1 //===-- FunctionLoweringInfo.h - Lower functions from LLVM IR to CodeGen --===//
3 // The LLVM Compiler Infrastructure
5 // This file is distributed under the University of Illinois Open Source
6 // License. See LICENSE.TXT for details.
8 //===----------------------------------------------------------------------===//
10 // This implements routines for translating functions from LLVM IR into
13 //===----------------------------------------------------------------------===//
15 #ifndef LLVM_CODEGEN_FUNCTIONLOWERINGINFO_H
16 #define LLVM_CODEGEN_FUNCTIONLOWERINGINFO_H
18 #include "llvm/InlineAsm.h"
19 #include "llvm/Instructions.h"
20 #include "llvm/ADT/APInt.h"
21 #include "llvm/ADT/DenseMap.h"
22 #include "llvm/ADT/IndexedMap.h"
23 #include "llvm/ADT/SmallVector.h"
25 #include "llvm/ADT/SmallSet.h"
27 #include "llvm/CodeGen/ValueTypes.h"
28 #include "llvm/CodeGen/ISDOpcodes.h"
29 #include "llvm/CodeGen/MachineBasicBlock.h"
30 #include "llvm/Support/CallSite.h"
31 #include "llvm/Target/TargetRegisterInfo.h"
43 class MachineBasicBlock;
44 class MachineFunction;
45 class MachineModuleInfo;
46 class MachineRegisterInfo;
50 //===--------------------------------------------------------------------===//
51 /// FunctionLoweringInfo - This contains information that is global to a
52 /// function that is used when lowering a region of the function.
54 class FunctionLoweringInfo {
56 const TargetLowering &TLI;
59 MachineRegisterInfo *RegInfo;
61 /// CanLowerReturn - true iff the function's return value can be lowered to
65 /// DemoteRegister - if CanLowerReturn is false, DemoteRegister is a vreg
66 /// allocated to hold a pointer to the hidden sret parameter.
67 unsigned DemoteRegister;
69 /// MBBMap - A mapping from LLVM basic blocks to their machine code entry.
70 DenseMap<const BasicBlock*, MachineBasicBlock *> MBBMap;
72 /// ValueMap - Since we emit code for the function a basic block at a time,
73 /// we must remember which virtual registers hold the values for
74 /// cross-basic-block values.
75 DenseMap<const Value*, unsigned> ValueMap;
77 /// StaticAllocaMap - Keep track of frame indices for fixed sized allocas in
78 /// the entry block. This allows the allocas to be efficiently referenced
79 /// anywhere in the function.
80 DenseMap<const AllocaInst*, int> StaticAllocaMap;
82 /// ByValArgFrameIndexMap - Keep track of frame indices for byval arguments.
83 DenseMap<const Argument*, int> ByValArgFrameIndexMap;
85 /// ArgDbgValues - A list of DBG_VALUE instructions created during isel for
86 /// function arguments that are inserted after scheduling is completed.
87 SmallVector<MachineInstr*, 8> ArgDbgValues;
89 /// RegFixups - Registers which need to be replaced after isel is done.
90 DenseMap<unsigned, unsigned> RegFixups;
92 /// MBB - The current block.
93 MachineBasicBlock *MBB;
95 /// MBB - The current insert position inside the current block.
96 MachineBasicBlock::iterator InsertPt;
99 SmallSet<const Instruction *, 8> CatchInfoLost;
100 SmallSet<const Instruction *, 8> CatchInfoFound;
104 unsigned NumSignBits;
105 APInt KnownOne, KnownZero;
106 LiveOutInfo() : NumSignBits(0), KnownOne(1, 0), KnownZero(1, 0) {}
109 /// VisitedBBs - The set of basic blocks visited thus far by instruction
111 DenseSet<const BasicBlock*> VisitedBBs;
113 /// PHINodesToUpdate - A list of phi instructions whose operand list will
114 /// be updated after processing the current basic block.
115 /// TODO: This isn't per-function state, it's per-basic-block state. But
116 /// there's no other convenient place for it to live right now.
117 std::vector<std::pair<MachineInstr*, unsigned> > PHINodesToUpdate;
119 explicit FunctionLoweringInfo(const TargetLowering &TLI);
121 /// set - Initialize this FunctionLoweringInfo with the given Function
122 /// and its associated MachineFunction.
124 void set(const Function &Fn, MachineFunction &MF);
126 /// clear - Clear out all the function-specific state. This returns this
127 /// FunctionLoweringInfo to an empty state, ready to be used for a
128 /// different function.
131 /// isExportedInst - Return true if the specified value is an instruction
132 /// exported from its block.
133 bool isExportedInst(const Value *V) {
134 return ValueMap.count(V);
137 unsigned CreateReg(EVT VT);
139 unsigned CreateRegs(const Type *Ty);
141 unsigned InitializeRegForValue(const Value *V) {
142 unsigned &R = ValueMap[V];
143 assert(R == 0 && "Already initialized this value register!");
144 return R = CreateRegs(V->getType());
147 /// GetLiveOutRegInfo - Gets LiveOutInfo for a register, returning NULL if the
148 /// register is a PHI destination and the PHI's LiveOutInfo is not valid.
149 const LiveOutInfo *GetLiveOutRegInfo(unsigned Reg) {
150 if (!LiveOutRegInfo.inBounds(Reg))
152 return &LiveOutRegInfo[Reg];
155 /// AddLiveOutRegInfo - Adds LiveOutInfo for a register.
156 void AddLiveOutRegInfo(unsigned Reg, unsigned NumSignBits,
157 const APInt &KnownZero, const APInt &KnownOne) {
158 // Only install this information if it tells us something.
159 if (NumSignBits == 1 && KnownZero == 0 && KnownOne == 0)
162 LiveOutRegInfo.grow(Reg);
163 LiveOutInfo &LOI = LiveOutRegInfo[Reg];
164 LOI.NumSignBits = NumSignBits;
165 LOI.KnownOne = KnownOne;
166 LOI.KnownZero = KnownZero;
169 /// setByValArgumentFrameIndex - Record frame index for the byval
171 void setByValArgumentFrameIndex(const Argument *A, int FI);
173 /// getByValArgumentFrameIndex - Get frame index for the byval argument.
174 int getByValArgumentFrameIndex(const Argument *A);
177 /// LiveOutRegInfo - Information about live out vregs.
178 IndexedMap<LiveOutInfo, VirtReg2IndexFunctor> LiveOutRegInfo;
181 /// AddCatchInfo - Extract the personality and type infos from an eh.selector
182 /// call, and add them to the specified machine basic block.
183 void AddCatchInfo(const CallInst &I,
184 MachineModuleInfo *MMI, MachineBasicBlock *MBB);
186 /// CopyCatchInfo - Copy catch information from DestBB to SrcBB.
187 void CopyCatchInfo(const BasicBlock *SrcBB, const BasicBlock *DestBB,
188 MachineModuleInfo *MMI, FunctionLoweringInfo &FLI);
190 } // end namespace llvm