[all-commits] [llvm/llvm-project] 1e7c1d: [SDAG] avoid crash from mismatched types in scalar...

[Sanjay Patel via All-commits]

  Branch: refs/heads/main
  Home:   https://github.com/llvm/llvm-project
  Commit: 1e7c1dd67cd63a6b14d5d4bd8e0e195e9a910f7b
      https://github.com/llvm/llvm-project/commit/1e7c1dd67cd63a6b14d5d4bd8e0e195e9a910f7b
  Author: Sanjay Patel <spatel at rotateright.com>
  Date:   2022-10-28 (Fri, 28 Oct 2022)

  Changed paths:
    M llvm/lib/CodeGen/SelectionDAG/DAGCombiner.cpp
    M llvm/test/CodeGen/X86/vec_shift5.ll

  Log Message:
  -----------
  [SDAG] avoid crash from mismatched types in scalar-to-vector fold

This bug was introduced with D136713 / 54eeadcf442df91aed0 .

As an enhancement, we could cast operands to the expected type,
but we need to make sure that is done correctly (zext vs. sext).
It's also possible (but seems unlikely) that an operand can have
a type larger than the result type.

Fixes #58661