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<p class="MsoNormal">Dear Community,<o:p></o:p></p>
<p class="MsoNormal"><o:p> </o:p></p>
<p class="MsoNormal">I'm trying to implement optimization described in PR26223 and meet the following bail out condition in CodeGenPrepare::optimizeMemoryInst.<o:p></o:p></p>
<p class="MsoNormal"><o:p> </o:p></p>
<p class="MsoNormal"> // Break use-def graph loops.<o:p></o:p></p>
<p class="MsoNormal"> if (!Visited.insert(V).second) {<o:p></o:p></p>
<p class="MsoNormal"> Consensus = nullptr;<o:p></o:p></p>
<p class="MsoNormal"> break;<o:p></o:p></p>
<p class="MsoNormal"> }<o:p></o:p></p>
<p class="MsoNormal"><o:p> </o:p></p>
<p class="MsoNormal">So while traversing thorough phi nodes from memory instruction to find addr mode we bail out if we meet some instruction twice.<o:p></o:p></p>
<p class="MsoNormal">Does anybody know/remember what is the reason for this checks.<o:p></o:p></p>
<p class="MsoNormal">From the first glance it seems that it will be ok if we just mark it as visited and continue processing worklist.<o:p></o:p></p>
<p class="MsoNormal">I did this change and make check passed. <o:p></o:p></p>
<p class="MsoNormal"><o:p> </o:p></p>
<p class="MsoNormal">So I seek for a help to explain this decision.<o:p></o:p></p>
<p class="MsoNormal"><o:p> </o:p></p>
<p class="MsoNormal">Thank you in advance,<o:p></o:p></p>
<p class="MsoNormal">Serguei.<o:p></o:p></p>
<p class="MsoNormal"><span lang="RU"><o:p> </o:p></span></p>
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