gdb/disasm.c

   1 /* Disassemble support for GDB.
   2
   3    Copyright 2000, 2001, 2002, 2003 Free Software Foundation, Inc.
   4
   5    This file is part of GDB.
   6
   7    This program is free software; you can redistribute it and/or modify
   8    it under the terms of the GNU General Public License as published by
   9    the Free Software Foundation; either version 2 of the License, or
  10    (at your option) any later version.
  11
  12    This program is distributed in the hope that it will be useful,
  13    but WITHOUT ANY WARRANTY; without even the implied warranty of
  14    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  15    GNU General Public License for more details.
  16
  17    You should have received a copy of the GNU General Public License
  18    along with this program; if not, write to the Free Software
  19    Foundation, Inc., 59 Temple Place - Suite 330,
  20    Boston, MA 02111-1307, USA.  */
  21
  22 #include "defs.h"
  23 #include "target.h"
  24 #include "value.h"
  25 #include "ui-out.h"
  26 #include "gdb_string.h"
  27 #include "disasm.h"
  28 #include "gdbcore.h"
  29
  30 /* Disassemble functions.
  31    FIXME: We should get rid of all the duplicate code in gdb that does
  32    the same thing: disassemble_command() and the gdbtk variation. */
  33
  34 /* This Structure is used to store line number information.
  35    We need a different sort of line table from the normal one cuz we can't
  36    depend upon implicit line-end pc's for lines to do the
  37    reordering in this function.  */
  38
  39 struct dis_line_entry
  40 {
  41   int line;
  42   CORE_ADDR start_pc;
  43   CORE_ADDR end_pc;
  44 };
  45
  46 /* Like target_read_memory, but slightly different parameters.  */
  47 static int
  48 dis_asm_read_memory (bfd_vma memaddr, bfd_byte *myaddr, unsigned int len,
  49                      disassemble_info *info)
  50 {
  51   return target_read_memory (memaddr, (char *) myaddr, len);
  52 }
  53
  54 /* Like memory_error with slightly different parameters.  */
  55 static void
  56 dis_asm_memory_error (int status, bfd_vma memaddr, disassemble_info *info)
  57 {
  58   memory_error (status, memaddr);
  59 }
  60
  61 /* Like print_address with slightly different parameters.  */
  62 static void
  63 dis_asm_print_address (bfd_vma addr, struct disassemble_info *info)
  64 {
  65   print_address (addr, info->stream);
  66 }
  67
  68 static int
  69 compare_lines (const void *mle1p, const void *mle2p)
  70 {
  71   struct dis_line_entry *mle1, *mle2;
  72   int val;
  73
  74   mle1 = (struct dis_line_entry *) mle1p;
  75   mle2 = (struct dis_line_entry *) mle2p;
  76
  77   val = mle1->line - mle2->line;
  78
  79   if (val != 0)
  80     return val;
  81
  82   return mle1->start_pc - mle2->start_pc;
  83 }
  84
  85 static int
  86 dump_insns (struct ui_out *uiout, disassemble_info * di,
  87             CORE_ADDR low, CORE_ADDR high,
  88             int how_many, struct ui_stream *stb)
  89 {
  90   int num_displayed = 0;
  91   CORE_ADDR pc;
  92
  93   /* parts of the symbolic representation of the address */
  94   int unmapped;
  95   int offset;
  96   int line;
  97   struct cleanup *ui_out_chain;
  98
  99   for (pc = low; pc < high;)
 100     {
 101       char *filename = NULL;
 102       char *name = NULL;
 103
 104       QUIT;
 105       if (how_many >= 0)
 106         {
 107           if (num_displayed >= how_many)
 108             break;
 109           else
 110             num_displayed++;
 111         }
 112       ui_out_chain = make_cleanup_ui_out_tuple_begin_end (uiout, NULL);
 113       ui_out_field_core_addr (uiout, "address", pc);
 114
 115       if (!build_address_symbolic (pc, 0, &name, &offset, &filename,
 116                                    &line, &unmapped))
 117         {
 118           /* We don't care now about line, filename and
