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/SelectionDAG.h"
21 #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;
42 std::vector<SDNode*> TopOrder;
45 SelectionDAGISel(TargetLowering &tli) : TLI(tli), DAGSize(0), JT(0,0,0,0) {}
47 TargetLowering &getTargetLowering() { return TLI; }
49 virtual void getAnalysisUsage(AnalysisUsage &AU) const;
51 virtual bool runOnFunction(Function &Fn);
53 unsigned MakeReg(MVT::ValueType VT);
55 virtual void EmitFunctionEntryCode(Function &Fn, MachineFunction &MF) {}
56 virtual void InstructionSelectBasicBlock(SelectionDAG &SD) = 0;
57 virtual void SelectRootInit() {
58 DAGSize = CurDAG->AssignTopologicalOrder(TopOrder);
61 /// SelectInlineAsmMemoryOperand - Select the specified address as a target
62 /// addressing mode, according to the specified constraint code. If this does
63 /// not match or is not implemented, return true. The resultant operands
64 /// (which will appear in the machine instruction) should be added to the
66 virtual bool SelectInlineAsmMemoryOperand(const SDOperand &Op,
68 std::vector<SDOperand> &OutOps,
73 /// CanBeFoldedBy - Returns true if the specific operand node N of U can be
74 /// folded during instruction selection?
75 virtual bool CanBeFoldedBy(SDNode *N, SDNode *U) { return true; }
77 /// CreateTargetHazardRecognizer - Return a newly allocated hazard recognizer
78 /// to use for this target when scheduling the DAG.
79 virtual HazardRecognizer *CreateTargetHazardRecognizer();
81 /// CaseBlock - This structure is used to communicate between SDLowering and
82 /// SDISel for the code generation of additional basic blocks needed by multi-
83 /// case switch statements.
85 CaseBlock(ISD::CondCode cc, Value *s, Constant *c, MachineBasicBlock *lhs,
86 MachineBasicBlock *rhs, MachineBasicBlock *me) :
87 CC(cc), SwitchV(s), CaseC(c), LHSBB(lhs), RHSBB(rhs), ThisBB(me) {}
88 // CC - the condition code to use for the case block's setcc node
90 // SwitchV - the value to be switched on, 'foo' in switch(foo)
92 // CaseC - the constant the setcc node will compare against SwitchV
94 // LHSBB - the block to branch to if the setcc is true
95 MachineBasicBlock *LHSBB;
96 // RHSBB - the block to branch to if the setcc is false
97 MachineBasicBlock *RHSBB;
98 // ThisBB - the blcok into which to emit the code for the setcc and branches
99 MachineBasicBlock *ThisBB;
102 JumpTable(unsigned R, unsigned J, MachineBasicBlock *M,
103 MachineBasicBlock *D) : Reg(R), JTI(J), MBB(M), Default(D) {}
104 // Reg - the virtual register containing the index of the jump table entry
107 // JTI - the JumpTableIndex for this jump table in the function.
109 // MBB - the MBB into which to emit the code for the indirect jump.
110 MachineBasicBlock *MBB;
111 // Default - the MBB of the default bb, which is a successor of the range
112 // check MBB. This is when updating PHI nodes in successors.
113 MachineBasicBlock *Default;
117 /// Pick a safe ordering and emit instructions for each target node in the
119 void ScheduleAndEmitDAG(SelectionDAG &DAG);
121 /// SelectInlineAsmMemoryOperands - Calls to this are automatically generated
122 /// by tblgen. Others should not call it.
123 void SelectInlineAsmMemoryOperands(std::vector<SDOperand> &Ops,
126 // Calls to these predicates are generated by tblgen.
127 bool CheckAndMask(SDOperand LHS, ConstantSDNode *RHS, int64_t DesiredMaskS);
128 bool CheckOrMask(SDOperand LHS, ConstantSDNode *RHS, int64_t DesiredMaskS);
131 void SplitCritEdgesForPHIConstants(BasicBlock *BB);
132 SDOperand CopyValueToVirtualRegister(SelectionDAGLowering &SDL,
133 Value *V, unsigned Reg);
134 void SelectBasicBlock(BasicBlock *BB, MachineFunction &MF,
135 FunctionLoweringInfo &FuncInfo);
137 void BuildSelectionDAG(SelectionDAG &DAG, BasicBlock *LLVMBB,
138 std::vector<std::pair<MachineInstr*, unsigned> > &PHINodesToUpdate,
139 FunctionLoweringInfo &FuncInfo);
140 void CodeGenAndEmitDAG(SelectionDAG &DAG);
141 void LowerArguments(BasicBlock *BB, SelectionDAGLowering &SDL,
142 std::vector<SDOperand> &UnorderedChains);
144 /// SwitchCases - Vector of CaseBlock structures used to communicate
145 /// SwitchInst code generation information.
146 std::vector<CaseBlock> SwitchCases;
148 /// JT - Record which holds necessary information for emitting a jump table
154 #endif /* LLVM_CODEGEN_SELECTIONDAG_ISEL_H */