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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'>Chandler, thank you very much for working on this.<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'>My manual implementation was a) using an extra unnecessary push+pop, and b) resulting in a very twisted and unoptimizable control flow. The one by Jeremy Lakeman is better.<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'>Let me know if I can be of help with benchmarking/tuning for ARM architectures or anything else.<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"'> Chandler Carruth [mailto:chandlerc@google.com] <br><b>Sent:</b> 18 February 2015 21:01<br><b>To:</b> Pablo Barrio<br><b>Cc:</b> Hal Finkel; James Molloy; llvmdev@cs.uiuc.edu<br><b>Subject:</b> Re: RFC: Recursive inlining<o:p></o:p></span></p><p class=MsoNormal><o:p> </o:p></p><div><div><p class=MsoNormal><o:p> </o:p></p><div><p class=MsoNormal>On Wed, Feb 18, 2015 at 12:57 PM, Pablo Barrio <<a href="mailto:Pablo.Barrio@arm.com" target="_blank">Pablo.Barrio@arm.com</a>> wrote:<o:p></o:p></p><p class=MsoNormal>Also, virtually all processors beyond a certain level of sophistication (let's say, meant to run an OS) feature a return-stack prediction mechanism. This results in highly-efficient branch prediction for calls+returns. Since we are transforming the "call jumps" into "switch jumps", we are probably misusing that piece of hardware.<o:p></o:p></p></div><p class=MsoNormal><br>Yes, it will be critical to use a branching pattern that similarly fits modern predictors. I don't think this will be hard though. Again, I'm continuing to work on a prototype actual pass.<o:p></o:p></p></div></div></div></body></html>