xref: /llvm-project/llvm/lib/Target/PowerPC/Disassembler/PPCDisassembler.cpp (revision 11049f8f07330c30c689d54ed91d63909b360cf2)
1 //===------ PPCDisassembler.cpp - Disassembler for PowerPC ------*- C++ -*-===//
2 //
3 //                     The LLVM Compiler Infrastructure
4 //
5 // This file is distributed under the University of Illinois Open Source
6 // License. See LICENSE.TXT for details.
7 //
8 //===----------------------------------------------------------------------===//
9 
10 #include "PPC.h"
11 #include "llvm/MC/MCDisassembler/MCDisassembler.h"
12 #include "llvm/MC/MCFixedLenDisassembler.h"
13 #include "llvm/MC/MCInst.h"
14 #include "llvm/MC/MCSubtargetInfo.h"
15 #include "llvm/Support/Endian.h"
16 #include "llvm/Support/TargetRegistry.h"
17 
18 using namespace llvm;
19 
20 #define DEBUG_TYPE "ppc-disassembler"
21 
22 typedef MCDisassembler::DecodeStatus DecodeStatus;
23 
24 namespace {
25 class PPCDisassembler : public MCDisassembler {
26   bool IsLittleEndian;
27 
28 public:
29   PPCDisassembler(const MCSubtargetInfo &STI, MCContext &Ctx,
30                   bool IsLittleEndian)
31       : MCDisassembler(STI, Ctx), IsLittleEndian(IsLittleEndian) {}
32 
33   DecodeStatus getInstruction(MCInst &Instr, uint64_t &Size,
34                               ArrayRef<uint8_t> Bytes, uint64_t Address,
35                               raw_ostream &VStream,
36                               raw_ostream &CStream) const override;
37 };
38 } // end anonymous namespace
39 
40 static MCDisassembler *createPPCDisassembler(const Target &T,
41                                              const MCSubtargetInfo &STI,
42                                              MCContext &Ctx) {
43   return new PPCDisassembler(STI, Ctx, /*IsLittleEndian=*/false);
44 }
45 
46 static MCDisassembler *createPPCLEDisassembler(const Target &T,
47                                                const MCSubtargetInfo &STI,
48                                                MCContext &Ctx) {
49   return new PPCDisassembler(STI, Ctx, /*IsLittleEndian=*/true);
50 }
51 
52 extern "C" void LLVMInitializePowerPCDisassembler() {
53   // Register the disassembler for each target.
54   TargetRegistry::RegisterMCDisassembler(ThePPC32Target,
55                                          createPPCDisassembler);
56   TargetRegistry::RegisterMCDisassembler(ThePPC64Target,
57                                          createPPCDisassembler);
58   TargetRegistry::RegisterMCDisassembler(ThePPC64LETarget,
59                                          createPPCLEDisassembler);
60 }
61 
62 // FIXME: These can be generated by TableGen from the existing register
63 // encoding values!
