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492d29ea1c
This patch splits the TRY_CATCH macro into three, so that we go from this: ~~~ volatile gdb_exception ex; TRY_CATCH (ex, RETURN_MASK_ERROR) { } if (ex.reason < 0) { } ~~~ to this: ~~~ TRY { } CATCH (ex, RETURN_MASK_ERROR) { } END_CATCH ~~~ Thus, we'll be getting rid of the local volatile exception object, and declaring the caught exception in the catch block. This allows reimplementing TRY/CATCH in terms of C++ exceptions when building in C++ mode, while still allowing to build GDB in C mode (using setjmp/longjmp), as a transition step. TBC, after this patch, is it _not_ valid to have code between the TRY and the CATCH blocks, like: TRY { } // some code here. CATCH (ex, RETURN_MASK_ERROR) { } END_CATCH Just like it isn't valid to do that with C++'s native try/catch. By switching to creating the exception object inside the CATCH block scope, we can get rid of all the explicitly allocated volatile exception objects all over the tree, and map the CATCH block more directly to C++'s catch blocks. The majority of the TRY_CATCH -> TRY+CATCH+END_CATCH conversion was done with a script, rerun from scratch at every rebase, no manual editing involved. After the mechanical conversion, a few places needed manual intervention, to fix preexisting cases where we were using the exception object outside of the TRY_CATCH block, and cases where we were using "else" after a 'if (ex.reason) < 0)' [a CATCH after this patch]. The result was folded into this patch so that GDB still builds at each incremental step. END_CATCH is necessary for two reasons: First, because we name the exception object in the CATCH block, which requires creating a scope, which in turn must be closed somewhere. Declaring the exception variable in the initializer field of a for block, like: #define CATCH(EXCEPTION, mask) \ for (struct gdb_exception EXCEPTION; \ exceptions_state_mc_catch (&EXCEPTION, MASK); \ EXCEPTION = exception_none) would avoid needing END_CATCH, but alas, in C mode, we build with C90, which doesn't allow mixed declarations and code. Second, because when TRY/CATCH are wired to real C++ try/catch, as long as we need to handle cleanup chains, even if there's no CATCH block that wants to catch the exception, we need for stop at every frame in the unwind chain and run cleanups, then rethrow. That will be done in END_CATCH. After we require C++, we'll still need TRY/CATCH/END_CATCH until cleanups are completely phased out -- TRY/CATCH in C++ mode will save/restore the current cleanup chain, like in C mode, and END_CATCH catches otherwise uncaugh exceptions, runs cleanups and rethrows, so that C++ cleanups and exceptions can coexist. IMO, this still makes the TRY/CATCH code look a bit more like a newcomer would expect, so IMO worth it even if we weren't considering C++. gdb/ChangeLog. 2015-03-07 Pedro Alves <palves@redhat.com> * common/common-exceptions.c (struct catcher) <exception>: No longer a pointer to volatile exception. Now an exception value. <mask>: Delete field. (exceptions_state_mc_init): Remove all parameters. Adjust. (exceptions_state_mc): No longer pop the catcher here. (exceptions_state_mc_catch): New function. (throw_exception): Adjust. * common/common-exceptions.h (exceptions_state_mc_init): Remove all parameters. (exceptions_state_mc_catch): Declare. (TRY_CATCH): Rename to ... (TRY): ... this. Remove EXCEPTION and MASK parameters. (CATCH, END_CATCH): New. All callers adjusted. gdb/gdbserver/ChangeLog: 2015-03-07 Pedro Alves <palves@redhat.com> Adjust all callers of TRY_CATCH to use TRY/CATCH/END_CATCH instead.
1413 lines
44 KiB
C
1413 lines
44 KiB
C
/* Abstraction of GNU v3 abi.
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Contributed by Jim Blandy <jimb@redhat.com>
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Copyright (C) 2001-2015 Free Software Foundation, Inc.
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This file is part of GDB.
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This program is free software; you can redistribute it and/or modify
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it under the terms of the GNU General Public License as published by
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the Free Software Foundation; either version 3 of the License, or
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(at your option) any later version.
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This program is distributed in the hope that it will be useful,
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but WITHOUT ANY WARRANTY; without even the implied warranty of
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MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
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GNU General Public License for more details.
