xref: /llvm-project/llvm/lib/Target/PowerPC/Disassembler/PPCDisassembler.cpp (revision 22e7da9597a267165ee03cbabd31c1e4c13c5cb9)
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(getThePPC32Target(),
55                                          createPPCDisassembler);
56   TargetRegistry::RegisterMCDisassembler(getThePPC64Target(),
57                                          createPPCDisassembler);
58   TargetRegistry::RegisterMCDisassembler(getThePPC64LETarget(),
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 G80Regs[] = {
208   PPC::ZERO8, PPC::X1, PPC::X2, PPC::X3,
209   PPC::X4, PPC::X5, PPC::X6, PPC::X7,
210   PPC::X8, PPC::X9, PPC::X10, PPC::X11,
211   PPC::X12, PPC::X13, PPC::X14, PPC::X15,
212   PPC::X16, PPC::X17, PPC::X18, PPC::X19,
213   PPC::X20, PPC::X21, PPC::X22, PPC::X23,
214   PPC::X24, PPC::X25, PPC::X26, PPC::X27,
215   PPC::X28, PPC::X29, PPC::X30, PPC::X31
216 };
217 
218 static const unsigned QFRegs[] = {
219   PPC::QF0, PPC::QF1, PPC::QF2, PPC::QF3,
220   PPC::QF4, PPC::QF5, PPC::QF6, PPC::QF7,
221   PPC::QF8, PPC::QF9, PPC::QF10, PPC::QF11,
222   PPC::QF12, PPC::QF13, PPC::QF14, PPC::QF15,
223   PPC::QF16, PPC::QF17, PPC::QF18, PPC::QF19,
224   PPC::QF20, PPC::QF21, PPC::QF22, PPC::QF23,
225   PPC::QF24, PPC::QF25, PPC::QF26, PPC::QF27,
226   PPC::QF28, PPC::QF29, PPC::QF30, PPC::QF31
227 };
228 
229 template <std::size_t N>
230 static DecodeStatus decodeRegisterClass(MCInst &Inst, uint64_t RegNo,
231                                         const unsigned (&Regs)[N]) {
232   assert(RegNo < N && "Invalid register number");
233   Inst.addOperand(MCOperand::createReg(Regs[RegNo]));
234   return MCDisassembler::Success;
235 }
236 
237 static DecodeStatus DecodeCRRCRegisterClass(MCInst &Inst, uint64_t RegNo,
238                                             uint64_t Address,
239                                             const void *Decoder) {
240   return decodeRegisterClass(Inst, RegNo, CRRegs);
241 }
242 
243 static DecodeStatus DecodeCRRC0RegisterClass(MCInst &Inst, uint64_t RegNo,
244                                             uint64_t Address,
245                                             const void *Decoder) {
246   return decodeRegisterClass(Inst, RegNo, CRRegs);
247 }
248 
249 static DecodeStatus DecodeCRBITRCRegisterClass(MCInst &Inst, uint64_t RegNo,
250                                             uint64_t Address,
251                                             const void *Decoder) {
252   return decodeRegisterClass(Inst, RegNo, CRBITRegs);
253 }
254 
255 static DecodeStatus DecodeF4RCRegisterClass(MCInst &Inst, uint64_t RegNo,
256                                             uint64_t Address,
257                                             const void *Decoder) {
258   return decodeRegisterClass(Inst, RegNo, FRegs);
259 }
260 
261 static DecodeStatus DecodeF8RCRegisterClass(MCInst &Inst, uint64_t RegNo,
262                                             uint64_t Address,
263                                             const void *Decoder) {
264   return decodeRegisterClass(Inst, RegNo, FRegs);
265 }
266 
267 static DecodeStatus DecodeVFRCRegisterClass(MCInst &Inst, uint64_t RegNo,
268                                             uint64_t Address,
269                                             const void *Decoder) {
270   return decodeRegisterClass(Inst, RegNo, VFRegs);
271 }
272 
273 static DecodeStatus DecodeVRRCRegisterClass(MCInst &Inst, uint64_t RegNo,
274                                             uint64_t Address,
275                                             const void *Decoder) {
276   return decodeRegisterClass(Inst, RegNo, VRegs);
277 }
278 
279 static DecodeStatus DecodeVSRCRegisterClass(MCInst &Inst, uint64_t RegNo,
