<div dir="ltr"><div class="gmail_extra"><br><div class="gmail_quote">On Wed, May 7, 2014 at 11:38 AM, Keno Fischer <span dir="ltr"><<a href="mailto:kfischer@college.harvard.edu" target="_blank">kfischer@college.harvard.edu</a>></span> wrote:<br>
<blockquote class="gmail_quote" style="margin:0 0 0 .8ex;border-left:1px #ccc solid;padding-left:1ex"><div dir="ltr">The use case for this is in Julia backtraces. We don't have a consistent way to mangle the function names for linkage (we might at some point in the future, but this is out of scope for now). Instead, we save whatever we want displayed in AT_name, but there's no way to access that with the public API (it works nicely in gdb/lldb though). </div>
</blockquote><div><br></div><div>Alright, I see why it makes sense. We can pass this information through DILineInfoSpecifier. In fact, probably it makes sense to change the layout of this structure:</div><div>there would be 3 types of file/line info (None, Regular, AbsoluteFilePath). (though, probably we may make latter the default) and 3 types of function name info (None, Name, LinkageName).</div>
<div> </div><blockquote class="gmail_quote" style="margin:0 0 0 .8ex;border-left:1px #ccc solid;padding-left:1ex"><div class="HOEnZb"><div class="h5">
<div class="gmail_extra"><br><br><div class="gmail_quote">On Wed, May 7, 2014 at 2:36 PM, Alexey Samsonov <span dir="ltr"><<a href="mailto:samsonov@google.com" target="_blank">samsonov@google.com</a>></span> wrote:<br>
<blockquote class="gmail_quote" style="margin:0 0 0 .8ex;border-left:1px #ccc solid;padding-left:1ex"><div dir="ltr"><div class="gmail_extra"><br><div class="gmail_quote"><div>On Wed, May 7, 2014 at 11:33 AM, Eric Christopher <span dir="ltr"><<a href="mailto:echristo@gmail.com" target="_blank">echristo@gmail.com</a>></span> wrote:<br>
<blockquote class="gmail_quote" style="margin:0 0 0 .8ex;border-left:1px #ccc solid;padding-left:1ex">Have you checked out llvm-symbolize? It's what the asan folk<br>
(including Alexey) have created for backtrace symbolication.<br></blockquote><div><br></div></div><div>Yeah, we potentially can add some kind of option: "llvm-symbolizer -print-short-function-names", I don't yet see why this would be valuable.</div>
<div>What's wrong with printing full function names?</div><div><div><div> </div><blockquote class="gmail_quote" style="margin:0 0 0 .8ex;border-left:1px #ccc solid;padding-left:1ex">
<span><font color="#888888"><br>
-eric<br>
</font></span><div><div><br>
On Wed, May 7, 2014 at 11:28 AM, Isaiah Norton <<a href="mailto:isaiah.norton@gmail.com" target="_blank">isaiah.norton@gmail.com</a>> wrote:<br>
> The use case is getting the short name for backtraces. There are other<br>
> options, but I figured it was worth a shot trying to access from the DWARF<br>
> structure because what we need is already stored there anyway.<br>
><br>
> Thanks,<br>
> Isaiah<br>
><br>
><br>
> On Wed, May 7, 2014 at 12:24 PM, Alexey Samsonov <<a href="mailto:samsonov@google.com" target="_blank">samsonov@google.com</a>><br>
> wrote:<br>
>><br>
>> Yeah, public API of DebugInfo library is quite minimalistic. But I agree<br>
>> with Eric - what is the use case for getting unmangled name from DIE?<br>
>><br>
>><br>
>> On Tue, May 6, 2014 at 11:21 PM, Keno Fischer<br>
>> <<a href="mailto:kfischer@college.harvard.edu" target="_blank">kfischer@college.harvard.edu</a>> wrote:<br>
>>><br>