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You should have received a copy of the GNU General Public License
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along with this program. If not, see <http://www.gnu.org/licenses/>. */
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#include "defs.h"
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#include "value.h"
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#include "cp-abi.h"
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#include "cp-support.h"
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#include "demangle.h"
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#include "objfiles.h"
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#include "valprint.h"
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#include "c-lang.h"
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#include "typeprint.h"
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static struct cp_abi_ops gnu_v3_abi_ops;
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/* A gdbarch key for std::type_info, in the event that it can't be
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found in the debug info. */
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static struct gdbarch_data *std_type_info_gdbarch_data;
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static int
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gnuv3_is_vtable_name (const char *name)
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{
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return startswith (name, "_ZTV");
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}
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static int
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gnuv3_is_operator_name (const char *name)
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{
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return startswith (name, "operator");
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}
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/* To help us find the components of a vtable, we build ourselves a
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GDB type object representing the vtable structure. Following the
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V3 ABI, it goes something like this:
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struct gdb_gnu_v3_abi_vtable {
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/ * An array of virtual call and virtual base offsets. The real
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length of this array depends on the class hierarchy; we use
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negative subscripts to access the elements. Yucky, but
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better than the alternatives. * /
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ptrdiff_t vcall_and_vbase_offsets[0];
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/ * The offset from a virtual pointer referring to this table
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to the top of the complete object. * /
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ptrdiff_t offset_to_top;
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/ * The type_info pointer for this class. This is really a
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std::type_info *, but GDB doesn't really look at the
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type_info object itself, so we don't bother to get the type
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exactly right. * /
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void *type_info;
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/ * Virtual table pointers in objects point here. * /
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/ * Virtual function pointers. Like the vcall/vbase array, the
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real length of this table depends on the class hierarchy. * /
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void (*virtual_functions[0]) ();
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};
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The catch, of course, is that the exact layout of this table
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depends on the ABI --- word size, endianness, alignment, etc. So
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the GDB type object is actually a per-architecture kind of thing.
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vtable_type_gdbarch_data is a gdbarch per-architecture data pointer
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which refers to the struct type * for this structure, laid out
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appropriately for the architecture. */
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static struct gdbarch_data *vtable_type_gdbarch_data;
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/* Human-readable names for the numbers of the fields above. */
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enum {
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vtable_field_vcall_and_vbase_offsets,
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vtable_field_offset_to_top,
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vtable_field_type_info,
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vtable_field_virtual_functions
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};
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/* Return a GDB type representing `struct gdb_gnu_v3_abi_vtable',
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described above, laid out appropriately for ARCH.
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We use this function as the gdbarch per-architecture data
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initialization function. */
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static void *
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build_gdb_vtable_type (struct gdbarch *arch)
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{
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struct type *t;
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struct field *field_list, *field;
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int offset;
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struct type *void_ptr_type
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= builtin_type (arch)->builtin_data_ptr;
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struct type *ptr_to_void_fn_type
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= builtin_type (arch)->builtin_func_ptr;
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/* ARCH can't give us the true ptrdiff_t type, so we guess. */
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struct type *ptrdiff_type
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= arch_integer_type (arch, gdbarch_ptr_bit (arch), 0, "ptrdiff_t");
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/* We assume no padding is necessary, since GDB doesn't know
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anything about alignment at the moment. If this assumption bites
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us, we should add a gdbarch method which, given a type, returns
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the alignment that type requires, and then use that here. */
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/* Build the field list. */
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field_list = xmalloc (sizeof (struct field [4]));
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memset (field_list, 0, sizeof (struct field [4]));
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field = &field_list[0];
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offset = 0;
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/* ptrdiff_t vcall_and_vbase_offsets[0]; */
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FIELD_NAME (*field) = "vcall_and_vbase_offsets";
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FIELD_TYPE (*field) = lookup_array_range_type (ptrdiff_type, 0, -1);
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SET_FIELD_BITPOS (*field, offset * TARGET_CHAR_BIT);
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offset += TYPE_LENGTH (FIELD_TYPE (*field));
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field++;
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/* ptrdiff_t offset_to_top; */
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FIELD_NAME (*field) = "offset_to_top";
