xref: /freebsd/contrib/llvm-project/llvm/lib/Target/Sparc/Disassembler/SparcDisassembler.cpp (revision 5ca8e32633c4ffbbcd6762e5888b6a4ba0708c6c)
1 //===- SparcDisassembler.cpp - Disassembler for Sparc -----------*- C++ -*-===//
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 is part of the Sparc Disassembler.
10 //
11 //===----------------------------------------------------------------------===//
12 
13 #include "MCTargetDesc/SparcMCTargetDesc.h"
14 #include "TargetInfo/SparcTargetInfo.h"
15 #include "llvm/MC/MCAsmInfo.h"
16 #include "llvm/MC/MCContext.h"
17 #include "llvm/MC/MCDecoderOps.h"
18 #include "llvm/MC/MCDisassembler/MCDisassembler.h"
19 #include "llvm/MC/MCInst.h"
20 #include "llvm/MC/TargetRegistry.h"
21 
22 using namespace llvm;
23 
24 #define DEBUG_TYPE "sparc-disassembler"
25 
26 typedef MCDisassembler::DecodeStatus DecodeStatus;
27 
28 namespace {
29 
30 /// A disassembler class for Sparc.
31 class SparcDisassembler : public MCDisassembler {
32 public:
33   SparcDisassembler(const MCSubtargetInfo &STI, MCContext &Ctx)
34       : MCDisassembler(STI, Ctx) {}
35   virtual ~SparcDisassembler() = default;
36 
37   DecodeStatus getInstruction(MCInst &Instr, uint64_t &Size,
38                               ArrayRef<uint8_t> Bytes, uint64_t Address,
39                               raw_ostream &CStream) const override;
40 };
41 }
42 
43 static MCDisassembler *createSparcDisassembler(const Target &T,
44                                                const MCSubtargetInfo &STI,
45                                                MCContext &Ctx) {
46   return new SparcDisassembler(STI, Ctx);
47 }
48 
49 
50 extern "C" LLVM_EXTERNAL_VISIBILITY void LLVMInitializeSparcDisassembler() {
51   // Register the disassembler.
52   TargetRegistry::RegisterMCDisassembler(getTheSparcTarget(),
53                                          createSparcDisassembler);
54   TargetRegistry::RegisterMCDisassembler(getTheSparcV9Target(),
55                                          createSparcDisassembler);
56   TargetRegistry::RegisterMCDisassembler(getTheSparcelTarget(),
57                                          createSparcDisassembler);
58 }
59 
60 static const unsigned IntRegDecoderTable[] = {
61   SP::G0,  SP::G1,  SP::G2,  SP::G3,
62   SP::G4,  SP::G5,  SP::G6,  SP::G7,
63   SP::O0,  SP::O1,  SP::O2,  SP::O3,
64   SP::O4,  SP::O5,  SP::O6,  SP::O7,
65   SP::L0,  SP::L1,  SP::L2,  SP::L3,
66   SP::L4,  SP::L5,  SP::L6,  SP::L7,
67   SP::I0,  SP::I1,  SP::I2,  SP::I3,
68   SP::I4,  SP::I5,  SP::I6,  SP::I7 };
69 
70 static const unsigned FPRegDecoderTable[] = {
71   SP::F0,   SP::F1,   SP::F2,   SP::F3,
72   SP::F4,   SP::F5,   SP::F6,   SP::F7,
73   SP::F8,   SP::F9,   SP::F10,  SP::F11,
74   SP::F12,  SP::F13,  SP::F14,  SP::F15,
75   SP::F16,  SP::F17,  SP::F18,  SP::F19,
76   SP::F20,  SP::F21,  SP::F22,  SP::F23,
77   SP::F24,  SP::F25,  SP::F26,  SP::F27,
78   SP::F28,  SP::F29,  SP::F30,  SP::F31 };
79 
80 static const unsigned DFPRegDecoderTable[] = {
81   SP::D0,   SP::D16,  SP::D1,   SP::D17,
82   SP::D2,   SP::D18,  SP::D3,   SP::D19,
83   SP::D4,   SP::D20,  SP::D5,   SP::D21,
84   SP::D6,   SP::D22,  SP::D7,   SP::D23,
