1 //===-- llvm/CodeGen/Splitter.h - Splitter -*- C++ -*----------------------===//
2 //
3 //                     The LLVM Compiler Infrastructure
4 //
5 // This file is distributed under the University of Illinois Open Source
6 // License. See LICENSE.TXT for details.
7 //
8 //===----------------------------------------------------------------------===//
9 
10 #ifndef LLVM_CODEGEN_SPLITTER_H
11 #define LLVM_CODEGEN_SPLITTER_H
12 
13 #include "llvm/CodeGen/MachineFunctionPass.h"
14 #include "llvm/CodeGen/MachineLoopInfo.h"
15 #include "llvm/CodeGen/SlotIndexes.h"
16 
17 #include <deque>
18 #include <map>
19 #include <string>
20 #include <vector>
21 
22 namespace llvm {
23 
24   class LiveInterval;
25   class LiveIntervals;
26   struct LiveRange;
27   class LoopSplit;
28   class MachineDominatorTree;
29   class MachineRegisterInfo;
30   class SlotIndexes;
31   class TargetInstrInfo;
32   class VNInfo;
33 
34   class LoopSplitter : public MachineFunctionPass {
35     friend class LoopSplit;
36   public:
37     static char ID;
38 
LoopSplitter()39     LoopSplitter() : MachineFunctionPass(ID) {
40       initializeLoopSplitterPass(*PassRegistry::getPassRegistry());
41     }
42 
43     virtual void getAnalysisUsage(AnalysisUsage &au) const;
44 
45     virtual bool runOnMachineFunction(MachineFunction &fn);
46 
47     virtual void releaseMemory();
48 
49 
50   private:
51 
52     MachineFunction *mf;
53     LiveIntervals *lis;
54     MachineLoopInfo *mli;
55     MachineRegisterInfo *mri;
56     MachineDominatorTree *mdt;
57     SlotIndexes *sis;
58     const TargetInstrInfo *tii;
59     const TargetRegisterInfo *tri;
60 
61     std::string fqn;
62     std::deque<LiveInterval*> intervals;
63 
64     typedef std::pair<SlotIndex, SlotIndex> SlotPair;
65     typedef std::vector<SlotPair> LoopRanges;
66     typedef std::map<MachineLoop*, LoopRanges> LoopRangeMap;
67     LoopRangeMap loopRangeMap;
68 
69     void dumpLoopInfo(MachineLoop &loop);
70 
71     void dumpOddTerminators();
72 
73     void updateTerminators(MachineBasicBlock &mbb);
74 
75     bool canInsertPreHeader(MachineLoop &loop);
76     MachineBasicBlock& insertPreHeader(MachineLoop &loop);
77 
78     bool isCriticalEdge(MachineLoop::Edge &edge);
79     bool canSplitEdge(MachineLoop::Edge &edge);
80     MachineBasicBlock& splitEdge(MachineLoop::Edge &edge, MachineLoop &loop);
81 
82     LoopRanges& getLoopRanges(MachineLoop &loop);
83     std::pair<bool, SlotPair> getLoopSubRange(const LiveRange &lr,
84                                               MachineLoop &loop);
85 
86     void dumpLoopRanges(MachineLoop &loop);
87 
88     void processHeader(LoopSplit &split);
89     void processLoopExits(LoopSplit &split);
90     void processLoopUses(LoopSplit &split);
91 
92     bool splitOverLoop(LiveInterval &li, MachineLoop &loop);
93 
94     void processInterval(LiveInterval &li);
95 
96     void processIntervals();
97   };
98 
99 }
100 
101 #endif
102