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FIELD_TYPE (*field) = ptrdiff_type;
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SET_FIELD_BITPOS (*field, offset * TARGET_CHAR_BIT);
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offset += TYPE_LENGTH (FIELD_TYPE (*field));
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field++;
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/* void *type_info; */
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FIELD_NAME (*field) = "type_info";
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FIELD_TYPE (*field) = void_ptr_type;
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SET_FIELD_BITPOS (*field, offset * TARGET_CHAR_BIT);
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offset += TYPE_LENGTH (FIELD_TYPE (*field));
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field++;
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/* void (*virtual_functions[0]) (); */
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FIELD_NAME (*field) = "virtual_functions";
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FIELD_TYPE (*field) = lookup_array_range_type (ptr_to_void_fn_type, 0, -1);
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SET_FIELD_BITPOS (*field, offset * TARGET_CHAR_BIT);
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offset += TYPE_LENGTH (FIELD_TYPE (*field));
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field++;
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/* We assumed in the allocation above that there were four fields. */
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gdb_assert (field == (field_list + 4));
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t = arch_type (arch, TYPE_CODE_STRUCT, offset, NULL);
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TYPE_NFIELDS (t) = field - field_list;
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TYPE_FIELDS (t) = field_list;
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TYPE_TAG_NAME (t) = "gdb_gnu_v3_abi_vtable";
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INIT_CPLUS_SPECIFIC (t);
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return make_type_with_address_space (t, TYPE_INSTANCE_FLAG_CODE_SPACE);
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}
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/* Return the ptrdiff_t type used in the vtable type. */
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static struct type *
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vtable_ptrdiff_type (struct gdbarch *gdbarch)
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{
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struct type *vtable_type = gdbarch_data (gdbarch, vtable_type_gdbarch_data);
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/* The "offset_to_top" field has the appropriate (ptrdiff_t) type. */
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return TYPE_FIELD_TYPE (vtable_type, vtable_field_offset_to_top);
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}
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/* Return the offset from the start of the imaginary `struct
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gdb_gnu_v3_abi_vtable' object to the vtable's "address point"
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(i.e., where objects' virtual table pointers point). */
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static int
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vtable_address_point_offset (struct gdbarch *gdbarch)
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{
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struct type *vtable_type = gdbarch_data (gdbarch, vtable_type_gdbarch_data);
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return (TYPE_FIELD_BITPOS (vtable_type, vtable_field_virtual_functions)
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/ TARGET_CHAR_BIT);
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}
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/* Determine whether structure TYPE is a dynamic class. Cache the
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result. */
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static int
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gnuv3_dynamic_class (struct type *type)
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{
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int fieldnum, fieldelem;
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CHECK_TYPEDEF (type);
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gdb_assert (TYPE_CODE (type) == TYPE_CODE_STRUCT
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|| TYPE_CODE (type) == TYPE_CODE_UNION);
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if (TYPE_CODE (type) == TYPE_CODE_UNION)
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return 0;
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if (TYPE_CPLUS_DYNAMIC (type))
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return TYPE_CPLUS_DYNAMIC (type) == 1;
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ALLOCATE_CPLUS_STRUCT_TYPE (type);
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for (fieldnum = 0; fieldnum < TYPE_N_BASECLASSES (type); fieldnum++)
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if (BASETYPE_VIA_VIRTUAL (type, fieldnum)
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|| gnuv3_dynamic_class (TYPE_FIELD_TYPE (type, fieldnum)))
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{
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TYPE_CPLUS_DYNAMIC (type) = 1;
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return 1;
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}
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for (fieldnum = 0; fieldnum < TYPE_NFN_FIELDS (type); fieldnum++)
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for (fieldelem = 0; fieldelem < TYPE_FN_FIELDLIST_LENGTH (type, fieldnum);
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fieldelem++)
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{
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struct fn_field *f = TYPE_FN_FIELDLIST1 (type, fieldnum);
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if (TYPE_FN_FIELD_VIRTUAL_P (f, fieldelem))
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{
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TYPE_CPLUS_DYNAMIC (type) = 1;
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return 1;
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}
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}
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TYPE_CPLUS_DYNAMIC (type) = -1;
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return 0;
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}
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/* Find the vtable for a value of CONTAINER_TYPE located at
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CONTAINER_ADDR. Return a value of the correct vtable type for this
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architecture, or NULL if CONTAINER does not have a vtable. */
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static struct value *
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gnuv3_get_vtable (struct gdbarch *gdbarch,
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struct type *container_type, CORE_ADDR container_addr)
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{
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struct type *vtable_type = gdbarch_data (gdbarch,
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vtable_type_gdbarch_data);
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struct type *vtable_pointer_type;
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struct value *vtable_pointer;
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CORE_ADDR vtable_address;
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CHECK_TYPEDEF (container_type);
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gdb_assert (TYPE_CODE (container_type) == TYPE_CODE_STRUCT);
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/* If this type does not have a virtual table, don't read the first
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field. */
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if (!gnuv3_dynamic_class (container_type))
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return NULL;
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/* We do not consult the debug information to find the virtual table.
