Re: [RFA/i386newframe] info cfi command

[Michael Snyder <msnyder@redhat.com>]

Michal Ludvig wrote:
> 
> Hi,
> this patch adds 'info cfi' command which is to be used for examining
> debug info. For now it only prints the instructions in a hex-form, but
> I'll make a resolver to nice strings later.
> 
> It doesn't change anything except that it adds a new command.
> 
> Can I commit it?
> 
> Michal Ludvig

May I request that the command be more self-documenting?
At the least, 'help' should tell you what a "CFI" is...



> --
> * SuSE CR, s.r.o     * mludvig@suse.cz
> * (+420) 296.545.373 * http://www.suse.cz
> 
>   -------------------------------------------------------------------------------
> 2003-05-29  Michal Ludvig  <mludvig@suse.cz>
> 
>         * dwarf-frame.c (cfi_info, _initialize_dwarf_frame): New
>         functions.
> 
> Index: dwarf-frame.c
> ===================================================================
> RCS file: /cvs/src/src/gdb/Attic/dwarf-frame.c,v
> retrieving revision 1.1.2.6
> diff -u -p -r1.1.2.6 dwarf-frame.c
> --- dwarf-frame.c       23 May 2003 20:18:32 -0000      1.1.2.6
> +++ dwarf-frame.c       29 May 2003 13:28:08 -0000
> @@ -32,6 +32,8 @@
>  #include "symtab.h"
>  #include "objfiles.h"
>  #include "regcache.h"
> +#include "gdbcmd.h"
> +#include "value.h"
> 
>  #include "gdb_assert.h"
>  #include <stddef.h>
> @@ -1232,4 +1234,83 @@ dwarf2_build_frame_info (struct objfile
>        while (frame_ptr < unit.dwarf_frame_buffer + unit.dwarf_frame_size)
>         frame_ptr = decode_frame_entry (&unit, frame_ptr, 0);
>      }
> +}
> +
> +/* Interactive interface.  */
> +
> +static void
> +cfi_info (char *arg, int from_tty)
> +{
> +  CORE_ADDR addr, low, high;
> +  unsigned long data_length;
> +  struct dwarf2_fde *fde;
> +  char *name;
> +  int i;
> +
> +  if (! arg)
> +    error_no_arg ("address");
> +
> +  addr = parse_and_eval_address (arg);
> +  printf_filtered ("Searching CFI for address %p...\n", (void*)addr);
> +
> +  if (find_pc_partial_function (addr, &name, &low, &high))
> +    printf_filtered ("\tBelongs to function '%s' (%p..%p).\n",
> +                    name, (void*)low, (void*)high);
> +
> +  fde = dwarf2_frame_find_fde (&addr);
> +  if (! fde)
> +  {
> +    printf_filtered ("\tCFI entry not found.\n");
> +    return;
> +  }
> +
> +  /* Print out CIE.  */
> +  data_length = fde->cie->end - fde->cie->initial_instructions;
> +  printf_filtered ("CIE:\n");
> +  printf_filtered ("\toffset = %llx\n"
> +                  "\tcode_align = %llu, data_align = %lld, ra_column = 0x%llx\n"
> +                  "\tdata_length = %lu, data: \n\t",
> +                  fde->cie->cie_pointer,
> +                  fde->cie->code_alignment_factor,
> +                  fde->cie->data_alignment_factor,
> +                  fde->cie->return_address_register,
> +                  data_length);
> +
> +  for (i = 0; i < data_length; i++)
> +  {
> +    printf_filtered ("0x%02x ", fde->cie->initial_instructions[i] & 0xff);
> +    if ((i + 1) % 8 == 0)
> +      printf_filtered ("\n\t");
> +    else if ((i + 1) % 4 == 0)
> +      printf_filtered ("  ");
> +  }
> +  if (i % 8)
> +    printf_filtered ("\n");
> +
> +  /* Print out FDE.  */
> +  data_length = fde->end - fde->instructions;
> +  printf_filtered ("FDE:\n");
> +  printf_filtered ("\tlocation = 0x%llx..0x%llx (size = %lld)\n"
> +                  "\tdata_length = %lu, data: \n\t",
> +                  fde->initial_location,
> +                  (fde->initial_location + fde->address_range),
> +                  fde->address_range, data_length);
> +  for (i = 0; i < data_length; i++)
> +  {
> +    printf_filtered ("0x%02x ", fde->instructions[i] & 0xff);
> +    if ((i + 1) % 8 == 0)
> +      printf_filtered ("\n%s", i + 1 < data_length ? "\t" : "");
> +    else if ((i + 1) % 4 == 0)
> +      printf_filtered ("  ");
> +  }
> +  if (i % 8)
> +    printf_filtered ("\n");
> +}
> +
> +void
> +_initialize_dwarf_frame (void)
> +{
> +  add_info ("cfi", cfi_info, "Find and print CFI for a given address.");
> +  add_info_alias ("fde", "cfi", 1);
> +  add_info_alias ("cie", "cfi", 1);
>  }