lib/Target/XCore/XCoreAsmPrinter.cpp

   1 //===-- XCoreAsmPrinter.cpp - XCore 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 XAS-format XCore assembly language.
  12 //
  13 //===----------------------------------------------------------------------===//
  14
  15 #define DEBUG_TYPE "asm-printer"
  16 #include "XCore.h"
  17 #include "XCoreInstrInfo.h"
  18 #include "XCoreSubtarget.h"
  19 #include "XCoreTargetMachine.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/Target/TargetAsmInfo.h"
  30 #include "llvm/Target/TargetData.h"
  31 #include "llvm/Support/Mangler.h"
  32 #include "llvm/ADT/Statistic.h"
  33 #include "llvm/ADT/StringExtras.h"
  34 #include "llvm/Support/CommandLine.h"
  35 #include "llvm/Support/MathExtras.h"
  36 #include "llvm/Support/raw_ostream.h"
  37 #include <algorithm>
  38 #include <cctype>
  39 using namespace llvm;
  40
  41 STATISTIC(EmittedInsts, "Number of machine instrs printed");
  42
  43 static cl::opt<std::string> FileDirective("xcore-file-directive", cl::Optional,
  44   cl::desc("Output a file directive into the assembly file"),
  45   cl::Hidden,
  46   cl::value_desc("filename"),
  47   cl::init(""));
  48
  49 static cl::opt<unsigned> MaxThreads("xcore-max-threads", cl::Optional,
  50   cl::desc("Maximum number of threads (for emulation thread-local storage)"),
  51   cl::Hidden,
  52   cl::value_desc("number"),
  53   cl::init(8));
  54
  55 namespace {
  56   class VISIBILITY_HIDDEN XCoreAsmPrinter : public AsmPrinter {
  57     DwarfWriter *DW;
  58     const XCoreSubtarget &Subtarget;
  59   public:
  60     explicit XCoreAsmPrinter(raw_ostream &O, XCoreTargetMachine &TM,
  61                              const TargetAsmInfo *T, CodeGenOpt::Level OL,
  62                              bool V)
  63       : AsmPrinter(O, TM, T, OL, V), DW(0),
  64         Subtarget(*TM.getSubtargetImpl()) {}
  65
  66     virtual const char *getPassName() const {
  67       return "XCore Assembly Printer";
  68     }
  69
  70     void printMemOperand(const MachineInstr *MI, int opNum);
  71     void printOperand(const MachineInstr *MI, int opNum);
  72     bool PrintAsmOperand(const MachineInstr *MI, unsigned OpNo,
  73                         unsigned AsmVariant, const char *ExtraCode);
  74
  75     void emitFileDirective(const std::string &filename);
  76     void emitGlobalDirective(const std::string &name);
  77     void emitExternDirective(const std::string &name);
  78
  79     void emitArrayBound(const std::string &name, const GlobalVariable *GV);
  80     void emitGlobal(const GlobalVariable *GV);
  81
  82     void emitFunctionStart(MachineFunction &MF);
  83     void emitFunctionEnd(MachineFunction &MF);
  84
  85     bool printInstruction(const MachineInstr *MI);  // autogenerated.
  86     void printMachineInstruction(const MachineInstr *MI);
  87     bool runOnMachineFunction(MachineFunction &F);
  88     bool doInitialization(Module &M);
  89     bool doFinalization(Module &M);
  90
  91     void getAnalysisUsage(AnalysisUsage &AU) const {
  92       AsmPrinter::getAnalysisUsage(AU);
  93       AU.setPreservesAll();
  94       AU.addRequired<MachineModuleInfo>();
  95       AU.addRequired<DwarfWriter>();
  96     }
  97   };
  98 } // end of anonymous namespace
  99
 100 #include "XCoreGenAsmWriter.inc"
 101
 102 /// createXCoreCodePrinterPass - Returns a pass that prints the XCore
 103 /// assembly code for a MachineFunction to the given output stream,
 104 /// using the given target machine description.  This should work
 105 /// regardless of whether the function is in SSA form.
 106 ///
 107 FunctionPass *llvm::createXCoreCodePrinterPass(raw_ostream &o,
 108                                                XCoreTargetMachine &tm,
 109                                                CodeGenOpt::Level OptLevel,
 110                                                bool verbose) {
 111   return new XCoreAsmPrinter(o, tm, tm.getTargetAsmInfo(), OptLevel, verbose);
 112 }
 113
 114 // PrintEscapedString - Print each character of the specified string, escaping
 115 // it if it is not printable or if it is an escape char.
