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<th>Bug ID</th>
<td><a class="bz_bug_link
bz_status_NEW "
title="NEW - [AARCH64] vector zext hangs/crashes with NEON disabled"
href="https://bugs.llvm.org/show_bug.cgi?id=43719">43719</a>
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<th>Summary</th>
<td>[AARCH64] vector zext hangs/crashes with NEON disabled
</td>
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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>Other
</td>
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<th>OS</th>
<td>All
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<th>Status</th>
<td>NEW
</td>
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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>Backend: AArch64
</td>
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<th>Assignee</th>
<td>unassignedbugs@nondot.org
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<th>Reporter</th>
<td>husseydevin@gmail.com
</td>
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<th>CC</th>
<td>arnaud.degrandmaison@arm.com, llvm-bugs@lists.llvm.org, peter.smith@linaro.org, Ties.Stuij@arm.com
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<p>
<div>
<pre>define @zext_v2xi32(<2 x i32> %vec)
{
%extended = zext <2 x i32> %vec to <2 x i64>
ret <2 x i64> %extended
}
llc -march=aarch64 -mattr=-neon
I would expect something like this (if I am correct in that <2 x i32> is passed
as i32 *):
zext_v2xi32:
ldp w0, w1, [x0]
ret
But instead, I either get a segfault (on Termux's 8.0.1 build), or an infinite
loop (9.0.0 on archlinuxarm or trunk w/debug). With every other known
architecture, SIMD types still scalarize properly with SIMD disabled, given
that llvm intrinsics aren't used.
Enabling debug output in llc spams this:
Combining: t7: i64 = Constant<0>
Combining: t6: v2i64 = zero_extend t5
Creating new node: tNNNNN: v1i64 = extract_subvector t6, Constant:i64<0>
Creating new node: tNNNNN+1: v1i64 = extract_subvector t6, Constant:i64<1></pre>
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