<html xmlns:v="urn:schemas-microsoft-com:vml" xmlns:o="urn:schemas-microsoft-com:office:office" xmlns:w="urn:schemas-microsoft-com:office:word" xmlns:m="http://schemas.microsoft.com/office/2004/12/omml" xmlns="http://www.w3.org/TR/REC-html40"><head><META HTTP-EQUIV="Content-Type" CONTENT="text/html; charset=us-ascii"><meta name=Generator content="Microsoft Word 15 (filtered medium)"><style><!--
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</o:shapelayout></xml><![endif]--></head><body lang=EN-US link="#0563C1" vlink="#954F72"><div class=WordSection1><p class=MsoNormal>Hi,<br><br>Thank you for your time in reading this. I need help in analyzing the live-in and live-out variables for few loops in the llvm IR. I want to figure out which is a live-variable at the end of the loop and what is live-in variable for the loop. I found that such provisions are available for machine instructions. But, I have to use this at IR level. I found few papers showing algorithms to construct such analysis but, it seems to me that this must be a problem encountered before and there should be at least similar functionalities in some of the analyses passes in the existing LLVM framework. It would be great if I can find some references or someone can give some suggestions.<br><br>If I cannot find some existing passes, I am also not sure about – how can I make use of Intrinsic::invariant_start or Intrinsic::lifetime_start for aforementioned purpose. Any help is highly appreciated. Thanks!<br><br><o:p></o:p></p><p class=MsoNormal>Best,<br><b><span style='font-size:10.0pt;font-family:"Segoe Script";color:#0D0D0D'>Shail</span></b><span style='font-family:"Segoe Script"'><o:p></o:p></span></p></div></body></html>