[deliverable/binutils-gdb.git] / gdb / gnu-v2-abi.c

/* Abstraction of GNU v2 abi.

   Copyright 2001, 2003 Free Software Foundation, Inc.

   Contributed by Daniel Berlin <dberlin@redhat.com>

   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 2 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, write to the Free Software
   Foundation, Inc., 59 Temple Place - Suite 330,
   Boston, MA 02111-1307, USA.  */

#include "defs.h"
#include "gdb_string.h"
#include "symtab.h"
#include "gdbtypes.h"
#include "value.h"
#include "demangle.h"
#include "cp-abi.h"

#include <ctype.h>

struct cp_abi_ops gnu_v2_abi_ops;

static int vb_match (struct type *, int, struct type *);
int gnuv2_baseclass_offset (struct type *type, int index, char *valaddr,
			    CORE_ADDR address);

static enum dtor_kinds
gnuv2_is_destructor_name (const char *name)
{
  if ((name[0] == '_' && is_cplus_marker (name[1]) && name[2] == '_')
      || strncmp (name, "__dt__", 6) == 0)
    return complete_object_dtor;
  else
    return 0;
}

static enum ctor_kinds
gnuv2_is_constructor_name (const char *name)
{
  if ((name[0] == '_' && name[1] == '_'
       && (isdigit (name[2]) || strchr ("Qt", name[2])))
      || strncmp (name, "__ct__", 6) == 0)
    return complete_object_ctor;
  else
    return 0;
}

static int
gnuv2_is_vtable_name (const char *name)
{
  return (((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] == '_'));
}

static int
gnuv2_is_operator_name (const char *name)
{
  return strncmp (name, "operator", 8) == 0;
}

\f
/* Return a virtual function as a value.
   ARG1 is the object which provides the virtual function
   table pointer.  *ARG1P is side-effected in calling this function.
   F is the list of member functions which contains the desired virtual
   function.
   J is an index into F which provides the desired virtual function.

   TYPE is the type in which F is located.  */
static struct value *
gnuv2_virtual_fn_field (struct value **arg1p, struct fn_field * f, int j,
			struct type * type, int offset)
{
  struct value *arg1 = *arg1p;
  struct type *type1 = check_typedef (VALUE_TYPE (arg1));


  struct type *entry_type;
  /* First, get the virtual function table pointer.  That comes
     with a strange type, so cast it to type `pointer to long' (which
     should serve just fine as a function type).  Then, index into
     the table, and convert final value to appropriate function type.  */
  struct value *entry;
  struct value *vfn;
  struct value *vtbl;
  struct value *vi = value_from_longest (builtin_type_int,
				     (LONGEST) TYPE_FN_FIELD_VOFFSET (f, j));
  struct type *fcontext = TYPE_FN_FIELD_FCONTEXT (f, j);
  struct type *context;
  if (fcontext == NULL)
    /* We don't have an fcontext (e.g. the program was compiled with
       g++ version 1).  Try to get the vtbl from the TYPE_VPTR_BASETYPE.
       This won't work right for multiple inheritance, but at least we
       should do as well as GDB 3.x did.  */
    fcontext = TYPE_VPTR_BASETYPE (type);
  context = lookup_pointer_type (fcontext);
  /* Now context is a pointer to the basetype containing the vtbl.  */
  if (TYPE_TARGET_TYPE (context) != type1)
    {
      struct value *tmp = value_cast (context, value_addr (arg1));
      arg1 = value_ind (tmp);
      type1 = check_typedef (VALUE_TYPE (arg1));
    }

  context = type1;
  /* Now context is the basetype containing the vtbl.  */

  /* This type may have been defined before its virtual function table
     was.  If so, fill in the virtual function table entry for the
     type now.  */
  if (TYPE_VPTR_FIELDNO (context) < 0)
    fill_in_vptr_fieldno (context);

