xref: /freebsd/contrib/llvm-project/llvm/lib/Target/X86/X86MachineFunctionInfo.h (revision 357378bbdedf24ce2b90e9bd831af4a9db3ec70a) 
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/ADT/ArrayRef.h"
17 #include "llvm/ADT/SmallVector.h"
18 #include "llvm/CodeGen/CallingConvLower.h"
19 #include "llvm/CodeGen/MachineFunction.h"
20 #include <set>
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   /// WinEHXMMSlotInfo - Slot information of XMM registers in the stack frame
42   /// in bytes.
43   DenseMap<int, unsigned> WinEHXMMSlotInfo;
44 
45   /// CalleeSavedFrameSize - Size of the callee-saved register portion of the
46   /// stack frame in bytes.
47   unsigned CalleeSavedFrameSize = 0;
48 
49   /// BytesToPopOnReturn - Number of bytes function pops on return (in addition
50   /// to the space used by the return address).
51   /// Used on windows platform for stdcall & fastcall name decoration
52   unsigned BytesToPopOnReturn = 0;
53 
54   /// ReturnAddrIndex - FrameIndex for return slot.
55   int ReturnAddrIndex = 0;
56 
57   /// FrameIndex for return slot.
58   int FrameAddrIndex = 0;
59 
60   /// TailCallReturnAddrDelta - The number of bytes by which return address
61   /// stack slot is moved as the result of tail call optimization.
62   int TailCallReturnAddrDelta = 0;
63 
64   /// SRetReturnReg - Some subtargets require that sret lowering includes
65   /// returning the value of the returned struct in a register. This field
66   /// holds the virtual register into which the sret argument is passed.
67   Register SRetReturnReg;
68 
69   /// GlobalBaseReg - keeps track of the virtual register initialized for
70   /// use as the global base register. This is used for PIC in some PIC
71   /// relocation models.
72   Register GlobalBaseReg;
73 
74   /// VarArgsFrameIndex - FrameIndex for start of varargs area.
75   int VarArgsFrameIndex = 0;
76   /// RegSaveFrameIndex - X86-64 vararg func register save area.
77   int RegSaveFrameIndex = 0;
78   /// VarArgsGPOffset - X86-64 vararg func int reg offset.
79   unsigned VarArgsGPOffset = 0;
80   /// VarArgsFPOffset - X86-64 vararg func fp reg offset.
81   unsigned VarArgsFPOffset = 0;
82   /// ArgumentStackSize - The number of bytes on stack consumed by the arguments
83   /// being passed on the stack.
84   unsigned ArgumentStackSize = 0;
85   /// NumLocalDynamics - Number of local-dynamic TLS accesses.
86   unsigned NumLocalDynamics = 0;
87   /// HasPushSequences - Keeps track of whether this function uses sequences
88   /// of pushes to pass function parameters.
89   bool HasPushSequences = false;
90 
91   /// True if the function recovers from an SEH exception, and therefore needs
92   /// to spill and restore the frame pointer.
93   bool HasSEHFramePtrSave = false;
94 
95   /// The frame index of a stack object containing the original frame pointer
96   /// used to address arguments in a function using a base pointer.
97   int SEHFramePtrSaveIndex = 0;
98 
99   /// True if this function has a subset of CSRs that is handled explicitly via
100   /// copies.
101   bool IsSplitCSR = false;
102 
103   /// True if this function uses the red zone.
104   bool UsesRedZone = false;
105 
106   /// True if this function has DYN_ALLOCA instructions.
107   bool HasDynAlloca = false;
108 
109   /// True if this function has any preallocated calls.
110   bool HasPreallocatedCall = false;
111 
112   /// Whether this function has an extended frame record [Ctx, RBP, Return
113   /// addr]. If so, bit 60 of the in-memory frame pointer will be 1 to enable
114   /// other tools to detect the extended record.
115   bool HasSwiftAsyncContext = false;
116 
117   /// True if this function has tile virtual register. This is used to
118   /// determine if we should insert tilerelease in frame lowering.
119   bool HasVirtualTileReg = false;
120 
121   /// Ajust stack for push2/pop2
122   bool PadForPush2Pop2 = false;
123 
124   /// Candidate registers for push2/pop2
125   std::set<Register> CandidatesForPush2Pop2;
126 
127   /// True if this function has CFI directives that adjust the CFA.
128   /// This is used to determine if we should direct the debugger to use
129   /// the CFA instead of the stack pointer.