64 
65 static const unsigned CRRegs[] = {
66   PPC::CR0, PPC::CR1, PPC::CR2, PPC::CR3,
67   PPC::CR4, PPC::CR5, PPC::CR6, PPC::CR7
68 };
69 
70 static const unsigned CRBITRegs[] = {
71   PPC::CR0LT, PPC::CR0GT, PPC::CR0EQ, PPC::CR0UN,
72   PPC::CR1LT, PPC::CR1GT, PPC::CR1EQ, PPC::CR1UN,
73   PPC::CR2LT, PPC::CR2GT, PPC::CR2EQ, PPC::CR2UN,
74   PPC::CR3LT, PPC::CR3GT, PPC::CR3EQ, PPC::CR3UN,
75   PPC::CR4LT, PPC::CR4GT, PPC::CR4EQ, PPC::CR4UN,
76   PPC::CR5LT, PPC::CR5GT, PPC::CR5EQ, PPC::CR5UN,
77   PPC::CR6LT, PPC::CR6GT, PPC::CR6EQ, PPC::CR6UN,
78   PPC::CR7LT, PPC::CR7GT, PPC::CR7EQ, PPC::CR7UN
79 };
80 
81 static const unsigned FRegs[] = {
82   PPC::F0, PPC::F1, PPC::F2, PPC::F3,
83   PPC::F4, PPC::F5, PPC::F6, PPC::F7,
84   PPC::F8, PPC::F9, PPC::F10, PPC::F11,
85   PPC::F12, PPC::F13, PPC::F14, PPC::F15,
86   PPC::F16, PPC::F17, PPC::F18, PPC::F19,
87   PPC::F20, PPC::F21, PPC::F22, PPC::F23,
88   PPC::F24, PPC::F25, PPC::F26, PPC::F27,
89   PPC::F28, PPC::F29, PPC::F30, PPC::F31
90 };
91 
92 static const unsigned VFRegs[] = {
93   PPC::VF0, PPC::VF1, PPC::VF2, PPC::VF3,
94   PPC::VF4, PPC::VF5, PPC::VF6, PPC::VF7,
95   PPC::VF8, PPC::VF9, PPC::VF10, PPC::VF11,
96   PPC::VF12, PPC::VF13, PPC::VF14, PPC::VF15,
97   PPC::VF16, PPC::VF17, PPC::VF18, PPC::VF19,
98   PPC::VF20, PPC::VF21, PPC::VF22, PPC::VF23,
99   PPC::VF24, PPC::VF25, PPC::VF26, PPC::VF27,
100   PPC::VF28, PPC::VF29, PPC::VF30, PPC::VF31
101 };
102 
103 static const unsigned VRegs[] = {
104   PPC::V0, PPC::V1, PPC::V2, PPC::V3,
105   PPC::V4, PPC::V5, PPC::V6, PPC::V7,
106   PPC::V8, PPC::V9, PPC::V10, PPC::V11,
107   PPC::V12, PPC::V13, PPC::V14, PPC::V15,
108   PPC::V16, PPC::V17, PPC::V18, PPC::V19,
109   PPC::V20, PPC::V21, PPC::V22, PPC::V23,
110   PPC::V24, PPC::V25, PPC::V26, PPC::V27,
111   PPC::V28, PPC::V29, PPC::V30, PPC::V31
112 };
113 
114 static const unsigned VSRegs[] = {
115   PPC::VSL0, PPC::VSL1, PPC::VSL2, PPC::VSL3,
116   PPC::VSL4, PPC::VSL5, PPC::VSL6, PPC::VSL7,
117   PPC::VSL8, PPC::VSL9, PPC::VSL10, PPC::VSL11,
118   PPC::VSL12, PPC::VSL13, PPC::VSL14, PPC::VSL15,
119   PPC::VSL16, PPC::VSL17, PPC::VSL18, PPC::VSL19,
120   PPC::VSL20, PPC::VSL21, PPC::VSL22, PPC::VSL23,
121   PPC::VSL24, PPC::VSL25, PPC::VSL26, PPC::VSL27,
122   PPC::VSL28, PPC::VSL29, PPC::VSL30, PPC::VSL31,
123 
124   PPC::V0, PPC::V1, PPC::V2, PPC::V3,
125   PPC::V4, PPC::V5, PPC::V6, PPC::V7,
126   PPC::V8, PPC::V9, PPC::V10, PPC::V11,
127   PPC::V12, PPC::V13, PPC::V14, PPC::V15,
128   PPC::V16, PPC::V17, PPC::V18, PPC::V19,
129   PPC::V20, PPC::V21, PPC::V22, PPC::V23,
130   PPC::V24, PPC::V25, PPC::V26, PPC::V27,
131   PPC::V28, PPC::V29, PPC::V30, PPC::V31
132 };
133 
134 static const unsigned VSFRegs[] = {
135   PPC::F0, PPC::F1, PPC::F2, PPC::F3,
136   PPC::F4, PPC::F5, PPC::F6, PPC::F7,
137   PPC::F8, PPC::F9, PPC::F10, PPC::F11,
138   PPC::F12, PPC::F13, PPC::F14, PPC::F15,
139   PPC::F16, PPC::F17, PPC::F18, PPC::F19,
