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<th>Bug ID</th>
<td><a class="bz_bug_link
bz_status_NEW "
title="NEW - InstCombiner::PromoteCastOfAllocation performs irrelevant check of type alignment"
href="https://bugs.llvm.org/show_bug.cgi?id=32259">32259</a>
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<th>Summary</th>
<td>InstCombiner::PromoteCastOfAllocation performs irrelevant check of type alignment
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<th>Product</th>
<td>libraries
</td>
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<th>Version</th>
<td>trunk
</td>
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<th>Hardware</th>
<td>PC
</td>
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<th>OS</th>
<td>Linux
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<th>Status</th>
<td>NEW
</td>
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<th>Severity</th>
<td>enhancement
</td>
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<th>Priority</th>
<td>P
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<th>Component</th>
<td>Scalar Optimizations
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<th>Assignee</th>
<td>unassignedbugs@nondot.org
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<th>Reporter</th>
<td>richard-llvm@metafoo.co.uk
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<th>CC</th>
<td>llvm-bugs@lists.llvm.org
</td>
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<p>
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<pre>Instcombine fails to fold the bitcast into the alloca for 'n' in this case:
void f() { int n; char *volatile p = (char*)&n; }
... because it (incorrectly, as far as I can tell) thinks the ABI alignment of
the source and destination types is in some way relevant to the transformation.
Instead, it should ignore type alignment entirely and instead simply preserve
the alignment of the incoming alloca (setting it to the alignment of the
original type in the process, if it was previously omitted).</pre>
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