[SelectionDAG] Add llvm.vector.{extract,insert} intrinsics

Authored by joechrisellis on Dec 9 2020, 3:05 AM.


[SelectionDAG] Add llvm.vector.{extract,insert} intrinsics

This commit adds two new intrinsics.

  • llvm.experimental.vector.insert: used to insert a vector into another vector starting at a given index.
  • llvm.experimental.vector.extract: used to extract a subvector from a larger vector starting from a given index.

The codegen work for these intrinsics has already been completed; this
commit is simply exposing the existing ISD nodes to LLVM IR.

Reviewed By: cameron.mcinally

Differential Revision: https://reviews.llvm.org/D91362