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| <a name="AArch64-Directives"></a> |
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| Next: <a href="AArch64-Opcodes.html#AArch64-Opcodes" accesskey="n" rel="next">AArch64 Opcodes</a>, Previous: <a href="AArch64-Floating-Point.html#AArch64-Floating-Point" accesskey="p" rel="prev">AArch64 Floating Point</a>, Up: <a href="AArch64_002dDependent.html#AArch64_002dDependent" accesskey="u" rel="up">AArch64-Dependent</a> [<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="AArch64-Machine-Directives"></a> |
| <h4 class="subsection">9.1.5 AArch64 Machine Directives</h4> |
| |
| <a name="index-machine-directives_002c-AArch64"></a> |
| <a name="index-AArch64-machine-directives"></a> |
| <dl compact="compact"> |
| <dd> |
| |
| <a name="index-_002ebss-directive_002c-AArch64"></a> |
| </dd> |
| <dt><code>.bss</code></dt> |
| <dd><p>This directive switches to the <code>.bss</code> section. |
| </p> |
| |
| <a name="index-_002eltorg-directive_002c-AArch64"></a> |
| </dd> |
| <dt><code>.ltorg</code></dt> |
| <dd><p>This directive causes the current contents of the literal pool to be |
| dumped into the current section (which is assumed to be the .text |
| section) at the current location (aligned to a word boundary). |
| GAS maintains a separate literal pool for each section and each |
| sub-section. The <code>.ltorg</code> directive will only affect the literal |
| pool of the current section and sub-section. At the end of assembly |
| all remaining, un-empty literal pools will automatically be dumped. |
| </p> |
| <p>Note - older versions of GAS would dump the current literal |
| pool any time a section change occurred. This is no longer done, since |
| it prevents accurate control of the placement of literal pools. |
| </p> |
| |
| |
| |
| <a name="index-_002epool-directive_002c-AArch64"></a> |
| </dd> |
| <dt><code>.pool</code></dt> |
| <dd><p>This is a synonym for .ltorg. |
| </p> |
| |
| <a name="index-_002ereq-directive_002c-AArch64"></a> |
| </dd> |
| <dt><code><var>name</var> .req <var>register name</var></code></dt> |
| <dd><p>This creates an alias for <var>register name</var> called <var>name</var>. For |
| example: |
| </p> |
| <div class="smallexample"> |
| <pre class="smallexample"> foo .req w0 |
| </pre></div> |
| |
| |
| |
| |
| <a name="index-_002eunreq-directive_002c-AArch64"></a> |
| </dd> |
| <dt><code>.unreq <var>alias-name</var></code></dt> |
| <dd><p>This undefines a register alias which was previously defined using the |
| <code>req</code> directive. For example: |
| </p> |
| <div class="smallexample"> |
| <pre class="smallexample"> foo .req w0 |
| .unreq foo |
| </pre></div> |
| |
| <p>An error occurs if the name is undefined. Note - this pseudo op can |
| be used to delete builtin in register name aliases (eg ’w0’). This |
| should only be done if it is really necessary. |
| </p> |
| |
| |
| </dd> |
| </dl> |
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