include/llvm/Analysis/SyntheticCountsUtils.h

   1 //===- SyntheticCountsUtils.h - utilities for count propagation--*- C++ -*-===//
   2 //
   3 // Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
   4 // See https://llvm.org/LICENSE.txt for license information.
   5 // SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
   6 //
   7 //===----------------------------------------------------------------------===//
   8 //
   9 // This file defines utilities for synthetic counts propagation.
  10 //
  11 //===----------------------------------------------------------------------===//
  12
  13 #ifndef LLVM_ANALYSIS_SYNTHETIC_COUNTS_UTILS_H
  14 #define LLVM_ANALYSIS_SYNTHETIC_COUNTS_UTILS_H
  15
  16 #include "llvm/ADT/STLExtras.h"
  17 #include "llvm/Analysis/CallGraph.h"
  18 #include "llvm/Support/ScaledNumber.h"
  19
  20 namespace llvm {
  21
  22 class CallGraph;
  23 class Function;
  24
  25 /// Class with methods to propagate synthetic entry counts.
  26 ///
  27 /// This class is templated on the type of the call graph and designed to work
  28 /// with the traditional per-module callgraph and the summary callgraphs used in
  29 /// ThinLTO. This contains only static methods and alias templates.
  30 template <typename CallGraphType> class SyntheticCountsUtils {
  31 public:
  32   using Scaled64 = ScaledNumber<uint64_t>;
  33   using CGT = GraphTraits<CallGraphType>;
  34   using NodeRef = typename CGT::NodeRef;
  35   using EdgeRef = typename CGT::EdgeRef;
  36   using SccTy = std::vector<NodeRef>;
  37
  38   // Not all EdgeRef have information about the source of the edge. Hence
  39   // NodeRef corresponding to the source of the EdgeRef is explicitly passed.
  40   using GetProfCountTy = function_ref<Optional<Scaled64>(NodeRef, EdgeRef)>;
  41   using AddCountTy = function_ref<void(NodeRef, Scaled64)>;
  42
  43   static void propagate(const CallGraphType &CG, GetProfCountTy GetProfCount,
  44                         AddCountTy AddCount);
  45
  46 private:
  47   static void propagateFromSCC(const SccTy &SCC, GetProfCountTy GetProfCount,
  48                                AddCountTy AddCount);
  49 };
  50 } // namespace llvm
  51
  52 #endif