lib/Target/Hexagon/Disassembler/HexagonDisassembler.cpp

   1 //===-- HexagonDisassembler.cpp - Disassembler for Hexagon ISA ------------===//\r
   2 //\r
   3 //                     The LLVM Compiler Infrastructure\r
   4 //\r
   5 // This file is distributed under the University of Illinois Open Source\r
   6 // License. See LICENSE.TXT for details.\r
   7 //\r
   8 //===----------------------------------------------------------------------===//\r
   9 \r
  10 #include "MCTargetDesc/HexagonBaseInfo.h"\r
  11 #include "MCTargetDesc/HexagonMCTargetDesc.h"\r
  12 \r
  13 #include "llvm/MC/MCContext.h"\r
  14 #include "llvm/MC/MCDisassembler.h"\r
  15 #include "llvm/MC/MCExpr.h"\r
  16 #include "llvm/MC/MCFixedLenDisassembler.h"\r
  17 #include "llvm/MC/MCInst.h"\r
  18 #include "llvm/MC/MCInstrDesc.h"\r
  19 #include "llvm/MC/MCSubtargetInfo.h"\r
  20 #include "llvm/Support/Debug.h"\r
  21 #include "llvm/Support/ErrorHandling.h"\r
  22 #include "llvm/Support/LEB128.h"\r
  23 #include "llvm/Support/MemoryObject.h"\r
  24 #include "llvm/Support/raw_ostream.h"\r
  25 #include "llvm/Support/TargetRegistry.h"\r
  26 #include "llvm/Support/Endian.h"\r
  27 \r
  28 #include <vector>\r
  29 #include <array>\r
  30 \r
  31 using namespace llvm;\r
  32 \r
  33 #define DEBUG_TYPE "hexagon-disassembler"\r
  34 \r
  35 // Pull DecodeStatus and its enum values into the global namespace.\r
  36 typedef llvm::MCDisassembler::DecodeStatus DecodeStatus;\r
  37 \r
  38 namespace {\r
  39 /// \brief Hexagon disassembler for all Hexagon platforms.\r
  40 class HexagonDisassembler : public MCDisassembler {\r
  41 public:\r
  42   HexagonDisassembler(MCSubtargetInfo const &STI, MCContext &Ctx)\r
  43       : MCDisassembler(STI, Ctx) {}\r
  44 \r
  45   DecodeStatus getInstruction(MCInst &instr, uint64_t &size,\r
  46                               MemoryObject const &region, uint64_t address,\r
  47                               raw_ostream &vStream, raw_ostream &cStream) const override;\r
  48 };\r
  49 }\r
  50 \r
  51 static const uint16_t IntRegDecoderTable[] = {\r
  52     Hexagon::R0,  Hexagon::R1,  Hexagon::R2,  Hexagon::R3,  Hexagon::R4,\r
  53     Hexagon::R5,  Hexagon::R6,  Hexagon::R7,  Hexagon::R8,  Hexagon::R9,\r
  54     Hexagon::R10, Hexagon::R11, Hexagon::R12, Hexagon::R13, Hexagon::R14,\r
  55     Hexagon::R15, Hexagon::R16, Hexagon::R17, Hexagon::R18, Hexagon::R19,\r
  56     Hexagon::R20, Hexagon::R21, Hexagon::R22, Hexagon::R23, Hexagon::R24,\r
  57     Hexagon::R25, Hexagon::R26, Hexagon::R27, Hexagon::R28, Hexagon::R29,\r
  58     Hexagon::R30, Hexagon::R31};\r
  59 \r
  60 static const uint16_t PredRegDecoderTable[] = {Hexagon::P0, Hexagon::P1,\r
  61                                                Hexagon::P2, Hexagon::P3};\r
  62 \r
  63 static DecodeStatus DecodeIntRegsRegisterClass(MCInst &Inst, unsigned RegNo,\r
  64                                                uint64_t /*Address*/,\r
  65                                                void const *Decoder) {\r
  66   if (RegNo > 31)\r
  67     return MCDisassembler::Fail;\r
  68 \r
  69   unsigned Register = IntRegDecoderTable[RegNo];\r
  70   Inst.addOperand(MCOperand::CreateReg(Register));\r
  71   return MCDisassembler::Success;\r
  72 }\r
  73 \r
  74 static DecodeStatus DecodePredRegsRegisterClass(MCInst &Inst, unsigned RegNo,\r
  75                                                 uint64_t /*Address*/,\r
  76                                                 void const *Decoder) {\r
  77   if (RegNo > 3)\r
  78     return MCDisassembler::Fail;\r
  79 \r
  80   unsigned Register = PredRegDecoderTable[RegNo];\r
  81   Inst.addOperand(MCOperand::CreateReg(Register));\r
  82   return MCDisassembler::Success;\r
  83 }\r
  84 \r
  85 #include "HexagonGenDisassemblerTables.inc"\r
  86 \r
  87 static MCDisassembler *createHexagonDisassembler(Target const &T,\r
  88                                                  MCSubtargetInfo const &STI,\r
  89                                                  MCContext &Ctx) {\r
  90   return new HexagonDisassembler(STI, Ctx);\r
  91 }\r
  92 \r
  93 extern "C" void LLVMInitializeHexagonDisassembler() {\r
  94   TargetRegistry::RegisterMCDisassembler(TheHexagonTarget,\r
  95                                          createHexagonDisassembler);\r
  96 }\r
  97 \r
  98 DecodeStatus HexagonDisassembler::getInstruction(MCInst &MI, uint64_t &Size,\r
  99                                                  MemoryObject const &Region,\r
 100                                                  uint64_t Address,\r
 101                                                  raw_ostream &os,\r
 102                                                  raw_ostream &cs) const {\r
 103   std::array<uint8_t, 4> Bytes;\r
 104   Size = 4;\r
 105   if (Region.readBytes(Address, Bytes.size(), Bytes.data()) == -1) {\r
 106     return MCDisassembler::Fail;\r
 107   }\r
 108   uint32_t insn =\r
 109       llvm::support::endian::read<uint32_t, llvm::support::little,\r
 110                                   llvm::support::unaligned>(Bytes.data());\r
 111 \r
 112   // Remove parse bits.\r
 113   insn &= ~static_cast<uint32_t>(HexagonII::InstParseBits::INST_PARSE_MASK);\r
 114   return decodeInstruction(DecoderTable32, MI, insn, Address, this, STI);\r
 115 }\r