  /* The virtual function table is now an array of structures
     which have the form { int16 offset, delta; void *pfn; }.  */
  vtbl = value_primitive_field (arg1, 0, TYPE_VPTR_FIELDNO (context),
				TYPE_VPTR_BASETYPE (context));

  /* With older versions of g++, the vtbl field pointed to an array
     of structures.  Nowadays it points directly to the structure. */
  if (TYPE_CODE (VALUE_TYPE (vtbl)) == TYPE_CODE_PTR
      && TYPE_CODE (TYPE_TARGET_TYPE (VALUE_TYPE (vtbl))) == TYPE_CODE_ARRAY)
    {
      /* Handle the case where the vtbl field points to an
         array of structures. */
      vtbl = value_ind (vtbl);

      /* Index into the virtual function table.  This is hard-coded because
         looking up a field is not cheap, and it may be important to save
         time, e.g. if the user has set a conditional breakpoint calling
         a virtual function.  */
      entry = value_subscript (vtbl, vi);
    }
  else
    {
      /* Handle the case where the vtbl field points directly to a structure. */
      vtbl = value_add (vtbl, vi);
      entry = value_ind (vtbl);
    }

  entry_type = check_typedef (VALUE_TYPE (entry));

  if (TYPE_CODE (entry_type) == TYPE_CODE_STRUCT)
    {
      /* Move the `this' pointer according to the virtual function table. */
      VALUE_OFFSET (arg1) += value_as_long (value_field (entry, 0));

      if (!VALUE_LAZY (arg1))
	{
	  VALUE_LAZY (arg1) = 1;
	  value_fetch_lazy (arg1);
	}

      vfn = value_field (entry, 2);
    }
  else if (TYPE_CODE (entry_type) == TYPE_CODE_PTR)
    vfn = entry;
  else
    error ("I'm confused:  virtual function table has bad type");
  /* Reinstantiate the function pointer with the correct type.  */
  VALUE_TYPE (vfn) = lookup_pointer_type (TYPE_FN_FIELD_TYPE (f, j));

  *arg1p = arg1;
  return vfn;
}


struct type *
gnuv2_value_rtti_type (struct value *v, int *full, int *top, int *using_enc)
{
  struct type *known_type;
  struct type *rtti_type;
  CORE_ADDR coreptr;
  struct value *vp;
  long top_offset = 0;
  char rtti_type_name[256];
  CORE_ADDR vtbl;
  struct minimal_symbol *minsym;
  struct symbol *sym;
  char *demangled_name;
  struct type *btype;

  if (full)
    *full = 0;
  if (top)
    *top = -1;
  if (using_enc)
    *using_enc = 0;

  /* Get declared type */
  known_type = VALUE_TYPE (v);
  CHECK_TYPEDEF (known_type);
  /* RTTI works only or class objects */
  if (TYPE_CODE (known_type) != TYPE_CODE_CLASS)
    return NULL;

  /* Plan on this changing in the future as i get around to setting
     the vtables properly for G++ compiled stuff.  Also, I'll be using
     the type info functions, which are always right.  Deal with it
     until then.  */

  /* If the type has no vptr fieldno, try to get it filled in */
  if (TYPE_VPTR_FIELDNO(known_type) < 0)
    fill_in_vptr_fieldno(known_type);

  /* If we still can't find one, give up */
  if (TYPE_VPTR_FIELDNO(known_type) < 0)
    return NULL;

  /* Make sure our basetype and known type match, otherwise, cast
     so we can get at the vtable properly.
  */
  btype = TYPE_VPTR_BASETYPE (known_type);
  CHECK_TYPEDEF (btype);
  if (btype != known_type )
    {
      v = value_cast (btype, v);
      if (using_enc)
        *using_enc=1;
    }
  /*
    We can't use value_ind here, because it would want to use RTTI, and
    we'd waste a bunch of time figuring out we already know the type.
    Besides, we don't care about the type, just the actual pointer
  */
  if (VALUE_ADDRESS (value_field (v, TYPE_VPTR_FIELDNO (known_type))) == 0)
    return NULL;

  vtbl=value_as_address(value_field(v,TYPE_VPTR_FIELDNO(known_type)));

