MSP430AsmPrinter.cpp revision 192957d376923cefc993c1b5c04127c42f1008ec 
1//===-- MSP430AsmPrinter.cpp - MSP430 LLVM assembly writer ------------------===//
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 a printer that converts from our internal representation
11// of machine-dependent LLVM code to the MSP430 assembly language.
12//
13//===----------------------------------------------------------------------===//
14
15#define DEBUG_TYPE "asm-printer"
16#include "MSP430.h"
17#include "MSP430InstrInfo.h"
18#include "MSP430TargetMachine.h"
19#include "llvm/Constants.h"
20#include "llvm/DerivedTypes.h"
21#include "llvm/Module.h"
22#include "llvm/CodeGen/AsmPrinter.h"
23#include "llvm/CodeGen/DwarfWriter.h"
24#include "llvm/CodeGen/MachineModuleInfo.h"
25#include "llvm/CodeGen/MachineFunctionPass.h"
26#include "llvm/CodeGen/MachineConstantPool.h"
27#include "llvm/CodeGen/MachineInstr.h"
28#include "llvm/Target/TargetAsmInfo.h"
29#include "llvm/Target/TargetData.h"
30#include "llvm/ADT/Statistic.h"
31#include "llvm/Support/Compiler.h"
32#include "llvm/Support/Mangler.h"
33#include "llvm/Support/raw_ostream.h"
34#include "llvm/Support/ErrorHandling.h"
35
36using namespace llvm;
37
38STATISTIC(EmittedInsts, "Number of machine instrs printed");
39
40namespace {
41  class VISIBILITY_HIDDEN MSP430AsmPrinter : public AsmPrinter {
42  public:
43    MSP430AsmPrinter(raw_ostream &O, MSP430TargetMachine &TM,
44                     const TargetAsmInfo *TAI, bool V)
45      : AsmPrinter(O, TM, TAI, V) {}
46
47    virtual const char *getPassName() const {
48      return "MSP430 Assembly Printer";
49    }
50
51    void printOperand(const MachineInstr *MI, int OpNum,
52                      const char* Modifier = 0);
53    void printSrcMemOperand(const MachineInstr *MI, int OpNum,
54                            const char* Modifier = 0);
55    void printCCOperand(const MachineInstr *MI, int OpNum);
56    bool printInstruction(const MachineInstr *MI);  // autogenerated.
57    void printMachineInstruction(const MachineInstr * MI);
58
59    void emitFunctionHeader(const MachineFunction &MF);
60    bool runOnMachineFunction(MachineFunction &F);
61    bool doInitialization(Module &M);
62    bool doFinalization(Module &M);
63
64    void getAnalysisUsage(AnalysisUsage &AU) const {
65      AsmPrinter::getAnalysisUsage(AU);
66      AU.setPreservesAll();
67    }
68  };
69} // end of anonymous namespace
70
71#include "MSP430GenAsmWriter.inc"
72
73/// createMSP430CodePrinterPass - Returns a pass that prints the MSP430
74/// assembly code for a MachineFunction to the given output stream,
75/// using the given target machine description.  This should work
76/// regardless of whether the function is in SSA form.
77///
78FunctionPass *llvm::createMSP430CodePrinterPass(raw_ostream &o,
79                                                MSP430TargetMachine &tm,
80                                                bool verbose) {
81  return new MSP430AsmPrinter(o, tm, tm.getTargetAsmInfo(), verbose);
82}
83
84bool MSP430AsmPrinter::doInitialization(Module &M) {
85  Mang = new Mangler(M, "", TAI->getPrivateGlobalPrefix());
86  return false; // success
87}
88
89
90bool MSP430AsmPrinter::doFinalization(Module &M) {
91  return AsmPrinter::doFinalization(M);
92}
93
94void MSP430AsmPrinter::emitFunctionHeader(const MachineFunction &MF) {
95  const Function *F = MF.getFunction();
96
97  SwitchToSection(TAI->SectionForGlobal(F));
98
99  unsigned FnAlign = MF.getAlignment();
100  EmitAlignment(FnAlign, F);
101
102  switch (F->getLinkage()) {
103  default: LLVM_UNREACHABLE("Unknown linkage type!");
104  case Function::InternalLinkage:  // Symbols default to internal.
105  case Function::PrivateLinkage:
106    break;
107  case Function::ExternalLinkage:
108    O << "\t.globl\t" << CurrentFnName << '\n';
109    break;
110  case Function::LinkOnceAnyLinkage:
111  case Function::LinkOnceODRLinkage:
112  case Function::WeakAnyLinkage:
113  case Function::WeakODRLinkage:
114    O << "\t.weak\t" << CurrentFnName << '\n';
115    break;
116  }
117
118  printVisibility(CurrentFnName, F->getVisibility());
119
120  O << "\t.type\t" << CurrentFnName << ",@function\n"
121    << CurrentFnName << ":\n";
122}
123
124bool MSP430AsmPrinter::runOnMachineFunction(MachineFunction &MF) {
125  SetupMachineFunction(MF);
126  O << "\n\n";
127
128  // Print the 'header' of function
129  emitFunctionHeader(MF);
130
131  // Print out code for the function.
