"Scalable" Vectors, because it is the `setvl` instruction that
presents the **programmer** with explicit control over Vector length.
-ARM NEON, AVX-512 and ARM SVE2 are all Predicated SIMD ISAs and
-**do not provide Scalability to the Programmer**. SVE2 is **Silicon**
+VSX and NEON are PackedSIMD, and
+AVX-512 and ARM SVE2 are Predicated SIMD ISAs.
+**None of them provide Scalability to the Programmer**. SVE2 is **Silicon**
Scalable, not **Programmer** Scalable: the distinction is profoundly
-important.
+important (already causing problems).
For Predicated SIMD, Programmers must emulate Cray-style scaling
through explicit predicate masking, which increases instruction count in
hot-loops.