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<p class="MsoNormal" style="background:white"><span style="font-size:11.0pt;font-family:"Segoe UI","sans-serif";color:#1F497D">Hi Chandler,</span><span style="font-size:10.0pt;font-family:"Segoe UI","sans-serif";color:black"><o:p></o:p></span></p>
<p class="MsoNormal" style="background:white"><span style="font-size:11.0pt;font-family:"Segoe UI","sans-serif";color:#1F497D"> </span><span style="font-size:10.0pt;font-family:"Segoe UI","sans-serif";color:black"><o:p></o:p></span></p>
<p class="MsoNormal" style="background:white"><span style="font-size:11.0pt;font-family:"Segoe UI","sans-serif";color:#1F497D">I think I have shortened the metadata as much as I could. Out of 91 entries that I had in the original patch, I now have only 7.</span><span style="font-size:10.0pt;font-family:"Segoe UI","sans-serif";color:black"><o:p></o:p></span></p>
<p class="MsoNormal" style="background:white"><span style="font-size:11.0pt;font-family:"Segoe UI","sans-serif";color:#1F497D"> </span><span style="font-size:10.0pt;font-family:"Segoe UI","sans-serif";color:black"><o:p></o:p></span></p>
<p class="MsoNormal" style="background:white"><span style="font-size:11.0pt;font-family:"Segoe UI","sans-serif";color:#1F497D">!38 = metadata !{i32 786688, null, metadata !"var2", null, i32 20, null, i32 0, i32 0} ; [ DW_TAG_auto_variable ] [var2] [line 20]</span><span style="font-size:10.0pt;font-family:"Segoe UI","sans-serif";color:black"><o:p></o:p></span></p>
<p class="MsoNormal" style="background:white"><span style="font-size:11.0pt;font-family:"Segoe UI","sans-serif";color:#1F497D">!48 = metadata !{i32 2, metadata !"Dwarf Version", i32 4}</span><span style="font-size:10.0pt;font-family:"Segoe UI","sans-serif";color:black"><o:p></o:p></span></p>
<p class="MsoNormal" style="background:white"><span style="font-size:11.0pt;font-family:"Segoe UI","sans-serif";color:#1F497D">!49 = metadata !{i32 1, metadata !"Debug Info Version", i32 1}</span><span style="font-size:10.0pt;font-family:"Segoe UI","sans-serif";color:black"><o:p></o:p></span></p>
<p class="MsoNormal" style="background:white"><span style="font-size:11.0pt;font-family:"Segoe UI","sans-serif";color:#1F497D">!50 = metadata !{metadata !"clang version 3.5 (202418)"}</span><span style="font-size:10.0pt;font-family:"Segoe UI","sans-serif";color:black"><o:p></o:p></span></p>
<p class="MsoNormal" style="background:white"><span style="font-size:11.0pt;font-family:"Segoe UI","sans-serif";color:#1F497D">!60 = metadata !{i32 786689, null, metadata !"this", null, i32 16777216, null, i32 1088, null} ; [ DW_TAG_arg_variable ] [this] [line
0]</span><span style="font-size:10.0pt;font-family:"Segoe UI","sans-serif";color:black"><o:p></o:p></span></p>
<p class="MsoNormal" style="background:white"><span style="font-size:11.0pt;font-family:"Segoe UI","sans-serif";color:#1F497D">!62 = metadata !{i8* getelementptr inbounds ([1 x i8]* @.str, i64 0, i64 0)}</span><span style="font-size:10.0pt;font-family:"Segoe UI","sans-serif";color:black"><o:p></o:p></span></p>
<p class="MsoNormal" style="background:white"><span style="font-size:11.0pt;font-family:"Segoe UI","sans-serif";color:#1F497D">!63 = metadata !{i32 786689, null, metadata !"value", null, i32 33554439, null, i32 0, null} ; [ DW_TAG_arg_variable ] [value] [line
7]</span><span style="font-size:10.0pt;font-family:"Segoe UI","sans-serif";color:black"><o:p></o:p></span></p>
<p class="MsoNormal" style="background:white"><span style="font-size:11.0pt;font-family:"Segoe UI","sans-serif";color:#1F497D"> </span><span style="font-size:10.0pt;font-family:"Segoe UI","sans-serif";color:black"><o:p></o:p></span></p>
