Subversion Repositories openrisc_2011-10-31

/* Disassemble support for GDB.

   Copyright (C) 2000, 2001, 2002, 2003, 2004, 2005, 2007, 2008, 2009, 2010

   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)

{

  struct gdbarch *gdbarch = info->application_data;

  print_address (gdbarch, 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 gdbarch *gdbarch, struct ui_out *uiout,

            struct disassemble_info * di,

            CORE_ADDR low, CORE_ADDR high,

            int how_many, int flags, 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_text (uiout, pc_prefix (pc));

      ui_out_field_core_addr (uiout, "address", gdbarch, pc);

      if (!build_address_symbolic (gdbarch, 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, " <");

          if ((flags & DISASSEMBLY_OMIT_FNAME) == 0)

            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);

      if (flags & DISASSEMBLY_RAW_INSN)

        {

          CORE_ADDR old_pc = pc;

          bfd_byte data;

          int status;

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

          for (;old_pc < pc; old_pc++)

            {

              status = (*di->read_memory_func) (old_pc, &data, 1, di);

              if (status != 0)

                (*di->memory_error_func) (status, old_pc, di);

              ui_out_message (uiout, 0, " %02x", (unsigned)data);

            }

          ui_out_text (uiout, "\t");

        }

      else

        pc += gdbarch_print_insn (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 gdbarch *gdbarch, 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, int flags, 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 (gdbarch, uiout, di,

                                   mle[i].start_pc, mle[i].end_pc,

                                   how_many, flags, 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 gdbarch *gdbarch, struct ui_out *uiout,

                  struct disassemble_info * di,

                  CORE_ADDR low, CORE_ADDR high,

                  int how_many, int flags, 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 (gdbarch, uiout, di, low, high, how_many,

                              flags, 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);

  di.endian_code = gdbarch_byte_order_for_code (gdbarch);

  di.application_data = gdbarch;

  disassemble_init_for_target (&di);

  return di;

}

void

gdb_disassembly (struct gdbarch *gdbarch, struct ui_out *uiout,

                 char *file_string, int flags, 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 (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 (!(flags & DISASSEMBLY_SOURCE) || nlines <= 0

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

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

  else if (flags & DISASSEMBLY_SOURCE)

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

                                  high, symtab, how_many, flags, 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 (struct gdbarch *gdbarch, CORE_ADDR memaddr,

                struct ui_file *stream, int *branch_delay_insns)

{

  struct disassemble_info di;

  int length;

  di = gdb_disassemble_info (gdbarch, stream);

  length = gdbarch_print_insn (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;

}