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The ABI specifies that it is always at offset zero in any class,
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and debug information may not represent it.
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We avoid using value_contents on principle, because the object might
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be large. */
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/* Find the type "pointer to virtual table". */
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vtable_pointer_type = lookup_pointer_type (vtable_type);
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/* Load it from the start of the class. */
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vtable_pointer = value_at (vtable_pointer_type, container_addr);
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vtable_address = value_as_address (vtable_pointer);
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/* Correct it to point at the start of the virtual table, rather
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than the address point. */
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return value_at_lazy (vtable_type,
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vtable_address
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- vtable_address_point_offset (gdbarch));
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}
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static struct type *
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gnuv3_rtti_type (struct value *value,
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int *full_p, int *top_p, int *using_enc_p)
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{
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struct gdbarch *gdbarch;
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struct type *values_type = check_typedef (value_type (value));
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struct value *vtable;
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struct minimal_symbol *vtable_symbol;
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const char *vtable_symbol_name;
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const char *class_name;
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struct type *run_time_type;
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LONGEST offset_to_top;
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char *atsign;
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/* We only have RTTI for class objects. */
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if (TYPE_CODE (values_type) != TYPE_CODE_STRUCT)
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return NULL;
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/* Java doesn't have RTTI following the C++ ABI. */
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if (TYPE_CPLUS_REALLY_JAVA (values_type))
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return NULL;
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/* Determine architecture. */
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gdbarch = get_type_arch (values_type);
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if (using_enc_p)
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*using_enc_p = 0;
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vtable = gnuv3_get_vtable (gdbarch, values_type,
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value_as_address (value_addr (value)));
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if (vtable == NULL)
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return NULL;
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/* Find the linker symbol for this vtable. */
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vtable_symbol
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= lookup_minimal_symbol_by_pc (value_address (vtable)
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+ value_embedded_offset (vtable)).minsym;
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if (! vtable_symbol)
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return NULL;
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/* The symbol's demangled name should be something like "vtable for
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CLASS", where CLASS is the name of the run-time type of VALUE.
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If we didn't like this approach, we could instead look in the
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type_info object itself to get the class name. But this way
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should work just as well, and doesn't read target memory. */
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vtable_symbol_name = MSYMBOL_DEMANGLED_NAME (vtable_symbol);
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if (vtable_symbol_name == NULL
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|| !startswith (vtable_symbol_name, "vtable for "))
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{
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warning (_("can't find linker symbol for virtual table for `%s' value"),
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TYPE_SAFE_NAME (values_type));
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if (vtable_symbol_name)
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warning (_(" found `%s' instead"), vtable_symbol_name);
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return NULL;
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}
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class_name = vtable_symbol_name + 11;
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/* Strip off @plt and version suffixes. */
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atsign = strchr (class_name, '@');
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if (atsign != NULL)
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{
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char *copy;
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copy = alloca (atsign - class_name + 1);
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memcpy (copy, class_name, atsign - class_name);
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copy[atsign - class_name] = '\0';
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class_name = copy;
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}
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/* Try to look up the class name as a type name. */
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/* FIXME: chastain/2003-11-26: block=NULL is bogus. See pr gdb/1465. */
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run_time_type = cp_lookup_rtti_type (class_name, NULL);
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if (run_time_type == NULL)
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return NULL;
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/* Get the offset from VALUE to the top of the complete object.
