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/Target/TargetLoweringObjectFile.h"
  32 #include "llvm/Target/TargetRegistry.h"
  33 #include "llvm/Support/Mangler.h"
  34 #include "llvm/ADT/Statistic.h"
  35 #include "llvm/ADT/StringExtras.h"
  36 #include "llvm/Support/CommandLine.h"
  37 #include "llvm/Support/ErrorHandling.h"
  38 #include "llvm/Support/FormattedStream.h"
  39 #include "llvm/Support/MathExtras.h"
  40 #include <algorithm>
  41 #include <cctype>
  42 using namespace llvm;
  43
  44 STATISTIC(EmittedInsts, "Number of machine instrs printed");
  45
  46 static cl::opt<unsigned> MaxThreads("xcore-max-threads", cl::Optional,
  47   cl::desc("Maximum number of threads (for emulation thread-local storage)"),
  48   cl::Hidden,
  49   cl::value_desc("number"),
  50   cl::init(8));
  51
  52 namespace {
  53   class VISIBILITY_HIDDEN XCoreAsmPrinter : public AsmPrinter {
  54     DwarfWriter *DW;
  55     const XCoreSubtarget &Subtarget;
  56   public:
  57     explicit XCoreAsmPrinter(formatted_raw_ostream &O, TargetMachine &TM,
  58                              const TargetAsmInfo *T, bool V)
  59       : AsmPrinter(O, TM, T, V), DW(0),
  60       Subtarget(TM.getSubtarget<XCoreSubtarget>()) {}
  61
  62     virtual const char *getPassName() const {
  63       return "XCore Assembly Printer";
  64     }
  65
  66     void printMemOperand(const MachineInstr *MI, int opNum);
  67     void printOperand(const MachineInstr *MI, int opNum);
  68     bool PrintAsmOperand(const MachineInstr *MI, unsigned OpNo,
  69                         unsigned AsmVariant, const char *ExtraCode);
  70
  71     void emitGlobalDirective(const std::string &name);
  72     void emitExternDirective(const std::string &name);
  73
  74     void emitArrayBound(const std::string &name, const GlobalVariable *GV);
  75     virtual void PrintGlobalVariable(const GlobalVariable *GV);
  76
  77     void emitFunctionStart(MachineFunction &MF);
  78     void emitFunctionEnd(MachineFunction &MF);
  79
  80     bool printInstruction(const MachineInstr *MI);  // autogenerated.
  81     void printMachineInstruction(const MachineInstr *MI);
  82     bool runOnMachineFunction(MachineFunction &F);
  83     bool doInitialization(Module &M);
  84
  85     void getAnalysisUsage(AnalysisUsage &AU) const {
  86       AsmPrinter::getAnalysisUsage(AU);
  87       AU.setPreservesAll();
  88       AU.addRequired<MachineModuleInfo>();
  89       AU.addRequired<DwarfWriter>();
  90     }
  91   };
  92 } // end of anonymous namespace
  93
  94 #include "XCoreGenAsmWriter.inc"
  95
  96 void XCoreAsmPrinter::
  97 emitGlobalDirective(const std::string &name)
  98 {
  99   O << TAI->getGlobalDirective() << name;
 100   O << "\n";
 101 }
 102
 103 void XCoreAsmPrinter::
 104 emitExternDirective(const std::string &name)
 105 {
 106   O << "\t.extern\t" << name;
 107   O << '\n';
 108 }
 109
 110 void XCoreAsmPrinter::
 111 emitArrayBound(const std::string &name, const GlobalVariable *GV)
 112 {
 113   assert(((GV->hasExternalLinkage() ||
 114     GV->hasWeakLinkage()) ||
 115     GV->hasLinkOnceLinkage()) && "Unexpected linkage");
 116   if (const ArrayType *ATy = dyn_cast<ArrayType>(
 117     cast<PointerType>(GV->getType())->getElementType()))
 118   {
 119     O << TAI->getGlobalDirective() << name << ".globound" << "\n";
 120     O << TAI->getSetDirective() << name << ".globound" << ","
 121       << ATy->getNumElements() << "\n";
 122     if (GV->hasWeakLinkage() || GV->hasLinkOnceLinkage()) {
 123       // TODO Use COMDAT groups for LinkOnceLinkage
 124       O << TAI->getWeakDefDirective() << name << ".globound" << "\n";
 125     }
 126   }
 127 }
 128
 129 void XCoreAsmPrinter::PrintGlobalVariable(const GlobalVariable *GV) {
 130   // Check to see if this is a special global used by LLVM, if so, emit it.
