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<h5 class="subsubsection">9.21.2.1 Symbolic Operand Modifiers</h5>
<p><a name="index-M32C-modifiers-1275"></a><a name="index-modifiers_002c-M32C-1276"></a>
The assembler supports several modifiers when using symbol addresses
in M32C instruction operands. The general syntax is the following:
<pre class="smallexample"> %modifier(symbol)
</pre>
<a name="index-symbol-modifiers-1277"></a>
<dl>
<dt><code>%dsp8</code><dt><code>%dsp16</code><dd>
These modifiers override the assembler's assumptions about how big a
symbol's address is. Normally, when it sees an operand like
‘<samp><span class="samp">sym[a0]</span></samp>’ it assumes ‘<samp><span class="samp">sym</span></samp>’ may require the widest
displacement field (16 bits for ‘<samp><span class="samp">-m16c</span></samp>’, 24 bits for
‘<samp><span class="samp">-m32c</span></samp>’). These modifiers tell it to assume the address will fit
in an 8 or 16 bit (respectively) unsigned displacement. Note that, of
course, if it doesn't actually fit you will get linker errors. Example:
<pre class="smallexample"> mov.w %dsp8(sym)[a0],r1
mov.b #0,%dsp8(sym)[a0]
</pre>
<br><dt><code>%hi8</code><dd>
This modifier allows you to load bits 16 through 23 of a 24 bit
address into an 8 bit register. This is useful with, for example, the
M16C ‘<samp><span class="samp">smovf</span></samp>’ instruction, which expects a 20 bit address in
‘<samp><span class="samp">r1h</span></samp>’ and ‘<samp><span class="samp">a0</span></samp>’. Example:
<pre class="smallexample"> mov.b #%hi8(sym),r1h
mov.w #%lo16(sym),a0
smovf.b
</pre>
<br><dt><code>%lo16</code><dd>
Likewise, this modifier allows you to load bits 0 through 15 of a 24
bit address into a 16 bit register.
<br><dt><code>%hi16</code><dd>
This modifier allows you to load bits 16 through 31 of a 32 bit
address into a 16 bit register. While the M32C family only has 24
bits of address space, it does support addresses in pairs of 16 bit
registers (like ‘<samp><span class="samp">a1a0</span></samp>’ for the ‘<samp><span class="samp">lde</span></samp>’ instruction). This
modifier is for loading the upper half in such cases. Example:
<pre class="smallexample"> mov.w #%hi16(sym),a1
mov.w #%lo16(sym),a0
...
lde.w [a1a0],r1
</pre>
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