140   PPC::F20, PPC::F21, PPC::F22, PPC::F23,
141   PPC::F24, PPC::F25, PPC::F26, PPC::F27,
142   PPC::F28, PPC::F29, PPC::F30, PPC::F31,
143 
144   PPC::VF0, PPC::VF1, PPC::VF2, PPC::VF3,
145   PPC::VF4, PPC::VF5, PPC::VF6, PPC::VF7,
146   PPC::VF8, PPC::VF9, PPC::VF10, PPC::VF11,
147   PPC::VF12, PPC::VF13, PPC::VF14, PPC::VF15,
148   PPC::VF16, PPC::VF17, PPC::VF18, PPC::VF19,
149   PPC::VF20, PPC::VF21, PPC::VF22, PPC::VF23,
150   PPC::VF24, PPC::VF25, PPC::VF26, PPC::VF27,
151   PPC::VF28, PPC::VF29, PPC::VF30, PPC::VF31
152 };
153 
154 static const unsigned VSSRegs[] = {
155   PPC::F0, PPC::F1, PPC::F2, PPC::F3,
156   PPC::F4, PPC::F5, PPC::F6, PPC::F7,
157   PPC::F8, PPC::F9, PPC::F10, PPC::F11,
158   PPC::F12, PPC::F13, PPC::F14, PPC::F15,
159   PPC::F16, PPC::F17, PPC::F18, PPC::F19,
160   PPC::F20, PPC::F21, PPC::F22, PPC::F23,
161   PPC::F24, PPC::F25, PPC::F26, PPC::F27,
162   PPC::F28, PPC::F29, PPC::F30, PPC::F31,
163 
164   PPC::VF0, PPC::VF1, PPC::VF2, PPC::VF3,
165   PPC::VF4, PPC::VF5, PPC::VF6, PPC::VF7,
166   PPC::VF8, PPC::VF9, PPC::VF10, PPC::VF11,
167   PPC::VF12, PPC::VF13, PPC::VF14, PPC::VF15,
168   PPC::VF16, PPC::VF17, PPC::VF18, PPC::VF19,
169   PPC::VF20, PPC::VF21, PPC::VF22, PPC::VF23,
170   PPC::VF24, PPC::VF25, PPC::VF26, PPC::VF27,
171   PPC::VF28, PPC::VF29, PPC::VF30, PPC::VF31
172 };
173 
174 static const unsigned GPRegs[] = {
175   PPC::R0, PPC::R1, PPC::R2, PPC::R3,
176   PPC::R4, PPC::R5, PPC::R6, PPC::R7,
177   PPC::R8, PPC::R9, PPC::R10, PPC::R11,
178   PPC::R12, PPC::R13, PPC::R14, PPC::R15,
179   PPC::R16, PPC::R17, PPC::R18, PPC::R19,
180   PPC::R20, PPC::R21, PPC::R22, PPC::R23,
181   PPC::R24, PPC::R25, PPC::R26, PPC::R27,
182   PPC::R28, PPC::R29, PPC::R30, PPC::R31
183 };
184 
185 static const unsigned GP0Regs[] = {
186   PPC::ZERO, PPC::R1, PPC::R2, PPC::R3,
187   PPC::R4, PPC::R5, PPC::R6, PPC::R7,
188   PPC::R8, PPC::R9, PPC::R10, PPC::R11,
189   PPC::R12, PPC::R13, PPC::R14, PPC::R15,
190   PPC::R16, PPC::R17, PPC::R18, PPC::R19,
191   PPC::R20, PPC::R21, PPC::R22, PPC::R23,
192   PPC::R24, PPC::R25, PPC::R26, PPC::R27,
193   PPC::R28, PPC::R29, PPC::R30, PPC::R31
194 };
195 
196 static const unsigned G8Regs[] = {
197   PPC::X0, PPC::X1, PPC::X2, PPC::X3,
198   PPC::X4, PPC::X5, PPC::X6, PPC::X7,
199   PPC::X8, PPC::X9, PPC::X10, PPC::X11,
200   PPC::X12, PPC::X13, PPC::X14, PPC::X15,
201   PPC::X16, PPC::X17, PPC::X18, PPC::X19,
202   PPC::X20, PPC::X21, PPC::X22, PPC::X23,
203   PPC::X24, PPC::X25, PPC::X26, PPC::X27,
204   PPC::X28, PPC::X29, PPC::X30, PPC::X31
205 };
206 
207 static const unsigned QFRegs[] = {
208   PPC::QF0, PPC::QF1, PPC::QF2, PPC::QF3,
209   PPC::QF4, PPC::QF5, PPC::QF6, PPC::QF7,
210   PPC::QF8, PPC::QF9, PPC::QF10, PPC::QF11,
211   PPC::QF12, PPC::QF13, PPC::QF14, PPC::QF15,
212   PPC::QF16, PPC::QF17, PPC::QF18, PPC::QF19,
213   PPC::QF20, PPC::QF21, PPC::QF22, PPC::QF23,
214   PPC::QF24, PPC::QF25, PPC::QF26, PPC::QF27,
