[llvm-branch-commits] [llvm] [LoopVectorizer] Bundle partial reductions with different extensions (PR #136997)

[Sam Tebbs via llvm-branch-commits]

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@@ -2438,14 +2438,14 @@ VPMulAccumulateReductionRecipe::computeCost(ElementCount VF,
     return Ctx.TTI.getPartialReductionCost(
         Instruction::Add, Ctx.Types.inferScalarType(getVecOp0()),
         Ctx.Types.inferScalarType(getVecOp1()), getResultType(), VF,
-        TTI::getPartialReductionExtendKind(getExtOpcode()),
-        TTI::getPartialReductionExtendKind(getExtOpcode()), Instruction::Mul);
+        TTI::getPartialReductionExtendKind(getExt0Opcode()),
+        TTI::getPartialReductionExtendKind(getExt1Opcode()), Instruction::Mul);
   }
 
   Type *RedTy = Ctx.Types.inferScalarType(this);
   auto *SrcVecTy =
       cast<VectorType>(toVectorTy(Ctx.Types.inferScalarType(getVecOp0()), VF));
-  return Ctx.TTI.getMulAccReductionCost(isZExt(), RedTy, SrcVecTy,
+  return Ctx.TTI.getMulAccReductionCost(isZExt0(), RedTy, SrcVecTy,
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SamTebbs33 wrote:

I started off by modifying the TTI hook but found that it wasn't actually necessary since only partial reductions make use of the differing signedness and they don't use this hook. If someone is interested in getting mul-acc-reduce generated with different extensions then they can do the investigation needed for costing but I think it's outside the scope of this work.

https://github.com/llvm/llvm-project/pull/136997