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NOTE: this is the reverse of the meaning of *TOP_P. */
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offset_to_top
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= value_as_long (value_field (vtable, vtable_field_offset_to_top));
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if (full_p)
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*full_p = (- offset_to_top == value_embedded_offset (value)
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&& (TYPE_LENGTH (value_enclosing_type (value))
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>= TYPE_LENGTH (run_time_type)));
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if (top_p)
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*top_p = - offset_to_top;
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return run_time_type;
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}
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/* Return a function pointer for CONTAINER's VTABLE_INDEX'th virtual
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function, of type FNTYPE. */
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static struct value *
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gnuv3_get_virtual_fn (struct gdbarch *gdbarch, struct value *container,
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struct type *fntype, int vtable_index)
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{
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struct value *vtable, *vfn;
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/* Every class with virtual functions must have a vtable. */
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vtable = gnuv3_get_vtable (gdbarch, value_type (container),
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value_as_address (value_addr (container)));
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gdb_assert (vtable != NULL);
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/* Fetch the appropriate function pointer from the vtable. */
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vfn = value_subscript (value_field (vtable, vtable_field_virtual_functions),
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vtable_index);
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/* If this architecture uses function descriptors directly in the vtable,
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then the address of the vtable entry is actually a "function pointer"
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(i.e. points to the descriptor). We don't need to scale the index
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by the size of a function descriptor; GCC does that before outputing
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debug information. */
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if (gdbarch_vtable_function_descriptors (gdbarch))
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vfn = value_addr (vfn);
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/* Cast the function pointer to the appropriate type. */
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vfn = value_cast (lookup_pointer_type (fntype), vfn);
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return vfn;
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}
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|
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/* GNU v3 implementation of value_virtual_fn_field. See cp-abi.h
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for a description of the arguments. */
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|
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static struct value *
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gnuv3_virtual_fn_field (struct value **value_p,
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struct fn_field *f, int j,
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struct type *vfn_base, int offset)
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{
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struct type *values_type = check_typedef (value_type (*value_p));
|
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struct gdbarch *gdbarch;
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|
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/* Some simple sanity checks. */
|
