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</o:shapelayout></xml><![endif]--></head><body lang=EN-US link=blue vlink=purple><div class=WordSection1><p class=MsoNormal>Hey,<o:p></o:p></p><p class=MsoNormal><o:p> </o:p></p><p class=MsoNormal>I attached the patch to allow multiple reductions in one statement. The dependency analysis changes over the last days allow us to handle them now without further changes.<o:p></o:p></p><p class=MsoNormal><o:p> </o:p></p><p class=MsoNormal>We discussed already the basic idea but to summarize it:<o:p></o:p></p><p class=MsoNormal> Look at each load-store pair in the statement and check if they are connected by a binary operator which is commutative & associative.<o:p></o:p></p><p class=MsoNormal> If the load-store chain looks good we also verify that no other access in this statement might “interfere”, thus it might access the same<o:p></o:p></p><p class=MsoNormal> memory locations at some point. This check overestimates the actual problem but it is an easy way to guarantee no intermediate value<o:p></o:p></p><p class=MsoNormal> will escape or be overwritten during the execution. The overestimation prevents us at the moment to consider statements like<o:p></o:p></p><p class=MsoNormal> A[i] += A[j] which is a reduction for certain values of I and j but not all.<o:p></o:p></p><p class=MsoNormal><o:p> </o:p></p><p class=MsoNormal>I also attached a couple of test cases as we now are able to detect a lot of different reductions.<o:p></o:p></p><p class=MsoNormal><o:p> </o:p></p><p class=MsoNormal>I’d like some feedback on this one.<o:p></o:p></p><p class=MsoNormal><o:p> </o:p></p><p class=MsoNormal>Best regards,<o:p></o:p></p><p class=MsoNormal> Johannes<o:p></o:p></p><p class=MsoNormal><o:p> </o:p></p><p class=MsoNormal>--<o:p></o:p></p><p class=MsoNormal><o:p> </o:p></p><p class=MsoNormal>Johannes Doerfert<o:p></o:p></p><p class=MsoNormal>Employee of Qualcomm Innovation Center, Inc.<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>