lib/Target/Blackfin/AsmPrinter/BlackfinAsmPrinter.cpp

   1 //===-- BlackfinAsmPrinter.cpp - Blackfin 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 GAS-format BLACKFIN assembly language.
  12 //
  13 //===----------------------------------------------------------------------===//
  14
  15 #define DEBUG_TYPE "asm-printer"
  16 #include "Blackfin.h"
  17 #include "BlackfinInstrInfo.h"
  18 #include "llvm/Constants.h"
  19 #include "llvm/DerivedTypes.h"
  20 #include "llvm/Module.h"
  21 #include "llvm/CodeGen/AsmPrinter.h"
  22 #include "llvm/CodeGen/DwarfWriter.h"
  23 #include "llvm/CodeGen/MachineFunctionPass.h"
  24 #include "llvm/CodeGen/MachineConstantPool.h"
  25 #include "llvm/CodeGen/MachineInstr.h"
  26 #include "llvm/MC/MCStreamer.h"
  27 #include "llvm/MC/MCAsmInfo.h"
  28 #include "llvm/MC/MCSymbol.h"
  29 #include "llvm/Target/TargetData.h"
  30 #include "llvm/Target/TargetLoweringObjectFile.h"
  31 #include "llvm/Target/TargetRegistry.h"
  32 #include "llvm/Support/Mangler.h"
  33 #include "llvm/ADT/Statistic.h"
  34 #include "llvm/Support/FormattedStream.h"
  35
  36 using namespace llvm;
  37
  38 STATISTIC(EmittedInsts, "Number of machine instrs printed");
  39
  40 namespace {
  41   class VISIBILITY_HIDDEN BlackfinAsmPrinter : public AsmPrinter {
  42   public:
  43     BlackfinAsmPrinter(formatted_raw_ostream &O, TargetMachine &TM,
  44                        const MCAsmInfo *MAI, bool V)
  45       : AsmPrinter(O, TM, MAI, V) {}
  46
  47     virtual const char *getPassName() const {
  48       return "Blackfin Assembly Printer";
  49     }
  50
  51     void printOperand(const MachineInstr *MI, int opNum);
  52     void printMemoryOperand(const MachineInstr *MI, int opNum);
  53     void printInstruction(const MachineInstr *MI);  // autogenerated.
  54     static const char *getRegisterName(unsigned RegNo);
  55
  56     void emitLinkage(const std::string &n, GlobalValue::LinkageTypes l);
  57     bool runOnMachineFunction(MachineFunction &F);
  58     bool PrintAsmOperand(const MachineInstr *MI, unsigned OpNo,
  59                          unsigned AsmVariant, const char *ExtraCode);
  60     bool PrintAsmMemoryOperand(const MachineInstr *MI, unsigned OpNo,
  61                                unsigned AsmVariant, const char *ExtraCode);
  62     void PrintGlobalVariable(const GlobalVariable* GVar);
  63   };
  64 } // end of anonymous namespace
  65
  66 #include "BlackfinGenAsmWriter.inc"
  67
  68 extern "C" void LLVMInitializeBlackfinAsmPrinter() {
  69   RegisterAsmPrinter<BlackfinAsmPrinter> X(TheBlackfinTarget);
  70 }
  71
  72 void BlackfinAsmPrinter::emitLinkage(const std::string &name,
  73                                      GlobalValue::LinkageTypes l) {
  74   switch (l) {
  75   default: llvm_unreachable("Unknown linkage type!");
  76   case GlobalValue::InternalLinkage:  // Symbols default to internal.
  77   case GlobalValue::PrivateLinkage:
  78   case GlobalValue::LinkerPrivateLinkage:
  79     break;
  80   case GlobalValue::ExternalLinkage:
  81     O << MAI->getGlobalDirective() << name << "\n";
  82     break;
  83   case GlobalValue::LinkOnceAnyLinkage:
  84   case GlobalValue::LinkOnceODRLinkage:
  85   case GlobalValue::WeakAnyLinkage:
  86   case GlobalValue::WeakODRLinkage:
  87     O << MAI->getGlobalDirective() << name << "\n";
  88     O << MAI->getWeakDefDirective() << name << "\n";
  89     break;
  90   }
  91 }
  92
  93 void BlackfinAsmPrinter::PrintGlobalVariable(const GlobalVariable* GV) {
  94   const TargetData *TD = TM.getTargetData();
  95
  96   if (!GV->hasInitializer() || EmitSpecialLLVMGlobal(GV))
  97     return;
  98
  99   std::string name = Mang->getMangledName(GV);
 100   Constant *C = GV->getInitializer();
 101
 102   OutStreamer.SwitchSection(getObjFileLowering().SectionForGlobal(GV, Mang,
 103                                                                   TM));
 104   emitLinkage(name, GV->getLinkage());
 105   EmitAlignment(TD->getPreferredAlignmentLog(GV), GV);
 106   printVisibility(name, GV->getVisibility());
 107
 108   O << "\t.type " << name << ", STT_OBJECT\n";
 109   O << "\t.size " << name << ',' << TD->getTypeAllocSize(C->getType()) << '\n';
 110   O << name << ":\n";
 111   EmitGlobalConstant(C);
 112 }
 113
 114 /// runOnMachineFunction - This uses the printInstruction()
 115 /// method to print assembly for each instruction.