215   PPC::QF28, PPC::QF29, PPC::QF30, PPC::QF31
216 };
217 
218 template <std::size_t N>
219 static DecodeStatus decodeRegisterClass(MCInst &Inst, uint64_t RegNo,
220                                         const unsigned (&Regs)[N]) {
221   assert(RegNo < N && "Invalid register number");
222   Inst.addOperand(MCOperand::createReg(Regs[RegNo]));
223   return MCDisassembler::Success;
224 }
225 
226 static DecodeStatus DecodeCRRCRegisterClass(MCInst &Inst, uint64_t RegNo,
227                                             uint64_t Address,
228                                             const void *Decoder) {
229   return decodeRegisterClass(Inst, RegNo, CRRegs);
230 }
231 
232 static DecodeStatus DecodeCRRC0RegisterClass(MCInst &Inst, uint64_t RegNo,
233                                             uint64_t Address,
234                                             const void *Decoder) {
235   return decodeRegisterClass(Inst, RegNo, CRRegs);
236 }
237 
238 static DecodeStatus DecodeCRBITRCRegisterClass(MCInst &Inst, uint64_t RegNo,
239                                             uint64_t Address,
240                                             const void *Decoder) {
241   return decodeRegisterClass(Inst, RegNo, CRBITRegs);
242 }
243 
244 static DecodeStatus DecodeF4RCRegisterClass(MCInst &Inst, uint64_t RegNo,
245                                             uint64_t Address,
246                                             const void *Decoder) {
247   return decodeRegisterClass(Inst, RegNo, FRegs);
248 }
249 
250 static DecodeStatus DecodeF8RCRegisterClass(MCInst &Inst, uint64_t RegNo,
251                                             uint64_t Address,
252                                             const void *Decoder) {
253   return decodeRegisterClass(Inst, RegNo, FRegs);
254 }
255 
256 static DecodeStatus DecodeVFRCRegisterClass(MCInst &Inst, uint64_t RegNo,
257                                             uint64_t Address,
258                                             const void *Decoder) {
259   return decodeRegisterClass(Inst, RegNo, VFRegs);
260 }
261 
262 static DecodeStatus DecodeVRRCRegisterClass(MCInst &Inst, uint64_t RegNo,
263                                             uint64_t Address,
264                                             const void *Decoder) {
265   return decodeRegisterClass(Inst, RegNo, VRegs);
266 }
267 
268 static DecodeStatus DecodeVSRCRegisterClass(MCInst &Inst, uint64_t RegNo,
269                                             uint64_t Address,
270                                             const void *Decoder) {
271   return decodeRegisterClass(Inst, RegNo, VSRegs);
272 }
273 
274 static DecodeStatus DecodeVSFRCRegisterClass(MCInst &Inst, uint64_t RegNo,
275                                             uint64_t Address,
276                                             const void *Decoder) {
277   return decodeRegisterClass(Inst, RegNo, VSFRegs);
278 }
279 
280 static DecodeStatus DecodeVSSRCRegisterClass(MCInst &Inst, uint64_t RegNo,
