1 //===-- PPCMachineFunctionInfo.h - Private data used for PowerPC --*- 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 PowerPC specific subclass of MachineFunctionInfo.
11 //
12 //===----------------------------------------------------------------------===//
13 
14 #ifndef LLVM_LIB_TARGET_POWERPC_PPCMACHINEFUNCTIONINFO_H
15 #define LLVM_LIB_TARGET_POWERPC_PPCMACHINEFUNCTIONINFO_H
16 
17 #include "llvm/ADT/SmallVector.h"
18 #include "llvm/CodeGen/MachineFunction.h"
19 #include "llvm/CodeGen/TargetCallingConv.h"
20 
21 namespace llvm {
22 
23 /// PPCFunctionInfo - This class is derived from MachineFunction private
24 /// PowerPC target-specific information for each MachineFunction.
25 class PPCFunctionInfo : public MachineFunctionInfo {
26   virtual void anchor();
27 
28   /// FramePointerSaveIndex - Frame index of where the old frame pointer is
29   /// stored.  Also used as an anchor for instructions that need to be altered
30   /// when using frame pointers (dyna_add, dyna_sub.)
31   int FramePointerSaveIndex = 0;
32 
33   /// ReturnAddrSaveIndex - Frame index of where the return address is stored.
34   ///
35   int ReturnAddrSaveIndex = 0;
36 
37   /// Frame index where the old base pointer is stored.
38   int BasePointerSaveIndex = 0;
39 
40   /// Frame index where the old PIC base pointer is stored.
41   int PICBasePointerSaveIndex = 0;
42 
43   /// MustSaveLR - Indicates whether LR is defined (or clobbered) in the current
44   /// function.  This is only valid after the initial scan of the function by
45   /// PEI.
46   bool MustSaveLR;
47 
48   /// Does this function have any stack spills.
49   bool HasSpills = false;
50 
51   /// Does this function spill using instructions with only r+r (not r+i)
52   /// forms.
53   bool HasNonRISpills = false;
54 
55   /// SpillsCR - Indicates whether CR is spilled in the current function.
56   bool SpillsCR = false;
57 
58   /// Indicates whether VRSAVE is spilled in the current function.
59   bool SpillsVRSAVE = false;
60 
61   /// LRStoreRequired - The bool indicates whether there is some explicit use of
62   /// the LR/LR8 stack slot that is not obvious from scanning the code.  This
63   /// requires that the code generator produce a store of LR to the stack on
64   /// entry, even though LR may otherwise apparently not be used.
65   bool LRStoreRequired = false;
66 
67   /// This function makes use of the PPC64 ELF TOC base pointer (register r2).
68   bool UsesTOCBasePtr = false;
69 
70   /// MinReservedArea - This is the frame size that is at least reserved in a
71   /// potential caller (parameter+linkage area).
72   unsigned MinReservedArea = 0;
73 
74   /// TailCallSPDelta - Stack pointer delta used when tail calling. Maximum
75   /// amount the stack pointer is adjusted to make the frame bigger for tail
76   /// calls. Used for creating an area before the register spill area.
77   int TailCallSPDelta = 0;
78 
79   /// HasFastCall - Does this function contain a fast call. Used to determine
80   /// how the caller's stack pointer should be calculated (epilog/dynamicalloc).
81   bool HasFastCall = false;
82 
83   /// VarArgsFrameIndex - FrameIndex for start of varargs area.
84   int VarArgsFrameIndex = 0;
85 
86   /// VarArgsStackOffset - StackOffset for start of stack
87   /// arguments.
88 
89   int VarArgsStackOffset = 0;
90 
91   /// VarArgsNumGPR - Index of the first unused integer
92   /// register for parameter passing.
93   unsigned VarArgsNumGPR = 0;
94 
95   /// VarArgsNumFPR - Index of the first unused double
96   /// register for parameter passing.
97   unsigned VarArgsNumFPR = 0;
98 
99   /// CRSpillFrameIndex - FrameIndex for CR spill slot for 32-bit SVR4.
100   int CRSpillFrameIndex = 0;
101 
102   /// If any of CR[2-4] need to be saved in the prologue and restored in the
103   /// epilogue then they are added to this array. This is used for the
104   /// 64-bit SVR4 ABI.
105   SmallVector<unsigned, 3> MustSaveCRs;
106 
107   /// Hold onto our MachineFunction context.
108   MachineFunction &MF;
109 
110   /// Whether this uses the PIC Base register or not.
111   bool UsesPICBase = false;
112 
113   /// True if this function has a subset of CSRs that is handled explicitly via
114   /// copies
115   bool IsSplitCSR = false;
116 
117   /// We keep track attributes for each live-in virtual registers
118   /// to use SExt/ZExt flags in later optimization.
