<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=""><div><blockquote type="cite" class=""><div class="">On Nov 10, 2016, at 5:15 PM, Robinson, Paul 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"></blockquote><blockquote type="cite" class=""><span style="color: rgb(31, 73, 125); font-family: Calibri, sans-serif; font-size: 14.666666984558105px;" class="">Back in the day, we called this a BLT (block transfer, pronouced 'blit') for the PDP-10 instruction of that name.</span></blockquote><br class=""></div><div>On x86, there is REP MOVS.</div><div><font color="#1f497d" face="Calibri, sans-serif" class=""><span style="font-size: 14.666666984558105px;" class=""><br class=""></span></font><blockquote type="cite" class=""><div class=""><span style="color: rgb(31, 73, 125); font-family: Calibri, sans-serif; font-size: 14.666666984558105px; 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; display: inline !important; float: none;" class="">You can do this by assigning the first value, then do an overlapping memcpy to fill in the rest.</span></div></blockquote></div><br class=""><div class="">This is undefined behavior, and really doesn’t work with most modern memcpy( ) implementations (the most common thing these days is to simply implement memmove( ) semantics for memcpy, which will very much not do what you want).</div><div class=""><br class=""></div><div class="">– Steve</div></body></html>