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<h5 class="subsubsection">9.5.2.3 Relocatable Expression Modifiers</h5>

<p><a name="index-AVR-modifiers-836"></a><a name="index-syntax_002c-AVR-837"></a>
The assembler supports several modifiers when using relocatable addresses
in AVR instruction operands.  The general syntax is the following:

<pre class="smallexample">     modifier(relocatable-expression)
</pre>
     
<a name="index-symbol-modifiers-838"></a>
<dl>
<dt><code>lo8</code><dd>
This modifier allows you to use bits 0 through 7 of
an address expression as 8 bit relocatable expression.

     <br><dt><code>hi8</code><dd>
This modifier allows you to use bits 7 through 15 of an address expression
as 8 bit relocatable expression.  This is useful with, for example, the
AVR &lsquo;<samp><span class="samp">ldi</span></samp>&rsquo; instruction and &lsquo;<samp><span class="samp">lo8</span></samp>&rsquo; modifier.

     <p>For example

     <pre class="smallexample">          ldi r26, lo8(sym+10)
          ldi r27, hi8(sym+10)
</pre>
     <br><dt><code>hh8</code><dd>
This modifier allows you to use bits 16 through 23 of
an address expression as 8 bit relocatable expression. 
Also, can be useful for loading 32 bit constants.

     <br><dt><code>hlo8</code><dd>
Synonym of &lsquo;<samp><span class="samp">hh8</span></samp>&rsquo;.

     <br><dt><code>hhi8</code><dd>
This modifier allows you to use bits 24 through 31 of
an expression as 8 bit expression. This is useful with, for example, the
AVR &lsquo;<samp><span class="samp">ldi</span></samp>&rsquo; instruction and &lsquo;<samp><span class="samp">lo8</span></samp>&rsquo;, &lsquo;<samp><span class="samp">hi8</span></samp>&rsquo;, &lsquo;<samp><span class="samp">hlo8</span></samp>&rsquo;,
&lsquo;<samp><span class="samp">hhi8</span></samp>&rsquo;, modifier.

     <p>For example

     <pre class="smallexample">          ldi r26, lo8(285774925)
          ldi r27, hi8(285774925)
          ldi r28, hlo8(285774925)
          ldi r29, hhi8(285774925)
          ; r29,r28,r27,r26 = 285774925
</pre>
     <br><dt><code>pm_lo8</code><dd>
This modifier allows you to use bits 0 through 7 of
an address expression as 8 bit relocatable expression. 
This modifier useful for addressing data or code from
Flash/Program memory. The using of &lsquo;<samp><span class="samp">pm_lo8</span></samp>&rsquo; similar
to &lsquo;<samp><span class="samp">lo8</span></samp>&rsquo;.

     <br><dt><code>pm_hi8</code><dd>
This modifier allows you to use bits 8 through 15 of
an address expression as 8 bit relocatable expression. 
This modifier useful for addressing data or code from
Flash/Program memory.

     <br><dt><code>pm_hh8</code><dd>
This modifier allows you to use bits 15 through 23 of
an address expression as 8 bit relocatable expression. 
This modifier useful for addressing data or code from
Flash/Program memory.

   </dl>

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