1//===-- AVRMCInstLower.cpp - Convert AVR 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 AVR MachineInstrs to their corresponding
10// MCInst records.
11//
12//===----------------------------------------------------------------------===//
13
14#include "AVRMCInstLower.h"
15#include "AVRInstrInfo.h"
16#include "MCTargetDesc/AVRMCExpr.h"
17
18#include "llvm/CodeGen/AsmPrinter.h"
19#include "llvm/IR/Mangler.h"
20#include "llvm/MC/MCInst.h"
21#include "llvm/Support/ErrorHandling.h"
22
23namespace llvm {
24
25MCOperand
26AVRMCInstLower::lowerSymbolOperand(const MachineOperand &MO, MCSymbol *Sym,
27                                   const AVRSubtarget &Subtarget) const {
28  unsigned char TF = MO.getTargetFlags();
29  const MCExpr *Expr = MCSymbolRefExpr::create(Sym, Ctx);
30
31  bool IsNegated = false;
32  if (TF & AVRII::MO_NEG) {
33    IsNegated = true;
34  }
35
36  if (!MO.isJTI() && MO.getOffset()) {
37    Expr = MCBinaryExpr::createAdd(
38        Expr, MCConstantExpr::create(MO.getOffset(), Ctx), Ctx);
39  }
40
41  bool IsFunction = MO.isGlobal() && isa<Function>(MO.getGlobal());
42
43  if (TF & AVRII::MO_LO) {
44    if (IsFunction) {
45      Expr =
46          AVRMCExpr::create(Subtarget.hasEIJMPCALL() ? AVRMCExpr::VK_AVR_LO8_GS
47                                                     : AVRMCExpr::VK_AVR_PM_LO8,
48                            Expr, IsNegated, Ctx);
49    } else {
50      Expr = AVRMCExpr::create(AVRMCExpr::VK_AVR_LO8, Expr, IsNegated, Ctx);
51    }
52  } else if (TF & AVRII::MO_HI) {
53    if (IsFunction) {
54      Expr =
55          AVRMCExpr::create(Subtarget.hasEIJMPCALL() ? AVRMCExpr::VK_AVR_HI8_GS
56                                                     : AVRMCExpr::VK_AVR_PM_HI8,
57                            Expr, IsNegated, Ctx);
58    } else {
59      Expr = AVRMCExpr::create(AVRMCExpr::VK_AVR_HI8, Expr, IsNegated, Ctx);
60    }
61  } else if (TF != 0) {
62    llvm_unreachable("Unknown target flag on symbol operand");
63  }
64
65  return MCOperand::createExpr(Expr);
66}
67
68void AVRMCInstLower::lowerInstruction(const MachineInstr &MI,
69                                      MCInst &OutMI) const {
70  auto &Subtarget = MI.getParent()->getParent()->getSubtarget<AVRSubtarget>();
71  OutMI.setOpcode(MI.getOpcode());
72
73  for (MachineOperand const &MO : MI.operands()) {
74    MCOperand MCOp;
75
76    switch (MO.getType()) {
77    default:
78      MI.print(errs());
79      llvm_unreachable("unknown operand type");
80    case MachineOperand::MO_Register:
81      // Ignore all implicit register operands.
82      if (MO.isImplicit())
83        continue;
84      MCOp = MCOperand::createReg(MO.getReg());
85      break;
86    case MachineOperand::MO_Immediate:
87      MCOp = MCOperand::createImm(MO.getImm());
88      break;
89    case MachineOperand::MO_GlobalAddress:
90      MCOp =
91          lowerSymbolOperand(MO, Printer.getSymbol(MO.getGlobal()), Subtarget);
92      break;
93    case MachineOperand::MO_ExternalSymbol:
94      MCOp = lowerSymbolOperand(
95          MO, Printer.GetExternalSymbolSymbol(MO.getSymbolName()), Subtarget);
96      break;
97    case MachineOperand::MO_MachineBasicBlock:
98      MCOp = MCOperand::createExpr(
99          MCSymbolRefExpr::create(MO.getMBB()->getSymbol(), Ctx));
100      break;
101    case MachineOperand::MO_RegisterMask:
102      continue;
103    case MachineOperand::MO_BlockAddress:
104      MCOp = lowerSymbolOperand(
105          MO, Printer.GetBlockAddressSymbol(MO.getBlockAddress()), Subtarget);
106      break;
107    case MachineOperand::MO_JumpTableIndex:
108      MCOp = lowerSymbolOperand(MO, Printer.GetJTISymbol(MO.getIndex()),
109                                Subtarget);
110      break;
111    case MachineOperand::MO_ConstantPoolIndex:
112      MCOp = lowerSymbolOperand(MO, Printer.GetCPISymbol(MO.getIndex()),
113                                Subtarget);
114      break;
115    }
116
117    OutMI.addOperand(MCOp);
118  }
119}
120
121} // end of namespace llvm
122