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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'>Hi Evan,<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=MsoPlainText>This patch addressed the problem I submitted before. The default<o:p></o:p></p><p class=MsoPlainText>Option has been set to off. A segment of redundant elimination code<o:p></o:p></p><p class=MsoPlainText>has been removed. I will commit the new redundant elimination later<o:p></o:p></p><p class=MsoPlainText>after it becomes available. <o:p></o:p></p><p class=MsoPlainText><o:p> </o:p></p><p class=MsoPlainText>Thanks,<o:p></o:p></p><p class=MsoPlainText><o:p> </o:p></p><p class=MsoPlainText> Yin <o:p></o:p></p><p class=MsoPlainText><o:p> </o:p></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'><o:p> </o:p></span></p><div><div style='border:none;border-top:solid #B5C4DF 1.0pt;padding:3.0pt 0in 0in 0in'><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"'> Evan Cheng [mailto:evan.cheng@apple.com] <br><b>Sent:</b> Wednesday, August 01, 2012 11:12 AM<br><b>To:</b> Yin Ma<br><b>Cc:</b> llvm-commits@cs.uiuc.edu<br><b>Subject:</b> Re: [llvm-commits] [PATCH][Review Please] Optimize ARM Position Independent Code Generation<o:p></o:p></span></p></div></div><p class=MsoNormal><o:p> </o:p></p><p class=MsoNormal>Thanks. This looks like a good change to ELF codegen. I am ok with the isel change.<o:p></o:p></p><div><p class=MsoNormal><o:p> </o:p></p></div><div><p class=MsoNormal>However, I'm not ok with pre-ra load / store optimizer change. It's the wrong place to do it. MachineCSE should be eliminating the unnecessary PIC instructions. You might want to look at Darwin codegen and how it plays with MachineCSE.<o:p></o:p></p></div><div><p class=MsoNormal><o:p> </o:p></p></div><div><p class=MsoNormal>Evan<o:p></o:p></p></div><div><p class=MsoNormal><o:p> </o:p></p><div><div><p class=MsoNormal>On Aug 1, 2012, at 10:24 AM, Yin Ma <<a href="mailto:yinma@codeaurora.org">yinma@codeaurora.org</a>> wrote:<o:p></o:p></p></div><p class=MsoNormal><br><br><o:p></o:p></p><div><div><p class=MsoNormal><span style='font-size:11.0pt;font-family:"Calibri","sans-serif";color:#1F497D'>Hi Evan,</span><o:p></o:p></p></div><div><p class=MsoNormal><span style='font-size:11.0pt;font-family:"Calibri","sans-serif";color:#1F497D'> </span><o:p></o:p></p></div><div><p class=MsoNormal style='text-indent:9.0pt'><span style='font-size:11.0pt;font-family:"Calibri","sans-serif";color:#1F497D'>The attached pdf contains an example of this change. It can result</span><o:p></o:p></p></div><div><p class=MsoNormal style='text-indent:9.0pt'><span style='font-size:11.0pt;font-family:"Calibri","sans-serif";color:#1F497D'>In code size reduction for most of PIC enabled programs.</span><o:p></o:p></p></div><div><p class=MsoNormal><span style='font-size:11.0pt;font-family:"Calibri","sans-serif";color:#1F497D'> </span><o:p></o:p></p></div><div><p class=MsoNormal><span style='font-size:11.0pt;font-family:"Calibri","sans-serif";color:#1F497D'>Thanks,</span><o:p></o:p></p></div><div><p class=MsoNormal><span style='font-size:11.0pt;font-family:"Calibri","sans-serif";color:#1F497D'> </span><o:p></o:p></p></div><div><p class=MsoNormal><span style='font-size:11.0pt;font-family:"Calibri","sans-serif";color:#1F497D'> Yin</span><o:p></o:p></p></div><div><p class=MsoNormal><span style='font-size:11.0pt;font-family:"Calibri","sans-serif";color:#1F497D'> </span><o:p></o:p></p></div><div><div style='border:none;border-top:solid #B5C4DF 1.0pt;padding:3.0pt 0in 0in 0in'><div><p class=MsoNormal><b><span style='font-size:10.0pt;font-family:"Tahoma","sans-serif"'>From:</span></b><span class=apple-converted-space><span style='font-size:10.0pt;font-family:"Tahoma","sans-serif"'> </span></span><span style='font-size:10.0pt;font-family:"Tahoma","sans-serif"'>Evan Cheng [mailto:evan.cheng@<a href="http://apple.com"><span style='color:purple'>apple.com</span></a>]<span class=apple-converted-space> </span><br><b>Sent:</b><span