 119              unmapped. But we might in the future. */
 120           ui_out_text (uiout, " <");
 121           ui_out_field_string (uiout, "func-name", name);
 122           ui_out_text (uiout, "+");
 123           ui_out_field_int (uiout, "offset", offset);
 124           ui_out_text (uiout, ">:\t");
 125         }
 126       else
 127         ui_out_text (uiout, ":\t");
 128
 129       if (filename != NULL)
 130         xfree (filename);
 131       if (name != NULL)
 132         xfree (name);
 133
 134       ui_file_rewind (stb->stream);
 135       pc += TARGET_PRINT_INSN (pc, di);
 136       ui_out_field_stream (uiout, "inst", stb);
 137       ui_file_rewind (stb->stream);
 138       do_cleanups (ui_out_chain);
 139       ui_out_text (uiout, "\n");
 140     }
 141   return num_displayed;
 142 }
 143
 144 /* The idea here is to present a source-O-centric view of a
 145    function to the user.  This means that things are presented
 146    in source order, with (possibly) out of order assembly
 147    immediately following.  */
 148 static void
 149 do_mixed_source_and_assembly (struct ui_out *uiout,
 150                               struct disassemble_info *di, int nlines,
 151                               struct linetable_entry *le,
 152                               CORE_ADDR low, CORE_ADDR high,
 153                               struct symtab *symtab,
 154                               int how_many, struct ui_stream *stb)
 155 {
 156   int newlines = 0;
 157   struct dis_line_entry *mle;
 158   struct symtab_and_line sal;
 159   int i;
 160   int out_of_order = 0;
 161   int next_line = 0;
 162   CORE_ADDR pc;
 163   int num_displayed = 0;
 164   struct cleanup *ui_out_chain;
 165
 166   mle = (struct dis_line_entry *) alloca (nlines
 167                                           * sizeof (struct dis_line_entry));
 168
 169   /* Copy linetable entries for this function into our data
 170      structure, creating end_pc's and setting out_of_order as
 171      appropriate.  */
 172
 173   /* First, skip all the preceding functions.  */
 174
 175   for (i = 0; i < nlines - 1 && le[i].pc < low; i++);
 176
 177   /* Now, copy all entries before the end of this function.  */
 178
 179   for (; i < nlines - 1 && le[i].pc < high; i++)
 180     {
 181       if (le[i].line == le[i + 1].line && le[i].pc == le[i + 1].pc)
 182         continue;               /* Ignore duplicates */
 183
 184       /* Skip any end-of-function markers.  */
 185       if (le[i].line == 0)
 186         continue;
 187
 188       mle[newlines].line = le[i].line;
 189       if (le[i].line > le[i + 1].line)
 190         out_of_order = 1;
 191       mle[newlines].start_pc = le[i].pc;
 192       mle[newlines].end_pc = le[i + 1].pc;
 193       newlines++;
 194     }
 195
 196   /* If we're on the last line, and it's part of the function,
 197      then we need to get the end pc in a special way.  */
 198
 199   if (i == nlines - 1 && le[i].pc < high)
 200     {
 201       mle[newlines].line = le[i].line;
 202       mle[newlines].start_pc = le[i].pc;
 203       sal = find_pc_line (le[i].pc, 0);
 204       mle[newlines].end_pc = sal.end;
 205       newlines++;
 206     }
 207
 208   /* Now, sort mle by line #s (and, then by addresses within
 209      lines). */
 210
 211   if (out_of_order)
 212     qsort (mle, newlines, sizeof (struct dis_line_entry), compare_lines);
 213
 214   /* Now, for each line entry, emit the specified lines (unless
 215      they have been emitted before), followed by the assembly code
 216      for that line.  */
 217
 218   ui_out_chain = make_cleanup_ui_out_list_begin_end (uiout, "asm_insns");
 219
 220   for (i = 0; i < newlines; i++)
 221     {
 222       struct cleanup *ui_out_tuple_chain = NULL;
 223       struct cleanup *ui_out_list_chain = NULL;
 224       int close_list = 1;
 225
 226       /* Print out everything from next_line to the current line.  */
