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

[Sam Tebbs via llvm-commits]

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@@ -324,26 +324,19 @@ void VPPartialReductionRecipe::execute(VPTransformState &State) {
 
   assert(Opcode == Instruction::Add && "Unhandled partial reduction opcode");
 
-  SmallVector<VPValue *, 2> Operands;
-  for (auto *Op : operands())
-    Operands.push_back(Op);
+  Value *BinOpVal = State.get(getOperand(0), 0);
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SamTebbs33 wrote:

That's a good idea. I've added an assertion on operand 1 to make sure it's a phi because we're a bit more flexible with what the other operand is.

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