class=apple-converted-space> </span>Tuesday, July 31, 2012 5:48 PM<br><b>To:</b><span class=apple-converted-space> </span>Yin Ma<br><b>Cc:</b><span class=apple-converted-space> </span><a href="mailto:llvm-commits@cs.uiuc.edu"><span style='color:purple'>llvm-commits@cs.uiuc.edu</span></a><br><b>Subject:</b><span class=apple-converted-space> </span>Re: [llvm-commits] [PATCH][Review Please] Optimize ARM Position Independent Code Generation</span><o:p></o:p></p></div></div></div><div><p class=MsoNormal> <o:p></o:p></p></div><div><p class=MsoNormal>Hi Yin,<o:p></o:p></p></div><div><div><p class=MsoNormal> <o:p></o:p></p></div></div><div><div><p class=MsoNormal>Can you provide some assembly code so we can understand what you are trying to do?<o:p></o:p></p></div></div><div><div><p class=MsoNormal> <o:p></o:p></p></div></div><div><div><p class=MsoNormal>Thanks,<o:p></o:p></p></div></div><div><div><p class=MsoNormal> <o:p></o:p></p></div></div><div><div><p class=MsoNormal>Evan<o:p></o:p></p></div></div><div><div><p class=MsoNormal> <o:p></o:p></p></div><div><div><div><p class=MsoNormal>On Jul 30, 2012, at 10:55 AM, Yin Ma <<a href="mailto:yinma@codeaurora.org"><span style='color:purple'>yinma@codeaurora.org</span></a>> wrote:<o:p></o:p></p></div></div><div><p class=MsoNormal><br><br><br><o:p></o:p></p></div><div><p style='margin-bottom:12.0pt;background:white;background-position:initial initial;background-repeat:initial initial'><span style='font-size:10.5pt;font-family:"Arial","sans-serif"'>Hi</span><o:p></o:p></p><p style='margin-bottom:12.0pt;background:white;background-position:initial initial;background-repeat:initial initial'><span style='font-size:10.5pt;font-family:"Arial","sans-serif"'>Currently LLVM ARM backend is still using the x86 way to generate position independent code. The algorithm retrieves the pointer of global offset table at first. However, GCC has been using the label relative offset to computer position independent code. The GCC way results smaller code size in ARM architecture. This patch is to implement GCC way to generate position independent code.</span><o:p></o:p></p><p style='margin-bottom:12.0pt;background:white;background-position:initial initial;background-repeat:initial initial'><span style='font-size:10.5pt;font-family:"Arial","sans-serif"'>In the attachment.<br>pic.diff is the code patch<br>the rest of four files are the test validation results before and after code changed</span><o:p></o:p></p><div><div><p class=MsoNormal><span style='font-size:11.0pt;font-family:"Calibri","sans-serif"'>Please give a review</span><o:p></o:p></p></div></div><div><div><p class=MsoNormal><span style='font-size:11.0pt;font-family:"Calibri","sans-serif"'> </span><o:p></o:p></p></div></div><div><div><p class=MsoNormal><span style='font-size:11.0pt;font-family:"Calibri","sans-serif"'>Thanks,</span><o:p></o:p></p></div></div><div><div><p class=MsoNormal><span style='font-size:11.0pt;font-family:"Calibri","sans-serif"'> </span><o:p></o:p></p></div></div><div><div><p class=MsoNormal><span style='font-size:11.0pt;font-family:"Calibri","sans-serif"'> Yin</span><o:p></o:p></p></div></div><div><p class=MsoNormal><span style='font-size:13.5pt;font-family:"Helvetica","sans-serif"'><report.simple.new.txt><report.simple.org.txt><cross.new><<a href="http://cross.org"><span style='color:purple'>cross.org</span></a>><pic.diff>_______________________________________________<br>llvm-commits mailing list<br><a href="mailto:llvm-commits@cs.uiuc.edu"><span style='color:purple'>llvm-commits@cs.uiuc.edu</span></a><br><a href="http://lists.cs.uiuc.edu/mailman/listinfo/llvm-commits"><span style='color:purple'>http://lists.cs.uiuc.edu/mailman/listinfo/llvm-commits</span></a></span><o:p></o:p></p></div></div></div><div><p class=MsoNormal> <o:p></o:p></p></div></div><p class=MsoNormal><span style='font-size:13.5pt;font-family:"Helvetica","sans-serif"'><pic.pdf><o:p></o:p></span></p></div></div><p class=MsoNormal><o:p> </o:p></p></div></div></body></html>