1 /* 2 * Licensed to the Apache Software Foundation (ASF) under one or more 3 * contributor license agreements. See the NOTICE file distributed with 4 * this work for additional information regarding copyright ownership. 5 * The ASF licenses this file to You under the Apache License, Version 2.0 6 * (the "License"); you may not use this file except in compliance with 7 * the License. You may obtain a copy of the License at 8 * 9 * http://www.apache.org/licenses/LICENSE-2.0 10 * 11 * Unless required by applicable law or agreed to in writing, software 12 * distributed under the License is distributed on an "AS IS" BASIS, 13 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. 14 * See the License for the specific language governing permissions and 15 * limitations under the License. 16 */ 17 /** 18 * @author Alexander V. Astapchuk 19 */ 20 #include "enc_base.h" 21 //#include <climits> 22 #include <string.h> 23 #define USE_ENCODER_DEFINES 24 #include "enc_prvt.h" 25 #include <stdio.h> 26 27 //#define JET_PROTO 28 29 #ifdef JET_PROTO 30 #include "dec_base.h" 31 #include "jvmti_dasm.h" 32 #endif 33 34 ENCODER_NAMESPACE_START 35 36 /** 37 * @file 38 * @brief Main encoding routines and structures. 39 */ 40 41 #ifndef _WIN32 42 #define strcmpi strcasecmp 43 #endif 44 45 int EncoderBase::dummy = EncoderBase::buildTable(); 46 47 const unsigned char EncoderBase::size_hash[OpndSize_64+1] = { 48 // 49 0xFF, // OpndSize_Null = 0, 50 3, // OpndSize_8 = 0x1, 51 2, // OpndSize_16 = 0x2, 52 0xFF, // 0x3 53 1, // OpndSize_32 = 0x4, 54 0xFF, // 0x5 55 0xFF, // 0x6 56 0xFF, // 0x7 57 0, // OpndSize_64 = 0x8, 58 // 59 }; 60 61 const unsigned char EncoderBase::kind_hash[OpndKind_Mem+1] = { 62 // 63 //gp reg -> 000 = 0 64 //memory -> 001 = 1 65 //immediate -> 010 = 2 66 //xmm reg -> 011 = 3 67 //segment regs -> 100 = 4 68 //fp reg -> 101 = 5 69 //mmx reg -> 110 = 6 70 // 71 0xFF, // 0 OpndKind_Null=0, 72 0<<2, // 1 OpndKind_GPReg = 73 // OpndKind_MinRegKind=0x1, 74 4<<2, // 2 OpndKind_SReg=0x2, 75 76 #ifdef _HAVE_MMX_ 77 6<<2, // 3 78 #else 79 0xFF, // 3 80 #endif 81 82 5<<2, // 4 OpndKind_FPReg=0x4, 83 0xFF, 0xFF, 0xFF, // 5, 6, 7 84 3<<2, // OpndKind_XMMReg=0x8, 85 0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF, // 9, 0xA, 0xB, 0xC, 0xD, 86 // 0xE, 0xF 87 0xFF, // OpndKind_MaxRegKind = 88 // OpndKind_StatusReg = 89 // OpndKind_OtherReg=0x10, 90 0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF, // 0x11-0x18 91 0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF, // 0x19-0x1F 92 2<<2, // OpndKind_Immediate=0x20, 93 0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF, // 0x21-0x28 94 0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF, // 0x29-0x30 95 0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF, // 0x31-0x38 96 0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF, // 0x39-0x3F 97 1<<2, // OpndKind_Memory=0x40 98 }; 99 100 char * EncoderBase::curRelOpnd[3]; 101 102 char* EncoderBase::encode_aux(char* stream, unsigned aux, 103 const Operands& opnds, const OpcodeDesc * odesc, 104 unsigned * pargsCount, Rex * prex) 105 { 106 const unsigned byte = aux; 107 OpcodeByteKind kind = (OpcodeByteKind)(byte & OpcodeByteKind_KindMask); 108 // The '>>' here is to force the switch to be table-based) instead of 109 // set of CMP+Jcc. 110 if (*pargsCount >= COUNTOF(opnds)) { 111 assert(false); 112 return stream; 113 } 114 switch(kind>>8) { 115 case OpcodeByteKind_SlashR>>8: 116 // /r - Indicates that the ModR/M byte of the instruction contains 117 // both a register operand and an r/m operand. 118 { 119 assert(opnds.count() > 1); 120 // not true anymore for MOVQ xmm<->r 121 //assert((odesc->opnds[0].kind & OpndKind_Mem) || 122 // (odesc->opnds[1].kind & OpndKind_Mem)); 123 unsigned memidx = odesc->opnds[0].kind & OpndKind_Mem ? 0 : 1; 124 unsigned regidx = memidx == 0 ? 