3 ms·
If you think of posits as a storage format, it's true that you only need an extra posit->float decoder, but you need bfloat16 to exactly decode all 8-bit posits
by pclmulqdq 3y ago
If you think of posits as a storage format, it's true that you only need an extra posit->float decoder, but you need bfloat16 to exactly decode all 8-bit posits into a single, common FP format.
In terms of hardware to operate directly on posits, things get ugly. Floats are actually relatively easy to work with due to the normalized storage format and fixed precision across the range of numbers, while posits don't have that.
- Dylan16807 3y ago> If you think of posits as a storage format, it's true that you only need an extra posit->float decoder, but you need bfloat16 to exactly decode all 8-bit posits into a single, common FP format. But you're not limited to powers of two. If you're decoding to 16 bit floats then you can use posits up to 13 bits wide. > In terms of hardware to operate directly on posits, things get ugly. Floats are actually relatively easy to work with due to the normalized storage format and fixed precision across the range of numbers, while posits don't have that. But is that extra shifting bigger than the multiplier unit? It's hard for me to see it growing the circuit that much.