  /* Try to find a symbol that is the vtable */
  minsym=lookup_minimal_symbol_by_pc(vtbl);
  if (minsym==NULL
      || (demangled_name=DEPRECATED_SYMBOL_NAME (minsym))==NULL
      || !is_vtable_name (demangled_name))
    return NULL;

  /* If we just skip the prefix, we get screwed by namespaces */
  demangled_name=cplus_demangle(demangled_name,DMGL_PARAMS|DMGL_ANSI);
  *(strchr(demangled_name,' '))=0;

  /* Lookup the type for the name */
  rtti_type=lookup_typename(demangled_name, (struct block *)0,1);

  if (rtti_type==NULL)
    return NULL;

  if (TYPE_N_BASECLASSES(rtti_type) > 1 &&  full && (*full) != 1)
    {
      if (top)
        *top=TYPE_BASECLASS_BITPOS(rtti_type,TYPE_VPTR_FIELDNO(rtti_type))/8;
      if (top && ((*top) >0))
        {
          if (TYPE_LENGTH(rtti_type) > TYPE_LENGTH(known_type))
            {
              if (full)
                *full=0;
            }
          else
            {
              if (full)
                *full=1;
            }
        }
    }
  else
    {
      if (full)
        *full=1;
    }

  return rtti_type;
}

/* Return true if the INDEXth field of TYPE is a virtual baseclass
   pointer which is for the base class whose type is BASECLASS.  */

static int
vb_match (struct type *type, int index, struct type *basetype)
{
  struct type *fieldtype;
  char *name = TYPE_FIELD_NAME (type, index);
  char *field_class_name = NULL;

  if (*name != '_')
    return 0;
  /* gcc 2.4 uses _vb$.  */
  if (name[1] == 'v' && name[2] == 'b' && is_cplus_marker (name[3]))
    field_class_name = name + 4;
  /* gcc 2.5 will use __vb_.  */
  if (name[1] == '_' && name[2] == 'v' && name[3] == 'b' && name[4] == '_')
    field_class_name = name + 5;

  if (field_class_name == NULL)
    /* This field is not a virtual base class pointer.  */
    return 0;

  /* It's a virtual baseclass pointer, now we just need to find out whether
     it is for this baseclass.  */
  fieldtype = TYPE_FIELD_TYPE (type, index);
  if (fieldtype == NULL
      || TYPE_CODE (fieldtype) != TYPE_CODE_PTR)
    /* "Can't happen".  */
    return 0;

  /* What we check for is that either the types are equal (needed for
     nameless types) or have the same name.  This is ugly, and a more
     elegant solution should be devised (which would probably just push
     the ugliness into symbol reading unless we change the stabs format).  */
  if (TYPE_TARGET_TYPE (fieldtype) == basetype)
    return 1;

  if (TYPE_NAME (basetype) != NULL
      && TYPE_NAME (TYPE_TARGET_TYPE (fieldtype)) != NULL
      && strcmp (TYPE_NAME (basetype),
		 TYPE_NAME (TYPE_TARGET_TYPE (fieldtype))) == 0)
    return 1;
  return 0;
}

/* Compute the offset of the baseclass which is
   the INDEXth baseclass of class TYPE,
   for value at VALADDR (in host) at ADDRESS (in target).
   The result is the offset of the baseclass value relative
   to (the address of)(ARG) + OFFSET.

