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