Review comment: vec_round semantics are wrong #81

Open
opened 1 year ago by Bill Schmidt · 0 comments

We need to properly document that the semantics for ties are different for vector float and vector double arguments. For vector float, the semantics are round-to-nearest, ties-to-even. For vector double, the semantics are round-to-nearest, ties-away-from-zero. The reasons these semantics differ are somewhat lost in the mists of time, but they need to be documented.

Changing the semantics so they are consistent would be possible, but might break working code in the field, and is likely to perform poorly on several processor implementations. So the compiler leadership team has determined to simply make sure the documentation is correct.

We need to properly document that the semantics for ties are different for vector float and vector double arguments. For vector float, the semantics are round-to-nearest, ties-to-even. For vector double, the semantics are round-to-nearest, ties-away-from-zero. The reasons these semantics differ are somewhat lost in the mists of time, but they need to be documented. Changing the semantics so they are consistent would be possible, but might break working code in the field, and is likely to perform poorly on several processor implementations. So the compiler leadership team has determined to simply make sure the documentation is correct.
Sign in to join this conversation.
No Milestone
No project
No Assignees
1 Participants
Notifications
Due Date

No due date set.

Dependencies

This issue currently doesn't have any dependencies.

Loading…
There is no content yet.