This is the mail archive of the gdb-patches@sources.redhat.com mailing list for the GDB project.


Index Nav: [Date Index] [Subject Index] [Author Index] [Thread Index]
Message Nav: [Date Prev] [Date Next] [Thread Prev] [Thread Next]

Re: [PATCH] Start abstraction of C++ abi's


Elena Zannoni <ezannoni@cygnus.com> writes:

> Daniel Berlin writes:
>  > 
>  > This patch, plus the attached files, start the abstraction of the C++
>  > ABI's.
>  > 
>  > I've started by replacing the simple things, and will incrementally
>  > replace the more complex things, and the things that require real code
>  > changes, as time goes on.
>  > 
>  > The cp-abi directory, and it's files, are attached in a gzipped tar file.
>  > 
>  > This fixes some problems with the new-abi already, like not being able
>  > to set breakpoints on destructors (if you try it, you'll get:
>  > 
>  > (gdb) b foo::~foo
>  > the class `foo' does not have destructor defined
>  > Hint: try 'foo::~foo<TAB> or 'foo::~foo<ESC-?>
>  > (Note leading single quote.)
>  > (gdb)
>  > )
>  > 
>  > I haven't added the method for detecting which C++ abi we are using,
>  > so it simply defaults to the gnu v2 abi.
>  > 
>  > However, I have verified the gnu v3 abi parts work fine too (that's how i
>  > know it fixed breakpoints on destructors).
>  > 
>  > This stuff touches a lot of files, but it's only removing code, or
>  > changing a macro call to a function call (IE VTBL_PREFIX_P ->
>  > vtbl_prefix_p, DESTRUCTOR_PREFIX_P -> destructor_prefix_p).
>  > 
>  > Who exactly do i need approval from to check this stuff in?
>  > 
>  > As I said, this is an incremental process. This is the minimum number
>  > of changes necessary to start abstracting the simple things. There is
>  > no way to make this patch smaller, without breaking gdb.
>  > 
>  > 
>  > I need someone to look at the configure.in change, i'm not positive I
>  > did it right.
>  > 
>  > --Dan
>  > 
> 
> Dan, I don't see ChangeLogs entries in your patch.
I'll resend with the changelog entries, and the things you ask for
below fixed.


> Also one file in the cp-abi directory looks empty:
> 
> kwikemart.cygnus.com: 15 % tar tvf cp-abi.tar 
> -rw-r--r-- dberlin/users  2551 2001-02-18 15:12 cp-abi.h
> drwxr-xr-x dberlin/users     0 2001-02-18 15:45 cp-abi/
> -rw-r--r-- dberlin/users  1967 2001-02-18 15:39 cp-abi/gnu-v3-abi.c
> -rw-r--r-- dberlin/users     0 2001-02-18 15:37 cp-abi/cp-abi.c
> -rw-r--r-- dberlin/users  2244 2001-02-18 14:58 cp-abi/gnu-v2-abi.c
> 

Yes, it's temporarily empty.
It'll be filled in very shortly (read: tomorrow at the latest).

> 
> Note that since your patch is incomplete, I cannot test it. So the 
> 'approved' is conditional.
Okeydokey.
> 
> Specific comments:
> 
> 
> 
> *************** c_type_print_base (struct type *type, st
> *** 902,912 ****
>   		{
>   		  char *physname = TYPE_FN_FIELD_PHYSNAME (f, j);
>   		  int is_full_physname_constructor =
> ! 		  ((physname[0] == '_' && physname[1] == '_'
> ! 		    && strchr ("0123456789Qt", physname[2]))
> ! 		   || STREQN (physname, "__ct__", 6)
> ! 		   || DESTRUCTOR_PREFIX_P (physname)
> ! 		   || STREQN (physname, "__dt__", 6));
>   
>   		  QUIT;
>   		  if (TYPE_FN_FIELD_PROTECTED (f, j))
> --- 903,912 ----
>   		{
>   		  char *physname = TYPE_FN_FIELD_PHYSNAME (f, j);
>   		  int is_full_physname_constructor =
> ! 		   constructor_prefix_p (physname) 
> ! 		   || destructor_prefix_p (physname)
> ! 		   || STREQN (method_name, "~", 1);
> ! 		   
>   
>   		  QUIT;
>   		  if (TYPE_FN_FIELD_PROTECTED (f, j))
> 
> 
> I agree with Michael Chastain, I would prefer if there was one less
> STREQN around, given that we understand what should be used in its
> place, let's just use method_name[1] == '~'
you mean method_name[0] == '~' 
:).
But, Okeydokey.

