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| Previous: <a rel="previous" accesskey="p" href="AArch64_002dRegs.html#AArch64_002dRegs">AArch64-Regs</a>, |
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| <h5 class="subsubsection">9.1.3.3 Relocations</h5> |
| |
| <p><a name="index-relocations_002c-AArch64-557"></a><a name="index-AArch64-relocations-558"></a><a name="index-MOVN_002c-MOVZ-and-MOVK-group-relocations_002c-AArch64-559"></a>Relocations for ‘<samp><span class="samp">MOVZ</span></samp>’ and ‘<samp><span class="samp">MOVK</span></samp>’ instructions can be generated |
| by prefixing the label with ‘<samp><span class="samp">#:abs_g2:</span></samp>’ etc. |
| For example to load the 48-bit absolute address of <var>foo</var> into x0: |
| |
| <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> |
| <p><a name="index-ADRP_002c-ADD_002c-LDR_002fSTR-group-relocations_002c-AArch64-560"></a>Relocations for ‘<samp><span class="samp">ADRP</span></samp>’, and ‘<samp><span class="samp">ADD</span></samp>’, ‘<samp><span class="samp">LDR</span></samp>’ or ‘<samp><span class="samp">STR</span></samp>’ |
| instructions can be generated by prefixing the label with |
| ‘<samp><span class="samp">:pg_hi21:</span></samp>’ and ‘<samp><span class="samp">#:lo12:</span></samp>’ respectively. |
| |
| <p>For example to use 33-bit (+/-4GB) pc-relative addressing to |
| load the address of <var>foo</var> into x0: |
| |
| <pre class="smallexample"> adrp x0, :pg_hi21:foo |
| add x0, x0, #:lo12:foo |
| </pre> |
| <p>Or to load the value of <var>foo</var> into x0: |
| |
| <pre class="smallexample"> adrp x0, :pg_hi21:foo |
| ldr x0, [x0, #:lo12:foo] |
| </pre> |
| <p>Note that ‘<samp><span class="samp">:pg_hi21:</span></samp>’ is optional. |
| |
| <pre class="smallexample"> adrp x0, foo |
| </pre> |
| <p>is equivalent to |
| |
| <pre class="smallexample"> adrp x0, :pg_hi21:foo |
| </pre> |
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