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<title>Using as: CRIS-Opts</title>

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<a name="CRIS_002dOpts"></a>
<div class="header">
<p>
Next: <a href="CRIS_002dExpand.html#CRIS_002dExpand" accesskey="n" rel="next">CRIS-Expand</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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<hr>
<a name="Command_002dline-Options"></a>
<h4 class="subsection">9.8.1 Command-line Options</h4>

<a name="index-options_002c-CRIS"></a>
<a name="index-CRIS-options"></a>
<p>The CRIS version of <code>as</code> has these
machine-dependent command-line options.
</p>
<a name="index-_002d_002demulation_003dcriself-command-line-option_002c-CRIS"></a>
<a name="index-_002d_002demulation_003dcrisaout-command-line-option_002c-CRIS"></a>
<a name="index-CRIS-_002d_002demulation_003dcriself-command-line-option"></a>
<a name="index-CRIS-_002d_002demulation_003dcrisaout-command-line-option"></a>

<p>The format of the generated object files can be either ELF or
a.out, specified by the command-line options
<samp>--emulation=crisaout</samp> and <samp>--emulation=criself</samp>.
The default is ELF (criself), unless <code>as</code> has been
configured specifically for a.out by using the configuration
name <code>cris-axis-aout</code>.
</p>
<a name="index-_002d_002dunderscore-command-line-option_002c-CRIS"></a>
<a name="index-_002d_002dno_002dunderscore-command-line-option_002c-CRIS"></a>
<a name="index-CRIS-_002d_002dunderscore-command-line-option"></a>
<a name="index-CRIS-_002d_002dno_002dunderscore-command-line-option"></a>
<p>There are two different link-incompatible ELF object file
variants for CRIS, for use in environments where symbols are
expected to be prefixed by a leading &lsquo;<samp>_</samp>&rsquo; character and for
environments without such a symbol prefix.  The variant used for
GNU/Linux port has no symbol prefix.  Which variant to produce
is specified by either of the options <samp>--underscore</samp> and
<samp>--no-underscore</samp>.  The default is <samp>--underscore</samp>.
Since symbols in CRIS a.out objects are expected to have a
&lsquo;<samp>_</samp>&rsquo; prefix, specifying <samp>--no-underscore</samp> when
generating a.out objects is an error.  Besides the object format
difference, the effect of this option is to parse register names
differently (see <a href="CRIS_002dPseudos.html#crisnous">crisnous</a>).  The <samp>--no-underscore</samp>
option makes a &lsquo;<samp>$</samp>&rsquo; register prefix mandatory.
</p>
<a name="index-_002d_002dpic-command-line-option_002c-CRIS"></a>
<a name="index-CRIS-_002d_002dpic-command-line-option"></a>
<a name="index-Position_002dindependent-code_002c-CRIS"></a>
<a name="index-CRIS-position_002dindependent-code"></a>
<p>The option <samp>--pic</samp> must be passed to <code>as</code> in
order to recognize the symbol syntax used for ELF (SVR4 PIC)
position-independent-code (see <a href="CRIS_002dPic.html#crispic">crispic</a>).  This will also
affect expansion of instructions.  The expansion with
<samp>--pic</samp> will use PC-relative rather than (slightly
faster) absolute addresses in those expansions.  This option is only
valid when generating ELF format object files.
</p>
<a name="index-_002d_002dmarch_003darchitecture-command-line-option_002c-CRIS"></a>
<a name="index-CRIS-_002d_002dmarch_003darchitecture-command-line-option"></a>
<a name="index-Architecture-variant-option_002c-CRIS"></a>
<a name="index-CRIS-architecture-variant-option"></a>
<p>The option <samp>--march=<var>architecture</var></samp>
<a name="march_002doption"></a>specifies the recognized instruction set
and recognized register names.  It also controls the
architecture type of the object file.  Valid values for
<var>architecture</var> are:
</p><dl compact="compact">
<dt><code>v0_v10</code></dt>
<dd><p>All instructions and register names for any architecture variant
in the set v0&hellip;v10 are recognized.  This is the
default if the target is configured as cris-*.
</p>
</dd>
<dt><code>v10</code></dt>
<dd><p>Only instructions and register names for CRIS v10 (as found in
ETRAX 100 LX) are recognized.  This is the default if the target
is configured as crisv10-*.
</p>
</dd>
<dt><code>v32</code></dt>
<dd><p>Only instructions and register names for CRIS v32 (code name
Guinness) are recognized.  This is the default if the target is
configured as crisv32-*.  This value implies
<samp>--no-mul-bug-abort</samp>.  (A subsequent
<samp>--mul-bug-abort</samp> will turn it back on.)
</p>
</dd>
<dt><code>common_v10_v32</code></dt>
<dd><p>Only instructions with register names and addressing modes with
opcodes common to the v10 and v32 are recognized.
</p></dd>
</dl>

<a name="index-_002dN-command-line-option_002c-CRIS"></a>
<a name="index-CRIS-_002dN-command-line-option"></a>
<p>When <samp>-N</samp> is specified, <code>as</code> will emit a
warning when a 16-bit branch instruction is expanded into a
32-bit multiple-instruction construct (see <a href="CRIS_002dExpand.html#CRIS_002dExpand">CRIS-Expand</a>).
</p>
<a name="index-_002d_002dno_002dmul_002dbug_002dabort-command-line-option_002c-CRIS"></a>
<a name="index-_002d_002dmul_002dbug_002dabort-command-line-option_002c-CRIS"></a>
<a name="index-CRIS-_002d_002dno_002dmul_002dbug_002dabort-command-line-option"></a>
<a name="index-CRIS-_002d_002dmul_002dbug_002dabort-command-line-option"></a>

<p>Some versions of the CRIS v10, for example in the Etrax 100 LX,
contain a bug that causes destabilizing memory accesses when a
multiply instruction is executed with certain values in the
first operand just before a cache-miss.  When the
<samp>--mul-bug-abort</samp> command line option is active (the
default value), <code>as</code> will refuse to assemble a file
containing a multiply instruction at a dangerous offset, one
that could be the last on a cache-line, or is in a section with
insufficient alignment.  This placement checking does not catch
any case where the multiply instruction is dangerously placed
because it is located in a delay-slot.  The
<samp>--mul-bug-abort</samp> command line option turns off the
checking.
</p>
<hr>
<div class="header">
<p>
Next: <a href="CRIS_002dExpand.html#CRIS_002dExpand" accesskey="n" rel="next">CRIS-Expand</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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