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 /* Capstone Disassembly Engine */
11 /* By Nguyen Anh Quynh <aquynh@gmail.com>, 2013-2015 */
12 
13 #ifdef CAPSTONE_HAS_POWERPC
14 
15 #include <stdio.h>	// DEBUG
16 #include <stdlib.h>
17 #include <string.h>
18 
19 #include "../../cs_priv.h"
20 #include "../../utils.h"
21 
22 #include "PPCDisassembler.h"
23 
24 #include "../../MCInst.h"
25 #include "../../MCInstrDesc.h"
26 #include "../../MCFixedLenDisassembler.h"
27 #include "../../MCRegisterInfo.h"
28 #include "../../MCDisassembler.h"
29 #include "../../MathExtras.h"
30 
31 #define GET_REGINFO_ENUM
32 #include "PPCGenRegisterInfo.inc"
33 
34 
35 // FIXME: These can be generated by TableGen from the existing register
36 // encoding values!
37 
38 static const unsigned CRRegs[] = {
39 	PPC_CR0, PPC_CR1, PPC_CR2, PPC_CR3,
40 	PPC_CR4, PPC_CR5, PPC_CR6, PPC_CR7
41 };
42 
43 static const unsigned CRBITRegs[] = {
44 	PPC_CR0LT, PPC_CR0GT, PPC_CR0EQ, PPC_CR0UN,
45 	PPC_CR1LT, PPC_CR1GT, PPC_CR1EQ, PPC_CR1UN,
46 	PPC_CR2LT, PPC_CR2GT, PPC_CR2EQ, PPC_CR2UN,
47 	PPC_CR3LT, PPC_CR3GT, PPC_CR3EQ, PPC_CR3UN,
48 	PPC_CR4LT, PPC_CR4GT, PPC_CR4EQ, PPC_CR4UN,
49 	PPC_CR5LT, PPC_CR5GT, PPC_CR5EQ, PPC_CR5UN,
50 	PPC_CR6LT, PPC_CR6GT, PPC_CR6EQ, PPC_CR6UN,
51 	PPC_CR7LT, PPC_CR7GT, PPC_CR7EQ, PPC_CR7UN
52 };
53 
54 static const unsigned FRegs[] = {
55 	PPC_F0, PPC_F1, PPC_F2, PPC_F3,
56 	PPC_F4, PPC_F5, PPC_F6, PPC_F7,
57 	PPC_F8, PPC_F9, PPC_F10, PPC_F11,
58 	PPC_F12, PPC_F13, PPC_F14, PPC_F15,
59 	PPC_F16, PPC_F17, PPC_F18, PPC_F19,
60 	PPC_F20, PPC_F21, PPC_F22, PPC_F23,
61 	PPC_F24, PPC_F25, PPC_F26, PPC_F27,
62 	PPC_F28, PPC_F29, PPC_F30, PPC_F31
63 };
64 
65 static const unsigned VRegs[] = {
66 	PPC_V0, PPC_V1, PPC_V2, PPC_V3,
67 	PPC_V4, PPC_V5, PPC_V6, PPC_V7,
68 	PPC_V8, PPC_V9, PPC_V10, PPC_V11,
69 	PPC_V12, PPC_V13, PPC_V14, PPC_V15,
70 	PPC_V16, PPC_V17, PPC_V18, PPC_V19,
71 	PPC_V20, PPC_V21, PPC_V22, PPC_V23,
72 	PPC_V24, PPC_V25, PPC_V26, PPC_V27,
73 	PPC_V28, PPC_V29, PPC_V30, PPC_V31
74 };
75 
76 static const unsigned VSRegs[] = {
77 	PPC_VSL0, PPC_VSL1, PPC_VSL2, PPC_VSL3,
78 	PPC_VSL4, PPC_VSL5, PPC_VSL6, PPC_VSL7,
79 	PPC_VSL8, PPC_VSL9, PPC_VSL10, PPC_VSL11,
80 	PPC_VSL12, PPC_VSL13, PPC_VSL14, PPC_VSL15,
81 	PPC_VSL16, PPC_VSL17, PPC_VSL18, PPC_VSL19,
82 	PPC_VSL20, PPC_VSL21, PPC_VSL22, PPC_VSL23,
83 	PPC_VSL24, PPC_VSL25, PPC_VSL26, PPC_VSL27,
84 	PPC_VSL28, PPC_VSL29, PPC_VSL30, PPC_VSL31,
85 
86 	PPC_VSH0, PPC_VSH1, PPC_VSH2, PPC_VSH3,
87 	PPC_VSH4, PPC_VSH5, PPC_VSH6, PPC_VSH7,
