[llvm-branch-commits] [llvm] [LV] Mask off possibly aliasing vector lanes (PR #100579)

[Sander de Smalen via llvm-branch-commits]

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@@ -974,6 +974,11 @@ AArch64TTIImpl::getIntrinsicInstrCost(const IntrinsicCostAttributes &ICA,
     }
     break;
   }
+  case Intrinsic::loop_dependence_raw_mask:
+  case Intrinsic::loop_dependence_war_mask:
+    if (ST->hasSVE2())
+      return 1;
+    return InstructionCost::getInvalid(CostKind);
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sdesmalen-arm wrote:

I would suggest reverting to calling the default cost-model here by doing `break;`.

To the question whether to return either an Invalid or a high cost in the default cost-model, I would argue for a high cost because that would allow for testing the feature without requiring the special instructions.

https://github.com/llvm/llvm-project/pull/100579