>  
> 
> Index: dbxread.c
> ===================================================================
> RCS file: /cvs/src/src/gdb/dbxread.c,v
> retrieving revision 1.12
> diff -c -3 -p -r1.12 dbxread.c
> *** dbxread.c	2001/01/19 14:53:44	1.12
> --- dbxread.c	2001/02/18 20:42:42
> ***************
> *** 58,63 ****
> --- 58,64 ----
>   #include "demangle.h"
>   #include "language.h"		/* Needed inside partial-stab.h */
>   #include "complaints.h"
> + #include "cp-abi.h"
>   
>   #include "aout/aout64.h"
>   #include "aout/stab_gnu.h"	/* We always use GNU stabs, not native, now */
> *************** record_minimal_symbol (char *name, CORE_
> *** 514,520 ****
>   	char *tempstring = name;
>   	if (tempstring[0] == bfd_get_symbol_leading_char (objfile->obfd))
>   	  ++tempstring;
> ! 	if (VTBL_PREFIX_P ((tempstring)))
>   	  ms_type = mst_data;
>         }
>         section = SECT_OFF_DATA (objfile);
> --- 515,521 ----
>   	char *tempstring = name;
>   	if (tempstring[0] == bfd_get_symbol_leading_char (objfile->obfd))
>   	  ++tempstring;
> ! 	if (vtbl_prefix_p ((tempstring)))
>   	  ms_type = mst_data;
>         }
>         section = SECT_OFF_DATA (objfile);
> 
> Approved. Do we really need the extra parenthesis around tempstring?

No, I was just doing search and replace, i'll remove them.

> 
> Index: linespec.c
> ===================================================================
> RCS file: /cvs/src/src/gdb/linespec.c,v
> retrieving revision 1.4
> diff -c -3 -p -r1.4 linespec.c
> *** linespec.c	2000/12/15 01:01:48	1.4
> --- linespec.c	2001/02/18 20:42:42
> ***************
> *** 28,34 ****
>   #include "demangle.h"
>   #include "value.h"
>   #include "completer.h"
> ! 
>   /* Prototype for one function in parser-defs.h,
>      instead of including that entire file. */
>   
> --- 28,35 ----
>   #include "demangle.h"
>   #include "value.h"
>   #include "completer.h"
> ! #include "gdb_regex.h"
> ! #include "cp-abi.h"
>   /* Prototype for one function in parser-defs.h,
>      instead of including that entire file. */
> *************** find_methods (struct type *t, char *name
> *** 119,126 ****
>         int method_counter;
>   
>         /* FIXME: Shouldn't this just be CHECK_TYPEDEF (t)?  */
> !       t = SYMBOL_TYPE (sym_class);
> ! 
>         /* Loop over each method name.  At this level, all overloads of a name
>            are counted as a single name.  There is an inner loop which loops over
>            each overload.  */
> --- 120,126 ----
>         int method_counter;
>   
>         /* FIXME: Shouldn't this just be CHECK_TYPEDEF (t)?  */
> !       CHECK_TYPEDEF (t);
>         /* Loop over each method name.  At this level, all overloads of a name
>            are counted as a single name.  There is an inner loop which loops over
>            each overload.  */
> *************** find_methods (struct type *t, char *name
> *** 143,149 ****
>   		method_name = dem_opname;
>   	    }
>   
> ! 	  if (STREQ (name, method_name))
>   	    /* Find all the overloaded methods with that name.  */
>   	    for (field_counter = TYPE_FN_FIELDLIST_LENGTH (t, method_counter) - 1;
>   		 field_counter >= 0;
> --- 143,149 ----
>   		method_name = dem_opname;
>   	    }
>   
> ! 	  if (strcmp_iw (name, method_name) == 0)
>   	    /* Find all the overloaded methods with that name.  */
>   	    for (field_counter = TYPE_FN_FIELDLIST_LENGTH (t, method_counter) - 1;
>   		 field_counter >= 0;
> *************** find_methods (struct type *t, char *name
> *** 167,177 ****
>   		  }
>   		else
>   		  phys_name = TYPE_FN_FIELD_PHYSNAME (f, field_counter);
> ! 
>   		/* Destructor is handled by caller, dont add it to the list */
> ! 		if (DESTRUCTOR_PREFIX_P (phys_name))
>   		  continue;
> - 
>   		sym_arr[i1] = lookup_symbol (phys_name,
>   					     NULL, VAR_NAMESPACE,
>   					     (int *) NULL,
> --- 167,176 ----
>   		  }
>   		else
>   		  phys_name = TYPE_FN_FIELD_PHYSNAME (f, field_counter);
> ! 		
>   		/* Destructor is handled by caller, dont add it to the list */
> ! 		if (destructor_prefix_p (phys_name) != 0)
>   		  continue;
>   		sym_arr[i1] = lookup_symbol (phys_name,
>   					     NULL, VAR_NAMESPACE,
>   					     (int *) NULL,
>   
> 
> Could you please leave the blank lines that were there originally?
You mean the one where gdb_regex is now?
I don't know what i did to the one before destructor_prefix_p, it's
still there, it's just "not as blank" or something, I guess.

