deps/lightning/lib/jit_disasm.c

   1 /*
   2  * Copyright (C) 2012-2019  Free Software Foundation, Inc.
   3  *
   4  * This file is part of GNU lightning.
   5  *
   6  * GNU lightning is free software; you can redistribute it and/or modify it
   7  * under the terms of the GNU Lesser General Public License as published
   8  * by the Free Software Foundation; either version 3, or (at your option)
   9  * any later version.
  10  *
  11  * GNU lightning is distributed in the hope that it will be useful, but
  12  * WITHOUT ANY WARRANTY; without even the implied warranty of MERCHANTABILITY
  13  * or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU Lesser General Public
  14  * License for more details.
  15  *
  16  * Authors:
  17  *      Paulo Cesar Pereira de Andrade
  18  */
  19
  20 #include <lightning.h>
  21 #include <lightning/jit_private.h>
  22 #if DISASSEMBLER
  23 #  include <dis-asm.h>
  24 #endif
  25
  26 /*
  27  * Prototypes
  28  */
  29 #if DISASSEMBLER
  30 static int
  31 disasm_compare_symbols(const void *ap, const void *bp);
  32
  33 static void
  34 disasm_print_address(bfd_vma addr, struct disassemble_info *info);
  35
  36 #define disassemble(u, v)       _disassemble(_jit, u, v)
  37 static void
  38 _disassemble(jit_state_t *_jit, jit_pointer_t code, jit_int32_t length);
  39 #endif
  40
  41 /*
  42  * Initialization
  43  */
  44 #if DISASSEMBLER
  45 static bfd                       *disasm_bfd;
  46 static disassemble_info           disasm_info;
  47 static disassembler_ftype         disasm_print;
  48 static asymbol                  **disasm_symbols;
  49 static asymbol                   *disasm_synthetic;
  50 static long                       disasm_num_symbols;
  51 static long                       disasm_num_synthetic;
  52 static jit_state_t               *disasm_jit;
  53 static FILE                      *disasm_stream;
  54 #endif
  55
  56 #if BINUTILS_2_38
  57 static int fprintf_styled(void *, enum disassembler_style, const char* fmt, ...)
  58 {
  59   va_list args;
  60   int r;
  61
  62   va_start(args, fmt);
  63   r = vprintf(fmt, args);
  64   va_end(args);
  65
  66   return r;
  67 }
  68 #endif
  69
  70 /*
  71  * Implementation
  72  */
  73 void
  74 jit_init_debug(const char *progname)
  75 {
  76     jit_init_print();
  77 #if DISASSEMBLER
  78     bfd_init();
  79
  80     if (progname)
  81         disasm_bfd = bfd_openr(progname, NULL);
  82     if (disasm_bfd == NULL) {
  83 #if defined(__linux__)
  84         disasm_bfd = bfd_openr("/proc/self/exe", NULL);
  85         if (disasm_bfd == NULL)
  86 #endif
  87             return;
  88     }
  89     bfd_check_format(disasm_bfd, bfd_object);
  90     bfd_check_format(disasm_bfd, bfd_archive);
  91     if (!disasm_stream)
  92         disasm_stream = stdout;
  93
  94 #if BINUTILS_2_38
  95     INIT_DISASSEMBLE_INFO(disasm_info, disasm_stream, fprintf, fprintf_styled);
  96 #else
  97     INIT_DISASSEMBLE_INFO(disasm_info, disasm_stream, fprintf);
  98 #endif
  99     disasm_info.arch = bfd_get_arch(disasm_bfd);
 100     disasm_info.mach = bfd_get_mach(disasm_bfd);
 101
 102 #  if HAVE_DISASSEMBLE_INIT_FOR_TARGET
 103     disassemble_init_for_target(&disasm_info);
 104 #  endif
 105
 106 #  if defined(__powerpc64__)
 107     disasm_info.disassembler_options = "64";
 108 #  endif
 109 #  if defined(__sparc__) || defined(__s390__) || defined(__s390x__)
 110     disasm_info.endian = disasm_info.display_endian = BFD_ENDIAN_BIG;
 111 #  endif
 112 #  if defined(__s390__) || defined(__s390x__)
 113     disasm_info.disassembler_options = "zarch";
 114 #  endif
 115     disasm_info.print_address_func = disasm_print_address;
 116
 117 # if BINUTILS_2_29
 118     disasm_print = disassembler(disasm_info.arch, __BYTE_ORDER == __BIG_ENDIAN,
 119                                 disasm_info.mach, disasm_bfd);
 120 #  else
 121     disasm_print = disassembler(disasm_bfd);
