Subversion Repositories openrisc_2011-10-31

/* Disassemble support for GDB.

   Copyright (C) 2000, 2001, 2002, 2003, 2004, 2005, 2007, 2008

   Free Software Foundation, Inc.

   This file is part of GDB.

   This program is free software; you can redistribute it and/or modify

   it under the terms of the GNU General Public License as published by

   the Free Software Foundation; either version 3 of the License, or

   (at your option) any later version.

   This program is distributed in the hope that it will be useful,

   but WITHOUT ANY WARRANTY; without even the implied warranty of

   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the

   GNU General Public License for more details.

   You should have received a copy of the GNU General Public License

   along with this program.  If not, see <http://www.gnu.org/licenses/>.  */

#include "defs.h"

#include "target.h"

#include "value.h"

#include "ui-out.h"

#include "gdb_string.h"

#include "disasm.h"

#include "gdbcore.h"

#include "dis-asm.h"

/* Disassemble functions.

   FIXME: We should get rid of all the duplicate code in gdb that does

   the same thing: disassemble_command() and the gdbtk variation. */

/* This Structure is used to store line number information.

   We need a different sort of line table from the normal one cuz we can't

   depend upon implicit line-end pc's for lines to do the

   reordering in this function.  */

struct dis_line_entry

{

  int line;

  CORE_ADDR start_pc;

  CORE_ADDR end_pc;

};

/* Like target_read_memory, but slightly different parameters.  */

static int

dis_asm_read_memory (bfd_vma memaddr, gdb_byte *myaddr, unsigned int len,

                     struct disassemble_info *info)

{

  return target_read_memory (memaddr, myaddr, len);

}

/* Like memory_error with slightly different parameters.  */

static void

dis_asm_memory_error (int status, bfd_vma memaddr,

                      struct disassemble_info *info)

{

  memory_error (status, memaddr);

}

/* Like print_address with slightly different parameters.  */

static void

dis_asm_print_address (bfd_vma addr, struct disassemble_info *info)

{

  print_address (addr, info->stream);

}

static int

compare_lines (const void *mle1p, const void *mle2p)

{

  struct dis_line_entry *mle1, *mle2;

  int val;

  mle1 = (struct dis_line_entry *) mle1p;

  mle2 = (struct dis_line_entry *) mle2p;

  val = mle1->line - mle2->line;

  if (val != 0)

    return val;

  return mle1->start_pc - mle2->start_pc;

}

static int

dump_insns (struct ui_out *uiout, struct disassemble_info * di,

            CORE_ADDR low, CORE_ADDR high,

            int how_many, struct ui_stream *stb)

{

  int num_displayed = 0;

  CORE_ADDR pc;

  /* parts of the symbolic representation of the address */

  int unmapped;

  int offset;

  int line;

  struct cleanup *ui_out_chain;

  for (pc = low; pc < high;)

    {

      char *filename = NULL;

      char *name = NULL;

      QUIT;

      if (how_many >= 0)

        {

          if (num_displayed >= how_many)

            break;

          else

            num_displayed++;

        }

      ui_out_chain = make_cleanup_ui_out_tuple_begin_end (uiout, NULL);

      ui_out_field_core_addr (uiout, "address", pc);

      if (!build_address_symbolic (pc, 0, &name, &offset, &filename,

                                   &line, &unmapped))

        {

          /* We don't care now about line, filename and

             unmapped. But we might in the future. */

          ui_out_text (uiout, " <");

          ui_out_field_string (uiout, "func-name", name);

          ui_out_text (uiout, "+");

          ui_out_field_int (uiout, "offset", offset);

          ui_out_text (uiout, ">:\t");

        }

      else

        ui_out_text (uiout, ":\t");

      if (filename != NULL)

        xfree (filename);

      if (name != NULL)

        xfree (name);

      ui_file_rewind (stb->stream);

      pc += gdbarch_print_insn (current_gdbarch, pc, di);

      ui_out_field_stream (uiout, "inst", stb);

      ui_file_rewind (stb->stream);

      do_cleanups (ui_out_chain);

      ui_out_text (uiout, "\n");

    }

  return num_displayed;

}

/* The idea here is to present a source-O-centric view of a

   function to the user.  This means that things are presented

   in source order, with (possibly) out of order assembly

   immediately following.  */

static void

do_mixed_source_and_assembly (struct ui_out *uiout,

                              struct disassemble_info *di, int nlines,

                              struct linetable_entry *le,

                              CORE_ADDR low, CORE_ADDR high,

                              struct symtab *symtab,

                              int how_many, struct ui_stream *stb)