 116 static void PrintEscapedString(const std::string &Str, raw_ostream &Out) {
 117   for (unsigned i = 0, e = Str.size(); i != e; ++i) {
 118     unsigned char C = Str[i];
 119     if (isprint(C) && C != '"' && C != '\\') {
 120       Out << C;
 121     } else {
 122       Out << '\\'
 123           << (char) ((C/16  < 10) ? ( C/16 +'0') : ( C/16 -10+'A'))
 124           << (char)(((C&15) < 10) ? ((C&15)+'0') : ((C&15)-10+'A'));
 125     }
 126   }
 127 }
 128
 129 void XCoreAsmPrinter::
 130 emitFileDirective(const std::string &name)
 131 {
 132   O << "\t.file\t\"";
 133   PrintEscapedString(name, O);
 134   O << "\"\n";
 135 }
 136
 137 void XCoreAsmPrinter::
 138 emitGlobalDirective(const std::string &name)
 139 {
 140   O << TAI->getGlobalDirective() << name;
 141   O << "\n";
 142 }
 143
 144 void XCoreAsmPrinter::
 145 emitExternDirective(const std::string &name)
 146 {
 147   O << "\t.extern\t" << name;
 148   O << '\n';
 149 }
 150
 151 void XCoreAsmPrinter::
 152 emitArrayBound(const std::string &name, const GlobalVariable *GV)
 153 {
 154   assert(((GV->hasExternalLinkage() ||
 155     GV->hasWeakLinkage()) ||
 156     GV->hasLinkOnceLinkage()) && "Unexpected linkage");
 157   if (const ArrayType *ATy = dyn_cast<ArrayType>(
 158     cast<PointerType>(GV->getType())->getElementType()))
 159   {
 160     O << TAI->getGlobalDirective() << name << ".globound" << "\n";
 161     O << TAI->getSetDirective() << name << ".globound" << ","
 162       << ATy->getNumElements() << "\n";
 163     if (GV->hasWeakLinkage() || GV->hasLinkOnceLinkage()) {
 164       // TODO Use COMDAT groups for LinkOnceLinkage
 165       O << TAI->getWeakDefDirective() << name << ".globound" << "\n";
 166     }
 167   }
 168 }
 169
 170 void XCoreAsmPrinter::
 171 emitGlobal(const GlobalVariable *GV)
 172 {
 173   const TargetData *TD = TM.getTargetData();
 174
 175   if (GV->hasInitializer()) {
 176     // Check to see if this is a special global used by LLVM, if so, emit it.
 177     if (EmitSpecialLLVMGlobal(GV))
 178       return;
 179
 180     SwitchToSection(TAI->SectionForGlobal(GV));
 181
 182     std::string name = Mang->getValueName(GV);
 183     Constant *C = GV->getInitializer();
 184     unsigned Align = (unsigned)TD->getPreferredTypeAlignmentShift(C->getType());
 185
 186     // Mark the start of the global
 187     O << "\t.cc_top " << name << ".data," << name << "\n";
 188
 189     switch (GV->getLinkage()) {
 190     case GlobalValue::AppendingLinkage:
 191       cerr << "AppendingLinkage is not supported by this target!\n";
 192       abort();
 193     case GlobalValue::LinkOnceAnyLinkage:
 194     case GlobalValue::LinkOnceODRLinkage:
 195     case GlobalValue::WeakAnyLinkage:
 196     case GlobalValue::WeakODRLinkage:
 197     case GlobalValue::ExternalLinkage:
 198       emitArrayBound(name, GV);
 199       emitGlobalDirective(name);
 200       // TODO Use COMDAT groups for LinkOnceLinkage
 201       if (GV->hasWeakLinkage() || GV->hasLinkOnceLinkage()) {
 202         O << TAI->getWeakDefDirective() << name << "\n";
 203       }
 204       // FALL THROUGH
 205     case GlobalValue::InternalLinkage:
 206     case GlobalValue::PrivateLinkage:
 207       break;
 208     case GlobalValue::GhostLinkage:
 209       cerr << "Should not have any unmaterialized functions!\n";
 210       abort();
 211     case GlobalValue::DLLImportLinkage:
 212       cerr << "DLLImport linkage is not supported by this target!\n";
 213       abort();
 214     case GlobalValue::DLLExportLinkage:
 215       cerr << "DLLExport linkage is not supported by this target!\n";
 216       abort();
 217     default:
 218       assert(0 && "Unknown linkage type!");
 219     }
 220
 221     EmitAlignment(Align, GV, 2);
 222
 223     unsigned Size = TD->getTypeAllocSize(C->getType());
 224     if (GV->isThreadLocal()) {
 225       Size *= MaxThreads;
 226     }
 227     if (TAI->hasDotTypeDotSizeDirective()) {
 228       O << "\t.type " << name << ",@object\n";
 229       O << "\t.size " << name << "," << Size << "\n";
 230     }
 231     O << name << ":\n";
 232
 233     EmitGlobalConstant(C);
 234     if (GV->isThreadLocal()) {
 235       for (unsigned i = 1; i < MaxThreads; ++i) {
 236         EmitGlobalConstant(C);
 237       }
 238     }
 239     if (Size < 4) {
 240       // The ABI requires that unsigned scalar types smaller than 32 bits
 241       // are are padded to 32 bits.
