MBlazeMachineFunction.h revision 204642 
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/SmallVector.h"
18#include "llvm/ADT/VectorExtras.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
28private:
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  /// At each function entry a special bitmask directive must be emitted
38  /// to help in debugging CPU callee saved registers. It needs a negative
39  /// offset from the final stack size and its higher register location on
40  /// the stack.
41  int CPUTopSavedRegOff;
42
43  /// MBlazeFIHolder - Holds a FrameIndex and it's Stack Pointer Offset
44  struct MBlazeFIHolder {
45
46    int FI;
47    int SPOffset;
48
49    MBlazeFIHolder(int FrameIndex, int StackPointerOffset)
50      : FI(FrameIndex), SPOffset(StackPointerOffset) {}
51  };
52
53  /// When PIC is used the GP must be saved on the stack on the function
54  /// prologue and must be reloaded from this stack location after every
55  /// call. A reference to its stack location and frame index must be kept
56  /// to be used on emitPrologue and processFunctionBeforeFrameFinalized.
57  MBlazeFIHolder GPHolder;
58
59  /// On LowerFormalArguments the stack size is unknown, so the Stack
60  /// Pointer Offset calculation of "not in register arguments" must be
61  /// postponed to emitPrologue.
62  SmallVector<MBlazeFIHolder, 16> FnLoadArgs;
63  bool HasLoadArgs;
64
65  // When VarArgs, we must write registers back to caller stack, preserving
66  // on register arguments. Since the stack size is unknown on
67  // LowerFormalArguments, the Stack Pointer Offset calculation must be
68  // postponed to emitPrologue.
69  SmallVector<MBlazeFIHolder, 4> FnStoreVarArgs;
70  bool HasStoreVarArgs;
71
72  /// SRetReturnReg - Some subtargets require that sret lowering includes
73  /// returning the value of the returned struct in a register. This field
74  /// holds the virtual register into which the sret argument is passed.
75  unsigned SRetReturnReg;
76
77  /// GlobalBaseReg - keeps track of the virtual register initialized for
78  /// use as the global base register. This is used for PIC in some PIC
79  /// relocation models.
80  unsigned GlobalBaseReg;
81
82public:
83  MBlazeFunctionInfo(MachineFunction& MF)
84  : FPStackOffset(0), RAStackOffset(0), CPUTopSavedRegOff(0),
85    GPHolder(-1,-1), HasLoadArgs(false), HasStoreVarArgs(false),
86    SRetReturnReg(0), GlobalBaseReg(0)
87  {}
88
89  int getFPStackOffset() const { return FPStackOffset; }
90  void setFPStackOffset(int Off) { FPStackOffset = Off; }
91
92  int getRAStackOffset() const { return RAStackOffset; }
93  void setRAStackOffset(int Off) { RAStackOffset = Off; }
94
95  int getCPUTopSavedRegOff() const { return CPUTopSavedRegOff; }
96  void setCPUTopSavedRegOff(int Off) { CPUTopSavedRegOff = Off; }
97
98  int getGPStackOffset() const { return GPHolder.SPOffset; }
99  int getGPFI() const { return GPHolder.FI; }
100  void setGPStackOffset(int Off) { GPHolder.SPOffset = Off; }
101  void setGPFI(int FI) { GPHolder.FI = FI; }
102  bool needGPSaveRestore() const { return GPHolder.SPOffset != -1; }
103
104  bool hasLoadArgs() const { return HasLoadArgs; }
105  bool hasStoreVarArgs() const { return HasStoreVarArgs; }
106
107  void recordLoadArgsFI(int FI, int SPOffset) {
108    if (!HasLoadArgs) HasLoadArgs=true;
109    FnLoadArgs.push_back(MBlazeFIHolder(FI, SPOffset));
110  }
111  void recordStoreVarArgsFI(int FI, int SPOffset) {
112    if (!HasStoreVarArgs) HasStoreVarArgs=true;
113    FnStoreVarArgs.push_back(MBlazeFIHolder(FI, SPOffset));
114  }
115
116  void adjustLoadArgsFI(MachineFrameInfo *MFI) const {
117    if (!hasLoadArgs()) return;
118    for (unsigned i = 0, e = FnLoadArgs.size(); i != e; ++i)
119      MFI->setObjectOffset( FnLoadArgs[i].FI, FnLoadArgs[i].SPOffset );
120  }
121  void adjustStoreVarArgsFI(MachineFrameInfo *MFI) const {
122    if (!hasStoreVarArgs()) return;
123    for (unsigned i = 0, e = FnStoreVarArgs.size(); i != e; ++i)
124      MFI->setObjectOffset( FnStoreVarArgs[i].FI, FnStoreVarArgs[i].SPOffset );
125  }
126
127  unsigned getSRetReturnReg() const { return SRetReturnReg; }
128  void setSRetReturnReg(unsigned Reg) { SRetReturnReg = Reg; }
129
130  unsigned getGlobalBaseReg() const { return GlobalBaseReg; }
131  void setGlobalBaseReg(unsigned Reg) { GlobalBaseReg = Reg; }
132};
133
134} // end of namespace llvm
135
136#endif // MBLAZE_MACHINE_FUNCTION_INFO_H
137