1 //===-- X86MachineFunctionInfo.h - X86 machine function info ----*- 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 X86-specific per-machine-function information.
11 //
12 //===----------------------------------------------------------------------===//
13 
14 #ifndef LLVM_LIB_TARGET_X86_X86MACHINEFUNCTIONINFO_H
15 #define LLVM_LIB_TARGET_X86_X86MACHINEFUNCTIONINFO_H
16 
17 #include "llvm/CodeGen/CallingConvLower.h"
18 #include "llvm/CodeGen/MachineFunction.h"
19 #include "llvm/CodeGen/MachineValueType.h"
20 #include <vector>
21 
22 namespace llvm {
23 
24 /// X86MachineFunctionInfo - This class is derived from MachineFunction and
25 /// contains private X86 target-specific information for each MachineFunction.
26 class X86MachineFunctionInfo : public MachineFunctionInfo {
27   virtual void anchor();
28 
29   /// ForceFramePointer - True if the function is required to use of frame
30   /// pointer for reasons other than it containing dynamic allocation or
31   /// that FP eliminatation is turned off. For example, Cygwin main function
32   /// contains stack pointer re-alignment code which requires FP.
33   bool ForceFramePointer = false;
34 
35   /// RestoreBasePointerOffset - Non-zero if the function has base pointer
36   /// and makes call to llvm.eh.sjlj.setjmp. When non-zero, the value is a
37   /// displacement from the frame pointer to a slot where the base pointer
38   /// is stashed.
39   signed char RestoreBasePointerOffset = 0;
40 
41   /// CalleeSavedFrameSize - Size of the callee-saved register portion of the
42   /// stack frame in bytes.
43   unsigned CalleeSavedFrameSize = 0;
44 
45   /// BytesToPopOnReturn - Number of bytes function pops on return (in addition
46   /// to the space used by the return address).
47   /// Used on windows platform for stdcall & fastcall name decoration
48   unsigned BytesToPopOnReturn = 0;
49 
50   /// ReturnAddrIndex - FrameIndex for return slot.
51   int ReturnAddrIndex = 0;
52 
53   /// \brief FrameIndex for return slot.
54   int FrameAddrIndex = 0;
55 
56   /// TailCallReturnAddrDelta - The number of bytes by which return address
57   /// stack slot is moved as the result of tail call optimization.
58   int TailCallReturnAddrDelta = 0;
59 
60   /// SRetReturnReg - Some subtargets require that sret lowering includes
61   /// returning the value of the returned struct in a register. This field
62   /// holds the virtual register into which the sret argument is passed.
63   unsigned SRetReturnReg = 0;
64 
65   /// GlobalBaseReg - keeps track of the virtual register initialized for
66   /// use as the global base register. This is used for PIC in some PIC
67   /// relocation models.
68   unsigned GlobalBaseReg = 0;
69 
70   /// VarArgsFrameIndex - FrameIndex for start of varargs area.
71   int VarArgsFrameIndex = 0;
72   /// RegSaveFrameIndex - X86-64 vararg func register save area.
73   int RegSaveFrameIndex = 0;
74   /// VarArgsGPOffset - X86-64 vararg func int reg offset.
75   unsigned VarArgsGPOffset = 0;
76   /// VarArgsFPOffset - X86-64 vararg func fp reg offset.
77   unsigned VarArgsFPOffset = 0;
78   /// ArgumentStackSize - The number of bytes on stack consumed by the arguments
79   /// being passed on the stack.
80   unsigned ArgumentStackSize = 0;
81   /// NumLocalDynamics - Number of local-dynamic TLS accesses.
82   unsigned NumLocalDynamics = 0;
83   /// HasPushSequences - Keeps track of whether this function uses sequences
84   /// of pushes to pass function parameters.
85   bool HasPushSequences = false;
86 
87   /// True if the function recovers from an SEH exception, and therefore needs
88   /// to spill and restore the frame pointer.
89   bool HasSEHFramePtrSave = false;
90 
91   /// The frame index of a stack object containing the original frame pointer
92   /// used to address arguments in a function using a base pointer.
93   int SEHFramePtrSaveIndex = 0;
94 
95   /// True if this function has a subset of CSRs that is handled explicitly via
96   /// copies.
97   bool IsSplitCSR = false;
98 
99   /// True if this function uses the red zone.
