Security-improving technologies which could be deployed now
Posted Oct 16, 2004 0:22 UTC (Sat) by garloff
In reply to: Security-improving technologies which could be deployed now
Parent article: Security-improving technologies which could be deployed now
> As for the 1% overhead for PIE executable on x86, for programs making
> heavy use of global symbols in critical path, the overhead is closer
> to 5% and I have examples (using hand-made assembly) where it reach
Indeed, on x86, where you already have a shortage of general purpose
registers, PIC will waste one more integer register.
Unfortunately, this happens on compute intensive tasks where you really
care. Think bzip2, gcc, ...
5% is the number seen by me as well.
On x86-64, you have twice as many GPRs and you normally don't even need
to offer one for PIC, due to the nice RIP relative addressing mode.
Thus the low overhead. The gcc/toolchain developers have done a nice
job of making sure that PIC code runs nicely on x86-64!
to post comments)