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</o:shapelayout></xml><![endif]--></head><body lang=EN-US link=blue vlink=purple><div class=WordSection1><p class=MsoNormal><span style='font-size:11.0pt;font-family:"Calibri","sans-serif";color:#1F497D'>I slip the patch in 2 and checked them in.<o:p></o:p></span></p><p class=MsoNormal><span style='font-size:11.0pt;font-family:"Calibri","sans-serif";color:#1F497D'>We need both, cortex-a53 has one MAC unit.<o:p></o:p></span></p><p class=MsoNormal><span style='font-size:11.0pt;font-family:"Calibri","sans-serif";color:#1F497D'><o:p> </o:p></span></p><p class=MsoNormal><span style='font-size:11.0pt;font-family:"Calibri","sans-serif";color:#1F497D'>Thanks,<o:p></o:p></span></p><p class=MsoNormal><span style='font-size:11.0pt;font-family:"Calibri","sans-serif";color:#1F497D'>Ana.<o:p></o:p></span></p><p class=MsoNormal><span style='font-size:11.0pt;font-family:"Calibri","sans-serif";color:#1F497D'><o:p> </o:p></span></p><p class=MsoNormal><b><span style='font-size:10.0pt;font-family:"Tahoma","sans-serif"'>From:</span></b><span style='font-size:10.0pt;font-family:"Tahoma","sans-serif"'> Jiangning Liu [mailto:liujiangning1@gmail.com] <br><b>Sent:</b> Sunday, December 22, 2013 11:15 PM<br><b>To:</b> Ana Pazos<br><b>Cc:</b> llvm-commits@cs.uiuc.edu for LLVM; Tim Northover<br><b>Subject:</b> Re: [PATCH][AARCH64] Fixed fused multiply add/sub patterns<o:p></o:p></span></p><p class=MsoNormal><o:p> </o:p></p><div><div><p class=MsoNormal><span style='font-family:"Arial","sans-serif"'>Hi Ana,<o:p></o:p></span></p></div><div><p class=MsoNormal><span style='font-family:"Arial","sans-serif"'><o:p> </o:p></span></p></div><div><p class=MsoNormal><span style='font-family:"Arial","sans-serif"'>The fix for fnmadd/fnmsub is OK for me.<o:p></o:p></span></p></div><div><p class=MsoNormal><span style='font-family:"Arial","sans-serif"'><o:p> </o:p></span></p></div><div><p class=MsoNormal><span style='font-family:"Arial","sans-serif"'>But for single_use change, I'm not sure if the following claim is correct, and it depends on hardware implementation, right?<o:p></o:p></span></p></div><div><div><blockquote style='border:none;border-left:solid #CCCCCC 1.0pt;padding:0in 0in 0in 6.0pt;margin-left:4.8pt;margin-right:0in'><div><div><p>AArch64 targets most probably have one MAC pipe and this will be a performance issue as well.<o:p></o:p></p></div></div></blockquote><div><p class=MsoNormal><span style='font-family:"Arial","sans-serif"'>So I think at least it would be better to get them decoupled and upstreamed with two separate patches. If we find any mistake in future, it would be easy for us to roll back as well. Also this optimization could probably depends on different aarch64 target.<o:p></o:p></span></p></div><div><p class=MsoNormal><span style='font-family:"Arial","sans-serif"'><o:p> </o:p></span></p></div><div><p class=MsoNormal><span style='font-family:"Arial","sans-serif"'>Thanks,<o:p></o:p></span></p></div><div><p class=MsoNormal><span style='font-family:"Arial","sans-serif"'>-Jiangning<o:p></o:p></span></p></div></div></div></div></div></body></html>