[llvm] [LV] Create in-loop sub reductions (PR #147026)

[Sam Tebbs via llvm-commits]

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@@ -23645,7 +23648,7 @@ class HorizontalReduction {
                 IsSigned);
           Value *Scale = ConstantVector::getSplat(
               EC, ConstantInt::get(DestTy->getScalarType(), Cnt));
-          LLVM_DEBUG(dbgs() << "SLP: Add (to-mul) " << Cnt << "of " << Vec
+          LLVM_DEBUG(dbgs() << "SLP: " << (RdxKind == RecurKind::Add ? "Add" : "Sub") << " (to-mul) " << Cnt << "of " << Vec
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SamTebbs33 wrote:

Done.

https://github.com/llvm/llvm-project/pull/147026