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if (TYPE_CODE (values_type) != TYPE_CODE_STRUCT)
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error (_("Only classes can have virtual functions."));
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|
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/* Determine architecture. */
|
|
gdbarch = get_type_arch (values_type);
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|
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/* Cast our value to the base class which defines this virtual
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function. This takes care of any necessary `this'
|
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adjustments. */
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if (vfn_base != values_type)
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*value_p = value_cast (vfn_base, *value_p);
|
|
|
|
return gnuv3_get_virtual_fn (gdbarch, *value_p, TYPE_FN_FIELD_TYPE (f, j),
|
|
TYPE_FN_FIELD_VOFFSET (f, j));
|
|
}
|
|
|
|
/* 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. */
|
|
|
|
static int
|
|
gnuv3_baseclass_offset (struct type *type, int index,
|
|
const bfd_byte *valaddr, int embedded_offset,
|
|
CORE_ADDR address, const struct value *val)
|
|
{
|
|
struct gdbarch *gdbarch;
|
|
struct type *ptr_type;
|
|
struct value *vtable;
|
|
struct value *vbase_array;
|
|
long int cur_base_offset, base_offset;
|
|
|
|
/* Determine architecture. */
|
|
gdbarch = get_type_arch (type);
|
|
ptr_type = builtin_type (gdbarch)->builtin_data_ptr;
|
|
|
|
/* If it isn't a virtual base, this is easy. The offset is in the
|
|
type definition. Likewise for Java, which doesn't really have
|
|
virtual inheritance in the C++ sense. */
|
|
if (!BASETYPE_VIA_VIRTUAL (type, index) || TYPE_CPLUS_REALLY_JAVA (type))
|
|
return TYPE_BASECLASS_BITPOS (type, index) / 8;
|
|
|
|
/* To access a virtual base, we need to use the vbase offset stored in
|
|
our vtable. Recent GCC versions provide this information. If it isn't
|
|
available, we could get what we needed from RTTI, or from drawing the
|
|
complete inheritance graph based on the debug info. Neither is
|
|
worthwhile. */
|
|
cur_base_offset = TYPE_BASECLASS_BITPOS (type, index) / 8;
|
|
if (cur_base_offset >= - vtable_address_point_offset (gdbarch))
|
|
error (_("Expected a negative vbase offset (old compiler?)"));
|
|
|
|
cur_base_offset = cur_base_offset + vtable_address_point_offset (gdbarch);
|
|
if ((- cur_base_offset) % TYPE_LENGTH (ptr_type) != 0)
|
|
error (_("Misaligned vbase offset."));
|
|
cur_base_offset = cur_base_offset / ((int) TYPE_LENGTH (ptr_type));
|
|
|
|
vtable = gnuv3_get_vtable (gdbarch, type, address + embedded_offset);
|
|
gdb_assert (vtable != NULL);
|
|
vbase_array = value_field (vtable, vtable_field_vcall_and_vbase_offsets);
|
|
base_offset = value_as_long (value_subscript (vbase_array, cur_base_offset));
|
|
return base_offset;
|
|
}
|
|
|
|
/* Locate a virtual method in DOMAIN or its non-virtual base classes
|
|
which has virtual table index VOFFSET. The method has an associated
|
|
"this" adjustment of ADJUSTMENT bytes. */
|
|
|
|
static const char *
|
|
gnuv3_find_method_in (struct type *domain, CORE_ADDR voffset,
|
|
LONGEST adjustment)
|
|
{
|
|
int i;
|
|
|
|
/* Search this class first. */
|
|
if (adjustment == 0)
|
|
{
|
|
int len;
|
|
|
|
len = TYPE_NFN_FIELDS (domain);
|
|
for (i = 0; i < len; i++)
|
|
{
|
|
int len2, j;
|
|
struct fn_field *f;
|
|
|
|
f = TYPE_FN_FIELDLIST1 (domain, i);
|
|
len2 = TYPE_FN_FIELDLIST_LENGTH (domain, i);
|
|
|
|
check_stub_method_group (domain, i);
|
|
for (j = 0; j < len2; j++)
|
|
if (TYPE_FN_FIELD_VOFFSET (f, j) == voffset)
|
|
return TYPE_FN_FIELD_PHYSNAME (f, j);
|
|
}
|
|
}
|
|
|
|
/* Next search non-virtual bases. If it's in a virtual base,
|
|
we're out of luck. */
|
|
for (i = 0; i < TYPE_N_BASECLASSES (domain); i++)
|
|
{
|
|
int pos;
|
|
struct type *basetype;
|
|
|
|
if (BASETYPE_VIA_VIRTUAL (domain, i))
|
|
continue;
|
|
|
|
pos = TYPE_BASECLASS_BITPOS (domain, i) / 8;
|
|
basetype = TYPE_FIELD_TYPE (domain, i);
|
|
/* Recurse with a modified adjustment. We don't need to adjust
|
|
voffset. */
|
|
if (adjustment >= pos && adjustment < pos + TYPE_LENGTH (basetype))
|
|
return gnuv3_find_method_in (basetype, voffset, adjustment - pos);
|
|
}
|
|
|
|
return NULL;
|
|
}
|
|
|
|
/* Decode GNU v3 method pointer. */
|
|
|
|
static int
|
|
gnuv3_decode_method_ptr (struct gdbarch *gdbarch,
