1//===- HexagonMCInstLower.cpp - Convert Hexagon MachineInstr to an MCInst -===//
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 contains code to lower Hexagon MachineInstrs to their corresponding
10// MCInst records.
11//
12//===----------------------------------------------------------------------===//
13
14#include "Hexagon.h"
15#include "HexagonAsmPrinter.h"
16#include "MCTargetDesc/HexagonMCExpr.h"
17#include "MCTargetDesc/HexagonMCInstrInfo.h"
18#include "MCTargetDesc/HexagonMCTargetDesc.h"
19#include "llvm/ADT/APFloat.h"
20#include "llvm/ADT/APInt.h"
21#include "llvm/CodeGen/MachineBasicBlock.h"
22#include "llvm/CodeGen/MachineInstr.h"
23#include "llvm/CodeGen/MachineOperand.h"
24#include "llvm/IR/Constants.h"
25#include "llvm/MC/MCContext.h"
26#include "llvm/MC/MCExpr.h"
27#include "llvm/MC/MCInst.h"
28#include "llvm/Support/ErrorHandling.h"
29#include "llvm/Support/raw_ostream.h"
30#include <cassert>
31
32using namespace llvm;
33
34namespace llvm {
35
36void HexagonLowerToMC(const MCInstrInfo &MCII, const MachineInstr *MI,
37                      MCInst &MCB, HexagonAsmPrinter &AP);
38
39} // end namespace llvm
40
41static MCOperand GetSymbolRef(const MachineOperand &MO, const MCSymbol *Symbol,
42                              HexagonAsmPrinter &Printer, bool MustExtend) {
43  MCContext &MC = Printer.OutContext;
44  const MCExpr *ME;
45
46  // Populate the relocation type based on Hexagon target flags
47  // set on an operand
48  MCSymbolRefExpr::VariantKind RelocationType;
49  switch (MO.getTargetFlags() & ~HexagonII::HMOTF_ConstExtended) {
50  default:
51    RelocationType = MCSymbolRefExpr::VK_None;
52    break;
53  case HexagonII::MO_PCREL:
54    RelocationType = MCSymbolRefExpr::VK_PCREL;
55    break;
56  case HexagonII::MO_GOT:
57    RelocationType = MCSymbolRefExpr::VK_GOT;
58    break;
59  case HexagonII::MO_LO16:
60    RelocationType = MCSymbolRefExpr::VK_Hexagon_LO16;
61    break;
62  case HexagonII::MO_HI16:
63    RelocationType = MCSymbolRefExpr::VK_Hexagon_HI16;
64    break;
65  case HexagonII::MO_GPREL:
66    RelocationType = MCSymbolRefExpr::VK_Hexagon_GPREL;
67    break;
68  case HexagonII::MO_GDGOT:
69    RelocationType = MCSymbolRefExpr::VK_Hexagon_GD_GOT;
70    break;
71  case HexagonII::MO_GDPLT:
72    RelocationType = MCSymbolRefExpr::VK_Hexagon_GD_PLT;
73    break;
74  case HexagonII::MO_IE:
75    RelocationType = MCSymbolRefExpr::VK_Hexagon_IE;
76    break;
77  case HexagonII::MO_IEGOT:
78    RelocationType = MCSymbolRefExpr::VK_Hexagon_IE_GOT;
79    break;
80  case HexagonII::MO_TPREL:
81    RelocationType = MCSymbolRefExpr::VK_TPREL;
82    break;
83  }
84
85  ME = MCSymbolRefExpr::create(Symbol, RelocationType, MC);
86
87  if (!MO.isJTI() && MO.getOffset())
88    ME = MCBinaryExpr::createAdd(ME, MCConstantExpr::create(MO.getOffset(), MC),
89                                 MC);
90
91  ME = HexagonMCExpr::create(ME, MC);
92  HexagonMCInstrInfo::setMustExtend(*ME, MustExtend);
93  return MCOperand::createExpr(ME);
94}
95
96// Create an MCInst from a MachineInstr
97void llvm::HexagonLowerToMC(const MCInstrInfo &MCII, const MachineInstr *MI,
98                            MCInst &MCB, HexagonAsmPrinter &AP) {
99  if (MI->getOpcode() == Hexagon::ENDLOOP0) {
100    HexagonMCInstrInfo::setInnerLoop(MCB);