280                                             uint64_t Address,
281                                             const void *Decoder) {
282   return decodeRegisterClass(Inst, RegNo, VSRegs);
283 }
284 
285 static DecodeStatus DecodeVSFRCRegisterClass(MCInst &Inst, uint64_t RegNo,
286                                             uint64_t Address,
287                                             const void *Decoder) {
288   return decodeRegisterClass(Inst, RegNo, VSFRegs);
289 }
290 
291 static DecodeStatus DecodeVSSRCRegisterClass(MCInst &Inst, uint64_t RegNo,
292                                             uint64_t Address,
293                                             const void *Decoder) {
294   return decodeRegisterClass(Inst, RegNo, VSSRegs);
295 }
296 
297 static DecodeStatus DecodeGPRCRegisterClass(MCInst &Inst, uint64_t RegNo,
298                                             uint64_t Address,
299                                             const void *Decoder) {
300   return decodeRegisterClass(Inst, RegNo, GPRegs);
301 }
302 
303 static DecodeStatus DecodeGPRC_NOR0RegisterClass(MCInst &Inst, uint64_t RegNo,
304                                             uint64_t Address,
305                                             const void *Decoder) {
306   return decodeRegisterClass(Inst, RegNo, GP0Regs);
307 }
308 
309 static DecodeStatus DecodeG8RCRegisterClass(MCInst &Inst, uint64_t RegNo,
310                                             uint64_t Address,
311                                             const void *Decoder) {
312   return decodeRegisterClass(Inst, RegNo, G8Regs);
313 }
314 
315 static DecodeStatus DecodeG8RC_NOX0RegisterClass(MCInst &Inst, uint64_t RegNo,
316                                             uint64_t Address,
317                                             const void *Decoder) {
318   return decodeRegisterClass(Inst, RegNo, G80Regs);
319 }
320 
321 #define DecodePointerLikeRegClass0 DecodeGPRCRegisterClass
322 #define DecodePointerLikeRegClass1 DecodeGPRC_NOR0RegisterClass
323 
324 static DecodeStatus DecodeQFRCRegisterClass(MCInst &Inst, uint64_t RegNo,
325                                             uint64_t Address,
326                                             const void *Decoder) {
327   return decodeRegisterClass(Inst, RegNo, QFRegs);
328 }
329 
330 #define DecodeQSRCRegisterClass DecodeQFRCRegisterClass
331 #define DecodeQBRCRegisterClass DecodeQFRCRegisterClass
332 
333 template<unsigned N>
334 static DecodeStatus decodeUImmOperand(MCInst &Inst, uint64_t Imm,
335                                       int64_t Address, const void *Decoder) {
336   assert(isUInt<N>(Imm) && "Invalid immediate");
337   Inst.addOperand(MCOperand::createImm(Imm));
338   return MCDisassembler::Success;
339 }
340 
341 template<unsigned N>
342 static DecodeStatus decodeSImmOperand(MCInst &Inst, uint64_t Imm,
343                                       int64_t Address, const void *Decoder) {
344   assert(isUInt<N>(Imm) && "Invalid immediate");
345   Inst.addOperand(MCOperand::createImm(SignExtend64<N>(Imm)));
346   return MCDisassembler::Success;
347 }
348 
349 static DecodeStatus decodeMemRIOperands(MCInst &Inst, uint64_t Imm,
350                                         int64_t Address, const void *Decoder) {
351   // Decode the memri field (imm, reg), which has the low 16-bits as the
352   // displacement and the next 5 bits as the register #.
353 
354   uint64_t Base = Imm >> 16;
355   uint64_t Disp = Imm & 0xFFFF;
356 
357   assert(Base < 32 && "Invalid base register");
358 
359   switch (Inst.getOpcode()) {
360   default: break;
361   case PPC::LBZU:
362   case PPC::LHAU:
363   case PPC::LHZU:
364   case PPC::LWZU:
365   case PPC::LFSU:
366   case PPC::LFDU:
367     // Add the tied output operand.