   -1 is returned on error. */

int
gnuv2_baseclass_offset (struct type *type, int index, char *valaddr,
		  CORE_ADDR address)
{
  struct type *basetype = TYPE_BASECLASS (type, index);

  if (BASETYPE_VIA_VIRTUAL (type, index))
    {
      /* Must hunt for the pointer to this virtual baseclass.  */
      register int i, len = TYPE_NFIELDS (type);
      register int n_baseclasses = TYPE_N_BASECLASSES (type);

      /* First look for the virtual baseclass pointer
         in the fields.  */
      for (i = n_baseclasses; i < len; i++)
	{
	  if (vb_match (type, i, basetype))
	    {
	      CORE_ADDR addr
	      = unpack_pointer (TYPE_FIELD_TYPE (type, i),
				valaddr + (TYPE_FIELD_BITPOS (type, i) / 8));

	      return addr - (LONGEST) address;
	    }
	}
      /* Not in the fields, so try looking through the baseclasses.  */
      for (i = index + 1; i < n_baseclasses; i++)
	{
	  int boffset =
	  baseclass_offset (type, i, valaddr, address);
	  if (boffset)
	    return boffset;
	}
      /* Not found.  */
      return -1;
    }

  /* Baseclass is easily computed.  */
  return TYPE_BASECLASS_BITPOS (type, index) / 8;
}

static void
init_gnuv2_ops (void)
{
  gnu_v2_abi_ops.shortname = "gnu-v2";
  gnu_v2_abi_ops.longname = "GNU G++ Version 2 ABI";
  gnu_v2_abi_ops.doc = "G++ Version 2 ABI";
  gnu_v2_abi_ops.is_destructor_name = gnuv2_is_destructor_name;
  gnu_v2_abi_ops.is_constructor_name = gnuv2_is_constructor_name;
  gnu_v2_abi_ops.is_vtable_name = gnuv2_is_vtable_name;
  gnu_v2_abi_ops.is_operator_name = gnuv2_is_operator_name;
  gnu_v2_abi_ops.virtual_fn_field = gnuv2_virtual_fn_field;
  gnu_v2_abi_ops.rtti_type = gnuv2_value_rtti_type;
  gnu_v2_abi_ops.baseclass_offset = gnuv2_baseclass_offset;
}

