From: Alexey Dobriyan > Sent: 07 May 2018 22:38 > > Use INT3 instead of NOP. All that padding between functions is > an illegal area, no legitimate code should jump into it. > > I've checked x86_64 allyesconfig disassembly, all changes looks sane: > INT3 is only used after RET or unconditional JMP.
I thought there was a performance penalty (on at least some cpu) depending on the number of and the actual instructions used for padding. I believe that is why gcc generates a small number of very long 'nop' instructions when padding code. David