aboutsummaryrefslogtreecommitdiff
path: root/gdb/gnu-v2-abi.c
diff options
context:
space:
mode:
Diffstat (limited to 'gdb/gnu-v2-abi.c')
-rw-r--r--gdb/gnu-v2-abi.c332
1 files changed, 332 insertions, 0 deletions
diff --git a/gdb/gnu-v2-abi.c b/gdb/gnu-v2-abi.c
new file mode 100644
index 0000000..ad73165
--- /dev/null
+++ b/gdb/gnu-v2-abi.c
@@ -0,0 +1,332 @@
+/* Abstraction of GNU v2 abi.
+ Contributed by Daniel Berlin <dberlin@redhat.com>
+ Copyright 2001 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 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_regex.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 *);
+
+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;
+}
+
+
+/* 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 value_ptr
+gnuv2_virtual_fn_field (value_ptr * arg1p, struct fn_field * f, int j,
+ struct type * type, int offset)
+{
+ value_ptr 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. */
+ value_ptr entry, vfn, vtbl;
+ value_ptr 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)
+ {
+ value_ptr tmp = value_cast (context, value_addr (arg1));
+ VALUE_POINTED_TO_OFFSET (tmp) = 0;
+ 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 (value_ptr v, int *full, int *top, int *using_enc)
+{
+ struct type *known_type;
+ struct type *rtti_type;
+ CORE_ADDR coreptr;
+ value_ptr vp;
+ int using_enclosing = 0;
+ 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;
+
+ /*
+ If we are enclosed by something that isn't us, adjust the
+ address properly and set using_enclosing.
+ */
+ if (VALUE_ENCLOSING_TYPE(v) != VALUE_TYPE(v))
+ {
+ value_ptr tempval;
+ int bitpos = TYPE_BASECLASS_BITPOS (known_type,
+ TYPE_VPTR_FIELDNO (known_type));
+ tempval=value_field (v, TYPE_VPTR_FIELDNO(known_type));
+ VALUE_ADDRESS(tempval) += bitpos / 8;
+ vtbl=value_as_pointer (tempval);
+ using_enclosing=1;
+ }
+ else
+ {
+ vtbl=value_as_pointer(value_field(v,TYPE_VPTR_FIELDNO(known_type)));
+ using_enclosing=0;
+ }
+
+ /* Try to find a symbol that is the vtable */
+ minsym=lookup_minimal_symbol_by_pc(vtbl);
+ if (minsym==NULL
+ || (demangled_name=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;
+ }
+ if (using_enc)
+ *using_enc=using_enclosing;
+
+ return rtti_type;
+}
+
+
+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;
+}
+
+void
+_initialize_gnu_v2_abi (void)
+{
+ init_gnuv2_ops ();
+ register_cp_abi (gnu_v2_abi_ops);
+ switch_to_cp_abi ("gnu-v2");
+}