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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='font-size:11.0pt;font-family:"Calibri","sans-serif";color:#1F497D'>I am not sure I will have time in the next few days, but I am interested in rewriting the patch and learn to use your new metadata infrastructure.<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'>Using a priority queue was what I wanted to do at first </span><span style='font-size:11.0pt;font-family:Wingdings;color:#1F497D'>J</span><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'><o:p> </o:p></span></p><p class=MsoNormal><span style='font-size:11.0pt;font-family:"Calibri","sans-serif";color:#1F497D'>Cheers,<o:p></o:p></span></p><p class=MsoNormal><span style='font-size:11.0pt;font-family:"Calibri","sans-serif";color:#1F497D'>Arnaud<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><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"'> Lang Hames [mailto:lhames@gmail.com] <br><b>Sent:</b> 04 November 2014 19:56<br><b>To:</b> Arnaud De Grandmaison<br><b>Cc:</b> Commit Messages and Patches for LLVM<br><b>Subject:</b> Re: [PATCH 3/3] [PBQP] Enforce a safe order for ConservativelyAllocatableNodes<o:p></o:p></span></p></div></div><p class=MsoNormal><o:p> </o:p></p><div><p class=MsoNormal>Hello Arnaud,<o:p></o:p></p><div><p class=MsoNormal><o:p> </o:p></p></div><div><p class=MsoNormal>This is a good idea, but the implementation in this patch will make removal of conservatively allocatable nodes more expensive: from O(N) to O(RN^2), where R is the number of registers and N is the number of nodes. We can get that back down to O(RN + NlogN) by creating a VectorMetadata class that contains the expected/worst-case cost, and using a set (or better yet, a priority_queue) to hold the conservatively allocatable nodes. This is the same line of reasoning that was applied (very successfully) to MatrixMetadata to bring down the cost for the conservative-allocatability test itself.<o:p></o:p></p></div><div><p class=MsoNormal><o:p> </o:p></p></div><div><p class=MsoNormal>If you're happy to rewrite your patch along those lines please go for it, otherwise I can find some time to do it in the next few days. It is not a big change at all, though it helps that I'm familiar with the infrastructure.<o:p></o:p></p></div><div><p class=MsoNormal><o:p> </o:p></p></div><div><p class=MsoNormal>Cheers,<o:p></o:p></p></div><div><p class=MsoNormal>Lang.<o:p></o:p></p></div><div><p class=MsoNormal> <o:p></o:p></p></div></div><div><p class=MsoNormal><o:p> </o:p></p><div><p class=MsoNormal>On Wed, Oct 22, 2014 at 6:43 AM, Arnaud A. de Grandmaison <<a href="mailto:arnaud.degrandmaison@arm.com" target="_blank">arnaud.degrandmaison@arm.com</a>> wrote:<o:p></o:p></p><div><div><p class=MsoNormal style='mso-margin-top-alt:auto;mso-margin-bottom-alt:auto'>Hi Lang,<o:p></o:p></p><p class=MsoNormal style='mso-margin-top-alt:auto;mso-margin-bottom-alt:auto'> <o:p></o:p></p><p class=MsoNormal style='mso-margin-top-alt:auto;mso-margin-bottom-alt:auto'>Here is the last patch in the PBQP improvement serie. Could you please have a look at it ?<o:p></o:p></p><p class=MsoNormal style='mso-margin-top-alt:auto;mso-margin-bottom-alt:auto'> <o:p></o:p></p><p class=MsoNormal style='mso-margin-top-alt:auto;mso-margin-bottom-alt:auto'>Nodes in ConservativelyAllocatableNodes were processed in the order they<o:p></o:p></p><p class=MsoNormal style='mso-margin-top-alt:auto;mso-margin-bottom-alt:auto'>have been added in NodeSet; however, it is preferable to process nodes in<o:p></o:p></p><p class=MsoNormal style='mso-margin-top-alt:auto;mso-margin-bottom-alt:auto'>an order based on their cost, to ensure we keep the total cost under<o:p></o:p></p><p class=MsoNormal style='mso-margin-top-alt:auto;mso-margin-bottom-alt:auto'>control and provide a reasonable solution.<o:p></o:p></p><p class=MsoNormal style='mso-margin-top-alt:auto;mso-margin-bottom-alt:auto'> <o:p></o:p></p><p class=MsoNormal style='mso-margin-top-alt:auto;mso-margin-bottom-alt:auto'><span lang=FR>Cheers,</span><o:p></o:p></p><p class=MsoNormal style='mso-margin-top-alt:auto;mso-margin-bottom-alt:auto'><span lang=FR>--</span><o:p></o:p></p><p class=MsoNormal style='mso-margin-top-alt:auto;mso-margin-bottom-alt:auto'><span lang=FR>Arnaud A. de Grandmaison</span><o:p></o:p></p><p class=MsoNormal style='mso-margin-top-alt:auto;mso-margin-bottom-alt:auto'><span lang=FR> </span><o:p></o:p></p></div></div></div><p class=MsoNormal><o:p> </o:p></p></div></div></div></body></html>