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<p class="MsoNormal">Hello,<o:p></o:p></p>
<p class="MsoNormal"><o:p> </o:p></p>
<p class="MsoNormal">I hit a problem which seems related to followup loop attribute.<o:p></o:p></p>
<p class="MsoNormal">The testcase is like:<o:p></o:p></p>
<p class="MsoNormal"><o:p> </o:p></p>
<p class="MsoNormal"><span style="font-size:9.0pt;font-family:"Courier New"">for (…) {<o:p></o:p></span></p>
<p class="MsoNormal"><span style="font-size:9.0pt;font-family:"Courier New""> #pragma clang loop vectorize(enable) unroll_count(4)<o:p></o:p></span></p>
<p class="MsoNormal"><span style="font-size:9.0pt;font-family:"Courier New""> for (…) {<o:p></o:p></span></p>
<p class="MsoNormal" style="text-indent:9.75pt"><span style="font-size:9.0pt;font-family:"Courier New"">…<o:p></o:p></span></p>
<p class="MsoNormal"><span style="font-size:9.0pt;font-family:"Courier New""> }<o:p></o:p></span></p>
<p class="MsoNormal"><span style="font-size:9.0pt;font-family:"Courier New"">}<o:p></o:p></span></p>
<p class="MsoNormal"><span style="font-size:9.0pt;font-family:"Courier New""><o:p> </o:p></span></p>
<p class="MsoNormal">Before loop vectorization, the Metadata is like:<o:p></o:p></p>
<p class="MsoNormal"><span style="font-size:9.0pt;font-family:"Courier New"">!7 = distinct !{!7, !8} <== LOOP<o:p></o:p></span></p>
<p class="MsoNormal"><span style="font-size:9.0pt;font-family:"Courier New"">!8 = distinct !{!8, !9, !10}<o:p></o:p></span></p>
<p class="MsoNormal"><span style="font-size:9.0pt;font-family:"Courier New"">!9 = !{!"llvm.loop.isvectorized"}<o:p></o:p></span></p>
<p class="MsoNormal"><span style="font-size:9.0pt;font-family:"Courier New"">!10 = !{!"llvm.loop.unroll.count", i32 4}<o:p></o:p></span></p>
<p class="MsoNormal"><span style="font-size:9.0pt;font-family:"Courier New"">!11 = distinct !{!11, !12, !13} <== LOOP<o:p></o:p></span></p>
<p class="MsoNormal"><span style="font-size:9.0pt;font-family:"Courier New"">!12 = !{!"llvm.loop.vectorize.enable", i1 true}<o:p></o:p></span></p>
<p class="MsoNormal"><span style="font-size:9.0pt;font-family:"Courier New"">!13 = !{!"llvm.loop.vectorize.followup_all", !8}<o:p></o:p></span></p>
<p class="MsoNormal"><span style="font-size:9.0pt;font-family:"Courier New""><o:p> </o:p></span></p>
<p class="MsoNormal">After loop vectorization, the Metadata is:<o:p></o:p></p>
<p class="MsoNormal"><span style="font-size:9.0pt;font-family:"Courier New"">!7 = distinct !{!7, !8}<o:p></o:p></span></p>
<p class="MsoNormal"><span style="font-size:9.0pt;font-family:"Courier New"">!8 = distinct !{!8, !9, !10}<o:p></o:p></span></p>
<p class="MsoNormal"><span style="font-size:9.0pt;font-family:"Courier New"">!9 = !{!"llvm.loop.isvectorized"}<o:p></o:p></span></p>
<p class="MsoNormal"><span style="font-size:9.0pt;font-family:"Courier New"">!10 = !{!"llvm.loop.unroll.count", i32 4}<o:p></o:p></span></p>
<p class="MsoNormal"><span style="font-size:9.0pt;font-family:"Courier New"">!11 = distinct !{!11, !8, !12}<o:p></o:p></span></p>
<p class="MsoNormal"><span style="font-size:9.0pt;font-family:"Courier New"">!12 = !{!"llvm.loop.isvectorized", i32 1}<o:p></o:p></span></p>
<p class="MsoNormal"><span style="font-size:9.0pt;font-family:"Courier New""><o:p> </o:p></span></p>
<p class="MsoNormal">During loop unrolling, the compiler cannot find the “llvm.loop.unroll.count” pragama value (either from !7 or !11) since the value is one level down. Is there any existing solution for this or it is a known issue?<o:p></o:p></p>
<p class="MsoNormal"><o:p> </o:p></p>
<p class="MsoNormal"><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">Yan<o:p></o:p></p>
<p class="MsoNormal"><span style="font-size:9.0pt;font-family:"Courier New""><o:p> </o:p></span></p>
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