disas.c

   1 /* General "disassemble this chunk" code.  Used for debugging. */
   2 #include "config.h"
   3 #include "qemu-common.h"
   4 #include "disas/bfd.h"
   5 #include "elf.h"
   6 #include <errno.h>
   7
   8 #include "cpu.h"
   9 #include "disas/disas.h"
  10
  11 typedef struct CPUDebug {
  12     struct disassemble_info info;
  13     CPUState *cpu;
  14 } CPUDebug;
  15
  16 /* Filled in by elfload.c.  Simplistic, but will do for now. */
  17 struct syminfo *syminfos = NULL;
  18
  19 /* Get LENGTH bytes from info's buffer, at target address memaddr.
  20    Transfer them to myaddr.  */
  21 int
  22 buffer_read_memory(bfd_vma memaddr, bfd_byte *myaddr, int length,
  23                    struct disassemble_info *info)
  24 {
  25     if (memaddr < info->buffer_vma
  26         || memaddr + length > info->buffer_vma + info->buffer_length)
  27         /* Out of bounds.  Use EIO because GDB uses it.  */
  28         return EIO;
  29     memcpy (myaddr, info->buffer + (memaddr - info->buffer_vma), length);
  30     return 0;
  31 }
  32
  33 /* Get LENGTH bytes from info's buffer, at target address memaddr.
  34    Transfer them to myaddr.  */
  35 static int
  36 target_read_memory (bfd_vma memaddr,
  37                     bfd_byte *myaddr,
  38                     int length,
  39                     struct disassemble_info *info)
  40 {
  41     CPUDebug *s = container_of(info, CPUDebug, info);
  42
  43     cpu_memory_rw_debug(s->cpu, memaddr, myaddr, length, 0);
  44     return 0;
  45 }
  46
  47 /* Print an error message.  We can assume that this is in response to
  48    an error return from buffer_read_memory.  */
  49 void
  50 perror_memory (int status, bfd_vma memaddr, struct disassemble_info *info)
  51 {
  52   if (status != EIO)
  53     /* Can't happen.  */
  54     (*info->fprintf_func) (info->stream, "Unknown error %d\n", status);
  55   else
  56     /* Actually, address between memaddr and memaddr + len was
  57        out of bounds.  */
  58     (*info->fprintf_func) (info->stream,
  59                            "Address 0x%" PRIx64 " is out of bounds.\n", memaddr);
  60 }
  61
  62 /* This could be in a separate file, to save minuscule amounts of space
  63    in statically linked executables.  */
  64
  65 /* Just print the address is hex.  This is included for completeness even
  66    though both GDB and objdump provide their own (to print symbolic
  67    addresses).  */
  68
  69 void
  70 generic_print_address (bfd_vma addr, struct disassemble_info *info)
  71 {
  72     (*info->fprintf_func) (info->stream, "0x%" PRIx64, addr);
  73 }
  74
  75 /* Print address in hex, truncated to the width of a host virtual address. */
  76 static void
  77 generic_print_host_address(bfd_vma addr, struct disassemble_info *info)
  78 {
  79     uint64_t mask = ~0ULL >> (64 - (sizeof(void *) * 8));
  80     generic_print_address(addr & mask, info);
  81 }
  82
  83 /* Just return the given address.  */
  84
  85 int
  86 generic_symbol_at_address (bfd_vma addr, struct disassemble_info *info)
  87 {
  88   return 1;
  89 }
  90
  91 bfd_vma bfd_getl64 (const bfd_byte *addr)
  92 {
  93   unsigned long long v;
  94
  95   v = (unsigned long long) addr[0];
  96   v |= (unsigned long long) addr[1] << 8;
  97   v |= (unsigned long long) addr[2] << 16;
  98   v |= (unsigned long long) addr[3] << 24;
  99   v |= (unsigned long long) addr[4] << 32;
 100   v |= (unsigned long long) addr[5] << 40;
 101   v |= (unsigned long long) addr[6] << 48;
