msp430-decode.opc revision 1.4
1 /* -*- c -*- */ 2 /* Copyright (C) 2013-2018 Free Software Foundation, Inc. 3 Contributed by Red Hat. 4 Written by DJ Delorie. 5 6 This file is part of the GNU opcodes library. 7 8 This library is free software; you can redistribute it and/or modify 9 it under the terms of the GNU General Public License as published by 10 the Free Software Foundation; either version 3, or (at your option) 11 any later version. 12 13 It is distributed in the hope that it will be useful, but WITHOUT 14 ANY WARRANTY; without even the implied warranty of MERCHANTABILITY 15 or FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public 16 License for more details. 17 18 You should have received a copy of the GNU General Public License 19 along with this program; if not, write to the Free Software 20 Foundation, Inc., 51 Franklin Street - Fifth Floor, Boston, 21 MA 02110-1301, USA. */ 22 23 #include "sysdep.h" 24 #include <stdio.h> 25 #include <stdlib.h> 26 #include <string.h> 27 #include "bfd.h" 28 #include "opintl.h" 29 #include "opcode/msp430-decode.h" 30 31 static int trace = 0; 32 33 typedef struct 34 { 35 MSP430_Opcode_Decoded *msp430; 36 int (*getbyte)(void *); 37 void *ptr; 38 unsigned char *op; 39 int op_ptr; 40 int pc; 41 } LocalData; 42 43 #define AU ATTRIBUTE_UNUSED 44 #define GETBYTE() getbyte_swapped (ld) 45 #define B ((unsigned long) GETBYTE ()) 46 47 static int 48 getbyte_swapped (LocalData *ld) 49 { 50 int b; 51 52 if (ld->op_ptr == ld->msp430->n_bytes) 53 { 54 do 55 { 56 b = ld->getbyte (ld->ptr); 57 ld->op [(ld->msp430->n_bytes++)^1] = b; 58 } 59 while (ld->msp430->n_bytes & 1); 60 } 61 return ld->op[ld->op_ptr++]; 62 } 63 64 #define ID(x) msp430->id = x 65 66 #define OP(n, t, r, a) (msp430->op[n].type = t, \ 67 msp430->op[n].reg = r, \ 68 msp430->op[n].addend = a) 69 70 #define OPX(n, t, r1, r2, a) \ 71 (msp430->op[n].type = t, \ 72 msp430->op[n].reg = r1, \ 73 msp430->op[n].reg2 = r2, \ 74 msp430->op[n].addend = a) 75 76 #define SYNTAX(x) msp430->syntax = x 77 #define UNSUPPORTED() msp430->syntax = "*unknown*" 78 79 #define DC(c) OP (0, MSP430_Operand_Immediate, 0, c) 80 #define DR(r) OP (0, MSP430_Operand_Register, r, 0) 81 #define DM(r, a) OP (0, MSP430_Operand_Indirect, r, a) 82 #define DA(a) OP (0, MSP430_Operand_Indirect, MSR_None, a) 83 #define AD(r, ad) encode_ad (r, ad, ld, 0) 84 #define ADX(r, ad, x) encode_ad (r, ad, ld, x) 85 86 #define SC(c) OP (1, MSP430_Operand_Immediate, 0, c) 87 #define SR(r) OP (1, MSP430_Operand_Register, r, 0) 88 #define SM(r, a) OP (1, MSP430_Operand_Indirect, r, a) 89 #define SA(a) OP (1, MSP430_Operand_Indirect, MSR_None, a) 90 #define SI(r) OP (1, MSP430_Operand_Indirect_Postinc, r, 0) 91 #define AS(r, as) encode_as (r, as, ld, 0) 92 #define ASX(r, as, x) encode_as (r, as, ld, x) 93 94 #define BW(x) msp430->size = (x ? 8 : 16) 95 /* The last 20 is for SWPBX.Z and SXTX.A. */ 96 #define ABW(a,x) msp430->size = (a ? ((x ? 