281                                             uint64_t Address,
282                                             const void *Decoder) {
283   return decodeRegisterClass(Inst, RegNo, VSSRegs);
284 }
285 
286 static DecodeStatus DecodeGPRCRegisterClass(MCInst &Inst, uint64_t RegNo,
287                                             uint64_t Address,
288                                             const void *Decoder) {
289   return decodeRegisterClass(Inst, RegNo, GPRegs);
290 }
291 
292 static DecodeStatus DecodeGPRC_NOR0RegisterClass(MCInst &Inst, uint64_t RegNo,
293                                             uint64_t Address,
294                                             const void *Decoder) {
295   return decodeRegisterClass(Inst, RegNo, GP0Regs);
296 }
297 
298 static DecodeStatus DecodeG8RCRegisterClass(MCInst &Inst, uint64_t RegNo,
299                                             uint64_t Address,
300                                             const void *Decoder) {
301   return decodeRegisterClass(Inst, RegNo, G8Regs);
302 }
303 
304 #define DecodePointerLikeRegClass0 DecodeGPRCRegisterClass
305 #define DecodePointerLikeRegClass1 DecodeGPRC_NOR0RegisterClass
306 
307 static DecodeStatus DecodeQFRCRegisterClass(MCInst &Inst, uint64_t RegNo,
308                                             uint64_t Address,
309                                             const void *Decoder) {
310   return decodeRegisterClass(Inst, RegNo, QFRegs);
311 }
312 
313 #define DecodeQSRCRegisterClass DecodeQFRCRegisterClass
314 #define DecodeQBRCRegisterClass DecodeQFRCRegisterClass
315 
316 template<unsigned N>
317 static DecodeStatus decodeUImmOperand(MCInst &Inst, uint64_t Imm,
318                                       int64_t Address, const void *Decoder) {
319   assert(isUInt<N>(Imm) && "Invalid immediate");
320   Inst.addOperand(MCOperand::createImm(Imm));
321   return MCDisassembler::Success;
322 }
323 
324 template<unsigned N>
325 static DecodeStatus decodeSImmOperand(MCInst &Inst, uint64_t Imm,
326                                       int64_t Address, const void *Decoder) {
327   assert(isUInt<N>(Imm) && "Invalid immediate");
328   Inst.addOperand(MCOperand::createImm(SignExtend64<N>(Imm)));
329   return MCDisassembler::Success;
330 }
331 
332 static DecodeStatus decodeMemRIOperands(MCInst &Inst, uint64_t Imm,
333                                         int64_t Address, const void *Decoder) {
334   // Decode the memri field (imm, reg), which has the low 16-bits as the
335   // displacement and the next 5 bits as the register #.
336 
337   uint64_t Base = Imm >> 16;
338   uint64_t Disp = Imm & 0xFFFF;
339 
340   assert(Base < 32 && "Invalid base register");
341 
342   switch (Inst.getOpcode()) {
343   default: break;
344   case PPC::LBZU:
345   case PPC::LHAU:
346   case PPC::LHZU:
347   case PPC::LWZU:
348   case PPC::LFSU:
349   case PPC::LFDU:
350     // Add the tied output operand.