void
_initialize_gnu_v2_abi (void)
{
  init_gnuv2_ops ();
  register_cp_abi (&gnu_v2_abi_ops);
  set_cp_abi_as_auto_default (gnu_v2_abi_ops.shortname);
}
Commit	Line	Data
015a42b4	1	/* Abstraction of GNU v2 abi.
1bac305b AC	2
	3	Copyright 2001, 2003 Free Software Foundation, Inc.
	4
015a42b4	5	Contributed by Daniel Berlin <dberlin@redhat.com>
015a42b4 JB	6
	7	This file is part of GDB.
	8
	9	This program is free software; you can redistribute it and/or
	10	modify
	11	it under the terms of the GNU General Public License as published
	12	by
	13	the Free Software Foundation; either version 2 of the License, or
	14	(at your option) any later version.
	15
	16	This program is distributed in the hope that it will be useful,
	17	but WITHOUT ANY WARRANTY; without even the implied warranty of
	18	MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
	19	GNU General Public License for more details.
	20
	21	You should have received a copy of the GNU General Public License
	22	along with this program; if not, write to the Free Software
	23	Foundation, Inc., 59 Temple Place - Suite 330,
	24	Boston, MA 02111-1307, USA. */
	25
	26	#include "defs.h"
015a42b4 JB	27	#include "gdb_string.h"
	28	#include "symtab.h"
	29	#include "gdbtypes.h"
	30	#include "value.h"
	31	#include "demangle.h"
	32	#include "cp-abi.h"
	33
	34	#include <ctype.h>
	35
	36	struct cp_abi_ops gnu_v2_abi_ops;
	37
	38	static int vb_match (struct type , int, struct type );
1514d34e DJ	39	int gnuv2_baseclass_offset (struct type type, int index, char valaddr,
1514d34e DJ	40	CORE_ADDR address);
015a42b4 JB	41
	42	static enum dtor_kinds
	43	gnuv2_is_destructor_name (const char *name)
	44	{
	45	if ((name[0] == '_' && is_cplus_marker (name[1]) && name[2] == '_')
	46	\|\| strncmp (name, "__dt__", 6) == 0)
	47	return complete_object_dtor;
	48	else
	49	return 0;
	50	}
	51
	52	static enum ctor_kinds
	53	gnuv2_is_constructor_name (const char *name)
	54	{
	55	if ((name[0] == '_' && name[1] == '_'
	56	&& (isdigit (name[2]) \|\| strchr ("Qt", name[2])))
	57	\|\| strncmp (name, "__ct__", 6) == 0)
	58	return complete_object_ctor;
	59	else
	60	return 0;
	61	}
	62
	63	static int
	64	gnuv2_is_vtable_name (const char *name)
	65	{
	66	return (((name)[0] == '_'
	67	&& (((name)[1] == 'V' && (name)[2] == 'T')
	68	\|\| ((name)[1] == 'v' && (name)[2] == 't'))
	69	&& is_cplus_marker ((name)[3])) \|\|
	70	((name)[0] == '_' && (name)[1] == '_'
	71	&& (name)[2] == 'v' && (name)[3] == 't' && (name)[4] == '_'));
	72	}
	73
	74	static int
	75	gnuv2_is_operator_name (const char *name)
	76	{
	77	return strncmp (name, "operator", 8) == 0;
	78	}
	79
	80	\f
	81	/* Return a virtual function as a value.
	82	ARG1 is the object which provides the virtual function
	83	table pointer. *ARG1P is side-effected in calling this function.
	84	F is the list of member functions which contains the desired virtual
	85	function.
	86	J is an index into F which provides the desired virtual function.
	87
	88	TYPE is the type in which F is located. */
e933e538 AC	89	static struct value *
e933e538 AC	90	gnuv2_virtual_fn_field (struct value *arg1p, struct fn_field f, int j,
015a42b4 JB	91	struct type * type, int offset)
015a42b4 JB	92	{
e933e538	93	struct value arg1 = arg1p;
015a42b4 JB	94	struct type *type1 = check_typedef (VALUE_TYPE (arg1));
	95
	96
	97	struct type *entry_type;
	98	/* First, get the virtual function table pointer. That comes
	99	with a strange type, so cast it to type `pointer to long' (which