 131   if (!GV->hasInitializer() ||
 132       EmitSpecialLLVMGlobal(GV))
 133     return;
 134
 135   const TargetData *TD = TM.getTargetData();
 136
 137   SwitchToSection(getObjFileLowering().SectionForGlobal(GV, Mang, TM));
 138
 139   std::string name = Mang->getMangledName(GV);
 140   Constant *C = GV->getInitializer();
 141   unsigned Align = (unsigned)TD->getPreferredTypeAlignmentShift(C->getType());
 142
 143   // Mark the start of the global
 144   O << "\t.cc_top " << name << ".data," << name << "\n";
 145
 146   switch (GV->getLinkage()) {
 147   case GlobalValue::AppendingLinkage:
 148     llvm_report_error("AppendingLinkage is not supported by this target!");
 149   case GlobalValue::LinkOnceAnyLinkage:
 150   case GlobalValue::LinkOnceODRLinkage:
 151   case GlobalValue::WeakAnyLinkage:
 152   case GlobalValue::WeakODRLinkage:
 153   case GlobalValue::ExternalLinkage:
 154     emitArrayBound(name, GV);
 155     emitGlobalDirective(name);
 156     // TODO Use COMDAT groups for LinkOnceLinkage
 157     if (GV->hasWeakLinkage() || GV->hasLinkOnceLinkage()) {
 158       O << TAI->getWeakDefDirective() << name << "\n";
 159     }
 160     // FALL THROUGH
 161   case GlobalValue::InternalLinkage:
 162   case GlobalValue::PrivateLinkage:
 163   case GlobalValue::LinkerPrivateLinkage:
 164     break;
 165   case GlobalValue::GhostLinkage:
 166     llvm_unreachable("Should not have any unmaterialized functions!");
 167   case GlobalValue::DLLImportLinkage:
 168     llvm_unreachable("DLLImport linkage is not supported by this target!");
 169   case GlobalValue::DLLExportLinkage:
 170     llvm_unreachable("DLLExport linkage is not supported by this target!");
 171   default:
 172     llvm_unreachable("Unknown linkage type!");
 173   }
 174
 175   EmitAlignment(Align, GV, 2);
 176
 177   unsigned Size = TD->getTypeAllocSize(C->getType());
 178   if (GV->isThreadLocal()) {
 179     Size *= MaxThreads;
 180   }
 181   if (TAI->hasDotTypeDotSizeDirective()) {
 182     O << "\t.type " << name << ",@object\n";
 183     O << "\t.size " << name << "," << Size << "\n";
 184   }
 185   O << name << ":\n";
 186
 187   EmitGlobalConstant(C);
 188   if (GV->isThreadLocal()) {
 189     for (unsigned i = 1; i < MaxThreads; ++i) {
 190       EmitGlobalConstant(C);
 191     }
 192   }
 193   if (Size < 4) {
 194     // The ABI requires that unsigned scalar types smaller than 32 bits
 195     // are are padded to 32 bits.
 196     EmitZeros(4 - Size);
 197   }
 198
 199   // Mark the end of the global
 200   O << "\t.cc_bottom " << name << ".data\n";
 201 }
 202
 203 /// Emit the directives on the start of functions
 204 void XCoreAsmPrinter::emitFunctionStart(MachineFunction &MF) {
 205   // Print out the label for the function.
 206   const Function *F = MF.getFunction();
 207
 208   SwitchToSection(getObjFileLowering().SectionForGlobal(F, Mang, TM));
 209
 210   // Mark the start of the function
 211   O << "\t.cc_top " << CurrentFnName << ".function," << CurrentFnName << "\n";
 212
 213   switch (F->getLinkage()) {
 214   default: llvm_unreachable("Unknown linkage type!");
 215   case Function::InternalLinkage:  // Symbols default to internal.
 216   case Function::PrivateLinkage:
 217   case Function::LinkerPrivateLinkage:
 218     break;
 219   case Function::ExternalLinkage:
 220     emitGlobalDirective(CurrentFnName);
 221     break;
 222   case Function::LinkOnceAnyLinkage:
 223   case Function::LinkOnceODRLinkage:
 224   case Function::WeakAnyLinkage:
 225   case Function::WeakODRLinkage:
 226     // TODO Use COMDAT groups for LinkOnceLinkage
 227     O << TAI->getGlobalDirective() << CurrentFnName << "\n";
 228     O << TAI->getWeakDefDirective() << CurrentFnName << "\n";
 229     break;
 230   }
 231   // (1 << 1) byte aligned
 232   EmitAlignment(MF.getAlignment(), F, 1);
 233   if (TAI->hasDotTypeDotSizeDirective()) {
 234     O << "\t.type " << CurrentFnName << ",@function\n";
 235   }
 236   O << CurrentFnName << ":\n";
 237 }
 238
 239 /// Emit the directives on the end of functions
 240 void XCoreAsmPrinter::
 241 emitFunctionEnd(MachineFunction &MF)
 242 {
 243   // Mark the end of the function
 244   O << "\t.cc_bottom " << CurrentFnName << ".function\n";
 245 }
 246
 247 /// runOnMachineFunction - This uses the printMachineInstruction()
 248 /// method to print assembly for each instruction.
