deps/lightrec/disassembler.c

   1 // SPDX-License-Identifier: LGPL-2.1-or-later
   2 /*
   3  * Copyright (C) 2014-2021 Paul Cercueil <paul@crapouillou.net>
   4  */
   5
   6 #include <stdbool.h>
   7 #include <stdio.h>
   8 #include <stdlib.h>
   9 #include <string.h>
  10
  11 #include "lightrec-private.h"
  12 #include "regcache.h"
  13
  14 static const char * const std_opcodes[] = {
  15         [OP_J]                  = "j       ",
  16         [OP_JAL]                = "jal     ",
  17         [OP_BEQ]                = "beq     ",
  18         [OP_BNE]                = "bne     ",
  19         [OP_BLEZ]               = "blez    ",
  20         [OP_BGTZ]               = "bgtz    ",
  21         [OP_ADDI]               = "addi    ",
  22         [OP_ADDIU]              = "addiu   ",
  23         [OP_SLTI]               = "slti    ",
  24         [OP_SLTIU]              = "sltiu   ",
  25         [OP_ANDI]               = "andi    ",
  26         [OP_ORI]                = "ori     ",
  27         [OP_XORI]               = "xori    ",
  28         [OP_LUI]                = "lui     ",
  29         [OP_LB]                 = "lb      ",
  30         [OP_LH]                 = "lh      ",
  31         [OP_LWL]                = "lwl     ",
  32         [OP_LW]                 = "lw      ",
  33         [OP_LBU]                = "lbu     ",
  34         [OP_LHU]                = "lhu     ",
  35         [OP_LWR]                = "lwr     ",
  36         [OP_SB]                 = "sb      ",
  37         [OP_SH]                 = "sh      ",
  38         [OP_SWL]                = "swl     ",
  39         [OP_SW]                 = "sw      ",
  40         [OP_SWR]                = "swr     ",
  41         [OP_LWC2]               = "lwc2    ",
  42         [OP_SWC2]               = "swc2    ",
  43 };
  44
  45 static const char * const special_opcodes[] = {
  46         [OP_SPECIAL_SLL]        = "sll     ",
  47         [OP_SPECIAL_SRL]        = "srl     ",
  48         [OP_SPECIAL_SRA]        = "sra     ",
  49         [OP_SPECIAL_SLLV]       = "sllv    ",
  50         [OP_SPECIAL_SRLV]       = "srlv    ",
  51         [OP_SPECIAL_SRAV]       = "srav    ",
  52         [OP_SPECIAL_JR]         = "jr      ",
  53         [OP_SPECIAL_JALR]       = "jalr    ",
  54         [OP_SPECIAL_SYSCALL]    = "syscall ",
  55         [OP_SPECIAL_BREAK]      = "break   ",
  56         [OP_SPECIAL_MFHI]       = "mfhi    ",
  57         [OP_SPECIAL_MTHI]       = "mthi    ",
  58         [OP_SPECIAL_MFLO]       = "mflo    ",
  59         [OP_SPECIAL_MTLO]       = "mtlo    ",
  60         [OP_SPECIAL_MULT]       = "mult    ",
  61         [OP_SPECIAL_MULTU]      = "multu   ",
  62         [OP_SPECIAL_DIV]        = "div     ",
  63         [OP_SPECIAL_DIVU]       = "divu    ",
  64         [OP_SPECIAL_ADD]        = "add     ",
  65         [OP_SPECIAL_ADDU]       = "addu    ",
  66         [OP_SPECIAL_SUB]        = "sub     ",
  67         [OP_SPECIAL_SUBU]       = "subu    ",
  68         [OP_SPECIAL_AND]        = "and     ",
  69         [OP_SPECIAL_OR]         = "or      ",
  70         [OP_SPECIAL_XOR]        = "xor     ",
  71         [OP_SPECIAL_NOR]        = "nor     ",
  72         [OP_SPECIAL_SLT]        = "slt     ",
  73         [OP_SPECIAL_SLTU]       = "sltu    ",
  74 };
  75
  76 static const char * const regimm_opcodes[] = {
  77         [OP_REGIMM_BLTZ]        = "bltz    ",
  78         [OP_REGIMM_BGEZ]        = "bgez    ",
  79         [OP_REGIMM_BLTZAL]      = "bltzal  ",
  80         [OP_REGIMM_BGEZAL]      = "bgezal  ",
  81 };
  82
  83 static const char * const cp0_opcodes[] = {
  84         [OP_CP0_MFC0]           = "mfc0    ",
  85         [OP_CP0_CFC0]           = "cfc0    ",
  86         [OP_CP0_MTC0]           = "mtc0    ",
  87         [OP_CP0_CTC0]           = "ctc0    ",
  88         [OP_CP0_RFE]            = "rfe",
  89 };
  90
  91 static const char * const cp2_basic_opcodes[] = {
  92         [OP_CP2_BASIC_MFC2]     = "mfc2    ",
  93         [OP_CP2_BASIC_CFC2]     = "cfc2    ",
  94         [OP_CP2_BASIC_MTC2]     = "mtc2    ",
  95         [OP_CP2_BASIC_CTC2]     = "ctc2    ",
  96 };
  97
  98 static const char * const cp2_opcodes[] = {
  99         [OP_CP2_RTPS]           = "rtps    ",
 100         [OP_CP2_NCLIP]          = "nclip   ",