85   SP::D8,   SP::D24,  SP::D9,   SP::D25,
86   SP::D10,  SP::D26,  SP::D11,  SP::D27,
87   SP::D12,  SP::D28,  SP::D13,  SP::D29,
88   SP::D14,  SP::D30,  SP::D15,  SP::D31 };
89 
90 static const unsigned QFPRegDecoderTable[] = {
91   SP::Q0,  SP::Q8,   ~0U,  ~0U,
92   SP::Q1,  SP::Q9,   ~0U,  ~0U,
93   SP::Q2,  SP::Q10,  ~0U,  ~0U,
94   SP::Q3,  SP::Q11,  ~0U,  ~0U,
95   SP::Q4,  SP::Q12,  ~0U,  ~0U,
96   SP::Q5,  SP::Q13,  ~0U,  ~0U,
97   SP::Q6,  SP::Q14,  ~0U,  ~0U,
98   SP::Q7,  SP::Q15,  ~0U,  ~0U } ;
99 
100 static const unsigned FCCRegDecoderTable[] = {
101   SP::FCC0, SP::FCC1, SP::FCC2, SP::FCC3 };
102 
103 static const unsigned ASRRegDecoderTable[] = {
104   SP::Y,     SP::ASR1,  SP::ASR2,  SP::ASR3,
105   SP::ASR4,  SP::ASR5,  SP::ASR6,  SP::ASR7,
106   SP::ASR8,  SP::ASR9,  SP::ASR10, SP::ASR11,
107   SP::ASR12, SP::ASR13, SP::ASR14, SP::ASR15,
108   SP::ASR16, SP::ASR17, SP::ASR18, SP::ASR19,
109   SP::ASR20, SP::ASR21, SP::ASR22, SP::ASR23,
110   SP::ASR24, SP::ASR25, SP::ASR26, SP::ASR27,
111   SP::ASR28, SP::ASR29, SP::ASR30, SP::ASR31};
112 
113 static const unsigned PRRegDecoderTable[] = {
114   SP::TPC, SP::TNPC, SP::TSTATE, SP::TT, SP::TICK, SP::TBA, SP::PSTATE,
115   SP::TL, SP::PIL, SP::CWP, SP::CANSAVE, SP::CANRESTORE, SP::CLEANWIN,
116   SP::OTHERWIN, SP::WSTATE, SP::PC
117 };
118 
119 static const uint16_t IntPairDecoderTable[] = {
120   SP::G0_G1, SP::G2_G3, SP::G4_G5, SP::G6_G7,
121   SP::O0_O1, SP::O2_O3, SP::O4_O5, SP::O6_O7,
122   SP::L0_L1, SP::L2_L3, SP::L4_L5, SP::L6_L7,
123   SP::I0_I1, SP::I2_I3, SP::I4_I5, SP::I6_I7,
124 };
125 
126 static const unsigned CPRegDecoderTable[] = {
127   SP::C0,  SP::C1,  SP::C2,  SP::C3,
128   SP::C4,  SP::C5,  SP::C6,  SP::C7,
129   SP::C8,  SP::C9,  SP::C10, SP::C11,
130   SP::C12, SP::C13, SP::C14, SP::C15,
131   SP::C16, SP::C17, SP::C18, SP::C19,
132   SP::C20, SP::C21, SP::C22, SP::C23,
133   SP::C24, SP::C25, SP::C26, SP::C27,
134   SP::C28, SP::C29, SP::C30, SP::C31
135 };
136 
137 
138 static const uint16_t CPPairDecoderTable[] = {
139   SP::C0_C1,   SP::C2_C3,   SP::C4_C5,   SP::C6_C7,
140   SP::C8_C9,   SP::C10_C11, SP::C12_C13, SP::C14_C15,
141   SP::C16_C17, SP::C18_C19, SP::C20_C21, SP::C22_C23,
142   SP::C24_C25, SP::C26_C27, SP::C28_C29, SP::C30_C31
143 };
144 
145 static DecodeStatus DecodeIntRegsRegisterClass(MCInst &Inst, unsigned RegNo,
146                                                uint64_t Address,
147                                                const MCDisassembler *Decoder) {
148   if (RegNo > 31)
149     return MCDisassembler::Fail;
150   unsigned Reg = IntRegDecoderTable[RegNo];
151   Inst.addOperand(MCOperand::createReg(Reg));
152   return MCDisassembler::Success;
153 }
154 
155 static DecodeStatus DecodeI64RegsRegisterClass(MCInst &Inst, unsigned RegNo,
156                                                uint64_t Address,
157                                                const MCDisassembler *Decoder) {
158   return DecodeIntRegsRegisterClass(Inst, RegNo, Address, Decoder);
159 }
160 
161 // This is used for the type "ptr_rc", which is either IntRegs or I64Regs
162 // depending on SparcRegisterInfo::getPointerRegClass.
