aboutsummaryrefslogtreecommitdiff
path: root/lib/Target/AVR/AVRISelLowering.h
blob: ed2d0835903c4c5b727275e730e68ad2e25ab763 (plain) (blame)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
//===-- AVRISelLowering.h - AVR DAG Lowering Interface ----------*- C++ -*-===//
//
// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
// See https://llvm.org/LICENSE.txt for license information.
// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
//
//===----------------------------------------------------------------------===//
//
// This file defines the interfaces that AVR uses to lower LLVM code into a
// selection DAG.
//
//===----------------------------------------------------------------------===//

#ifndef LLVM_AVR_ISEL_LOWERING_H
#define LLVM_AVR_ISEL_LOWERING_H

#include "llvm/CodeGen/CallingConvLower.h"
#include "llvm/CodeGen/TargetLowering.h"

namespace llvm {

namespace AVRISD {

/// AVR Specific DAG Nodes
enum NodeType {
  /// Start the numbering where the builtin ops leave off.
  FIRST_NUMBER = ISD::BUILTIN_OP_END,
  /// Return from subroutine.
  RET_FLAG,
  /// Return from ISR.
  RETI_FLAG,
  /// Represents an abstract call instruction,
  /// which includes a bunch of information.
  CALL,
  /// A wrapper node for TargetConstantPool,
  /// TargetExternalSymbol, and TargetGlobalAddress.
  WRAPPER,
  LSL,     ///< Logical shift left.
  LSR,     ///< Logical shift right.
  ASR,     ///< Arithmetic shift right.
  ROR,     ///< Bit rotate right.
  ROL,     ///< Bit rotate left.
  LSLLOOP, ///< A loop of single logical shift left instructions.
  LSRLOOP, ///< A loop of single logical shift right instructions.
  ROLLOOP, ///< A loop of single left bit rotate instructions.
  RORLOOP, ///< A loop of single right bit rotate instructions.
  ASRLOOP, ///< A loop of single arithmetic shift right instructions.
  /// AVR conditional branches. Operand 0 is the chain operand, operand 1
  /// is the block to branch if condition is true, operand 2 is the
  /// condition code, and operand 3 is the flag operand produced by a CMP
  /// or TEST instruction.
  BRCOND,
  /// Compare instruction.
  CMP,
  /// Compare with carry instruction.
  CMPC,
  /// Test for zero or minus instruction.
  TST,
  /// Operand 0 and operand 1 are selection variable, operand 2
  /// is condition code and operand 3 is flag operand.
  SELECT_CC
};

} // end of namespace AVRISD

class AVRSubtarget;
class AVRTargetMachine;

/// Performs target lowering for the AVR.
class AVRTargetLowering : public TargetLowering {
public:
  explicit AVRTargetLowering(const AVRTargetMachine &TM,
                             const AVRSubtarget &STI);

public:
  MVT getScalarShiftAmountTy(const DataLayout &, EVT LHSTy) const override {
    return MVT::i8;
  }

  MVT::SimpleValueType getCmpLibcallReturnType() const override {
    return MVT::i8;
  }

  const char *getTargetNodeName(unsigned Opcode) const override;

  SDValue LowerOperation(SDValue Op, SelectionDAG &DAG) const override;

  void ReplaceNodeResults(SDNode *N, SmallVectorImpl<SDValue> &Results,
                          SelectionDAG &DAG) const override;

  bool isLegalAddressingMode(const DataLayout &DL, const AddrMode &AM, Type *Ty,
                             unsigned AS,
                             Instruction *I = nullptr) const override;

  bool getPreIndexedAddressParts(SDNode *N, SDValue &Base, SDValue &Offset,
                                 ISD::MemIndexedMode &AM,
                                 SelectionDAG &DAG) const override;

  bool getPostIndexedAddressParts(SDNode *N, SDNode *Op, SDValue &Base,
                                  SDValue &Offset, ISD::MemIndexedMode &AM,
                                  SelectionDAG &DAG) const override;

  bool isOffsetFoldingLegal(const GlobalAddressSDNode *GA) const override;