 101         [OP_CP2_OP]             = "op      ",
 102         [OP_CP2_DPCS]           = "dpcs    ",
 103         [OP_CP2_INTPL]          = "intpl   ",
 104         [OP_CP2_MVMVA]          = "mvmva   ",
 105         [OP_CP2_NCDS]           = "ncds    ",
 106         [OP_CP2_CDP]            = "cdp     ",
 107         [OP_CP2_NCDT]           = "ncdt    ",
 108         [OP_CP2_NCCS]           = "nccs    ",
 109         [OP_CP2_CC]             = "cc      ",
 110         [OP_CP2_NCS]            = "ncs     ",
 111         [OP_CP2_NCT]            = "nct     ",
 112         [OP_CP2_SQR]            = "sqr     ",
 113         [OP_CP2_DCPL]           = "dcpl    ",
 114         [OP_CP2_DPCT]           = "dpct    ",
 115         [OP_CP2_AVSZ3]          = "avsz3   ",
 116         [OP_CP2_AVSZ4]          = "avsz4   ",
 117         [OP_CP2_RTPT]           = "rtpt    ",
 118         [OP_CP2_GPF]            = "gpf     ",
 119         [OP_CP2_GPL]            = "gpl     ",
 120         [OP_CP2_NCCT]           = "ncct    ",
 121 };
 122
 123 static const char * const meta_opcodes[] = {
 124         [OP_META_MOV]           = "move    ",
 125         [OP_META_EXTC]          = "extc    ",
 126         [OP_META_EXTS]          = "exts    ",
 127         [OP_META_COM]           = "com     ",
 128 };
 129
 130 static const char * const mult2_opcodes[] = {
 131         "mult2   ", "multu2  ",
 132 };
 133
 134 static const char * const opcode_flags[] = {
 135         "switched branch/DS",
 136         "sync point",
 137 };
 138
 139 static const char * const opcode_io_flags[] = {
 140         "self-modifying code",
 141         "no invalidation",
 142         "no mask",
 143         "load delay",
 144 };
 145
 146 static const char * const opcode_io_modes[] = {
 147         "Memory access",
 148         "I/O access",
 149         "RAM access",
 150         "BIOS access",
 151         "Scratchpad access",
 152         "Mapped I/O access"
 153 };
 154
 155 static const char * const opcode_branch_flags[] = {
 156         "emulate branch",
 157         "local branch",
 158 };
 159
 160 static const char * const opcode_multdiv_flags[] = {
 161         "No LO",
 162         "No HI",
 163         "No div check",
 164 };
 165
 166 static size_t do_snprintf(char *buf, size_t len, bool *first,
 167                           const char *arg1, const char *arg2)
 168 {
 169         size_t bytes;
 170
 171         if (*first)
 172                 bytes = snprintf(buf, len, "(%s%s", arg1, arg2);
 173         else
 174                 bytes = snprintf(buf, len, ", %s%s", arg1, arg2);
 175
 176         *first = false;
 177
 178         return bytes;
 179 }
 180
 181 static const char * const reg_op_token[3] = {
 182         "-", "*", "~",
 183 };
 184
 185 static int print_flags(char *buf, size_t len, const struct opcode *op,
 186                        const char * const *array, size_t array_size,
 187                        bool is_io)
 188 {
 189         const char *flag_name, *io_mode_name;
 190         unsigned int i, io_mode;
 191         size_t count = 0, bytes;
 192         bool first = true;
 193         u32 flags = op->flags;
 194         unsigned int reg_op;
 195
 196         for (i = 0; i < array_size + ARRAY_SIZE(opcode_flags); i++) {
 197                 if (!(flags & BIT(i)))
 198                         continue;
 199
 200                 if (i < ARRAY_SIZE(opcode_flags))
 201                         flag_name = opcode_flags[i];
 202                 else
 203                         flag_name = array[i - ARRAY_SIZE(opcode_flags)];
 204
 205                 bytes = do_snprintf(buf, len, &first, "", flag_name);
 206                 buf += bytes;
 207                 len -= bytes;
 208                 count += bytes;
 209         }
 210
 211         if (is_io) {
 212                 io_mode = LIGHTREC_FLAGS_GET_IO_MODE(flags);
 213                 if (io_mode > 0) {
 214                         io_mode_name = opcode_io_modes[io_mode - 1];
 215
 216                         bytes = do_snprintf(buf, len, &first, "", io_mode_name);
 217                         buf += bytes;
 218                         len -= bytes;
 219                         count += bytes;
 220                 }
 221         }
 222
 223         if (OPT_EARLY_UNLOAD) {
