[llvm] [LoopVectorizer] Add support for partial reductions (PR #92418)

[Sam Tebbs via llvm-commits]

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@@ -0,0 +1,1455 @@
+; NOTE: Assertions have been autogenerated by utils/update_test_checks.py UTC_ARGS: --version 4
+; RUN: opt -passes=loop-vectorize -force-vector-interleave=1 -enable-epilogue-vectorization=false -force-target-instruction-cost=1 -S < %s | FileCheck %s --check-prefixes=CHECK-INTERLEAVE1
+; RUN: opt -passes=loop-vectorize -force-target-instruction-cost=1 -enable-epilogue-vectorization=false -S < %s | FileCheck %s --check-prefixes=CHECK-INTERLEAVED
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SamTebbs33 wrote:

They do need this until the max vector bandwidth patch is re-landed. I will remove this once that has happened.

https://github.com/llvm/llvm-project/pull/92418