132  for (MachineFunction::const_iterator I = MF.begin(), E = MF.end();
133       I != E; ++I) {
134    // Print a label for the basic block.
135    if (!VerboseAsm && (I->pred_empty() || I->isOnlyReachableByFallthrough())) {
136      // This is an entry block or a block that's only reachable via a
137      // fallthrough edge. In non-VerboseAsm mode, don't print the label.
138    } else {
139      printBasicBlockLabel(I, true, true, VerboseAsm);
140      O << '\n';
141    }
142
143    for (MachineBasicBlock::const_iterator II = I->begin(), E = I->end();
144         II != E; ++II)
145      // Print the assembly for the instruction.
146      printMachineInstruction(II);
147  }
148
149  if (TAI->hasDotTypeDotSizeDirective())
150    O << "\t.size\t" << CurrentFnName << ", .-" << CurrentFnName << '\n';
151
152  O.flush();
153
154  // We didn't modify anything
155  return false;
156}
157
158void MSP430AsmPrinter::printMachineInstruction(const MachineInstr *MI) {
159  ++EmittedInsts;
160
161  // Call the autogenerated instruction printer routines.
162  if (printInstruction(MI))
163    return;
164
165  LLVM_UNREACHABLE("Should not happen");
166}
167
168void MSP430AsmPrinter::printOperand(const MachineInstr *MI, int OpNum,
169                                    const char* Modifier) {
170  const MachineOperand &MO = MI->getOperand(OpNum);
171  switch (MO.getType()) {
172  case MachineOperand::MO_Register:
173    assert (TargetRegisterInfo::isPhysicalRegister(MO.getReg()) &&
174            "Virtual registers should be already mapped!");
175    O << TM.getRegisterInfo()->get(MO.getReg()).AsmName;
176    return;
177  case MachineOperand::MO_Immediate:
178    if (!Modifier || strcmp(Modifier, "nohash"))
179      O << '#';
180    O << MO.getImm();
181    return;
182  case MachineOperand::MO_MachineBasicBlock:
183    printBasicBlockLabel(MO.getMBB());
184    return;
185  case MachineOperand::MO_GlobalAddress: {
186    bool isMemOp  = Modifier && !strcmp(Modifier, "mem");
187    bool isCallOp = Modifier && !strcmp(Modifier, "call");
188    std::string Name = Mang->getValueName(MO.getGlobal());
189    assert(MO.getOffset() == 0 && "No offsets allowed!");
190
191    if (isCallOp)
192      O << '#';
193    else if (isMemOp)
194      O << '&';
195
196    O << Name;
197
198    return;
199  }
200  case MachineOperand::MO_ExternalSymbol: {
201    bool isCallOp = Modifier && !strcmp(Modifier, "call");
202    std::string Name(TAI->getGlobalPrefix());
203    Name += MO.getSymbolName();
204    if (isCallOp)
205      O << '#';
206    O << Name;
207    return;
208  }
209  default:
210    LLVM_UNREACHABLE("Not implemented yet!");
211  }
212}
213
214void MSP430AsmPrinter::printSrcMemOperand(const MachineInstr *MI, int OpNum,
215                                          const char* Modifier) {
216  const MachineOperand &Base = MI->getOperand(OpNum);
217  const MachineOperand &Disp = MI->getOperand(OpNum+1);
218
219  if (Base.isGlobal())
220    printOperand(MI, OpNum, "mem");
221  else if (Disp.isImm() && !Base.getReg())
222    printOperand(MI, OpNum);
223  else if (Base.getReg()) {
224    if (Disp.getImm()) {
225      printOperand(MI, OpNum + 1, "nohash");
226      O << '(';
227      printOperand(MI, OpNum);
228      O << ')';
229    } else {
230      O << '@';
231      printOperand(MI, OpNum);
232    }
233  } else
234    LLVM_UNREACHABLE("Unsupported memory operand");
235}
236
237void MSP430AsmPrinter::printCCOperand(const MachineInstr *MI, int OpNum) {
238  unsigned CC = MI->getOperand(OpNum).getImm();
239
240  switch (CC) {
241  default:
242   LLVM_UNREACHABLE("Unsupported CC code");
243   break;
244  case MSP430::COND_E:
245   O << "eq";
246   break;
247  case MSP430::COND_NE:
248   O << "ne";
249   break;
250  case MSP430::COND_HS:
251   O << "hs";
252   break;
253  case MSP430::COND_LO:
254   O << "lo";
255   break;
256  case MSP430::COND_GE:
257   O << "ge";
258   break;
259  case MSP430::COND_L:
260   O << 'l';
261   break;
262  }
263}
264