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<th>Bug ID</th>
<td><a class="bz_bug_link
bz_status_NEW "
title="NEW - [AMDGPU][MC] Default MIMG dmask is 0 which is illegal for GATHER/ATOMIC opcodes"
href="https://bugs.llvm.org/show_bug.cgi?id=39320">39320</a>
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<th>Summary</th>
<td>[AMDGPU][MC] Default MIMG dmask is 0 which is illegal for GATHER/ATOMIC opcodes
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<th>Product</th>
<td>libraries
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<th>Version</th>
<td>trunk
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<th>Hardware</th>
<td>PC
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<th>OS</th>
<td>All
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<th>Status</th>
<td>NEW
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<th>Severity</th>
<td>enhancement
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<th>Priority</th>
<td>P
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<th>Component</th>
<td>Backend: AMDGPU
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<th>Assignee</th>
<td>unassignedbugs@nondot.org
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<th>Reporter</th>
<td>dpreobrazhensky@luxoft.com
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<th>CC</th>
<td>llvm-bugs@lists.llvm.org
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<p>
<div>
<pre>In the current implementation, dmask is an optional modifier. When omitted,
dmask value defaults to zero.
However there are MIMG opcodes for which zero dmask is illegal:
- all GATHER opcodes
- all ATOMIC opcodes
This result in unclear behavior and error messages. For example, the code
image_gather4 v[0:3], v[0:1], s[0:7], s[0:3]
trigger the following error message:
invalid image_gather dmask: only one bit must be set
I believe that an optional modifier should always provide a legal value.
Unfortunately there is no dmask value that is legal for all opcodes.
Should we change dmask to be a mandatory modifier?
Any suggestions?</pre>
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