include/llvm/CodeGen/EdgeBundles.h

   1 //===-------- EdgeBundles.h - Bundles of CFG edges --------------*- 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 // The EdgeBundles analysis forms equivalence classes of CFG edges such that all
  10 // edges leaving a machine basic block are in the same bundle, and all edges
  11 // leaving a basic block are in the same bundle.
  12 //
  13 //===----------------------------------------------------------------------===//
  14
  15 #ifndef LLVM_CODEGEN_EDGEBUNDLES_H
  16 #define LLVM_CODEGEN_EDGEBUNDLES_H
  17
  18 #include "llvm/ADT/ArrayRef.h"
  19 #include "llvm/ADT/IntEqClasses.h"
  20 #include "llvm/ADT/Twine.h"
  21 #include "llvm/CodeGen/MachineFunctionPass.h"
  22
  23 namespace llvm {
  24
  25 class EdgeBundles : public MachineFunctionPass {
  26   const MachineFunction *MF;
  27
  28   /// EC - Each edge bundle is an equivalence class. The keys are:
  29   ///   2*BB->getNumber()   -> Ingoing bundle.
  30   ///   2*BB->getNumber()+1 -> Outgoing bundle.
  31   IntEqClasses EC;
  32
  33   /// Blocks - Map each bundle to a list of basic block numbers.
  34   SmallVector<SmallVector<unsigned, 8>, 4> Blocks;
  35
  36 public:
  37   static char ID;
  38   EdgeBundles() : MachineFunctionPass(ID) {}
  39
  40   /// getBundle - Return the ingoing (Out = false) or outgoing (Out = true)
  41   /// bundle number for basic block #N
  42   unsigned getBundle(unsigned N, bool Out) const { return EC[2 * N + Out]; }
  43
  44   /// getNumBundles - Return the total number of bundles in the CFG.
  45   unsigned getNumBundles() const { return EC.getNumClasses(); }
  46
  47   /// getBlocks - Return an array of blocks that are connected to Bundle.
  48   ArrayRef<unsigned> getBlocks(unsigned Bundle) const { return Blocks[Bundle]; }
  49
  50   /// getMachineFunction - Return the last machine function computed.
  51   const MachineFunction *getMachineFunction() const { return MF; }
  52
  53   /// view - Visualize the annotated bipartite CFG with Graphviz.
  54   void view() const;
  55
  56 private:
  57   bool runOnMachineFunction(MachineFunction&) override;
  58   void getAnalysisUsage(AnalysisUsage&) const override;
  59 };
  60
  61 } // end namespace llvm
  62
  63 #endif