> Could you remove/update the comment/FIXME before CHECK_TYPEDEF.
Yup.

> Do we need to include gdb_regexp.h? What needs it?

No. I don't know how that slipped in there.

> 
> 
> Index: symtab.c
> ===================================================================
> RCS file: /cvs/src/src/gdb/symtab.c,v
> retrieving revision 1.28
> diff -c -3 -p -r1.28 symtab.c
> *** symtab.c	2001/01/30 02:49:36	1.28
> --- symtab.c	2001/02/18 20:42:43
> ***************
> *** 44,50 ****
>   #include "gdb_string.h"
>   #include "gdb_stat.h"
>   #include <ctype.h>
> ! 
>   /* Prototype for one function in parser-defs.h,
>      instead of including that entire file. */
>   
> --- 44,50 ----
>   #include "gdb_string.h"
>   #include "gdb_stat.h"
>   #include <ctype.h>
> ! #include "cp-abi.h"
>   /* Prototype for one function in parser-defs.h,
>      instead of including that entire file. */
>   
> *************** gdb_mangle_name (struct type *type, int 
> *** 287,293 ****
>     int is_full_physname_constructor;
>   
>     int is_constructor;
> !   int is_destructor = DESTRUCTOR_PREFIX_P (physname);
>     /* Need a new type prefix.  */
>     char *const_prefix = method->is_const ? "C" : "";
>     char *volatile_prefix = method->is_volatile ? "V" : "";
> --- 287,293 ----
>     int is_full_physname_constructor;
>   
>     int is_constructor;
> !   int is_destructor = destructor_prefix_p (physname);
>     /* Need a new type prefix.  */
>     char *const_prefix = method->is_const ? "C" : "";
>     char *volatile_prefix = method->is_volatile ? "V" : "";
> *************** gdb_mangle_name (struct type *type, int 
> *** 297,306 ****
>     if (OPNAME_PREFIX_P (field_name))
>       return xstrdup (physname);
>   
> !   is_full_physname_constructor =
> !     ((physname[0] == '_' && physname[1] == '_' &&
> !       (isdigit (physname[2]) || physname[2] == 'Q' || physname[2] == 't'))
> !      || (strncmp (physname, "__ct", 4) == 0));
>   
>     is_constructor =
>       is_full_physname_constructor || (newname && STREQ (field_name, newname));
> --- 297,303 ----
>     if (OPNAME_PREFIX_P (field_name))
>       return xstrdup (physname);
>   
> !   is_full_physname_constructor = constructor_prefix_p (physname);
>   
>     is_constructor =
>       is_full_physname_constructor || (newname && STREQ (field_name, newname));
> 
> 
> Approved.
> 
> Index: symtab.h
> ===================================================================
> RCS file: /cvs/src/src/gdb/symtab.h,v
> retrieving revision 1.18
> diff -c -3 -p -r1.18 symtab.h
> *** symtab.h	2001/02/08 06:03:54	1.18
> --- symtab.h	2001/02/18 20:42:43
> *************** struct partial_symtab
> *** 1055,1074 ****
>      '_vt$' is the old cfront-style vtables; '_VT$' is the new
>      style, using thunks (where '$' is really CPLUS_MARKER). */
>   
> - #define VTBL_PREFIX_P(NAME) \
> -   (((NAME)[0] == '_' \
> -    && (((NAME)[1] == 'V' && (NAME)[2] == 'T') \
> -        || ((NAME)[1] == 'v' && (NAME)[2] == 't')) \
> -    && is_cplus_marker ((NAME)[3])) || ((NAME)[0]=='_' && (NAME)[1]=='_' \
> -    && (NAME)[2]=='v' && (NAME)[3]=='t' && (NAME)[4]=='_'))
> - 
> - /* Macro that yields non-zero value iff NAME is the prefix for C++ destructor
> -    names.  Note that this macro is g++ specific (FIXME).  */
> - 
> - #define DESTRUCTOR_PREFIX_P(NAME) \
> -   ((NAME)[0] == '_' && is_cplus_marker ((NAME)[1]) && (NAME)[2] == '_')
>   
> - 
>   /* External variables and functions for the objects described above. */
>   
>   /* This symtab variable specifies the current file for printing source lines */
> --- 1055,1061 ----
> 
> OK.
> 

I forgot to cut the VTBL_PREFIX_P comment out, i'll do this as well.

> Elena


Index Nav: [Date Index] [Subject Index] [Author Index] [Thread Index]
Message Nav: [Date Prev] [Date Next] [Thread Prev] [Thread Next]