On Fri, Mar 28, 2014 at 9:44 AM, Yuri Gribov <[email protected]> wrote:
> All, > > I was wondering whether there are plans to add (optional) out-of-line > instrumentation of memory accesses i.e. use function calls like > __asan_read1 instead of explicit instruction sequence to access shadow > memory? We don't have any such plans, but patches are welcome. You will need a change in the run-time library and in both compilers. :( > AFAIK KernelSanitizer is already using this approach. > You mean, kasan (Kernel-AddressSanitizer)? kasan is just a prototype, it's easier to play with the prototype this way. Eventually it will have inlined checks. > Memory savings would be quite significant which is important for > mobile applications. You mean code size? (of course, it translates into memory usage) > I also wouldn't expect performance to drop that > much (branch prediction, etc.). Actually it may even increase (just > take a look at the horrible instrumentation code that is generated on > ARM). > I think that outlining the checks will cause dramatic slowdown (instead of one load, you access memory 3 times: call, shadow load, ret). But we never know before we try and benchmark. The numbers on ARM may indeed be different than on x86. --kcc > > -Y > > -- > You received this message because you are subscribed to the Google Groups > "address-sanitizer" group. > To unsubscribe from this group and stop receiving emails from it, send an > email to [email protected]. > For more options, visit https://groups.google.com/d/optout. > -- You received this message because you are subscribed to the Google Groups "address-sanitizer" group. To unsubscribe from this group and stop receiving emails from it, send an email to [email protected]. For more options, visit https://groups.google.com/d/optout.
