[PATCH] D130895: [RISCV] Make VL choosing for a splat-like VMV based on its users

[Craig Topper via Phabricator via llvm-commits]

craig.topper added inline comments.


================
Comment at: llvm/lib/Target/RISCV/RISCVISelDAGToDAG.cpp:2500
+                              const RISCVInstrInfo &TII) {
+  if (!UI->isMachineOpcode())
+    return false;
----------------
VL shrinking would not be legal for vs2 of a `vrgather.vv` or `vrgatherei16.vv`. The indices can select elements above VL.

I think it's also not legal for vs2 of `vslidedown.vi` and `vslidedown.vx`.


Repository:
  rG LLVM Github Monorepo

CHANGES SINCE LAST ACTION
  https://reviews.llvm.org/D130895/new/

https://reviews.llvm.org/D130895