Luke Lau a761e26b23
[RISCV] Allow non-loop invariant steps in RISCVGatherScatterLowering (#122244)
The motivation for this is to allow us to match strided accesses that
are emitted from the loop vectorizer with EVL tail folding (see #122232)

In these loops the step isn't loop invariant and is based off of
@llvm.experimental.get.vector.length.

We can relax this as long as we make sure to construct the updates after
the definition inside the loop, instead of the preheader.

I presume the restriction was previously added so that the step would
dominate the insertion point in the preheader. I can't think of why it
wouldn't be safe to calculate it in the loop otherwise.
2025-01-17 08:58:56 +08:00
..
2023-10-18 15:01:17 +08:00