[llvm] [VPlan] Model first memory runtime checks as VPlan recipes. (PR #221483)

[David Sherwood via llvm-commits]

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@@ -1821,8 +1811,33 @@ class GeneratedRTChecks {
   }
 
   /// Return true if any runtime checks have been added
-  bool hasChecks() const {
-    return getSCEVChecks().first || getMemRuntimeChecks().first;
+  bool hasChecks() const { return getSCEVChecks().first || HasMemChecks; }
+
+  /// Drop the pre-built memory check block in favour of VPlan recipes.
+  /// TODO: Remove once the checks can be costed in VPlan, before VF selection.
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david-arm wrote:

If I've understood correctly, `getCost` will still be based on the original expanded IR, not the vplan-folded recipes? And the plan is to update the cost in a follow-on PR?

https://github.com/llvm/llvm-project/pull/221483