 122 #  endif
 123     assert(disasm_print);
 124
 125     if (bfd_get_file_flags(disasm_bfd) & HAS_SYMS) {
 126         asymbol         **in;
 127         asymbol         **out;
 128         asymbol          *symbol;
 129         long              offset;
 130         long              sym_count;
 131         long              dyn_count;
 132         long              sym_storage;
 133         long              dyn_storage;
 134
 135         if ((sym_storage = bfd_get_symtab_upper_bound(disasm_bfd)) >= 0) {
 136
 137             if (bfd_get_file_flags(disasm_bfd) & DYNAMIC) {
 138                 dyn_storage = bfd_get_dynamic_symtab_upper_bound(disasm_bfd);
 139 #  if defined(__alpha__)
 140                 /* XXX */
 141                 if (dyn_storage < 0)
 142                     dyn_storage = 0;
 143 #  else
 144                 assert(dyn_storage >= 0);
 145 #  endif
 146             }
 147             else
 148                 dyn_storage = 0;
 149
 150             jit_alloc((jit_pointer_t *)&disasm_symbols,
 151                       (sym_storage + dyn_storage) * sizeof(asymbol *));
 152             sym_count = bfd_canonicalize_symtab(disasm_bfd, disasm_symbols);
 153             assert(sym_count >= 0);
 154             if (dyn_storage) {
 155                 dyn_count = bfd_canonicalize_dynamic_symtab(disasm_bfd,
 156                                                             disasm_symbols +
 157                                                             sym_count);
 158                 assert(dyn_count >= 0);
 159             }
 160             else
 161                 dyn_count = 0;
 162             disasm_num_symbols = sym_count + dyn_count;
 163
 164             disasm_num_synthetic = bfd_get_synthetic_symtab(disasm_bfd,
 165                                                             sym_count,
 166                                                             disasm_symbols,
 167                                                             dyn_count,
 168                                                             disasm_symbols +
 169                                                             sym_count,
 170                                                             &disasm_synthetic);
 171             if (disasm_num_synthetic > 0) {
 172                 jit_realloc((jit_pointer_t *)&disasm_symbols,
 173                             (sym_storage + dyn_storage) * sizeof(asymbol *),
 174                             (sym_storage + dyn_storage + disasm_num_synthetic) *
 175                             sizeof(asymbol *));
 176                 for (offset = 0; offset < disasm_num_synthetic; offset++)
 177                     disasm_symbols[disasm_num_symbols++] =
 178                         disasm_synthetic + offset;
 179             }
 180
 181             /* remove symbols not useful for disassemble */
 182             in = out = disasm_symbols;
 183             for (offset = 0; offset < disasm_num_symbols; offset++) {
 184                 symbol = *in++;
 185                 if (symbol->name &&
 186                     symbol->name[0] != '\0' &&
 187                     !(symbol->flags & (BSF_DEBUGGING | BSF_SECTION_SYM)) &&
 188                     !bfd_is_und_section(symbol->section) &&
 189                     !bfd_is_com_section(symbol->section))
 190                     *out++ = symbol;
 191             }
 192             disasm_num_symbols = out - disasm_symbols;
 193             qsort(disasm_symbols, disasm_num_symbols,
 194                   sizeof(asymbol *), disasm_compare_symbols);
 195         }
 196     }
 197 #endif
 198 }
 199
 200 void
 201 jit_finish_debug(void)
 202 {
 203 #if DISASSEMBLER
 204     if (disasm_synthetic)
 205         jit_free((jit_pointer_t *)&disasm_synthetic);
 206     if (disasm_symbols)
 207         jit_free((jit_pointer_t *)&disasm_symbols);
 208     if (disasm_bfd)
