1//===-- MBlazeMachineFunctionInfo.h - Private data --------------*- 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 MBlaze specific subclass of MachineFunctionInfo.
11//
12//===----------------------------------------------------------------------===//
13
14#ifndef MBLAZE_MACHINE_FUNCTION_INFO_H
15#define MBLAZE_MACHINE_FUNCTION_INFO_H
16
17#include "llvm/ADT/DenseMap.h"
18#include "llvm/ADT/SmallVector.h"
19#include "llvm/CodeGen/MachineFunction.h"
20#include "llvm/CodeGen/MachineFrameInfo.h"
21
22namespace llvm {
23
24/// MBlazeFunctionInfo - This class is derived from MachineFunction private
25/// MBlaze target-specific information for each MachineFunction.
26class MBlazeFunctionInfo : public MachineFunctionInfo {
27  virtual void anchor();
28
29  /// Holds for each function where on the stack the Frame Pointer must be
30  /// saved. This is used on Prologue and Epilogue to emit FP save/restore
31  int FPStackOffset;
32
33  /// Holds for each function where on the stack the Return Address must be
34  /// saved. This is used on Prologue and Epilogue to emit RA save/restore
35  int RAStackOffset;
36
37  /// MBlazeFIHolder - Holds a FrameIndex and it's Stack Pointer Offset
38  struct MBlazeFIHolder {
39
40    int FI;
41    int SPOffset;
42
43    MBlazeFIHolder(int FrameIndex, int StackPointerOffset)
44      : FI(FrameIndex), SPOffset(StackPointerOffset) {}
45  };
46
47  /// When PIC is used the GP must be saved on the stack on the function
48  /// prologue and must be reloaded from this stack location after every
49  /// call. A reference to its stack location and frame index must be kept
50  /// to be used on emitPrologue and processFunctionBeforeFrameFinalized.
51  MBlazeFIHolder GPHolder;
52
53  /// On LowerFormalArguments the stack size is unknown, so the Stack
54  /// Pointer Offset calculation of "not in register arguments" must be
55  /// postponed to emitPrologue.
56  SmallVector<MBlazeFIHolder, 16> FnLoadArgs;
57  bool HasLoadArgs;
58
59  // When VarArgs, we must write registers back to caller stack, preserving
60  // on register arguments. Since the stack size is unknown on
61  // LowerFormalArguments, the Stack Pointer Offset calculation must be
62  // postponed to emitPrologue.
63  SmallVector<MBlazeFIHolder, 4> FnStoreVarArgs;
64  bool HasStoreVarArgs;
65
66  // When determining the final stack layout some of the frame indexes may
67  // be replaced by new frame indexes that reside in the caller's stack
68  // frame. The replacements are recorded in this structure.
69  DenseMap<int,int> FIReplacements;
70
71  /// SRetReturnReg - Some subtargets require that sret lowering includes
72  /// returning the value of the returned struct in a register. This field
73  /// holds the virtual register into which the sret argument is passed.
74  unsigned SRetReturnReg;
75
76  /// GlobalBaseReg - keeps track of the virtual register initialized for
77  /// use as the global base register. This is used for PIC in some PIC
78  /// relocation models.
79  unsigned GlobalBaseReg;
80
81  // VarArgsFrameIndex - FrameIndex for start of varargs area.
82  int VarArgsFrameIndex;
83
84  /// LiveInFI - keeps track of the frame indexes in a callers stack
85  /// frame that are live into a function.
86  SmallVector<int, 16> LiveInFI;
87
88public:
89  MBlazeFunctionInfo(MachineFunction& MF)
90  : FPStackOffset(0), RAStackOffset(0), GPHolder(-1,-1), HasLoadArgs(false),
91    HasStoreVarArgs(false), SRetReturnReg(0), GlobalBaseReg(0),
92    VarArgsFrameIndex(0), LiveInFI()
93  {}
94
95  int getFPStackOffset() const { return FPStackOffset; }
96  void setFPStackOffset(int Off) { FPStackOffset = Off; }
97
98  int getRAStackOffset() const { return RAStackOffset; }
99  void setRAStackOffset(int Off) { RAStackOffset = Off; }
100
101  int getGPStackOffset() const { return GPHolder.SPOffset; }
102  int getGPFI() const { return GPHolder.FI; }
103  void setGPStackOffset(int Off) { GPHolder.SPOffset = Off; }
104  void setGPFI(int FI) { GPHolder.FI = FI; }
105  bool needGPSaveRestore() const { return GPHolder.SPOffset != -1; }
106
107  bool hasLoadArgs() const { return HasLoadArgs; }
108  bool hasStoreVarArgs() const { return HasStoreVarArgs; }
109
110  void recordLiveIn(int FI) {
111    LiveInFI.push_back(FI);
112  }
113
114  bool isLiveIn(int FI) {
115    for (unsigned i = 0, e = LiveInFI.size(); i < e; ++i)
116      if (FI == LiveInFI[i]) return true;
117
118    return false;
119  }
120
121  const SmallVector<int, 16>& getLiveIn() const { return LiveInFI; }
122
123  void recordReplacement(int OFI, int NFI) {
124    FIReplacements.insert(std::make_pair(OFI,NFI));
125  }
126
127  bool hasReplacement(int OFI) const {
128    return FIReplacements.find(OFI) != FIReplacements.end();
129  }
130
131  int getReplacement(int OFI) const {
132    return FIReplacements.lookup(OFI);
133  }
134
135  void recordLoadArgsFI(int FI, int SPOffset) {
136    if (!HasLoadArgs) HasLoadArgs=true;
137    FnLoadArgs.push_back(MBlazeFIHolder(FI, SPOffset));
138  }
139
140  void recordStoreVarArgsFI(int FI, int SPOffset) {
141    if (!HasStoreVarArgs) HasStoreVarArgs=true;
142    FnStoreVarArgs.push_back(MBlazeFIHolder(FI, SPOffset));
143  }
144
145  void adjustLoadArgsFI(MachineFrameInfo *MFI) const {
146    if (!hasLoadArgs()) return;
147    for (unsigned i = 0, e = FnLoadArgs.size(); i != e; ++i)
148      MFI->setObjectOffset(FnLoadArgs[i].FI, FnLoadArgs[i].SPOffset);
149  }
150
151  void adjustStoreVarArgsFI(MachineFrameInfo *MFI) const {
152    if (!hasStoreVarArgs()) return;
153    for (unsigned i = 0, e = FnStoreVarArgs.size(); i != e; ++i)
154      MFI->setObjectOffset(FnStoreVarArgs[i].FI, FnStoreVarArgs[i].SPOffset);
155  }
156
157  unsigned getSRetReturnReg() const { return SRetReturnReg; }
158  void setSRetReturnReg(unsigned Reg) { SRetReturnReg = Reg; }
159
160  unsigned getGlobalBaseReg() const { return GlobalBaseReg; }
161  void setGlobalBaseReg(unsigned Reg) { GlobalBaseReg = Reg; }
162
163  int getVarArgsFrameIndex() const { return VarArgsFrameIndex; }
164  void setVarArgsFrameIndex(int Index) { VarArgsFrameIndex = Index; }
165};
166
167} // end of namespace llvm
168
169#endif // MBLAZE_MACHINE_FUNCTION_INFO_H
170