[llvm] [VPlan] Relax type of DerivedIV start value (NFC) (PR #206464)

[Florian Hahn via llvm-commits]

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@@ -329,6 +329,13 @@ bool VPlanVerifier::verifyVPBasicBlock(const VPBasicBlock *VPBB) {
         break;
       }
     }
+    if (const auto *DIV = dyn_cast<VPDerivedIVRecipe>(&R)) {
+      if (!DIV->getStartValue()->isDefinedOutsideLoopRegions()) {
+        errs() << "VPDerivedIVRecipe must have start value defined outside "
+                  "loop regions\n";
+        return false;
+      }
+    }
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fhahn wrote:

could you also add a brief test to the existing verifier unit tests?

https://github.com/llvm/llvm-project/pull/206464