HexagonSubtarget.h revision 309124 
1//===-- HexagonSubtarget.h - Define Subtarget for the Hexagon ---*- 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// This file declares the Hexagon specific subclass of TargetSubtarget.
11//
12//===----------------------------------------------------------------------===//
13
14#ifndef LLVM_LIB_TARGET_HEXAGON_HEXAGONSUBTARGET_H
15#define LLVM_LIB_TARGET_HEXAGON_HEXAGONSUBTARGET_H
16
17#include "HexagonFrameLowering.h"
18#include "HexagonISelLowering.h"
19#include "HexagonInstrInfo.h"
20#include "HexagonSelectionDAGInfo.h"
21#include "llvm/Target/TargetMachine.h"
22#include "llvm/Target/TargetSubtargetInfo.h"
23#include <string>
24
25#define GET_SUBTARGETINFO_HEADER
26#include "HexagonGenSubtargetInfo.inc"
27
28#define Hexagon_SMALL_DATA_THRESHOLD 8
29#define Hexagon_SLOTS 4
30
31namespace llvm {
32
33class HexagonSubtarget : public HexagonGenSubtargetInfo {
34  virtual void anchor();
35
36  bool UseMemOps, UseHVXOps, UseHVXDblOps;
37  bool ModeIEEERndNear;
38
39public:
40  enum HexagonArchEnum {
41    V4, V5, V55, V60
42  };
43
44  HexagonArchEnum HexagonArchVersion;
45  /// True if the target should use Back-Skip-Back scheduling. This is the
46  /// default for V60.
47  bool UseBSBScheduling;
48
49  class HexagonDAGMutation : public ScheduleDAGMutation {
50  public:
51    void apply(ScheduleDAGInstrs *DAG) override;
52  };
53
54private:
55  std::string CPUString;
56  HexagonInstrInfo InstrInfo;
57  HexagonTargetLowering TLInfo;
58  HexagonSelectionDAGInfo TSInfo;
59  HexagonFrameLowering FrameLowering;
60  InstrItineraryData InstrItins;
61  void initializeEnvironment();
62
63public:
64  HexagonSubtarget(const Triple &TT, StringRef CPU, StringRef FS,
65                   const TargetMachine &TM);
66
67  /// getInstrItins - Return the instruction itineraries based on subtarget
68  /// selection.
69  const InstrItineraryData *getInstrItineraryData() const override {
70    return &InstrItins;
71  }
72  const HexagonInstrInfo *getInstrInfo() const override { return &InstrInfo; }
73  const HexagonRegisterInfo *getRegisterInfo() const override {
74    return &InstrInfo.getRegisterInfo();
75  }
76  const HexagonTargetLowering *getTargetLowering() const override {
77    return &TLInfo;
78  }
79  const HexagonFrameLowering *getFrameLowering() const override {
80    return &FrameLowering;
81  }
82  const HexagonSelectionDAGInfo *getSelectionDAGInfo() const override {
83    return &TSInfo;
84  }
85
86  HexagonSubtarget &initializeSubtargetDependencies(StringRef CPU,
87                                                    StringRef FS);
88
89  /// ParseSubtargetFeatures - Parses features string setting specified
90  /// subtarget options.  Definition of function is auto generated by tblgen.
91  void ParseSubtargetFeatures(StringRef CPU, StringRef FS);
92
93  bool useMemOps() const { return UseMemOps; }
94  bool hasV5TOps() const { return getHexagonArchVersion() >= V5; }
95  bool hasV5TOpsOnly() const { return getHexagonArchVersion() == V5; }
96  bool hasV55TOps() const { return getHexagonArchVersion() >= V55; }
97  bool hasV55TOpsOnly() const { return getHexagonArchVersion() == V55; }
98  bool hasV60TOps() const { return getHexagonArchVersion() >= V60; }
99  bool hasV60TOpsOnly() const { return getHexagonArchVersion() == V60; }
100  bool modeIEEERndNear() const { return ModeIEEERndNear; }
101  bool useHVXOps() const { return UseHVXOps; }
102  bool useHVXDblOps() const { return UseHVXOps && UseHVXDblOps; }
103  bool useHVXSglOps() const { return UseHVXOps && !UseHVXDblOps; }
104
105  bool useBSBScheduling() const { return UseBSBScheduling; }
106  bool enableMachineScheduler() const override;
107  // Always use the TargetLowering default scheduler.
108  // FIXME: This will use the vliw scheduler which is probably just hurting
109  // compiler time and will be removed eventually anyway.
110  bool enableMachineSchedDefaultSched() const override { return false; }
111
112  AntiDepBreakMode getAntiDepBreakMode() const override { return ANTIDEP_ALL; }
113  bool enablePostRAScheduler() const override { return true; }
114
115  bool enableSubRegLiveness() const override;
116
117  const std::string &getCPUString () const { return CPUString; }
118
119  // Threshold for small data section
120  unsigned getSmallDataThreshold() const {
121    return Hexagon_SMALL_DATA_THRESHOLD;
122  }
123  const HexagonArchEnum &getHexagonArchVersion() const {
124    return HexagonArchVersion;
125  }
126
127  void getPostRAMutations(
128      std::vector<std::unique_ptr<ScheduleDAGMutation>> &Mutations)
129      const override;
130
131  /// \brief Perform target specific adjustments to the latency of a schedule
132  /// dependency.
133  void adjustSchedDependency(SUnit *def, SUnit *use, SDep& dep) const override;
134
135private:
136  // Helper function responsible for increasing the latency only.
137  void updateLatency(MachineInstr *SrcInst, MachineInstr *DstInst, SDep &Dep)
138      const;
139  void changeLatency(SUnit *Src, SmallVector<SDep, 4> &Deps, SUnit *Dst,
140      unsigned Lat) const;
141  bool isBestZeroLatency(SUnit *Src, SUnit *Dst, const HexagonInstrInfo *TII)
142      const;
143  void changePhiLatency(MachineInstr *SrcInst, SUnit *Dst, SDep &Dep) const;
144};
145
146} // end namespace llvm
147
148#endif
149