gdb/tui/tui-disasm.c

   1 /* Disassembly display.
   2
   3    Copyright (C) 1998-2016 Free Software Foundation, Inc.
   4
   5    Contributed by Hewlett-Packard Company.
   6
   7    This file is part of GDB.
   8
   9    This program is free software; you can redistribute it and/or modify
  10    it under the terms of the GNU General Public License as published by
  11    the Free Software Foundation; either version 3 of the License, or
  12    (at your option) any later version.
  13
  14    This program is distributed in the hope that it will be useful,
  15    but WITHOUT ANY WARRANTY; without even the implied warranty of
  16    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  17    GNU General Public License for more details.
  18
  19    You should have received a copy of the GNU General Public License
  20    along with this program.  If not, see <http://www.gnu.org/licenses/>.  */
  21
  22 #include "defs.h"
  23 #include "arch-utils.h"
  24 #include "symtab.h"
  25 #include "breakpoint.h"
  26 #include "frame.h"
  27 #include "value.h"
  28 #include "source.h"
  29 #include "disasm.h"
  30 #include "tui/tui.h"
  31 #include "tui/tui-data.h"
  32 #include "tui/tui-win.h"
  33 #include "tui/tui-layout.h"
  34 #include "tui/tui-winsource.h"
  35 #include "tui/tui-stack.h"
  36 #include "tui/tui-file.h"
  37 #include "tui/tui-disasm.h"
  38 #include "progspace.h"
  39 #include "objfiles.h"
  40
  41 #include "gdb_curses.h"
  42
  43 struct tui_asm_line
  44 {
  45   CORE_ADDR addr;
  46   char *addr_string;
  47   char *insn;
  48 };
  49
  50 /* Function to set the disassembly window's content.
  51    Disassemble count lines starting at pc.
  52    Return address of the count'th instruction after pc.  */
  53 static CORE_ADDR
  54 tui_disassemble (struct gdbarch *gdbarch, struct tui_asm_line *asm_lines,
  55                  CORE_ADDR pc, int count)
  56 {
  57   struct ui_file *gdb_dis_out;
  58
  59   /* Now init the ui_file structure.  */
  60   gdb_dis_out = tui_sfileopen (256);
  61
  62   /* Now construct each line.  */
  63   for (; count > 0; count--, asm_lines++)
  64     {
  65       if (asm_lines->addr_string)
  66         xfree (asm_lines->addr_string);
  67       if (asm_lines->insn)
  68         xfree (asm_lines->insn);
  69
  70       print_address (gdbarch, pc, gdb_dis_out);
  71       asm_lines->addr = pc;
  72       asm_lines->addr_string = xstrdup (tui_file_get_strbuf (gdb_dis_out));
  73
  74       ui_file_rewind (gdb_dis_out);
  75
  76       pc = pc + gdb_print_insn (gdbarch, pc, gdb_dis_out, NULL);
  77
  78       asm_lines->insn = xstrdup (tui_file_get_strbuf (gdb_dis_out));
  79
  80       /* Reset the buffer to empty.  */
  81       ui_file_rewind (gdb_dis_out);
  82     }
  83   ui_file_delete (gdb_dis_out);
  84   return pc;
  85 }
  86
  87 /* Find the disassembly address that corresponds to FROM lines above
  88    or below the PC.  Variable sized instructions are taken into
  89    account by the algorithm.  */
  90 static CORE_ADDR
  91 tui_find_disassembly_address (struct gdbarch *gdbarch, CORE_ADDR pc, int from)
  92 {
  93   CORE_ADDR new_low;
  94   int max_lines;
  95   int i;
  96   struct tui_asm_line *asm_lines;
  97
  98   max_lines = (from > 0) ? from : - from;
  99   if (max_lines <= 1)
 100      return pc;
 101
 102   asm_lines = XALLOCAVEC (struct tui_asm_line, max_lines);
 103   memset (asm_lines, 0, sizeof (struct tui_asm_line) * max_lines);
 104
 105   new_low = pc;
 106   if (from > 0)
 107     {
