[PATCH] D116362: [TTI] Support ScalableVectorType in getShuffleCost with SK_Broadcast kind

[Roger Ferrer Ibanez via Phabricator via llvm-commits]

rogfer01 added inline comments.


================
Comment at: llvm/test/Analysis/CostModel/RISCV/rvv-shuffle.ll:14
+; CHECK-NEXT:  Cost Model: Invalid cost for instruction: %5 = shufflevector <vscale x 4 x i32> undef, <vscale x 4 x i32> undef, <vscale x 4 x i32> zeroinitializer
+; CHECK-NEXT:  Cost Model: Found an estimated cost of 0 for instruction: %6 = shufflevector <vscale x 1 x i64> undef, <vscale x 1 x i64> undef, <vscale x 1 x i32> zeroinitializer
+; CHECK-NEXT:  Cost Model: Invalid cost for instruction: %7 = shufflevector <vscale x 2 x i64> undef, <vscale x 2 x i64> undef, <vscale x 2 x i32> zeroinitializer
----------------
I'm curious, why does this one have cost zero and all others are invalid?

Maybe we're getting the min element count somewhere and assuming this is a scalar boxed in a fixed vector of length 1?


Repository:
  rG LLVM Github Monorepo

CHANGES SINCE LAST ACTION
  https://reviews.llvm.org/D116362/new/

https://reviews.llvm.org/D116362