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<a name="CRIS_002dOpts"></a>Next:&nbsp;<a rel="next" accesskey="n" href="CRIS_002dExpand.html#CRIS_002dExpand">CRIS-Expand</a>,
Up:&nbsp;<a rel="up" accesskey="u" href="CRIS_002dDependent.html#CRIS_002dDependent">CRIS-Dependent</a>
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<h4 class="subsection">9.7.1 Command-line Options</h4>
<p><a name="index-options_002c-CRIS-669"></a><a name="index-CRIS-options-670"></a>The CRIS version of <code>as</code> has these
machine-dependent command-line options.
<p><a name="index-_0040option_007b_002d_002demulation_003dcriself_007d-command-line-option_002c-CRIS-671"></a><a name="index-_0040option_007b_002d_002demulation_003dcrisaout_007d-command-line-option_002c-CRIS-672"></a><a name="index-CRIS-_0040option_007b_002d_002demulation_003dcriself_007d-command-line-option-673"></a><a name="index-CRIS-_0040option_007b_002d_002demulation_003dcrisaout_007d-command-line-option-674"></a>
The format of the generated object files can be either ELF or
a.out, specified by the command-line options
<span class="option">--emulation=crisaout</span> and <span class="option">--emulation=criself</span>.
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-_0040option_007b_002d_002dunderscore_007d-command-line-option_002c-CRIS-675"></a><a name="index-_0040option_007b_002d_002dno_002dunderscore_007d-command-line-option_002c-CRIS-676"></a><a name="index-CRIS-_0040option_007b_002d_002dunderscore_007d-command-line-option-677"></a><a name="index-CRIS-_0040option_007b_002d_002dno_002dunderscore_007d-command-line-option-678"></a>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 <span class="samp">_</span> 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 <span class="option">--underscore</span> and
<span class="option">--no-underscore</span>. The default is <span class="option">--underscore</span>.
Since symbols in CRIS a.out objects are expected to have a
<span class="samp">_</span> prefix, specifying <span class="option">--no-underscore</span> 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="crisnous.html#crisnous">crisnous</a>). The <span class="option">--no-underscore</span>
option makes a <span class="samp">$</span> register prefix mandatory.
<p><a name="index-_0040option_007b_002d_002dpic_007d-command-line-option_002c-CRIS-679"></a><a name="index-CRIS-_0040option_007b_002d_002dpic_007d-command-line-option-680"></a><a name="index-Position_002dindependent-code_002c-CRIS-681"></a><a name="index-CRIS-position_002dindependent-code-682"></a>The option <span class="option">--pic</span> 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="crispic.html#crispic">crispic</a>). This will also
affect expansion of instructions. The expansion with
<span class="option">--pic</span> will use PC-relative rather than (slightly
faster) absolute addresses in those expansions.
<p><a name="index-_0040option_007b_002d_002dmarch_003d_0040var_007barchitecture_007d_007d-command-line-option_002c-CRIS-683"></a><a name="index-CRIS-_0040option_007b_002d_002dmarch_003d_0040var_007barchitecture_007d_007d-command-line-option-684"></a><a name="index-Architecture-variant-option_002c-CRIS-685"></a><a name="index-CRIS-architecture-variant-option-686"></a>The option <span class="option">--march=</span><var>architecture</var>
<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:
<dl>
<dt><code>v0_v10</code><dd>All instructions and register names for any architecture variant
in the set v0<small class="dots">...</small>v10 are recognized. This is the
default if the target is configured as cris-*.
<br><dt><code>v10</code><dd>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-*.
<br><dt><code>v32</code><dd>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
<span class="option">--no-mul-bug-abort</span>. (A subsequent
<span class="option">--mul-bug-abort</span> will turn it back on.)
<br><dt><code>common_v10_v32</code><dd>Only instructions with register names and addressing modes with
opcodes common to the v10 and v32 are recognized.
</dl>
<p><a name="index-_0040option_007b_002dN_007d-command-line-option_002c-CRIS-687"></a><a name="index-CRIS-_0040option_007b_002dN_007d-command-line-option-688"></a>When <span class="option">-N</span> 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-_0040option_007b_002d_002dno_002dmul_002dbug_002dabort_007d-command-line-option_002c-CRIS-689"></a><a name="index-_0040option_007b_002d_002dmul_002dbug_002dabort_007d-command-line-option_002c-CRIS-690"></a><a name="index-CRIS-_0040option_007b_002d_002dno_002dmul_002dbug_002dabort_007d-command-line-option-691"></a><a name="index-CRIS-_0040option_007b_002d_002dmul_002dbug_002dabort_007d-command-line-option-692"></a>
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
<span class="option">--mul-bug-abort</span> 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
<span class="option">--mul-bug-abort</span> command line option turns off the
checking.
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