 116 ///
 117 bool BlackfinAsmPrinter::runOnMachineFunction(MachineFunction &MF) {
 118   SetupMachineFunction(MF);
 119   EmitConstantPool(MF.getConstantPool());
 120   EmitJumpTableInfo(MF.getJumpTableInfo(), MF);
 121
 122   const Function *F = MF.getFunction();
 123   OutStreamer.SwitchSection(getObjFileLowering().SectionForGlobal(F, Mang, TM));
 124   EmitAlignment(2, F);
 125   emitLinkage(CurrentFnName, F->getLinkage());
 126   printVisibility(CurrentFnName, F->getVisibility());
 127
 128   O << "\t.type\t" << CurrentFnName << ", STT_FUNC\n"
 129     << CurrentFnName << ":\n";
 130
 131   if (DW)
 132     DW->BeginFunction(&MF);
 133
 134   // Print out code for the function.
 135   for (MachineFunction::const_iterator I = MF.begin(), E = MF.end();
 136        I != E; ++I) {
 137     // Print a label for the basic block.
 138     if (!VerboseAsm && (I->pred_empty() || I->isOnlyReachableByFallthrough())) {
 139       // This is an entry block or a block that's only reachable via a
 140       // fallthrough edge. In non-VerboseAsm mode, don't print the label.
 141     } else {
 142       EmitBasicBlockStart(I);
 143       O << '\n';
 144     }
 145
 146     for (MachineBasicBlock::const_iterator II = I->begin(), E = I->end();
 147          II != E; ++II) {
 148       // Print the assembly for the instruction.
 149       processDebugLoc(II->getDebugLoc());
 150
 151       printInstruction(II);
 152       if (VerboseAsm && !II->getDebugLoc().isUnknown())
 153         EmitComments(*II);
 154       O << '\n';
 155
 156       ++EmittedInsts;
 157     }
 158   }
 159
 160   O << "\t.size " << CurrentFnName << ", .-" << CurrentFnName << "\n";
 161
 162   if (DW)
 163     DW->EndFunction(&MF);
 164
 165   return false;
 166 }
 167
 168 void BlackfinAsmPrinter::printOperand(const MachineInstr *MI, int opNum) {
 169   const MachineOperand &MO = MI->getOperand (opNum);
 170   switch (MO.getType()) {
 171   case MachineOperand::MO_Register:
 172     assert(TargetRegisterInfo::isPhysicalRegister(MO.getReg()) &&
 173            "Virtual registers should be already mapped!");
 174     O << getRegisterName(MO.getReg());
 175     break;
 176
 177   case MachineOperand::MO_Immediate:
 178     O << MO.getImm();
 179     break;
 180   case MachineOperand::MO_MachineBasicBlock:
 181     GetMBBSymbol(MO.getMBB()->getNumber())->print(O, MAI);
 182     return;
 183   case MachineOperand::MO_GlobalAddress:
 184     O << Mang->getMangledName(MO.getGlobal());
 185     printOffset(MO.getOffset());
 186     break;
 187   case MachineOperand::MO_ExternalSymbol:
 188     O << Mang->makeNameProper(MO.getSymbolName());
 189     break;
 190   case MachineOperand::MO_ConstantPoolIndex:
 191     O << MAI->getPrivateGlobalPrefix() << "CPI" << getFunctionNumber() << "_"
 192       << MO.getIndex();
 193     break;
 194   case MachineOperand::MO_JumpTableIndex:
 195     O << MAI->getPrivateGlobalPrefix() << "JTI" << getFunctionNumber()
 196       << '_' << MO.getIndex();
 197     break;
 198   default:
 199     llvm_unreachable("<unknown operand type>");
 200     break;
 201   }
 202 }
 203
 204 void BlackfinAsmPrinter::printMemoryOperand(const MachineInstr *MI, int opNum) {
 205   printOperand(MI, opNum);
 206
 207   if (MI->getOperand(opNum+1).isImm() && MI->getOperand(opNum+1).getImm() == 0)
 208     return;
 209
 210   O << " + ";
 211   printOperand(MI, opNum+1);
 212 }
 213
 214 /// PrintAsmOperand - Print out an operand for an inline asm expression.
 215 ///
 216 bool BlackfinAsmPrinter::PrintAsmOperand(const MachineInstr *MI,
 217                                          unsigned OpNo,
 218                                          unsigned AsmVariant,
 219                                          const char *ExtraCode) {
 220   if (ExtraCode && ExtraCode[0]) {
 221     if (ExtraCode[1] != 0) return true; // Unknown modifier.
 222
 223     switch (ExtraCode[0]) {
 224     default: return true;  // Unknown modifier.
 225     case 'r':
 226       break;
 227     }
 228   }
 229
 230   printOperand(MI, OpNo);
 231
 232   return false;
 233 }
 234
 235 bool BlackfinAsmPrinter::PrintAsmMemoryOperand(const MachineInstr *MI,
 236                                                unsigned OpNo,
 237                                                unsigned AsmVariant,
 238                                                const char *ExtraCode) {
 239   if (ExtraCode && ExtraCode[0])
 240     return true;  // Unknown modifier
 241
 242   O << '[';
 243   printOperand(MI, OpNo);
 244   O << ']';
 245
 246   return false;
 247 }