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- Next: <a href="ARM-Unwinding-Tutorial.html#ARM-Unwinding-Tutorial" accesskey="n" rel="next">ARM Unwinding Tutorial</a>, Previous: <a href="ARM-Opcodes.html#ARM-Opcodes" accesskey="p" rel="prev">ARM Opcodes</a>, Up: <a href="ARM_002dDependent.html#ARM_002dDependent" accesskey="u" rel="up">ARM-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="Mapping-Symbols-1"></a>
- <h4 class="subsection">9.4.6 Mapping Symbols</h4>
-
- <p>The ARM ELF specification requires that special symbols be inserted
- into object files to mark certain features:
- </p>
- <dl compact="compact">
- <dd>
- <a name="index-_0024a"></a>
- </dd>
- <dt><code>$a</code></dt>
- <dd><p>At the start of a region of code containing ARM instructions.
- </p>
- <a name="index-_0024t"></a>
- </dd>
- <dt><code>$t</code></dt>
- <dd><p>At the start of a region of code containing THUMB instructions.
- </p>
- <a name="index-_0024d-1"></a>
- </dd>
- <dt><code>$d</code></dt>
- <dd><p>At the start of a region of data.
- </p>
- </dd>
- </dl>
-
- <p>The assembler will automatically insert these symbols for you - there
- is no need to code them yourself. Support for tagging symbols ($b,
- $f, $p and $m) which is also mentioned in the current ARM ELF
- specification is not implemented. This is because they have been
- dropped from the new EABI and so tools cannot rely upon their
- presence.
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