[Mlir-commits] [mlir] [mlir][vector] Replace unused shuffle operands / results with poison (PR #190763)

[Kelvin Li]

kkwli wrote:

This causes LIT failures in https://lab.llvm.org/buildbot/#/builders/157/builds/45765.

Reproducer:
```fortran
subroutine vec_cvf_test_r4r8(arg1)
  vector(real(8)), intent(in) :: arg1
  vector(real(4)) :: r
  r = vec_cvf(arg1)
end
```

Compile:
`flang -target powerpc64le-unknown-linux-gnu d.f90`

Output:
```
loc(".../d.f90":4:3): error: failed to legalize operation 'ub.poison': %0 = "ub.poison"() <{value = #ub.poison}> : () -> vector<16xi8>
error: Lowering to LLVM IR failed
loc(".../d.f90":1:1): error: cannot be converted to LLVM IR: missing `LLVMTranslationDialectInterface` registration for dialect for op: func.func
error: failed to create the LLVM module
```

https://github.com/llvm/llvm-project/pull/190763