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