[all-commits] [llvm/llvm-project] 877d1b: [SelectionDAG][VP] Add splitting/widening for VP_L...

[Fraser Cormack via All-commits]

  Branch: refs/heads/main
  Home:   https://github.com/llvm/llvm-project
  Commit: 877d1b3d0770d7ce26791224088025993f89721c
      https://github.com/llvm/llvm-project/commit/877d1b3d0770d7ce26791224088025993f89721c
  Author: Fraser Cormack <fraser at codeplay.com>
  Date:   2022-01-15 (Sat, 15 Jan 2022)

  Changed paths:
    M llvm/include/llvm/CodeGen/SelectionDAG.h
    M llvm/lib/CodeGen/SelectionDAG/LegalizeTypes.h
    M llvm/lib/CodeGen/SelectionDAG/LegalizeVectorTypes.cpp
    M llvm/lib/CodeGen/SelectionDAG/SelectionDAG.cpp
    M llvm/lib/CodeGen/SelectionDAG/SelectionDAGBuilder.cpp
    M llvm/lib/Target/RISCV/RISCVISelLowering.cpp
    M llvm/test/CodeGen/RISCV/rvv/fixed-vectors-vpload.ll
    M llvm/test/CodeGen/RISCV/rvv/fixed-vectors-vpstore.ll
    M llvm/test/CodeGen/RISCV/rvv/vpload.ll
    M llvm/test/CodeGen/RISCV/rvv/vpstore.ll

  Log Message:
  -----------
  [SelectionDAG][VP] Add splitting/widening for VP_LOAD and VP_STORE

Original patch by @hussainjk.

This patch was split off from D109377 to keep vector legalization
(widening/splitting) separate from vector element legalization
(promoting).

While the original patch added a third overload of
SelectionDAG::getVPStore, this patch takes the liberty of collapsing
those all down to 1, as three overloads seems excessive for a
little-used node.

The original patch also used ModifyToType in places, but that method
still crashes on scalable vector types. Seeing as the other VP
legalization methods only work when all operands need identical
widening, this patch follows in that vein.

Reviewed By: craig.topper

Differential Revision: https://reviews.llvm.org/D117235