>>> That doesn't seem possible with the public API or am I mistaking?<br>
>>><br>
>>><br>
>>> On Wed, May 7, 2014 at 12:13 AM, Eric Christopher <<a href="mailto:echristo@gmail.com" target="_blank">echristo@gmail.com</a>><br>
>>> wrote:<br>
>>>><br>
>>>> On Tue, May 6, 2014 at 8:09 PM, Isaiah Norton <<a href="mailto:isaiah.norton@gmail.com" target="_blank">isaiah.norton@gmail.com</a>><br>
>>>> wrote:<br>
>>>> > Hi,<br>
>>>> ><br>
>>>> > I am looking for a way to get unmangled subprogram names from a<br>
>>>> > DWARFContext. The name I want is available in the attribute<br>
>>>> > `DW_AT_name`<br>
>>>> > [1], but as far as I can tell this is only returned as a fallback in<br>
>>>> > `DWARFDebugInfoEntryMinimal::getSubroutineName` when the linkage name<br>
>>>> > is not<br>
>>>> > available [2].<br>
>>>> ><br>
>>>> > If this is not currently possible, is there any interest in adding<br>
>>>> > such<br>
>>>> > access to the public DebugInfo API? Perhaps with an additional<br>
>>>> > "UnmangledName" option in `DILineInfoSpecifier`.<br>
>>>> ><br>
>>>> > Thanks,<br>
>>>> > Isaiah<br>
>>>> ><br>
>>>> > [1]: for example:<br>
>>>> ><br>
>>>> > 0x0001bb00: DW_TAG_subprogram [2]<br>
>>>> > DW_AT_MIPS_linkage_name [DW_FORM_strp] (<br>
>>>> > .debug_str[0x00007934] = "julia_vcat4473")<br>
>>>> > DW_AT_name [DW_FORM_strp] (<br>
>>>> > .debug_str[0x00000913] =<br>
>>>> > "vcat")<br>
>>>> ><br>
>>>> ><br>
>>>> > [2]<br>
>>>> ><br>
>>>> > <a href="https://github.com/llvm-mirror/llvm/blob/master/lib/DebugInfo/DWARFDebugInfoEntry.cpp#L279-L286" target="_blank">https://github.com/llvm-mirror/llvm/blob/master/lib/DebugInfo/DWARFDebugInfoEntry.cpp#L279-L286</a><br>
>>>> ><br>
>>>> ><br>
>>>><br>
>>>> If you just want the DW_AT_name you should be able to iterate over the<br>
>>>> DIEs and pull out the DW_AT_name attribute from all of the subprogram<br>
>>>> DIEs. Is there some other use that you're looking for? I'm not quite<br>
>>>> sure what you're trying to accomplish.<br>
>>>><br>
>>>> -eric<br>
>>>> _______________________________________________<br>
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>>>> <a href="http://lists.cs.uiuc.edu/mailman/listinfo/llvmdev" target="_blank">http://lists.cs.uiuc.edu/mailman/listinfo/llvmdev</a><br>
>>><br>
>>><br>
>>><br>
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>>> <a href="http://lists.cs.uiuc.edu/mailman/listinfo/llvmdev" target="_blank">http://lists.cs.uiuc.edu/mailman/listinfo/llvmdev</a><br>
>>><br>
>><br>
>><br>
>><br>
>> --<br>
>> Alexey Samsonov, Mountain View, CA<br>
>><br>
>> _______________________________________________<br>
>> LLVM Developers mailing list<br>
>> <a href="mailto:LLVMdev@cs.uiuc.edu" target="_blank">LLVMdev@cs.uiuc.edu</a> <a href="http://llvm.cs.uiuc.edu" target="_blank">http://llvm.cs.uiuc.edu</a><br>
>> <a href="http://lists.cs.uiuc.edu/mailman/listinfo/llvmdev" target="_blank">http://lists.cs.uiuc.edu/mailman/listinfo/llvmdev</a><br>
>><br>
><br>
><br>
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><br>
</div></div></blockquote></div></div></div><div><div><br><br clear="all"><div><br></div>-- <br><div dir="ltr"><div>Alexey Samsonov, Mountain View, CA</div></div>
</div></div></div></div>
</blockquote></div><br></div>
</div></div></blockquote></div><br><br clear="all"><div><br></div>-- <br><div dir="ltr"><div>Alexey Samsonov, Mountain View, CA</div></div>
</div></div>