[PATCH] D110319: [SelectionDAG] Fixed the scalable vectors issue on WidenVecRes_OverflowOp&WidenVecRes_SELECT

[Fraser Cormack via Phabricator via llvm-commits]

frasercrmck added a comment.

I know they're both small changes but I think it would be good to split this patch up into separate parts: overflow and select. They're conceptually distinct changes. Then we could have more targeted tests for each operation and each change.

Also RISC-V would benefit from the `select` change, e.g., adding this sort of test to `test/CodeGen/RISCV/rvv/vselect-int-rv32.ll` and `vselect-int-rv64.ll`

  define <vscale x 3 x i8> @vmerge_vv_nxv3i8(<vscale x 3 x i8> %va, <vscale x 3 x i8> %vb, <vscale x 3 x i1> %cond) {
    %vc = select <vscale x 3 x i1> %cond, <vscale x 3 x i8> %va, <vscale x 3 x i8> %vb
    ret <vscale x 3 x i8> %vc
  }



================
Comment at: llvm/lib/CodeGen/SelectionDAG/LegalizeTypes.cpp:854
 void DAGTypeLegalizer::SetWidenedVector(SDValue Op, SDValue Result) {
-  assert(Result.getValueType() ==
-         TLI.getTypeToTransformTo(*DAG.getContext(), Op.getValueType()) &&
+  assert(Result.getValueType().getVectorElementType() ==
+             TLI.getTypeToTransformTo(*DAG.getContext(), Op.getValueType())
----------------
This looks suspicious to me. What's it for?


Repository:
  rG LLVM Github Monorepo

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  https://reviews.llvm.org/D110319/new/

https://reviews.llvm.org/D110319