1//===-- MSP430MCInstLower.cpp - Convert MSP430 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 MSP430 MachineInstrs to their corresponding
11// MCInst records.
12//
13//===----------------------------------------------------------------------===//
14
15#include "MSP430MCInstLower.h"
16#include "llvm/ADT/SmallString.h"
17#include "llvm/CodeGen/AsmPrinter.h"
18#include "llvm/CodeGen/MachineBasicBlock.h"
19#include "llvm/CodeGen/MachineInstr.h"
20#include "llvm/IR/DataLayout.h"
21#include "llvm/IR/Mangler.h"
22#include "llvm/MC/MCAsmInfo.h"
23#include "llvm/MC/MCContext.h"
24#include "llvm/MC/MCExpr.h"
25#include "llvm/MC/MCInst.h"
26#include "llvm/Support/ErrorHandling.h"
27#include "llvm/Support/raw_ostream.h"
28#include "llvm/Target/TargetMachine.h"
29using namespace llvm;
30
31MCSymbol *MSP430MCInstLower::
32GetGlobalAddressSymbol(const MachineOperand &MO) const {
33  switch (MO.getTargetFlags()) {
34  default: llvm_unreachable("Unknown target flag on GV operand");
35  case 0: break;
36  }
37
38  return Printer.getSymbol(MO.getGlobal());
39}
40
41MCSymbol *MSP430MCInstLower::
42GetExternalSymbolSymbol(const MachineOperand &MO) const {
43  switch (MO.getTargetFlags()) {
44  default: llvm_unreachable("Unknown target flag on GV operand");
45  case 0: break;
46  }
47
48  return Printer.GetExternalSymbolSymbol(MO.getSymbolName());
49}
50
51MCSymbol *MSP430MCInstLower::
52GetJumpTableSymbol(const MachineOperand &MO) const {
53  const DataLayout *DL = Printer.TM.getDataLayout();
54  SmallString<256> Name;
55  raw_svector_ostream(Name) << DL->getPrivateGlobalPrefix() << "JTI"
56                            << Printer.getFunctionNumber() << '_'
57                            << MO.getIndex();
58
59  switch (MO.getTargetFlags()) {
60  default: llvm_unreachable("Unknown target flag on GV operand");
61  case 0: break;
62  }
63
64  // Create a symbol for the name.
65  return Ctx.GetOrCreateSymbol(Name.str());
66}
67
68MCSymbol *MSP430MCInstLower::
69GetConstantPoolIndexSymbol(const MachineOperand &MO) const {
70  const DataLayout *DL = Printer.TM.getDataLayout();
71  SmallString<256> Name;
72  raw_svector_ostream(Name) << DL->getPrivateGlobalPrefix() << "CPI"
73                            << Printer.getFunctionNumber() << '_'
74                            << MO.getIndex();
75
76  switch (MO.getTargetFlags()) {
77  default: llvm_unreachable("Unknown target flag on GV operand");
78  case 0: break;
79  }
80
81  // Create a symbol for the name.
82  return Ctx.GetOrCreateSymbol(Name.str());
83}
84
85MCSymbol *MSP430MCInstLower::
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 MSP430MCInstLower::
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: llvm_unreachable("Unknown target flag on GV operand");
103  case 0: break;
104  }
105
106  if (!MO.isJTI() && MO.getOffset())
107    Expr = MCBinaryExpr::CreateAdd(Expr,
108                                   MCConstantExpr::Create(MO.getOffset(), Ctx),
109                                   Ctx);
110  return MCOperand::CreateExpr(Expr);
111}
112
113void MSP430MCInstLower::Lower(const MachineInstr *MI, MCInst &OutMI) const {
114  OutMI.setOpcode(MI->getOpcode());
115
116  for (unsigned i = 0, e = MI->getNumOperands(); i != e; ++i) {
117    const MachineOperand &MO = MI->getOperand(i);
118
119    MCOperand MCOp;
120    switch (MO.getType()) {
121    default:
122      MI->dump();
123      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_RegisterMask:
152      continue;
153    }
154
155    OutMI.addOperand(MCOp);
156  }
157}
158