88 	PPC_VSH8, PPC_VSH9, PPC_VSH10, PPC_VSH11,
89 	PPC_VSH12, PPC_VSH13, PPC_VSH14, PPC_VSH15,
90 	PPC_VSH16, PPC_VSH17, PPC_VSH18, PPC_VSH19,
91 	PPC_VSH20, PPC_VSH21, PPC_VSH22, PPC_VSH23,
92 	PPC_VSH24, PPC_VSH25, PPC_VSH26, PPC_VSH27,
93 	PPC_VSH28, PPC_VSH29, PPC_VSH30, PPC_VSH31
94 };
95 
96 static const unsigned VSFRegs[] = {
97 	PPC_F0, PPC_F1, PPC_F2, PPC_F3,
98 	PPC_F4, PPC_F5, PPC_F6, PPC_F7,
99 	PPC_F8, PPC_F9, PPC_F10, PPC_F11,
100 	PPC_F12, PPC_F13, PPC_F14, PPC_F15,
101 	PPC_F16, PPC_F17, PPC_F18, PPC_F19,
102 	PPC_F20, PPC_F21, PPC_F22, PPC_F23,
103 	PPC_F24, PPC_F25, PPC_F26, PPC_F27,
104 	PPC_F28, PPC_F29, PPC_F30, PPC_F31,
105 
106 	PPC_VF0, PPC_VF1, PPC_VF2, PPC_VF3,
107 	PPC_VF4, PPC_VF5, PPC_VF6, PPC_VF7,
108 	PPC_VF8, PPC_VF9, PPC_VF10, PPC_VF11,
109 	PPC_VF12, PPC_VF13, PPC_VF14, PPC_VF15,
110 	PPC_VF16, PPC_VF17, PPC_VF18, PPC_VF19,
111 	PPC_VF20, PPC_VF21, PPC_VF22, PPC_VF23,
112 	PPC_VF24, PPC_VF25, PPC_VF26, PPC_VF27,
113 	PPC_VF28, PPC_VF29, PPC_VF30, PPC_VF31
114 };
115 
116 static const unsigned GPRegs[] = {
117 	PPC_R0, PPC_R1, PPC_R2, PPC_R3,
118 	PPC_R4, PPC_R5, PPC_R6, PPC_R7,
119 	PPC_R8, PPC_R9, PPC_R10, PPC_R11,
120 	PPC_R12, PPC_R13, PPC_R14, PPC_R15,
121 	PPC_R16, PPC_R17, PPC_R18, PPC_R19,
122 	PPC_R20, PPC_R21, PPC_R22, PPC_R23,
123 	PPC_R24, PPC_R25, PPC_R26, PPC_R27,
124 	PPC_R28, PPC_R29, PPC_R30, PPC_R31
125 };
126 
127 static const unsigned GP0Regs[] = {
128 	PPC_ZERO, PPC_R1, PPC_R2, PPC_R3,
129 	PPC_R4, PPC_R5, PPC_R6, PPC_R7,
130 	PPC_R8, PPC_R9, PPC_R10, PPC_R11,
131 	PPC_R12, PPC_R13, PPC_R14, PPC_R15,
132 	PPC_R16, PPC_R17, PPC_R18, PPC_R19,
133 	PPC_R20, PPC_R21, PPC_R22, PPC_R23,
134 	PPC_R24, PPC_R25, PPC_R26, PPC_R27,
135 	PPC_R28, PPC_R29, PPC_R30, PPC_R31
136 };
137 
138 static const unsigned G8Regs[] = {
139 	PPC_X0, PPC_X1, PPC_X2, PPC_X3,
140 	PPC_X4, PPC_X5, PPC_X6, PPC_X7,
141 	PPC_X8, PPC_X9, PPC_X10, PPC_X11,
142 	PPC_X12, PPC_X13, PPC_X14, PPC_X15,
143 	PPC_X16, PPC_X17, PPC_X18, PPC_X19,
144 	PPC_X20, PPC_X21, PPC_X22, PPC_X23,
145 	PPC_X24, PPC_X25, PPC_X26, PPC_X27,
146 	PPC_X28, PPC_X29, PPC_X30, PPC_X31
147 };
148 
149 static const unsigned QFRegs[] = {
150 	PPC_QF0, PPC_QF1, PPC_QF2, PPC_QF3,
151 	PPC_QF4, PPC_QF5, PPC_QF6, PPC_QF7,
152 	PPC_QF8, PPC_QF9, PPC_QF10, PPC_QF11,
153 	PPC_QF12, PPC_QF13, PPC_QF14, PPC_QF15,
154 	PPC_QF16, PPC_QF17, PPC_QF18, PPC_QF19,
155 	PPC_QF20, PPC_QF21, PPC_QF22, PPC_QF23,
156 	PPC_QF24, PPC_QF25, PPC_QF26, PPC_QF27,
157 	PPC_QF28, PPC_QF29, PPC_QF30, PPC_QF31
158 };
159 