 227       if (mle[i].line >= next_line)
 228         {
 229           if (next_line != 0)
 230             {
 231               /* Just one line to print. */
 232               if (next_line == mle[i].line)
 233                 {
 234                   ui_out_tuple_chain
 235                     = make_cleanup_ui_out_tuple_begin_end (uiout,
 236                                                            "src_and_asm_line");
 237                   print_source_lines (symtab, next_line, mle[i].line + 1, 0);
 238                 }
 239               else
 240                 {
 241                   /* Several source lines w/o asm instructions associated. */
 242                   for (; next_line < mle[i].line; next_line++)
 243                     {
 244                       struct cleanup *ui_out_list_chain_line;
 245                       struct cleanup *ui_out_tuple_chain_line;
 246
 247                       ui_out_tuple_chain_line
 248                         = make_cleanup_ui_out_tuple_begin_end (uiout,
 249                                                                "src_and_asm_line");
 250                       print_source_lines (symtab, next_line, next_line + 1,
 251                                           0);
 252                       ui_out_list_chain_line
 253                         = make_cleanup_ui_out_list_begin_end (uiout,
 254                                                               "line_asm_insn");
 255                       do_cleanups (ui_out_list_chain_line);
 256                       do_cleanups (ui_out_tuple_chain_line);
 257                     }
 258                   /* Print the last line and leave list open for
 259                      asm instructions to be added. */
 260                   ui_out_tuple_chain
 261                     = make_cleanup_ui_out_tuple_begin_end (uiout,
 262                                                            "src_and_asm_line");
 263                   print_source_lines (symtab, next_line, mle[i].line + 1, 0);
 264                 }
 265             }
 266           else
 267             {
 268               ui_out_tuple_chain
 269                 = make_cleanup_ui_out_tuple_begin_end (uiout, "src_and_asm_line");
 270               print_source_lines (symtab, mle[i].line, mle[i].line + 1, 0);
 271             }
 272
 273           next_line = mle[i].line + 1;
 274           ui_out_list_chain
 275             = make_cleanup_ui_out_list_begin_end (uiout, "line_asm_insn");
 276           /* Don't close the list if the lines are not in order. */
 277           if (i < (newlines - 1) && mle[i + 1].line <= mle[i].line)
 278             close_list = 0;
 279         }
 280
 281       num_displayed += dump_insns (uiout, di, mle[i].start_pc, mle[i].end_pc,
 282                                    how_many, stb);
 283       if (close_list)
 284         {
 285           do_cleanups (ui_out_list_chain);
 286           do_cleanups (ui_out_tuple_chain);
 287           ui_out_text (uiout, "\n");
 288           close_list = 0;
 289         }
 290       if (how_many >= 0)
 291         if (num_displayed >= how_many)
 292           break;
 293     }
 294   do_cleanups (ui_out_chain);
 295 }
 296
 297
 298 static void
 299 do_assembly_only (struct ui_out *uiout, disassemble_info * di,
 300                   CORE_ADDR low, CORE_ADDR high,
 301                   int how_many, struct ui_stream *stb)
 302 {
 303   int num_displayed = 0;
 304   struct cleanup *ui_out_chain;
 305
 306   ui_out_chain = make_cleanup_ui_out_list_begin_end (uiout, "asm_insns");
 307
 308   num_displayed = dump_insns (uiout, di, low, high, how_many, stb);
 309
 310   do_cleanups (ui_out_chain);
 311 }
 312
 313 /* Initialize the disassemble info struct ready for the specified
 314    stream.  */
 315
 316 static int
 317 fprintf_disasm (void *stream, const char *format, ...)
