On Sun, Jun 16, 2019 at 11:59 PM Alexei Starovoitov <alexei.starovoitov@xxxxxxxxx> wrote: > > On Thu, Jun 6, 2019 at 6:31 PM Andreas Steinmetz <ast@xxxxxxxx> wrote: > > > > Below is the source in question. It may look a bit strange but I > > had to extract it from the project and preset parameters to fixed > > values. > > It takes from 2.8 to 4.5 seconds to load, depending on the processor. > > Just compile and run the code below. > > Thanks for the report. > It's interesting one indeed. > 600+ instructions consume > processed 280464 insns (limit 1000000) max_states_per_insn 15 > total_states 87341 peak_states 580 mark_read 45 > > The verifier finds a lot of different ways to go through branches > in the program and majority of the states are not equivalent and > do not help pruning, so it's doing full brute force walk of all possible > combinations. > We need to figure out whether there is a way to make it smarter. btw my pending backtracking logic helps it quite a bit: processed 164110 insns (limit 1000000) max_states_per_insn 11 total_states 13398 peak_states 349 mark_read 10 and it's 2x faster to verify, but 164k insns processed shows that there is still room for improvement.
