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simdjson
Parsing gigabytes of JSON per second : used by Facebook/Meta Velox, the Node.js runtime, ClickHouse, WatermelonDB, Apache Doris, Milvus, StarRocks
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InfluxDB
Power Real-Time Data Analytics at Scale. Get real-time insights from all types of time series data with InfluxDB. Ingest, query, and analyze billions of data points in real-time with unbounded cardinality.
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PMOVMSKB is a great instruction, and 3c understates how cheap it is - if you have a throughput problem (rather than a latency problem) it's even more efficient relative to the ARM equivalent.
I have a blog post about coping strategies for working around the absence of PMOVMSKB on NEON:
https://branchfree.org/2019/04/01/fitting-my-head-through-th...
We used these techniques in simdjson (which I presume still uses them; the code has changed considerably since I built this): https://github.com/simdjson/simdjson
The best techniques for mitigating the absence of PMOVMSKB require that you use LD4, which results in interleaved inputs. This can sometimes make things easier, sometimes harder for your underlying lexing algorithm - sadly, it's not a 1:1 transformation of the original x86 code.
> I'm somewhat curmudgeonly w.r.t. SVE, insisting that while the sole system in existence is a HPC machine from Fujitsu, that for practical purposes it doesn't really exist and isn't worth learning. I will likely revise this opinion when ARM vendors decide to ship something (likely soon, by most roadmaps).
Fair enough. I have high hopes for SVE, though. The first-faulting memory ops and predicate bisection features look like a vectorization godsend.
> There's only so much space in my brain.
I'm still going to attempt a nerd-sniping with the published architecture manual. Fujitsu includes a detailed pipeline description including instruction latencies. Granted its just one part, and its an HPC-focused part at that. But its not every day that this level of detail gets published in the ARM world.
https://github.com/fujitsu/A64FX/tree/master/doc
> I was irate to discover that you can't do logic ops on 8b/16b lanes with masking; as usual the 32b/64b mafia strike again.
SVE is blessedly uniform in this regard.
> It would be nice if the explicit mask operations were cheaper. Unfortunately, they crowd out SIMD operations.
This goes both ways, though. A64FX has two vector execution pipelines and one dedicated predicate execution pipeline. Since the vector pipelines cannot execute predicate ops, I expect it is not difficult to construct cases where code gets starved for predicate execution resources.