pseudo-ops in this family is:
 </p><div class="smallexample">
 <pre class="smallexample"> jbcc   jbeq   jbge   jbgt   jbhi   jbvs   jbpl  jblo
  jbcs   jbne   jblt   jble   jbls   jbvc   jbmi
 </pre></div>

 <p>For the cases of non-PC relative displacements and long displacements,
 <code>as</code> issues a longer code fragment in terms of
 <var>NX</var>, the opposite condition to <var>XX</var>.  For example, for the
 non-PC relative case:
 </p><div class="smallexample">
 <pre class="smallexample">    jb<var>XX</var> foo
 </pre></div>
 <p>gives
 </p><div class="smallexample">
 <pre class="smallexample">     b<var>NX</var>s oof
      jmp foo
  oof:
 </pre></div>

 </dd>
 </dl>


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	<a name="M68HC11_002dBranch"></a>
	<div class="header">
	<p>
	Up: <a href="M68HC11_002dopcodes.html#M68HC11_002dopcodes" accesskey="u" rel="up">M68HC11-opcodes</a>   [<a href="index.html#SEC_Contents" title="Table of contents" rel="contents">Contents</a>][<a href="AS-Index.html#AS-Index" title="Index" rel="index">Index</a>]</p>
	</div>
	<hr>
	<a name="Branch-Improvement-1"></a>
	<h4 class="subsubsection">9.24.6.1 Branch Improvement</h4>

	<a name="index-pseudo_002dopcodes_002c-M68HC11"></a>
	<a name="index-M68HC11-pseudo_002dopcodes"></a>
	<a name="index-branch-improvement_002c-M68HC11"></a>
	<a name="index-M68HC11-branch-improvement"></a>

	<p>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 ‘<samp>j</samp>’ to
	the start of Motorola mnemonic. These pseudo opcodes are not affected
	by the ‘<samp>--short-branches</samp>’ or ‘<samp>--force-long-branches</samp>’ options.
	</p>
	<p>The following table summarizes the pseudo-operations.
	</p>
	<div class="smallexample">
	<pre class="smallexample"> Displacement Width
	+-------------------------------------------------------------+
	\| Options \|
	\| --short-branches --force-long-branches \|
	+--------------------------+----------------------------------+
	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

	</pre></div>

	<dl compact="compact">
	<dt><code>jbsr</code></dt>
	<dt><code>jbra</code></dt>
	<dd><p>These are the simplest jump pseudo-operations; they always map to one
	particular machine instruction, depending on the displacement to the
	branch target.
	</p>
	</dd>
	<dt><code>jb<var>XX</var></code></dt>
	<dd><p>Here, ‘<samp>jb<var>XX</var></samp>’ stands for an entire family of pseudo-operations,
	where <var>XX</var> is a conditional branch or condition-code test. The full
	list of pseudo-ops in this family is:
	</p><div class="smallexample">
	<pre class="smallexample"> jbcc jbeq jbge jbgt jbhi jbvs jbpl jblo
	jbcs jbne jblt jble jbls jbvc jbmi
	</pre></div>

	<p>For the cases of non-PC relative displacements and long displacements,
	<code>as</code> issues a longer code fragment in terms of
	<var>NX</var>, the opposite condition to <var>XX</var>. For example, for the
	non-PC relative case:
	</p><div class="smallexample">
	<pre class="smallexample"> jb<var>XX</var> foo
	</pre></div>
	<p>gives
	</p><div class="smallexample">
	<pre class="smallexample"> b<var>NX</var>s oof
	jmp foo
	oof:
	</pre></div>

	</dd>
	</dl>







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