[llvm] [VPlan] Add poisoning value handle for VPValue. (NFCI) (PR #185054)

[Luke Lau via llvm-commits]

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@@ -152,6 +152,62 @@ VPRecipeValue::~VPRecipeValue() {
   Def->removeDefinedValue(this);
 }
 
+#if LLVM_ENABLE_ABI_BREAKING_CHECKS && !defined(NDEBUG)
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lukel97 wrote:

How come we need LLVM_ENABLE_ABI_BREAKING_CHECKS? Does VPValue form part of the C++ ABI? I thought it was internal to the loop vectorizer

https://github.com/llvm/llvm-project/pull/185054