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<th>Bug ID</th>
<td><a class="bz_bug_link
bz_status_NEW "
title="NEW - Fix aeabi_cfcmp.S and aeabi_cdcmp.S for Thumb2 MachO targets"
href="https://bugs.llvm.org/show_bug.cgi?id=34768">34768</a>
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<th>Summary</th>
<td>Fix aeabi_cfcmp.S and aeabi_cdcmp.S for Thumb2 MachO targets
</td>
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<th>Product</th>
<td>compiler-rt
</td>
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<th>Version</th>
<td>unspecified
</td>
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<th>Hardware</th>
<td>PC
</td>
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<th>OS</th>
<td>All
</td>
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<th>Status</th>
<td>NEW
</td>
</tr>
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<th>Severity</th>
<td>enhancement
</td>
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<th>Priority</th>
<td>P
</td>
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<th>Component</th>
<td>compiler-rt
</td>
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<th>Assignee</th>
<td>unassignedbugs@nondot.org
</td>
</tr>
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<th>Reporter</th>
<td>manojgupta@google.com
</td>
</tr>
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<th>CC</th>
<td>llvm-bugs@lists.llvm.org
</td>
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<th>Blocks</th>
<td>34715
</td>
</tr></table>
<p>
<div>
<pre>Peter Smith <<a href="mailto:Peter.Smith@arm.com">Peter.Smith@arm.com</a>> wrote:
To hazard a guess at what the problem is when compiling with Thumb2 using
--target=armv7k-watchos
The bne __aeabi_cdcmple is a Thumb2 conditional branch to a symbol defined in a
separate section (thanks to the subsections_via_symbols). In ELF there is a
relocation directive R_ARM_THM_JMP19 I think. Whereas I don't think that there
is one defined for Mach-O.
Personally if these symbols are in different sections it isn't ideal to use a
conditional branch in Thumb2 even when a relocation exists as the range is only
+- 1 MiB. I suggest when compiling in Thumb2 we separate the comparison and do
an unconditional branch.
This is blocking form landing fix for PR 34715.</pre>
</div>
</p>
<div id="referenced">
<hr style="border: 1px dashed #969696">
<b>Referenced Bugs:</b>
<ul>
<li>
[<a class="bz_bug_link
bz_status_NEW "
title="NEW - compiler-rt builtins are broken for thumb"
href="https://bugs.llvm.org/show_bug.cgi?id=34715">Bug 34715</a>] compiler-rt builtins are broken for thumb
</li>
</ul>
</div>
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