[llvm] [VPlan] Introduce m_Cmp; match more compares (PR #154771)

[Luke Lau via llvm-commits]

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@@ -786,6 +786,8 @@ class VPIRFlags {
       I.setNonNeg(NonNegFlags.NonNeg);
       break;
     case OperationType::Cmp:
+      cast<CmpInst>(I).setPredicate(CmpPredicate);
+      break;
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lukel97 wrote:

Just double checking, this doesn't fix any other existing tests in tree? 

https://github.com/llvm/llvm-project/pull/154771