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<p class="MsoNormal"><span style="font-size:11.0pt;font-family:"Calibri","sans-serif";color:#1F497D">Would you mind terribly waiting a week, until after 3.6 is forked?<o:p></o:p></span></p>
<p class="MsoNormal"><span style="font-size:11.0pt;font-family:"Calibri","sans-serif";color:#1F497D">We're barely caught up with the last big metadata syntax change.<o:p></o:p></span></p>
<p class="MsoNormal"><span style="font-size:11.0pt;font-family:"Calibri","sans-serif";color:#1F497D">Thanks,<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"><a name="_MailEndCompose"><span style="font-size:11.0pt;font-family:"Calibri","sans-serif";color:#1F497D"><o:p> </o:p></span></a></p>
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<p class="MsoNormal"><b><span style="font-size:10.0pt;font-family:"Tahoma","sans-serif"">From:</span></b><span style="font-size:10.0pt;font-family:"Tahoma","sans-serif""> llvmdev-bounces@cs.uiuc.edu [mailto:llvmdev-bounces@cs.uiuc.edu]
<b>On Behalf Of </b>Duncan P. N. Exon Smith<br>
<b>Sent:</b> Monday, January 12, 2015 8:30 PM<br>
<b>To:</b> LLVM Developers Mailing List<br>
<b>Subject:</b> [LLVMdev] [RFC] First-class debug info IR: MDLocation (redux)<o:p></o:p></span></p>
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<p class="MsoNormal"><o:p> </o:p></p>
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<p class="MsoNormal" style="margin-bottom:12.0pt"><span style="font-size:10.0pt">After splitting `Metadata` apart from `Value`, I'm finally back to the<br>
first step [1] of representing debug info more directly in IR [2]:<br>
`MDLocation`.<br>
<br>
[1]: <a href="http://lists.cs.uiuc.edu/pipermail/llvmdev/2014-October/078173.html">
http://lists.cs.uiuc.edu/pipermail/llvmdev/2014-October/078173.html</a><br>
"First-class debug info IR: MDLocation"<br>
[2]: <a href="http://lists.cs.uiuc.edu/pipermail/llvmdev/2014-October/077715.html">
http://lists.cs.uiuc.edu/pipermail/llvmdev/2014-October/077715.html</a><br>
"Less memory and greater maintainability for debug info IR"<br>
<br>
I've attached two patches which are both essentially commit-ready (just<br>
missing LangRef update, AFAIK), although they just add the class and<br>
assembly/bitcode support. Once it's in tree, I'll move it into place<br>
underneath `DebugLoc` and `DILocation` and update the world of<br>
testcases, publish a script, and so forth.<br>
<br>
Assembly syntax<br>
===============<br>
<br>
I've changed the assembly syntax a little since my previous proposal<br>
[1], but I kept the fundamentals the same:<br>
<br>
- Fields use key/value pairs and can be specified in any order.<br>
- No types (unless you're referencing a `Value`).<br>
- Some fields are required (in this case, 'scope:').<br>
- Unspecified fields get sane default values.<br>
<br>
Old syntax:<br>
<br>
!6 = metadata MDLocation(line: 43, column: 7, scope: !4)<br>
<br>
Now it's:<br>
<br>
!6 = !MDLocation(line: 43, column: 7, scope: !4)<br>
<br>
Here's why:<br>
<br>
- Dropped 'metadata' since `Metadata` is now typeless \O/.<br>
<br>
- Added a '!' since it makes the parser simpler (no changes to the<br>
lexer, since we can unambiguously reuse the `MetadataVar` token),<br>
and follows the rule that "All metadata are identified in syntax by<br>
a[n] exclamation point" [3]. (If people are opposed to the extra<br>
'!' I can update this sentence instead, but it seems like a handy<br>
mnemonic to maintain.)<br>
<br>
[3]: <a href="http://llvm.org/docs/LangRef.html#metadata">http://llvm.org/docs/LangRef.html#metadata</a><br>
<br>
Where this is heading<br>
=====================<br>
<br>
See my previous post [1] ;).<o:p></o:p></span></p>
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<p class="MsoNormal"><span style="font-size:10.0pt">_______________________________________________<br>
LLVM Developers mailing list<br>
<a href="mailto:LLVMdev@cs.uiuc.edu">LLVMdev@cs.uiuc.edu</a> <a href="http://llvm.cs.uiuc.edu">
http://llvm.cs.uiuc.edu</a><br>
<a href="http://lists.cs.uiuc.edu/mailman/listinfo/llvmdev">http://lists.cs.uiuc.edu/mailman/listinfo/llvmdev</a><o:p></o:p></span></p>
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