[llvm] [LV] Bundle partial reductions inside VPExpressionRecipe (PR #147302)

[Sam Tebbs via llvm-commits]

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@@ -5526,7 +5526,7 @@ InstructionCost AArch64TTIImpl::getExtendedReductionCost(
   EVT ResVT = TLI->getValueType(DL, ResTy);
 
   if (Opcode == Instruction::Add && VecVT.isSimple() && ResVT.isSimple() &&
-      VecVT.getSizeInBits() >= 64) {
+      VecVT.isFixedLengthVector() && VecVT.getSizeInBits() >= 64) {
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SamTebbs33 wrote:

I think it was to-do with a crash but the tests pass after removing this change, so I've removed it and can re-add it later on if need be.

https://github.com/llvm/llvm-project/pull/147302