 224                 reg_op = LIGHTREC_FLAGS_GET_RS(flags);
 225                 if (reg_op) {
 226                         bytes = do_snprintf(buf, len, &first,
 227                                             reg_op_token[reg_op - 1],
 228                                             lightrec_reg_name(op->i.rs));
 229                         buf += bytes;
 230                         len -= bytes;
 231                         count += bytes;
 232                 }
 233
 234                 reg_op = LIGHTREC_FLAGS_GET_RT(flags);
 235                 if (reg_op) {
 236                         bytes = do_snprintf(buf, len, &first,
 237                                             reg_op_token[reg_op - 1],
 238                                             lightrec_reg_name(op->i.rt));
 239                         buf += bytes;
 240                         len -= bytes;
 241                         count += bytes;
 242                 }
 243
 244                 reg_op = LIGHTREC_FLAGS_GET_RD(flags);
 245                 if (reg_op) {
 246                         bytes = do_snprintf(buf, len, &first,
 247                                             reg_op_token[reg_op - 1],
 248                                             lightrec_reg_name(op->r.rd));
 249                         buf += bytes;
 250                         len -= bytes;
 251                         count += bytes;
 252                 }
 253         }
 254
 255         if (!first)
 256                 count += snprintf(buf, len, ")");
 257         else
 258                 *buf = '\0';
 259
 260         return count;
 261 }
 262
 263 static int print_op_special(union code c, char *buf, size_t len,
 264                             const char * const **flags_ptr, size_t *nb_flags)
 265 {
 266         switch (c.r.op) {
 267         case OP_SPECIAL_SLL:
 268         case OP_SPECIAL_SRL:
 269         case OP_SPECIAL_SRA:
 270                 return snprintf(buf, len, "%s%s,%s,%u",
 271                                 special_opcodes[c.r.op],
 272                                 lightrec_reg_name(c.r.rd),
 273                                 lightrec_reg_name(c.r.rt),
 274                                 c.r.imm);
 275         case OP_SPECIAL_SLLV:
 276         case OP_SPECIAL_SRLV:
 277         case OP_SPECIAL_SRAV:
 278         case OP_SPECIAL_ADD:
 279         case OP_SPECIAL_ADDU:
 280         case OP_SPECIAL_SUB:
 281         case OP_SPECIAL_SUBU:
 282         case OP_SPECIAL_AND:
 283         case OP_SPECIAL_OR:
 284         case OP_SPECIAL_XOR:
 285         case OP_SPECIAL_NOR:
 286         case OP_SPECIAL_SLT:
 287         case OP_SPECIAL_SLTU:
 288                 return snprintf(buf, len, "%s%s,%s,%s",
 289                                 special_opcodes[c.r.op],
 290                                 lightrec_reg_name(c.r.rd),
 291                                 lightrec_reg_name(c.r.rt),
 292                                 lightrec_reg_name(c.r.rs));
 293         case OP_SPECIAL_JR:
 294                 *flags_ptr = opcode_branch_flags;
 295                 *nb_flags = ARRAY_SIZE(opcode_branch_flags);
 296                 fallthrough;
 297         case OP_SPECIAL_MTHI:
 298         case OP_SPECIAL_MTLO:
 299                 return snprintf(buf, len, "%s%s",
 300                                 special_opcodes[c.r.op],
 301                                 lightrec_reg_name(c.r.rs));
 302         case OP_SPECIAL_JALR:
 303                 return snprintf(buf, len, "%s%s,%s",
 304                                 special_opcodes[c.r.op],
 305                                 lightrec_reg_name(c.r.rd),
 306                                 lightrec_reg_name(c.r.rs));
 307         case OP_SPECIAL_SYSCALL:
 308         case OP_SPECIAL_BREAK:
 309                 return snprintf(buf, len, "%s", special_opcodes[c.r.op]);
 310         case OP_SPECIAL_MFHI:
 311         case OP_SPECIAL_MFLO:
 312                 return snprintf(buf, len, "%s%s",
 313                                 special_opcodes[c.r.op],
 314                                 lightrec_reg_name(c.r.rd));
 315         case OP_SPECIAL_MULT:
 316         case OP_SPECIAL_MULTU:
 317         case OP_SPECIAL_DIV:
 318         case OP_SPECIAL_DIVU:
 319                 *flags_ptr = opcode_multdiv_flags;
