On Thu, Mar 27 2025 at 16:47, Neeraj Upadhyay wrote: > On 3/27/2025 3:57 PM, Thomas Gleixner wrote: >> The relevant registers are starting at regs[SAVIC_ALLOWED_IRR]. Due to >> the 16-byte alignment the vector number obviously cannot be used for >> linear bitmap addressing. >> >> But the resulting bit number can be trivially calculated with: >> >> bit = vector + 32 * (vector / 32); >> > > Somehow, this math is not working for me. I will think more on how this > works. From what I understand, bit number is: > > bit = vector % 32 + (vector / 32) * 16 * 8 > > So, for example, vector number 32, bit number need to be 128. > With you formula, it comes as 64. Duh. I did the math for 8 byte alignment. But for 16 byte it's obviously exactly the same formula just with a different multiplicator: bit = vector + 96 * (vector / 32); No?
