lib/Target/SystemZ/AsmPrinter/SystemZAsmPrinter.cpp

   1 //===-- SystemZAsmPrinter.cpp - SystemZ 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 SystemZ assembly language.
  12 //
  13 //===----------------------------------------------------------------------===//
  14
  15 #define DEBUG_TYPE "asm-printer"
  16 #include "SystemZ.h"
  17 #include "SystemZInstrInfo.h"
  18 #include "SystemZTargetMachine.h"
  19 #include "llvm/Constants.h"
  20 #include "llvm/DerivedTypes.h"
  21 #include "llvm/Module.h"
  22 #include "llvm/Assembly/Writer.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/MCAsmInfo.h"
  31 #include "llvm/MC/MCSymbol.h"
  32 #include "llvm/Target/TargetData.h"
  33 #include "llvm/Target/TargetLoweringObjectFile.h"
  34 #include "llvm/Target/TargetRegistry.h"
  35 #include "llvm/ADT/Statistic.h"
  36 #include "llvm/Support/Compiler.h"
  37 #include "llvm/Support/FormattedStream.h"
  38 #include "llvm/Support/Mangler.h"
  39
  40 using namespace llvm;
  41
  42 STATISTIC(EmittedInsts, "Number of machine instrs printed");
  43
  44 namespace {
  45   class VISIBILITY_HIDDEN SystemZAsmPrinter : public AsmPrinter {
  46   public:
  47     SystemZAsmPrinter(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 "SystemZ Assembly Printer";
  53     }
  54
  55     void printOperand(const MachineInstr *MI, int OpNum,
  56                       const char* Modifier = 0);
  57     void printPCRelImmOperand(const MachineInstr *MI, int OpNum);
  58     void printRIAddrOperand(const MachineInstr *MI, int OpNum,
  59                             const char* Modifier = 0);
  60     void printRRIAddrOperand(const MachineInstr *MI, int OpNum,
  61                              const char* Modifier = 0);
  62     void printS16ImmOperand(const MachineInstr *MI, int OpNum) {
  63       O << (int16_t)MI->getOperand(OpNum).getImm();
  64     }
  65     void printS32ImmOperand(const MachineInstr *MI, int OpNum) {
  66       O << (int32_t)MI->getOperand(OpNum).getImm();
  67     }
  68
  69     void printInstruction(const MachineInstr *MI);  // autogenerated.
  70     static const char *getRegisterName(unsigned RegNo);
  71
  72     void printMachineInstruction(const MachineInstr * MI);
  73
  74     void emitFunctionHeader(const MachineFunction &MF);
  75     bool runOnMachineFunction(MachineFunction &F);
  76     void PrintGlobalVariable(const GlobalVariable* GVar);
  77
  78     void getAnalysisUsage(AnalysisUsage &AU) const {
  79       AsmPrinter::getAnalysisUsage(AU);
  80       AU.setPreservesAll();
  81     }
  82   };
  83 } // end of anonymous namespace
  84
  85 #include "SystemZGenAsmWriter.inc"
  86
  87 void SystemZAsmPrinter::emitFunctionHeader(const MachineFunction &MF) {
  88   unsigned FnAlign = MF.getAlignment();
  89   const Function *F = MF.getFunction();
  90
  91   OutStreamer.SwitchSection(getObjFileLowering().SectionForGlobal(F, Mang, TM));
  92
  93   EmitAlignment(FnAlign, F);
  94
  95   switch (F->getLinkage()) {
  96   default: assert(0 && "Unknown linkage type!");
  97   case Function::InternalLinkage:  // Symbols default to internal.