163 static DecodeStatus DecodePointerLikeRegClass0(MCInst &Inst, unsigned RegNo,
164                                                uint64_t Address,
165                                                const MCDisassembler *Decoder) {
166   return DecodeIntRegsRegisterClass(Inst, RegNo, Address, Decoder);
167 }
168 
169 static DecodeStatus DecodeFPRegsRegisterClass(MCInst &Inst, unsigned RegNo,
170                                               uint64_t Address,
171                                               const MCDisassembler *Decoder) {
172   if (RegNo > 31)
173     return MCDisassembler::Fail;
174   unsigned Reg = FPRegDecoderTable[RegNo];
175   Inst.addOperand(MCOperand::createReg(Reg));
176   return MCDisassembler::Success;
177 }
178 
179 static DecodeStatus DecodeDFPRegsRegisterClass(MCInst &Inst, unsigned RegNo,
180                                                uint64_t Address,
181                                                const MCDisassembler *Decoder) {
182   if (RegNo > 31)
183     return MCDisassembler::Fail;
184   unsigned Reg = DFPRegDecoderTable[RegNo];
185   Inst.addOperand(MCOperand::createReg(Reg));
186   return MCDisassembler::Success;
187 }
188 
189 static DecodeStatus DecodeQFPRegsRegisterClass(MCInst &Inst, unsigned RegNo,
190                                                uint64_t Address,
191                                                const MCDisassembler *Decoder) {
192   if (RegNo > 31)
193     return MCDisassembler::Fail;
194 
195   unsigned Reg = QFPRegDecoderTable[RegNo];
196   if (Reg == ~0U)
197     return MCDisassembler::Fail;
198   Inst.addOperand(MCOperand::createReg(Reg));
199   return MCDisassembler::Success;
200 }
201 
202 static DecodeStatus
203 DecodeCoprocRegsRegisterClass(MCInst &Inst, unsigned RegNo, uint64_t Address,
204                               const MCDisassembler *Decoder) {
205   if (RegNo > 31)
206     return MCDisassembler::Fail;
207   unsigned Reg = CPRegDecoderTable[RegNo];
208   Inst.addOperand(MCOperand::createReg(Reg));
209   return MCDisassembler::Success;
210 }
211 
212 static DecodeStatus DecodeFCCRegsRegisterClass(MCInst &Inst, unsigned RegNo,
213                                                uint64_t Address,
214                                                const MCDisassembler *Decoder) {
215   if (RegNo > 3)
216     return MCDisassembler::Fail;
217   Inst.addOperand(MCOperand::createReg(FCCRegDecoderTable[RegNo]));
218   return MCDisassembler::Success;
219 }
220 
221 static DecodeStatus DecodeASRRegsRegisterClass(MCInst &Inst, unsigned RegNo,
222                                                uint64_t Address,
223                                                const MCDisassembler *Decoder) {
224   if (RegNo > 31)
225     return MCDisassembler::Fail;
226   Inst.addOperand(MCOperand::createReg(ASRRegDecoderTable[RegNo]));
227   return MCDisassembler::Success;
228 }
229 
230 static DecodeStatus DecodePRRegsRegisterClass(MCInst &Inst, unsigned RegNo,
231                                               uint64_t Address,
232                                               const MCDisassembler *Decoder) {
233   if (RegNo >= std::size(PRRegDecoderTable))
234     return MCDisassembler::Fail;
235   Inst.addOperand(MCOperand::createReg(PRRegDecoderTable[RegNo]));
236   return MCDisassembler::Success;
237 }
238 
239 static DecodeStatus DecodeIntPairRegisterClass(MCInst &Inst, unsigned RegNo,
240                                                uint64_t Address,
241                                                const MCDisassembler *Decoder) {
242   DecodeStatus S = MCDisassembler::Success;
243 
244   if (RegNo > 31)
245     return MCDisassembler::Fail;
246 
247   if ((RegNo & 1))
248     S = MCDisassembler::SoftFail;
249 
250   unsigned RegisterPair = IntPairDecoderTable[RegNo/2];
251   Inst.addOperand(MCOperand::createReg(RegisterPair));
252   return S;
253 }
254 
255 static DecodeStatus
256 DecodeCoprocPairRegisterClass(MCInst &Inst, unsigned RegNo, uint64_t Address,
257                               const MCDisassembler *Decoder) {
258   if (RegNo > 31)
259     return MCDisassembler::Fail;
260 
261   unsigned RegisterPair = CPPairDecoderTable[RegNo/2];
262   Inst.addOperand(MCOperand::createReg(RegisterPair));
263   return MCDisassembler::Success;
264 }
265 
266 static DecodeStatus DecodeCall(MCInst &Inst, unsigned insn, uint64_t Address,
267                                const MCDisassembler *Decoder);
268 static DecodeStatus DecodeSIMM13(MCInst &Inst, unsigned insn, uint64_t Address,
269                                  const MCDisassembler *Decoder);
270 
271 #include "SparcGenDisassemblerTables.inc"
272 
273 /// Read four bytes from the ArrayRef and return 32 bit word.