130   bool HasCFIAdjustCfa = false;
131 
132   MachineInstr *StackPtrSaveMI = nullptr;
133 
134   std::optional<int> SwiftAsyncContextFrameIdx;
135 
136   // Preallocated fields are only used during isel.
137   // FIXME: Can we find somewhere else to store these?
138   DenseMap<const Value *, size_t> PreallocatedIds;
139   SmallVector<size_t, 0> PreallocatedStackSizes;
140   SmallVector<SmallVector<size_t, 4>, 0> PreallocatedArgOffsets;
141 
142 private:
143   /// ForwardedMustTailRegParms - A list of virtual and physical registers
144   /// that must be forwarded to every musttail call.
145   SmallVector<ForwardedRegister, 1> ForwardedMustTailRegParms;
146 
147 public:
148   X86MachineFunctionInfo() = default;
149   X86MachineFunctionInfo(const Function &F, const TargetSubtargetInfo *STI) {}
150 
151   X86MachineFunctionInfo(const X86MachineFunctionInfo &) = default;
152 
153   MachineFunctionInfo *
154   clone(BumpPtrAllocator &Allocator, MachineFunction &DestMF,
155         const DenseMap<MachineBasicBlock *, MachineBasicBlock *> &Src2DstMBB)
156       const override;
157 
158   bool getForceFramePointer() const { return ForceFramePointer;}
159   void setForceFramePointer(bool forceFP) { ForceFramePointer = forceFP; }
160 
161   bool getHasPushSequences() const { return HasPushSequences; }
162   void setHasPushSequences(bool HasPush) { HasPushSequences = HasPush; }
163 
164   bool getRestoreBasePointer() const { return RestoreBasePointerOffset!=0; }
165   void setRestoreBasePointer(const MachineFunction *MF);
166   void setRestoreBasePointer(unsigned CalleeSavedFrameSize) {
167     RestoreBasePointerOffset = -CalleeSavedFrameSize;
168   }
169   int getRestoreBasePointerOffset() const {return RestoreBasePointerOffset; }
170 
171   DenseMap<int, unsigned>& getWinEHXMMSlotInfo() { return WinEHXMMSlotInfo; }
172   const DenseMap<int, unsigned>& getWinEHXMMSlotInfo() const {
173     return WinEHXMMSlotInfo; }
174 
175   unsigned getCalleeSavedFrameSize() const {
176     return CalleeSavedFrameSize + 8 * padForPush2Pop2();
177   }
178   void setCalleeSavedFrameSize(unsigned bytes) { CalleeSavedFrameSize = bytes; }
179 
180   unsigned getBytesToPopOnReturn() const { return BytesToPopOnReturn; }
181   void setBytesToPopOnReturn (unsigned bytes) { BytesToPopOnReturn = bytes;}
182 
183   int getRAIndex() const { return ReturnAddrIndex; }
184   void setRAIndex(int Index) { ReturnAddrIndex = Index; }
185 
186   int getFAIndex() const { return FrameAddrIndex; }
187   void setFAIndex(int Index) { FrameAddrIndex = Index; }
188 
189   int getTCReturnAddrDelta() const { return TailCallReturnAddrDelta; }
190   void setTCReturnAddrDelta(int delta) {TailCallReturnAddrDelta = delta;}
191 
192   Register getSRetReturnReg() const { return SRetReturnReg; }
193   void setSRetReturnReg(Register Reg) { SRetReturnReg = Reg; }
194 
195   Register getGlobalBaseReg() const { return GlobalBaseReg; }
196   void setGlobalBaseReg(Register Reg) { GlobalBaseReg = Reg; }
197 
198   int getVarArgsFrameIndex() const { return VarArgsFrameIndex; }
199   void setVarArgsFrameIndex(int Idx) { VarArgsFrameIndex = Idx; }
200 
201   int getRegSaveFrameIndex() const { return RegSaveFrameIndex; }
202   void setRegSaveFrameIndex(int Idx) { RegSaveFrameIndex = Idx; }
203 
204   unsigned getVarArgsGPOffset() const { return VarArgsGPOffset; }
205   void setVarArgsGPOffset(unsigned Offset) { VarArgsGPOffset = Offset; }
206 
207   unsigned getVarArgsFPOffset() const { return VarArgsFPOffset; }
208   void setVarArgsFPOffset(unsigned Offset) { VarArgsFPOffset = Offset; }
