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<th>Bug ID</th>
<td><a class="bz_bug_link
bz_status_NEW "
title="NEW - inaccessiblememonly and inaccessiblemem_or_argmemonly overwrite does not work on call with operand bundle"
href="https://bugs.llvm.org/show_bug.cgi?id=35128">35128</a>
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<th>Summary</th>
<td>inaccessiblememonly and inaccessiblemem_or_argmemonly overwrite does not work on call with operand bundle
</td>
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<th>Product</th>
<td>libraries
</td>
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<th>Version</th>
<td>5.0
</td>
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<th>Hardware</th>
<td>PC
</td>
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<th>OS</th>
<td>Linux
</td>
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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>yyc1992@gmail.com
</td>
</tr>
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<th>CC</th>
<td>llvm-bugs@lists.llvm.org
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<p>
<div>
<pre>According to LangRef,
<span class="quote">> Calls and invokes with operand bundles have unknown read / write effect on the heap on entry and exit (even if the call target is readnone or readonly), unless they’re overridden with callsite specific attributes.</span >
However, the callsite specific override seems to only work for `readonly`,
`readnone`, `argmemonly` but not for `inaccessiblememonly` and
`inaccessiblemem_or_argmemonly` as shown by the test case below,
```
target datalayout = "e-m:e-i64:64-f80:128-n8:16:32:64-S128"
target triple = "x86_64-unknown-linux-gnu"
%jl_value_t = type opaque
define i64 @f(i64* %p, i64 %v) {
store i64 %v, i64* %p
call void @g() #0 [ "unknown"(i64* %p) ]
%v2 = load i64, i64* %p
ret i64 %v2
}
declare void @g() #0
; attributes #0 = { inaccessiblememonly }
attributes #0 = { inaccessiblemem_or_argmemonly }
```
`opt -O3` does not remove the load instruction with either attributes but any
of the following does,
* Change the attribute to any one of `readonly`, `readnone`, `argmemonly`
* Remove the operand bundle.</pre>
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