  98   case Function::PrivateLinkage:
  99   case Function::LinkerPrivateLinkage:
 100     break;
 101   case Function::ExternalLinkage:
 102     O << "\t.globl\t" << CurrentFnName << '\n';
 103     break;
 104   case Function::LinkOnceAnyLinkage:
 105   case Function::LinkOnceODRLinkage:
 106   case Function::WeakAnyLinkage:
 107   case Function::WeakODRLinkage:
 108     O << "\t.weak\t" << CurrentFnName << '\n';
 109     break;
 110   }
 111
 112   printVisibility(CurrentFnName, F->getVisibility());
 113
 114   O << "\t.type\t" << CurrentFnName << ",@function\n"
 115     << CurrentFnName << ":\n";
 116 }
 117
 118 bool SystemZAsmPrinter::runOnMachineFunction(MachineFunction &MF) {
 119   SetupMachineFunction(MF);
 120   O << "\n\n";
 121
 122   // Print out constants referenced by the function
 123   EmitConstantPool(MF.getConstantPool());
 124
 125   // Print the 'header' of function
 126   emitFunctionHeader(MF);
 127
 128   // Print out code for the function.
 129   for (MachineFunction::const_iterator I = MF.begin(), E = MF.end();
 130        I != E; ++I) {
 131     // Print a label for the basic block.
 132     if (!VerboseAsm && (I->pred_empty() || I->isOnlyReachableByFallthrough())) {
 133       // This is an entry block or a block that's only reachable via a
 134       // fallthrough edge. In non-VerboseAsm mode, don't print the label.
 135     } else {
 136       EmitBasicBlockStart(I);
 137       O << '\n';
 138     }
 139
 140     for (MachineBasicBlock::const_iterator II = I->begin(), E = I->end();
 141          II != E; ++II)
 142       // Print the assembly for the instruction.
 143       printMachineInstruction(II);
 144   }
 145
 146   if (MAI->hasDotTypeDotSizeDirective())
 147     O << "\t.size\t" << CurrentFnName << ", .-" << CurrentFnName << '\n';
 148
 149   // Print out jump tables referenced by the function.
 150   EmitJumpTableInfo(MF.getJumpTableInfo(), MF);
 151
 152   // We didn't modify anything
 153   return false;
 154 }
 155
 156 void SystemZAsmPrinter::printMachineInstruction(const MachineInstr *MI) {
 157   ++EmittedInsts;
 158
 159   processDebugLoc(MI->getDebugLoc());
 160
 161   // Call the autogenerated instruction printer routines.
 162   printInstruction(MI);
 163
 164   if (VerboseAsm && !MI->getDebugLoc().isUnknown())
 165     EmitComments(*MI);
 166   O << '\n';
 167 }
 168
 169 void SystemZAsmPrinter::printPCRelImmOperand(const MachineInstr *MI, int OpNum){
 170   const MachineOperand &MO = MI->getOperand(OpNum);
 171   switch (MO.getType()) {
 172   case MachineOperand::MO_Immediate:
 173     O << MO.getImm();
 174     return;
 175   case MachineOperand::MO_MachineBasicBlock:
 176     GetMBBSymbol(MO.getMBB()->getNumber())->print(O, MAI);
 177     return;
 178   case MachineOperand::MO_GlobalAddress: {
 179     const GlobalValue *GV = MO.getGlobal();
 180     std::string Name = Mang->getMangledName(GV);
 181
 182     O << Name;
 183
 184     // Assemble calls via PLT for externally visible symbols if PIC.
