lib/Target/MSP430/AsmPrinter/MSP430AsmPrinter.cpp

   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 "MSP430MCAsmInfo.h"
  19 #include "MSP430TargetMachine.h"
  20 #include "llvm/Constants.h"
  21 #include "llvm/DerivedTypes.h"
  22 #include "llvm/Module.h"
  23 #include "llvm/CodeGen/AsmPrinter.h"
  24 #include "llvm/CodeGen/DwarfWriter.h"
  25 #include "llvm/CodeGen/MachineModuleInfo.h"
  26 #include "llvm/CodeGen/MachineFunctionPass.h"
  27 #include "llvm/CodeGen/MachineConstantPool.h"
  28 #include "llvm/CodeGen/MachineInstr.h"
  29 #include "llvm/MC/MCStreamer.h"
  30 #include "llvm/MC/MCSymbol.h"
  31 #include "llvm/Target/TargetData.h"
  32 #include "llvm/Target/TargetLoweringObjectFile.h"
  33 #include "llvm/Target/TargetRegistry.h"
  34 #include "llvm/ADT/Statistic.h"
  35 #include "llvm/Support/Compiler.h"
  36 #include "llvm/Support/FormattedStream.h"
  37 #include "llvm/Support/Mangler.h"
  38 #include "llvm/Support/ErrorHandling.h"
  39
  40 using namespace llvm;
  41
  42 STATISTIC(EmittedInsts, "Number of machine instrs printed");
  43
  44 namespace {
  45   class VISIBILITY_HIDDEN MSP430AsmPrinter : public AsmPrinter {
  46   public:
  47     MSP430AsmPrinter(formatted_raw_ostream &O, TargetMachine &TM,
  48                      const MCAsmInfo *MAI, bool V)
  49       : AsmPrinter(O, TM, MAI, V) {}
  50
  51     virtual const char *getPassName() const {
  52       return "MSP430 Assembly Printer";
  53     }
  54
  55     void printOperand(const MachineInstr *MI, int OpNum,
  56                       const char* Modifier = 0);
  57     void printSrcMemOperand(const MachineInstr *MI, int OpNum,
  58                             const char* Modifier = 0);
  59     void printCCOperand(const MachineInstr *MI, int OpNum);
  60     void printInstruction(const MachineInstr *MI);  // autogenerated.
  61     static const char *getRegisterName(unsigned RegNo);
  62
  63     void printMachineInstruction(const MachineInstr * MI);
  64     bool PrintAsmOperand(const MachineInstr *MI, unsigned OpNo,
  65                          unsigned AsmVariant,
  66                          const char *ExtraCode);
  67
  68     void emitFunctionHeader(const MachineFunction &MF);
  69     bool runOnMachineFunction(MachineFunction &F);
  70
  71     virtual void PrintGlobalVariable(const GlobalVariable *GV) {
  72       // FIXME: No support for global variables?
  73     }
  74
  75     void getAnalysisUsage(AnalysisUsage &AU) const {
  76       AsmPrinter::getAnalysisUsage(AU);
  77       AU.setPreservesAll();
  78     }
  79   };
  80 } // end of anonymous namespace
  81
  82 #include "MSP430GenAsmWriter.inc"
  83
  84
  85 void MSP430AsmPrinter::emitFunctionHeader(const MachineFunction &MF) {
  86   const Function *F = MF.getFunction();
  87
  88   OutStreamer.SwitchSection(getObjFileLowering().SectionForGlobal(F, Mang, TM));
  89
  90   unsigned FnAlign = MF.getAlignment();
  91   EmitAlignment(FnAlign, F);
  92
  93   switch (F->getLinkage()) {
  94   default: llvm_unreachable("Unknown linkage type!");
  95   case Function::InternalLinkage:  // Symbols default to internal.
  96   case Function::PrivateLinkage:
  97   case Function::LinkerPrivateLinkage:
  98     break;
  99   case Function::ExternalLinkage:
 100     O << "\t.globl\t" << CurrentFnName << '\n';
 101     break;
 102   case Function::LinkOnceAnyLinkage:
 103   case Function::LinkOnceODRLinkage:
 104   case Function::WeakAnyLinkage:
 105   case Function::WeakODRLinkage:
 106     O << "\t.weak\t" << CurrentFnName << '\n';
 107     break;
 108   }
 109
 110   printVisibility(CurrentFnName, F->getVisibility());
 111
 112   O << "\t.type\t" << CurrentFnName << ",@function\n"
 113     << CurrentFnName << ":\n";
 114 }
 115
 116 bool MSP430AsmPrinter::runOnMachineFunction(MachineFunction &MF) {
 117   SetupMachineFunction(MF);
 118   O << "\n\n";
 119
 120   // Print the 'header' of function
 121   emitFunctionHeader(MF);
 122
 123   // Print out code for the function.
 124   for (MachineFunction::const_iterator I = MF.begin(), E = MF.end();
 125        I != E; ++I) {
 126     // Print a label for the basic block.
 127     if (!VerboseAsm && (I->pred_empty() || I->isOnlyReachableByFallthrough())) {
 128       // This is an entry block or a block that's only reachable via a
 129       // fallthrough edge. In non-VerboseAsm mode, don't print the label.