1 : 0; 125 memidx += *pargsCount; 126 regidx += *pargsCount; 127 ModRM& modrm = *(ModRM*)stream; 128 if (memidx >= COUNTOF(opnds) || regidx >= COUNTOF(opnds)) { 129 assert(false); 130 break; 131 } 132 if (opnds[memidx].is_mem()) { 133 stream = encodeModRM(stream, opnds, memidx, odesc, prex); 134 } 135 else { 136 modrm.mod = 3; // 11 137 modrm.rm = getHWRegIndex(opnds[memidx].reg()); 138 #ifdef _EM64T_ 139 if (opnds[memidx].need_rex() && needs_rex_r(opnds[memidx].reg())) { 140 prex->b = 1; 141 } 142 #endif 143 ++stream; 144 } 145 modrm.reg = getHWRegIndex(opnds[regidx].reg()); 146 #ifdef _EM64T_ 147 if (opnds[regidx].need_rex() && needs_rex_r(opnds[regidx].reg())) { 148 prex->r = 1; 149 } 150 #endif 151 *pargsCount += 2; 152 } 153 break; 154 case OpcodeByteKind_SlashNum>>8: 155 // /digit - A digit between 0 and 7 indicates that the 156 // ModR/M byte of the instruction uses only the r/m 157 // (register or memory) operand. The reg field contains 158 // the digit that provides an extension to the instruction's 159 // opcode. 160 { 161 const unsigned lowByte = (byte & OpcodeByteKind_OpcodeMask); 162 assert(lowByte <= 7); 163 ModRM& modrm = *(ModRM*)stream; 164 unsigned idx = *pargsCount; 165 assert(opnds[idx].is_mem() || opnds[idx].is_reg()); 166 if (opnds[idx].is_mem()) { 167 stream = encodeModRM(stream, opnds, idx, odesc, prex); 168 } 169 else { 170 modrm.mod = 3; // 11 171 modrm.rm = getHWRegIndex(opnds[idx].reg()); 172 #ifdef _EM64T_ 173 if (opnds[idx].need_rex() && needs_rex_r(opnds[idx].reg())) { 174 prex->b = 1; 175 } 176 #endif 177 ++stream; 178 } 179 modrm.reg = (char)lowByte; 180 *pargsCount += 1; 181 } 182 break; 183 case OpcodeByteKind_plus_i>>8: 184 // +i - A number used in floating-point instructions when one 185 // of the operands is ST(i) from the FPU register stack. The 186 // number i (which can range from 0 to 7) is added to the 187 // hexadecimal byte given at the left of the plus sign to form 188 // a single opcode byte. 189 { 190 unsigned idx = *pargsCount; 191 const unsigned lowByte = (byte & OpcodeByteKind_OpcodeMask); 192 *stream = (char)lowByte + getHWRegIndex(opnds[idx].reg()); 193 ++stream; 194 *pargsCount += 1; 195 } 196 break; 197 case OpcodeByteKind_ib>>8: 198 case OpcodeByteKind_iw>>8: 199 case OpcodeByteKind_id>>8: 200 #ifdef _EM64T_ 201 case OpcodeByteKind_io>>8: 202 #endif //_EM64T_ 203 // ib, iw, id - A 1-byte (ib), 2-byte (iw), or 4-byte (id) 204 // immediate operand to the instruction that follows the 205 // opcode, ModR/M bytes or scale-indexing bytes. The opcode 206 // determines if the operand is a signed value. All words 207 // and double words are given with the low-order byte first. 208 { 209 unsigned idx = *pargsCount; 210 *pargsCount += 1; 211 assert(opnds[idx].is_imm()); 212 if (kind == OpcodeByteKind_ib) { 213 *(unsigned char*)stream = (unsigned char)opnds[idx].imm(); 214 curRelOpnd[idx] = stream; 215 stream += 1; 216 } 217 else if (kind == OpcodeByteKind_iw) { 218 *(unsigned short*)stream = (unsigned short)opnds[idx].imm(); 219 curRelOpnd[idx] = stream; 220 stream += 2; 221 } 222 else if (kind == OpcodeByteKind_id) { 223 *(unsigned*)stream = (unsigned)opnds[idx].imm(); 224 curRelOpnd[idx] = stream; 225 stream += 4; 226 } 227 #ifdef _EM64T_ 228 else { 229 assert(kind == OpcodeByteKind_io); 230 *(long long*)stream = (long long)opnds[idx].imm(); 231 curRelOpnd[idx] = stream; 232 stream += 8; 233 } 234 #else 235 else { 236 assert(false); 237 } 238 #endif 239 } 240 break; 241 case OpcodeByteKind_cb>>8: 242 assert(opnds[*pargsCount].is_imm()); 243 *(unsigned char*)stream = (unsigned char)opnds[*pargsCount].imm(); 244 curRelOpnd[*pargsCount]= stream; 245 stream += 1; 246 *pargsCount += 1; 247 break; 248 case OpcodeByteKind_cw>>8: 249 assert(opnds[*pargsCount].is_imm()); 250 *(unsigned short*)stream = (unsigned short)opnds[*pargsCount].imm(); 251 curRelOpnd[*pargsCount]= stream; 252 stream += 2; 253 *pargsCount += 1; 254 break; 255 case OpcodeByteKind_cd>>8: 256 assert(opnds[*pargsCount].is_imm()); 257 *(unsigned*)stream = (unsigned)opnds[*pargsCount].imm(); 258 curRelOpnd[*pargsCount]= stream; 259 stream += 4; 260 *pargsCount += 1; 261 break; 262 //OpcodeByteKind_cp = 0x0B00, 263 //OpcodeByteKind_co = 0x0C00, 264 //OpcodeByteKind_ct = 0x0D00, 265 case OpcodeByteKind_rb>>8: 266 case OpcodeByteKind_rw>>8: 267 case OpcodeByteKind_rd>>8: 268 // +rb, +rw, +rd - A register code, from 0 through 7, 269 // added to the hexadecimal byte given at the left of 270 // the plus sign to form a single opcode byte. 271 assert(opnds.count() > 0); 272 assert(opnds[*pargsCount].is_reg()); 273 { 274 const unsigned lowByte = (byte & OpcodeByteKind_OpcodeMask); 275 *(unsigned char*)stream = (unsigned char)lowByte + 276 getHWRegIndex(opnds[*pargsCount].reg()); 277 #ifdef _EM64T_ 278 if (opnds[*pargsCount].need_rex() && needs_rex_r(opnds[*pargsCount].reg())) { 279 prex->b = 1; 280 } 281 #endif 282 ++stream; 283 *pargsCount += 1; 284 } 285 break; 286 default: 287 assert(false); 288 break; 289 } 290 return stream; 291 } 292 293 char * EncoderBase::encode(char * stream, Mnemonic mn, const Operands& opnds) 294 { 295 #ifdef _DEBUG 296 if (opnds.count() > 0) { 297 if (opnds[0].is_mem()) { 298 assert(getRegKind(opnds[0].base()) != OpndKind_SReg); 299 } 300 else if (opnds.count() >1 && opnds[1].is_mem()) { 301 assert(getRegKind(opnds[1].base()) != OpndKind_SReg); 302 } 303 } 304 #endif 305 306 #ifdef JET_PROTO 307 char* saveStream = stream; 308 #endif 309 310 const OpcodeDesc * odesc = lookup(mn, opnds); 311 #if !defined(_EM64T_) 312 bool copy_opcode = true; 313 Rex *prex = NULL; 314 #else 315 // We need rex if 316 // either of registers used as operand or address form is new extended register 317 // it's explicitly specified by opcode 318 // So, if we don't have REX in opcode but need_rex, then set rex here 319 // otherwise, wait until opcode is set, and then update REX 320 321 bool copy_opcode = true; 322 unsigned char _1st = odesc->opcode[0]; 323 324 Rex *prex = (Rex*)stream; 325 if (opnds.need_rex() && 326 ((_1st == 0x66) || (_1st == 0xF2 || _1st == 0xF3) && odesc->opcode[1] == 0x0F)) { 327 // Special processing 328 // 329 copy_opcode = false; 330 // 331 *(unsigned char*)stream = _1st; 332 ++stream; 333 // 334 prex = (Rex*)stream; 335 prex->dummy = 4; 336 prex->w = 0; 337 prex->b = 0; 338 prex->x = 0; 339 prex->r = 0; 340 ++stream; 341 // 342 memcpy(stream, &odesc->opcode[1], odesc->opcode_len-1); 343 stream += odesc->opcode_len-1; 344 } 345 else if (_1st != 0x48 && opnds.need_rex()) { 346 prex = (Rex*)stream; 347 prex->dummy = 4; 348 prex->w = 0; 349 prex->b = 0; 350 prex->x = 0; 351 prex->r = 0; 352 ++stream; 353 } 354 #endif // ifndef EM64T 355 356 if (copy_opcode) { 357 if (odesc->opcode_len==1) { 358 *(unsigned char*)stream = *(unsigned char*)&odesc->opcode; 359 } 360 else if (odesc->opcode_len==2) { 361 *(unsigned short*)stream = *(unsigned short*)&odesc->opcode; 362 } 363 else if (odesc->opcode_len==3) { 364 *(unsigned short*)stream = *(unsigned short*)&odesc->opcode; 365 *(unsigned char*)(stream+2) = odesc->opcode[2]; 366 } 367 else if (odesc->opcode_len==4) { 368 *(unsigned*)stream = *(unsigned*)&odesc->opcode; 369 } 370 stream += odesc->opcode_len; 371 } 372 373 unsigned argsCount = odesc->first_opnd; 374 375 if (odesc->aux0) { 376 stream = encode_aux(stream, odesc->aux0, opnds, odesc, &argsCount, prex); 377 if (odesc->aux1) { 378 stream = encode_aux(stream, odesc->aux1, opnds, odesc, &argsCount, prex); 379 } 380 } 381 #ifdef JET_PROTO 382 //saveStream 383 Inst inst; 384 unsigned len = DecoderBase::decode(saveStream, &inst); 385 assert(inst.mn == mn); 386 assert(len == (unsigned)(stream-saveStream)); 387 if (mn == Mnemonic_CALL || mn == Mnemonic_JMP || 388 Mnemonic_RET == mn || 389 (Mnemonic_JO<=mn && mn<=Mnemonic_JG)) { 390 assert(inst.argc == opnds.count()); 391 392 InstructionDisassembler idi(saveStream); 393 394 for (unsigned i=0; i<inst.argc; i++) { 395 const EncoderBase::Operand& original = opnds[i]; 396 const EncoderBase::Operand& decoded = inst.operands[i]; 397 assert(original.kind() == decoded.kind()); 398 assert(original.size() == decoded.size()); 399 if (original.is_imm()) { 400 assert(original.imm() == decoded.imm()); 401 assert(idi.get_opnd(0).kind == InstructionDisassembler::Kind_Imm); 