Vector-length agnostic
Beginner
A way of writing vector programs so the same program works on chips whose row-of-numbers units are different widths.
Novice
A style of vector instruction set (Arm SVE, RISC-V V) where the program doesn’t fix the vector width. It asks the hardware how many elements fit and loops accordingly, so one compiled program runs on narrow and wide hardware alike.
Expert
VL is a run-time value: SVE derives loop control from predicates (whilelt) and increments by the element count (incd); RVV’s vsetvli returns vl from the requested length. No remainder loop, but data layouts and register spills can’t assume a compile-time size.
Explained in Multicore and vector units (Architectures).
See also: Vector (SIMD) extension, SIMD (single instruction, multiple data).