>>> Do you have any evidence that this adversely affects debugger >>> performance? >> >> For our internal tool chains, we now have to perform a string search to >> find the definition. In theory, the extra search should make it slower. > > > It'd be really nice to quantify this. > >> >> Yes, the accelerator table can help the search. >>
The accelerator table should help - since it only has definitions and it's on by default for darwin. What's up that's causing a performance degradation? -eric >>> >>> >>>> >>>> Is it reasonable for this commit to be enabled only for >>>> limit-debug-info, when no-limit-debug-info is on, we don't see effects of >>>> this patch? >>> >>> >>> GCC does this by default, at least on Linux - I haven't tested on MacOS. >>> I would guess it does so there too (but as you point out, there are >>> different tradeoffs there, so I might be wrong). >>> >>> I'd like to understand the performance tradeoff to justify such a large >>> regression in debug info size (it's worth about ~20% on Clang/LLVM based on >>> my experiments). >> >> >> Our default is -limit-debug-info, so this will be on by default. I was >> asking whether we should guard this so when people use >> "-fno-limit-debug-info", they will get the definition. > > > -flimit-debug-info has some relatively rough heuristics that aren't as high > confidence as the vtable based debug info emission mechanism, I'm not sure > we want to group these together. (eg: it seems likely that a user might have > issues with the minimization caused by -flimit-debug-info and want to turn > it off, if in doing so they also turn off the vtable based, > higher-confidence optimization, that would be unfortunate) > > - David > >> >> >> Thanks, >> Manman >> >>> >>> >>> >>> - David >>> >>>> >>>> >>>> Thanks, >>>> Manman >>>> > > > _______________________________________________ > cfe-commits mailing list > [email protected] > http://lists.cs.uiuc.edu/mailman/listinfo/cfe-commits > _______________________________________________ cfe-commits mailing list [email protected] http://lists.cs.uiuc.edu/mailman/listinfo/cfe-commits