 209         bfd_close (disasm_bfd);
 210 #endif
 211 }
 212
 213 void
 214 _jit_disassemble(jit_state_t *_jit)
 215 {
 216 #if DISASSEMBLER
 217     if (disasm_bfd) {
 218 #  if defined(__arm__)
 219         /* FIXME add mapping for prolog switching to arm and possible jump
 220          * before first prolog also in arm mode */
 221         disasm_info.disassembler_options = jit_cpu.thumb ? "force-thumb" : "";
 222 #  endif
 223
 224         disassemble(_jit->code.ptr, _jit->pc.uc - _jit->code.ptr);
 225     }
 226 #endif
 227 }
 228
 229 #if DISASSEMBLER
 230 /* Based on objdump source */
 231 static int
 232 disasm_compare_symbols(const void *ap, const void *bp)
 233 {
 234     const asymbol       *a = *(const asymbol **)ap;
 235     const asymbol       *b = *(const asymbol **)bp;
 236
 237     if (bfd_asymbol_value(a) > bfd_asymbol_value(b))
 238         return (1);
 239     if (bfd_asymbol_value(a) < bfd_asymbol_value(b))
 240         return (-1);
 241     return (0);
 242 }
 243
 244 #if __WORDSIZE == 32
 245 #  define address_buffer_length         16
 246 #  define address_buffer_format         "%llx"
 247 #else
 248 #  define address_buffer_length         32
 249 #  define address_buffer_format         "%lx"
 250 #endif
 251 static void
 252 disasm_print_address(bfd_vma addr, struct disassemble_info *info)
 253 {
 254     char                *name;
 255     char                *file;
 256     int                  line;
 257     char                 buffer[address_buffer_length];
 258
 259     sprintf(buffer, address_buffer_format, (long long)addr);
 260     (*info->fprintf_func)(info->stream, "0x%s", buffer);
 261
 262 #  define _jit                          disasm_jit
 263 #  undef jit_pointer_p
 264 #  define jit_pointer_p(u)                                      \
 265         ((u) >= _jit->code.ptr && (u) < _jit->pc.uc)
 266     if (jit_pointer_p((jit_uint8_t *)(jit_word_t)addr)) {
 267         if (jit_get_note((jit_uint8_t *)(jit_word_t)addr, &name, &file, &line))
 268             (*info->fprintf_func)(info->stream, " %s:%s:%d",
 269                                   name ? name : "",
 270                                   file ? file : "",
 271                                   line);
 272     }
 273 #  undef jit_pointer_p
 274 #  undef _jit
 275     else if (disasm_num_symbols) {
 276         long             low;
 277         long             high;
 278         long             offset;
 279         asymbol         *symbol;
 280
 281         low = 0;
 282         high = disasm_num_symbols;
 283         do {
 284             offset = (low + high) >> 1;
 285             symbol = disasm_symbols[offset];
 286             if (bfd_asymbol_value(symbol) > addr)
 287                 high = offset - 1;
 288             else if (bfd_asymbol_value(symbol) < addr)
 289                 low = offset + 1;
 290             else
 291                 break;
 292         } while (low < high);
 293
 294         if (offset >= 0 && offset < disasm_num_symbols) {
 295             if (bfd_asymbol_value(symbol) < addr) {
 296                 while (++offset < disasm_num_symbols) {
 297                     symbol = disasm_symbols[offset];
 298                     if (bfd_asymbol_value(symbol) >= addr)
 299                         break;
 300                 }
 301             }
 302             else if (bfd_asymbol_value(symbol) > addr) {
 303                 while (offset--) {
 304                     if (bfd_asymbol_value(disasm_symbols[offset]) < addr)
 305                         break;
 306                     symbol = disasm_symbols[offset];
 307                 }
 308             }
 309             if (bfd_asymbol_value(symbol) == addr)
 310                 (*info->fprintf_func)(info->stream, " # %s", symbol->name);
 311         }
 312     }
 313 }
 314
 315 static void
 316 _disassemble(jit_state_t *_jit, jit_pointer_t code, jit_int32_t length)
 317 {