|
|
const gdb_byte *contents,
|
|
CORE_ADDR *value_p,
|
|
LONGEST *adjustment_p)
|
|
{
|
|
struct type *funcptr_type = builtin_type (gdbarch)->builtin_func_ptr;
|
|
struct type *offset_type = vtable_ptrdiff_type (gdbarch);
|
|
enum bfd_endian byte_order = gdbarch_byte_order (gdbarch);
|
|
CORE_ADDR ptr_value;
|
|
LONGEST voffset, adjustment;
|
|
int vbit;
|
|
|
|
/* Extract the pointer to member. The first element is either a pointer
|
|
or a vtable offset. For pointers, we need to use extract_typed_address
|
|
to allow the back-end to convert the pointer to a GDB address -- but
|
|
vtable offsets we must handle as integers. At this point, we do not
|
|
yet know which case we have, so we extract the value under both
|
|
interpretations and choose the right one later on. */
|
|
ptr_value = extract_typed_address (contents, funcptr_type);
|
|
voffset = extract_signed_integer (contents,
|
|
TYPE_LENGTH (funcptr_type), byte_order);
|
|
contents += TYPE_LENGTH (funcptr_type);
|
|
adjustment = extract_signed_integer (contents,
|
|
TYPE_LENGTH (offset_type), byte_order);
|
|
|
|
if (!gdbarch_vbit_in_delta (gdbarch))
|
|
{
|
|
vbit = voffset & 1;
|
|
voffset = voffset ^ vbit;
|
|
}
|
|
else
|
|
{
|
|
vbit = adjustment & 1;
|
|
adjustment = adjustment >> 1;
|
|
}
|
|
|
|
*value_p = vbit? voffset : ptr_value;
|
|
*adjustment_p = adjustment;
|
|
return vbit;
|
|
}
|
|
|
|
/* GNU v3 implementation of cplus_print_method_ptr. */
|
|
|
|
static void
|
|
gnuv3_print_method_ptr (const gdb_byte *contents,
|
|
struct type *type,
|
|
struct ui_file *stream)
|
|
{
|
|
struct type *self_type = TYPE_SELF_TYPE (type);
|
|
struct gdbarch *gdbarch = get_type_arch (self_type);
|
|
CORE_ADDR ptr_value;
|
|
LONGEST adjustment;
|
|
int vbit;
|
|
|
|
/* Extract the pointer to member. */
|
|
vbit = gnuv3_decode_method_ptr (gdbarch, contents, &ptr_value, &adjustment);
|
|
|
|
/* Check for NULL. */
|
|
if (ptr_value == 0 && vbit == 0)
|
|
{
|
|
fprintf_filtered (stream, "NULL");
|
|
return;
|
|
}
|
|
|
|
/* Search for a virtual method. */
|
|
if (vbit)
|
|
{
|
|
CORE_ADDR voffset;
|
|
const char *physname;
|
|
|
|
/* It's a virtual table offset, maybe in this class. Search
|
|
for a field with the correct vtable offset. First convert it
|
|
to an index, as used in TYPE_FN_FIELD_VOFFSET. */
|
|
voffset = ptr_value / TYPE_LENGTH (vtable_ptrdiff_type (gdbarch));
|
|
|
|
physname = gnuv3_find_method_in (self_type, voffset, adjustment);
|
|
|
|
/* If we found a method, print that. We don't bother to disambiguate
|
|
possible paths to the method based on the adjustment. */
|
|
if (physname)
|
|
{
|
|
char *demangled_name = gdb_demangle (physname,
|
|
DMGL_ANSI | DMGL_PARAMS);
|
|
|
|
fprintf_filtered (stream, "&virtual ");
|
|
if (demangled_name == NULL)
|
|
fputs_filtered (physname, stream);
|
|
else
|
|
{
|
|
fputs_filtered (demangled_name, stream);
|
|
xfree (demangled_name);
|
|
}
|
|
return;
|
|
}
|
|
}
|
|
else if (ptr_value != 0)
|
|
{
|
|
/* Found a non-virtual function: print out the type. */
|
|
fputs_filtered ("(", stream);
|
|
c_print_type (type, "", stream, -1, 0, &type_print_raw_options);
|
|
fputs_filtered (") ", stream);
|
|
}
|
|
|
|
/* We didn't find it; print the raw data. */
|
|
if (vbit)
|
|
{
|
|
fprintf_filtered (stream, "&virtual table offset ");
|
|
print_longest (stream, 'd', 1, ptr_value);
|
|
}
|
|
else
|
|
{
|
|
struct value_print_options opts;
|
|
|
|
get_user_print_options (&opts);
|
|
print_address_demangle (&opts, gdbarch, ptr_value, stream, demangle);
|
|
}
|
|
|
|
if (adjustment)
|
|
{
|
|
fprintf_filtered (stream, ", this adjustment ");
|
|
print_longest (stream, 'd', 1, adjustment);
|
|
}
|
|
}
|
|
|
|
/* GNU v3 implementation of cplus_method_ptr_size. */
|
|
|
|
static int
|
|
gnuv3_method_ptr_size (struct type *type)
|
|
{
|
|
struct gdbarch *gdbarch = get_type_arch (type);
|
|
|
|
return 2 * TYPE_LENGTH (builtin_type (gdbarch)->builtin_data_ptr);
|
|
}
|
|
|
|
/* GNU v3 implementation of cplus_make_method_ptr. */
|
|
|
|
static void
|
|
gnuv3_make_method_ptr (struct type *type, gdb_byte *contents,
|
|
CORE_ADDR value, int is_virtual)
|
|
{
|
|
struct gdbarch *gdbarch = get_type_arch (type);
|
|
int size = TYPE_LENGTH (builtin_type (gdbarch)->builtin_data_ptr);
|
|
enum bfd_endian byte_order = gdbarch_byte_order (gdbarch);
|
|
|
|
/* FIXME drow/2006-12-24: The adjustment of "this" is currently
|
|
always zero, since the method pointer is of the correct type.
