<html><head><meta http-equiv="Content-Type" content="text/html charset=utf-8"></head><body style="word-wrap: break-word; -webkit-nbsp-mode: space; -webkit-line-break: after-white-space;" class=""><br class=""><div><blockquote type="cite" class=""><div class="">On Jun 18, 2016, at 10:44 PM, Yuxi Chen via llvm-dev <<a href="mailto:llvm-dev@lists.llvm.org" class="">llvm-dev@lists.llvm.org</a>> wrote:</div><br class="Apple-interchange-newline"><div class=""><div style="font-style: normal; font-variant-caps: normal; font-weight: normal; letter-spacing: normal; orphans: auto; text-align: start; text-indent: 0px; text-transform: none; white-space: normal; widows: auto; word-spacing: 0px; -webkit-text-stroke-width: 0px; direction: ltr; font-family: Tahoma; font-size: 10pt;" class="">Hi All, <div class=""><br class=""></div><div class="">When I use llvm, I encounter a problem like "unable to schedule pass A required by C"</div><div class="">I investigated deeper. It's like:</div><div class="">I have three passes, say A, B, C(all are on function level)</div><div class="">A would modify IR code. (change instruction order)</div><div class=""><br class=""></div><div class="">For pass B, </div><div class="">I would use the result of pass A, I use addRequired<B>(), and &getAnalysis<B>(), it works. </div><div class=""><br class=""></div><div class="">void getAnalysisUsage(AU){</div><div class=""><span class="Apple-tab-span" style="white-space: pre;"></span>AU.addRequired<A>();</div><div class="">}</div><div class=""><br class=""></div><div class=""><br class=""></div><div class="">For pass C, it will use the results of pass A and B. </div><div class="">I use the way as used for pass B, but it failed, even for LoopInfo analysis pass(which is the built-in analysis pass).</div><div class="">void getAnalysisUsage(AU){</div><div class=""><span style="font-size: 10pt;" class=""><span class="Apple-tab-span" style="white-space: pre;"></span>AU.addRequired<A>();</span></div><div class=""><span style="font-size: 10pt;" class=""><span class="Apple-tab-span" style="white-space: pre;"></span>AU.addRequired<B>();</span></div><div class=""><span style="font-size: 10pt;" class="">}</span></div><div class=""><br class=""></div><div class=""><br class=""></div><div class="">It seems because A would modify IR code, so for pass C, I need first load pass A then pass B, otherwise it will be invalidated. </div><div class="">However, when I change the using order, I still got error "unable to schedule pass A required by C".</div><div class=""><br class=""></div><div class="">Does anyone encounter the same problem before and have a solution?</div></div></div></blockquote><blockquote type="cite" class=""><div class=""><div style="font-style: normal; font-variant-caps: normal; font-weight: normal; letter-spacing: normal; orphans: auto; text-align: start; text-indent: 0px; text-transform: none; white-space: normal; widows: auto; word-spacing: 0px; -webkit-text-stroke-width: 0px; direction: ltr; font-family: Tahoma; font-size: 10pt;" class=""><div class="">Any help is appreciated. </div></div></div></blockquote><div><br class=""></div><div>Depending on other transformations isn’t recommended, and isn’t supported by the soon-new-passmanager I believe.</div><div>The expectation is that the passes are added in order to the pass manager by the client.</div><div><br class=""></div><div>In you case, I expect that it would “work” by removing the dependency from C to A. If C requires B and B requires A, by scheduling C you’ll get A, B, C in sequence.</div><div><br class=""></div><div>— </div><div>Mehdi</div><div><br class=""></div><div><br class=""></div><br class=""><blockquote type="cite" class=""><div class=""><div style="font-style: normal; font-variant-caps: normal; font-weight: normal; letter-spacing: normal; orphans: auto; text-align: start; text-indent: 0px; text-transform: none; white-space: normal; widows: auto; word-spacing: 0px; -webkit-text-stroke-width: 0px; direction: ltr; font-family: Tahoma; font-size: 10pt;" class=""><div class=""><br class=""></div><div class="">Best,</div><div class="">Yuxi</div></div><span style="font-family: Helvetica; font-size: 12px; font-style: normal; font-variant-caps: normal; font-weight: normal; letter-spacing: normal; orphans: auto; text-align: start; text-indent: 0px; text-transform: none; white-space: normal; widows: auto; word-spacing: 0px; -webkit-text-stroke-width: 0px; float: none; display: inline !important;" class="">_______________________________________________</span><br style="font-family: Helvetica; font-size: 12px; font-style: normal; font-variant-caps: normal; font-weight: normal; letter-spacing: normal; orphans: auto; text-align: start; text-indent: 0px; text-transform: none; white-space: normal; widows: auto; word-spacing: 0px; -webkit-text-stroke-width: 0px;" class=""><span style="font-family: Helvetica; font-size: 12px; font-style: normal; font-variant-caps: normal; font-weight: normal; letter-spacing: normal; orphans: auto; text-align: start; text-indent: 0px; text-transform: none; white-space: normal; widows: auto; word-spacing: 0px; -webkit-text-stroke-width: 0px; float: none; display: inline !important;" class="">LLVM Developers mailing list</span><br style="font-family: Helvetica; font-size: 12px; font-style: normal; font-variant-caps: normal; font-weight: normal; letter-spacing: normal; orphans: auto; text-align: start; text-indent: 0px; text-transform: none; white-space: normal; widows: auto; word-spacing: 0px; -webkit-text-stroke-width: 0px;" class=""><a href="mailto:llvm-dev@lists.llvm.org" style="font-family: Helvetica; font-size: 12px; font-style: normal; font-variant-caps: normal; font-weight: normal; letter-spacing: normal; orphans: auto; text-align: start; text-indent: 0px; text-transform: none; white-space: normal; widows: auto; word-spacing: 0px; -webkit-text-size-adjust: auto; -webkit-text-stroke-width: 0px;" class="">llvm-dev@lists.llvm.org</a><br style="font-family: Helvetica; font-size: 12px; font-style: normal; font-variant-caps: normal; font-weight: normal; letter-spacing: normal; orphans: auto; text-align: start; text-indent: 0px; text-transform: none; white-space: normal; widows: auto; word-spacing: 0px; -webkit-text-stroke-width: 0px;" class=""><a href="http://lists.llvm.org/cgi-bin/mailman/listinfo/llvm-dev" style="font-family: Helvetica; font-size: 12px; font-style: normal; font-variant-caps: normal; font-weight: normal; letter-spacing: normal; orphans: auto; text-align: start; text-indent: 0px; text-transform: none; white-space: normal; widows: auto; word-spacing: 0px; -webkit-text-size-adjust: auto; -webkit-text-stroke-width: 0px;" class="">http://lists.llvm.org/cgi-bin/mailman/listinfo/llvm-dev</a></div></blockquote></div><br class=""></body></html>