402 if (mn == Mnemonic_CALL) { 403 assert(idi.get_type() == InstructionDisassembler::RELATIVE_CALL); 404 } 405 else if (mn == Mnemonic_JMP) { 406 assert(idi.get_type() == InstructionDisassembler::RELATIVE_JUMP); 407 } 408 else if (mn == Mnemonic_RET) { 409 assert(idi.get_type() == InstructionDisassembler::RET); 410 } 411 else { 412 assert(idi.get_type() == InstructionDisassembler::RELATIVE_COND_JUMP); 413 } 414 } 415 else if (original.is_mem()) { 416 assert(original.base() == decoded.base()); 417 assert(original.index() == decoded.index()); 418 assert(original.scale() == decoded.scale()); 419 assert(original.disp() == decoded.disp()); 420 assert(idi.get_opnd(0).kind == InstructionDisassembler::Kind_Mem); 421 if (mn == Mnemonic_CALL) { 422 assert(idi.get_type() == InstructionDisassembler::INDIRECT_CALL); 423 } 424 else if (mn == Mnemonic_JMP) { 425 assert(idi.get_type() == InstructionDisassembler::INDIRECT_JUMP); 426 } 427 else { 428 assert(false); 429 } 430 } 431 else { 432 assert(original.is_reg()); 433 assert(original.reg() == decoded.reg()); 434 assert(idi.get_opnd(0).kind == InstructionDisassembler::Kind_Reg); 435 if (mn == Mnemonic_CALL) { 436 assert(idi.get_type() == InstructionDisassembler::INDIRECT_CALL); 437 } 438 else if (mn == Mnemonic_JMP) { 439 assert(idi.get_type() == InstructionDisassembler::INDIRECT_JUMP); 440 } 441 else { 442 assert(false); 443 } 444 } 445 } 446 447 Inst inst2; 448 len = DecoderBase::decode(saveStream, &inst2); 449 } 450 451 // if(idi.get_length_with_prefix() != (int)len) { 452 //__asm { int 3 }; 453 // } 454 #endif 455 456 return stream; 457 } 458 459 char* EncoderBase::encodeModRM(char* stream, const Operands& opnds, 460 unsigned idx, const OpcodeDesc * odesc, 461 Rex * prex) 462 { 463 const Operand& op = opnds[idx]; 464 assert(op.is_mem()); 465 assert(idx < COUNTOF(curRelOpnd)); 466 ModRM& modrm = *(ModRM*)stream; 467 ++stream; 468 SIB& sib = *(SIB*)stream; 469 470 // we need SIB if 471 // we have index & scale (nb: having index w/o base and w/o scale 472 // treated as error) 473 // the base is EBP w/o disp, BUT let's use a fake disp8 474 // the base is ESP (nb: cant have ESP as index) 475 476 RegName base = op.base(); 477 // only disp ?.. 478 if (base == RegName_Null && op.index() == RegName_Null) { 479 assert(op.scale() == 0); // 'scale!=0' has no meaning without index 480 // ... yes - only have disp 481 // On EM64T, the simply [disp] addressing means 'RIP-based' one - 482 // must have to use SIB to encode 'DS: based' 483 #ifdef _EM64T_ 484 modrm.mod = 0; // 00 - .. 485 modrm.rm = 4; // 100 - have SIB 486 487 sib.base = 5; // 101 - none 488 sib.index = 4; // 100 - none 489 sib.scale = 0; // 490 ++stream; // bypass SIB 491 #else 492 // ignore disp_fits8, always use disp32. 493 modrm.mod = 0; 494 modrm.rm = 5; 495 #endif 496 *(unsigned*)stream = (unsigned)op.disp(); 497 curRelOpnd[idx]= stream; 498 stream += 4; 499 return stream; 500 } 501 502 //climits: error when targeting compal 503 #define CHAR_MIN -127 504 #define CHAR_MAX 127 505 const bool disp_fits8 = CHAR_MIN <= op.disp() && op.disp() <= CHAR_MAX; 506 /*&& op.base() != RegName_Null - just checked above*/ 507 if (op.index() == RegName_Null && getHWRegIndex(op.base()) != getHWRegIndex(REG_STACK)) { 508 assert(op.scale() == 0); // 'scale!=0' has no meaning without index 509 // ... luckily no SIB, only base and may be a disp 510 511 // EBP base is a special case. Need to use [EBP] + disp8 form 512 if (op.disp() == 0 && getHWRegIndex(op.base()) != getHWRegIndex(RegName_EBP)) { 513 modrm.mod = 0; // mod=00, no disp et all 514 } 515 else if (disp_fits8) { 516 modrm.mod = 1; // mod=01, use disp8 517 *(unsigned char*)stream = (unsigned char)op.disp(); 518 curRelOpnd[idx]= stream; 519 ++stream; 520 } 521 else { 522 modrm.mod = 2; // mod=10, use disp32 523 *(unsigned*)stream = (unsigned)op.disp(); 524 curRelOpnd[idx]= stream; 525 stream += 4; 526 } 527 modrm.rm = getHWRegIndex(op.base()); 528 if (is_em64t_extra_reg(op.base())) { 529 prex->b = 1; 530 } 531 return stream; 532 } 