[GISel] unable to legalize instruction: %4:_(<2 x s16>) = G_INSERT_VECTOR_ELT

[vfdff]

test: https://gcc.godbolt.org/z/e3Wq9Mdar

define <2 x i16> @f(i16 %a, <2 x i16> %vec) {
  %vec1 = insertelement <2 x i16> %vec, i16 1, i32 0 
  ret <2 x i16> %vec1
}

• reproduce command: llc -mtriple=aarch64-eabi -global-isel=1 test_val1.ll -debug-only=instruction-select -stop-before=regbankselect -o - -debug-only=legalizer

Legalize Machine IR for: f
=== New Iteration ===
Legalizing: %4:_(<2 x s16>) = G_INSERT_VECTOR_ELT %1:_, %5:_(s16), %6:_(s32)
.. Unable to legalize
LLVM ERROR: unable to legalize instruction: %4:_(<2 x s16>) = G_INSERT_VECTOR_ELT %1:_, %5:_(s16), %6:_(s32) (in function: f)
PLEASE submit a bug report to https://github.com/llvm/llvm-project/issues/ and include the crash backtrace.
Stack dump:

[llvmbot]

@llvm/issue-subscribers-backend-aarch64

[tschuett]

https://reviews.llvm.org/D155274

[vfdff]

I find this case is crashed with new fail：https://gcc.godbolt.org/z/e3Wq9Mdar

LLVM ERROR: unable to legalize instruction: %7:_(<2 x s32>) = G_ANYEXT %17:_(<2 x s16>) (in function: f)