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</o:shapelayout></xml><![endif]--></head><body bgcolor=white lang=EN-IE link=blue vlink=purple><div class=WordSection1><p class=MsoNormal><span style='font-family:"Book Antiqua",serif;color:#993366;mso-fareast-language:EN-US'>Thanks Eli,<o:p></o:p></span></p><p class=MsoNormal><span style='font-family:"Book Antiqua",serif;color:#993366;mso-fareast-language:EN-US'><o:p> </o:p></span></p><p class=MsoNormal><span style='font-family:"Book Antiqua",serif;color:#993366;mso-fareast-language:EN-US'>My edits are just experiments to see if I could fix it, but I am not familiar with this area of the code and my approach is inevitably naïve.<o:p></o:p></span></p><p class=MsoNormal><span style='font-family:"Book Antiqua",serif;color:#993366;mso-fareast-language:EN-US'><o:p> </o:p></span></p><p class=MsoNormal><span style='font-family:"Book Antiqua",serif;color:#993366;mso-fareast-language:EN-US'>All the best,<o:p></o:p></span></p><p class=MsoNormal><span style='font-family:"Book Antiqua",serif;color:#993366;mso-fareast-language:EN-US'><o:p> </o:p></span></p><p class=MsoNormal><span style='font-family:"Book Antiqua",serif;color:#993366;mso-fareast-language:EN-US'> MartinO<o:p></o:p></span></p><p class=MsoNormal><span style='font-family:"Book Antiqua",serif;color:#993366;mso-fareast-language:EN-US'><o:p> </o:p></span></p><div><div style='border:none;border-top:solid #E1E1E1 1.0pt;padding:3.0pt 0cm 0cm 0cm'><p class=MsoNormal><b><span lang=EN-US style='font-size:11.0pt;font-family:"Calibri",sans-serif;color:windowtext'>From:</span></b><span lang=EN-US style='font-size:11.0pt;font-family:"Calibri",sans-serif;color:windowtext'> Friedman, Eli [mailto:efriedma@codeaurora.org] <br><b>Sent:</b> 20 September 2016 18:14<br><b>To:</b> Martin J. O'Riordan <martin.oriordan@movidius.com>; mehdi.amini@apple.com<br><b>Cc:</b> 'LLVM Developers' <llvm-dev@lists.llvm.org><br><b>Subject:</b> Re: [llvm-dev] LLVM v3.9.0 and math built-ins<o:p></o:p></span></p></div></div><p class=MsoNormal><o:p> </o:p></p><div><p class=MsoNormal>On 9/20/2016 4:12 AM, Martin J. O'Riordan via llvm-dev wrote:<o:p></o:p></p></div><blockquote style='margin-top:5.0pt;margin-bottom:5.0pt'><p class=MsoNormal>I modified my sources to force ‘readnone’ and even tried ‘setDoesNotAccessMemory()’ on the math functions, but this still results in one call occurring and the code generated is effectively:<o:p></o:p></p><p class=MsoNormal> <o:p></o:p></p><p class=MsoNormal style='margin-left:36.0pt'>(void)exp(1.0);<o:p></o:p></p><p class=MsoNormal style='margin-left:36.0pt'>return 0;<o:p></o:p></p><p class=MsoNormal> <o:p></o:p></p><p class=MsoNormal style='margin-left:36.0pt'><span style='font-size:10.0pt'> %1 = tail call float @exp(float 1.000000e+00)</span><o:p></o:p></p><p class=MsoNormal style='margin-left:36.0pt'><span style='font-size:10.0pt'> </span><o:p></o:p></p><p class=MsoNormal style='margin-left:36.0pt'><span style='font-size:10.0pt'>; Function Attrs: readnone</span><o:p></o:p></p><p class=MsoNormal style='margin-left:36.0pt'><span style='font-size:10.0pt'>declare float @exp(float) local_unnamed_addr #1</span><o:p></o:p></p></blockquote><p class=MsoNormal><br>You have to set readonly on the call, not the function ("<span style='font-size:10.0pt'>tail call float @exp(float 1.000000e+00) readonly"</span>) ; the attributes on a function declaration are generally ignored by LLVM.<br><br><br>For the difference between 3.8 and 3.9, see <a href="https://llvm.org/bugs/show_bug.cgi?id=30464">https://llvm.org/bugs/show_bug.cgi?id=30464</a> .<br><br>-Eli<br><br><o:p></o:p></p><pre>-- <o:p></o:p></pre><pre>Employee of Qualcomm Innovation Center, Inc.<o:p></o:p></pre><pre>Qualcomm Innovation Center, Inc. is a member of Code Aurora Forum, a Linux Foundation Collaborative Project<o:p></o:p></pre></div></body></html>