[AArch64] error in backend: Do not know how to split the result of this operator

[vfdff]

• There's a compilation problem with sve, https://godbolt.org/z/MYKzeKx3Y

  it reports fatal error: error in backend: Do not know how to split the result of this operator!

• related code

  llvm-project/llvm/lib/CodeGen/SelectionDAG/LegalizeVectorTypes.cpp

  Line 673 in 0d17e1f

  report_fatal_error("Do not know how to scalarize this operator's "

[llvmbot]

@llvm/issue-subscribers-backend-aarch64

Author: Allen (vfdff)

* There's a compilation problem with **sve**, https://godbolt.org/z/MYKzeKx3Y > it reports **fatal error: error in backend: Do not know how to split the result of this operator!**

• related code

  llvm-project/llvm/lib/CodeGen/SelectionDAG/LegalizeVectorTypes.cpp

  Line 673 in 0d17e1f

  report_fatal_error("Do not know how to scalarize this operator's "

[vfdff]

Add option -mllvm -lower-interleaved-accesses=false can avoid this problem.
In the pass, @llvm.experimental.vector.deinterleave2.nxv8f64 transforms into @llvm.aarch64.sve.ld2.sret.nxv4f64, then @llvm.aarch64.sve.ld2.sret.nxv4f64 failed in ISel

[vfdff]

• More simple case: https://gcc.godbolt.org/z/x94TdE6hG

declare { <vscale x 4 x double>, <vscale x 4 x double> } @llvm.aarch64.sve.ld2.sret.nxv4f64(<vscale x 4 x i1>, ptr)

define { <vscale x 4 x double>, <vscale x 4 x double> } @deinterleave_nxptr_factor2(ptr nocapture readonly %ptr) local_unnamed_addr #0 {
  %ldN = call { <vscale x 4 x double>, <vscale x 4 x double> } @llvm.aarch64.sve.ld2.sret.nxv4f64(<vscale x 4 x i1> shufflevector (<vscale x 4 x i1> insertelement (<vscale x 4 x i1> poison, i1 true, i64 0), <vscale x 4 x i1> poison, <vscale x 4 x i32> zeroinitializer), ptr %ptr)
  ret { <vscale x 4 x double>, <vscale x 4 x double> } %ldN
}