<p class="MsoNormal" style="background:white"><span style="font-size:11.0pt;font-family:"Segoe UI","sans-serif";color:#1F497D">If I understood you correctly, I should replace some of these entries with “metadata !{null}”. Is this what you meant?</span><span style="font-size:10.0pt;font-family:"Segoe UI","sans-serif";color:black"><o:p></o:p></span></p>
<p class="MsoNormal" style="background:white"><span style="font-size:11.0pt;font-family:"Segoe UI","sans-serif";color:#1F497D"> </span><span style="font-size:10.0pt;font-family:"Segoe UI","sans-serif";color:black"><o:p></o:p></span></p>
<p class="MsoNormal" style="background:white"><span style="font-size:11.0pt;font-family:"Segoe UI","sans-serif";color:#1F497D">The compiler is asserting if I substitute</span><span style="font-size:10.0pt;font-family:"Segoe UI","sans-serif";color:black"><o:p></o:p></span></p>
<p class="MsoNormal" style="background:white"><span style="font-size:11.0pt;font-family:"Segoe UI","sans-serif";color:#1F497D">!63 = metadata !{i32 786689, null, metadata !"value", null, i32 33554439, null, i32 0, null} ; [ DW_TAG_arg_variable ] [value] [line
7]</span><span style="font-size:10.0pt;font-family:"Segoe UI","sans-serif";color:black"><o:p></o:p></span></p>
<p class="MsoNormal" style="background:white"><span style="font-size:11.0pt;font-family:"Segoe UI","sans-serif";color:#1F497D">with</span><span style="font-size:10.0pt;font-family:"Segoe UI","sans-serif";color:black"><o:p></o:p></span></p>
<p class="MsoNormal" style="background:white"><span style="font-size:11.0pt;font-family:"Segoe UI","sans-serif";color:#1F497D">!63 = metadata !{null} ;</span><span style="font-size:10.0pt;font-family:"Segoe UI","sans-serif";color:black"><o:p></o:p></span></p>
<p class="MsoNormal" style="background:white"><span style="font-size:11.0pt;font-family:"Segoe UI","sans-serif";color:#1F497D"> </span><span style="font-size:10.0pt;font-family:"Segoe UI","sans-serif";color:black"><o:p></o:p></span></p>
<p class="MsoNormal" style="background:white"><span style="font-size:11.0pt;font-family:"Segoe UI","sans-serif";color:#1F497D">The test started to pass (i.e. the same code generated at –O2 –g vs -O2), after I substituted</span><span style="font-size:10.0pt;font-family:"Segoe UI","sans-serif";color:black"><o:p></o:p></span></p>
<p class="MsoNormal" style="background:white"><span style="font-size:11.0pt;font-family:"Segoe UI","sans-serif";color:#1F497D">!60 = metadata !{i32 786689, null, metadata !"this", null, i32 16777216, null, i32 1088, null} ; [ DW_TAG_arg_variable ] [this] [line
0]</span><span style="font-size:10.0pt;font-family:"Segoe UI","sans-serif";color:black"><o:p></o:p></span></p>
<p class="MsoNormal" style="background:white"><span style="font-size:11.0pt;font-family:"Segoe UI","sans-serif";color:#1F497D">with</span><span style="font-size:10.0pt;font-family:"Segoe UI","sans-serif";color:black"><o:p></o:p></span></p>
<p class="MsoNormal" style="background:white"><span style="font-size:11.0pt;font-family:"Segoe UI","sans-serif";color:#1F497D">!60 = metadata !{null} ;</span><span style="font-size:10.0pt;font-family:"Segoe UI","sans-serif";color:black"><o:p></o:p></span></p>
<p class="MsoNormal" style="background:white"><span style="font-size:11.0pt;font-family:"Segoe UI","sans-serif";color:#1F497D"> </span><span style="font-size:10.0pt;font-family:"Segoe UI","sans-serif";color:black"><o:p></o:p></span></p>
