[DAGCombine] Add calls to SimplifyDemandedVectorElts from visitINSERT_SUBVECTOR (PR37989)

This uncovered an off-by-one typo in SimplifyDemandedVectorElts's INSERT_SUBVECTOR handling as its bounds check was bailing on safe indices.




git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@347313 91177308-0d34-0410-b5e6-96231b3b80d8
5 files changed