xref: /freebsd/contrib/llvm-project/llvm/lib/Target/Mips/MipsISelDAGToDAG.h (revision 68d75eff68281c1b445e3010bb975eae07aac225)
1 //===---- MipsISelDAGToDAG.h - A Dag to Dag Inst Selector for Mips --------===//
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 defines an instruction selector for the MIPS target.
10 //
11 //===----------------------------------------------------------------------===//
12 
13 #ifndef LLVM_LIB_TARGET_MIPS_MIPSISELDAGTODAG_H
14 #define LLVM_LIB_TARGET_MIPS_MIPSISELDAGTODAG_H
15 
16 #include "Mips.h"
17 #include "MipsSubtarget.h"
18 #include "MipsTargetMachine.h"
19 #include "llvm/CodeGen/SelectionDAGISel.h"
20 
21 //===----------------------------------------------------------------------===//
22 // Instruction Selector Implementation
23 //===----------------------------------------------------------------------===//
24 
25 //===----------------------------------------------------------------------===//
26 // MipsDAGToDAGISel - MIPS specific code to select MIPS machine
27 // instructions for SelectionDAG operations.
28 //===----------------------------------------------------------------------===//
29 namespace llvm {
30 
31 class MipsDAGToDAGISel : public SelectionDAGISel {
32 public:
33   explicit MipsDAGToDAGISel(MipsTargetMachine &TM, CodeGenOpt::Level OL)
34       : SelectionDAGISel(TM, OL), Subtarget(nullptr) {}
35 
36   // Pass Name
37   StringRef getPassName() const override {
38     return "MIPS DAG->DAG Pattern Instruction Selection";
39   }
40 
41   bool runOnMachineFunction(MachineFunction &MF) override;
42 
43   void getAnalysisUsage(AnalysisUsage &AU) const override;
44 
45 protected:
46   SDNode *getGlobalBaseReg();
47 
48   /// Keep a pointer to the MipsSubtarget around so that we can make the right
49   /// decision when generating code for different targets.
50   const MipsSubtarget *Subtarget;
51 
52 private:
53   // Include the pieces autogenerated from the target description.
54   #include "MipsGenDAGISel.inc"
55 
56   // Complex Pattern.
57   /// (reg + imm).
58   virtual bool selectAddrRegImm(SDValue Addr, SDValue &Base,
59                                 SDValue &Offset) const;
60 
61   /// Fall back on this function if all else fails.
62   virtual bool selectAddrDefault(SDValue Addr, SDValue &Base,
63                                  SDValue &Offset) const;
64 
65   /// Match integer address pattern.
66   virtual bool selectIntAddr(SDValue Addr, SDValue &Base,
67                              SDValue &Offset) const;
68 
69   virtual bool selectIntAddr11MM(SDValue Addr, SDValue &Base,
70                                  SDValue &Offset) const;
71 
72   virtual bool selectIntAddr12MM(SDValue Addr, SDValue &Base,
73                                SDValue &Offset) const;
74 
75   virtual bool selectIntAddr16MM(SDValue Addr, SDValue &Base,
76                                  SDValue &Offset) const;
77 
78   virtual bool selectIntAddrLSL2MM(SDValue Addr, SDValue &Base,
79                                    SDValue &Offset) const;
80 
81   /// Match addr+simm10 and addr
82   virtual bool selectIntAddrSImm10(SDValue Addr, SDValue &Base,
83                                    SDValue &Offset) const;
84 
85   virtual bool selectIntAddrSImm10Lsl1(SDValue Addr, SDValue &Base,
86                                        SDValue &Offset) const;
87 
88   virtual bool selectIntAddrSImm10Lsl2(SDValue Addr, SDValue &Base,
89                                        SDValue &Offset) const;
90 
91   virtual bool selectIntAddrSImm10Lsl3(SDValue Addr, SDValue &Base,
92                                        SDValue &Offset) const;
93 
94   virtual bool selectAddr16(SDValue Addr, SDValue &Base, SDValue &Offset);
95   virtual bool selectAddr16SP(SDValue Addr, SDValue &Base, SDValue &Offset);
96 
97   /// Select constant vector splats.
98   virtual bool selectVSplat(SDNode *N, APInt &Imm,
99                             unsigned MinSizeInBits) const;
100   /// Select constant vector splats whose value fits in a uimm1.
101   virtual bool selectVSplatUimm1(SDValue N, SDValue &Imm) const;
102   /// Select constant vector splats whose value fits in a uimm2.
103   virtual bool selectVSplatUimm2(SDValue N, SDValue &Imm) const;
104   /// Select constant vector splats whose value fits in a uimm3.
105   virtual bool selectVSplatUimm3(SDValue N, SDValue &Imm) const;
106   /// Select constant vector splats whose value fits in a uimm4.
107   virtual bool selectVSplatUimm4(SDValue N, SDValue &Imm) const;
108   /// Select constant vector splats whose value fits in a uimm5.
109   virtual bool selectVSplatUimm5(SDValue N, SDValue &Imm) const;
110   /// Select constant vector splats whose value fits in a uimm6.
111   virtual bool selectVSplatUimm6(SDValue N, SDValue &Imm) const;
112   /// Select constant vector splats whose value fits in a uimm8.
113   virtual bool selectVSplatUimm8(SDValue N, SDValue &Imm) const;
114   /// Select constant vector splats whose value fits in a simm5.
115   virtual bool selectVSplatSimm5(SDValue N, SDValue &Imm) const;
116   /// Select constant vector splats whose value is a power of 2.
117   virtual bool selectVSplatUimmPow2(SDValue N, SDValue &Imm) const;
118   /// Select constant vector splats whose value is the inverse of a
119   /// power of 2.
120   virtual bool selectVSplatUimmInvPow2(SDValue N, SDValue &Imm) const;
121   /// Select constant vector splats whose value is a run of set bits
122   /// ending at the most significant bit
123   virtual bool selectVSplatMaskL(SDValue N, SDValue &Imm) const;
124   /// Select constant vector splats whose value is a run of set bits
125   /// starting at bit zero.
126   virtual bool selectVSplatMaskR(SDValue N, SDValue &Imm) const;
127 
128   /// Convert vector addition with vector subtraction if that allows to encode
129   /// constant as an immediate and thus avoid extra 'ldi' instruction.
130   /// add X, <-1, -1...> --> sub X, <1, 1...>
131   bool selectVecAddAsVecSubIfProfitable(SDNode *Node);
132 
133   void Select(SDNode *N) override;
134 
135   virtual bool trySelect(SDNode *Node) = 0;
136 
137   // getImm - Return a target constant with the specified value.
138   inline SDValue getImm(const SDNode *Node, uint64_t Imm) {
139     return CurDAG->getTargetConstant(Imm, SDLoc(Node), Node->getValueType(0));
140   }
141 
142   virtual void processFunctionAfterISel(MachineFunction &MF) = 0;
143 
144   bool SelectInlineAsmMemoryOperand(const SDValue &Op,
145                                     unsigned ConstraintID,
146                                     std::vector<SDValue> &OutOps) override;
147 };
148 }
149 
150 #endif
151