1 //===-- X86MachineFunctionInfo.h - X86 machine function info ----*- C++ -*-===//
2 //
3 // Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
4 // See https://llvm.org/LICENSE.txt for license information.
5 // SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
6 //
7 //===----------------------------------------------------------------------===//
8 //
9 // This file declares X86-specific per-machine-function information.
10 //
11 //===----------------------------------------------------------------------===//
12 
13 #ifndef LLVM_LIB_TARGET_X86_X86MACHINEFUNCTIONINFO_H
14 #define LLVM_LIB_TARGET_X86_X86MACHINEFUNCTIONINFO_H
15 
16 #include "llvm/CodeGen/CallingConvLower.h"
17 #include "llvm/CodeGen/MachineFunction.h"
18 #include "llvm/Support/MachineValueType.h"
19 
20 namespace llvm {
21 
22 /// X86MachineFunctionInfo - This class is derived from MachineFunction and
23 /// contains private X86 target-specific information for each MachineFunction.
24 class X86MachineFunctionInfo : public MachineFunctionInfo {
25   virtual void anchor();
26 
27   /// ForceFramePointer - True if the function is required to use of frame
28   /// pointer for reasons other than it containing dynamic allocation or
29   /// that FP eliminatation is turned off. For example, Cygwin main function
30   /// contains stack pointer re-alignment code which requires FP.
31   bool ForceFramePointer = false;
32 
33   /// RestoreBasePointerOffset - Non-zero if the function has base pointer
34   /// and makes call to llvm.eh.sjlj.setjmp. When non-zero, the value is a
35   /// displacement from the frame pointer to a slot where the base pointer
36   /// is stashed.
37   signed char RestoreBasePointerOffset = 0;
38 
39   /// WinEHXMMSlotInfo - Slot information of XMM registers in the stack frame
40   /// in bytes.
41   DenseMap<int, unsigned> WinEHXMMSlotInfo;
42 
43   /// CalleeSavedFrameSize - Size of the callee-saved register portion of the
44   /// stack frame in bytes.
45   unsigned CalleeSavedFrameSize = 0;
46 
47   /// BytesToPopOnReturn - Number of bytes function pops on return (in addition
48   /// to the space used by the return address).
49   /// Used on windows platform for stdcall & fastcall name decoration
50   unsigned BytesToPopOnReturn = 0;
51 
52   /// ReturnAddrIndex - FrameIndex for return slot.
53   int ReturnAddrIndex = 0;
54 
55   /// FrameIndex for return slot.
56   int FrameAddrIndex = 0;
57 
58   /// TailCallReturnAddrDelta - The number of bytes by which return address
59   /// stack slot is moved as the result of tail call optimization.
60   int TailCallReturnAddrDelta = 0;
61 
62   /// SRetReturnReg - Some subtargets require that sret lowering includes
63   /// returning the value of the returned struct in a register. This field
64   /// holds the virtual register into which the sret argument is passed.
65   unsigned SRetReturnReg = 0;
66 
67   /// GlobalBaseReg - keeps track of the virtual register initialized for
68   /// use as the global base register. This is used for PIC in some PIC
69   /// relocation models.
70   unsigned GlobalBaseReg = 0;
71 
72   /// VarArgsFrameIndex - FrameIndex for start of varargs area.
73   int VarArgsFrameIndex = 0;
74   /// RegSaveFrameIndex - X86-64 vararg func register save area.
75   int RegSaveFrameIndex = 0;
76   /// VarArgsGPOffset - X86-64 vararg func int reg offset.
77   unsigned VarArgsGPOffset = 0;
78   /// VarArgsFPOffset - X86-64 vararg func fp reg offset.
79   unsigned VarArgsFPOffset = 0;
80   /// ArgumentStackSize - The number of bytes on stack consumed by the arguments
81   /// being passed on the stack.
82   unsigned ArgumentStackSize = 0;
83   /// NumLocalDynamics - Number of local-dynamic TLS accesses.
84   unsigned NumLocalDynamics = 0;
85   /// HasPushSequences - Keeps track of whether this function uses sequences
86   /// of pushes to pass function parameters.
87   bool HasPushSequences = false;
88 
89   /// True if the function recovers from an SEH exception, and therefore needs
90   /// to spill and restore the frame pointer.
91   bool HasSEHFramePtrSave = false;
92 
93   /// The frame index of a stack object containing the original frame pointer
94   /// used to address arguments in a function using a base pointer.
95   int SEHFramePtrSaveIndex = 0;
96 
97   /// True if this function has a subset of CSRs that is handled explicitly via
98   /// copies.
99   bool IsSplitCSR = false;
100 
101   /// True if this function uses the red zone.
102   bool UsesRedZone = false;
103 
104   /// True if this function has WIN_ALLOCA instructions.