533 534 // cool, we do have SIB. 535 ++stream; // bypass SIB in stream 536 537 // {E|R}SP cannot be scaled index, however, R12 which has the same index in modrm - can 538 assert(op.index() == RegName_Null || !equals(op.index(), REG_STACK)); 539 540 // Only GPRegs can be encoded in the SIB 541 assert(op.base() == RegName_Null || 542 getRegKind(op.base()) == OpndKind_GPReg); 543 assert(op.index() == RegName_Null || 544 getRegKind(op.index()) == OpndKind_GPReg); 545 546 modrm.rm = 4; // r/m = 100, means 'we have SIB here' 547 if (op.base() == RegName_Null) { 548 // no base. 549 // already checked above if 550 // the first if() //assert(op.index() != RegName_Null); 551 552 modrm.mod = 0; // mod=00 - here it means 'no base, but disp32' 553 sib.base = 5; // 101 with mod=00 ^^^ 554 555 // encode at least fake disp32 to avoid having [base=ebp] 556 *(unsigned*)stream = op.disp(); 557 curRelOpnd[idx]= stream; 558 stream += 4; 559 560 unsigned sc = op.scale(); 561 if (sc == 1 || sc==0) { sib.scale = 0; } // SS=00 562 else if (sc == 2) { sib.scale = 1; } // SS=01 563 else if (sc == 4) { sib.scale = 2; } // SS=10 564 else if (sc == 8) { sib.scale = 3; } // SS=11 565 sib.index = getHWRegIndex(op.index()); 566 if (is_em64t_extra_reg(op.index())) { 567 prex->x = 1; 568 } 569 570 return stream; 571 } 572 573 if (op.disp() == 0 && getHWRegIndex(op.base()) != getHWRegIndex(RegName_EBP)) { 574 modrm.mod = 0; // mod=00, no disp 575 } 576 else if (disp_fits8) { 577 modrm.mod = 1; // mod=01, use disp8 578 *(unsigned char*)stream = (unsigned char)op.disp(); 579 curRelOpnd[idx]= stream; 580 stream += 1; 581 } 582 else { 583 modrm.mod = 2; // mod=10, use disp32 584 *(unsigned*)stream = (unsigned)op.disp(); 585 curRelOpnd[idx]= stream; 586 stream += 4; 587 } 588 589 if (op.index() == RegName_Null) { 590 assert(op.scale() == 0); // 'scale!=0' has no meaning without index 591 // the only reason we're here without index, is that we have {E|R}SP 592 // or R12 as a base. Another possible reason - EBP without a disp - 593 // is handled above by adding a fake disp8 594 #ifdef _EM64T_ 595 assert(op.base() != RegName_Null && (equals(op.base(), REG_STACK) || 596 equals(op.base(), RegName_R12))); 597 #else // _EM64T_ 598 assert(op.base() != RegName_Null && equals(op.base(), REG_STACK)); 599 #endif //_EM64T_ 600 sib.scale = 0; // SS = 00 601 sib.index = 4; // SS + index=100 means 'no index' 602 } 603 else { 604 unsigned sc = op.scale(); 605 if (sc == 1 || sc==0) { sib.scale = 0; } // SS=00 606 else if (sc == 2) { sib.scale = 1; } // SS=01 607 else if (sc == 4) { sib.scale = 2; } // SS=10 608 else if (sc == 8) { sib.scale = 3; } // SS=11 609 sib.index = getHWRegIndex(op.index()); 610 if (is_em64t_extra_reg(op.index())) { 611 prex->x = 1; 612 } 613 // not an error by itself, but the usage of [index*1] instead 614 // of [base] is discouraged 615 assert(op.base() != RegName_Null || op.scale() != 1); 616 } 617 sib.base = getHWRegIndex(op.base()); 618 if (is_em64t_extra_reg(op.base())) { 619 prex->b = 1; 620 } 621 return stream; 622 } 623 624 char * EncoderBase::nops(char * stream, unsigned howMany) 625 { 626 // Recommended multi-byte NOPs from the Intel architecture manual 627 static const unsigned char nops[10][9] = { 628 { 0, }, // 0, this line is dummy and not used in the loop below 629 { 0x90, }, // 1-byte NOP 630 { 0x66, 0x90, }, // 2 631 { 0x0F, 0x1F, 0x00, }, // 3 632 { 0x0F, 0x1F, 0x40, 0x00, }, // 4 633 { 0x0F, 0x1F, 0x44, 0x00, 0x00, }, // 5 634 { 0x66, 0x0F, 0x1F, 0x44, 0x00, 0x00, }, // 6 635 { 0x0F, 0x1F, 0x80, 0x00, 0x00, 0x00, 0x00, }, // 7 636 { 0x0F, 0x1F, 0x84, 0x00, 0x00, 0x00, 0x00, 0x00, }, // 8 637 { 0x66, 0x0F, 0x1F, 0x84, 0x00, 0x00, 0x00, 0x00, 0x00 }, // 9-byte NOP 638 }; 639 640 // Start from delivering the longest possible NOPs, then proceed with shorter ones 641 for (unsigned nopSize=9; nopSize!