 108       tui_disassemble (gdbarch, asm_lines, pc, max_lines);
 109       new_low = asm_lines[max_lines - 1].addr;
 110     }
 111   else
 112     {
 113       CORE_ADDR last_addr;
 114       int pos;
 115       struct bound_minimal_symbol msymbol;
 116
 117       /* Find backward an address which is a symbol and for which
 118          disassembling from that address will fill completely the
 119          window.  */
 120       pos = max_lines - 1;
 121       do {
 122          new_low -= 1 * max_lines;
 123          msymbol = lookup_minimal_symbol_by_pc_section (new_low, 0);
 124
 125          if (msymbol.minsym)
 126             new_low = BMSYMBOL_VALUE_ADDRESS (msymbol);
 127          else
 128             new_low += 1 * max_lines;
 129
 130          tui_disassemble (gdbarch, asm_lines, new_low, max_lines);
 131          last_addr = asm_lines[pos].addr;
 132       } while (last_addr > pc && msymbol.minsym);
 133
 134       /* Scan forward disassembling one instruction at a time until
 135          the last visible instruction of the window matches the pc.
 136          We keep the disassembled instructions in the 'lines' window
 137          and shift it downward (increasing its addresses).  */
 138       if (last_addr < pc)
 139         do
 140           {
 141             CORE_ADDR next_addr;
 142
 143             pos++;
 144             if (pos >= max_lines)
 145               pos = 0;
 146
 147             next_addr = tui_disassemble (gdbarch, &asm_lines[pos],
 148                                          last_addr, 1);
 149
 150             /* If there are some problems while disassembling exit.  */
 151             if (next_addr <= last_addr)
 152               break;
 153             last_addr = next_addr;
 154           } while (last_addr <= pc);
 155       pos++;
 156       if (pos >= max_lines)
 157          pos = 0;
 158       new_low = asm_lines[pos].addr;
 159     }
 160   for (i = 0; i < max_lines; i++)
 161     {
 162       xfree (asm_lines[i].addr_string);
 163       xfree (asm_lines[i].insn);
 164     }
 165   return new_low;
 166 }
 167
 168 /* Function to set the disassembly window's content.  */
 169 enum tui_status
 170 tui_set_disassem_content (struct gdbarch *gdbarch, CORE_ADDR pc)
 171 {
 172   enum tui_status ret = TUI_FAILURE;
 173   int i;
 174   int offset = TUI_DISASM_WIN->detail.source_info.horizontal_offset;
 175   int max_lines;
 176   CORE_ADDR cur_pc;
 177   struct tui_gen_win_info *locator = tui_locator_win_info_ptr ();
 178   int tab_len = tui_default_tab_len ();
 179   struct tui_asm_line *asm_lines;
 180   int insn_pos;
 181   int addr_size, max_size;
 182   char *line;
 183
 184   if (pc == 0)
 185     return TUI_FAILURE;
 186
 187   ret = tui_alloc_source_buffer (TUI_DISASM_WIN);
 188   if (ret != TUI_SUCCESS)
 189     return ret;
 190
 191   TUI_DISASM_WIN->detail.source_info.gdbarch = gdbarch;
 192   TUI_DISASM_WIN->detail.source_info.start_line_or_addr.loa = LOA_ADDRESS;
 193   TUI_DISASM_WIN->detail.source_info.start_line_or_addr.u.addr = pc;
 194   cur_pc = locator->content[0]->which_element.locator.addr;
 195
 196   max_lines = TUI_DISASM_WIN->generic.height - 2;       /* Account for
 197                                                            hilite.  */
 198
 199   /* Get temporary table that will hold all strings (addr & insn).  */
 200   asm_lines = XALLOCAVEC (struct tui_asm_line, max_lines);
 201   memset (asm_lines, 0, sizeof (struct tui_asm_line) * max_lines);
 202
 203   tui_disassemble (gdbarch, asm_lines, pc, max_lines);
