1 //===-- llvm/CodeGen/SelectionDAGISel.h - Common Base Class------*- C++ -*-===//
3 // The LLVM Compiler Infrastructure
5 // This file was developed by the LLVM research group and is distributed under
6 // the University of Illinois Open Source License. See LICENSE.TXT for details.
8 //===----------------------------------------------------------------------===//
10 // This file implements the SelectionDAGISel class, which is used as the common
11 // base class for SelectionDAG-based instruction selectors.
13 //===----------------------------------------------------------------------===//
15 #ifndef LLVM_CODEGEN_SELECTIONDAG_ISEL_H
16 #define LLVM_CODEGEN_SELECTIONDAG_ISEL_H
18 #include "llvm/Pass.h"
19 #include "llvm/Constant.h"
20 #include "llvm/CodeGen/SelectionDAGNodes.h"
24 class SelectionDAGLowering;
27 class MachineBasicBlock;
28 class MachineFunction;
31 class FunctionLoweringInfo;
32 class HazardRecognizer;
34 /// SelectionDAGISel - This is the common base class used for SelectionDAG-based
35 /// pattern-matching instruction selectors.
36 class SelectionDAGISel : public FunctionPass {
41 MachineBasicBlock *BB;
43 SelectionDAGISel(TargetLowering &tli) : TLI(tli), JT(0,0,0,0) {}
45 virtual void getAnalysisUsage(AnalysisUsage &AU) const;
47 virtual bool runOnFunction(Function &Fn);
49 unsigned MakeReg(MVT::ValueType VT);
51 virtual void EmitFunctionEntryCode(Function &Fn, MachineFunction &MF) {}
52 virtual void InstructionSelectBasicBlock(SelectionDAG &SD) = 0;
54 /// SelectInlineAsmMemoryOperand - Select the specified address as a target
55 /// addressing mode, according to the specified constraint code. If this does
56 /// not match or is not implemented, return true. The resultant operands
57 /// (which will appear in the machine instruction) should be added to the
59 virtual bool SelectInlineAsmMemoryOperand(const SDOperand &Op,
61 std::vector<SDOperand> &OutOps,
66 /// CanBeFoldedBy - Returns true if the specific operand node N of U can be
67 /// folded during instruction selection?
68 virtual bool CanBeFoldedBy(SDNode *N, SDNode *U) { return true; }
70 /// CreateTargetHazardRecognizer - Return a newly allocated hazard recognizer
71 /// to use for this target when scheduling the DAG.
72 virtual HazardRecognizer *CreateTargetHazardRecognizer();
74 /// CaseBlock - This structure is used to communicate between SDLowering and
75 /// SDISel for the code generation of additional basic blocks needed by multi-
76 /// case switch statements.
78 CaseBlock(ISD::CondCode cc, Value *s, Constant *c, MachineBasicBlock *lhs,
79 MachineBasicBlock *rhs, MachineBasicBlock *me) :
80 CC(cc), SwitchV(s), CaseC(c), LHSBB(lhs), RHSBB(rhs), ThisBB(me) {}
81 // CC - the condition code to use for the case block's setcc node
83 // SwitchV - the value to be switched on, 'foo' in switch(foo)
85 // CaseC - the constant the setcc node will compare against SwitchV
87 // LHSBB - the block to branch to if the setcc is true
88 MachineBasicBlock *LHSBB;
89 // RHSBB - the block to branch to if the setcc is false
90 MachineBasicBlock *RHSBB;
91 // ThisBB - the blcok into which to emit the code for the setcc and branches
92 MachineBasicBlock *ThisBB;
95 JumpTable(unsigned R, unsigned J, MachineBasicBlock *M,
96 MachineBasicBlock *D) : Reg(R), JTI(J), MBB(M), Default(D) {}
97 // Reg - the virtual register containing the index of the jump table entry
100 // JTI - the JumpTableIndex for this jump table in the function.
102 // MBB - the MBB into which to emit the code for the indirect jump.
103 MachineBasicBlock *MBB;
104 // Default - the MBB of the default bb, which is a successor of the range
105 // check MBB. This is when updating PHI nodes in successors.
106 MachineBasicBlock *Default;
110 /// Pick a safe ordering and emit instructions for each target node in the
112 void ScheduleAndEmitDAG(SelectionDAG &DAG);
114 /// SelectInlineAsmMemoryOperands - Calls to this are automatically generated
115 /// by tblgen. Others should not call it.
116 void SelectInlineAsmMemoryOperands(std::vector<SDOperand> &Ops,
120 SDOperand CopyValueToVirtualRegister(SelectionDAGLowering &SDL,
121 Value *V, unsigned Reg);
122 void SelectBasicBlock(BasicBlock *BB, MachineFunction &MF,
123 FunctionLoweringInfo &FuncInfo);
125 void BuildSelectionDAG(SelectionDAG &DAG, BasicBlock *LLVMBB,
126 std::vector<std::pair<MachineInstr*, unsigned> > &PHINodesToUpdate,
127 FunctionLoweringInfo &FuncInfo);
128 void CodeGenAndEmitDAG(SelectionDAG &DAG);
129 void LowerArguments(BasicBlock *BB, SelectionDAGLowering &SDL,
130 std::vector<SDOperand> &UnorderedChains);
132 /// SwitchCases - Vector of CaseBlock structures used to communicate
133 /// SwitchInst code generation information.
134 std::vector<CaseBlock> SwitchCases;
136 /// JT - Record which holds necessary information for emitting a jump table
142 #endif /* LLVM_CODEGEN_SELECTIONDAG_ISEL_H */