 320                 *nb_flags = ARRAY_SIZE(opcode_multdiv_flags);
 321                 return snprintf(buf, len, "%s%s,%s,%s,%s",
 322                                 special_opcodes[c.r.op],
 323                                 lightrec_reg_name(get_mult_div_hi(c)),
 324                                 lightrec_reg_name(get_mult_div_lo(c)),
 325                                 lightrec_reg_name(c.r.rs),
 326                                 lightrec_reg_name(c.r.rt));
 327         default:
 328                 return snprintf(buf, len, "unknown (0x%08x)", c.opcode);
 329         }
 330 }
 331
 332 static int print_op_cp(union code c, char *buf, size_t len, unsigned int cp)
 333 {
 334         if (cp == 2) {
 335                 switch (c.r.op) {
 336                 case OP_CP2_BASIC:
 337                         return snprintf(buf, len, "%s%s,%u",
 338                                         cp2_basic_opcodes[c.i.rs],
 339                                         lightrec_reg_name(c.i.rt),
 340                                         c.r.rd);
 341                 default:
 342                         return snprintf(buf, len, "%s", cp2_opcodes[c.r.op]);
 343                 }
 344         } else {
 345                 switch (c.i.rs) {
 346                 case OP_CP0_MFC0:
 347                 case OP_CP0_CFC0:
 348                 case OP_CP0_MTC0:
 349                 case OP_CP0_CTC0:
 350                         return snprintf(buf, len, "%s%s,%u",
 351                                         cp0_opcodes[c.i.rs],
 352                                         lightrec_reg_name(c.i.rt),
 353                                         c.r.rd);
 354                 case OP_CP0_RFE:
 355                         return snprintf(buf, len, "rfe     ");
 356                 default:
 357                         return snprintf(buf, len, "unknown (0x%08x)", c.opcode);
 358                 }
 359         }
 360 }
 361
 362 static int print_op(union code c, u32 pc, char *buf, size_t len,
 363                     const char * const **flags_ptr, size_t *nb_flags,
 364                     bool *is_io)
 365 {
 366         if (c.opcode == 0)
 367                 return snprintf(buf, len, "nop     ");
 368
 369         switch (c.i.op) {
 370         case OP_SPECIAL:
 371                 return print_op_special(c, buf, len, flags_ptr, nb_flags);
 372         case OP_REGIMM:
 373                 *flags_ptr = opcode_branch_flags;
 374                 *nb_flags = ARRAY_SIZE(opcode_branch_flags);
 375                 return snprintf(buf, len, "%s%s,0x%x",
 376                                 regimm_opcodes[c.i.rt],
 377                                 lightrec_reg_name(c.i.rs),
 378                                 pc + 4 + ((s16)c.i.imm << 2));
 379         case OP_J:
 380         case OP_JAL:
 381                 *flags_ptr = opcode_branch_flags;
 382                 *nb_flags = ARRAY_SIZE(opcode_branch_flags);
 383                 return snprintf(buf, len, "%s0x%x",
 384                                 std_opcodes[c.i.op],
 385                                 (pc & 0xf0000000) | (c.j.imm << 2));
 386         case OP_BEQ:
 387                 if (c.i.rs == c.i.rt) {
 388                         *flags_ptr = opcode_branch_flags;
 389                         *nb_flags = ARRAY_SIZE(opcode_branch_flags);
 390                         return snprintf(buf, len, "b       0x%x",
 391                                         pc + 4 + ((s16)c.i.imm << 2));
 392                 }
 393                 fallthrough;
 394         case OP_BNE:
 395         case OP_BLEZ:
 396         case OP_BGTZ:
 397                 *flags_ptr = opcode_branch_flags;
 398                 *nb_flags = ARRAY_SIZE(opcode_branch_flags);
 399                 return snprintf(buf, len, "%s%s,%s,0x%x",
 400                                 std_opcodes[c.i.op],
 401                                 lightrec_reg_name(c.i.rs),
 402                                 lightrec_reg_name(c.i.rt),
 403                                 pc + 4 + ((s16)c.i.imm << 2));
 404         case OP_ADDI:
 405         case OP_ADDIU:
 406         case OP_SLTI:
 407         case OP_SLTIU:
 408         case OP_ANDI:
 409         case OP_ORI:
 410         case OP_XORI:
 411                 return snprintf(buf, len, "%s%s,%s,0x%04hx",
