[llvm] [SCEV] Add dedicated AffineAddRec matcher + loop matchers (NFC). (PR #141141)

[Nikita Popov via llvm-commits]

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@@ -808,7 +808,8 @@ static bool isLoopCounter(PHINode* Phi, Loop *L,
     return false;
 
   const SCEV *S = SE->getSCEV(Phi);
-  if (!match(S, m_scev_AffineAddRec(m_SCEV(), m_scev_One())) ||
+  if (!match(S,
+             m_scev_AffineAddRec(m_SCEV(), m_scev_One(), m_SpecificLoop(L))) ||
       cast<SCEVAddRecExpr>(S)->getLoop() != L)
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nikic wrote:

Should drop this check now.

https://github.com/llvm/llvm-project/pull/141141