getFeatureBits(int feature)160 static uint64_t getFeatureBits(int feature)
161 {
162 	// enable all features
163 	return (uint64_t)-1;
164 }
165 
decodeRegisterClass(MCInst * Inst,uint64_t RegNo,const unsigned * Regs)166 static DecodeStatus decodeRegisterClass(MCInst *Inst, uint64_t RegNo,
167 		const unsigned *Regs)
168 {
169 	// assert(RegNo < N && "Invalid register number");
170 	MCOperand_CreateReg0(Inst, Regs[RegNo]);
171 	return MCDisassembler_Success;
172 }
173 
DecodeCRRCRegisterClass(MCInst * Inst,uint64_t RegNo,uint64_t Address,const void * Decoder)174 static DecodeStatus DecodeCRRCRegisterClass(MCInst *Inst, uint64_t RegNo,
175 		uint64_t Address,
176 		const void *Decoder)
177 {
178 	return decodeRegisterClass(Inst, RegNo, CRRegs);
179 }
180 
DecodeCRBITRCRegisterClass(MCInst * Inst,uint64_t RegNo,uint64_t Address,const void * Decoder)181 static DecodeStatus DecodeCRBITRCRegisterClass(MCInst *Inst, uint64_t RegNo,
182 		uint64_t Address,
183 		const void *Decoder)
184 {
185 	return decodeRegisterClass(Inst, RegNo, CRBITRegs);
186 }
187 
DecodeF4RCRegisterClass(MCInst * Inst,uint64_t RegNo,uint64_t Address,const void * Decoder)188 static DecodeStatus DecodeF4RCRegisterClass(MCInst *Inst, uint64_t RegNo,
189 		uint64_t Address,
190 		const void *Decoder)
191 {
192 	return decodeRegisterClass(Inst, RegNo, FRegs);
193 }
194 
DecodeF8RCRegisterClass(MCInst * Inst,uint64_t RegNo,uint64_t Address,const void * Decoder)195 static DecodeStatus DecodeF8RCRegisterClass(MCInst *Inst, uint64_t RegNo,
196 		uint64_t Address,
197 		const void *Decoder)
198 {
199 	return decodeRegisterClass(Inst, RegNo, FRegs);
200 }
201 
DecodeVRRCRegisterClass(MCInst * Inst,uint64_t RegNo,uint64_t Address,const void * Decoder)202 static DecodeStatus DecodeVRRCRegisterClass(MCInst *Inst, uint64_t RegNo,
203 		uint64_t Address,
204 		const void *Decoder)
205 {
206 	return decodeRegisterClass(Inst, RegNo, VRegs);
207 }
208 
DecodeVSRCRegisterClass(MCInst * Inst,uint64_t RegNo,uint64_t Address,const void * Decoder)209 static DecodeStatus DecodeVSRCRegisterClass(MCInst *Inst, uint64_t RegNo,
210 		uint64_t Address,
211 		const void *Decoder)
212 {
213 	return decodeRegisterClass(Inst, RegNo, VSRegs);
214 }
215 
DecodeVSFRCRegisterClass(MCInst * Inst,uint64_t RegNo,uint64_t Address,const void * Decoder)216 static DecodeStatus DecodeVSFRCRegisterClass(MCInst *Inst, uint64_t RegNo,
217 		uint64_t Address,
218 		const void *Decoder)
219 {
220 	return decodeRegisterClass(Inst, RegNo, VSFRegs);
221 }
222 
