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</o:shapelayout></xml><![endif]--></head><body lang=EN-US link="#0563C1" vlink="#954F72"><div class=WordSection1><p class=MsoNormal>Hello,<o:p></o:p></p><p class=MsoNormal><o:p> </o:p></p><p class=MsoNormal>We are now facing a bug caused by the GVN pass, only part of the code was optimized. I have found that the problem is cause by an Limit in lib/Analysis/MemoryDependenceAnalysis.cpp<o:p></o:p></p><p class=MsoNormal><o:p> </o:p></p><p class=MsoNormal>00055 static cl::opt<unsigned> BlockScanLimit(<o:p></o:p></p><p class=MsoNormal>00056 "memdep-block-scan-limit", cl::Hidden, cl::init(100),<o:p></o:p></p><p class=MsoNormal>00057 cl::desc("The number of instructions to scan in a block in memory "<o:p></o:p></p><p class=MsoNormal>00058 "dependency analysis (default = 100)"));<o:p></o:p></p><p class=MsoNormal>The args can be changed using opt, but we are using libclang and libllvm and running pass with llvm passmangers. I know that –mllvm can pass llvm args, but the llvm::cl::ParseCommandLineOptions has some issues with mutlethread and I have reported a bug in <a href="https://llvm.org/bugs/show_bug.cgi?id=25735">https://llvm.org/bugs/show_bug.cgi?id=25735</a>, and we could not use this for now.<o:p></o:p></p><p class=MsoNormal><o:p> </o:p></p><p class=MsoNormal>So if there is another way to pass this memdep-block-scan-limit into the pass manager or context? Or how could I set this memdep-block-scan-limit right with libclang and libllvm?<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>Xiuli<o:p></o:p></p></div></body></html>