3 ms·
That seems like a good idea against speculation based attacks too; predict within what is at hand, do not cause side effects.
by mjevans 2y ago
That seems like a good idea against speculation based attacks too; predict within what is at hand, do not cause side effects.
- phire 2y agoI didn't even notice that advantage. I was just thinking about how it minimised each branch target entry to about 16 bits. I suspect Apple are also using it as a way predictor. If the BTB points directly to the correct cacheline and each cacheline points to the next way then the only time you need to do a search is on a branch misspredit.