lib/Target/XCore/XCoreAsmPrinter.cpp

   1 //===-- XCoreAsmPrinter.cpp - XCore LLVM assembly writer ------------------===//
   2 //
   3 // Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
   4 // See https://llvm.org/LICENSE.txt for license information.
   5 // SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
   6 //
   7 //===----------------------------------------------------------------------===//
   8 //
   9 // This file contains a printer that converts from our internal representation
  10 // of machine-dependent LLVM code to the XAS-format XCore assembly language.
  11 //
  12 //===----------------------------------------------------------------------===//
  13
  14 #include "InstPrinter/XCoreInstPrinter.h"
  15 #include "XCore.h"
  16 #include "XCoreInstrInfo.h"
  17 #include "XCoreMCInstLower.h"
  18 #include "XCoreSubtarget.h"
  19 #include "XCoreTargetMachine.h"
  20 #include "XCoreTargetStreamer.h"
  21 #include "llvm/ADT/SmallString.h"
  22 #include "llvm/ADT/StringExtras.h"
  23 #include "llvm/CodeGen/AsmPrinter.h"
  24 #include "llvm/CodeGen/MachineConstantPool.h"
  25 #include "llvm/CodeGen/MachineFunctionPass.h"
  26 #include "llvm/CodeGen/MachineInstr.h"
  27 #include "llvm/CodeGen/MachineJumpTableInfo.h"
  28 #include "llvm/CodeGen/MachineModuleInfo.h"
  29 #include "llvm/IR/Constants.h"
  30 #include "llvm/IR/DataLayout.h"
  31 #include "llvm/IR/DebugInfo.h"
  32 #include "llvm/IR/DerivedTypes.h"
  33 #include "llvm/IR/Mangler.h"
  34 #include "llvm/IR/Module.h"
  35 #include "llvm/MC/MCAsmInfo.h"
  36 #include "llvm/MC/MCExpr.h"
  37 #include "llvm/MC/MCInst.h"
  38 #include "llvm/MC/MCStreamer.h"
  39 #include "llvm/MC/MCSymbolELF.h"
  40 #include "llvm/Support/ErrorHandling.h"
  41 #include "llvm/Support/TargetRegistry.h"
  42 #include "llvm/Support/raw_ostream.h"
  43 #include "llvm/Target/TargetLoweringObjectFile.h"
  44 #include <algorithm>
  45 #include <cctype>
  46 using namespace llvm;
  47
  48 #define DEBUG_TYPE "asm-printer"
  49
  50 namespace {
  51   class XCoreAsmPrinter : public AsmPrinter {
  52     XCoreMCInstLower MCInstLowering;
  53     XCoreTargetStreamer &getTargetStreamer();
  54
  55   public:
  56     explicit XCoreAsmPrinter(TargetMachine &TM,
  57                              std::unique_ptr<MCStreamer> Streamer)
  58         : AsmPrinter(TM, std::move(Streamer)), MCInstLowering(*this) {}
  59
  60     StringRef getPassName() const override { return "XCore Assembly Printer"; }
  61
  62     void printInlineJT(const MachineInstr *MI, int opNum, raw_ostream &O,
  63                        const std::string &directive = ".jmptable");
  64     void printInlineJT32(const MachineInstr *MI, int opNum, raw_ostream &O) {
  65       printInlineJT(MI, opNum, O, ".jmptable32");
  66     }
  67     void printOperand(const MachineInstr *MI, int opNum, raw_ostream &O);
  68     bool PrintAsmOperand(const MachineInstr *MI, unsigned OpNo,
  69                          unsigned AsmVariant, const char *ExtraCode,
  70                          raw_ostream &O) override;
  71     bool PrintAsmMemoryOperand(const MachineInstr *MI, unsigned OpNum,
  72                                unsigned AsmVariant, const char *ExtraCode,
  73                                raw_ostream &O) override;
  74
  75     void emitArrayBound(MCSymbol *Sym, const GlobalVariable *GV);
  76     void EmitGlobalVariable(const GlobalVariable *GV) override;
  77
  78     void EmitFunctionEntryLabel() override;
  79     void EmitInstruction(const MachineInstr *MI) override;
  80     void EmitFunctionBodyStart() override;
  81     void EmitFunctionBodyEnd() override;
  82   };
  83 } // end of anonymous namespace
  84
  85 XCoreTargetStreamer &XCoreAsmPrinter::getTargetStreamer() {
  86   return static_cast<XCoreTargetStreamer&>(*OutStreamer->getTargetStreamer());
  87 }
  88
  89 void XCoreAsmPrinter::emitArrayBound(MCSymbol *Sym, const GlobalVariable *GV) {
  90   assert( ( GV->hasExternalLinkage() || GV->hasWeakLinkage() ||
  91             GV->hasLinkOnceLinkage() || GV->hasCommonLinkage() ) &&
  92           "Unexpected linkage");
  93   if (ArrayType *ATy = dyn_cast<ArrayType>(GV->getValueType())) {
  94
  95     MCSymbol *SymGlob = OutContext.getOrCreateSymbol(
  96                           Twine(Sym->getName() + StringRef(".globound")));
  97     OutStreamer->EmitSymbolAttribute(SymGlob, MCSA_Global);
  98     OutStreamer->EmitAssignment(SymGlob,
  99                                 MCConstantExpr::create(ATy->getNumElements(),
 100                                                        OutContext));
 101     if (GV->hasWeakLinkage() || GV->hasLinkOnceLinkage() ||
 102         GV->hasCommonLinkage()) {
 103       OutStreamer->EmitSymbolAttribute(SymGlob, MCSA_Weak);
 104     }
 105   }
 106 }
 107
 108 void XCoreAsmPrinter::EmitGlobalVariable(const GlobalVariable *GV) {
 109   // Check to see if this is a special global used by LLVM, if so, emit it.
