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