 412                                 std_opcodes[c.i.op],
 413                                 lightrec_reg_name(c.i.rt),
 414                                 lightrec_reg_name(c.i.rs),
 415                                 (u16)c.i.imm);
 416
 417         case OP_LUI:
 418                 return snprintf(buf, len, "%s%s,0x%04hx",
 419                                 std_opcodes[c.i.op],
 420                                 lightrec_reg_name(c.i.rt),
 421                                 (u16)c.i.imm);
 422         case OP_CP0:
 423                 return print_op_cp(c, buf, len, 0);
 424         case OP_CP2:
 425                 return print_op_cp(c, buf, len, 2);
 426         case OP_LB:
 427         case OP_LH:
 428         case OP_LWL:
 429         case OP_LW:
 430         case OP_LBU:
 431         case OP_LHU:
 432         case OP_LWR:
 433         case OP_SB:
 434         case OP_SH:
 435         case OP_SWL:
 436         case OP_SW:
 437         case OP_SWR:
 438                 *flags_ptr = opcode_io_flags;
 439                 *nb_flags = ARRAY_SIZE(opcode_io_flags);
 440                 *is_io = true;
 441                 return snprintf(buf, len, "%s%s,%hd(%s)",
 442                                 std_opcodes[c.i.op],
 443                                 lightrec_reg_name(c.i.rt),
 444                                 (s16)c.i.imm,
 445                                 lightrec_reg_name(c.i.rs));
 446         case OP_LWC2:
 447         case OP_SWC2:
 448                 *flags_ptr = opcode_io_flags;
 449                 *nb_flags = ARRAY_SIZE(opcode_io_flags);
 450                 return snprintf(buf, len, "%s%s,%hd(%s)",
 451                                 std_opcodes[c.i.op],
 452                                 lightrec_reg_name(c.i.rt),
 453                                 (s16)c.i.imm,
 454                                 lightrec_reg_name(c.i.rs));
 455         case OP_META:
 456                 return snprintf(buf, len, "%s%s,%s",
 457                                 meta_opcodes[c.m.op],
 458                                 lightrec_reg_name(c.m.rd),
 459                                 lightrec_reg_name(c.m.rs));
 460         case OP_META_MULT2:
 461         case OP_META_MULTU2:
 462                 *flags_ptr = opcode_multdiv_flags;
 463                 *nb_flags = ARRAY_SIZE(opcode_multdiv_flags);
 464                 return snprintf(buf, len, "%s%s,%s,%s,%u",
 465                                 mult2_opcodes[c.i.op == OP_META_MULTU2],
 466                                 lightrec_reg_name(get_mult_div_hi(c)),
 467                                 lightrec_reg_name(get_mult_div_lo(c)),
 468                                 lightrec_reg_name(c.r.rs), c.r.op);
 469         default:
 470                 return snprintf(buf, len, "unknown (0x%08x)", c.opcode);
 471         }
 472 }
 473
 474 void lightrec_print_disassembly(const struct block *block, const u32 *code_ptr)
 475 {
 476         const struct opcode *op;
 477         const char * const *flags_ptr;
 478         size_t nb_flags, count, count2;
 479         char buf[256], buf2[256], buf3[256];
 480         unsigned int i;
 481         u32 pc, branch_pc, code;
 482         bool is_io;
 483
 484         for (i = 0; i < block->nb_ops; i++) {
 485                 op = &block->opcode_list[i];
 486                 branch_pc = get_branch_pc(block, i, 0);
 487                 pc = block->pc + (i << 2);
 488                 code = LE32TOH(code_ptr[i]);
 489
 490                 count = print_op((union code)code, pc, buf, sizeof(buf),
 491                                  &flags_ptr, &nb_flags, &is_io);
 492
 493                 flags_ptr = NULL;
 494                 nb_flags = 0;
 495                 is_io = false;
 496                 count2 = print_op(op->c, branch_pc, buf2, sizeof(buf2),
 497                                   &flags_ptr, &nb_flags, &is_io);
 498
 499                 if (code == op->c.opcode) {
 500                         *buf2 = '\0';
 501                         count2 = 0;
 502                 }
 503
 504                 print_flags(buf3, sizeof(buf3), op, flags_ptr, nb_flags, is_io);
 505
 506                 printf("0x%08x (0x%x)\t%s%*c%s%*c%s\n", pc, i << 2,
 507                        buf, 30 - (int)count, ' ', buf2, 30 - (int)count2, ' ', buf3);
 508         }
 509 }