lib/Target/MBlaze/MBlazeMachineFunction.h

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