aboutsummaryrefslogtreecommitdiff
path: root/lib/Target/ARC/ARCISelDAGToDAG.cpp
blob: 8dbd3d5bf036ef3221569495aa46b565e95192a0 (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
//===- ARCISelDAGToDAG.cpp - ARC dag to dag inst selector -------*- C++ -*-===//
//
//                     The LLVM Compiler Infrastructure
//
// This file is distributed under the University of Illinois Open Source
// License. See LICENSE.TXT for details.
//
//===----------------------------------------------------------------------===//
//
// This file defines an instruction selector for the ARC target.
//
//===----------------------------------------------------------------------===//

#include "ARC.h"
#include "ARCTargetMachine.h"
#include "llvm/CodeGen/MachineFrameInfo.h"
#include "llvm/CodeGen/MachineFunction.h"
#include "llvm/CodeGen/MachineInstrBuilder.h"
#include "llvm/CodeGen/MachineRegisterInfo.h"
#include "llvm/CodeGen/SelectionDAG.h"
#include "llvm/CodeGen/SelectionDAGISel.h"
#include "llvm/CodeGen/TargetLowering.h"
#include "llvm/IR/CallingConv.h"
#include "llvm/IR/Constants.h"
#include "llvm/IR/DerivedTypes.h"
#include "llvm/IR/Function.h"
#include "llvm/IR/Intrinsics.h"
#include "llvm/IR/LLVMContext.h"
#include "llvm/Support/Compiler.h"
#include "llvm/Support/Debug.h"
#include "llvm/Support/ErrorHandling.h"
#include "llvm/Support/raw_ostream.h"

using namespace llvm;

/// ARCDAGToDAGISel - ARC specific code to select ARC machine
/// instructions for SelectionDAG operations.
namespace {

class ARCDAGToDAGISel : public SelectionDAGISel {
public:
  ARCDAGToDAGISel(ARCTargetMachine &TM, CodeGenOpt::Level OptLevel)
      : SelectionDAGISel(TM, OptLevel) {}

  void Select(SDNode *N) override;

  // Complex Pattern Selectors.
  bool SelectFrameADDR_ri(SDValue Addr, SDValue &Base, SDValue &Offset);
  bool SelectAddrModeS9(SDValue Addr, SDValue &Base, SDValue &Offset);
  bool SelectAddrModeImm(SDValue Addr, SDValue &Base, SDValue &Offset);
  bool SelectAddrModeFar(SDValue Addr, SDValue &Base, SDValue &Offset);
  bool SelectCMOVPred(SDValue N, SDValue &Pred, SDValue &Reg) {
    const ConstantSDNode *CN = cast<ConstantSDNode>(N);
    Pred = CurDAG->getTargetConstant(CN->getZExtValue(), SDLoc(N), MVT::i32);
    Reg = CurDAG->getRegister(ARC::STATUS32, MVT::i32);
    return true;
  }

  StringRef getPassName() const override {
    return "ARC DAG->DAG Pattern Instruction Selection";
  }

// Include the pieces autogenerated from the target description.
#include "ARCGenDAGISel.inc"
};

} // end anonymous namespace

/// This pass converts a legalized DAG into a ARC-specific DAG, ready for
/// instruction scheduling.
FunctionPass *llvm::createARCISelDag(ARCTargetMachine &TM,
                                     CodeGenOpt::Level OptLevel) {
  return new ARCDAGToDAGISel(TM, OptLevel);
}

bool ARCDAGToDAGISel::SelectAddrModeImm(SDValue Addr, SDValue &Base,
                                        SDValue &Offset) {
  if (Addr.getOpcode() == ARCISD::GAWRAPPER) {
    Base = Addr.getOperand(0);
    Offset = CurDAG->getTargetConstant(0, SDLoc(Addr), MVT::i32);
    return true;
  }
  return false;
}

bool ARCDAGToDAGISel::SelectAddrModeS9(SDValue Addr, SDValue &Base,
                                       SDValue &Offset) {
  if (Addr.getOpcode() == ARCISD::GAWRAPPER) {
    return false;
  }