 130     } else {
 131       EmitBasicBlockStart(I);
 132       O << '\n';
 133     }
 134
 135     for (MachineBasicBlock::const_iterator II = I->begin(), E = I->end();
 136          II != E; ++II)
 137       // Print the assembly for the instruction.
 138       printMachineInstruction(II);
 139   }
 140
 141   if (MAI->hasDotTypeDotSizeDirective())
 142     O << "\t.size\t" << CurrentFnName << ", .-" << CurrentFnName << '\n';
 143
 144   // We didn't modify anything
 145   return false;
 146 }
 147
 148 void MSP430AsmPrinter::printMachineInstruction(const MachineInstr *MI) {
 149   ++EmittedInsts;
 150
 151   processDebugLoc(MI->getDebugLoc());
 152
 153   // Call the autogenerated instruction printer routines.
 154   printInstruction(MI);
 155
 156   if (VerboseAsm && !MI->getDebugLoc().isUnknown())
 157     EmitComments(*MI);
 158   O << '\n';
 159 }
 160
 161 void MSP430AsmPrinter::printOperand(const MachineInstr *MI, int OpNum,
 162                                     const char* Modifier) {
 163   const MachineOperand &MO = MI->getOperand(OpNum);
 164   switch (MO.getType()) {
 165   case MachineOperand::MO_Register:
 166     O << getRegisterName(MO.getReg());
 167     return;
 168   case MachineOperand::MO_Immediate:
 169     if (!Modifier || strcmp(Modifier, "nohash"))
 170       O << '#';
 171     O << MO.getImm();
 172     return;
 173   case MachineOperand::MO_MachineBasicBlock:
 174     GetMBBSymbol(MO.getMBB()->getNumber())->print(O, MAI);
 175     return;
 176   case MachineOperand::MO_GlobalAddress: {
 177     bool isMemOp  = Modifier && !strcmp(Modifier, "mem");
 178     bool isCallOp = Modifier && !strcmp(Modifier, "call");
 179     std::string Name = Mang->getMangledName(MO.getGlobal());
 180     assert(MO.getOffset() == 0 && "No offsets allowed!");
 181
 182     if (isCallOp)
 183       O << '#';
 184     else if (isMemOp)
 185       O << '&';
 186
 187     O << Name;
 188
 189     return;
 190   }
 191   case MachineOperand::MO_ExternalSymbol: {
 192     bool isCallOp = Modifier && !strcmp(Modifier, "call");
 193     std::string Name(MAI->getGlobalPrefix());
 194     Name += MO.getSymbolName();
 195     if (isCallOp)
 196       O << '#';
 197     O << Name;
 198     return;
 199   }
 200   default:
 201     llvm_unreachable("Not implemented yet!");
 202   }
 203 }
 204
 205 void MSP430AsmPrinter::printSrcMemOperand(const MachineInstr *MI, int OpNum,
 206                                           const char* Modifier) {
 207   const MachineOperand &Base = MI->getOperand(OpNum);
 208   const MachineOperand &Disp = MI->getOperand(OpNum+1);
 209
 210   if (Base.isGlobal())
 211     printOperand(MI, OpNum, "mem");
 212   else if (Disp.isImm() && !Base.getReg())
 213     printOperand(MI, OpNum);
 214   else if (Base.getReg()) {
 215     if (Disp.getImm()) {
 216       printOperand(MI, OpNum + 1, "nohash");
 217       O << '(';
 218       printOperand(MI, OpNum);
 219       O << ')';
 220     } else {
 221       O << '@';
 222       printOperand(MI, OpNum);
 223     }
 224   } else
 225     llvm_unreachable("Unsupported memory operand");
 226 }
 227
 228 void MSP430AsmPrinter::printCCOperand(const MachineInstr *MI, int OpNum) {
 229   unsigned CC = MI->getOperand(OpNum).getImm();
 230
 231   switch (CC) {
 232   default:
 233    llvm_unreachable("Unsupported CC code");
 234    break;
 235   case MSP430::COND_E:
 236    O << "eq";
 237    break;
 238   case MSP430::COND_NE:
 239    O << "ne";
 240    break;
 241   case MSP430::COND_HS:
 242    O << "hs";
 243    break;
 244   case MSP430::COND_LO:
 245    O << "lo";
 246    break;
 247   case MSP430::COND_GE:
 248    O << "ge";
 249    break;
 250   case MSP430::COND_L:
 251    O << 'l';
 252    break;
 253   }
 254 }
 255
 256 /// PrintAsmOperand - Print out an operand for an inline asm expression.
 257 ///
 258 bool MSP430AsmPrinter::PrintAsmOperand(const MachineInstr *MI, unsigned OpNo,
 259                                        unsigned AsmVariant,
 260                                        const char *ExtraCode) {
 261   // Does this asm operand have a single letter operand modifier?
 262   if (ExtraCode && ExtraCode[0])
 263     return true; // Unknown modifier.
 264
 265   printOperand(MI, OpNo);
 266   return false;
 267 }
 268
 269 // Force static initialization.
 270 extern "C" void LLVMInitializeMSP430AsmPrinter() {
 271   RegisterAsmPrinter<MSP430AsmPrinter> X(TheMSP430Target);
 272 }