[commited][PATCH 1/3] [gdb/symtab] Factor out elf_symfile_read_dwarf2

[Tom de Vries <tdevries@suse.de>]

On 9/22/22 17:20, Tom de Vries via Gdb-patches wrote:
> Factor out elf_symfile_read_dwarf2 from elf_symfile_read.  NFC.
> 
> Tested on x86_64-linux.

Committed.

Thanks,
- Tom

> ---
>   gdb/elfread.c | 142 +++++++++++++++++++++++++++-----------------------
>   1 file changed, 78 insertions(+), 64 deletions(-)
> 
> diff --git a/gdb/elfread.c b/gdb/elfread.c
> index 8aee634b44b..ed11c67dc02 100644
> --- a/gdb/elfread.c
> +++ b/gdb/elfread.c
> @@ -1166,6 +1166,83 @@ elf_read_minimal_symbols (struct objfile *objfile, int symfile_flags,
>     symtab_create_debug_printf ("done reading minimal symbols");
>   }
>   
> +/* Dwarf-specific helper for elf_symfile_read.  Return true if we managed to
> +   load dwarf debug info.  */
> +
> +static bool
> +elf_symfile_read_dwarf2 (struct objfile *objfile,
> +			 symfile_add_flags symfile_flags)
> +{
> +  bool has_dwarf2 = true;
> +
> +  if (dwarf2_has_info (objfile, NULL, true))
> +    dwarf2_initialize_objfile (objfile);
> +  /* If the file has its own symbol tables it has no separate debug
> +     info.  `.dynsym'/`.symtab' go to MSYMBOLS, `.debug_info' goes to
> +     SYMTABS/PSYMTABS.	`.gnu_debuglink' may no longer be present with
> +     `.note.gnu.build-id'.
> +
> +     .gnu_debugdata is !objfile::has_partial_symbols because it contains only
> +     .symtab, not .debug_* section.  But if we already added .gnu_debugdata as
> +     an objfile via find_separate_debug_file_in_section there was no separate
> +     debug info available.  Therefore do not attempt to search for another one,
> +     objfile->separate_debug_objfile->separate_debug_objfile GDB guarantees to
> +     be NULL and we would possibly violate it.	*/
> +
> +  else if (!objfile->has_partial_symbols ()
> +	   && objfile->separate_debug_objfile == NULL
> +	   && objfile->separate_debug_objfile_backlink == NULL)
> +    {
> +      std::string debugfile = find_separate_debug_file_by_buildid (objfile);
> +
> +      if (debugfile.empty ())
> +	debugfile = find_separate_debug_file_by_debuglink (objfile);
> +
> +      if (!debugfile.empty ())
> +	{
> +	  gdb_bfd_ref_ptr debug_bfd (symfile_bfd_open (debugfile.c_str ()));
> +
> +	  symbol_file_add_separate (debug_bfd, debugfile.c_str (),
> +				    symfile_flags, objfile);
> +	}
> +      else
> +	{
> +	  has_dwarf2 = false;
> +	  const struct bfd_build_id *build_id
> +	    = build_id_bfd_get (objfile->obfd.get ());
> +	  const char *filename = bfd_get_filename (objfile->obfd.get ());
> +
> +	  if (build_id != nullptr)
> +	    {
> +	      gdb::unique_xmalloc_ptr<char> symfile_path;
> +	      scoped_fd fd (debuginfod_debuginfo_query (build_id->data,
> +							build_id->size,
> +							filename,
> +							&symfile_path));
> +
> +	      if (fd.get () >= 0)
> +		{
> +		  /* File successfully retrieved from server.  */
> +		  gdb_bfd_ref_ptr debug_bfd (symfile_bfd_open (symfile_path.get ()));
> +
> +		  if (debug_bfd == nullptr)
> +		    warning (_("File \"%s\" from debuginfod cannot be opened as bfd"),
> +			     filename);
> +		  else if (build_id_verify (debug_bfd.get (), build_id->size,
> +					    build_id->data))
> +		    {
> +		      symbol_file_add_separate (debug_bfd, symfile_path.get (),
> +						symfile_flags, objfile);
> +		      has_dwarf2 = true;
