<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="">Hey Anna,<div class=""><br class=""><div><blockquote type="cite" class=""><div class="">On Sep 30, 2016, at 2:46 PM, Anna Thomas <<a href="mailto:anna@azul.com" class="">anna@azul.com</a>> wrote:</div><br class="Apple-interchange-newline"><div class="">
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Hi Mehdi,
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<div class="">On Sep 30, 2016, at 4:27 PM, Mehdi Amini <<a href="mailto:mehdi.amini@apple.com" class="">mehdi.amini@apple.com</a>> wrote:</div>
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<blockquote type="cite" class="">On Sep 30, 2016, at 12:37 PM, Anna Thomas via llvm-dev <<a href="mailto:llvm-dev@lists.llvm.org" class="">llvm-dev@lists.llvm.org</a>> wrote:<br class="">
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Hi,<br class="">
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I was wondering what’s the community guideline for adding new passes which are solely used for debugging/analysis purposes? Can this be in the upstream llvm, or such passes are more suitable in local downstream repository?<br class="">
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In our case, the ‘utility (ease-of-analysis)’ pass is for transformation done by RewriteStatepointsForGC (RS4GC). Note that right now, RS4GC is not enabled in the opt pipeline upstream, but the utility pass would be for downstream users who have RS4GC enabled
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I think you should start by describing exactly what the pass is doing and how it is useful for working with/on RewriteStatepointsForGC.<br class="">
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<div class="">The pass will remove all the gc.relocates that are inserted by RewriteStatepoints. This is solely useful for analysis purposes of the final optimized IR (with RS4GC in place), when the IR is too polluted with gc.relocates of the original pointers.
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<div class="">More details at: <a href="https://reviews.llvm.org/D25096" class="">https://reviews.llvm.org/D25096</a></div>
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<div class="">The scenario where this is useful: There is a performance regression and analyzing through the final IR is too tedious because of all the gc.relocates. </div>
<div class="">This pass would take the optimized IR, and remove the gc.relocates. This will enable easier manual traversal through IR (without having to worry about the gc.relocates). </div>
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</div></div></div></div></div></blockquote></div><br class=""></div><div class="">This seems fine to me to be in-tree on the principle. </div><div class=""><br class=""></div><div class="">But let’s hear about others…</div><div class=""><br class=""></div><div class=""><br class=""></div><div class="">— </div><div class="">Mehdi</div><div class=""><br class=""></div></body></html>