Aren't they loosely modeled on riscV? RiscV has an arbitrary length vector extension. So did cray. They seem like a good idea. In practice, I usually structure

Aren't they loosely modeled on riscV? RiscV has an arbitrary length vector extension. So did cray. They seem like a good idea. In practice, I usually structure intermediate data products in memory with the largest simd size I expect the vectorizer will ever optimize for, so compiling it for something longer won't get me anything.