> +		    }
> +		}
> +	    }
> +	}
> +    }
> +
> +  return has_dwarf2;
> +}
> +
>   /* Scan and build partial symbols for a symbol file.
>      We have been initialized by a call to elf_symfile_init, which
>      currently does nothing.
> @@ -1195,7 +1272,6 @@ elf_symfile_read (struct objfile *objfile, symfile_add_flags symfile_flags)
>   {
>     bfd *abfd = objfile->obfd.get ();
>     struct elfinfo ei;
> -  bool has_dwarf2 = true;
>   
>     memset ((char *) &ei, 0, sizeof (ei));
>     if (!(objfile->flags & OBJF_READNEVER))
> @@ -1244,69 +1320,7 @@ elf_symfile_read (struct objfile *objfile, symfile_add_flags symfile_flags)
>   				bfd_section_size (str_sect));
>       }
>   
> -  if (dwarf2_has_info (objfile, NULL, true))
> -    dwarf2_initialize_objfile (objfile);
> -  /* If the file has its own symbol tables it has no separate debug
> -     info.  `.dynsym'/`.symtab' go to MSYMBOLS, `.debug_info' goes to
> -     SYMTABS/PSYMTABS.  `.gnu_debuglink' may no longer be present with
> -     `.note.gnu.build-id'.
> -
> -     .gnu_debugdata is !objfile::has_partial_symbols because it contains only
> -     .symtab, not .debug_* section.  But if we already added .gnu_debugdata as
> -     an objfile via find_separate_debug_file_in_section there was no separate
> -     debug info available.  Therefore do not attempt to search for another one,
> -     objfile->separate_debug_objfile->separate_debug_objfile GDB guarantees to
> -     be NULL and we would possibly violate it.  */
> -
> -  else if (!objfile->has_partial_symbols ()
> -	   && objfile->separate_debug_objfile == NULL
> -	   && objfile->separate_debug_objfile_backlink == NULL)
> -    {
> -      std::string debugfile = find_separate_debug_file_by_buildid (objfile);
> -
> -      if (debugfile.empty ())
> -	debugfile = find_separate_debug_file_by_debuglink (objfile);
> -
> -      if (!debugfile.empty ())
> -	{
> -	  gdb_bfd_ref_ptr debug_bfd (symfile_bfd_open (debugfile.c_str ()));
> -
> -	  symbol_file_add_separate (debug_bfd, debugfile.c_str (),
> -				    symfile_flags, objfile);
> -	}
> -      else
> -	{
> -	  has_dwarf2 = false;
> -	  const struct bfd_build_id *build_id
> -	    = build_id_bfd_get (objfile->obfd.get ());
> -	  const char *filename = bfd_get_filename (objfile->obfd.get ());
> -
> -	  if (build_id != nullptr)
> -	    {
> -	      gdb::unique_xmalloc_ptr<char> symfile_path;
> -	      scoped_fd fd (debuginfod_debuginfo_query (build_id->data,
> -							build_id->size,
> -							filename,
> -							&symfile_path));
> -
> -	      if (fd.get () >= 0)
> -		{
> -		  /* File successfully retrieved from server.  */
> -		  gdb_bfd_ref_ptr debug_bfd (symfile_bfd_open (symfile_path.get ()));
> -
> -		  if (debug_bfd == nullptr)
> -		    warning (_("File \"%s\" from debuginfod cannot be opened as bfd"),
> -			     filename);
> -		  else if (build_id_verify (debug_bfd.get (), build_id->size, build_id->data))
> -		    {
> -		      symbol_file_add_separate (debug_bfd, symfile_path.get (),
> -						symfile_flags, objfile);
> -		      has_dwarf2 = true;
> -		    }
> -		}
> -	    }
> -	}
> -    }
> +  bool has_dwarf2 = elf_symfile_read_dwarf2 (objfile, symfile_flags);
>   
>     /* Read the CTF section only if there is no DWARF info.  */
>     if (!has_dwarf2 && ei.ctfsect)
> 
> base-commit: aaf3f3f3bb38a59125ea34afa0ef7e0e14c2e916