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

[Alexandros Lamprineas via llvm-commits]

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@@ -347,10 +352,10 @@ Constant *InstCostVisitor::visitPHINode(PHINode &I) {
 
     // Disregard self-references and dead incoming values.
     if (auto *Inst = dyn_cast<Instruction>(V))
-      if (Inst == &I || DeadBlocks.contains(I.getIncomingBlock(Idx)))
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labrinea wrote:

Same here, the InstCostVisitor has more knowledge than the solver when estimating specializations. Can we assert just before inserting to DeadBlocks that the solver thinks the block is executable?

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