=0; nopSize--) { 642 while(howMany>=nopSize) { 643 const unsigned char* nopBytes = nops[nopSize]; 644 for (unsigned i=0; i<nopSize; i++) { 645 stream[i] = nopBytes[i]; 646 } 647 stream += nopSize; 648 howMany -= nopSize; 649 } 650 } 651 char* end = stream + howMany; 652 return end; 653 } 654 655 char * EncoderBase::prefix(char* stream, InstPrefix pref) 656 { 657 if (pref== InstPrefix_Null) { 658 // nothing to do 659 return stream; 660 } 661 *stream = (char)pref; 662 return stream + 1; 663 } 664 665 666 /** 667 * 668 */ 669 bool EncoderBase::extAllowed(OpndExt opndExt, OpndExt instExt) { 670 if (instExt == opndExt || instExt == OpndExt_Any || opndExt == OpndExt_Any) { 671 return true; 672 } 673 //asm("int3"); 674 assert(0); 675 return false; 676 } 677 678 /** 679 * 680 */ 681 static bool match(const EncoderBase::OpcodeDesc& odesc, 682 const EncoderBase::Operands& opnds) { 683 684 assert(odesc.roles.count == opnds.count()); 685 686 for(unsigned j = 0; j < odesc.roles.count; j++) { 687 const EncoderBase::OpndDesc& desc = odesc.opnds[j]; 688 const EncoderBase::Operand& op = opnds[j]; 689 // location must match exactly 690 if ((desc.kind & op.kind()) != op.kind()) { 691 //assert(0); 692 return false; 693 } 694 // size must match exactly 695 if (desc.size != op.size()) { 696 //assert(0); 697 return false; 698 } 699 // extentions should be consistent 700 if (!EncoderBase::extAllowed(op.ext(), desc.ext)) { 701 return false; 702 } 703 } 704 return true; 705 } 706 707 708 static bool try_match(const EncoderBase::OpcodeDesc& odesc, 709 const EncoderBase::Operands& opnds, bool strict) { 710 711 assert(odesc.roles.count == opnds.count()); 712 713 for(unsigned j=0; j<odesc.roles.count; j++) { 714 // - the location must match exactly 715 if ((odesc.opnds[j].kind & opnds[j].kind()) != opnds[j].kind()) { 716 return false; 717 } 718 if (strict) { 719 // the size must match exactly 720 if (odesc.opnds[j].size != opnds[j].size()) { 721 return false; 722 } 723 } 724 else { 725 // must match only for def operands, and dont care about use ones 726 // situations like 'mov r8, imm32/mov r32, imm8' so the 727 // destination operand defines the overall size 728 if (EncoderBase::getOpndRoles(odesc.roles, j) & OpndRole_Def) { 729 if (odesc.opnds[j].size != opnds[j].size()) { 730 return false; 731 } 732 } 733 } 734 } 735 return true; 736 } 737 738 // 739 //Subhash implementaion - may be useful in case of many misses during fast 740 //opcode lookup. 741 // 742 743 #ifdef ENCODER_USE_SUBHASH 744 static unsigned subHash[32]; 745 746 static unsigned find(Mnemonic mn, unsigned hash) 747 { 748 unsigned key = hash % COUNTOF(subHash); 749 unsigned pack = subHash[key]; 750 unsigned _hash = pack & 0xFFFF; 751 if (_hash != hash) { 752 stat.miss(mn); 753 return EncoderBase::NOHASH; 754 } 755 unsigned _mn = (pack >> 24)&0xFF; 756 if (_mn != _mn) { 757 stat.miss(mn); 758 return EncoderBase::NOHASH; 759 } 760 unsigned idx = (pack >> 16) & 0xFF; 761 stat.hit(mn); 762 return idx; 763 } 764 765 static void put(Mnemonic mn, unsigned hash, unsigned idx) 766 { 767 unsigned pack = hash | (idx<<16) | (mn << 24); 768 unsigned key = hash % COUNTOF(subHash); 769 subHash[key] = pack; 770 } 771 #endif 772 773 const EncoderBase::OpcodeDesc * 774 EncoderBase::lookup(Mnemonic mn, const Operands& opnds) 775 { 776 const unsigned hash = opnds.hash(); 777 unsigned opcodeIndex = opcodesHashMap[mn][hash]; 778 #ifdef ENCODER_USE_SUBHASH 779 if (opcodeIndex == NOHASH) { 780 opcodeIndex = find(mn, hash); 781 } 782 #endif 783 784 if (opcodeIndex == NOHASH) { 785 // fast-path did no work. try to lookup sequentially 786 const OpcodeDesc * odesc = opcodes[mn]; 787 int idx = -1; 788 bool found = false; 789 for (idx=0; !odesc[idx].last; idx++) { 790 const OpcodeDesc& opcode = odesc[idx]; 791 if (opcode.platf == OpcodeInfo::decoder) { 792 continue; 793 } 794 if (opcode.roles.count != opnds.count()) { 795 continue; 796 } 797 if (try_match(opcode, opnds, true)) { 798 found = true; 799 break; 800 } 801 } 802 if (!found) { 803 for (idx=0; !odesc[idx].last; idx++) { 804 const OpcodeDesc& opcode = odesc[idx]; 805 if (opcode.platf == OpcodeInfo::decoder) { 806 continue; 807 } 808 if (opcode.roles.count != opnds.count()) { 809 