Ah, yea, that would be an interesting experiment. I'd expect more savings in code size and fewer savings in CPU time. And unless the savings are really big I'd probably not want the change in trunk (we can't make it the only mode; having too modes is too much extra complexity)
--kcc On Tue, Apr 1, 2014 at 5:10 AM, Yuri Gribov <[email protected]> wrote: > > More details? > > Ok. So currently we initialize shadow memory via anonymous mmap which > effectively fills it with zeros. If we filled it with eights instead > (by mmapping /dev/byte8), we could simplify Asan check to a single > comparison: > > byte *shadow_address = MemToShadow(address); > byte shadow_value = *shadow_address; > byte last_accessed_byte = (address & 7) + kAccessSize - 1; > if (last_accessed_byte >= shadow_value) { > ReportError(address, kAccessSize, kIsWrite); > } > > -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.
