src/llvm/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 #include "XCore.h"
  16 #include "InstPrinter/XCoreInstPrinter.h"
  17 #include "XCoreInstrInfo.h"
  18 #include "XCoreMCInstLower.h"
  19 #include "XCoreSubtarget.h"
  20 #include "XCoreTargetMachine.h"
  21 #include "XCoreTargetStreamer.h"
  22 #include "llvm/ADT/SmallString.h"
  23 #include "llvm/ADT/StringExtras.h"
  24 #include "llvm/CodeGen/AsmPrinter.h"
  25 #include "llvm/CodeGen/MachineConstantPool.h"
  26 #include "llvm/CodeGen/MachineFunctionPass.h"
  27 #include "llvm/CodeGen/MachineInstr.h"
  28 #include "llvm/CodeGen/MachineJumpTableInfo.h"
  29 #include "llvm/CodeGen/MachineModuleInfo.h"
  30 #include "llvm/IR/Constants.h"
  31 #include "llvm/IR/DataLayout.h"
  32 #include "llvm/IR/DebugInfo.h"
  33 #include "llvm/IR/DerivedTypes.h"
  34 #include "llvm/IR/Mangler.h"
  35 #include "llvm/IR/Module.h"
  36 #include "llvm/MC/MCAsmInfo.h"
  37 #include "llvm/MC/MCExpr.h"
  38 #include "llvm/MC/MCInst.h"
  39 #include "llvm/MC/MCStreamer.h"
  40 #include "llvm/MC/MCSymbol.h"
  41 #include "llvm/Support/ErrorHandling.h"
  42 #include "llvm/Support/TargetRegistry.h"
  43 #include "llvm/Support/raw_ostream.h"
  44 #include "llvm/Target/TargetLoweringObjectFile.h"
  45 #include <algorithm>
  46 #include <cctype>
  47 using namespace llvm;
  48
  49 #define DEBUG_TYPE "asm-printer"
  50
  51 namespace {
  52   class XCoreAsmPrinter : public AsmPrinter {
  53     const XCoreSubtarget &Subtarget;
  54     XCoreMCInstLower MCInstLowering;
  55     XCoreTargetStreamer &getTargetStreamer();
  56
  57   public:
  58     explicit XCoreAsmPrinter(TargetMachine &TM, MCStreamer &Streamer)
  59       : AsmPrinter(TM, Streamer), Subtarget(TM.getSubtarget<XCoreSubtarget>()),
  60         MCInstLowering(*this) {}
  61
  62     const char *getPassName() const override {
  63       return "XCore Assembly Printer";
  64     }
  65
  66     void printInlineJT(const MachineInstr *MI, int opNum, raw_ostream &O,
  67                        const std::string &directive = ".jmptable");
  68     void printInlineJT32(const MachineInstr *MI, int opNum, raw_ostream &O) {
  69       printInlineJT(MI, opNum, O, ".jmptable32");
  70     }
  71     void printOperand(const MachineInstr *MI, int opNum, raw_ostream &O);
  72     bool PrintAsmOperand(const MachineInstr *MI, unsigned OpNo,
  73                          unsigned AsmVariant, const char *ExtraCode,
  74                          raw_ostream &O) override;
  75     bool PrintAsmMemoryOperand(const MachineInstr *MI, unsigned OpNum,
  76                                unsigned AsmVariant, const char *ExtraCode,
  77                                raw_ostream &O) override;
  78
  79     void emitArrayBound(MCSymbol *Sym, const GlobalVariable *GV);
  80     void EmitGlobalVariable(const GlobalVariable *GV) override;
  81
  82     void EmitFunctionEntryLabel() override;
  83     void EmitInstruction(const MachineInstr *MI) override;
  84     void EmitFunctionBodyStart() override;
  85     void EmitFunctionBodyEnd() override;
  86   };
  87 } // end of anonymous namespace
  88
  89 XCoreTargetStreamer &XCoreAsmPrinter::getTargetStreamer() {
  90   return static_cast<XCoreTargetStreamer&>(*OutStreamer.getTargetStreamer());
  91 }
  92
  93 void XCoreAsmPrinter::emitArrayBound(MCSymbol *Sym, const GlobalVariable *GV) {
  94   assert( ( GV->hasExternalLinkage() || GV->hasWeakLinkage() ||
  95             GV->hasLinkOnceLinkage() || GV->hasCommonLinkage() ) &&
  96           "Unexpected linkage");
  97   if (ArrayType *ATy = dyn_cast<ArrayType>(
  98                         cast<PointerType>(GV->getType())->getElementType())) {
  99
 100     MCSymbol *SymGlob = OutContext.GetOrCreateSymbol(
 101                           Twine(Sym->getName() + StringRef(".globound")));
 102     OutStreamer.EmitSymbolAttribute(SymGlob, MCSA_Global);
 103     OutStreamer.EmitAssignment(SymGlob,
 104                                MCConstantExpr::Create(ATy->getNumElements(),
 105                                                       OutContext));
 106     if (GV->hasWeakLinkage() || GV->hasLinkOnceLinkage() ||
 107         GV->hasCommonLinkage()) {
 108       // TODO Use COMDAT groups for LinkOnceLinkage
 109       OutStreamer.EmitSymbolAttribute(SymGlob, MCSA_Weak);
 110     }
 111   }
 112 }
 113
 114 void XCoreAsmPrinter::EmitGlobalVariable(const GlobalVariable *GV) {
 115   // Check to see if this is a special global used by LLVM, if so, emit it.
