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<a name="Directives-i960"></a>
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<a name="Directives_002di960"></a>
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<p>
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Next: <a rel="next" accesskey="n" href="Opcodes-for-i960.html#Opcodes-for-i960">Opcodes for i960</a>,
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Previous: <a rel="previous" accesskey="p" href="Floating-Point_002di960.html#Floating-Point_002di960">Floating Point-i960</a>,
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Up: <a rel="up" accesskey="u" href="i960_002dDependent.html#i960_002dDependent">i960-Dependent</a>
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<h4 class="subsection">9.17.3 i960 Machine Directives</h4>
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<p><a name="index-machine-directives_002c-i960-1191"></a><a name="index-i960-machine-directives-1192"></a>
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<a name="index-g_t_0040code_007bbss_007d-directive_002c-i960-1193"></a>
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<dl><dt><code>.bss </code><var>symbol</var><code>, </code><var>length</var><code>, </code><var>align</var><dd>Reserve <var>length</var> bytes in the bss section for a local <var>symbol</var>,
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aligned to the power of two specified by <var>align</var>. <var>length</var> and
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<var>align</var> must be positive absolute expressions. This directive
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differs from ‘<samp><span class="samp">.lcomm</span></samp>’ only in that it permits you to specify
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an alignment. See <a href="Lcomm.html#Lcomm"><code>.lcomm</code></a>.
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</dl>
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<a name="index-g_t_0040code_007bextended_007d-directive_002c-i960-1194"></a>
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<dl><dt><code>.extended </code><var>flonums</var><dd><code>.extended</code> expects zero or more flonums, separated by commas; for
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each flonum, ‘<samp><span class="samp">.extended</span></samp>’ emits an <span class="sc">ieee</span> extended-format (80-bit)
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floating-point number.
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<p><a name="index-g_t_0040code_007bleafproc_007d-directive_002c-i960-1195"></a><br><dt><code>.leafproc </code><var>call-lab</var><code>, </code><var>bal-lab</var><dd>You can use the ‘<samp><span class="samp">.leafproc</span></samp>’ directive in conjunction with the
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optimized <code>callj</code> instruction to enable faster calls of leaf
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procedures. If a procedure is known to call no other procedures, you
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may define an entry point that skips procedure prolog code (and that does
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not depend on system-supplied saved context), and declare it as the
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<var>bal-lab</var> using ‘<samp><span class="samp">.leafproc</span></samp>’. If the procedure also has an
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entry point that goes through the normal prolog, you can specify that
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entry point as <var>call-lab</var>.
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<p>A ‘<samp><span class="samp">.leafproc</span></samp>’ declaration is meant for use in conjunction with the
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optimized call instruction ‘<samp><span class="samp">callj</span></samp>’; the directive records the data
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needed later to choose between converting the ‘<samp><span class="samp">callj</span></samp>’ into a
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<code>bal</code> or a <code>call</code>.
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<p><var>call-lab</var> is optional; if only one argument is present, or if the
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two arguments are identical, the single argument is assumed to be the
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<code>bal</code> entry point.
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<p><a name="index-g_t_0040code_007bsysproc_007d-directive_002c-i960-1196"></a><br><dt><code>.sysproc </code><var>name</var><code>, </code><var>index</var><dd>The ‘<samp><span class="samp">.sysproc</span></samp>’ directive defines a name for a system procedure.
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After you define it using ‘<samp><span class="samp">.sysproc</span></samp>’, you can use <var>name</var> to
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refer to the system procedure identified by <var>index</var> when calling
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procedures with the optimized call instruction ‘<samp><span class="samp">callj</span></samp>’.
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<p>Both arguments are required; <var>index</var> must be between 0 and 31
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(inclusive).
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</dl>
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