351     Inst.addOperand(MCOperand::createReg(GP0Regs[Base]));
352     break;
353   case PPC::STBU:
354   case PPC::STHU:
355   case PPC::STWU:
356   case PPC::STFSU:
357   case PPC::STFDU:
358     Inst.insert(Inst.begin(), MCOperand::createReg(GP0Regs[Base]));
359     break;
360   }
361 
362   Inst.addOperand(MCOperand::createImm(SignExtend64<16>(Disp)));
363   Inst.addOperand(MCOperand::createReg(GP0Regs[Base]));
364   return MCDisassembler::Success;
365 }
366 
367 static DecodeStatus decodeMemRIXOperands(MCInst &Inst, uint64_t Imm,
368                                          int64_t Address, const void *Decoder) {
369   // Decode the memrix field (imm, reg), which has the low 14-bits as the
370   // displacement and the next 5 bits as the register #.
371 
372   uint64_t Base = Imm >> 14;
373   uint64_t Disp = Imm & 0x3FFF;
374 
375   assert(Base < 32 && "Invalid base register");
376 
377   if (Inst.getOpcode() == PPC::LDU)
378     // Add the tied output operand.
379     Inst.addOperand(MCOperand::createReg(GP0Regs[Base]));
380   else if (Inst.getOpcode() == PPC::STDU)
381     Inst.insert(Inst.begin(), MCOperand::createReg(GP0Regs[Base]));
382 
383   Inst.addOperand(MCOperand::createImm(SignExtend64<16>(Disp << 2)));
384   Inst.addOperand(MCOperand::createReg(GP0Regs[Base]));
385   return MCDisassembler::Success;
386 }
387 
388 static DecodeStatus decodeMemRIX16Operands(MCInst &Inst, uint64_t Imm,
389                                          int64_t Address, const void *Decoder) {
390   // Decode the memrix16 field (imm, reg), which has the low 12-bits as the
391   // displacement with 16-byte aligned, and the next 5 bits as the register #.
392 
393   uint64_t Base = Imm >> 12;
394   uint64_t Disp = Imm & 0xFFF;
395 
396   assert(Base < 32 && "Invalid base register");
397 
398   Inst.addOperand(MCOperand::createImm(SignExtend64<16>(Disp << 4)));
399   Inst.addOperand(MCOperand::createReg(GP0Regs[Base]));
400   return MCDisassembler::Success;
401 }
402 
403 static DecodeStatus decodeCRBitMOperand(MCInst &Inst, uint64_t Imm,
404                                         int64_t Address, const void *Decoder) {
405   // The cr bit encoding is 0x80 >> cr_reg_num.
406 
407   unsigned Zeros = countTrailingZeros(Imm);
408   assert(Zeros < 8 && "Invalid CR bit value");
409 
410   Inst.addOperand(MCOperand::createReg(CRRegs[7 - Zeros]));
411   return MCDisassembler::Success;
412 }
413 
414 #include "PPCGenDisassemblerTables.inc"
415 
416 DecodeStatus PPCDisassembler::getInstruction(MCInst &MI, uint64_t &Size,
417                                              ArrayRef<uint8_t> Bytes,
418                                              uint64_t Address, raw_ostream &OS,
419                                              raw_ostream &CS) const {
420   // Get the four bytes of the instruction.
421   Size = 4;
422   if (Bytes.size() < 4) {
423     Size = 0;
424     return MCDisassembler::Fail;
425   }
426 
427   // Read the instruction in the proper endianness.
428   uint32_t Inst = IsLittleEndian ? support::endian::read32le(Bytes.data())
429                                  : support::endian::read32be(Bytes.data());
430 
431   if (STI.getFeatureBits()[PPC::FeatureQPX]) {
432     DecodeStatus result =
433       decodeInstruction(DecoderTableQPX32, MI, Inst, Address, this, STI);
434     if (result != MCDisassembler::Fail)
435       return result;
436   }
437 
438   return decodeInstruction(DecoderTable32, MI, Inst, Address, this, STI);
439 }
440 
441