101    return;
102  }
103  if (MI->getOpcode() == Hexagon::ENDLOOP1) {
104    HexagonMCInstrInfo::setOuterLoop(MCB);
105    return;
106  }
107  MCInst *MCI = new (AP.OutContext) MCInst;
108  MCI->setOpcode(MI->getOpcode());
109  assert(MCI->getOpcode() == static_cast<unsigned>(MI->getOpcode()) &&
110         "MCI opcode should have been set on construction");
111
112  for (unsigned i = 0, e = MI->getNumOperands(); i < e; i++) {
113    const MachineOperand &MO = MI->getOperand(i);
114    MCOperand MCO;
115    bool MustExtend = MO.getTargetFlags() & HexagonII::HMOTF_ConstExtended;
116
117    switch (MO.getType()) {
118    default:
119      MI->print(errs());
120      llvm_unreachable("unknown operand type");
121    case MachineOperand::MO_RegisterMask:
122      continue;
123    case MachineOperand::MO_Register:
124      // Ignore all implicit register operands.
125      if (MO.isImplicit())
126        continue;
127      MCO = MCOperand::createReg(MO.getReg());
128      break;
129    case MachineOperand::MO_FPImmediate: {
130      APFloat Val = MO.getFPImm()->getValueAPF();
131      // FP immediates are used only when setting GPRs, so they may be dealt
132      // with like regular immediates from this point on.
133      auto Expr = HexagonMCExpr::create(
134          MCConstantExpr::create(*Val.bitcastToAPInt().getRawData(),
135                                 AP.OutContext),
136          AP.OutContext);
137      HexagonMCInstrInfo::setMustExtend(*Expr, MustExtend);
138      MCO = MCOperand::createExpr(Expr);
139      break;
140    }
141    case MachineOperand::MO_Immediate: {
142      auto Expr = HexagonMCExpr::create(
143          MCConstantExpr::create(MO.getImm(), AP.OutContext), AP.OutContext);
144      HexagonMCInstrInfo::setMustExtend(*Expr, MustExtend);
145      MCO = MCOperand::createExpr(Expr);
146      break;
147    }
148    case MachineOperand::MO_MachineBasicBlock: {
149      MCExpr const *Expr = MCSymbolRefExpr::create(MO.getMBB()->getSymbol(),
150                                                   AP.OutContext);
151      Expr = HexagonMCExpr::create(Expr, AP.OutContext);
152      HexagonMCInstrInfo::setMustExtend(*Expr, MustExtend);
153      MCO = MCOperand::createExpr(Expr);
154      break;
155    }
156    case MachineOperand::MO_GlobalAddress:
157      MCO = GetSymbolRef(MO, AP.getSymbol(MO.getGlobal()), AP, MustExtend);
158      break;
159    case MachineOperand::MO_ExternalSymbol:
160      MCO = GetSymbolRef(MO, AP.GetExternalSymbolSymbol(MO.getSymbolName()),
161                         AP, MustExtend);
162      break;
163    case MachineOperand::MO_JumpTableIndex:
164      MCO = GetSymbolRef(MO, AP.GetJTISymbol(MO.getIndex()), AP, MustExtend);
165      break;
166    case MachineOperand::MO_ConstantPoolIndex:
167      MCO = GetSymbolRef(MO, AP.GetCPISymbol(MO.getIndex()), AP, MustExtend);
168      break;
169    case MachineOperand::MO_BlockAddress:
170      MCO = GetSymbolRef(MO, AP.GetBlockAddressSymbol(MO.getBlockAddress()), AP,
171                         MustExtend);
172      break;
173    }
174
175    MCI->addOperand(MCO);
176  }
177  AP.HexagonProcessInstruction(*MCI, *MI);
178  HexagonMCInstrInfo::extendIfNeeded(AP.OutContext, MCII, MCB, *MCI);
179  MCB.addOperand(MCOperand::createInst(MCI));
180}
181