100   bool UsesRedZone = false;
101 
102 private:
103   /// ForwardedMustTailRegParms - A list of virtual and physical registers
104   /// that must be forwarded to every musttail call.
105   SmallVector<ForwardedRegister, 1> ForwardedMustTailRegParms;
106 
107 public:
108   X86MachineFunctionInfo() = default;
109 
110   explicit X86MachineFunctionInfo(MachineFunction &MF) {}
111 
112   bool getForceFramePointer() const { return ForceFramePointer;}
113   void setForceFramePointer(bool forceFP) { ForceFramePointer = forceFP; }
114 
115   bool getHasPushSequences() const { return HasPushSequences; }
116   void setHasPushSequences(bool HasPush) { HasPushSequences = HasPush; }
117 
118   bool getRestoreBasePointer() const { return RestoreBasePointerOffset!=0; }
119   void setRestoreBasePointer(const MachineFunction *MF);
120   int getRestoreBasePointerOffset() const {return RestoreBasePointerOffset; }
121 
122   unsigned getCalleeSavedFrameSize() const { return CalleeSavedFrameSize; }
123   void setCalleeSavedFrameSize(unsigned bytes) { CalleeSavedFrameSize = bytes; }
124 
125   unsigned getBytesToPopOnReturn() const { return BytesToPopOnReturn; }
126   void setBytesToPopOnReturn (unsigned bytes) { BytesToPopOnReturn = bytes;}
127 
128   int getRAIndex() const { return ReturnAddrIndex; }
129   void setRAIndex(int Index) { ReturnAddrIndex = Index; }
130 
131   int getFAIndex() const { return FrameAddrIndex; }
132   void setFAIndex(int Index) { FrameAddrIndex = Index; }
133 
134   int getTCReturnAddrDelta() const { return TailCallReturnAddrDelta; }
135   void setTCReturnAddrDelta(int delta) {TailCallReturnAddrDelta = delta;}
136 
137   unsigned getSRetReturnReg() const { return SRetReturnReg; }
138   void setSRetReturnReg(unsigned Reg) { SRetReturnReg = Reg; }
139 
140   unsigned getGlobalBaseReg() const { return GlobalBaseReg; }
141   void setGlobalBaseReg(unsigned Reg) { GlobalBaseReg = Reg; }
142 
143   int getVarArgsFrameIndex() const { return VarArgsFrameIndex; }
144   void setVarArgsFrameIndex(int Idx) { VarArgsFrameIndex = Idx; }
145 
146   int getRegSaveFrameIndex() const { return RegSaveFrameIndex; }
147   void setRegSaveFrameIndex(int Idx) { RegSaveFrameIndex = Idx; }
148 
149   unsigned getVarArgsGPOffset() const { return VarArgsGPOffset; }
150   void setVarArgsGPOffset(unsigned Offset) { VarArgsGPOffset = Offset; }
151 
152   unsigned getVarArgsFPOffset() const { return VarArgsFPOffset; }
153   void setVarArgsFPOffset(unsigned Offset) { VarArgsFPOffset = Offset; }
154 
155   unsigned getArgumentStackSize() const { return ArgumentStackSize; }
156   void setArgumentStackSize(unsigned size) { ArgumentStackSize = size; }
157 
158   unsigned getNumLocalDynamicTLSAccesses() const { return NumLocalDynamics; }
159   void incNumLocalDynamicTLSAccesses() { ++NumLocalDynamics; }
160 
161   bool getHasSEHFramePtrSave() const { return HasSEHFramePtrSave; }
162   void setHasSEHFramePtrSave(bool V) { HasSEHFramePtrSave = V; }
163 
164   int getSEHFramePtrSaveIndex() const { return SEHFramePtrSaveIndex; }
165   void setSEHFramePtrSaveIndex(int Index) { SEHFramePtrSaveIndex = Index; }
166 
167   SmallVectorImpl<ForwardedRegister> &getForwardedMustTailRegParms() {
168     return ForwardedMustTailRegParms;
169   }
170 
171   bool isSplitCSR() const { return IsSplitCSR; }
172   void setIsSplitCSR(bool s) { IsSplitCSR = s; }
173 
174   bool getUsesRedZone() const { return UsesRedZone; }
175   void setUsesRedZone(bool V) { UsesRedZone = V; }
176 };
177 
178 } // End llvm namespace
179 
180 #endif
181