 110   if (!GV->hasInitializer() ||
 111       EmitSpecialLLVMGlobal(GV))
 112     return;
 113
 114   const DataLayout &DL = getDataLayout();
 115   OutStreamer->SwitchSection(getObjFileLowering().SectionForGlobal(GV, TM));
 116
 117   MCSymbol *GVSym = getSymbol(GV);
 118   const Constant *C = GV->getInitializer();
 119   unsigned Align = (unsigned)DL.getPreferredTypeAlignmentShift(C->getType());
 120
 121   // Mark the start of the global
 122   getTargetStreamer().emitCCTopData(GVSym->getName());
 123
 124   switch (GV->getLinkage()) {
 125   case GlobalValue::AppendingLinkage:
 126     report_fatal_error("AppendingLinkage is not supported by this target!");
 127   case GlobalValue::LinkOnceAnyLinkage:
 128   case GlobalValue::LinkOnceODRLinkage:
 129   case GlobalValue::WeakAnyLinkage:
 130   case GlobalValue::WeakODRLinkage:
 131   case GlobalValue::ExternalLinkage:
 132   case GlobalValue::CommonLinkage:
 133     emitArrayBound(GVSym, GV);
 134     OutStreamer->EmitSymbolAttribute(GVSym, MCSA_Global);
 135
 136     if (GV->hasWeakLinkage() || GV->hasLinkOnceLinkage() ||
 137         GV->hasCommonLinkage())
 138       OutStreamer->EmitSymbolAttribute(GVSym, MCSA_Weak);
 139     LLVM_FALLTHROUGH;
 140   case GlobalValue::InternalLinkage:
 141   case GlobalValue::PrivateLinkage:
 142     break;
 143   default:
 144     llvm_unreachable("Unknown linkage type!");
 145   }
 146
 147   EmitAlignment(Align > 2 ? Align : 2, GV);
 148
 149   if (GV->isThreadLocal()) {
 150     report_fatal_error("TLS is not supported by this target!");
 151   }
 152   unsigned Size = DL.getTypeAllocSize(C->getType());
 153   if (MAI->hasDotTypeDotSizeDirective()) {
 154     OutStreamer->EmitSymbolAttribute(GVSym, MCSA_ELF_TypeObject);
 155     OutStreamer->emitELFSize(GVSym, MCConstantExpr::create(Size, OutContext));
 156   }
 157   OutStreamer->EmitLabel(GVSym);
 158
 159   EmitGlobalConstant(DL, C);
 160   // The ABI requires that unsigned scalar types smaller than 32 bits
 161   // are padded to 32 bits.
 162   if (Size < 4)
 163     OutStreamer->EmitZeros(4 - Size);
 164
 165   // Mark the end of the global
 166   getTargetStreamer().emitCCBottomData(GVSym->getName());
 167 }
 168
 169 void XCoreAsmPrinter::EmitFunctionBodyStart() {
 170   MCInstLowering.Initialize(&MF->getContext());
 171 }
 172
 173 /// EmitFunctionBodyEnd - Targets can override this to emit stuff after
 174 /// the last basic block in the function.
