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- <a name="AArch64_002dRelocations"></a>
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- <p>
- Previous: <a href="AArch64_002dRegs.html#AArch64_002dRegs" accesskey="p" rel="prev">AArch64-Regs</a>, Up: <a href="AArch64-Syntax.html#AArch64-Syntax" accesskey="u" rel="up">AArch64 Syntax</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="Relocations"></a>
- <h4 class="subsubsection">9.1.3.3 Relocations</h4>
-
- <a name="index-relocations_002c-AArch64"></a>
- <a name="index-AArch64-relocations"></a>
- <a name="index-MOVN_002c-MOVZ-and-MOVK-group-relocations_002c-AArch64"></a>
- <p>Relocations for ‘<samp>MOVZ</samp>’ and ‘<samp>MOVK</samp>’ instructions can be generated
- by prefixing the label with ‘<samp>#:abs_g2:</samp>’ etc.
- For example to load the 48-bit absolute address of <var>foo</var> into x0:
- </p>
- <div class="smallexample">
- <pre class="smallexample"> movz x0, #:abs_g2:foo // bits 32-47, overflow check
- movk x0, #:abs_g1_nc:foo // bits 16-31, no overflow check
- movk x0, #:abs_g0_nc:foo // bits 0-15, no overflow check
- </pre></div>
-
- <a name="index-ADRP_002c-ADD_002c-LDR_002fSTR-group-relocations_002c-AArch64"></a>
- <p>Relocations for ‘<samp>ADRP</samp>’, and ‘<samp>ADD</samp>’, ‘<samp>LDR</samp>’ or ‘<samp>STR</samp>’
- instructions can be generated by prefixing the label with
- ‘<samp>:pg_hi21:</samp>’ and ‘<samp>#:lo12:</samp>’ respectively.
- </p>
- <p>For example to use 33-bit (+/-4GB) pc-relative addressing to
- load the address of <var>foo</var> into x0:
- </p>
- <div class="smallexample">
- <pre class="smallexample"> adrp x0, :pg_hi21:foo
- add x0, x0, #:lo12:foo
- </pre></div>
-
- <p>Or to load the value of <var>foo</var> into x0:
- </p>
- <div class="smallexample">
- <pre class="smallexample"> adrp x0, :pg_hi21:foo
- ldr x0, [x0, #:lo12:foo]
- </pre></div>
-
- <p>Note that ‘<samp>:pg_hi21:</samp>’ is optional.
- </p>
- <div class="smallexample">
- <pre class="smallexample"> adrp x0, foo
- </pre></div>
-
- <p>is equivalent to
- </p>
- <div class="smallexample">
- <pre class="smallexample"> adrp x0, :pg_hi21:foo
- </pre></div>
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