<p class="MsoNormal" style="background:white"><span style="font-size:11.0pt;font-family:"Segoe UI","sans-serif";color:#1F497D">Replacing any of the 7 metadata entries with metadata !{null} ; either caused the test to produce the same code at –O2 –g/-O2 or caused
the assertion failure. Please let me know if you meant to reduce the test in some other way.</span><span style="font-size:10.0pt;font-family:"Segoe UI","sans-serif";color:black"><o:p></o:p></span></p>
<p class="MsoNormal" style="background:white"><span style="font-size:11.0pt;font-family:"Segoe UI","sans-serif";color:#1F497D"> </span><span style="font-size:10.0pt;font-family:"Segoe UI","sans-serif";color:black"><o:p></o:p></span></p>
<p class="MsoNormal" style="background:white"><span style="font-size:11.0pt;font-family:"Segoe UI","sans-serif";color:#1F497D">Thanks!</span><span style="font-size:10.0pt;font-family:"Segoe UI","sans-serif";color:black"><o:p></o:p></span></p>
<p class="MsoNormal" style="background:white"><span style="font-size:11.0pt;font-family:"Segoe UI","sans-serif";color:#1F497D">Katya.</span><span style="font-size:10.0pt;font-family:"Segoe UI","sans-serif";color:black"><o:p></o:p></span></p>
<p class="MsoNormal" style="background:white"><b><span style="font-size:10.0pt;font-family:"Segoe UI","sans-serif";color:black"> </span></b><span style="font-size:10.0pt;font-family:"Segoe UI","sans-serif";color:black"><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>
<p class="MsoNormal"><span style="font-size:11.0pt;font-family:"Calibri","sans-serif";color:#1F497D"><o:p> </o:p></span></p>
<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""> chandlerc@google.com [mailto:chandlerc@google.com]
<b>On Behalf Of </b>Chandler Carruth<br>
<b>Sent:</b> Thursday, March 13, 2014 5:02 PM<br>
<b>To:</b> reviews+D2970+public+de5bc9734a467b4e@llvm-reviews.chandlerc.com<br>
<b>Cc:</b> Chandler Carruth; Romanova, Katya; Commit Messages and Patches for LLVM<br>
<b>Subject:</b> Re: [PATCH] Branch folding causes different code generation at "-O2 -g" and "-O2"<o:p></o:p></span></p>
<p class="MsoNormal"><o:p> </o:p></p>
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<p class="MsoNormal"><o:p> </o:p></p>
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<p class="MsoNormal">On Thu, Mar 13, 2014 at 4:16 PM, Katya Romanova <<a href="mailto:Katya_Romanova@playstation.sony.com" target="_blank">Katya_Romanova@playstation.sony.com</a>> wrote:<o:p></o:p></p>
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<p class="MsoNormal"> Hi Chandler,<br>
This bugfix is still sitting in my queue. Is it OK to commit? If you are busy, maybe Eric could review?<br>
<br>
I will make a small change to the testcase before I commit. I will add -mtriple-x86_64-linux to the RUN line.<br>
<br>
Thank you!<o:p></o:p></p>
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<p class="MsoNormal"><br>
Please minimize the test case according to this comment I made previously:<o:p></o:p></p>
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<p class="MsoNormal"><o:p> </o:p></p>
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<blockquote style="border:none;border-left:solid #CCCCCC 1.0pt;padding:0in 0in 0in 6.0pt;margin-left:4.8pt;margin-right:0in">
<p class="MsoNormal"><span style="font-size:10.0pt;font-family:"Arial","sans-serif"">I don't think we need a full debug-info test case here.<br>
Just put some stub debug_value calls into the test in the appropriate places with null metadata. It should still work just as well and won't require the full Clang-generated DWARF-structured debug info metadata.</span><o:p></o:p></p>
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