 249 ///
 250 bool XCoreAsmPrinter::runOnMachineFunction(MachineFunction &MF)
 251 {
 252   this->MF = &MF;
 253
 254   SetupMachineFunction(MF);
 255
 256   // Print out constants referenced by the function
 257   EmitConstantPool(MF.getConstantPool());
 258
 259   // Print out jump tables referenced by the function
 260   EmitJumpTableInfo(MF.getJumpTableInfo(), MF);
 261
 262   // Emit the function start directives
 263   emitFunctionStart(MF);
 264
 265   // Emit pre-function debug information.
 266   DW->BeginFunction(&MF);
 267
 268   // Print out code for the function.
 269   for (MachineFunction::const_iterator I = MF.begin(), E = MF.end();
 270        I != E; ++I) {
 271
 272     // Print a label for the basic block.
 273     if (I != MF.begin()) {
 274       printBasicBlockLabel(I, true , true);
 275       O << '\n';
 276     }
 277
 278     for (MachineBasicBlock::const_iterator II = I->begin(), E = I->end();
 279          II != E; ++II) {
 280       // Print the assembly for the instruction.
 281       O << "\t";
 282       printMachineInstruction(II);
 283     }
 284
 285     // Each Basic Block is separated by a newline
 286     O << '\n';
 287   }
 288
 289   // Emit function end directives
 290   emitFunctionEnd(MF);
 291
 292   // Emit post-function debug information.
 293   DW->EndFunction(&MF);
 294
 295   // We didn't modify anything.
 296   return false;
 297 }
 298
 299 void XCoreAsmPrinter::printMemOperand(const MachineInstr *MI, int opNum)
 300 {
 301   printOperand(MI, opNum);
 302
 303   if (MI->getOperand(opNum+1).isImm()
 304     && MI->getOperand(opNum+1).getImm() == 0)
 305     return;
 306
 307   O << "+";
 308   printOperand(MI, opNum+1);
 309 }
 310
 311 void XCoreAsmPrinter::printOperand(const MachineInstr *MI, int opNum) {
 312   const MachineOperand &MO = MI->getOperand(opNum);
 313   switch (MO.getType()) {
 314   case MachineOperand::MO_Register:
 315     if (TargetRegisterInfo::isPhysicalRegister(MO.getReg()))
 316       O << TM.getRegisterInfo()->get(MO.getReg()).AsmName;
 317     else
 318       llvm_unreachable("not implemented");
 319     break;
 320   case MachineOperand::MO_Immediate:
 321     O << MO.getImm();
 322     break;
 323   case MachineOperand::MO_MachineBasicBlock:
 324     printBasicBlockLabel(MO.getMBB());
 325     break;
 326   case MachineOperand::MO_GlobalAddress:
 327     O << Mang->getMangledName(MO.getGlobal());
 328     break;
 329   case MachineOperand::MO_ExternalSymbol:
 330     O << MO.getSymbolName();
 331     break;
 332   case MachineOperand::MO_ConstantPoolIndex:
 333     O << TAI->getPrivateGlobalPrefix() << "CPI" << getFunctionNumber()
 334       << '_' << MO.getIndex();
 335     break;
 336   case MachineOperand::MO_JumpTableIndex:
 337     O << TAI->getPrivateGlobalPrefix() << "JTI" << getFunctionNumber()
 338       << '_' << MO.getIndex();
 339     break;
 340   default:
 341     llvm_unreachable("not implemented");
 342   }
 343 }
 344
 345 /// PrintAsmOperand - Print out an operand for an inline asm expression.
 346 ///
 347 bool XCoreAsmPrinter::PrintAsmOperand(const MachineInstr *MI, unsigned OpNo,
 348                                       unsigned AsmVariant,
 349                                       const char *ExtraCode) {
 350   printOperand(MI, OpNo);
 351   return false;
 352 }
 353
 354 void XCoreAsmPrinter::printMachineInstruction(const MachineInstr *MI) {
 355   ++EmittedInsts;
 356
 357   // Check for mov mnemonic
 358   unsigned src, dst, srcSR, dstSR;
 359   if (TM.getInstrInfo()->isMoveInstr(*MI, src, dst, srcSR, dstSR)) {
 360     O << "\tmov ";
 361     O << TM.getRegisterInfo()->get(dst).AsmName;
 362     O << ", ";
 363     O << TM.getRegisterInfo()->get(src).AsmName;
 364     O << "\n";
 365     return;
 366   }
 367   if (printInstruction(MI)) {
 368     return;
 369   }
 370   llvm_unreachable("Unhandled instruction in asm writer!");
 371 }
 372
 373 bool XCoreAsmPrinter::doInitialization(Module &M) {
 374   bool Result = AsmPrinter::doInitialization(M);
 375   DW = getAnalysisIfAvailable<DwarfWriter>();
 376
 377   return Result;
 378 }
 379
 380
 381
 382 // Force static initialization.
 383 extern "C" void LLVMInitializeXCoreTarget() {
 384   RegisterTargetMachine<XCoreTargetMachine> X(TheXCoreTarget);
 385   RegisterAsmPrinter<XCoreAsmPrinter> Y(TheXCoreTarget);
 386 }