8 : 16)) : (x ? 20 : 20)) 97 98 #define IMMU(bytes) immediate (bytes, 0, ld) 99 #define IMMS(bytes) immediate (bytes, 1, ld) 100 101 /* Helper macros for known status bits settings. */ 102 #define F_____ msp430->flags_1 = msp430->flags_0 = 0; msp430->flags_set = 0 103 #define F_VNZC msp430->flags_1 = msp430->flags_0 = 0; msp430->flags_set = 0x87 104 #define F_0NZC msp430->flags_1 = 0; msp430->flags_0 = 0x80; msp430->flags_set = 0x07 105 106 107 /* The chip is little-endian, but GETBYTE byte-swaps words because the 108 decoder is based on 16-bit "words" so *this* logic is big-endian. */ 109 110 static int 111 immediate (int bytes, int sign_extend, LocalData *ld) 112 { 113 unsigned long i = 0; 114 115 switch (bytes) 116 { 117 case 1: 118 i |= B; 119 if (sign_extend && (i & 0x80)) 120 i -= 0x100; 121 break; 122 case 2: 123 i |= B << 8; 124 i |= B; 125 if (sign_extend && (i & 0x8000)) 126 i -= 0x10000; 127 break; 128 case 3: 129 i |= B << 16; 130 i |= B << 8; 131 i |= B; 132 if (sign_extend && (i & 0x800000)) 133 i -= 0x1000000; 134 break; 135 case 4: 136 i |= B << 24; 137 i |= B << 16; 138 i |= B << 8; 139 i |= B; 140 if (sign_extend && (i & 0x80000000ULL)) 141 i -= 0x100000000ULL; 142 break; 143 default: 144 opcodes_error_handler 145 (_("internal error: immediate() called with invalid byte count %d"), 146 bytes); 147 abort (); 148 } 149 return i; 150 } 151 152 /* 153 PC SP SR CG 154 As 155 00 Rn - - R2 #0 156 01 X(Rn) Sym - X(abs) #1 157 10 (Rn) - - #4 #2 158 11 (Rn++) #imm - #8 #-1 159 160 Ad 161 0 Rn - - - - 162 1 X(Rn) Sym - X(abs) - */ 163 164 static void 165 encode_ad (int reg, int ad, LocalData *ld, int ext) 166 { 167 MSP430_Opcode_Decoded *msp430 = ld->msp430; 168 169 if (ad) 170 { 171 int x = IMMU(2) | (ext << 16); 172 switch (reg) 173 { 174 case 0: /* (PC) -> Symbolic. */ 175 DA (x + ld->pc + ld->op_ptr - 2); 176 break; 177 case 2: /* (SR) -> Absolute. */ 178 DA (x); 179 break; 180 default: 181 DM (reg, x); 182 break; 183 } 184 } 185 else 186 { 187 DR (reg); 188 } 189 } 190 191 static void 192 encode_as (int reg, int as, LocalData *ld, int ext) 193 { 194 MSP430_Opcode_Decoded *msp430 = ld->msp430; 195 int x; 196 197 switch (as) 198 { 199 case 0: 200 switch (reg) 201 { 202 case 3: 203 SC (0); 204 break; 205 default: 206 SR (reg); 207 break; 208 } 209 break; 210 case 1: 211 switch (reg) 212 { 213 case 0: /* PC -> Symbolic. */ 214 x = IMMU(2) | (ext << 16); 215 SA (x + ld->pc + ld->op_ptr - 2); 216 break; 217 case 2: /* SR -> Absolute. */ 218 x = IMMU(2) | (ext << 16); 219 SA (x); 220 break; 221 case 3: 222 SC (1); 223 break; 224 default: 225 x = IMMU(2) | (ext << 16); 226 SM (reg, x); 227 break; 228 } 229 break; 230 case 2: 231 switch (reg) 232 { 233 case 2: 234 SC (4); 235 break; 236 case 3: 237 SC (2); 238 break; 239 case MSR_None: 240 SA (0); 241 break; 242 default: 243 SM (reg, 0); 244 break; 245 } 246 break; 