MipsMachineFunction.h revision 2d4575ea5aa68465d8440d5cbeeac702ba8114b2 
1//===-- MipsMachineFunctionInfo.h - Private data used for Mips ----*- C++ -*-=//
2//
3//                     The LLVM Compiler Infrastructure
4//
5// This file was developed by Bruno Cardoso Lopes and is distributed under
6// the University of Illinois Open Source License. See LICENSE.TXT for details.
7//
8//===----------------------------------------------------------------------===//
9//
10// This file declares the Mips specific subclass of MachineFunctionInfo.
11//
12//===----------------------------------------------------------------------===//
13
14#ifndef MIPS_MACHINE_FUNCTION_INFO_H
15#define MIPS_MACHINE_FUNCTION_INFO_H
16
17#include "llvm/ADT/VectorExtras.h"
18#include "llvm/CodeGen/MachineFunction.h"
19#include "llvm/CodeGen/MachineFrameInfo.h"
20
21namespace llvm {
22
23/// MipsFunctionInfo - This class is derived from MachineFunction private
24/// Mips target-specific information for each MachineFunction.
25class MipsFunctionInfo : public MachineFunctionInfo {
26
27private:
28  /// Holds for each function where on the stack
29  /// the Frame Pointer must be saved
30  int FPStackOffset;
31
32  /// Holds for each function where on the stack
33  /// the Return Address must be saved
34  int RAStackOffset;
35
36  /// MipsFIHolder - Holds a FrameIndex and it's Stack Pointer Offset
37  struct MipsFIHolder {
38
39    int FI;
40    int SPOffset;
41
42    MipsFIHolder(int FrameIndex, int StackPointerOffset)
43      : FI(FrameIndex), SPOffset(StackPointerOffset) {}
44  };
45
46  // On LowerFORMAL_ARGUMENTS the stack size is unknown,
47  // so the Stack Pointer Offset calculation of "not in
48  // register arguments" must be postponed to emitPrologue.
49  SmallVector<MipsFIHolder, 16> FnLoadArgs;
50  bool HasLoadArgs;
51
52  // When VarArgs, we must write registers back to caller
53  // stack, preserving on register arguments. Since the
54  // stack size is unknown on LowerFORMAL_ARGUMENTS,
55  // the Stack Pointer Offset calculation must be
56  // postponed to emitPrologue.
57  SmallVector<MipsFIHolder, 4> FnStoreVarArgs;
58  bool HasStoreVarArgs;
59
60public:
61  MipsFunctionInfo(MachineFunction& MF)
62  : FPStackOffset(0), RAStackOffset(0),
63    HasLoadArgs(false), HasStoreVarArgs(false)
64  {}
65
66  int getFPStackOffset() const { return FPStackOffset; }
67  void setFPStackOffset(int Off) { FPStackOffset = Off; }
68
69  int getRAStackOffset() const { return RAStackOffset; }
70  void setRAStackOffset(int Off) { RAStackOffset = Off; }
71
72  int getTopSavedRegOffset() const {
73    return (RAStackOffset > FPStackOffset) ?
74           (RAStackOffset) : (FPStackOffset);
75  }
76
77  bool hasLoadArgs() const { return HasLoadArgs; }
78  bool hasStoreVarArgs() const { return HasStoreVarArgs; }
79
80  void recordLoadArgsFI(int FI, int SPOffset) {
81    if (!HasLoadArgs) HasLoadArgs=true;
82    FnLoadArgs.push_back(MipsFIHolder(FI, SPOffset));
83  }
84  void recordStoreVarArgsFI(int FI, int SPOffset) {
85    if (!HasStoreVarArgs) HasStoreVarArgs=true;
86    FnStoreVarArgs.push_back(MipsFIHolder(FI, SPOffset));
87  }
88
89  void adjustLoadArgsFI(MachineFrameInfo *MFI) const {
90    if (!hasLoadArgs()) return;
91    for (unsigned i = 0, e = FnLoadArgs.size(); i != e; ++i)
92      MFI->setObjectOffset( FnLoadArgs[i].FI, FnLoadArgs[i].SPOffset );
93  }
94  void adjustStoreVarArgsFI(MachineFrameInfo *MFI) const {
95    if (!hasStoreVarArgs()) return;
96    for (unsigned i = 0, e = FnStoreVarArgs.size(); i != e; ++i)
97      MFI->setObjectOffset( FnStoreVarArgs[i].FI, FnStoreVarArgs[i].SPOffset );
98  }
99
100};
101
102} // end of namespace llvm
103
104#endif // MIPS_MACHINE_FUNCTION_INFO_H
105