DecodeGPRCRegisterClass(MCInst * Inst,uint64_t RegNo,uint64_t Address,const void * Decoder)223 static DecodeStatus DecodeGPRCRegisterClass(MCInst *Inst, uint64_t RegNo,
224 		uint64_t Address,
225 		const void *Decoder)
226 {
227 	return decodeRegisterClass(Inst, RegNo, GPRegs);
228 }
229 
DecodeGPRC_NOR0RegisterClass(MCInst * Inst,uint64_t RegNo,uint64_t Address,const void * Decoder)230 static DecodeStatus DecodeGPRC_NOR0RegisterClass(MCInst *Inst, uint64_t RegNo,
231 		uint64_t Address,
232 		const void *Decoder)
233 {
234 	return decodeRegisterClass(Inst, RegNo, GP0Regs);
235 }
236 
DecodeG8RCRegisterClass(MCInst * Inst,uint64_t RegNo,uint64_t Address,const void * Decoder)237 static DecodeStatus DecodeG8RCRegisterClass(MCInst *Inst, uint64_t RegNo,
238 		uint64_t Address,
239 		const void *Decoder)
240 {
241 	return decodeRegisterClass(Inst, RegNo, G8Regs);
242 }
243 
244 #define DecodePointerLikeRegClass0 DecodeGPRCRegisterClass
245 #define DecodePointerLikeRegClass1 DecodeGPRC_NOR0RegisterClass
246 
DecodeQFRCRegisterClass(MCInst * Inst,uint64_t RegNo,uint64_t Address,const void * Decoder)247 static DecodeStatus DecodeQFRCRegisterClass(MCInst *Inst, uint64_t RegNo,
248 		uint64_t Address,
249 		const void *Decoder)
250 {
251 	return decodeRegisterClass(Inst, RegNo, QFRegs);
252 }
253 
254 #define DecodeQSRCRegisterClass DecodeQFRCRegisterClass
255 #define DecodeQBRCRegisterClass DecodeQFRCRegisterClass
256 
decodeUImmOperand(MCInst * Inst,uint64_t Imm,int64_t Address,const void * Decoder,unsigned N)257 static DecodeStatus decodeUImmOperand(MCInst *Inst, uint64_t Imm,
258 		int64_t Address, const void *Decoder, unsigned N)
259 {
260 	//assert(isUInt<N>(Imm) && "Invalid immediate");
261 	MCOperand_CreateImm0(Inst, Imm);
262 	return MCDisassembler_Success;
263 }
264 
decodeSImmOperand(MCInst * Inst,uint64_t Imm,int64_t Address,const void * Decoder,unsigned N)265 static DecodeStatus decodeSImmOperand(MCInst *Inst, uint64_t Imm,
266 		int64_t Address, const void *Decoder, unsigned N)
267 {
268 	// assert(isUInt<N>(Imm) && "Invalid immediate");
269 	MCOperand_CreateImm0(Inst, SignExtend64(Imm, N));
270 	return MCDisassembler_Success;
271 }
272 
273 
274 #define GET_INSTRINFO_ENUM
275 #include "PPCGenInstrInfo.inc"
276 
decodeMemRIOperands(MCInst * Inst,uint64_t Imm,int64_t Address,const void * Decoder)277 static DecodeStatus decodeMemRIOperands(MCInst *Inst, uint64_t Imm,
278 		int64_t Address, const void *Decoder)
279 {
280 	// Decode the memri field (imm, reg), which has the low 16-bits as the
281 	// displacement and the next 5 bits as the register #.