 116   if (!GV->hasInitializer() ||
 117       EmitSpecialLLVMGlobal(GV))
 118     return;
 119
 120   const DataLayout *TD = TM.getSubtargetImpl()->getDataLayout();
 121   OutStreamer.SwitchSection(
 122       getObjFileLowering().SectionForGlobal(GV, *Mang, TM));
 123
 124   MCSymbol *GVSym = getSymbol(GV);
 125   const Constant *C = GV->getInitializer();
 126   unsigned Align = (unsigned)TD->getPreferredTypeAlignmentShift(C->getType());
 127
 128   // Mark the start of the global
 129   getTargetStreamer().emitCCTopData(GVSym->getName());
 130
 131   switch (GV->getLinkage()) {
 132   case GlobalValue::AppendingLinkage:
 133     report_fatal_error("AppendingLinkage is not supported by this target!");
 134   case GlobalValue::LinkOnceAnyLinkage:
 135   case GlobalValue::LinkOnceODRLinkage:
 136   case GlobalValue::WeakAnyLinkage:
 137   case GlobalValue::WeakODRLinkage:
 138   case GlobalValue::ExternalLinkage:
 139   case GlobalValue::CommonLinkage:
 140     emitArrayBound(GVSym, GV);
 141     OutStreamer.EmitSymbolAttribute(GVSym, MCSA_Global);
 142
 143     // TODO Use COMDAT groups for LinkOnceLinkage
 144     if (GV->hasWeakLinkage() || GV->hasLinkOnceLinkage() ||
 145         GV->hasCommonLinkage())
 146       OutStreamer.EmitSymbolAttribute(GVSym, MCSA_Weak);
 147     // FALL THROUGH
 148   case GlobalValue::InternalLinkage:
 149   case GlobalValue::PrivateLinkage:
 150     break;
 151   default:
 152     llvm_unreachable("Unknown linkage type!");
 153   }
 154
 155   EmitAlignment(Align > 2 ? Align : 2, GV);
 156
 157   if (GV->isThreadLocal()) {
 158     report_fatal_error("TLS is not supported by this target!");
 159   }
 160   unsigned Size = TD->getTypeAllocSize(C->getType());
 161   if (MAI->hasDotTypeDotSizeDirective()) {
 162     OutStreamer.EmitSymbolAttribute(GVSym, MCSA_ELF_TypeObject);
 163     OutStreamer.EmitELFSize(GVSym, MCConstantExpr::Create(Size, OutContext));
 164   }
 165   OutStreamer.EmitLabel(GVSym);
 166
 167   EmitGlobalConstant(C);
 168   // The ABI requires that unsigned scalar types smaller than 32 bits
 169   // are padded to 32 bits.
 170   if (Size < 4)
 171     OutStreamer.EmitZeros(4 - Size);
 172
 173   // Mark the end of the global
 174   getTargetStreamer().emitCCBottomData(GVSym->getName());
 175 }
 176
 177 void XCoreAsmPrinter::EmitFunctionBodyStart() {
 178   MCInstLowering.Initialize(Mang, &MF->getContext());
 179 }
 180
 181 /// EmitFunctionBodyEnd - Targets can override this to emit stuff after
 182 /// the last basic block in the function.
