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<th>Bug ID</th>
<td><a class="bz_bug_link
bz_status_NEW "
title="NEW - __divdf3 returns zero with some extreme values"
href="https://bugs.llvm.org/show_bug.cgi?id=51396">51396</a>
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<th>Summary</th>
<td>__divdf3 returns zero with some extreme values
</td>
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<th>Product</th>
<td>compiler-rt
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<th>Version</th>
<td>11.0
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<th>Hardware</th>
<td>Other
</td>
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<th>OS</th>
<td>other
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<th>Status</th>
<td>NEW
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<th>Severity</th>
<td>normal
</td>
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<th>Priority</th>
<td>P
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<th>Component</th>
<td>compiler-rt
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<th>Assignee</th>
<td>unassignedbugs@nondot.org
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<th>Reporter</th>
<td>aykevanlaethem@gmail.com
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<th>CC</th>
<td>llvm-bugs@lists.llvm.org
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<p>
<div>
<pre>I've found that __divdf3 returns an incorrect result for a specific input.
Specifically:
a = 1.7112092293746032e-193 (raw bits: 0x17E8FBBB7CBDC600)
b = 8.858903059828881e+116 (raw bits: 0x58367bbed68d8223)
result = __divdf3(a, b)
I've found that the output is 0, while all hardware implementations I've tested
this code with return a non-zero value: 1.9316265431712e-310 (raw bits:
0x0000238ee05c879e). Therefore, I think this is a bug in __divdf3.
In practice, this issue causes the math package in Go to fail the tests when
compiled with TinyGo and when using the compiler-rt library on a baremetal
system.</pre>
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