continue; 810 } 811 if (try_match(opcode, opnds, false)) { 812 found = true; 813 break; 814 } 815 } 816 } 817 assert(found); 818 opcodeIndex = idx; 819 #ifdef ENCODER_USE_SUBHASH 820 put(mn, hash, opcodeIndex); 821 #endif 822 } 823 assert(opcodeIndex != NOHASH); 824 const OpcodeDesc * odesc = &opcodes[mn][opcodeIndex]; 825 assert(!odesc->last); 826 assert(odesc->roles.count == opnds.count()); 827 assert(odesc->platf != OpcodeInfo::decoder); 828 #if !defined(_EM64T_) 829 // tuning was done for IA32 only, so no size restriction on EM64T 830 //assert(sizeof(OpcodeDesc)==128); 831 #endif 832 return odesc; 833 } 834 835 char* EncoderBase::getOpndLocation(int index) { 836 assert(index < 3); 837 return curRelOpnd[index]; 838 } 839 840 841 Mnemonic EncoderBase::str2mnemonic(const char * mn_name) 842 { 843 for (unsigned m = 1; m<Mnemonic_Count; m++) { 844 if (!strcmpi(mnemonics[m].name, mn_name)) { 845 return (Mnemonic)m; 846 } 847 } 848 return Mnemonic_Null; 849 } 850 851 static const char * conditionStrings[ConditionMnemonic_Count] = { 852 "O", 853 "NO", 854 "B", 855 "AE", 856 "Z", 857 "NZ", 858 "BE", 859 "A", 860 861 "S", 862 "NS", 863 "P", 864 "NP", 865 "L", 866 "GE", 867 "LE", 868 "G", 869 }; 870 871 const char * getConditionString(ConditionMnemonic cm) { 872 return conditionStrings[cm]; 873 } 874 875 static const struct { 876 char sizeString[12]; 877 OpndSize size; 878 } 879 sizes[] = { 880 { "Sz8", OpndSize_8 }, 881 { "Sz16", OpndSize_16 }, 882 { "Sz32", OpndSize_32 }, 883 { "Sz64", OpndSize_64 }, 884 #if !defined(TESTING_ENCODER) 885 { "Sz80", OpndSize_80 }, 886 { "Sz128", OpndSize_128 }, 887 #endif 888 { "SzAny", OpndSize_Any }, 889 }; 890 891 892 OpndSize getOpndSize(const char * sizeString) 893 { 894 assert(sizeString); 895 for (unsigned i = 0; i<COUNTOF(sizes); i++) { 896 if (!strcmpi(sizeString, sizes[i].sizeString)) { 897 return sizes[i].size; 898 } 899 } 900 return OpndSize_Null; 901 } 902 903 const char * getOpndSizeString(OpndSize size) { 904 for( unsigned i = 0; i<COUNTOF(sizes); i++ ) { 905 if( sizes[i].size==size ) { 906 return sizes[i].sizeString; 907 } 908 } 909 return NULL; 910 } 911 912 static const struct { 913 char kindString[16]; 914 OpndKind kind; 915 } 916 kinds[] = { 917 { "Null", OpndKind_Null }, 918 { "GPReg", OpndKind_GPReg }, 919 { "SReg", OpndKind_SReg }, 920 { "FPReg", OpndKind_FPReg }, 921 { "XMMReg", OpndKind_XMMReg }, 922 #ifdef _HAVE_MMX_ 923 { "MMXReg", OpndKind_MMXReg }, 924 #endif 925 { "StatusReg", OpndKind_StatusReg }, 926 { "Reg", OpndKind_Reg }, 927 { "Imm", OpndKind_Imm }, 928 { "Mem", OpndKind_Mem }, 929 { "Any", OpndKind_Any }, 930 }; 931 932 const char * getOpndKindString(OpndKind kind) 933 { 934 for (unsigned i = 0; i<COUNTOF(kinds); i++) { 935 if (kinds[i].kind==kind) { 936 return kinds[i].kindString; 937 } 938 } 939 return NULL; 940 } 941 942 OpndKind getOpndKind(const char * kindString) 943 { 944 assert(kindString); 945 for (unsigned i = 0; i<COUNTOF(kinds); i++) { 946 if (!strcmpi(kindString, kinds[i].kindString)) { 947 return kinds[i].kind; 948 } 949 } 950 return OpndKind_Null; 951 } 952 953 /** 954 * A mapping between register string representation and its RegName constant. 955 */ 956 static const struct { 957 char regstring[7]; 958 RegName regname; 959 } 960 961 registers[] = { 962 #ifdef _EM64T_ 963 {"RAX", RegName_RAX}, 964 {"RBX", RegName_RBX}, 965 {"RCX", RegName_RCX}, 966 {"RDX", RegName_RDX}, 967 {"RBP", RegName_RBP}, 968 {"RSI", RegName_RSI}, 969 {"RDI", RegName_RDI}, 970 {"RSP", RegName_RSP}, 971 {"R8", RegName_R8}, 972 {"R9", RegName_R9}, 973 {"R10", RegName_R10}, 974 {"R11", RegName_R11}, 975 {"R12", RegName_R12}, 976 {"R13", RegName_R13}, 977 {"R14", RegName_R14}, 978 {"R15", RegName_R15}, 979 #endif 980 981 {"EAX", RegName_EAX}, 982 {"ECX", RegName_ECX}, 983 {"EDX", RegName_EDX}, 984 {"EBX", RegName_EBX}, 985 {"ESP", RegName_ESP}, 986 {"EBP", RegName_EBP}, 987 {"ESI", RegName_ESI}, 988 {"EDI", RegName_EDI}, 989 #ifdef _EM64T_ 990 {"R8D", RegName_R8D}, 991 {"R9D", RegName_R9D}, 992 {"R10D", RegName_R10D}, 