1//===-- MBlazeMCInstLower.cpp - Convert MBlaze MachineInstr to an MCInst---===//
2//
3//                     The LLVM Compiler Infrastructure
4//
5// This file is distributed under the University of Illinois Open Source
6// License. See LICENSE.TXT for details.
7//
8//===----------------------------------------------------------------------===//
9//
10// This file contains code to lower MBlaze MachineInstrs to their corresponding
11// MCInst records.
12//
13//===----------------------------------------------------------------------===//
14
15#include "MBlazeMCInstLower.h"
16#include "MBlazeInstrInfo.h"
17#include "llvm/Constants.h"
18#include "llvm/CodeGen/AsmPrinter.h"
19#include "llvm/CodeGen/MachineBasicBlock.h"
20#include "llvm/CodeGen/MachineInstr.h"
21#include "llvm/MC/MCAsmInfo.h"
22#include "llvm/MC/MCContext.h"
23#include "llvm/MC/MCExpr.h"
24#include "llvm/MC/MCInst.h"
25#include "llvm/Target/Mangler.h"
26#include "llvm/Support/Debug.h"
27#include "llvm/Support/raw_ostream.h"
28#include "llvm/Support/ErrorHandling.h"
29#include "llvm/ADT/SmallString.h"
30using namespace llvm;
31
32MCSymbol *MBlazeMCInstLower::
33GetGlobalAddressSymbol(const MachineOperand &MO) const {
34  switch (MO.getTargetFlags()) {
35  default: llvm_unreachable("Unknown target flag on GV operand");
36  case 0:  break;
37  }
38
39  return Printer.Mang->getSymbol(MO.getGlobal());
40}
41
42MCSymbol *MBlazeMCInstLower::
43GetExternalSymbolSymbol(const MachineOperand &MO) const {
44  switch (MO.getTargetFlags()) {
45  default: llvm_unreachable("Unknown target flag on GV operand");
46  case 0:  break;
47  }
48
49  return Printer.GetExternalSymbolSymbol(MO.getSymbolName());
50}
51
52MCSymbol *MBlazeMCInstLower::
53GetJumpTableSymbol(const MachineOperand &MO) const {
54  SmallString<256> Name;
55  raw_svector_ostream(Name) << Printer.MAI->getPrivateGlobalPrefix() << "JTI"
56                            << Printer.getFunctionNumber() << '_'
57                            << MO.getIndex();
58  switch (MO.getTargetFlags()) {
59  default: llvm_unreachable("Unknown target flag on GV operand");
60  case 0:  break;
61  }
62
63  // Create a symbol for the name.
64  return Ctx.GetOrCreateSymbol(Name.str());
65}
66
67MCSymbol *MBlazeMCInstLower::
68GetConstantPoolIndexSymbol(const MachineOperand &MO) const {
69  SmallString<256> Name;
70  raw_svector_ostream(Name) << Printer.MAI->getPrivateGlobalPrefix() << "CPI"
71                            << Printer.getFunctionNumber() << '_'
72                            << MO.getIndex();
73
74  switch (MO.getTargetFlags()) {
75  default:
76      llvm_unreachable("Unknown target flag on GV operand");
77
78  case 0: break;
79  }
80
81  // Create a symbol for the name.
82  return Ctx.GetOrCreateSymbol(Name.str());
83}
84
85MCSymbol *MBlazeMCInstLower::
86GetBlockAddressSymbol(const MachineOperand &MO) const {
87  switch (MO.getTargetFlags()) {
88  default: llvm_unreachable("Unknown target flag on GV operand");
89  case 0: break;
90  }
91
92  return Printer.GetBlockAddressSymbol(MO.getBlockAddress());
93}
94
95MCOperand MBlazeMCInstLower::
96LowerSymbolOperand(const MachineOperand &MO, MCSymbol *Sym) const {
97  // FIXME: We would like an efficient form for this, so we don't have to do a
98  // lot of extra uniquing.
99  const MCExpr *Expr = MCSymbolRefExpr::Create(Sym, Ctx);
100
101  switch (MO.getTargetFlags()) {
102  default:
103      llvm_unreachable("Unknown target flag on GV operand");
104
105  case 0: break;
106  }
107
108  if (!MO.isJTI() && MO.getOffset())
109    Expr = MCBinaryExpr::CreateAdd(Expr,
110                                   MCConstantExpr::Create(MO.getOffset(), Ctx),
111                                   Ctx);
112  return MCOperand::CreateExpr(Expr);
113}
114
115void MBlazeMCInstLower::Lower(const MachineInstr *MI, MCInst &OutMI) const {
116  OutMI.setOpcode(MI->getOpcode());
117
118  for (unsigned i = 0, e = MI->getNumOperands(); i != e; ++i) {
119    const MachineOperand &MO = MI->getOperand(i);
120
121    MCOperand MCOp;
122    switch (MO.getType()) {
123    default: llvm_unreachable("unknown operand type");
124    case MachineOperand::MO_Register:
125      // Ignore all implicit register operands.
126      if (MO.isImplicit()) continue;
127      MCOp = MCOperand::CreateReg(MO.getReg());
128      break;
129    case MachineOperand::MO_Immediate:
130      MCOp = MCOperand::CreateImm(MO.getImm());
131      break;
132    case MachineOperand::MO_MachineBasicBlock:
133      MCOp = MCOperand::CreateExpr(MCSymbolRefExpr::Create(
134                         MO.getMBB()->getSymbol(), Ctx));
135      break;
136    case MachineOperand::MO_GlobalAddress:
137      MCOp = LowerSymbolOperand(MO, GetGlobalAddressSymbol(MO));
138      break;
139    case MachineOperand::MO_ExternalSymbol:
140      MCOp = LowerSymbolOperand(MO, GetExternalSymbolSymbol(MO));
141      break;
142    case MachineOperand::MO_JumpTableIndex:
143      MCOp = LowerSymbolOperand(MO, GetJumpTableSymbol(MO));
144      break;
145    case MachineOperand::MO_ConstantPoolIndex:
146      MCOp = LowerSymbolOperand(MO, GetConstantPoolIndexSymbol(MO));
147      break;
148    case MachineOperand::MO_BlockAddress:
149      MCOp = LowerSymbolOperand(MO, GetBlockAddressSymbol(MO));
150      break;
151    case MachineOperand::MO_FPImmediate: {
152      bool ignored;
153      APFloat FVal = MO.getFPImm()->getValueAPF();
154      FVal.convert(APFloat::IEEEsingle, APFloat::rmTowardZero, &ignored);
155
156      APInt IVal = FVal.bitcastToAPInt();
157      uint64_t Val = *IVal.getRawData();
158      MCOp = MCOperand::CreateImm(Val);
159      break;
160    }
161    case MachineOperand::MO_RegisterMask:
162      continue;
163    }
164
165    OutMI.addOperand(MCOp);
166  }
167}
168