<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=""><blockquote type="cite" class="">On Aug 29, 2018, at 1:22 PM, Cameron McInally via llvm-dev <<a href="mailto:llvm-dev@lists.llvm.org" class="">llvm-dev@lists.llvm.org</a>> wrote:<br class=""></blockquote><div><blockquote type="cite" class=""><div class=""><div style="caret-color: rgb(0, 0, 0); font-family: Helvetica; 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; text-decoration: none; font-size: 12.800000190734863px;" class=""><br class="Apple-interchange-newline">FSUB(-0.0, NaN) = NaN</div><div style="caret-color: rgb(0, 0, 0); font-family: Helvetica; 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; text-decoration: none; font-size: 12.800000190734863px;" class="">FSUB(-0.0, -NaN) = NaN</div></div></blockquote></div><br class=""><div class="">Some specific architecture may define this, or APFloat might, but IEEE 754 does not interpret the sign of NaN except in four operations (copy, abs, negate, copysign), so it doesn’t say anything about these.</div><div class=""><br class=""></div><div class="">– Steve</div></body></html>