[llvm] [FuncSpec] Query SCCPSolver in more places (PR #114964)

[Alexandros Lamprineas via llvm-commits]

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@@ -312,10 +317,10 @@ bool InstCostVisitor::discoverTransitivelyIncomingValues(
 
       // Disregard self-references and dead incoming values.
       if (auto *Inst = dyn_cast<Instruction>(V))
-        if (Inst == PN || DeadBlocks.contains(PN->getIncomingBlock(I)))
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labrinea wrote:

> Would that suggest a bug then?

No it's not a bug.

>  Is there a way for the solver and InstCostVisitor to reuse the same code that finds a basic block dead?

I am not sure I understand the question. The InstCostVisitor is a simplified version of the Solver for the pursposes of estimating the profitability of specialization. If the specialization is performed the Solver will end up matching the findings of InstCostVisitor.

https://github.com/llvm/llvm-project/pull/114964