247 case 3: 248 switch (reg) 249 { 250 case 0: 251 { 252 /* This fetch *is* the *PC++ that the opcode encodes :-) */ 253 x = IMMU(2) | (ext << 16); 254 SC (x); 255 } 256 break; 257 case 2: 258 SC (8); 259 break; 260 case 3: 261 SC (-1); 262 break; 263 default: 264 SI (reg); 265 break; 266 } 267 break; 268 } 269 } 270 271 static void 272 encode_rep_zc (int srxt, int dsxt, LocalData *ld) 273 { 274 MSP430_Opcode_Decoded *msp430 = ld->msp430; 275 276 msp430->repeat_reg = srxt & 1; 277 msp430->repeats = dsxt; 278 msp430->zc = (srxt & 2) ? 1 : 0; 279 } 280 281 #define REPZC(s,d) encode_rep_zc (s, d, ld) 282 283 static int 284 dopc_to_id (int dopc) 285 { 286 switch (dopc) 287 { 288 case 4: return MSO_mov; 289 case 5: return MSO_add; 290 case 6: return MSO_addc; 291 case 7: return MSO_subc; 292 case 8: return MSO_sub; 293 case 9: return MSO_cmp; 294 case 10: return MSO_dadd; 295 case 11: return MSO_bit; 296 case 12: return MSO_bic; 297 case 13: return MSO_bis; 298 case 14: return MSO_xor; 299 case 15: return MSO_and; 300 default: return MSO_unknown; 301 } 302 } 303 304 static int 305 sopc_to_id (int sop, int c) 306 { 307 switch (sop * 2 + c) 308 { 309 case 0: return MSO_rrc; 310 case 1: return MSO_swpb; 311 case 2: return MSO_rra; 312 case 3: return MSO_sxt; 313 case 4: return MSO_push; 314 case 5: return MSO_call; 315 case 6: return MSO_reti; 316 default: return MSO_unknown; 317 } 318 } 319 320 int 321 msp430_decode_opcode (unsigned long pc, 322 MSP430_Opcode_Decoded *msp430, 323 int (*getbyte)(void *), 324 void *ptr) 325 { 326 LocalData lds, *ld = &lds; 327 unsigned char op_buf[20] = {0}; 328 unsigned char *op = op_buf; 329 int raddr; 330 int al_bit; 331 int srxt_bits, dsxt_bits; 332 333 lds.msp430 = msp430; 334 lds.getbyte = getbyte; 335 lds.ptr = ptr; 336 lds.op = op; 337 lds.op_ptr = 0; 338 lds.pc = pc; 339 340 memset (msp430, 0, sizeof (*msp430)); 341 342 /* These are overridden by an extension word. */ 343 al_bit = 1; 344 srxt_bits = 0; 345 dsxt_bits = 0; 346 347 post_extension_word: 348 ; 349 350 /* 430X extention word. */ 351 /** 0001 1srx t l 00 dsxt 430x */ 352 353 al_bit = l; 354 srxt_bits = srx * 2 + t; 355 dsxt_bits = dsxt; 356 op = op_buf + lds.op_ptr; 357 msp430->ofs_430x = 1; 358 goto post_extension_word; 359 360 /* double-op insns: 361 opcode:4 sreg:4 Ad:1 BW:1 As:2 Dreg:4 362 363 single-op insn: 364 opcode:9 BW:1 Ad:2 DSreg:4 365 366 jumps: 367 opcode:3 Cond:3 pcrel:10. */ 368 369 /* Double-Operand "opcode" fields. */ 370 /** VARY dopc 0100 0101 0110 0111 1000 1001 1010 1011 1100 1101 1110 1111 */ 371 372 /** dopc sreg a b as dreg %D%b %1,%0 */ 373 374 ID (dopc_to_id (dopc)); ASX (sreg, as, srxt_bits); ADX (dreg, a, dsxt_bits); ABW (al_bit, b); 375 if (a == 0 && as == 0) 376 REPZC (srxt_bits, dsxt_bits); 377 378 switch (msp430->id) 379 { 380 case MSO_mov: F_____; break; 381 case MSO_add: F_VNZC; break; 382 case MSO_addc: F_VNZC; break; 383 