By: Jan Wassenberg (jan.wassenberg.delete@this.gmail.com), May 20, 2022 10:00 pm
Room: Moderated Discussions
-.- (blarg.delete@this.mailinator.com) on May 20, 2022 4:04 am wrote:
> Well compressstore is actually two instructions disguised as one. If you don't care
> about writing extra zeroes at the end, the CNT+WHILELT isn't necessary either.
Fair point. I mention it because our recent Quicksort relies heavily on this instruction and in most cases does require the masking.
> But the point here is that WHILELT is supposed to be fairly important to a lot
> of SVE code, and helps with reducing unforeseen costs with auto-vectorization.
Makes sense that it's important for autovectorization. For manual vectorization, if we control the data layout, we can often just pad and avoid the need for WHILELT.
> Well compressstore is actually two instructions disguised as one. If you don't care
> about writing extra zeroes at the end, the CNT+WHILELT isn't necessary either.
Fair point. I mention it because our recent Quicksort relies heavily on this instruction and in most cases does require the masking.
> But the point here is that WHILELT is supposed to be fairly important to a lot
> of SVE code, and helps with reducing unforeseen costs with auto-vectorization.
Makes sense that it's important for autovectorization. For manual vectorization, if we control the data layout, we can often just pad and avoid the need for WHILELT.