	100	should serve just fine as a function type). Then, index into
	101	the table, and convert final value to appropriate function type. */
e933e538 AC	102	struct value *entry;
	103	struct value *vfn;
	104	struct value *vtbl;
	105	struct value *vi = value_from_longest (builtin_type_int,
015a42b4 JB	106	(LONGEST) TYPE_FN_FIELD_VOFFSET (f, j));
	107	struct type *fcontext = TYPE_FN_FIELD_FCONTEXT (f, j);
	108	struct type *context;
	109	if (fcontext == NULL)
	110	/* We don't have an fcontext (e.g. the program was compiled with
	111	g++ version 1). Try to get the vtbl from the TYPE_VPTR_BASETYPE.
	112	This won't work right for multiple inheritance, but at least we
	113	should do as well as GDB 3.x did. */
	114	fcontext = TYPE_VPTR_BASETYPE (type);
	115	context = lookup_pointer_type (fcontext);
	116	/* Now context is a pointer to the basetype containing the vtbl. */
	117	if (TYPE_TARGET_TYPE (context) != type1)
	118	{
e933e538	119	struct value *tmp = value_cast (context, value_addr (arg1));
015a42b4 JB	120	arg1 = value_ind (tmp);
	121	type1 = check_typedef (VALUE_TYPE (arg1));
	122	}
	123
	124	context = type1;
	125	/* Now context is the basetype containing the vtbl. */
	126
	127	/* This type may have been defined before its virtual function table
	128	was. If so, fill in the virtual function table entry for the
	129	type now. */
	130	if (TYPE_VPTR_FIELDNO (context) < 0)
	131	fill_in_vptr_fieldno (context);
	132
	133	/* The virtual function table is now an array of structures
	134	which have the form { int16 offset, delta; void pfn; }. /
	135	vtbl = value_primitive_field (arg1, 0, TYPE_VPTR_FIELDNO (context),
	136	TYPE_VPTR_BASETYPE (context));
	137
	138	/* With older versions of g++, the vtbl field pointed to an array
	139	of structures. Nowadays it points directly to the structure. */
	140	if (TYPE_CODE (VALUE_TYPE (vtbl)) == TYPE_CODE_PTR
	141	&& TYPE_CODE (TYPE_TARGET_TYPE (VALUE_TYPE (vtbl))) == TYPE_CODE_ARRAY)
	142	{
	143	/* Handle the case where the vtbl field points to an
	144	array of structures. */
	145	vtbl = value_ind (vtbl);
	146
	147	/* Index into the virtual function table. This is hard-coded because
	148	looking up a field is not cheap, and it may be important to save
	149	time, e.g. if the user has set a conditional breakpoint calling
	150	a virtual function. */
	151	entry = value_subscript (vtbl, vi);
	152	}
	153	else
	154	{
	155	/* Handle the case where the vtbl field points directly to a structure. */
	156	vtbl = value_add (vtbl, vi);
	157	entry = value_ind (vtbl);
	158	}
	159
	160	entry_type = check_typedef (VALUE_TYPE (entry));
	161
	162	if (TYPE_CODE (entry_type) == TYPE_CODE_STRUCT)
	163	{
	164	/* Move the `this' pointer according to the virtual function table. */
	165	VALUE_OFFSET (arg1) += value_as_long (value_field (entry, 0));
	166
	167	if (!VALUE_LAZY (arg1))
	168	{
	169	VALUE_LAZY (arg1) = 1;
	170	value_fetch_lazy (arg1);
	171	}
	172
	173	vfn = value_field (entry, 2);
	174	}
	175	else if (TYPE_CODE (entry_type) == TYPE_CODE_PTR)
	176	vfn = entry;
	177	else
	178	error ("I'm confused: virtual function table has bad type");
	179	/* Reinstantiate the function pointer with the correct type. */
	180	VALUE_TYPE (vfn) = lookup_pointer_type (TYPE_FN_FIELD_TYPE (f, j));
	181
	182	*arg1p = arg1;
	183	return vfn;
184	}
185
186
187	struct type *
e933e538	188	gnuv2_value_rtti_type (struct value v, int full, int top, int using_enc)
015a42b4 JB	189	{
	190	struct type *known_type;
	191	struct type *rtti_type;
	192	CORE_ADDR coreptr;