 185     if (TM.getRelocationModel() == Reloc::PIC_ &&
 186         !GV->hasHiddenVisibility() && !GV->hasProtectedVisibility() &&
 187         !GV->hasLocalLinkage())
 188       O << "@PLT";
 189
 190     printOffset(MO.getOffset());
 191     return;
 192   }
 193   case MachineOperand::MO_ExternalSymbol: {
 194     std::string Name(MAI->getGlobalPrefix());
 195     Name += MO.getSymbolName();
 196     O << Name;
 197
 198     if (TM.getRelocationModel() == Reloc::PIC_)
 199       O << "@PLT";
 200
 201     return;
 202   }
 203   default:
 204     assert(0 && "Not implemented yet!");
 205   }
 206 }
 207
 208
 209 void SystemZAsmPrinter::printOperand(const MachineInstr *MI, int OpNum,
 210                                      const char* Modifier) {
 211   const MachineOperand &MO = MI->getOperand(OpNum);
 212   switch (MO.getType()) {
 213   case MachineOperand::MO_Register: {
 214     assert (TargetRegisterInfo::isPhysicalRegister(MO.getReg()) &&
 215             "Virtual registers should be already mapped!");
 216     unsigned Reg = MO.getReg();
 217     if (Modifier && strncmp(Modifier, "subreg", 6) == 0) {
 218       if (strncmp(Modifier + 7, "even", 4) == 0)
 219         Reg = TRI->getSubReg(Reg, SystemZ::SUBREG_EVEN);
 220       else if (strncmp(Modifier + 7, "odd", 3) == 0)
 221         Reg = TRI->getSubReg(Reg, SystemZ::SUBREG_ODD);
 222       else
 223         assert(0 && "Invalid subreg modifier");
 224     }
 225
 226     O << '%' << getRegisterName(Reg);
 227     return;
 228   }
 229   case MachineOperand::MO_Immediate:
 230     O << MO.getImm();
 231     return;
 232   case MachineOperand::MO_MachineBasicBlock:
 233     GetMBBSymbol(MO.getMBB()->getNumber())->print(O, MAI);
 234     return;
 235   case MachineOperand::MO_JumpTableIndex:
 236     O << MAI->getPrivateGlobalPrefix() << "JTI" << getFunctionNumber() << '_'
 237       << MO.getIndex();
 238
 239     return;
 240   case MachineOperand::MO_ConstantPoolIndex:
 241     O << MAI->getPrivateGlobalPrefix() << "CPI" << getFunctionNumber() << '_'
 242       << MO.getIndex();
 243
 244     printOffset(MO.getOffset());
 245     break;
 246   case MachineOperand::MO_GlobalAddress: {
 247     const GlobalValue *GV = MO.getGlobal();
 248     std::string Name = Mang->getMangledName(GV);
 249
 250     O << Name;
 251     break;
 252   }
 253   case MachineOperand::MO_ExternalSymbol: {
 254     std::string Name(MAI->getGlobalPrefix());
 255     Name += MO.getSymbolName();
 256     O << Name;
 257     break;
 258   }
 259   default:
 260     assert(0 && "Not implemented yet!");
 261   }
 262
 263   switch (MO.getTargetFlags()) {
 264   default:
 265     llvm_unreachable("Unknown target flag on GV operand");
 266   case SystemZII::MO_NO_FLAG:
 267     break;
 268   case SystemZII::MO_GOTENT:    O << "@GOTENT";    break;
 269   case SystemZII::MO_PLT:       O << "@PLT";       break;
 270   }
 271
 272   printOffset(MO.getOffset());
 273 }
 274
 275 void SystemZAsmPrinter::printRIAddrOperand(const MachineInstr *MI, int OpNum,
 276                                            const char* Modifier) {
 277   const MachineOperand &Base = MI->getOperand(OpNum);
 278
 279   // Print displacement operand.
 280   printOperand(MI, OpNum+1);
 281
 282   // Print base operand (if any)
 283   if (Base.getReg()) {
 284     O << '(';
 285     printOperand(MI, OpNum);
 286     O << ')';
 287   }
 288 }
 289
 290 void SystemZAsmPrinter::printRRIAddrOperand(const MachineInstr *MI, int OpNum,
 291                                             const char* Modifier) {
 292   const MachineOperand &Base = MI->getOperand(OpNum);
 293   const MachineOperand &Index = MI->getOperand(OpNum+2);
 294
 295   // Print displacement operand.
