[llvm] [LV] Add ExtNegatedMulAccReduction expression type (PR #160154)

[Sam Tebbs via llvm-commits]

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@@ -3524,7 +3524,13 @@ tryToMatchAndCreateMulAccumulateReduction(VPReductionRecipe *Red,
   };
 
   VPValue *VecOp = Red->getVecOp();
+  VPValue *Sub = nullptr;
   VPValue *A, *B;
+  // Sub reductions could have a sub between the add reduction and vec op.
+  if (match(VecOp, m_Binary<Instruction::Sub>(m_SpecificInt(0), m_VPValue()))) {
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SamTebbs33 wrote:

That's nice, done.

https://github.com/llvm/llvm-project/pull/160154