e933e538	193	struct value *vp;
015a42b4 JB	194	long top_offset = 0;
	195	char rtti_type_name[256];
	196	CORE_ADDR vtbl;
	197	struct minimal_symbol *minsym;
	198	struct symbol *sym;
	199	char *demangled_name;
	200	struct type *btype;
	201
	202	if (full)
	203	*full = 0;
	204	if (top)
	205	*top = -1;
	206	if (using_enc)
	207	*using_enc = 0;
	208
	209	/* Get declared type */
	210	known_type = VALUE_TYPE (v);
	211	CHECK_TYPEDEF (known_type);
	212	/* RTTI works only or class objects */
	213	if (TYPE_CODE (known_type) != TYPE_CODE_CLASS)
	214	return NULL;
	215
	216	/* Plan on this changing in the future as i get around to setting
	217	the vtables properly for G++ compiled stuff. Also, I'll be using
	218	the type info functions, which are always right. Deal with it
	219	until then. */
	220
	221	/* If the type has no vptr fieldno, try to get it filled in */
	222	if (TYPE_VPTR_FIELDNO(known_type) < 0)
	223	fill_in_vptr_fieldno(known_type);
	224
	225	/* If we still can't find one, give up */
	226	if (TYPE_VPTR_FIELDNO(known_type) < 0)
	227	return NULL;
	228
	229	/* Make sure our basetype and known type match, otherwise, cast
	230	so we can get at the vtable properly.
	231	*/
	232	btype = TYPE_VPTR_BASETYPE (known_type);
	233	CHECK_TYPEDEF (btype);
	234	if (btype != known_type )
	235	{
	236	v = value_cast (btype, v);
	237	if (using_enc)
	238	*using_enc=1;
	239	}
	240	/*
	241	We can't use value_ind here, because it would want to use RTTI, and
	242	we'd waste a bunch of time figuring out we already know the type.
	243	Besides, we don't care about the type, just the actual pointer
	244	*/
	245	if (VALUE_ADDRESS (value_field (v, TYPE_VPTR_FIELDNO (known_type))) == 0)
	246	return NULL;
	247
2a73a662	248	vtbl=value_as_address(value_field(v,TYPE_VPTR_FIELDNO(known_type)));
015a42b4 JB	249
	250	/* Try to find a symbol that is the vtable */
	251	minsym=lookup_minimal_symbol_by_pc(vtbl);
	252	if (minsym==NULL
22abf04a	253	\|\| (demangled_name=DEPRECATED_SYMBOL_NAME (minsym))==NULL
015a42b4 JB	254	\|\| !is_vtable_name (demangled_name))
	255	return NULL;
	256
	257	/* If we just skip the prefix, we get screwed by namespaces */
	258	demangled_name=cplus_demangle(demangled_name,DMGL_PARAMS\|DMGL_ANSI);
	259	*(strchr(demangled_name,' '))=0;
	260
	261	/* Lookup the type for the name */
	262	rtti_type=lookup_typename(demangled_name, (struct block *)0,1);
	263
	264	if (rtti_type==NULL)
	265	return NULL;
	266
	267	if (TYPE_N_BASECLASSES(rtti_type) > 1 && full && (*full) != 1)
	268	{
	269	if (top)
	270	*top=TYPE_BASECLASS_BITPOS(rtti_type,TYPE_VPTR_FIELDNO(rtti_type))/8;
	271	if (top && ((*top) >0))
	272	{
	273	if (TYPE_LENGTH(rtti_type) > TYPE_LENGTH(known_type))
	274	{
	275	if (full)
	276	*full=0;
	277	}
	278	else
	279	{
	280	if (full)
	281	*full=1;
	282	}
	283	}
	284	}
	285	else
	286	{
	287	if (full)
	288	*full=1;
	289	}
015a42b4 JB	290
	291	return rtti_type;
	292	}
	293
1514d34e DJ	294	/* Return true if the INDEXth field of TYPE is a virtual baseclass
	295	pointer which is for the base class whose type is BASECLASS. */
	296
	297	static int
	298	vb_match (struct type type, int index, struct type basetype)
	299	{
	300	struct type *fieldtype;
	301	char *name = TYPE_FIELD_NAME (type, index);
	302	char *field_class_name = NULL;
	303
	304	if (*name != '_')
	305	return 0;
	306	/* gcc 2.4 uses _vb$. */
	307	if (name[1] == 'v' && name[2] == 'b' && is_cplus_marker (name[3]))
	308	field_class_name = name + 4;
	309	/* gcc 2.5 will use __vb_. */