  EVT getSetCCResultType(const DataLayout &DL, LLVMContext &Context,
                         EVT VT) const override;

  MachineBasicBlock *
  EmitInstrWithCustomInserter(MachineInstr &MI,
                              MachineBasicBlock *MBB) const override;

  ConstraintType getConstraintType(StringRef Constraint) const override;

  ConstraintWeight
  getSingleConstraintMatchWeight(AsmOperandInfo &info,
                                 const char *constraint) const override;

  std::pair<unsigned, const TargetRegisterClass *>
  getRegForInlineAsmConstraint(const TargetRegisterInfo *TRI,
                               StringRef Constraint, MVT VT) const override;

  unsigned getInlineAsmMemConstraint(StringRef ConstraintCode) const override;

  void LowerAsmOperandForConstraint(SDValue Op, std::string &Constraint,
                                    std::vector<SDValue> &Ops,
                                    SelectionDAG &DAG) const override;

  unsigned getRegisterByName(const char* RegName, EVT VT,
                             SelectionDAG &DAG) const override;

  bool shouldSplitFunctionArgumentsAsLittleEndian(const DataLayout &DL)
    const override {
    return false;
  }

private:
  SDValue getAVRCmp(SDValue LHS, SDValue RHS, ISD::CondCode CC, SDValue &AVRcc,
                    SelectionDAG &DAG, SDLoc dl) const;
  SDValue LowerShifts(SDValue Op, SelectionDAG &DAG) const;
  SDValue LowerDivRem(SDValue Op, SelectionDAG &DAG) const;
  SDValue LowerGlobalAddress(SDValue Op, SelectionDAG &DAG) const;
  SDValue LowerBlockAddress(SDValue Op, SelectionDAG &DAG) const;
  SDValue LowerBR_CC(SDValue Op, SelectionDAG &DAG) const;
  SDValue LowerINLINEASM(SDValue Op, SelectionDAG &DAG) const;
  SDValue LowerSELECT_CC(SDValue Op, SelectionDAG &DAG) const;
  SDValue LowerSETCC(SDValue Op, SelectionDAG &DAG) const;
  SDValue LowerVASTART(SDValue Op, SelectionDAG &DAG) const;

  CCAssignFn *CCAssignFnForReturn(CallingConv::ID CC) const;

  bool CanLowerReturn(CallingConv::ID CallConv,
                      MachineFunction &MF, bool isVarArg,
                      const SmallVectorImpl<ISD::OutputArg> &Outs,
                      LLVMContext &Context) const override;

  SDValue LowerReturn(SDValue Chain, CallingConv::ID CallConv, bool isVarArg,
                      const SmallVectorImpl<ISD::OutputArg> &Outs,
                      const SmallVectorImpl<SDValue> &OutVals, const SDLoc &dl,
                      SelectionDAG &DAG) const override;
  SDValue LowerFormalArguments(SDValue Chain, CallingConv::ID CallConv,
                               bool isVarArg,
                               const SmallVectorImpl<ISD::InputArg> &Ins,
                               const SDLoc &dl, SelectionDAG &DAG,
                               SmallVectorImpl<SDValue> &InVals) const override;
  SDValue LowerCall(TargetLowering::CallLoweringInfo &CLI,
                    SmallVectorImpl<SDValue> &InVals) const override;
  SDValue LowerCallResult(SDValue Chain, SDValue InFlag,
                          CallingConv::ID CallConv, bool isVarArg,
                          const SmallVectorImpl<ISD::InputArg> &Ins,
                          const SDLoc &dl, SelectionDAG &DAG,
                          SmallVectorImpl<SDValue> &InVals) const;

protected:

  const AVRSubtarget &Subtarget;

private:
  MachineBasicBlock *insertShift(MachineInstr &MI, MachineBasicBlock *BB) const;
  MachineBasicBlock *insertMul(MachineInstr &MI, MachineBasicBlock *BB) const;
};

} // end namespace llvm

#endif // LLVM_AVR_ISEL_LOWERING_H