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</o:shapelayout></xml><![endif]--></head><body lang=ZH-CN link=blue vlink=purple style='text-justify-trim:punctuation'><div class=WordSection1><p class=MsoNormal><span lang=EN-US>Hi,<o:p></o:p></span></p><p class=MsoNormal><span lang=EN-US><o:p> </o:p></span></p><p class=MsoNormal align=left style='text-align:left'><span lang=EN-US>Please consider a patch in the attachment as fix for PR14824: Optimization arm_ldst_opt inserts newly generated instruction vldmia at incorrect. http://llvm.org/bugs/show_bug.cgi?id=14824<o:p></o:p></span></p><p class=MsoNormal align=left style='text-align:left'><span lang=EN-US><o:p> </o:p></span></p><p class=MsoNormal align=left style='text-align:left'><span lang=EN-US>The problem is that there is overlap for lack of WAW (write after write) dependence check in ARMLoadStoreOpt::LoadStoreMultipleOpti. So we check the dependence before inserting an instruction into optimizing queue. If the dependence does exist, we will optimize all the instructions already in the queue.<o:p></o:p></span></p><p class=MsoNormal align=left style='text-align:left'><span lang=EN-US><o:p> </o:p></span></p><p class=MsoNormal align=left style='text-align:left'><span lang=EN-US>The attached patch fixes that problem. BTW, to write a simple test case is hard, as the overlapped instructions are removed as dead instructions in usual. So the regression test attached is the original test case by Jiangning who found this bug. There is no unexpected failure of the regression test. The test-suite hasn’t been tested for the lack of equipment.<o:p></o:p></span></p><p class=MsoNormal align=left style='text-align:left'><span lang=EN-US><o:p> </o:p></span></p><p class=MsoNormal align=left style='text-align:left'><span lang=EN-US>Thanks,<o:p></o:p></span></p><p class=MsoNormal align=left style='text-align:left'><span lang=EN-US>-Hao<o:p></o:p></span></p></div></body></html>