case MSO_subc: F_VNZC; break; 384 case MSO_sub: F_VNZC; break; 385 case MSO_cmp: F_VNZC; break; 386 case MSO_dadd: F_VNZC; break; 387 case MSO_bit: F_0NZC; break; 388 case MSO_bic: F_____; break; 389 case MSO_bis: F_____; break; 390 case MSO_xor: F_VNZC; break; 391 case MSO_and: F_0NZC; break; 392 default: break; 393 } 394 395 /** 0001 00so c b ad dreg %S%b %1 */ 396 397 ID (sopc_to_id (so,c)); ASX (dreg, ad, srxt_bits); ABW (al_bit, b); 398 399 if (ad == 0) 400 REPZC (srxt_bits, dsxt_bits); 401 402 /* The helper functions encode for source, but it's 403 both source and dest, with a few documented exceptions. */ 404 msp430->op[0] = msp430->op[1]; 405 406 /* RETI ignores the operand. */ 407 if (msp430->id == MSO_reti) 408 msp430->syntax = "%S"; 409 410 switch (msp430->id) 411 { 412 case MSO_rrc: F_VNZC; break; 413 case MSO_swpb: F_____; break; 414 case MSO_rra: F_0NZC; break; 415 case MSO_sxt: F_0NZC; break; 416 case MSO_push: F_____; break; 417 case MSO_call: F_____; break; 418 case MSO_reti: F_VNZC; break; 419 default: break; 420 } 421 422 /* 20xx 0010 0000 ---- ---- 423 3cxx 0011 1100 ---- ---- 424 001j mp-- ---- ----. */ 425 /** 001jmp aa addrlsbs %J %1 */ 426 427 raddr = (aa << 9) | (addrlsbs << 1); 428 if (raddr & 0x400) 429 raddr = raddr - 0x800; 430 /* This is a pc-relative jump, but we don't use SM because that 431 would load the target address from the memory at X(PC), not use 432 PC+X *as* the address. So we use SC to use the address, not the 433 data at that address. */ 434 ID (MSO_jmp); SC (pc + raddr + msp430->n_bytes); 435 msp430->cond = jmp; 436 437 /* Extended instructions. */ 438 439 /** 0000 srcr 0000 dstr MOVA @%1, %0 */ 440 ID (MSO_mov); SM (srcr, 0); DR (dstr); 441 msp430->size = 20; 442 msp430->ofs_430x = 1; 443 444 /** 0000 srcr 0001 dstr MOVA @%1+, %0 */ 445 ID (MSO_mov); SI (srcr); DR (dstr); 446 msp430->size = 20; 447 msp430->ofs_430x = 1; 448 449 /** 0000 srcr 0010 dstr MOVA &%1, %0 */ 450 ID (MSO_mov); SA ((srcr << 16) + IMMU(2)); DR (dstr); 451 msp430->size = 20; 452 msp430->ofs_430x = 1; 453 454 /** 0000 srcr 0011 dstr MOVA %1, %0 */ 455 ID (MSO_mov); SM (srcr, IMMS(2)); DR (dstr); 456 msp430->size = 20; 457 msp430->ofs_430x = 1; 458 459 /** 0000 srcr 0110 dstr MOVA %1, &%0 */ 460 ID (MSO_mov); SR (srcr); DA ((dstr << 16) + IMMU(2)); 461 msp430->size = 20; 462 msp430->ofs_430x = 1; 463 464 /** 0000 srcr 0111 dstr MOVA %1, &%0 */ 465 ID (MSO_mov); SR (srcr); DM (dstr, IMMS(2)); 466 msp430->size = 20; 467 msp430->ofs_430x = 1; 468 469 /** 0000 srcr 1000 dstr MOVA %1, %0 */ 470 ID (MSO_mov); SC ((srcr << 16) + IMMU(2)); DR (dstr); 471 msp430->size = 20; 472 msp430->ofs_430x = 1; 473 474 /** 0000 srcr 1001 dstr CMPA %1, %0 */ 475 ID (MSO_cmp); SC ((srcr << 16) + IMMU(2)); DR (dstr); 476 msp430->size = 20; 477 msp430->ofs_430x = 1; 478 F_VNZC; 479 480 /** 0000 srcr 1010 dstr ADDA %1, %0 */ 481 ID (MSO_add); SC ((srcr << 