 318     int                  bytes;
 319     char                *name, *old_name;
 320     char                *file, *old_file;
 321     int                  line,  old_line;
 322 #if __arm__
 323     jit_int32_t          offset;
 324     jit_bool_t           data_info;
 325     jit_int32_t          data_offset;
 326 #endif
 327     bfd_vma              pc = (jit_uword_t)code;
 328     bfd_vma              end = (jit_uword_t)code + length;
 329     char                 buffer[address_buffer_length];
 330 #if DEVEL_DISASSEMBLER
 331     jit_node_t          *node;
 332     jit_uword_t          prevw;
 333 #endif
 334
 335 #if __arm__
 336     data_info = _jitc && _jitc->data_info.ptr;
 337     data_offset = 0;
 338 #endif
 339     disasm_info.buffer = code;
 340     disasm_info.buffer_vma = (jit_uword_t)code;
 341     disasm_info.buffer_length = length;
 342     old_file = old_name = NULL;
 343     old_line = 0;
 344     disasm_jit = _jit;
 345 #if DEVEL_DISASSEMBLER
 346     node = _jitc->head;
 347     prevw = pc;
 348 #endif
 349     while (pc < end) {
 350 #if DEVEL_DISASSEMBLER
 351         while (node && (jit_uword_t)(prevw + node->offset) < (jit_uword_t)pc) {
 352             prevw += node->offset;
 353             node = node->next;
 354         }
 355         while (node && (jit_uword_t)(prevw + node->offset) == (jit_uword_t)pc) {
 356             jit_print_node(node);
 357             fputc('\n', stdout);
 358             prevw += node->offset;
 359             node = node->next;
 360         }
 361 #endif
 362 #if __arm__
 363     again:
 364         if (data_info) {
 365             while (_jitc->data_info.ptr[data_offset].code < pc) {
 366                 if (++data_offset >= _jitc->data_info.length) {
 367                     data_info = 0;
 368                     goto again;
 369                 }
 370             }
 371             if (pc == _jitc->data_info.ptr[data_offset].code) {
 372                 offset = _jitc->data_info.ptr[data_offset].length;
 373                 for (; offset >= 4; offset -= 4, pc += 4) {
 374                     bytes = sprintf(buffer, address_buffer_format, pc);
 375                     (*disasm_info.fprintf_func)(disasm_stream,
 376                                                 "%*c0x%s\t.data\t0x%08x\n",
 377                                                 16 - bytes, ' ', buffer,
 378                                                 *(jit_uint32_t *)
 379                                                 (jit_uint32_t)pc);
 380                 }
 381                 /* reset disassemble information instead of attempting
 382                  * to hack the arm specific backend data structures to
 383                  * tell it to forward the required number of bytes. */
 384                 disasm_info.buffer = (jit_pointer_t)(jit_uint32_t)pc;
 385                 disasm_info.buffer_vma = (jit_uword_t)pc;
 386                 if ((disasm_info.buffer_length = end - pc) <= 0)
 387                     break;
 388             }
 389         }
 390 #endif
 391         if (jit_get_note((jit_uint8_t *)(jit_word_t)pc, &name, &file, &line) &&
 392             (name != old_name || file != old_file || line != old_line)) {
 393             (*disasm_info.fprintf_func)(disasm_stream, "# %s:%s:%d\n",
 394                                         name ? name : "",
 395                                         file ? file : "",
 396                                         line);
 397             old_name = name;
 398             old_file = file;
 399             old_line = line;
 400         }
 401
 402         bytes = sprintf(buffer, address_buffer_format, (long long)pc);
 403         (*disasm_info.fprintf_func)(disasm_stream, "%*c0x%s\t",
 404                                     16 - bytes, ' ', buffer);
 405         pc += (*disasm_print)(pc, &disasm_info);
 406         putc('\n', disasm_stream);
 407     }
 408 }
 409 #endif