368     Inst.addOperand(MCOperand::createReg(GP0Regs[Base]));
369     break;
370   case PPC::STBU:
371   case PPC::STHU:
372   case PPC::STWU:
373   case PPC::STFSU:
374   case PPC::STFDU:
375     Inst.insert(Inst.begin(), MCOperand::createReg(GP0Regs[Base]));
376     break;
377   }
378 
379   Inst.addOperand(MCOperand::createImm(SignExtend64<16>(Disp)));
380   Inst.addOperand(MCOperand::createReg(GP0Regs[Base]));
381   return MCDisassembler::Success;
382 }
383 
384 static DecodeStatus decodeMemRIXOperands(MCInst &Inst, uint64_t Imm,
385                                          int64_t Address, const void *Decoder) {
386   // Decode the memrix field (imm, reg), which has the low 14-bits as the
387   // displacement and the next 5 bits as the register #.
388 
389   uint64_t Base = Imm >> 14;
390   uint64_t Disp = Imm & 0x3FFF;
391 
392   assert(Base < 32 && "Invalid base register");
393 
394   if (Inst.getOpcode() == PPC::LDU)
395     // Add the tied output operand.
396     Inst.addOperand(MCOperand::createReg(GP0Regs[Base]));
397   else if (Inst.getOpcode() == PPC::STDU)
398     Inst.insert(Inst.begin(), MCOperand::createReg(GP0Regs[Base]));
399 
400   Inst.addOperand(MCOperand::createImm(SignExtend64<16>(Disp << 2)));
401   Inst.addOperand(MCOperand::createReg(GP0Regs[Base]));
402   return MCDisassembler::Success;
403 }
404 
405 static DecodeStatus decodeMemRIX16Operands(MCInst &Inst, uint64_t Imm,
406                                          int64_t Address, const void *Decoder) {
407   // Decode the memrix16 field (imm, reg), which has the low 12-bits as the
408   // displacement with 16-byte aligned, and the next 5 bits as the register #.
409 
410   uint64_t Base = Imm >> 12;
411   uint64_t Disp = Imm & 0xFFF;
412 
413   assert(Base < 32 && "Invalid base register");
414 
415   Inst.addOperand(MCOperand::createImm(SignExtend64<16>(Disp << 4)));
416   Inst.addOperand(MCOperand::createReg(GP0Regs[Base]));
417   return MCDisassembler::Success;
418 }
419 
420 static DecodeStatus decodeCRBitMOperand(MCInst &Inst, uint64_t Imm,
421                                         int64_t Address, const void *Decoder) {
422   // The cr bit encoding is 0x80 >> cr_reg_num.
423 
424   unsigned Zeros = countTrailingZeros(Imm);
425   assert(Zeros < 8 && "Invalid CR bit value");
426 
427   Inst.addOperand(MCOperand::createReg(CRRegs[7 - Zeros]));
428   return MCDisassembler::Success;
429 }
430 
431 #include "PPCGenDisassemblerTables.inc"
432 
433 DecodeStatus PPCDisassembler::getInstruction(MCInst &MI, uint64_t &Size,
434                                              ArrayRef<uint8_t> Bytes,
435                                              uint64_t Address, raw_ostream &OS,
436                                              raw_ostream &CS) const {
437   // Get the four bytes of the instruction.
438   Size = 4;
439   if (Bytes.size() < 4) {
440     Size = 0;
441     return MCDisassembler::Fail;
442   }
443 
444   // Read the instruction in the proper endianness.
445   uint32_t Inst = IsLittleEndian ? support::endian::read32le(Bytes.data())
446                                  : support::endian::read32be(Bytes.data());
447 
448   if (STI.getFeatureBits()[PPC::FeatureQPX]) {
449     DecodeStatus result =
450       decodeInstruction(DecoderTableQPX32, MI, Inst, Address, this, STI);
451     if (result != MCDisassembler::Fail)
452       return result;
453   }
454 
455   return decodeInstruction(DecoderTable32, MI, Inst, Address, this, STI);
456 }
457 
458