 296   printOperand(MI, OpNum+1);
 297
 298   // Print base operand (if any)
 299   if (Base.getReg()) {
 300     O << '(';
 301     printOperand(MI, OpNum);
 302     if (Index.getReg()) {
 303       O << ',';
 304       printOperand(MI, OpNum+2);
 305     }
 306     O << ')';
 307   } else
 308     assert(!Index.getReg() && "Should allocate base register first!");
 309 }
 310
 311 void SystemZAsmPrinter::PrintGlobalVariable(const GlobalVariable* GVar) {
 312   const TargetData *TD = TM.getTargetData();
 313
 314   if (!GVar->hasInitializer())
 315     return;   // External global require no code
 316
 317   // Check to see if this is a special global used by LLVM, if so, emit it.
 318   if (EmitSpecialLLVMGlobal(GVar))
 319     return;
 320
 321   std::string name = Mang->getMangledName(GVar);
 322   Constant *C = GVar->getInitializer();
 323   unsigned Size = TD->getTypeAllocSize(C->getType());
 324   unsigned Align = std::max(1U, TD->getPreferredAlignmentLog(GVar));
 325
 326   printVisibility(name, GVar->getVisibility());
 327
 328   O << "\t.type\t" << name << ",@object\n";
 329
 330   OutStreamer.SwitchSection(getObjFileLowering().SectionForGlobal(GVar, Mang,
 331                                                                   TM));
 332
 333   if (C->isNullValue() && !GVar->hasSection() &&
 334       !GVar->isThreadLocal() &&
 335       (GVar->hasLocalLinkage() || GVar->isWeakForLinker())) {
 336
 337     if (Size == 0) Size = 1;   // .comm Foo, 0 is undefined, avoid it.
 338
 339     if (GVar->hasLocalLinkage())
 340       O << "\t.local\t" << name << '\n';
 341
 342     O << MAI->getCOMMDirective()  << name << ',' << Size;
 343     if (MAI->getCOMMDirectiveTakesAlignment())
 344       O << ',' << (MAI->getAlignmentIsInBytes() ? (1 << Align) : Align);
 345
 346     if (VerboseAsm) {
 347       O << "\t\t" << MAI->getCommentString() << ' ';
 348       WriteAsOperand(O, GVar, /*PrintType=*/false, GVar->getParent());
 349     }
 350     O << '\n';
 351     return;
 352   }
 353
 354   switch (GVar->getLinkage()) {
 355   case GlobalValue::CommonLinkage:
 356   case GlobalValue::LinkOnceAnyLinkage:
 357   case GlobalValue::LinkOnceODRLinkage:
 358   case GlobalValue::WeakAnyLinkage:
 359   case GlobalValue::WeakODRLinkage:
 360     O << "\t.weak\t" << name << '\n';
 361     break;
 362   case GlobalValue::DLLExportLinkage:
 363   case GlobalValue::AppendingLinkage:
 364     // FIXME: appending linkage variables should go into a section of
 365     // their name or something.  For now, just emit them as external.
 366   case GlobalValue::ExternalLinkage:
 367     // If external or appending, declare as a global symbol
 368     O << "\t.globl " << name << '\n';
 369     // FALL THROUGH
 370   case GlobalValue::PrivateLinkage:
 371   case GlobalValue::LinkerPrivateLinkage:
 372   case GlobalValue::InternalLinkage:
 373      break;
 374   default:
 375     assert(0 && "Unknown linkage type!");
 376   }
 377
 378   // Use 16-bit alignment by default to simplify bunch of stuff
 379   EmitAlignment(Align, GVar, 1);
 380   O << name << ":";
 381   if (VerboseAsm) {
 382     O << "\t\t\t\t" << MAI->getCommentString() << ' ';
 383     WriteAsOperand(O, GVar, /*PrintType=*/false, GVar->getParent());
 384   }
 385   O << '\n';
 386   if (MAI->hasDotTypeDotSizeDirective())
 387     O << "\t.size\t" << name << ", " << Size << '\n';
 388
 389   EmitGlobalConstant(C);
 390 }
 391
 392 // Force static initialization.
 393 extern "C" void LLVMInitializeSystemZAsmPrinter() {
 394   RegisterAsmPrinter<SystemZAsmPrinter> X(TheSystemZTarget);
 395 }