Jesper Antonsson via llvm-dev
2016-Apr-21 14:32 UTC
[llvm-dev] opt function passes swallowed
Hi, I've observed that FunctionPasses are not run when a specific argument order is handed to opt. I.e. when I specify: opt -O3 -float2int file.ll ... the FunctionPasses specified by populateFunctionPasses() are not run. However, if I put the -O3 after all manually specified passes, then the FunctionPasses are run: opt -float2int -O3 file.ll In the code (opt.cpp), we are explicitly checking the argument order (somewhere around line 537 for me): if (OptLevelO3 && OptLevelO3.getPosition() < PassList.getPosition(i)) { AddOptimizationPasses(Passes, *FPasses, 3, 0); OptLevelO3 = false; } Note that we set OptLevelO3 to false above. Later, we run FPasses only if some OptLevelO<n> is true: if (OptLevelO1 || OptLevelO2 || OptLevelOs || OptLevelOz || OptLevelO3) { FPasses->doInitialization(); for (Function &F : *M) FPasses->run(F); FPasses->doFinalization(); } Thus FPasses are not run if -O<n> comes before any manually specified passes in the argument list. Anyone knows if this is intentional and if so, why? Regards, Jesper -------------- next part -------------- An HTML attachment was scrubbed... URL: <http://lists.llvm.org/pipermail/llvm-dev/attachments/20160421/87e53bc0/attachment.html>