274 static DecodeStatus readInstruction32(ArrayRef<uint8_t> Bytes, uint64_t Address,
275                                       uint64_t &Size, uint32_t &Insn,
276                                       bool IsLittleEndian) {
277   // We want to read exactly 4 Bytes of data.
278   if (Bytes.size() < 4) {
279     Size = 0;
280     return MCDisassembler::Fail;
281   }
282 
283   Insn = IsLittleEndian
284              ? (Bytes[0] << 0) | (Bytes[1] << 8) | (Bytes[2] << 16) |
285                    (Bytes[3] << 24)
286              : (Bytes[3] << 0) | (Bytes[2] << 8) | (Bytes[1] << 16) |
287                    (Bytes[0] << 24);
288 
289   return MCDisassembler::Success;
290 }
291 
292 DecodeStatus SparcDisassembler::getInstruction(MCInst &Instr, uint64_t &Size,
293                                                ArrayRef<uint8_t> Bytes,
294                                                uint64_t Address,
295                                                raw_ostream &CStream) const {
296   uint32_t Insn;
297   bool isLittleEndian = getContext().getAsmInfo()->isLittleEndian();
298   DecodeStatus Result =
299       readInstruction32(Bytes, Address, Size, Insn, isLittleEndian);
300   if (Result == MCDisassembler::Fail)
301     return MCDisassembler::Fail;
302 
303   // Calling the auto-generated decoder function.
304 
305   if (STI.hasFeature(Sparc::FeatureV9))
306   {
307     Result = decodeInstruction(DecoderTableSparcV932, Instr, Insn, Address, this, STI);
308   }
309   else
310   {
311     Result = decodeInstruction(DecoderTableSparcV832, Instr, Insn, Address, this, STI);
312   }
313   if (Result != MCDisassembler::Fail)
314     return Result;
315 
316   Result =
317       decodeInstruction(DecoderTableSparc32, Instr, Insn, Address, this, STI);
318 
319   if (Result != MCDisassembler::Fail) {
320     Size = 4;
321     return Result;
322   }
323 
324   return MCDisassembler::Fail;
325 }
326 
327 static bool tryAddingSymbolicOperand(int64_t Value, bool isBranch,
328                                      uint64_t Address, uint64_t Offset,
329                                      uint64_t Width, MCInst &MI,
330                                      const MCDisassembler *Decoder) {
331   return Decoder->tryAddingSymbolicOperand(MI, Value, Address, isBranch, Offset,
332                                            Width, /*InstSize=*/4);
333 }
334 
335 static DecodeStatus DecodeCall(MCInst &MI, unsigned insn, uint64_t Address,
336                                const MCDisassembler *Decoder) {
337   unsigned tgt = fieldFromInstruction(insn, 0, 30);
338   tgt <<= 2;
339   if (!tryAddingSymbolicOperand(tgt+Address, false, Address,
340                                 0, 30, MI, Decoder))
341     MI.addOperand(MCOperand::createImm(tgt));
342   return MCDisassembler::Success;
343 }
344 
345 static DecodeStatus DecodeSIMM13(MCInst &MI, unsigned insn, uint64_t Address,
346                                  const MCDisassembler *Decoder) {
347   unsigned tgt = SignExtend32<13>(fieldFromInstruction(insn, 0, 13));
348   MI.addOperand(MCOperand::createImm(tgt));
349   return MCDisassembler::Success;
350 }
351