[PATCH] D130740: [TTI][AArch64][SLP] Sets the cost of an ADD reduction 2xi64 to 2.

[Vasileios Porpodas via Phabricator via llvm-commits]

vporpo created this revision.
Herald added subscribers: hiraditya, kristof.beyls.
Herald added a project: All.
vporpo requested review of this revision.
Herald added a project: LLVM.
Herald added a subscriber: llvm-commits.

2xi64 is the legalized type for wide reductions (like 16xi64) and setting the
cost to 2 makes `load-reduce` and `load-zext-reduce` patterns profitable.

The few performance measurments that I did on an aarch64 machine confirm that
these patterns are actually faster when vectorized.


Repository:
  rG LLVM Github Monorepo

https://reviews.llvm.org/D130740

Files:
  llvm/lib/Target/AArch64/AArch64TargetTransformInfo.cpp
  llvm/test/Analysis/CostModel/AArch64/reduce-add.ll
  llvm/test/Transforms/SLPVectorizer/AArch64/reduce-add-i64.ll

-------------- next part --------------
A non-text attachment was scrubbed...
Name: D130740.448496.patch
Type: text/x-patch
Size: 15908 bytes
Desc: not available
URL: <http://lists.llvm.org/pipermail/llvm-commits/attachments/20220729/203c4ac3/attachment.bin>