[llvm] [VPlan] Don't use the legacy cost model for loop conditions (PR #156864)

[David Sherwood via llvm-commits]

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@@ -1117,6 +1117,29 @@ InstructionCost VPInstruction::computeCost(ElementCount VF,
     return Ctx.TTI.getIndexedVectorInstrCostFromEnd(Instruction::ExtractElement,
                                                     VecTy, Ctx.CostKind, 0);
   }
+  case VPInstruction::BranchOnCount: {
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david-arm wrote:

I think BranchOnCond needs adding too.

https://github.com/llvm/llvm-project/pull/156864