llvm/lib/Target/WebAssembly/WebAssemblySortRegion.h

   1 //===-- WebAssemblySortRegion.h - WebAssembly Sort SortRegion ----*- 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 /// \file
  10 /// \brief This file implements regions used in CFGSort and CFGStackify.
  11 ///
  12 //===----------------------------------------------------------------------===//
  13
  14 #ifndef LLVM_LIB_TARGET_WEBASSEMBLY_WEBASSEMBLYSORTREGION_H
  15 #define LLVM_LIB_TARGET_WEBASSEMBLY_WEBASSEMBLYSORTREGION_H
  16
  17 #include "llvm/ADT/ArrayRef.h"
  18 #include "llvm/ADT/DenseMap.h"
  19 #include "llvm/ADT/iterator_range.h"
  20
  21 namespace llvm {
  22
  23 class MachineBasicBlock;
  24 class MachineLoop;
  25 class MachineLoopInfo;
  26 class WebAssemblyException;
  27 class WebAssemblyExceptionInfo;
  28
  29 namespace WebAssembly {
  30
  31 // Wrapper for loops and exceptions
  32 class SortRegion {
  33 public:
  34   virtual ~SortRegion() = default;
  35   virtual MachineBasicBlock *getHeader() const = 0;
  36   virtual bool contains(const MachineBasicBlock *MBB) const = 0;
  37   virtual unsigned getNumBlocks() const = 0;
  38   using block_iterator = typename ArrayRef<MachineBasicBlock *>::const_iterator;
  39   virtual iterator_range<block_iterator> blocks() const = 0;
  40   virtual bool isLoop() const = 0;
  41 };
  42
  43 template <typename T> class ConcreteSortRegion : public SortRegion {
  44   const T *Unit;
  45
  46 public:
  47   ConcreteSortRegion(const T *Unit) : Unit(Unit) {}
  48   MachineBasicBlock *getHeader() const override { return Unit->getHeader(); }
  49   bool contains(const MachineBasicBlock *MBB) const override {
  50     return Unit->contains(MBB);
  51   }
  52   unsigned getNumBlocks() const override { return Unit->getNumBlocks(); }
  53   iterator_range<block_iterator> blocks() const override {
  54     return Unit->blocks();
  55   }
  56   bool isLoop() const override { return false; }
  57 };
  58
  59 // This class has information of nested SortRegions; this is analogous to what
  60 // LoopInfo is for loops.
  61 class SortRegionInfo {
  62   friend class ConcreteSortRegion<MachineLoopInfo>;
  63   friend class ConcreteSortRegion<WebAssemblyException>;
  64
  65   const MachineLoopInfo &MLI;
  66   const WebAssemblyExceptionInfo &WEI;
  67   DenseMap<const MachineLoop *, std::unique_ptr<SortRegion>> LoopMap;
  68   DenseMap<const WebAssemblyException *, std::unique_ptr<SortRegion>>
  69       ExceptionMap;
  70
  71 public:
  72   SortRegionInfo(const MachineLoopInfo &MLI,
  73                  const WebAssemblyExceptionInfo &WEI)
  74       : MLI(MLI), WEI(WEI) {}
  75
  76   // Returns a smallest loop or exception that contains MBB
  77   const SortRegion *getRegionFor(const MachineBasicBlock *MBB);
  78
  79   // Return the "bottom" block among all blocks dominated by the region
  80   // (MachineLoop or WebAssemblyException) header. This works when the entity is
  81   // discontiguous.
  82   MachineBasicBlock *getBottom(const SortRegion *R);
  83   MachineBasicBlock *getBottom(const MachineLoop *ML);
  84   MachineBasicBlock *getBottom(const WebAssemblyException *WE);
  85 };
  86
  87 } // end namespace WebAssembly
  88
  89 } // end namespace llvm
  90
  91 #endif