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

[Florian Hahn via llvm-commits]

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@@ -0,0 +1,161 @@
+; NOTE: Assertions have been autogenerated by utils/update_test_checks.py UTC_ARGS: --version 4
+; RUN: opt -passes=loop-vectorize -force-vector-interleave=1 -force-target-instruction-cost=1 -S < %s | FileCheck %s --check-prefix=CHECK-NODOTPROD
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fhahn wrote:

Yes, IIUC the new `CHECK-NODOTPROD` is there to guard against the issue @david-arm pointed out with TTI. For that, a single test would probably be sufficient (in a separate file). And then remove the line from the other tests again.

Ideally also remove `-force-target-instruction-cost` if possible now that we have a separate file for fix-width tests?

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