3 ms·
You can't do 2048 bits of addition in one SVE instruction; not portably, at least (and definitely not on any existing hardware). While the maximum SVE register
by dzaima 2y ago
You can't do 2048 bits of addition in one SVE instruction; not portably, at least (and definitely not on any existing hardware). While the maximum SVE register size is 2048 bits, the minimum is 128 bits, and the hardware chooses the supported register size, not the programmer. For portable SVE, your code needs to work for all of those widths, not just the smallest or largest. (of related note is RISC-V RVV, which allows you to group up to 8 registers together, allowing a minimum portable operation width of 128×8 = 1024 bits in a single instruction (and up to 65536×8 = 64KB for hypothetical crazy hardware with max VLEN), but SVE/SVE2 don't have any equivalent)