 204
 205   /* See what is the maximum length of an address and of a line.  */
 206   addr_size = 0;
 207   max_size = 0;
 208   for (i = 0; i < max_lines; i++)
 209     {
 210       size_t len = strlen (asm_lines[i].addr_string);
 211
 212       if (len > addr_size)
 213         addr_size = len;
 214
 215       len = strlen (asm_lines[i].insn) + tab_len;
 216       if (len > max_size)
 217         max_size = len;
 218     }
 219   max_size += addr_size + tab_len;
 220
 221   /* Allocate memory to create each line.  */
 222   line = (char*) alloca (max_size);
 223   insn_pos = (1 + (addr_size / tab_len)) * tab_len;
 224
 225   /* Now construct each line.  */
 226   for (i = 0; i < max_lines; i++)
 227     {
 228       struct tui_win_element *element;
 229       struct tui_source_element *src;
 230       int cur_len;
 231
 232       element = TUI_DISASM_WIN->generic.content[i];
 233       src = &element->which_element.source;
 234       strcpy (line, asm_lines[i].addr_string);
 235       cur_len = strlen (line);
 236
 237       /* Add spaces to make the instructions start on the same
 238          column.  */
 239       while (cur_len < insn_pos)
 240         {
 241           strcat (line, " ");
 242           cur_len++;
 243         }
 244
 245       strcat (line, asm_lines[i].insn);
 246
 247       /* Now copy the line taking the offset into account.  */
 248       if (strlen (line) > offset)
 249         strcpy (src->line, &line[offset]);
 250       else
 251         src->line[0] = '\0';
 252
 253       src->line_or_addr.loa = LOA_ADDRESS;
 254       src->line_or_addr.u.addr = asm_lines[i].addr;
 255       src->is_exec_point = asm_lines[i].addr == cur_pc;
 256
 257       /* See whether there is a breakpoint installed.  */
 258       src->has_break = (!src->is_exec_point
 259                         && breakpoint_here_p (current_program_space->aspace,
 260                                               pc)
 261                         != no_breakpoint_here);
 262
 263       xfree (asm_lines[i].addr_string);
 264       xfree (asm_lines[i].insn);
 265     }
 266   TUI_DISASM_WIN->generic.content_size = i;
 267   return TUI_SUCCESS;
 268 }
 269
 270
 271 /* Function to display the disassembly window with disassembled code.  */
 272 void
 273 tui_show_disassem (struct gdbarch *gdbarch, CORE_ADDR start_addr)
 274 {
 275   struct symtab *s = find_pc_line_symtab (start_addr);
 276   struct tui_win_info *win_with_focus = tui_win_with_focus ();
 277   struct tui_line_or_address val;
 278
 279   val.loa = LOA_ADDRESS;
 280   val.u.addr = start_addr;
 281   tui_add_win_to_layout (DISASSEM_WIN);
 282   tui_update_source_window (TUI_DISASM_WIN, gdbarch, s, val, FALSE);
 283
 284   /* If the focus was in the src win, put it in the asm win, if the
 285      source view isn't split.  */
 286   if (tui_current_layout () != SRC_DISASSEM_COMMAND
 287       && win_with_focus == TUI_SRC_WIN)
 288     tui_set_win_focus_to (TUI_DISASM_WIN);
 289
 290   return;
 291 }
 292
 293
 294 /* Function to display the disassembly window.  */
 295 void
 296 tui_show_disassem_and_update_source (struct gdbarch *gdbarch,
 297                                      CORE_ADDR start_addr)
 298 {
 299   struct symtab_and_line sal;
 300
 301   tui_show_disassem (gdbarch, start_addr);
 302   if (tui_current_layout () == SRC_DISASSEM_COMMAND)
 303     {
 304       struct tui_line_or_address val;
 305
 306       /* Update what is in the source window if it is displayed too,