 242       EmitZeros(4 - Size);
 243     }
 244
 245     // Mark the end of the global
 246     O << "\t.cc_bottom " << name << ".data\n";
 247   } else {
 248     if (GV->hasExternalWeakLinkage())
 249       ExtWeakSymbols.insert(GV);
 250   }
 251 }
 252
 253 /// Emit the directives on the start of functions
 254 void XCoreAsmPrinter::
 255 emitFunctionStart(MachineFunction &MF)
 256 {
 257   // Print out the label for the function.
 258   const Function *F = MF.getFunction();
 259
 260   SwitchToSection(TAI->SectionForGlobal(F));
 261
 262   // Mark the start of the function
 263   O << "\t.cc_top " << CurrentFnName << ".function," << CurrentFnName << "\n";
 264
 265   switch (F->getLinkage()) {
 266   default: assert(0 && "Unknown linkage type!");
 267   case Function::InternalLinkage:  // Symbols default to internal.
 268   case Function::PrivateLinkage:
 269     break;
 270   case Function::ExternalLinkage:
 271     emitGlobalDirective(CurrentFnName);
 272     break;
 273   case Function::LinkOnceAnyLinkage:
 274   case Function::LinkOnceODRLinkage:
 275   case Function::WeakAnyLinkage:
 276   case Function::WeakODRLinkage:
 277     // TODO Use COMDAT groups for LinkOnceLinkage
 278     O << TAI->getGlobalDirective() << CurrentFnName << "\n";
 279     O << TAI->getWeakDefDirective() << CurrentFnName << "\n";
 280     break;
 281   }
 282   // (1 << 1) byte aligned
 283   EmitAlignment(1, F, 1);
 284   if (TAI->hasDotTypeDotSizeDirective()) {
 285     O << "\t.type " << CurrentFnName << ",@function\n";
 286   }
 287   O << CurrentFnName << ":\n";
 288 }
 289
 290 /// Emit the directives on the end of functions
 291 void XCoreAsmPrinter::
 292 emitFunctionEnd(MachineFunction &MF)
 293 {
 294   // Mark the end of the function
 295   O << "\t.cc_bottom " << CurrentFnName << ".function\n";
 296 }
 297
 298 /// runOnMachineFunction - This uses the printMachineInstruction()
 299 /// method to print assembly for each instruction.
 300 ///
 301 bool XCoreAsmPrinter::runOnMachineFunction(MachineFunction &MF)
 302 {
 303   this->MF = &MF;
 304
 305   SetupMachineFunction(MF);
 306
 307   // Print out constants referenced by the function
 308   EmitConstantPool(MF.getConstantPool());
 309
 310   // Print out jump tables referenced by the function
 311   EmitJumpTableInfo(MF.getJumpTableInfo(), MF);
 312
 313   // Emit the function start directives
 314   emitFunctionStart(MF);
 315
 316   // Emit pre-function debug information.
 317   DW->BeginFunction(&MF);
 318
 319   // Print out code for the function.
 320   for (MachineFunction::const_iterator I = MF.begin(), E = MF.end();
 321        I != E; ++I) {
 322
 323     // Print a label for the basic block.
 324     if (I != MF.begin()) {
 325       printBasicBlockLabel(I, true , true);
 326       O << '\n';
 327     }
 328
 329     for (MachineBasicBlock::const_iterator II = I->begin(), E = I->end();
 330          II != E; ++II) {
 331       // Print the assembly for the instruction.
 332       O << "\t";
 333       printMachineInstruction(II);
 334     }
 335
 336     // Each Basic Block is separated by a newline
 337     O << '\n';
 338   }
 339
 340   // Emit function end directives
 341   emitFunctionEnd(MF);
 342
 343   // Emit post-function debug information.
 344   DW->EndFunction(&MF);
 345
 346   // We didn't modify anything.