 183 void XCoreAsmPrinter::EmitFunctionBodyEnd() {
 184   // Emit function end directives
 185   getTargetStreamer().emitCCBottomFunction(CurrentFnSym->getName());
 186 }
 187
 188 void XCoreAsmPrinter::EmitFunctionEntryLabel() {
 189   // Mark the start of the function
 190   getTargetStreamer().emitCCTopFunction(CurrentFnSym->getName());
 191   OutStreamer.EmitLabel(CurrentFnSym);
 192 }
 193
 194 void XCoreAsmPrinter::
 195 printInlineJT(const MachineInstr *MI, int opNum, raw_ostream &O,
 196               const std::string &directive) {
 197   unsigned JTI = MI->getOperand(opNum).getIndex();
 198   const MachineFunction *MF = MI->getParent()->getParent();
 199   const MachineJumpTableInfo *MJTI = MF->getJumpTableInfo();
 200   const std::vector<MachineJumpTableEntry> &JT = MJTI->getJumpTables();
 201   const std::vector<MachineBasicBlock*> &JTBBs = JT[JTI].MBBs;
 202   O << "\t" << directive << " ";
 203   for (unsigned i = 0, e = JTBBs.size(); i != e; ++i) {
 204     MachineBasicBlock *MBB = JTBBs[i];
 205     if (i > 0)
 206       O << ",";
 207     O << *MBB->getSymbol();
 208   }
 209 }
 210
 211 void XCoreAsmPrinter::printOperand(const MachineInstr *MI, int opNum,
 212                                    raw_ostream &O) {
 213   const DataLayout *DL = TM.getSubtargetImpl()->getDataLayout();
 214   const MachineOperand &MO = MI->getOperand(opNum);
 215   switch (MO.getType()) {
 216   case MachineOperand::MO_Register:
 217     O << XCoreInstPrinter::getRegisterName(MO.getReg());
 218     break;
 219   case MachineOperand::MO_Immediate:
 220     O << MO.getImm();
 221     break;
 222   case MachineOperand::MO_MachineBasicBlock:
 223     O << *MO.getMBB()->getSymbol();
 224     break;
 225   case MachineOperand::MO_GlobalAddress:
 226     O << *getSymbol(MO.getGlobal());
 227     break;
 228   case MachineOperand::MO_ConstantPoolIndex:
 229     O << DL->getPrivateGlobalPrefix() << "CPI" << getFunctionNumber()
 230       << '_' << MO.getIndex();
 231     break;
 232   case MachineOperand::MO_BlockAddress:
 233     O << *GetBlockAddressSymbol(MO.getBlockAddress());
 234     break;
 235   default:
 236     llvm_unreachable("not implemented");
 237   }
 238 }
 239
 240 /// PrintAsmOperand - Print out an operand for an inline asm expression.
 241 ///
 242 bool XCoreAsmPrinter::PrintAsmOperand(const MachineInstr *MI, unsigned OpNo,
 243                                       unsigned AsmVariant,const char *ExtraCode,
 244                                       raw_ostream &O) {
 245   // Print the operand if there is no operand modifier.
 246   if (!ExtraCode || !ExtraCode[0]) {
 247     printOperand(MI, OpNo, O);
 248     return false;
 249   }
 250
 251   // Otherwise fallback on the default implementation.
 252   return AsmPrinter::PrintAsmOperand(MI, OpNo, AsmVariant, ExtraCode, O);
 253 }
 254
 255 bool XCoreAsmPrinter::
 256 PrintAsmMemoryOperand(const MachineInstr *MI, unsigned OpNum,
 257                       unsigned AsmVariant, const char *ExtraCode,
 258                       raw_ostream &O) {
 259   if (ExtraCode && ExtraCode[0]) {
 260     return true; // Unknown modifier.
 261   }
 262   printOperand(MI, OpNum, O);
 263   O << '[';
 264   printOperand(MI, OpNum + 1, O);
 265   O << ']';
 266   return false;
 267 }
 268
 269 void XCoreAsmPrinter::EmitInstruction(const MachineInstr *MI) {
 270   SmallString<128> Str;
 271   raw_svector_ostream O(Str);
 272
 273   switch (MI->getOpcode()) {
 274   case XCore::DBG_VALUE:
 275     llvm_unreachable("Should be handled target independently");
 276   case XCore::ADD_2rus:
 277     if (MI->getOperand(2).getImm() == 0) {
 278       O << "\tmov "
 279         << XCoreInstPrinter::getRegisterName(MI->getOperand(0).getReg()) << ", "
 280         << XCoreInstPrinter::getRegisterName(MI->getOperand(1).getReg());
 281       OutStreamer.EmitRawText(O.str());
 282       return;
 283     }
 284     break;
 285   case XCore::BR_JT:
 286   case XCore::BR_JT32:
 287     O << "\tbru "
 288       << XCoreInstPrinter::getRegisterName(MI->getOperand(1).getReg()) << '\n';
 289     if (MI->getOpcode() == XCore::BR_JT)
 290       printInlineJT(MI, 0, O);
 291     else
 292       printInlineJT32(MI, 0, O);
 293     O << '\n';
 294     OutStreamer.EmitRawText(O.str());
 295     return;
 296   }
 297
 298   MCInst TmpInst;
 299   MCInstLowering.Lower(MI, TmpInst);
 300
 301   EmitToStreamer(OutStreamer, TmpInst);
 302 }
 303
 304 // Force static initialization.
 305 extern "C" void LLVMInitializeXCoreAsmPrinter() {
 306   RegisterAsmPrinter<XCoreAsmPrinter> X(TheXCoreTarget);
 307 }