3 ms·
Agner Fog mentions that the CPU assumes different registers have different values and the calculation has to be rerun if it turns out a write with one register
by gliptic 6y ago
Agner Fog mentions that the CPU assumes different registers have different values and the calculation has to be rerun if it turns out a write with one register invalidated a cached read with another register.
That means you can measure this penalty and infer that the registers had the same or overlapping addresses.
- gpderetta 6y agoThis is no different than the existing memory aliasing predictor that has existed for a long time already though, so it doesn't add any new speculation opportunity as far as I can tell.