Apparently IEEE-754 guarantees bit-identical (≤½ ulp error) results for +, -, ×, ÷, and √ — but only those? Do processors usually comply?
-
thank you very much! Even on GPUs? How about √?
Can't vouch for hardware-supported √. GPUs - AFAIK can be made to work on new ones, can be tough: https://developer.nvidia.com/sites/default/files/akamai/cuda/files/NVIDIA-CUDA-Floating-Point.pdf …
-
-
oh man. apparently due to the introduction of FMA, even a*a+b can now produce non-bit-identical results "correctly".
-
reasonable compilers let you disable FMAs. If I got it right, NVIDIA's won't, gives you intrinsics for non-fused MACs. Painful!
- 5 more replies
New conversation -
-
-
Oh, this is awesome. Thanks!
Thanks. Twitter will use this to make your timeline better. UndoUndo
-
Loading seems to be taking a while.
Twitter may be over capacity or experiencing a momentary hiccup. Try again or visit Twitter Status for more information.