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