simde icon indicating copy to clipboard operation
simde copied to clipboard

Published 20 hours ago • verified publisher icon simd-everywhere

re-implement some of the FCVTZS/FCVTMS/FCVTPS/FCVTNS

Open mr-c opened this issue 3 months ago • 1 comments

Recent Qemu confirms the different behavior that was seen on mac M1 and a Pixel 4a 5g phone versus our previous implementation.

To fix this:

  1. Revert https://github.com/simd-everywhere/simde/commit/339ffe4ca89bf6698cab0c8420fe813a4e293aec
  2. Adjust the test vectors to match the hardware behavior (or that of a recent Qemu version)
  3. Adjust the software implementations of those intrinsics to match the new test vectors

Note that Arm defines Round towards Zero (RZ) mode as

Means that results are rounded to the nearest representable number that is no greater in magnitude than the unrounded result.

mr-c avatar Mar 20 '24 14:03 mr-c