16) + IMMU(2)); DR (dstr); 482 msp430->size = 20; 483 msp430->ofs_430x = 1; 484 F_VNZC; 485 486 /** 0000 srcr 1011 dstr SUBA %1, %0 */ 487 ID (MSO_sub); SC ((srcr << 16) + IMMU(2)); DR (dstr); 488 msp430->size = 20; 489 msp430->ofs_430x = 1; 490 F_VNZC; 491 492 /** 0000 srcr 1011 dstr SUBA %1, %0 */ 493 ID (MSO_sub); SC ((srcr << 16) + IMMU(2)); DR (dstr); 494 msp430->size = 20; 495 msp430->ofs_430x = 1; 496 F_VNZC; 497 498 /** 0000 srcr 1100 dstr MOVA %1, %0 */ 499 ID (MSO_mov); SR (srcr); DR (dstr); 500 msp430->size = 20; 501 msp430->ofs_430x = 1; 502 503 /** 0000 srcr 1101 dstr CMPA %1, %0 */ 504 ID (MSO_cmp); SR (srcr); DR (dstr); 505 msp430->size = 20; 506 msp430->ofs_430x = 1; 507 F_VNZC; 508 509 /** 0000 srcr 1110 dstr ADDA %1, %0 */ 510 ID (MSO_add); SR (srcr); DR (dstr); 511 msp430->size = 20; 512 msp430->ofs_430x = 1; 513 F_VNZC; 514 515 /** 0000 srcr 1111 dstr SUBA %1, %0 */ 516 ID (MSO_sub); SR (srcr); DR (dstr); 517 msp430->size = 20; 518 msp430->ofs_430x = 1; 519 F_VNZC; 520 521 /** 0000 bt00 010w dstr RRCM.A %c, %0 */ 522 ID (MSO_rrc); DR (dstr); SR (dstr); 523 msp430->repeats = bt; 524 msp430->size = w ? 16 : 20; 525 msp430->ofs_430x = 1; 526 F_0NZC; 527 528 /** 0000 bt01 010w dstr RRAM.A %c, %0 */ 529 ID (MSO_rra); DR (dstr); SR (dstr); 530 msp430->repeats = bt; 531 msp430->size = w ? 16 : 20; 532 msp430->ofs_430x = 1; 533 F_0NZC; 534 535 /** 0000 bt10 010w dstr RLAM.A %c, %0 */ 536 ID (MSO_add); DR (dstr); SR (dstr); 537 msp430->repeats = bt; 538 msp430->size = w ? 16 : 20; 539 msp430->ofs_430x = 1; 540 F_0NZC; 541 542 /** 0000 bt11 010w dstr RRUM.A %c, %0 */ 543 ID (MSO_rru); DR (dstr); SR (dstr); 544 msp430->repeats = bt; 545 msp430->size = w ? 16 : 20; 546 msp430->ofs_430x = 1; 547 F_0NZC; 548 549 /** 0001 0011 0000 0000 RETI */ 550 ID (MSO_reti); 551 msp430->size = 20; 552 msp430->ofs_430x = 1; 553 554 /** 0001 0011 01as dstr CALLA %0 */ 555 ID (MSO_call); AS (dstr, as); 556 msp430->size = 20; 557 msp430->ofs_430x = 1; 558 559 /** 0001 0011 1000 extb CALLA %0 */ 560 ID (MSO_call); SA (IMMU(2) | (extb << 16)); 561 msp430->size = 20; 562 msp430->ofs_430x = 1; 563 564 /** 0001 0011 1001 extb CALLA %0 */ 565 raddr = IMMU(2) | (extb << 16); 566 if (raddr & 0x80000) 567 raddr -= 0x100000; 568 ID (MSO_call); SA (pc + raddr + msp430->n_bytes); 569 msp430->size = 20; 570 msp430->ofs_430x = 1; 571 572 /** 0001 0011 1011 extb CALLA %0 */ 573 ID (MSO_call); SC (IMMU(2) | (extb << 16)); 574 msp430->size = 20; 575 msp430->ofs_430x = 1; 576 577 /** 0001 010w bits srcr PUSHM.A %0 */ 578 ID (MSO_push); SR (srcr); 579 msp430->size = w ? 16 : 20; 580 msp430->repeats = bits; 581 msp430->ofs_430x = 1; 582 583 /** 0001 011w bits dstr POPM.A %0 */ 584 ID (MSO_pop); DR (dstr); 585 msp430->size = w ? 16 : 20; 586 msp430->repeats = bits; 587 msp430->ofs_430x = 1; 588 589 /** */ 590 591 return msp430->n_bytes; 592 } 593
Indexes created Sun Mar 01 05:31:48 UTC 2026