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</o:shapelayout></xml><![endif]--></head><body lang=EN-GB link=blue vlink=purple><div class=WordSection1><p class=MsoNormal><span style='color:#1F497D'>Yes, for now the spilling is done in the most basic way, i.e. it’s functionally correct --- but not efficient. The focus was on the allocator itself, not on the spilling. As you noticed, the work still to be done in this area is live range splitting, and smarter spill code insertion. Another area is improving the reduction order, to make the allocator less sensitive to the reduction order.<o:p></o:p></span></p><p class=MsoNormal><span style='color:#1F497D'><o:p> </o:p></span></p><p class=MsoNormal><span style='color:#1F497D'>There is no official plan; we started to discuss that with Lang some time ago, but none of us had time to dive into it yet. Any help appreciated there </span><span style='font-family:Wingdings;color:#1F497D'>J</span><span style='color:#1F497D'>.<o:p></o:p></span></p><p class=MsoNormal><span style='color:#1F497D'><o:p> </o:p></span></p><p class=MsoNormal><span style='color:#1F497D'>Cheers,<o:p></o:p></span></p><p class=MsoNormal><span style='color:#1F497D'>Arnaud<o:p></o:p></span></p><p class=MsoNormal><span style='color:#1F497D'><o:p> </o:p></span></p><div style='border:none;border-left:solid blue 1.5pt;padding:0cm 0cm 0cm 4.0pt'><div><div style='border:none;border-top:solid #B5C4DF 1.0pt;padding:3.0pt 0cm 0cm 0cm'><p class=MsoNormal><b><span lang=EN-US style='font-size:10.0pt;font-family:"Tahoma","sans-serif"'>From:</span></b><span lang=EN-US style='font-size:10.0pt;font-family:"Tahoma","sans-serif"'> Jonas Paulsson [mailto:jonas.paulsson@ericsson.com] <br><b>Sent:</b> 04 March 2015 13:51<br><b>To:</b> Lang Hames; Arnaud De Grandmaison<br><b>Cc:</b> llvmdev@cs.uiuc.edu<br><b>Subject:</b> PBQP spilling<o:p></o:p></span></p></div></div><p class=MsoNormal><o:p> </o:p></p><p class=MsoNormal><span lang=EN-US>Hi,<o:p></o:p></span></p><p class=MsoNormal><span lang=EN-US><o:p> </o:p></span></p><p class=MsoNormal><span lang=EN-US>I would like to ask about PBQPs use of InlineSpiller. The code output when using PBQP gets a lot bigger compared to when using RegAllocGreedy. PBQP does not split the live intervals, and a lot more (often redundant) reload instructions are emitted as a result, it seems. I wonder why this is, and if there are any plans to improve on this point? <o:p></o:p></span></p><p class=MsoNormal><span lang=EN-US><o:p> </o:p></span></p><p class=MsoNormal><span lang=EN-US>/Jonas Paulsson<o:p></o:p></span></p><p class=MsoNormal><span lang=EN-US><o:p> </o:p></span></p></div></div></body></html>