{

  int newlines = 0;

  struct dis_line_entry *mle;

  struct symtab_and_line sal;

  int i;

  int out_of_order = 0;

  int next_line = 0;

  CORE_ADDR pc;

  int num_displayed = 0;

  struct cleanup *ui_out_chain;

  struct cleanup *ui_out_tuple_chain = make_cleanup (null_cleanup, 0);

  struct cleanup *ui_out_list_chain = make_cleanup (null_cleanup, 0);

  mle = (struct dis_line_entry *) alloca (nlines

                                          * sizeof (struct dis_line_entry));

  /* Copy linetable entries for this function into our data

     structure, creating end_pc's and setting out_of_order as

     appropriate.  */

  /* First, skip all the preceding functions.  */

  for (i = 0; i < nlines - 1 && le[i].pc < low; i++);

  /* Now, copy all entries before the end of this function.  */

  for (; i < nlines - 1 && le[i].pc < high; i++)

    {

      if (le[i].line == le[i + 1].line && le[i].pc == le[i + 1].pc)

        continue;               /* Ignore duplicates */

      /* Skip any end-of-function markers.  */

      if (le[i].line == 0)

        continue;

      mle[newlines].line = le[i].line;

      if (le[i].line > le[i + 1].line)

        out_of_order = 1;

      mle[newlines].start_pc = le[i].pc;

      mle[newlines].end_pc = le[i + 1].pc;

      newlines++;

    }

  /* If we're on the last line, and it's part of the function,

     then we need to get the end pc in a special way.  */

  if (i == nlines - 1 && le[i].pc < high)

    {

      mle[newlines].line = le[i].line;

      mle[newlines].start_pc = le[i].pc;

      sal = find_pc_line (le[i].pc, 0);

      mle[newlines].end_pc = sal.end;

      newlines++;

    }

  /* Now, sort mle by line #s (and, then by addresses within

     lines). */

  if (out_of_order)

    qsort (mle, newlines, sizeof (struct dis_line_entry), compare_lines);

  /* Now, for each line entry, emit the specified lines (unless

     they have been emitted before), followed by the assembly code

     for that line.  */

  ui_out_chain = make_cleanup_ui_out_list_begin_end (uiout, "asm_insns");

  for (i = 0; i < newlines; i++)

    {

      /* Print out everything from next_line to the current line.  */

      if (mle[i].line >= next_line)

        {

          if (next_line != 0)

            {

              /* Just one line to print. */

              if (next_line == mle[i].line)

                {

                  ui_out_tuple_chain

                    = make_cleanup_ui_out_tuple_begin_end (uiout,

                                                           "src_and_asm_line");

                  print_source_lines (symtab, next_line, mle[i].line + 1, 0);

                }

              else

                {

                  /* Several source lines w/o asm instructions associated. */

                  for (; next_line < mle[i].line; next_line++)

                    {

                      struct cleanup *ui_out_list_chain_line;

                      struct cleanup *ui_out_tuple_chain_line;

                      ui_out_tuple_chain_line

                        = make_cleanup_ui_out_tuple_begin_end (uiout,

                                                               "src_and_asm_line");

                      print_source_lines (symtab, next_line, next_line + 1,

                                          0);

                      ui_out_list_chain_line

                        = make_cleanup_ui_out_list_begin_end (uiout,

                                                              "line_asm_insn");

                      do_cleanups (ui_out_list_chain_line);

                      do_cleanups (ui_out_tuple_chain_line);

                    }

                  /* Print the last line and leave list open for

                     asm instructions to be added. */

                  ui_out_tuple_chain

                    = make_cleanup_ui_out_tuple_begin_end (uiout,

                                                           "src_and_asm_line");

                  print_source_lines (symtab, next_line, mle[i].line + 1, 0);

                }

            }

          else

            {

              ui_out_tuple_chain

                = make_cleanup_ui_out_tuple_begin_end (uiout, "src_and_asm_line");

              print_source_lines (symtab, mle[i].line, mle[i].line + 1, 0);

            }

          next_line = mle[i].line + 1;

          ui_out_list_chain

            = make_cleanup_ui_out_list_begin_end (uiout, "line_asm_insn");

        }

      num_displayed += dump_insns (uiout, di, mle[i].start_pc, mle[i].end_pc,

                                   how_many, stb);

      /* When we've reached the end of the mle array, or we've seen the last

         assembly range for this source line, close out the list/tuple.  */

      if (i == (newlines - 1) || mle[i + 1].line > mle[i].line)