 102   v |= (unsigned long long) addr[7] << 56;
 103   return (bfd_vma) v;
 104 }
 105
 106 bfd_vma bfd_getl32 (const bfd_byte *addr)
 107 {
 108   unsigned long v;
 109
 110   v = (unsigned long) addr[0];
 111   v |= (unsigned long) addr[1] << 8;
 112   v |= (unsigned long) addr[2] << 16;
 113   v |= (unsigned long) addr[3] << 24;
 114   return (bfd_vma) v;
 115 }
 116
 117 bfd_vma bfd_getb32 (const bfd_byte *addr)
 118 {
 119   unsigned long v;
 120
 121   v = (unsigned long) addr[0] << 24;
 122   v |= (unsigned long) addr[1] << 16;
 123   v |= (unsigned long) addr[2] << 8;
 124   v |= (unsigned long) addr[3];
 125   return (bfd_vma) v;
 126 }
 127
 128 bfd_vma bfd_getl16 (const bfd_byte *addr)
 129 {
 130   unsigned long v;
 131
 132   v = (unsigned long) addr[0];
 133   v |= (unsigned long) addr[1] << 8;
 134   return (bfd_vma) v;
 135 }
 136
 137 bfd_vma bfd_getb16 (const bfd_byte *addr)
 138 {
 139   unsigned long v;
 140
 141   v = (unsigned long) addr[0] << 24;
 142   v |= (unsigned long) addr[1] << 16;
 143   return (bfd_vma) v;
 144 }
 145
 146 static int print_insn_objdump(bfd_vma pc, disassemble_info *info,
 147                               const char *prefix)
 148 {
 149     int i, n = info->buffer_length;
 150     uint8_t *buf = g_malloc(n);
 151
 152     info->read_memory_func(pc, buf, n, info);
 153
 154     for (i = 0; i < n; ++i) {
 155         if (i % 32 == 0) {
 156             info->fprintf_func(info->stream, "\n%s: ", prefix);
 157         }
 158         info->fprintf_func(info->stream, "%02x", buf[i]);
 159     }
 160
 161     g_free(buf);
 162     return n;
 163 }
 164
 165 static int print_insn_od_host(bfd_vma pc, disassemble_info *info)
 166 {
 167     return print_insn_objdump(pc, info, "OBJD-H");
 168 }
 169
 170 static int print_insn_od_target(bfd_vma pc, disassemble_info *info)
 171 {
 172     return print_insn_objdump(pc, info, "OBJD-T");
 173 }
 174
 175 /* Disassemble this for me please... (debugging). 'flags' has the following
 176    values:
 177     i386 - 1 means 16 bit code, 2 means 64 bit code
 178     ppc  - bits 0:15 specify (optionally) the machine instruction set;
 179            bit 16 indicates little endian.
 180     other targets - unused
 181  */
 182 void target_disas(FILE *out, CPUState *cpu, target_ulong code,
 183                   target_ulong size, int flags)
 184 {
 185     CPUClass *cc = CPU_GET_CLASS(cpu);
 186     target_ulong pc;
 187     int count;
 188     CPUDebug s;
 189
 190     INIT_DISASSEMBLE_INFO(s.info, out, fprintf);
 191
 192     s.cpu = cpu;
 193     s.info.read_memory_func = target_read_memory;
 194     s.info.buffer_vma = code;
 195     s.info.buffer_length = size;
 196     s.info.print_address_func = generic_print_address;
 197
 198 #ifdef TARGET_WORDS_BIGENDIAN
 199     s.info.endian = BFD_ENDIAN_BIG;
 200 #else
 201     s.info.endian = BFD_ENDIAN_LITTLE;
 202 #endif
 203
 204     if (cc->disas_set_info) {
 205         cc->disas_set_info(cpu, &s.info);
 206     }
 207
 208 #if defined(TARGET_I386)
 209     if (flags == 2) {
 210         s.info.mach = bfd_mach_x86_64;
 211     } else if (flags == 1) {
 212         s.info.mach = bfd_mach_i386_i8086;
 213     } else {
 214         s.info.mach = bfd_mach_i386_i386;
 215     }
 216     s.info.print_insn = print_insn_i386;
 217 #elif defined(TARGET_PPC)
 218     if ((flags >> 16) & 1) {
 219         s.info.endian = BFD_ENDIAN_LITTLE;
 220     }
 221     if (flags & 0xFFFF) {
 222         /* If we have a precise definition of the instruction set, use it. */
