bugpoint reads the specified list of .bc or .ll files specified on the command-line and links them together. It then runs the specified LLVM passes on the resultant bytecode file. If any of the passes crash, or if they produce an LLVM module which is not verifiable, bugpoint enters "crash debugging mode". Otherwise, bugpoint tries to run the resultant program with a code generator. If the code generated program does not match the reference output, it enters "miscompilation debugging mode". If the -mode option is specified, bugpoint enters "code generator debugging mode".
opt -load <plugin.so> -help