 318 {
 319   va_list args;
 320   va_start (args, format);
 321   vfprintf_filtered (stream, format, args);
 322   va_end (args);
 323   /* Something non -ve.  */
 324   return 0;
 325 }
 326
 327 static disassemble_info
 328 gdb_disassemble_info (struct gdbarch *gdbarch, struct ui_file *file)
 329 {
 330   disassemble_info di;
 331   init_disassemble_info (&di, file, fprintf_disasm);
 332   di.flavour = bfd_target_unknown_flavour;
 333   di.memory_error_func = dis_asm_memory_error;
 334   di.print_address_func = dis_asm_print_address;
 335   /* NOTE: cagney/2003-04-28: The original code, from the old Insight
 336      disassembler had a local optomization here.  By default it would
 337      access the executable file, instead of the target memory (there
 338      was a growing list of exceptions though).  Unfortunatly, the
 339      heuristic was flawed.  Commands like "disassemble &variable"
 340      didn't work as they relied on the access going to the target.
 341      Further, it has been supperseeded by trust-read-only-sections
 342      (although that should be superseeded by target_trust..._p()).  */
 343   di.read_memory_func = dis_asm_read_memory;
 344   di.arch = gdbarch_bfd_arch_info (gdbarch)->arch;
 345   di.mach = gdbarch_bfd_arch_info (gdbarch)->mach;
 346   di.endian = gdbarch_byte_order (gdbarch);
 347   return di;
 348 }
 349
 350 void
 351 gdb_disassembly (struct ui_out *uiout,
 352                 char *file_string,
 353                 int line_num,
 354                 int mixed_source_and_assembly,
 355                 int how_many, CORE_ADDR low, CORE_ADDR high)
 356 {
 357   struct ui_stream *stb = ui_out_stream_new (uiout);
 358   struct cleanup *cleanups = make_cleanup_ui_out_stream_delete (stb);
 359   disassemble_info di = gdb_disassemble_info (current_gdbarch, stb->stream);
 360   /* To collect the instruction outputted from opcodes. */
 361   struct symtab *symtab = NULL;
 362   struct linetable_entry *le = NULL;
 363   int nlines = -1;
 364
 365   /* Assume symtab is valid for whole PC range */
 366   symtab = find_pc_symtab (low);
 367
 368   if (symtab != NULL && symtab->linetable != NULL)
 369     {
 370       /* Convert the linetable to a bunch of my_line_entry's.  */
 371       le = symtab->linetable->item;
 372       nlines = symtab->linetable->nitems;
 373     }
 374
 375   if (!mixed_source_and_assembly || nlines <= 0
 376       || symtab == NULL || symtab->linetable == NULL)
 377     do_assembly_only (uiout, &di, low, high, how_many, stb);
 378
 379   else if (mixed_source_and_assembly)
 380     do_mixed_source_and_assembly (uiout, &di, nlines, le, low,
 381                                   high, symtab, how_many, stb);
 382
 383   do_cleanups (cleanups);
 384   gdb_flush (gdb_stdout);
 385 }
 386
 387 /* Print the instruction at address MEMADDR in debugged memory,
 388    on STREAM.  Returns length of the instruction, in bytes.  */
 389
 390 int
 391 gdb_print_insn (CORE_ADDR memaddr, struct ui_file *stream)
 392 {
 393   disassemble_info di = gdb_disassemble_info (current_gdbarch, stream);
 394   return TARGET_PRINT_INSN (memaddr, &di);
 395 }
 396
 397 \f
 398 /* FIXME: cagney/2003-04-28: This global deprecated_tm_print_insn_info
 399    is going away.  */
 400 disassemble_info deprecated_tm_print_insn_info;
 401
 402 extern void _initialize_disasm (void);
 403
 404 void
 405 _initialize_disasm (void)
 406 {
 407   init_disassemble_info (&deprecated_tm_print_insn_info, gdb_stdout,
 408                          fprintf_disasm);
 409   deprecated_tm_print_insn_info.flavour = bfd_target_unknown_flavour;
 410   deprecated_tm_print_insn_info.read_memory_func = dis_asm_read_memory;
 411   deprecated_tm_print_insn_info.memory_error_func = dis_asm_memory_error;
 412   deprecated_tm_print_insn_info.print_address_func = dis_asm_print_address;
 413 }