 347   return false;
 348 }
 349
 350 void XCoreAsmPrinter::printMemOperand(const MachineInstr *MI, int opNum)
 351 {
 352   printOperand(MI, opNum);
 353
 354   if (MI->getOperand(opNum+1).isImm()
 355     && MI->getOperand(opNum+1).getImm() == 0)
 356     return;
 357
 358   O << "+";
 359   printOperand(MI, opNum+1);
 360 }
 361
 362 void XCoreAsmPrinter::printOperand(const MachineInstr *MI, int opNum) {
 363   const MachineOperand &MO = MI->getOperand(opNum);
 364   switch (MO.getType()) {
 365   case MachineOperand::MO_Register:
 366     if (TargetRegisterInfo::isPhysicalRegister(MO.getReg()))
 367       O << TM.getRegisterInfo()->get(MO.getReg()).AsmName;
 368     else
 369       assert(0 && "not implemented");
 370     break;
 371   case MachineOperand::MO_Immediate:
 372     O << MO.getImm();
 373     break;
 374   case MachineOperand::MO_MachineBasicBlock:
 375     printBasicBlockLabel(MO.getMBB());
 376     break;
 377   case MachineOperand::MO_GlobalAddress:
 378     {
 379       const GlobalValue *GV = MO.getGlobal();
 380       O << Mang->getValueName(GV);
 381       if (GV->hasExternalWeakLinkage())
 382         ExtWeakSymbols.insert(GV);
 383     }
 384     break;
 385   case MachineOperand::MO_ExternalSymbol:
 386     O << MO.getSymbolName();
 387     break;
 388   case MachineOperand::MO_ConstantPoolIndex:
 389     O << TAI->getPrivateGlobalPrefix() << "CPI" << getFunctionNumber()
 390       << '_' << MO.getIndex();
 391     break;
 392   case MachineOperand::MO_JumpTableIndex:
 393     O << TAI->getPrivateGlobalPrefix() << "JTI" << getFunctionNumber()
 394       << '_' << MO.getIndex();
 395     break;
 396   default:
 397     assert(0 && "not implemented");
 398   }
 399 }
 400
 401 /// PrintAsmOperand - Print out an operand for an inline asm expression.
 402 ///
 403 bool XCoreAsmPrinter::PrintAsmOperand(const MachineInstr *MI, unsigned OpNo,
 404                                       unsigned AsmVariant,
 405                                       const char *ExtraCode) {
 406   printOperand(MI, OpNo);
 407   return false;
 408 }
 409
 410 void XCoreAsmPrinter::printMachineInstruction(const MachineInstr *MI) {
 411   ++EmittedInsts;
 412
 413   // Check for mov mnemonic
 414   unsigned src, dst, srcSR, dstSR;
 415   if (TM.getInstrInfo()->isMoveInstr(*MI, src, dst, srcSR, dstSR)) {
 416     O << "\tmov ";
 417     O << TM.getRegisterInfo()->get(dst).AsmName;
 418     O << ", ";
 419     O << TM.getRegisterInfo()->get(src).AsmName;
 420     O << "\n";
 421     return;
 422   }
 423   if (printInstruction(MI)) {
 424     return;
 425   }
 426   assert(0 && "Unhandled instruction in asm writer!");
 427 }
 428
 429 bool XCoreAsmPrinter::doInitialization(Module &M) {
 430   bool Result = AsmPrinter::doInitialization(M);
 431
 432   if (!FileDirective.empty()) {
 433     emitFileDirective(FileDirective);
 434   }
 435
 436   // Print out type strings for external functions here
 437   for (Module::const_iterator I = M.begin(), E = M.end();
 438        I != E; ++I) {
 439     if (I->isDeclaration() && !I->isIntrinsic()) {
 440       switch (I->getLinkage()) {
 441       default:
 442         assert(0 && "Unexpected linkage");
 443       case Function::ExternalWeakLinkage:
 444         ExtWeakSymbols.insert(I);
 445         // fallthrough
 446       case Function::ExternalLinkage:
 447         break;
 448       }
 449     }
 450   }
 451
 452   // Emit initial debug information.
 453   DW = getAnalysisIfAvailable<DwarfWriter>();
 454   assert(DW && "Dwarf Writer is not available");
 455   DW->BeginModule(&M, getAnalysisIfAvailable<MachineModuleInfo>(),
 456                   O, this, TAI);
 457   return Result;
 458 }
 459
 460 bool XCoreAsmPrinter::doFinalization(Module &M) {
 461
 462   // Print out module-level global variables.
 463   for (Module::const_global_iterator I = M.global_begin(), E = M.global_end();
 464        I != E; ++I) {
 465     emitGlobal(I);
 466   }
 467
 468   // Emit final debug information.
 469   DW->EndModule();
 470
 471   return AsmPrinter::doFinalization(M);
 472 }