 175 void XCoreAsmPrinter::EmitFunctionBodyEnd() {
 176   // Emit function end directives
 177   getTargetStreamer().emitCCBottomFunction(CurrentFnSym->getName());
 178 }
 179
 180 void XCoreAsmPrinter::EmitFunctionEntryLabel() {
 181   // Mark the start of the function
 182   getTargetStreamer().emitCCTopFunction(CurrentFnSym->getName());
 183   OutStreamer->EmitLabel(CurrentFnSym);
 184 }
 185
 186 void XCoreAsmPrinter::
 187 printInlineJT(const MachineInstr *MI, int opNum, raw_ostream &O,
 188               const std::string &directive) {
 189   unsigned JTI = MI->getOperand(opNum).getIndex();
 190   const MachineFunction *MF = MI->getParent()->getParent();
 191   const MachineJumpTableInfo *MJTI = MF->getJumpTableInfo();
 192   const std::vector<MachineJumpTableEntry> &JT = MJTI->getJumpTables();
 193   const std::vector<MachineBasicBlock*> &JTBBs = JT[JTI].MBBs;
 194   O << "\t" << directive << " ";
 195   for (unsigned i = 0, e = JTBBs.size(); i != e; ++i) {
 196     MachineBasicBlock *MBB = JTBBs[i];
 197     if (i > 0)
 198       O << ",";
 199     MBB->getSymbol()->print(O, MAI);
 200   }
 201 }
 202
 203 void XCoreAsmPrinter::printOperand(const MachineInstr *MI, int opNum,
 204                                    raw_ostream &O) {
 205   const DataLayout &DL = getDataLayout();
 206   const MachineOperand &MO = MI->getOperand(opNum);
 207   switch (MO.getType()) {
 208   case MachineOperand::MO_Register:
 209     O << XCoreInstPrinter::getRegisterName(MO.getReg());
 210     break;
 211   case MachineOperand::MO_Immediate:
 212     O << MO.getImm();
 213     break;
 214   case MachineOperand::MO_MachineBasicBlock:
 215     MO.getMBB()->getSymbol()->print(O, MAI);
 216     break;
 217   case MachineOperand::MO_GlobalAddress:
 218     getSymbol(MO.getGlobal())->print(O, MAI);
 219     break;
 220   case MachineOperand::MO_ConstantPoolIndex:
 221     O << DL.getPrivateGlobalPrefix() << "CPI" << getFunctionNumber() << '_'
 222       << MO.getIndex();
 223     break;
 224   case MachineOperand::MO_BlockAddress:
 225     GetBlockAddressSymbol(MO.getBlockAddress())->print(O, MAI);
 226     break;
 227   default:
 228     llvm_unreachable("not implemented");
 229   }
 230 }
 231
 232 /// PrintAsmOperand - Print out an operand for an inline asm expression.
 233 ///
 234 bool XCoreAsmPrinter::PrintAsmOperand(const MachineInstr *MI, unsigned OpNo,
 235                                       unsigned AsmVariant,const char *ExtraCode,
 236                                       raw_ostream &O) {
 237   // Print the operand if there is no operand modifier.
 238   if (!ExtraCode || !ExtraCode[0]) {
 239     printOperand(MI, OpNo, O);
 240     return false;
 241   }
 242
 243   // Otherwise fallback on the default implementation.
 244   return AsmPrinter::PrintAsmOperand(MI, OpNo, AsmVariant, ExtraCode, O);
 245 }
 246
 247 bool XCoreAsmPrinter::
 248 PrintAsmMemoryOperand(const MachineInstr *MI, unsigned OpNum,
 249                       unsigned AsmVariant, const char *ExtraCode,
 250                       raw_ostream &O) {
 251   if (ExtraCode && ExtraCode[0]) {
 252     return true; // Unknown modifier.
 253   }
 254   printOperand(MI, OpNum, O);
 255   O << '[';
 256   printOperand(MI, OpNum + 1, O);
 257   O << ']';
 258   return false;
 259 }
 260
 261 void XCoreAsmPrinter::EmitInstruction(const MachineInstr *MI) {
 262   SmallString<128> Str;
 263   raw_svector_ostream O(Str);
 264
 265   switch (MI->getOpcode()) {
 266   case XCore::DBG_VALUE:
 267     llvm_unreachable("Should be handled target independently");
 268   case XCore::ADD_2rus:
 269     if (MI->getOperand(2).getImm() == 0) {
 270       O << "\tmov "
 271         << XCoreInstPrinter::getRegisterName(MI->getOperand(0).getReg()) << ", "
 272         << XCoreInstPrinter::getRegisterName(MI->getOperand(1).getReg());
 273       OutStreamer->EmitRawText(O.str());
 274       return;
 275     }
 276     break;
 277   case XCore::BR_JT:
 278   case XCore::BR_JT32:
 279     O << "\tbru "
 280       << XCoreInstPrinter::getRegisterName(MI->getOperand(1).getReg()) << '\n';
 281     if (MI->getOpcode() == XCore::BR_JT)
 282       printInlineJT(MI, 0, O);
 283     else
 284       printInlineJT32(MI, 0, O);
 285     O << '\n';
 286     OutStreamer->EmitRawText(O.str());
 287     return;
 288   }
 289
 290   MCInst TmpInst;
 291   MCInstLowering.Lower(MI, TmpInst);
 292
 293   EmitToStreamer(*OutStreamer, TmpInst);
 294 }
 295
 296 // Force static initialization.
 297 extern "C" void LLVMInitializeXCoreAsmPrinter() {
 298   RegisterAsmPrinter<XCoreAsmPrinter> X(getTheXCoreTarget());
 299 }