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<a name="CR16-Operand-Qualifiers"></a>
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<p>
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<hr>
<a name="CR16-Operand-Qualifiers-1"></a>
<h4 class="subsection">9.8.1 CR16 Operand Qualifiers</h4>
<a name="index-CR16-Operand-Qualifiers"></a>

<p>The National Semiconductor CR16 target of <code>as</code> has a few machine dependent operand qualifiers.
</p>
<p>Operand expression type qualifier is an optional field in the instruction operand, to determines the type of the expression field of an operand. The <code>@</code> is required. CR16 architecture uses one of the following expression qualifiers:
</p>
<dl compact="compact">
<dt><code>s</code></dt>
<dd><p>- <code>Specifies expression operand type as small</code>
</p></dd>
<dt><code>m</code></dt>
<dd><p>- <code>Specifies expression operand type as medium</code>
</p></dd>
<dt><code>l</code></dt>
<dd><p>- <code>Specifies expression operand type as large</code>
</p></dd>
<dt><code>c</code></dt>
<dd><p>- <code>Specifies the CR16 Assembler generates a relocation entry for the operand, where pc has implied bit, the expression is adjusted accordingly. The linker uses the relocation entry to update the operand address at link time.</code>
</p></dd>
<dt><code>got/GOT</code></dt>
<dd><p>- <code>Specifies the CR16 Assembler generates a relocation entry for the operand, offset from Global Offset Table. The linker uses this relocation entry to update the operand address at link time</code>
</p></dd>
<dt><code>cgot/cGOT</code></dt>
<dd><p>- <code>Specifies the CompactRISC Assembler generates a relocation entry for the operand, where pc has implied bit, the expression is adjusted accordingly. The linker uses the relocation entry to update the operand address at link time.</code>
</p></dd>
</dl>

<p>CR16 target operand qualifiers and its size (in bits):
</p>
<dl compact="compact">
<dt>&lsquo;<samp>Immediate Operand: s</samp>&rsquo;</dt>
<dd><p>4 bits.
</p>
</dd>
<dt>&lsquo;<samp>Immediate Operand: m</samp>&rsquo;</dt>
<dd><p>16 bits, for movb and movw instructions.
</p>
</dd>
<dt>&lsquo;<samp>Immediate Operand: m</samp>&rsquo;</dt>
<dd><p>20 bits, movd instructions.
</p>
</dd>
<dt>&lsquo;<samp>Immediate Operand: l</samp>&rsquo;</dt>
<dd><p>32 bits.
</p>
</dd>
<dt>&lsquo;<samp>Absolute Operand: s</samp>&rsquo;</dt>
<dd><p>Illegal specifier for this operand.
</p>
</dd>
<dt>&lsquo;<samp>Absolute Operand: m</samp>&rsquo;</dt>
<dd><p>20 bits, movd instructions.
</p>
</dd>
<dt>&lsquo;<samp>Displacement Operand: s</samp>&rsquo;</dt>
<dd><p>8 bits.
</p>
</dd>
<dt>&lsquo;<samp>Displacement Operand: m</samp>&rsquo;</dt>
<dd><p>16 bits.
</p>
</dd>
<dt>&lsquo;<samp>Displacement Operand: l</samp>&rsquo;</dt>
<dd><p>24 bits.
</p>
</dd>
</dl>

<p>For example:
</p><div class="example">
<pre class="example">1   <code>movw $_myfun@c,r1</code>

    This loads the address of _myfun, shifted right by 1, into r1.

2   <code>movd $_myfun@c,(r2,r1)</code>

    This loads the address of _myfun, shifted right by 1, into register-pair r2-r1.

3   <code>_myfun_ptr:</code>
    <code>.long _myfun@c</code>
    <code>loadd _myfun_ptr, (r1,r0)</code>
    <code>jal (r1,r0)</code>

    This .long directive, the address of _myfunc, shifted right by 1 at link time.

4   <code>loadd  _data1@GOT(r12), (r1,r0)</code>

    This loads the address of _data1, into global offset table (ie GOT) and its offset value from GOT loads into register-pair r2-r1.

5   <code>loadd  _myfunc@cGOT(r12), (r1,r0)</code>

    This loads the address of _myfun, shifted right by 1, into global offset table (ie GOT) and its offset value from GOT loads into register-pair r1-r0.
</pre></div>

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