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<a name="Other-poly_005fint-arithmetic"></a>
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<p>
Previous: <a href="Division-of-poly_005fints.html#Division-of-poly_005fints" accesskey="p" rel="prev">Division of <code>poly_int</code>s</a>, Up: <a href="Arithmetic-on-poly_005fints.html#Arithmetic-on-poly_005fints" accesskey="u" rel="up">Arithmetic on <code>poly_int</code>s</a> &nbsp; [<a href="index.html#SEC_Contents" title="Table of contents" rel="contents">Contents</a>][<a href="Option-Index.html#Option-Index" title="Index" rel="index">Index</a>]</p>
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<a name="Other-poly_005fint-arithmetic-1"></a>
<h4 class="subsection">10.4.4 Other <code>poly_int</code> arithmetic</h4>

<p>There are tentative routines for other operations besides division:
</p>
<dl compact="compact">
<dt>&lsquo;<samp>can_ior_p (<var>a</var>, <var>b</var>, &amp;<var>result</var>)</samp>&rsquo;</dt>
<dd><p>Return true if we can calculate &lsquo;<samp><var>a</var> | <var>b</var></samp>&rsquo; at compile time,
storing the result in <var>result</var> if so.
</p></dd>
</dl>

<p>Also, ANDs with a value &lsquo;<samp>(1 &lt;&lt; <var>y</var>) - 1</samp>&rsquo; or its inverse can be
treated as alignment operations.  See <a href="Alignment-of-poly_005fints.html#Alignment-of-poly_005fints">Alignment of <code>poly_int</code>s</a>.
</p>
<p>In addition, the following miscellaneous routines are available:
</p>
<dl compact="compact">
<dt>&lsquo;<samp>coeff_gcd (<var>a</var>)</samp>&rsquo;</dt>
<dd><p>Return the greatest common divisor of all nonzero coefficients in
<var>a</var>, or zero if <var>a</var> is known to be zero.
</p>
</dd>
<dt>&lsquo;<samp>common_multiple (<var>a</var>, <var>b</var>)</samp>&rsquo;</dt>
<dd><p>Return a value that is a multiple of both <var>a</var> and <var>b</var>, where
one value is a <code>poly_int</code> and the other is a scalar.  The result
will be the least common multiple for some indeterminate values but
not necessarily for all.
</p>
</dd>
<dt>&lsquo;<samp>force_common_multiple (<var>a</var>, <var>b</var>)</samp>&rsquo;</dt>
<dd><p>Return a value that is a multiple of both <code>poly_int</code> <var>a</var> and
<code>poly_int</code> <var>b</var>, asserting that such a value exists.  The
result will be the least common multiple for some indeterminate values
but not necessarily for all.
</p>
<p>When using this routine, please add a comment explaining why the
assertion is known to hold.
</p></dd>
</dl>

<p>Please add any other operations that you find to be useful.
</p>


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