  if (Addr.getOpcode() != ISD::ADD && Addr.getOpcode() != ISD::SUB &&
      !CurDAG->isBaseWithConstantOffset(Addr)) {
    if (Addr.getOpcode() == ISD::FrameIndex) {
      // Match frame index.
      int FI = cast<FrameIndexSDNode>(Addr)->getIndex();
      Base = CurDAG->getTargetFrameIndex(
          FI, TLI->getPointerTy(CurDAG->getDataLayout()));
    } else {
      Base = Addr;
    }
    Offset = CurDAG->getTargetConstant(0, SDLoc(Addr), MVT::i32);
    return true;
  }

  if (ConstantSDNode *RHS = dyn_cast<ConstantSDNode>(Addr.getOperand(1))) {
    int32_t RHSC = RHS->getSExtValue();
    if (Addr.getOpcode() == ISD::SUB)
      RHSC = -RHSC;

    // Do we need more than 9 bits to encode?
    if (!isInt<9>(RHSC))
      return false;
    Base = Addr.getOperand(0);
    if (Base.getOpcode() == ISD::FrameIndex) {
      int FI = cast<FrameIndexSDNode>(Base)->getIndex();
      Base = CurDAG->getTargetFrameIndex(
          FI, TLI->getPointerTy(CurDAG->getDataLayout()));
    }
    Offset = CurDAG->getTargetConstant(RHSC, SDLoc(Addr), MVT::i32);
    return true;
  }
  Base = Addr;
  Offset = CurDAG->getTargetConstant(0, SDLoc(Addr), MVT::i32);
  return true;
}

bool ARCDAGToDAGISel::SelectAddrModeFar(SDValue Addr, SDValue &Base,
                                        SDValue &Offset) {
  if (SelectAddrModeS9(Addr, Base, Offset))
    return false;
  if (Addr.getOpcode() == ARCISD::GAWRAPPER) {
    return false;
  }
  if (ConstantSDNode *RHS = dyn_cast<ConstantSDNode>(Addr.getOperand(1))) {
    int32_t RHSC = RHS->getSExtValue();
    if (Addr.getOpcode() == ISD::SUB)
      RHSC = -RHSC;
    Base = Addr.getOperand(0);
    Offset = CurDAG->getTargetConstant(RHSC, SDLoc(Addr), MVT::i32);
    return true;
  }
  return false;
}

// Is this a legal frame index addressing expression.
bool ARCDAGToDAGISel::SelectFrameADDR_ri(SDValue Addr, SDValue &Base,
                                         SDValue &Offset) {
  FrameIndexSDNode *FIN = nullptr;
  if ((FIN = dyn_cast<FrameIndexSDNode>(Addr))) {
    Base = CurDAG->getTargetFrameIndex(FIN->getIndex(), MVT::i32);
    Offset = CurDAG->getTargetConstant(0, SDLoc(Addr), MVT::i32);
    return true;
  }
  if (Addr.getOpcode() == ISD::ADD) {
    ConstantSDNode *CN = nullptr;
    if ((FIN = dyn_cast<FrameIndexSDNode>(Addr.getOperand(0))) &&
        (CN = dyn_cast<ConstantSDNode>(Addr.getOperand(1))) &&
        (CN->getSExtValue() % 4 == 0 && CN->getSExtValue() >= 0)) {
      // Constant positive word offset from frame index
      Base = CurDAG->getTargetFrameIndex(FIN->getIndex(), MVT::i32);
      Offset =
          CurDAG->getTargetConstant(CN->getSExtValue(), SDLoc(Addr), MVT::i32);
      return true;
    }
  }
  return false;
}

void ARCDAGToDAGISel::Select(SDNode *N) {
  switch (N->getOpcode()) {
  case ISD::Constant: {
    uint64_t CVal = cast<ConstantSDNode>(N)->getZExtValue();
    ReplaceNode(N, CurDAG->getMachineNode(
                       isInt<12>(CVal) ? ARC::MOV_rs12 : ARC::MOV_rlimm,
                       SDLoc(N), MVT::i32,
                       CurDAG->getTargetConstant(CVal, SDLoc(N), MVT::i32)));
    return;
  }
  }
  SelectCode(N);
}