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<p class="MsoNormal"><o:p> </o:p></p>
<p class="MsoNormal">I would like to add a target-dependent attribute to the LLVM IR, and the guidance in
<a href="http://llvm.org/docs/HowToUseAttributes.html">http://llvm.org/docs/HowToUseAttributes.html</a> says that target-dependent attributes should not occupy a slot in the Attribute::AttrKind enum, but I have yet to find an attribute that is represented in
the IR that does not also have a slot in the AttrKind enum.<o:p></o:p></p>
<p class="MsoNormal"><o:p> </o:p></p>
<p class="MsoNormal">We are limited to 63 slots in the AttrKind enum because it is represented in the bitcode with a 64-bit bitmask. There is only one free slot left and I don’t want to use it for a target-dependent attribute. I had anticipated that only target-independent
attributes would have analogous ATTR_KIND identifiers in the AtttrKind enum, yet the ARM-specific CMSE_NS_CALL and CMSE_NS_ENTRY occupy slots in the AttrKind enum.<o:p></o:p></p>
<p class="MsoNormal"><o:p> </o:p></p>
<p class="MsoNormal">Can someone point me to an example of a target-dependent attribute represented in the LLVM IR that does not occupy a slot in the AttrKind enum?<o:p></o:p></p>
<p class="MsoNormal"><o:p> </o:p></p>
<p class="MsoNormal">Thanks,<o:p></o:p></p>
<p class="MsoNormal"><o:p> </o:p></p>
<p class="MsoNormal">Todd Snider<o:p></o:p></p>
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