 223         s.info.mach = flags & 0xFFFF;
 224     } else {
 225 #ifdef TARGET_PPC64
 226         s.info.mach = bfd_mach_ppc64;
 227 #else
 228         s.info.mach = bfd_mach_ppc;
 229 #endif
 230     }
 231     s.info.disassembler_options = (char *)"any";
 232     s.info.print_insn = print_insn_ppc;
 233 #elif defined(TARGET_ALPHA)
 234     s.info.mach = bfd_mach_alpha_ev6;
 235     s.info.print_insn = print_insn_alpha;
 236 #endif
 237     if (s.info.print_insn == NULL) {
 238         s.info.print_insn = print_insn_od_target;
 239     }
 240
 241     for (pc = code; size > 0; pc += count, size -= count) {
 242         fprintf(out, "0x" TARGET_FMT_lx ":  ", pc);
 243         count = s.info.print_insn(pc, &s.info);
 244 #if 0
 245         {
 246             int i;
 247             uint8_t b;
 248             fprintf(out, " {");
 249             for(i = 0; i < count; i++) {
 250                 target_read_memory(pc + i, &b, 1, &s.info);
 251                 fprintf(out, " %02x", b);
 252             }
 253             fprintf(out, " }");
 254         }
 255 #endif
 256         fprintf(out, "\n");
 257         if (count < 0)
 258             break;
 259         if (size < count) {
 260             fprintf(out,
 261                     "Disassembler disagrees with translator over instruction "
 262                     "decoding\n"
 263                     "Please report this to qemu-devel@nongnu.org\n");
 264             break;
 265         }
 266     }
 267 }
 268
 269 /* Disassemble this for me please... (debugging). */
 270 void disas(FILE *out, void *code, unsigned long size)
 271 {
 272     uintptr_t pc;
 273     int count;
 274     CPUDebug s;
 275     int (*print_insn)(bfd_vma pc, disassemble_info *info) = NULL;
 276
 277     INIT_DISASSEMBLE_INFO(s.info, out, fprintf);
 278     s.info.print_address_func = generic_print_host_address;
 279
 280     s.info.buffer = code;
 281     s.info.buffer_vma = (uintptr_t)code;
 282     s.info.buffer_length = size;
 283
 284 #ifdef HOST_WORDS_BIGENDIAN
 285     s.info.endian = BFD_ENDIAN_BIG;
 286 #else
 287     s.info.endian = BFD_ENDIAN_LITTLE;
 288 #endif
 289 #if defined(CONFIG_TCG_INTERPRETER)
 290     print_insn = print_insn_tci;
 291 #elif defined(__i386__)
 292     s.info.mach = bfd_mach_i386_i386;
 293     print_insn = print_insn_i386;
 294 #elif defined(__x86_64__)
 295     s.info.mach = bfd_mach_x86_64;
 296     print_insn = print_insn_i386;
 297 #elif defined(_ARCH_PPC)
 298     s.info.disassembler_options = (char *)"any";
 299     print_insn = print_insn_ppc;
 300 #elif defined(__aarch64__) && defined(CONFIG_ARM_A64_DIS)
 301     print_insn = print_insn_arm_a64;
 302 #elif defined(__alpha__)
 303     print_insn = print_insn_alpha;
 304 #elif defined(__sparc__)
 305     print_insn = print_insn_sparc;
 306     s.info.mach = bfd_mach_sparc_v9b;
 307 #elif defined(__arm__)
 308     print_insn = print_insn_arm;
 309 #elif defined(__MIPSEB__)
 310     print_insn = print_insn_big_mips;
 311 #elif defined(__MIPSEL__)
 312     print_insn = print_insn_little_mips;
 313 #elif defined(__m68k__)
 314     print_insn = print_insn_m68k;
 315 #elif defined(__s390__)
 316     print_insn = print_insn_s390;
 317 #elif defined(__hppa__)
 318     print_insn = print_insn_hppa;
 319 #elif defined(__ia64__)
 320     print_insn = print_insn_ia64;
 321 #endif
 322     if (print_insn == NULL) {
 323         print_insn = print_insn_od_host;
 324     }
 325     for (pc = (uintptr_t)code; size > 0; pc += count, size -= count) {