119   std::vector<std::pair<unsigned, ISD::ArgFlagsTy>> LiveInAttrs;
120 
121 public:
122   explicit PPCFunctionInfo(MachineFunction &MF) : MF(MF) {}
123 
124   int getFramePointerSaveIndex() const { return FramePointerSaveIndex; }
125   void setFramePointerSaveIndex(int Idx) { FramePointerSaveIndex = Idx; }
126 
127   int getReturnAddrSaveIndex() const { return ReturnAddrSaveIndex; }
128   void setReturnAddrSaveIndex(int idx) { ReturnAddrSaveIndex = idx; }
129 
130   int getBasePointerSaveIndex() const { return BasePointerSaveIndex; }
131   void setBasePointerSaveIndex(int Idx) { BasePointerSaveIndex = Idx; }
132 
133   int getPICBasePointerSaveIndex() const { return PICBasePointerSaveIndex; }
134   void setPICBasePointerSaveIndex(int Idx) { PICBasePointerSaveIndex = Idx; }
135 
136   unsigned getMinReservedArea() const { return MinReservedArea; }
137   void setMinReservedArea(unsigned size) { MinReservedArea = size; }
138 
139   int getTailCallSPDelta() const { return TailCallSPDelta; }
140   void setTailCallSPDelta(int size) { TailCallSPDelta = size; }
141 
142   /// MustSaveLR - This is set when the prolog/epilog inserter does its initial
143   /// scan of the function. It is true if the LR/LR8 register is ever explicitly
144   /// defined/clobbered in the machine function (e.g. by calls and movpctolr,
145   /// which is used in PIC generation), or if the LR stack slot is explicitly
146   /// referenced by builtin_return_address.
147   void setMustSaveLR(bool U) { MustSaveLR = U; }
148   bool mustSaveLR() const    { return MustSaveLR; }
149 
150   void setHasSpills()      { HasSpills = true; }
151   bool hasSpills() const   { return HasSpills; }
152 
153   void setHasNonRISpills()    { HasNonRISpills = true; }
154   bool hasNonRISpills() const { return HasNonRISpills; }
155 
156   void setSpillsCR()       { SpillsCR = true; }
157   bool isCRSpilled() const { return SpillsCR; }
158 
159   void setSpillsVRSAVE()       { SpillsVRSAVE = true; }
160   bool isVRSAVESpilled() const { return SpillsVRSAVE; }
161 
162   void setLRStoreRequired() { LRStoreRequired = true; }
163   bool isLRStoreRequired() const { return LRStoreRequired; }
164 
165   void setUsesTOCBasePtr()    { UsesTOCBasePtr = true; }
166   bool usesTOCBasePtr() const { return UsesTOCBasePtr; }
167 
168   void setHasFastCall() { HasFastCall = true; }
169   bool hasFastCall() const { return HasFastCall;}
170 
171   int getVarArgsFrameIndex() const { return VarArgsFrameIndex; }
172   void setVarArgsFrameIndex(int Index) { VarArgsFrameIndex = Index; }
173 
174   int getVarArgsStackOffset() const { return VarArgsStackOffset; }
175   void setVarArgsStackOffset(int Offset) { VarArgsStackOffset = Offset; }
176 
177   unsigned getVarArgsNumGPR() const { return VarArgsNumGPR; }
178   void setVarArgsNumGPR(unsigned Num) { VarArgsNumGPR = Num; }
179 
180   unsigned getVarArgsNumFPR() const { return VarArgsNumFPR; }
181   void setVarArgsNumFPR(unsigned Num) { VarArgsNumFPR = Num; }
182 
183   /// This function associates attributes for each live-in virtual register.
184   void addLiveInAttr(unsigned VReg, ISD::ArgFlagsTy Flags) {
185     LiveInAttrs.push_back(std::make_pair(VReg, Flags));
186   }
187 
188   /// This function returns true if the spesified vreg is
189   /// a live-in register and sign-extended.
190   bool isLiveInSExt(unsigned VReg) const;
191 
192   /// This function returns true if the spesified vreg is
193   /// a live-in register and zero-extended.
194   bool isLiveInZExt(unsigned VReg) const;
195 
196   int getCRSpillFrameIndex() const { return CRSpillFrameIndex; }
197   void setCRSpillFrameIndex(int idx) { CRSpillFrameIndex = idx; }
198 
199   const SmallVectorImpl<unsigned> &
200     getMustSaveCRs() const { return MustSaveCRs; }
201   void addMustSaveCR(unsigned Reg) { MustSaveCRs.push_back(Reg); }
202 
203   void setUsesPICBase(bool uses) { UsesPICBase = uses; }
204   bool usesPICBase() const { return UsesPICBase; }
205 
206   bool isSplitCSR() const { return IsSplitCSR; }
207   void setIsSplitCSR(bool s) { IsSplitCSR = s; }
208 
209   MCSymbol *getPICOffsetSymbol() const;
210 
211   MCSymbol *getGlobalEPSymbol() const;
212   MCSymbol *getLocalEPSymbol() const;
213   MCSymbol *getTOCOffsetSymbol() const;
214 };
215 
216 } // end namespace llvm
217 
218 #endif // LLVM_LIB_TARGET_POWERPC_PPCMACHINEFUNCTIONINFO_H
219