209 
210   unsigned getArgumentStackSize() const { return ArgumentStackSize; }
211   void setArgumentStackSize(unsigned size) { ArgumentStackSize = size; }
212 
213   unsigned getNumLocalDynamicTLSAccesses() const { return NumLocalDynamics; }
214   void incNumLocalDynamicTLSAccesses() { ++NumLocalDynamics; }
215 
216   bool getHasSEHFramePtrSave() const { return HasSEHFramePtrSave; }
217   void setHasSEHFramePtrSave(bool V) { HasSEHFramePtrSave = V; }
218 
219   int getSEHFramePtrSaveIndex() const { return SEHFramePtrSaveIndex; }
220   void setSEHFramePtrSaveIndex(int Index) { SEHFramePtrSaveIndex = Index; }
221 
222   SmallVectorImpl<ForwardedRegister> &getForwardedMustTailRegParms() {
223     return ForwardedMustTailRegParms;
224   }
225 
226   bool isSplitCSR() const { return IsSplitCSR; }
227   void setIsSplitCSR(bool s) { IsSplitCSR = s; }
228 
229   bool getUsesRedZone() const { return UsesRedZone; }
230   void setUsesRedZone(bool V) { UsesRedZone = V; }
231 
232   bool hasDynAlloca() const { return HasDynAlloca; }
233   void setHasDynAlloca(bool v) { HasDynAlloca = v; }
234 
235   bool hasPreallocatedCall() const { return HasPreallocatedCall; }
236   void setHasPreallocatedCall(bool v) { HasPreallocatedCall = v; }
237 
238   bool hasSwiftAsyncContext() const { return HasSwiftAsyncContext; }
239   void setHasSwiftAsyncContext(bool v) { HasSwiftAsyncContext = v; }
240 
241   bool hasVirtualTileReg() const { return HasVirtualTileReg; }
242   void setHasVirtualTileReg(bool v) { HasVirtualTileReg = v; }
243 
244   bool padForPush2Pop2() const { return PadForPush2Pop2; }
245   void setPadForPush2Pop2(bool V) { PadForPush2Pop2 = V; }
246 
247   bool isCandidateForPush2Pop2(Register Reg) const {
248     return CandidatesForPush2Pop2.find(Reg) != CandidatesForPush2Pop2.end();
249   }
250   void addCandidateForPush2Pop2(Register Reg) {
251     CandidatesForPush2Pop2.insert(Reg);
252   }
253   size_t getNumCandidatesForPush2Pop2() const {
254     return CandidatesForPush2Pop2.size();
255   }
256 
257   bool hasCFIAdjustCfa() const { return HasCFIAdjustCfa; }
258   void setHasCFIAdjustCfa(bool v) { HasCFIAdjustCfa = v; }
259 
260   void setStackPtrSaveMI(MachineInstr *MI) { StackPtrSaveMI = MI; }
261   MachineInstr *getStackPtrSaveMI() const { return StackPtrSaveMI; }
262 
263   std::optional<int> getSwiftAsyncContextFrameIdx() const {
264     return SwiftAsyncContextFrameIdx;
265   }
266   void setSwiftAsyncContextFrameIdx(int v) { SwiftAsyncContextFrameIdx = v; }
267 
268   size_t getPreallocatedIdForCallSite(const Value *CS) {
269     auto Insert = PreallocatedIds.insert({CS, PreallocatedIds.size()});
270     if (Insert.second) {
271       PreallocatedStackSizes.push_back(0);
272       PreallocatedArgOffsets.emplace_back();
273     }
274     return Insert.first->second;
275   }
276 
277   void setPreallocatedStackSize(size_t Id, size_t StackSize) {
278     PreallocatedStackSizes[Id] = StackSize;
279   }
280 
281   size_t getPreallocatedStackSize(const size_t Id) {
282     assert(PreallocatedStackSizes[Id] != 0 && "stack size not set");
283     return PreallocatedStackSizes[Id];
284   }
285 
286   void setPreallocatedArgOffsets(size_t Id, ArrayRef<size_t> AO) {
287     PreallocatedArgOffsets[Id].assign(AO.begin(), AO.end());
288   }
289 
290   ArrayRef<size_t> getPreallocatedArgOffsets(const size_t Id) {
291     assert(!PreallocatedArgOffsets[Id].empty() && "arg offsets not set");
292     return PreallocatedArgOffsets[Id];
293   }
294 };
295 
296 } // End llvm namespace
297 
298 #endif
299