 326         fprintf(out, "0x%08" PRIxPTR ":  ", pc);
 327         count = print_insn(pc, &s.info);
 328         fprintf(out, "\n");
 329         if (count < 0)
 330             break;
 331     }
 332 }
 333
 334 /* Look up symbol for debugging purpose.  Returns "" if unknown. */
 335 const char *lookup_symbol(target_ulong orig_addr)
 336 {
 337     const char *symbol = "";
 338     struct syminfo *s;
 339
 340     for (s = syminfos; s; s = s->next) {
 341         symbol = s->lookup_symbol(s, orig_addr);
 342         if (symbol[0] != '\0') {
 343             break;
 344         }
 345     }
 346
 347     return symbol;
 348 }
 349
 350 #if !defined(CONFIG_USER_ONLY)
 351
 352 #include "monitor/monitor.h"
 353
 354 static int monitor_disas_is_physical;
 355
 356 static int
 357 monitor_read_memory (bfd_vma memaddr, bfd_byte *myaddr, int length,
 358                      struct disassemble_info *info)
 359 {
 360     CPUDebug *s = container_of(info, CPUDebug, info);
 361
 362     if (monitor_disas_is_physical) {
 363         cpu_physical_memory_read(memaddr, myaddr, length);
 364     } else {
 365         cpu_memory_rw_debug(s->cpu, memaddr, myaddr, length, 0);
 366     }
 367     return 0;
 368 }
 369
 370 /* Disassembler for the monitor.
 371    See target_disas for a description of flags. */
 372 void monitor_disas(Monitor *mon, CPUState *cpu,
 373                    target_ulong pc, int nb_insn, int is_physical, int flags)
 374 {
 375     CPUClass *cc = CPU_GET_CLASS(cpu);
 376     int count, i;
 377     CPUDebug s;
 378
 379     INIT_DISASSEMBLE_INFO(s.info, (FILE *)mon, monitor_fprintf);
 380
 381     s.cpu = cpu;
 382     monitor_disas_is_physical = is_physical;
 383     s.info.read_memory_func = monitor_read_memory;
 384     s.info.print_address_func = generic_print_address;
 385
 386     s.info.buffer_vma = pc;
 387
 388 #ifdef TARGET_WORDS_BIGENDIAN
 389     s.info.endian = BFD_ENDIAN_BIG;
 390 #else
 391     s.info.endian = BFD_ENDIAN_LITTLE;
 392 #endif
 393
 394     if (cc->disas_set_info) {
 395         cc->disas_set_info(cpu, &s.info);
 396     }
 397
 398 #if defined(TARGET_I386)
 399     if (flags == 2) {
 400         s.info.mach = bfd_mach_x86_64;
 401     } else if (flags == 1) {
 402         s.info.mach = bfd_mach_i386_i8086;
 403     } else {
 404         s.info.mach = bfd_mach_i386_i386;
 405     }
 406     s.info.print_insn = print_insn_i386;
 407 #elif defined(TARGET_ALPHA)
 408     s.info.print_insn = print_insn_alpha;
 409 #elif defined(TARGET_PPC)
 410     if (flags & 0xFFFF) {
 411         /* If we have a precise definition of the instruction set, use it. */
 412         s.info.mach = flags & 0xFFFF;
 413     } else {
 414 #ifdef TARGET_PPC64
 415         s.info.mach = bfd_mach_ppc64;
 416 #else
 417         s.info.mach = bfd_mach_ppc;
 418 #endif
 419     }
 420     if ((flags >> 16) & 1) {
 421         s.info.endian = BFD_ENDIAN_LITTLE;
 422     }
 423     s.info.print_insn = print_insn_ppc;
 424 #endif
 425     if (!s.info.print_insn) {
 426         monitor_printf(mon, "0x" TARGET_FMT_lx
 427                        ": Asm output not supported on this arch\n", pc);
 428         return;
 429     }
 430
 431     for(i = 0; i < nb_insn; i++) {
 432         monitor_printf(mon, "0x" TARGET_FMT_lx ":  ", pc);
 433         count = s.info.print_insn(pc, &s.info);
 434         monitor_printf(mon, "\n");
 435         if (count < 0)
 436             break;
 437         pc += count;
 438     }
 439 }
 440 #endif