282 
283 	uint64_t Base = Imm >> 16;
284 	uint64_t Disp = Imm & 0xFFFF;
285 
286 	// assert(Base < 32 && "Invalid base register");
287 	if (Base >= 32)
288 		return MCDisassembler_Fail;
289 
290 	switch (MCInst_getOpcode(Inst)) {
291 		default: break;
292 		case PPC_LBZU:
293 		case PPC_LHAU:
294 		case PPC_LHZU:
295 		case PPC_LWZU:
296 		case PPC_LFSU:
297 		case PPC_LFDU:
298 				 // Add the tied output operand.
299 				 MCOperand_CreateReg0(Inst, GP0Regs[Base]);
300 				 break;
301 		case PPC_STBU:
302 		case PPC_STHU:
303 		case PPC_STWU:
304 		case PPC_STFSU:
305 		case PPC_STFDU:
306 				 MCInst_insert0(Inst, 0, MCOperand_CreateReg1(Inst, GP0Regs[Base]));
307 				 break;
308 	}
309 
310 	MCOperand_CreateImm0(Inst, SignExtend64(Disp, 16));
311 	MCOperand_CreateReg0(Inst, GP0Regs[Base]);
312 	return MCDisassembler_Success;
313 }
314 
decodeMemRIXOperands(MCInst * Inst,uint64_t Imm,int64_t Address,const void * Decoder)315 static DecodeStatus decodeMemRIXOperands(MCInst *Inst, uint64_t Imm,
316 		int64_t Address, const void *Decoder)
317 {
318 	// Decode the memrix field (imm, reg), which has the low 14-bits as the
319 	// displacement and the next 5 bits as the register #.
320 
321 	uint64_t Base = Imm >> 14;
322 	uint64_t Disp = Imm & 0x3FFF;
323 
324 	// assert(Base < 32 && "Invalid base register");
325 
326 	if (MCInst_getOpcode(Inst) == PPC_LDU)
327 		// Add the tied output operand.
328 		MCOperand_CreateReg0(Inst, GP0Regs[Base]);
329 	else if (MCInst_getOpcode(Inst) == PPC_STDU)
330 		MCInst_insert0(Inst, 0, MCOperand_CreateReg1(Inst, GP0Regs[Base]));
331 
332 	MCOperand_CreateImm0(Inst, SignExtend64(Disp << 2, 16));
333 	MCOperand_CreateReg0(Inst, GP0Regs[Base]);
334 	return MCDisassembler_Success;
335 }
336 
decodeCRBitMOperand(MCInst * Inst,uint64_t Imm,int64_t Address,const void * Decoder)337 static DecodeStatus decodeCRBitMOperand(MCInst *Inst, uint64_t Imm,
338 		int64_t Address, const void *Decoder)
339 {
340 	// The cr bit encoding is 0x80 >> cr_reg_num.
