<html><head><meta http-equiv="Content-Type" content="text/html; charset=utf-8"></head><body style="word-wrap: break-word; -webkit-nbsp-mode: space; line-break: after-white-space;" class="">On Feb 28, 2018, at 3:29 PM, Kaylor, Andrew via llvm-dev <<a href="mailto:llvm-dev@lists.llvm.org" class="">llvm-dev@lists.llvm.org</a>> wrote:<br class=""><div><blockquote type="cite" class=""><div class=""><div class="WordSection1" style="page: WordSection1; font-family: Helvetica; font-size: 12px; font-style: normal; font-variant-caps: normal; font-weight: normal; letter-spacing: normal; text-align: start; text-indent: 0px; text-transform: none; white-space: normal; word-spacing: 0px; -webkit-text-stroke-width: 0px; background-color: rgb(255, 255, 255);"><div style="margin: 0in 0in 0.0001pt; font-size: 12pt; font-family: "Times New Roman", serif;" class=""><span style="font-size: 11pt; font-family: Calibri, sans-serif; color: rgb(31, 73, 125);" class="">For the first part of Sanjay’s question, I think the answer is, “Yes, we can fold all of these to NaN in the general case.” </span></div></div></div></blockquote><div><br class=""></div><div>Agreed. Those IR instructions are undefined on SNAN, and that undef could take on an SNAN value. Folding these instructions to undef seems reasonable, and it is arguable that you could even fold it to an ‘unreachable'.</div><div><br class=""></div><div>-Chris</div><div><br class=""></div></div></body></html>