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