[PATCH] D136332: [FuncSpec][NFC] Avoid redundant computations of DominatorTree/LoopInfo

[Sjoerd Meijer via Phabricator via llvm-commits]

SjoerdMeijer added inline comments.


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Comment at: llvm/lib/Transforms/IPO/FunctionSpecialization.cpp:467
         SpecializationInfo &S = Specializations.back().second;
-        S.Gain += getSpecializationBonus(A, C);
+        S.Gain += getSpecializationBonus(A, C, LI);
         S.Args.push_back({A, C});
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Nit: if this is a simple getter function, not calculating anything, we can just pass `Solver.getLoopInfo(*F)` in here. 


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Comment at: llvm/lib/Transforms/Utils/SCCPSolver.cpp:342-347
+  const LoopInfo &getLoopInfo(Function &F) {
+    auto A = AnalysisResults.find(&F);
+    assert(A != AnalysisResults.end() && A->second.LI &&
+           "Need LoopInfo analysis results for function.");
+    return *A->second.LI;
+  }
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ChuanqiXu wrote:
> I feel like the assertion may be triggered if we run specializer on the specialized functions. This **looks** possible when `FuncSpecializationMaxIters>1` but we only calculate the analysis once.
Or with the legacy pass manager? Is that how I should read the comment above:

  // We cannot preserve the LI, DT, or PDT with the legacy pass ...


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https://reviews.llvm.org/D136332