993 {"R11D", RegName_R11D}, 994 {"R12D", RegName_R12D}, 995 {"R13D", RegName_R13D}, 996 {"R14D", RegName_R14D}, 997 {"R15D", RegName_R15D}, 998 #endif 999 1000 {"AX", RegName_AX}, 1001 {"CX", RegName_CX}, 1002 {"DX", RegName_DX}, 1003 {"BX", RegName_BX}, 1004 {"SP", RegName_SP}, 1005 {"BP", RegName_BP}, 1006 {"SI", RegName_SI}, 1007 {"DI", RegName_DI}, 1008 1009 {"AL", RegName_AL}, 1010 {"CL", RegName_CL}, 1011 {"DL", RegName_DL}, 1012 {"BL", RegName_BL}, 1013 #if !defined(_EM64T_) 1014 {"AH", RegName_AH}, 1015 {"CH", RegName_CH}, 1016 {"DH", RegName_DH}, 1017 {"BH", RegName_BH}, 1018 #else 1019 {"SPL", RegName_SPL}, 1020 {"BPL", RegName_BPL}, 1021 {"SIL", RegName_SIL}, 1022 {"DIL", RegName_DIL}, 1023 {"R8L", RegName_R8L}, 1024 {"R9L", RegName_R9L}, 1025 {"R10L", RegName_R10L}, 1026 {"R11L", RegName_R11L}, 1027 {"R12L", RegName_R12L}, 1028 {"R13L", RegName_R13L}, 1029 {"R14L", RegName_R14L}, 1030 {"R15L", RegName_R15L}, 1031 #endif 1032 {"ES", RegName_ES}, 1033 {"CS", RegName_CS}, 1034 {"SS", RegName_SS}, 1035 {"DS", RegName_DS}, 1036 {"FS", RegName_FS}, 1037 {"GS", RegName_GS}, 1038 1039 {"FP0", RegName_FP0}, 1040 /* 1041 {"FP1", RegName_FP1}, 1042 {"FP2", RegName_FP2}, 1043 {"FP3", RegName_FP3}, 1044 {"FP4", RegName_FP4}, 1045 {"FP5", RegName_FP5}, 1046 {"FP6", RegName_FP6}, 1047 {"FP7", RegName_FP7}, 1048 */ 1049 {"FP0S", RegName_FP0S}, 1050 {"FP1S", RegName_FP1S}, 1051 {"FP2S", RegName_FP2S}, 1052 {"FP3S", RegName_FP3S}, 1053 {"FP4S", RegName_FP4S}, 1054 {"FP5S", RegName_FP5S}, 1055 {"FP6S", RegName_FP6S}, 1056 {"FP7S", RegName_FP7S}, 1057 1058 {"FP0D", RegName_FP0D}, 1059 {"FP1D", RegName_FP1D}, 1060 {"FP2D", RegName_FP2D}, 1061 {"FP3D", RegName_FP3D}, 1062 {"FP4D", RegName_FP4D}, 1063 {"FP5D", RegName_FP5D}, 1064 {"FP6D", RegName_FP6D}, 1065 {"FP7D", RegName_FP7D}, 1066 1067 {"XMM0", RegName_XMM0}, 1068 {"XMM1", RegName_XMM1}, 1069 {"XMM2", RegName_XMM2}, 1070 {"XMM3", RegName_XMM3}, 1071 {"XMM4", RegName_XMM4}, 1072 {"XMM5", RegName_XMM5}, 1073 {"XMM6", RegName_XMM6}, 1074 {"XMM7", RegName_XMM7}, 1075 #ifdef _EM64T_ 1076 {"XMM8", RegName_XMM8}, 1077 {"XMM9", RegName_XMM9}, 1078 {"XMM10", RegName_XMM10}, 1079 {"XMM11", RegName_XMM11}, 1080 {"XMM12", RegName_XMM12}, 1081 {"XMM13", RegName_XMM13}, 1082 {"XMM14", RegName_XMM14}, 1083 {"XMM15", RegName_XMM15}, 1084 #endif 1085 1086 1087 {"XMM0S", RegName_XMM0S}, 1088 {"XMM1S", RegName_XMM1S}, 1089 {"XMM2S", RegName_XMM2S}, 1090 {"XMM3S", RegName_XMM3S}, 1091 {"XMM4S", RegName_XMM4S}, 1092 {"XMM5S", RegName_XMM5S}, 1093 {"XMM6S", RegName_XMM6S}, 1094 {"XMM7S", RegName_XMM7S}, 1095 #ifdef _EM64T_ 1096 {"XMM8S", RegName_XMM8S}, 1097 {"XMM9S", RegName_XMM9S}, 1098 {"XMM10S", RegName_XMM10S}, 1099 {"XMM11S", RegName_XMM11S}, 1100 {"XMM12S", RegName_XMM12S}, 1101 {"XMM13S", RegName_XMM13S}, 1102 {"XMM14S", RegName_XMM14S}, 1103 {"XMM15S", RegName_XMM15S}, 1104 #endif 1105 1106 {"XMM0D", RegName_XMM0D}, 1107 {"XMM1D", RegName_XMM1D}, 1108 {"XMM2D", RegName_XMM2D}, 1109 {"XMM3D", RegName_XMM3D}, 1110 {"XMM4D", RegName_XMM4D}, 1111 {"XMM5D", RegName_XMM5D}, 1112 {"XMM6D", RegName_XMM6D}, 1113 {"XMM7D", RegName_XMM7D}, 1114 #ifdef _EM64T_ 1115 {"XMM8D", RegName_XMM8D}, 1116 {"XMM9D", RegName_XMM9D}, 1117 {"XMM10D", RegName_XMM10D}, 1118 {"XMM11D", RegName_XMM11D}, 1119 {"XMM12D", RegName_XMM12D}, 1120 {"XMM13D", RegName_XMM13D}, 1121 {"XMM14D", RegName_XMM14D}, 1122 {"XMM15D", RegName_XMM15D}, 1123 #endif 1124 1125 {"EFLGS", RegName_EFLAGS}, 1126 }; 1127 1128 1129 const char * getRegNameString(RegName reg) 1130 { 1131 for (unsigned i = 0; i<COUNTOF(registers); i++) { 1132 if (registers[i].regname == reg) { 1133 return registers[i].regstring; 1134 } 1135 } 1136 return NULL; 1137 } 1138 1139 RegName getRegName(const char * regname) 1140 { 1141 if (NULL == regname) { 1142 return RegName_Null; 1143 } 1144 1145 for (unsigned i = 0; i<COUNTOF(registers); i++) { 1146 if (!strcmpi(regname,registers[i].regstring)) { 1147 return registers[i].regname; 1148 } 1149 } 1150 return RegName_Null; 1151 } 1152 1153 ENCODER_NAMESPACE_END 1154
