llvm/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/MC/TargetRegistry.h"
  42 #include "llvm/Support/ErrorHandling.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() || emitSpecialLLVMGlobal(GV))
 110     return;
 111
 112   const DataLayout &DL = getDataLayout();
 113   OutStreamer->switchSection(getObjFileLowering().SectionForGlobal(GV, TM));
 114
 115   MCSymbol *GVSym = getSymbol(GV);
 116   const Constant *C = GV->getInitializer();
 117   const Align Alignment = DL.getPrefTypeAlign(C->getType());
 118
 119   // Mark the start of the global
 120   getTargetStreamer().emitCCTopData(GVSym->getName());
 121
 122   switch (GV->getLinkage()) {
 123   case GlobalValue::AppendingLinkage:
 124     report_fatal_error("AppendingLinkage is not supported by this target!");
 125   case GlobalValue::LinkOnceAnyLinkage:
 126   case GlobalValue::LinkOnceODRLinkage:
 127   case GlobalValue::WeakAnyLinkage:
 128   case GlobalValue::WeakODRLinkage:
 129   case GlobalValue::ExternalLinkage:
 130   case GlobalValue::CommonLinkage:
 131     emitArrayBound(GVSym, GV);
 132     OutStreamer->emitSymbolAttribute(GVSym, MCSA_Global);
 133
 134     if (GV->hasWeakLinkage() || GV->hasLinkOnceLinkage() ||
 135         GV->hasCommonLinkage())
 136       OutStreamer->emitSymbolAttribute(GVSym, MCSA_Weak);
 137     [[fallthrough]];
 138   case GlobalValue::InternalLinkage:
 139   case GlobalValue::PrivateLinkage:
 140     break;
 141   default:
 142     llvm_unreachable("Unknown linkage type!");
 143   }
 144
 145   emitAlignment(std::max(Alignment, Align(4)), GV);
 146
 147   if (GV->isThreadLocal()) {
 148     report_fatal_error("TLS is not supported by this target!");
 149   }
 150   unsigned Size = DL.getTypeAllocSize(C->getType());
 151   if (MAI->hasDotTypeDotSizeDirective()) {
 152     OutStreamer->emitSymbolAttribute(GVSym, MCSA_ELF_TypeObject);
 153     OutStreamer->emitELFSize(GVSym, MCConstantExpr::create(Size, OutContext));
 154   }
 155   OutStreamer->emitLabel(GVSym);
 156
 157   emitGlobalConstant(DL, C);
 158   // The ABI requires that unsigned scalar types smaller than 32 bits
 159   // are padded to 32 bits.
 160   if (Size < 4)
 161     OutStreamer->emitZeros(4 - Size);
 162
 163   // Mark the end of the global
 164   getTargetStreamer().emitCCBottomData(GVSym->getName());
 165 }
 166
 167 void XCoreAsmPrinter::emitFunctionBodyStart() {
 168   MCInstLowering.Initialize(&MF->getContext());
 169 }
 170
 171 /// EmitFunctionBodyEnd - Targets can override this to emit stuff after
 172 /// the last basic block in the function.
 173 void XCoreAsmPrinter::emitFunctionBodyEnd() {
 174   // Emit function end directives
 175   getTargetStreamer().emitCCBottomFunction(CurrentFnSym->getName());
 176 }
 177
 178 void XCoreAsmPrinter::emitFunctionEntryLabel() {
 179   // Mark the start of the function
 180   getTargetStreamer().emitCCTopFunction(CurrentFnSym->getName());
 181   OutStreamer->emitLabel(CurrentFnSym);
 182 }
 183
 184 void XCoreAsmPrinter::
 185 printInlineJT(const MachineInstr *MI, int opNum, raw_ostream &O,
 186               const std::string &directive) {
 187   unsigned JTI = MI->getOperand(opNum).getIndex();
 188   const MachineFunction *MF = MI->getParent()->getParent();
 189   const MachineJumpTableInfo *MJTI = MF->getJumpTableInfo();
 190   const std::vector<MachineJumpTableEntry> &JT = MJTI->getJumpTables();
 191   const std::vector<MachineBasicBlock*> &JTBBs = JT[JTI].MBBs;
 192   O << "\t" << directive << " ";
 193   for (unsigned i = 0, e = JTBBs.size(); i != e; ++i) {
 194     MachineBasicBlock *MBB = JTBBs[i];
 195     if (i > 0)
 196       O << ",";
 197     MBB->getSymbol()->print(O, MAI);
 198   }
 199 }
 200
 201 void XCoreAsmPrinter::printOperand(const MachineInstr *MI, int opNum,
 202                                    raw_ostream &O) {
 203   const DataLayout &DL = getDataLayout();
 204   const MachineOperand &MO = MI->getOperand(opNum);
 205   switch (MO.getType()) {
 206   case MachineOperand::MO_Register:
 207     O << XCoreInstPrinter::getRegisterName(MO.getReg());
 208     break;
 209   case MachineOperand::MO_Immediate:
 210     O << MO.getImm();
 211     break;
 212   case MachineOperand::MO_MachineBasicBlock:
 213     MO.getMBB()->getSymbol()->print(O, MAI);
 214     break;
 215   case MachineOperand::MO_GlobalAddress:
 216     PrintSymbolOperand(MO, O);
 217     break;
 218   case MachineOperand::MO_ConstantPoolIndex:
 219     O << DL.getPrivateGlobalPrefix() << "CPI" << getFunctionNumber() << '_'
 220       << MO.getIndex();
 221     break;
 222   case MachineOperand::MO_BlockAddress:
 223     GetBlockAddressSymbol(MO.getBlockAddress())->print(O, MAI);
 224     break;
 225   default:
 226     llvm_unreachable("not implemented");
 227   }
 228 }
 229
 230 /// PrintAsmOperand - Print out an operand for an inline asm expression.
 231 ///
 232 bool XCoreAsmPrinter::PrintAsmOperand(const MachineInstr *MI, unsigned OpNo,
 233                                       const char *ExtraCode, raw_ostream &O) {
 234   // Print the operand if there is no operand modifier.
 235   if (!ExtraCode || !ExtraCode[0]) {
 236     printOperand(MI, OpNo, O);
 237     return false;
 238   }
 239
 240   // Otherwise fallback on the default implementation.
 241   return AsmPrinter::PrintAsmOperand(MI, OpNo, ExtraCode, O);
 242 }
 243
 244 bool XCoreAsmPrinter::PrintAsmMemoryOperand(const MachineInstr *MI,
 245                                             unsigned OpNum,
 246                                             const char *ExtraCode,
 247                                             raw_ostream &O) {
 248   if (ExtraCode && ExtraCode[0]) {
 249     return true; // Unknown modifier.
 250   }
 251   printOperand(MI, OpNum, O);
 252   O << '[';
 253   printOperand(MI, OpNum + 1, O);
 254   O << ']';
 255   return false;
 256 }
 257
 258 void XCoreAsmPrinter::emitInstruction(const MachineInstr *MI) {
 259   XCore_MC::verifyInstructionPredicates(MI->getOpcode(),
 260                                         getSubtargetInfo().getFeatureBits());
 261
 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" LLVM_EXTERNAL_VISIBILITY void LLVMInitializeXCoreAsmPrinter() {
 298   RegisterAsmPrinter<XCoreAsmPrinter> X(getTheXCoreTarget());
 299 }