 307          note that it follows what is in the disassembly window and
 308          visa-versa.  */
 309       sal = find_pc_line (start_addr, 0);
 310       val.loa = LOA_LINE;
 311       val.u.line_no = sal.line;
 312       tui_update_source_window (TUI_SRC_WIN, gdbarch, sal.symtab, val, TRUE);
 313       if (sal.symtab)
 314         {
 315           set_current_source_symtab_and_line (&sal);
 316           tui_update_locator_fullname (symtab_to_fullname (sal.symtab));
 317         }
 318       else
 319         tui_update_locator_fullname ("?");
 320     }
 321
 322   return;
 323 }
 324
 325 void
 326 tui_get_begin_asm_address (struct gdbarch **gdbarch_p, CORE_ADDR *addr_p)
 327 {
 328   struct tui_gen_win_info *locator;
 329   struct tui_locator_element *element;
 330   struct gdbarch *gdbarch = get_current_arch ();
 331   CORE_ADDR addr;
 332
 333   locator = tui_locator_win_info_ptr ();
 334   element = &locator->content[0]->which_element.locator;
 335
 336   if (element->addr == 0)
 337     {
 338       struct bound_minimal_symbol main_symbol;
 339
 340       /* Find address of the start of program.
 341          Note: this should be language specific.  */
 342       main_symbol = lookup_minimal_symbol ("main", NULL, NULL);
 343       if (main_symbol.minsym == 0)
 344         main_symbol = lookup_minimal_symbol ("MAIN", NULL, NULL);
 345       if (main_symbol.minsym == 0)
 346         main_symbol = lookup_minimal_symbol ("_start", NULL, NULL);
 347       if (main_symbol.minsym)
 348         addr = BMSYMBOL_VALUE_ADDRESS (main_symbol);
 349       else
 350         addr = 0;
 351     }
 352   else                          /* The target is executing.  */
 353     {
 354       gdbarch = element->gdbarch;
 355       addr = element->addr;
 356     }
 357
 358   *gdbarch_p = gdbarch;
 359   *addr_p = addr;
 360 }
 361
 362 /* Determine what the low address will be to display in the TUI's
 363    disassembly window.  This may or may not be the same as the low
 364    address input.  */
 365 CORE_ADDR
 366 tui_get_low_disassembly_address (struct gdbarch *gdbarch,
 367                                  CORE_ADDR low, CORE_ADDR pc)
 368 {
 369   int pos;
 370
 371   /* Determine where to start the disassembly so that the pc is about
 372      in the middle of the viewport.  */
 373   pos = tui_default_win_viewport_height (DISASSEM_WIN, DISASSEM_COMMAND) / 2;
 374   pc = tui_find_disassembly_address (gdbarch, pc, -pos);
 375
 376   if (pc < low)
 377     pc = low;
 378   return pc;
 379 }
 380
 381 /* Scroll the disassembly forward or backward vertically.  */
 382 void
 383 tui_vertical_disassem_scroll (enum tui_scroll_direction scroll_direction,
 384                               int num_to_scroll)
 385 {
 386   if (TUI_DISASM_WIN->generic.content != NULL)
 387     {
 388       struct gdbarch *gdbarch = TUI_DISASM_WIN->detail.source_info.gdbarch;
 389       CORE_ADDR pc;
 390       tui_win_content content;
 391       struct tui_line_or_address val;
 392       int dir;
 393
 394       content = (tui_win_content) TUI_DISASM_WIN->generic.content;
 395
 396       pc = content[0]->which_element.source.line_or_addr.u.addr;
 397       num_to_scroll++;
 398       dir = (scroll_direction == FORWARD_SCROLL)
 399         ? num_to_scroll : -num_to_scroll;
 400
 401       val.loa = LOA_ADDRESS;
 402       val.u.addr = tui_find_disassembly_address (gdbarch, pc, dir);
 403       tui_update_source_window_as_is (TUI_DISASM_WIN, gdbarch,
 404                                       NULL, val, FALSE);
 405     }
 406 }