341 
342 	unsigned Zeros = CountTrailingZeros_64(Imm);
343 	// assert(Zeros < 8 && "Invalid CR bit value");
344 	if (Zeros >=8)
345 		return MCDisassembler_Fail;
346 
347 	MCOperand_CreateReg0(Inst, CRRegs[7 - Zeros]);
348 	return MCDisassembler_Success;
349 }
350 
351 #include "PPCGenDisassemblerTables.inc"
352 
getInstruction(MCInst * MI,const uint8_t * code,size_t code_len,uint16_t * Size,uint64_t Address,MCRegisterInfo * MRI)353 static DecodeStatus getInstruction(MCInst *MI,
354 		const uint8_t *code, size_t code_len,
355 		uint16_t *Size,
356 		uint64_t Address, MCRegisterInfo *MRI)
357 {
358 	uint32_t insn;
359 	DecodeStatus result;
360 	// Get the four bytes of the instruction.
361 	if (code_len < 4) {
362 		// not enough data
363 		*Size = 0;
364 		return MCDisassembler_Fail;
365 	}
366 
367 	// The instruction is big-endian encoded.
368 	if (MODE_IS_BIG_ENDIAN(MI->csh->mode))
369 		insn = ((uint32_t) code[0] << 24) | (code[1] << 16) |
370 			(code[2] <<  8) | (code[3] <<  0);
371 	else
372 		insn = ((uint32_t) code[3] << 24) | (code[2] << 16) |
373 			(code[1] <<  8) | (code[0] <<  0);
374 
375 	if (MI->flat_insn->detail) {
376 		memset(MI->flat_insn->detail, 0, offsetof(cs_detail, ppc)+sizeof(cs_ppc));
377 	}
378 
379 	if (MI->csh->mode & CS_MODE_QPX) {
380 		result = decodeInstruction_4(DecoderTableQPX32, MI, insn, Address, 4);
381 		if (result != MCDisassembler_Fail) {
382 			*Size = 4;
383 			return result;
384 		}
385 
386 		MCInst_clear(MI);
387 	}
388 
389 	result = decodeInstruction_4(DecoderTable32, MI, insn, Address, 4);
390 	if (result != MCDisassembler_Fail) {
391 		*Size = 4;
392 		return result;
393 	}
394 
395 	// report error
396 	MCInst_clear(MI);
397 	*Size = 0;
398 	return MCDisassembler_Fail;
399 }
400 
PPC_getInstruction(csh ud,const uint8_t * code,size_t code_len,MCInst * instr,uint16_t * size,uint64_t address,void * info)401 bool PPC_getInstruction(csh ud, const uint8_t *code, size_t code_len,
402 		MCInst *instr, uint16_t *size, uint64_t address, void *info)
403 {
404 	DecodeStatus status = getInstruction(instr,
405 			code, code_len,
406 			size,
407 			address, (MCRegisterInfo *)info);
408 
409 	return status == MCDisassembler_Success;
410 }
411 
412 #define GET_REGINFO_MC_DESC
413 #include "PPCGenRegisterInfo.inc"
PPC_init(MCRegisterInfo * MRI)414 void PPC_init(MCRegisterInfo *MRI)
415 {
416 	/*
417 	   InitMCRegisterInfo(PPCRegDesc, 310, RA, PC,
418 	   PPCMCRegisterClasses, 23,
419 	   PPCRegUnitRoots,
420 	   138,
421 	   PPCRegDiffLists,
422 	   PPCLaneMaskLists,
423 	   PPCRegStrings,
424 	   PPCRegClassStrings,
425 	   PPCSubRegIdxLists,
426 	   8,
427 	   PPCSubRegIdxRanges,
428 	   PPCRegEncodingTable);
429 	 */
430 
431 
432 	MCRegisterInfo_InitMCRegisterInfo(MRI, PPCRegDesc, 310,
433 			0, 0,
434 			PPCMCRegisterClasses, 23,
435 			0, 0,
436 			PPCRegDiffLists,
437 			0,
438 			PPCSubRegIdxLists, 8,
439 			0);
440 }
441 
442 #endif
443