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</o:shapelayout></xml><![endif]--></head><body lang=EN-US link=blue vlink=purple><div class=WordSection1><p class=MsoNormal>Hi,<o:p></o:p></p><p class=MsoNormal><o:p> </o:p></p><p class=MsoNormal> Generally, it is desirable to transform “(a + b) * c” to “a*c + b*c” for<o:p></o:p></p><p class=MsoNormal style='text-indent:9.0pt'>ARM with VMLx Forwarding, where a, b and c are vectors.<o:p></o:p></p><p class=MsoNormal style='text-indent:9.0pt'><o:p> </o:p></p><p class=MsoNormal> However, for (a + b)*(a + b), distribution will result in one extra<o:p></o:p></p><p class=MsoNormal> instruction.<o:p></o:p></p><p class=MsoNormal> With distribution:<o:p></o:p></p><p class=MsoNormal> x = a + b (vadd)<o:p></o:p></p><p class=MsoNormal> y = a * x (vmul)<o:p></o:p></p><p class=MsoNormal> z = y + b * y (vmla)<o:p></o:p></p><p class=MsoNormal> <o:p></o:p></p><p class=MsoNormal> Without distribution:<o:p></o:p></p><p class=MsoNormal> x = a + b (vadd)<o:p></o:p></p><p class=MsoNormal> z = x * x (vmul)<o:p></o:p></p><p class=MsoNormal> <o:p></o:p></p><p class=MsoNormal> This patch detects if a mul is a square of add/sub. If yes, skip<o:p></o:p></p><p class=MsoNormal> distribution.<o:p></o:p></p><p class=MsoNormal><o:p> </o:p></p><p class=MsoNormal>Please help to review the patch<o:p></o:p></p><p class=MsoNormal><o:p> </o:p></p><p class=MsoNormal>Thanks,<o:p></o:p></p><p class=MsoNormal>Weiming<o:p></o:p></p><p class=MsoNormal><o:p> </o:p></p><p class=MsoNormal>Qualcomm Innovation Center, Inc. is a member of Code Aurora Forum, hosted by The Linux Foundation<o:p></o:p></p><p class=MsoNormal><o:p> </o:p></p></div></body></html>