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Dear Momchil,</div>
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Thanks a lot for your detailed information and yes, it seems that loop strength reduction is limited by scaled index addressing mode. Now, I implement a simple LSR pass to do LSR aggressively, ignoring the scaled addressing mode.</div>
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Thanks again for you time and suggestions!<br>
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<div><font size="2" face="Calibri,sans-serif"><span style="font-size:12pt">Best regards,</span></font><span style="font-size:12pt">
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<div style="margin:0"><font size="2" face="Calibri,sans-serif"><span style="font-size:12pt">Tingyuan LIANG</span></font></div>
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<div style="margin:0"><font size="2" face="Calibri,sans-serif"><span style="font-size:12pt">MPhil Student</span></font></div>
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<div style="margin:0"><font size="2" face="Calibri,sans-serif"><span style="font-size:12pt">Department of Electronic and Computer Engineering</span></font></div>
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<div style="margin:0"><font size="2" face="Calibri,sans-serif"><span style="font-size:12pt">The Hong Kong University of Science and Technology</span></font></div>
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<div id="divRplyFwdMsg" dir="ltr"><font face="Calibri, sans-serif" style="font-size:11pt" color="#000000"><b>From:</b> Momchil Velikov <momchil.velikov@gmail.com><br>
<b>Sent:</b> Tuesday, April 16, 2019 2:40 AM<br>
<b>To:</b> Tingyuan LIANG<br>
<b>Cc:</b> llvm-dev@lists.llvm.org<br>
<b>Subject:</b> Re: [llvm-dev] Loop Strength Reduction Pass Does Not Work for Some Varialbles Related to Induction Variables</font>
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Some multiplications, used in address calculation, may stay after loop strength reduction, if the target machine has scaled index addressing mode.<br>
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--<br>
Momchil Velikov,<br>
Senior Compiler Engineer<br>
Arm
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