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<p class="MsoNormal">================<br>
Comment at: llvm/lib/DebugInfo/DWARF/DWARFFormValue.cpp:64<br>
+DWARFFormValue::getFixedByteSize(dwarf::Form Form,<br>
+ const DWARFFormParams *Params) {<br>
switch (Form) {<br>
----------------<br>
dblaikie wrote:<br>
> Should this be optional? The only place that doesn't pass it looks to be DWARFAbbreviationDeclaration::extract - is that usage correct? Does the abbrev table implicit_const not support the extra features? Should there be some error path/check for any forms
that would require the params?<br>
There is a use-case for scanning the abbreviations table to determine which ones are fixed-size in all cases. And the abbreviations table can be shared by units/line-tables with different formats/versions. This was an important point for @clayborg and LLDB,
I think.<br>
So yes, I think it should remain optional. We can change our minds later if I'm wrong.<o:p></o:p></p>
<p class="MsoNormal"><o:p> </o:p></p>
<p class="MsoNormal">Still might be worth moving the optionality to that one use case & adding some comments about why it's probably valid there so it doesn't get accidentally propagated to other users.<o:p></o:p></p>
<p class="MsoNormal"> <o:p></o:p></p>
<p class="MsoNormal"><span style="font-size:11.0pt;font-family:"Calibri","sans-serif";color:#1F497D">So we would have something like:<o:p></o:p></span></p>
<p class="MsoNormal"><span style="font-size:11.0pt;font-family:"Calibri","sans-serif";color:#1F497D"> Optional<uint8_t> getFixedByteSize(dwarf::Form Form, const DWARFFormParams &Params);<o:p></o:p></span></p>
<p class="MsoNormal"><span style="font-size:11.0pt;font-family:"Calibri","sans-serif";color:#1F497D"> Optional<uint8_t> getFixedByteSizeForAbbrev(dwarf::Form Form);<o:p></o:p></span></p>
<p class="MsoNormal"><span style="font-size:11.0pt;font-family:"Calibri","sans-serif";color:#1F497D">with commentary reinforcing the special case. I can do that.<o:p></o:p></span></p>
<p class="MsoNormal"><span style="font-size:11.0pt;font-family:"Calibri","sans-serif";color:#1F497D">--paulr<o:p></o:p></span></p>
<p class="MsoNormal"><span style="font-size:11.0pt;font-family:"Calibri","sans-serif";color:#1F497D"><o:p> </o:p></span></p>
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<p class="MsoNormal" style="margin-bottom:12.0pt"><a href="https://reviews.llvm.org/D34570" target="_blank">https://reviews.llvm.org/D34570</a><o:p></o:p></p>
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