SuccessChanges

Summary

  1. [NFC] [PowerPC] Update vec_constants test to reflect more patterns (details)
  2. [NFC] [PowerPC] Remove dead code in BUILD_VECTOR peephole (details)
Commit 48340fbe6a1a126298c4fe16dcd186d94e485203 by qiucofan
[NFC] [PowerPC] Update vec_constants test to reflect more patterns

This patch uses update_llc_check script to update vec_constants.ll, and
add two cases to cover 'vsplti+vsldoi' with 16-bit and 24-bit offset.
The file was modifiedllvm/test/CodeGen/PowerPC/vec_constants.ll
Commit b6c8feb29fce39121884f7e08ec6eb0f58da3fb7 by qiucofan
[NFC] [PowerPC] Remove dead code in BUILD_VECTOR peephole

The piece of code tries to use splat+shift to lower build_vector with
repeating bit pattern. And immediate field of vector splat is only 5
bits (-16~15). It iterates over them one by one to find which
shifts/rotates to number in build_vector.

This patch removes code to try matching constant with algebraic
right-shift because that's meaningless - any negative number's algebraic
right-shift won't produce result smaller than itself. Besides, code
(int)((unsigned)i >> j) means logical shift-right in C.

Reviewed By: RKSimon

Differential Revision: https://reviews.llvm.org/D93937
The file was modifiedllvm/lib/Target/PowerPC/PPCISelLowering.cpp