ARM SVE vs AVX-512: Scalable Vectors vs Fixed 512-Bit SIMD
Arm SVE and x86 AVX-512 both provide predicated vector execution, but their software contracts differ fundamentally: scalable vector length versus a fixed 512-bit maximum width.
[ Research ]
Vector architecture
Vector registers, vector length, masking, predication, gather and scatter, chaining and scalable execution.
Gather and scatter instructions
Indexed vector memory access, its cost, and when a data layout change beats it.
What is vector-length agnostic programming?
Writing one kernel that uses whatever vector width the hardware provides.
What is vector length?
Vector length, element width and the difference between what a register holds and what an instruction processes.
What is a vector processor?
One instruction, many elements: vector registers, vector length and why describing parallelism beats discovering it.
RISC-V Vector vs ARM SVE: Two Scalable Vector Models
RISC-V Vector and Arm SVE both support vector-length-agnostic software, but they expose that capability differently through vl/configuration versus predicates and scalable vector types.
What Is Vector-Length Agnostic Programming?
Vector-length agnostic code avoids assuming one hardware vector width. Instead it progresses according to the active elements available on the current implementation.
What Is Vector Length?
Vector length can mean register capacity, active elements or a software vectorization factor. Distinguishing those meanings is essential when comparing AVX, SVE and RISC-V Vector.