105   bool HasWinAlloca = false;
106 
107 private:
108   /// ForwardedMustTailRegParms - A list of virtual and physical registers
109   /// that must be forwarded to every musttail call.
110   SmallVector<ForwardedRegister, 1> ForwardedMustTailRegParms;
111 
112 public:
113   X86MachineFunctionInfo() = default;
114 
115   explicit X86MachineFunctionInfo(MachineFunction &MF) {}
116 
117   bool getForceFramePointer() const { return ForceFramePointer;}
118   void setForceFramePointer(bool forceFP) { ForceFramePointer = forceFP; }
119 
120   bool getHasPushSequences() const { return HasPushSequences; }
121   void setHasPushSequences(bool HasPush) { HasPushSequences = HasPush; }
122 
123   bool getRestoreBasePointer() const { return RestoreBasePointerOffset!=0; }
124   void setRestoreBasePointer(const MachineFunction *MF);
125   int getRestoreBasePointerOffset() const {return RestoreBasePointerOffset; }
126 
127   DenseMap<int, unsigned>& getWinEHXMMSlotInfo() { return WinEHXMMSlotInfo; }
128   const DenseMap<int, unsigned>& getWinEHXMMSlotInfo() const {
129     return WinEHXMMSlotInfo; }
130 
131   unsigned getCalleeSavedFrameSize() const { return CalleeSavedFrameSize; }
132   void setCalleeSavedFrameSize(unsigned bytes) { CalleeSavedFrameSize = bytes; }
133 
134   unsigned getBytesToPopOnReturn() const { return BytesToPopOnReturn; }
135   void setBytesToPopOnReturn (unsigned bytes) { BytesToPopOnReturn = bytes;}
136 
137   int getRAIndex() const { return ReturnAddrIndex; }
138   void setRAIndex(int Index) { ReturnAddrIndex = Index; }
139 
140   int getFAIndex() const { return FrameAddrIndex; }
141   void setFAIndex(int Index) { FrameAddrIndex = Index; }
142 
143   int getTCReturnAddrDelta() const { return TailCallReturnAddrDelta; }
144   void setTCReturnAddrDelta(int delta) {TailCallReturnAddrDelta = delta;}
145 
146   unsigned getSRetReturnReg() const { return SRetReturnReg; }
147   void setSRetReturnReg(unsigned Reg) { SRetReturnReg = Reg; }
148 
149   unsigned getGlobalBaseReg() const { return GlobalBaseReg; }
150   void setGlobalBaseReg(unsigned Reg) { GlobalBaseReg = Reg; }
151 
152   int getVarArgsFrameIndex() const { return VarArgsFrameIndex; }
153   void setVarArgsFrameIndex(int Idx) { VarArgsFrameIndex = Idx; }
154 
155   int getRegSaveFrameIndex() const { return RegSaveFrameIndex; }
156   void setRegSaveFrameIndex(int Idx) { RegSaveFrameIndex = Idx; }
157 
158   unsigned getVarArgsGPOffset() const { return VarArgsGPOffset; }
159   void setVarArgsGPOffset(unsigned Offset) { VarArgsGPOffset = Offset; }
160 
161   unsigned getVarArgsFPOffset() const { return VarArgsFPOffset; }
162   void setVarArgsFPOffset(unsigned Offset) { VarArgsFPOffset = Offset; }
163 
164   unsigned getArgumentStackSize() const { return ArgumentStackSize; }
165   void setArgumentStackSize(unsigned size) { ArgumentStackSize = size; }
166 
167   unsigned getNumLocalDynamicTLSAccesses() const { return NumLocalDynamics; }
168   void incNumLocalDynamicTLSAccesses() { ++NumLocalDynamics; }
169 
170   bool getHasSEHFramePtrSave() const { return HasSEHFramePtrSave; }
171   void setHasSEHFramePtrSave(bool V) { HasSEHFramePtrSave = V; }
172 
173   int getSEHFramePtrSaveIndex() const { return SEHFramePtrSaveIndex; }
174   void setSEHFramePtrSaveIndex(int Index) { SEHFramePtrSaveIndex = Index; }
175 
176   SmallVectorImpl<ForwardedRegister> &getForwardedMustTailRegParms() {
177     return ForwardedMustTailRegParms;
178   }
179 
180   bool isSplitCSR() const { return IsSplitCSR; }
181   void setIsSplitCSR(bool s) { IsSplitCSR = s; }
182 
183   bool getUsesRedZone() const { return UsesRedZone; }
184   void setUsesRedZone(bool V) { UsesRedZone = V; }
185 
186   bool hasWinAlloca() const { return HasWinAlloca; }
187   void setHasWinAlloca(bool v) { HasWinAlloca = v; }
188 };
189 
190 } // End llvm namespace
191 
192 #endif
193