search for: 7cnlopes

...John Regehr; Juneyoung Lee Subject: Re: [llvm-dev] A bug related with undef value when bootstrap MemorySSA.cpp Hi Wei, [+CC the other undef folks] This is the same bug as https://na01.safelinks.protection.outlook.com/?url=https%3A%2F%2Fbugs.llvm.org%2Fshow_bug.cgi%3Fid%3D31652&data=02%7C01%7Cnlopes%40microsoft.com%7C971ae2063c8b420d2f1008d4cbec8f22%7C72f988bf86f141af91ab2d7cd011db47%7C1%7C0%7C636357664258073352&sdata=iCy8kUlWwJzQpXbXvOuhHpKyXBnntZPGvn%2FtxWsqun8%3D&reserved=0. The short answer here is that the loop unswitch transform and the GVN transform are justified via conflicting...

...def value when bootstrap > MemorySSA.cpp > > > > Hi Wei, > > > > [+CC the other undef folks] > > > > This is the same bug as https://na01.safelinks. > protection.outlook.com/?url=https%3A%2F%2Fbugs.llvm.org% > 2Fshow_bug.cgi%3Fid%3D31652&data=02%7C01%7Cnlopes%40microsoft.com% > 7C971ae2063c8b420d2f1008d4cbec8f22%7C72f988bf86f141af91ab2d7cd011 > db47%7C1%7C0%7C636357664258073352&sdata=iCy8kUlWwJzQpXbXvOuhHpKyXBnntZ > PGvn%2FtxWsqun8%3D&reserved=0. > > The short answer here is that the loop unswitch transform and the GVN > transf...

This is a bug found by internal compiler bootstrap, and possibly it is the root cause of https://bugs.llvm.org/show_bug.cgi?id=33652 and https://bugs.llvm.org/show_bug.cgi?id=33626. Here is the testcase 1.c. The original code is at MemorySSA.cpp:586 for rL307764. ------------------------- 1.c --------------------------- long a, c, d, e, f, m, cnt, i_hasval; volatile long b; void goo(long); void