	310	if (name[1] == '_' && name[2] == 'v' && name[3] == 'b' && name[4] == '_')
	311	field_class_name = name + 5;
	312
	313	if (field_class_name == NULL)
	314	/* This field is not a virtual base class pointer. */
	315	return 0;
	316
	317	/* It's a virtual baseclass pointer, now we just need to find out whether
	318	it is for this baseclass. */
	319	fieldtype = TYPE_FIELD_TYPE (type, index);
	320	if (fieldtype == NULL
	321	\|\| TYPE_CODE (fieldtype) != TYPE_CODE_PTR)
	322	/* "Can't happen". */
	323	return 0;
	324
	325	/* What we check for is that either the types are equal (needed for
	326	nameless types) or have the same name. This is ugly, and a more
	327	elegant solution should be devised (which would probably just push
	328	the ugliness into symbol reading unless we change the stabs format). */
	329	if (TYPE_TARGET_TYPE (fieldtype) == basetype)
	330	return 1;
	331
	332	if (TYPE_NAME (basetype) != NULL
	333	&& TYPE_NAME (TYPE_TARGET_TYPE (fieldtype)) != NULL
bde58177 AC	334	&& strcmp (TYPE_NAME (basetype),
bde58177 AC	335	TYPE_NAME (TYPE_TARGET_TYPE (fieldtype))) == 0)
1514d34e DJ	336	return 1;
	337	return 0;
	338	}
	339
	340	/* Compute the offset of the baseclass which is
	341	the INDEXth baseclass of class TYPE,
	342	for value at VALADDR (in host) at ADDRESS (in target).
	343	The result is the offset of the baseclass value relative
	344	to (the address of)(ARG) + OFFSET.
	345
	346	-1 is returned on error. */
	347
	348	int
	349	gnuv2_baseclass_offset (struct type type, int index, char valaddr,
	350	CORE_ADDR address)
	351	{
	352	struct type *basetype = TYPE_BASECLASS (type, index);
	353
	354	if (BASETYPE_VIA_VIRTUAL (type, index))
	355	{
	356	/* Must hunt for the pointer to this virtual baseclass. */
	357	register int i, len = TYPE_NFIELDS (type);
	358	register int n_baseclasses = TYPE_N_BASECLASSES (type);
	359
	360	/* First look for the virtual baseclass pointer
	361	in the fields. */
	362	for (i = n_baseclasses; i < len; i++)
	363	{
	364	if (vb_match (type, i, basetype))
	365	{
	366	CORE_ADDR addr
	367	= unpack_pointer (TYPE_FIELD_TYPE (type, i),
	368	valaddr + (TYPE_FIELD_BITPOS (type, i) / 8));
	369
	370	return addr - (LONGEST) address;
	371	}
	372	}
	373	/* Not in the fields, so try looking through the baseclasses. */
	374	for (i = index + 1; i < n_baseclasses; i++)
	375	{
	376	int boffset =
	377	baseclass_offset (type, i, valaddr, address);
	378	if (boffset)
	379	return boffset;
	380	}
	381	/* Not found. */
	382	return -1;
	383	}
	384
	385	/* Baseclass is easily computed. */
	386	return TYPE_BASECLASS_BITPOS (type, index) / 8;
	387	}
015a42b4 JB	388
	389	static void
	390	init_gnuv2_ops (void)
	391	{
	392	gnu_v2_abi_ops.shortname = "gnu-v2";
	393	gnu_v2_abi_ops.longname = "GNU G++ Version 2 ABI";
	394	gnu_v2_abi_ops.doc = "G++ Version 2 ABI";
	395	gnu_v2_abi_ops.is_destructor_name = gnuv2_is_destructor_name;
	396	gnu_v2_abi_ops.is_constructor_name = gnuv2_is_constructor_name;
	397	gnu_v2_abi_ops.is_vtable_name = gnuv2_is_vtable_name;
	398	gnu_v2_abi_ops.is_operator_name = gnuv2_is_operator_name;
	399	gnu_v2_abi_ops.virtual_fn_field = gnuv2_virtual_fn_field;
	400	gnu_v2_abi_ops.rtti_type = gnuv2_value_rtti_type;
1514d34e	401	gnu_v2_abi_ops.baseclass_offset = gnuv2_baseclass_offset;
015a42b4 JB	402	}
	403
	404	void
	405	_initialize_gnu_v2_abi (void)
	406	{
	407	init_gnuv2_ops ();
fe1f4a5e DJ	408	register_cp_abi (&gnu_v2_abi_ops);
fe1f4a5e DJ	409	set_cp_abi_as_auto_default (gnu_v2_abi_ops.shortname);
015a42b4	410	}