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toolchain-gcc-arm-embedded

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<a name="CRIS_002dExpand"></a>
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Next: <a href="CRIS_002dSymbols.html#CRIS_002dSymbols" accesskey="n" rel="next">CRIS-Symbols</a>, Previous: <a href="CRIS_002dOpts.html#CRIS_002dOpts" accesskey="p" rel="prev">CRIS-Opts</a>, Up: <a href="CRIS_002dDependent.html#CRIS_002dDependent" accesskey="u" rel="up">CRIS-Dependent</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>
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<a name="Instruction-expansion"></a>
<h4 class="subsection">9.9.2 Instruction expansion</h4>

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<p><code>as</code> will silently choose an instruction that fits
the operand size for &lsquo;<samp>[register+constant]</samp>&rsquo; operands.  For
example, the offset <code>127</code> in <code>move.d [r3+127],r4</code> fits
in an instruction using a signed-byte offset.  Similarly,
<code>move.d [r2+32767],r1</code> will generate an instruction using a
16-bit offset.  For symbolic expressions and constants that do
not fit in 16 bits including the sign bit, a 32-bit offset is
generated.
</p>
<p>For branches, <code>as</code> will expand from a 16-bit branch
instruction into a sequence of instructions that can reach a
full 32-bit address.  Since this does not correspond to a single
instruction, such expansions can optionally be warned about.
See <a href="CRIS_002dOpts.html#CRIS_002dOpts">CRIS-Opts</a>.
</p>
<p>If the operand is found to fit the range, a <code>lapc</code> mnemonic
will translate to a <code>lapcq</code> instruction.  Use <code>lapc.d</code>
to force the 32-bit <code>lapc</code> instruction.
</p>
<p>Similarly, the <code>addo</code> mnemonic will translate to the
shortest fitting instruction of <code>addoq</code>, <code>addo.w</code> and
<code>addo.d</code>, when used with a operand that is a constant known
at assembly time.
</p>


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