        {

          do_cleanups (ui_out_list_chain);

          do_cleanups (ui_out_tuple_chain);

          ui_out_tuple_chain = make_cleanup (null_cleanup, 0);

          ui_out_list_chain = make_cleanup (null_cleanup, 0);

          ui_out_text (uiout, "\n");

        }

      if (how_many >= 0 && num_displayed >= how_many)

        break;

    }

  do_cleanups (ui_out_chain);

}

static void

do_assembly_only (struct ui_out *uiout, struct disassemble_info * di,

                  CORE_ADDR low, CORE_ADDR high,

                  int how_many, struct ui_stream *stb)

{

  int num_displayed = 0;

  struct cleanup *ui_out_chain;

  ui_out_chain = make_cleanup_ui_out_list_begin_end (uiout, "asm_insns");

  num_displayed = dump_insns (uiout, di, low, high, how_many, stb);

  do_cleanups (ui_out_chain);

}

/* Initialize the disassemble info struct ready for the specified

   stream.  */

static int ATTR_FORMAT (printf, 2, 3)

fprintf_disasm (void *stream, const char *format, ...)

{

  va_list args;

  va_start (args, format);

  vfprintf_filtered (stream, format, args);

  va_end (args);

  /* Something non -ve.  */

  return 0;

}

static struct disassemble_info

gdb_disassemble_info (struct gdbarch *gdbarch, struct ui_file *file)

{

  struct disassemble_info di;

  init_disassemble_info (&di, file, fprintf_disasm);

  di.flavour = bfd_target_unknown_flavour;

  di.memory_error_func = dis_asm_memory_error;

  di.print_address_func = dis_asm_print_address;

  /* NOTE: cagney/2003-04-28: The original code, from the old Insight

     disassembler had a local optomization here.  By default it would

     access the executable file, instead of the target memory (there

     was a growing list of exceptions though).  Unfortunately, the

     heuristic was flawed.  Commands like "disassemble &variable"

     didn't work as they relied on the access going to the target.

     Further, it has been supperseeded by trust-read-only-sections

     (although that should be superseeded by target_trust..._p()).  */

  di.read_memory_func = dis_asm_read_memory;

  di.arch = gdbarch_bfd_arch_info (gdbarch)->arch;

  di.mach = gdbarch_bfd_arch_info (gdbarch)->mach;

  di.endian = gdbarch_byte_order (gdbarch);

  disassemble_init_for_target (&di);

  return di;

}

void

gdb_disassembly (struct ui_out *uiout,

                char *file_string,

                int line_num,

                int mixed_source_and_assembly,

                int how_many, CORE_ADDR low, CORE_ADDR high)

{

  struct ui_stream *stb = ui_out_stream_new (uiout);

  struct cleanup *cleanups = make_cleanup_ui_out_stream_delete (stb);

  struct disassemble_info di = gdb_disassemble_info (current_gdbarch, stb->stream);

  /* To collect the instruction outputted from opcodes. */

  struct symtab *symtab = NULL;

  struct linetable_entry *le = NULL;

  int nlines = -1;

  /* Assume symtab is valid for whole PC range */

  symtab = find_pc_symtab (low);

  if (symtab != NULL && symtab->linetable != NULL)

    {

      /* Convert the linetable to a bunch of my_line_entry's.  */

      le = symtab->linetable->item;

      nlines = symtab->linetable->nitems;

    }

  if (!mixed_source_and_assembly || nlines <= 0

      || symtab == NULL || symtab->linetable == NULL)

    do_assembly_only (uiout, &di, low, high, how_many, stb);

  else if (mixed_source_and_assembly)

    do_mixed_source_and_assembly (uiout, &di, nlines, le, low,

                                  high, symtab, how_many, stb);

  do_cleanups (cleanups);

  gdb_flush (gdb_stdout);

}

/* Print the instruction at address MEMADDR in debugged memory,

   on STREAM.  Returns the length of the instruction, in bytes,

   and, if requested, the number of branch delay slot instructions.  */

int

gdb_print_insn (CORE_ADDR memaddr, struct ui_file *stream,

                int *branch_delay_insns)

{

  struct disassemble_info di;

  int length;

  di = gdb_disassemble_info (current_gdbarch, stream);

  length = gdbarch_print_insn (current_gdbarch, memaddr, &di);

  if (branch_delay_insns)

    {

      if (di.insn_info_valid)

        *branch_delay_insns = di.branch_delay_insns;

      else

        *branch_delay_insns = 0;

    }

  return length;

}