|
|
But if the method pointer came from a base class, this is
|
|
incorrect - it should be the offset to the base. The best
|
|
fix might be to create the pointer to member pointing at the
|
|
base class and cast it to the derived class, but that requires
|
|
support for adjusting pointers to members when casting them -
|
|
not currently supported by GDB. */
|
|
|
|
if (!gdbarch_vbit_in_delta (gdbarch))
|
|
{
|
|
store_unsigned_integer (contents, size, byte_order, value | is_virtual);
|
|
store_unsigned_integer (contents + size, size, byte_order, 0);
|
|
}
|
|
else
|
|
{
|
|
store_unsigned_integer (contents, size, byte_order, value);
|
|
store_unsigned_integer (contents + size, size, byte_order, is_virtual);
|
|
}
|
|
}
|
|
|
|
/* GNU v3 implementation of cplus_method_ptr_to_value. */
|
|
|
|
static struct value *
|
|
gnuv3_method_ptr_to_value (struct value **this_p, struct value *method_ptr)
|
|
{
|
|
struct gdbarch *gdbarch;
|
|
const gdb_byte *contents = value_contents (method_ptr);
|
|
CORE_ADDR ptr_value;
|
|
struct type *self_type, *final_type, *method_type;
|
|
LONGEST adjustment;
|
|
int vbit;
|
|
|
|
self_type = TYPE_SELF_TYPE (check_typedef (value_type (method_ptr)));
|
|
final_type = lookup_pointer_type (self_type);
|
|
|
|
method_type = TYPE_TARGET_TYPE (check_typedef (value_type (method_ptr)));
|
|
|
|
/* Extract the pointer to member. */
|
|
gdbarch = get_type_arch (self_type);
|
|
vbit = gnuv3_decode_method_ptr (gdbarch, contents, &ptr_value, &adjustment);
|
|
|
|
/* First convert THIS to match the containing type of the pointer to
|
|
member. This cast may adjust the value of THIS. */
|
|
*this_p = value_cast (final_type, *this_p);
|
|
|
|
/* Then apply whatever adjustment is necessary. This creates a somewhat
|
|
strange pointer: it claims to have type FINAL_TYPE, but in fact it
|
|
might not be a valid FINAL_TYPE. For instance, it might be a
|
|
base class of FINAL_TYPE. And if it's not the primary base class,
|
|
then printing it out as a FINAL_TYPE object would produce some pretty
|
|
garbage.
|
|
|
|
But we don't really know the type of the first argument in
|
|
METHOD_TYPE either, which is why this happens. We can't
|
|
dereference this later as a FINAL_TYPE, but once we arrive in the
|
|
called method we'll have debugging information for the type of
|
|
"this" - and that'll match the value we produce here.
|
|
|
|
You can provoke this case by casting a Base::* to a Derived::*, for
|
|
instance. */
|
|
*this_p = value_cast (builtin_type (gdbarch)->builtin_data_ptr, *this_p);
|
|
*this_p = value_ptradd (*this_p, adjustment);
|
|
*this_p = value_cast (final_type, *this_p);
|
|
|
|
if (vbit)
|
|
{
|
|
LONGEST voffset;
|
|
|
|
voffset = ptr_value / TYPE_LENGTH (vtable_ptrdiff_type (gdbarch));
|
|
return gnuv3_get_virtual_fn (gdbarch, value_ind (*this_p),
|
|
method_type, voffset);
|
|
}
|
|
else
|
|
return value_from_pointer (lookup_pointer_type (method_type), ptr_value);
|
|
}
|
|
|
|
/* Objects of this type are stored in a hash table and a vector when
|
|
printing the vtables for a class. */
|
|
|
|
struct value_and_voffset
|
|
{
|
|
/* The value representing the object. */
|
|
struct value *value;
|
|
|
|
/* The maximum vtable offset we've found for any object at this
|
|
offset in the outermost object. */
|
|
int max_voffset;
|
|
};
|
|
|
|
typedef struct value_and_voffset *value_and_voffset_p;
|
|
DEF_VEC_P (value_and_voffset_p);
|
|
|
|
/* Hash function for value_and_voffset. */
|
|
|
|
static hashval_t
|
|
hash_value_and_voffset (const void *p)
|
|
{
|
|
const struct value_and_voffset *o = p;
|
|
|
|
return value_address (o->value) + value_embedded_offset (o->value);
|
|
}
|
|
|
|
/* Equality function for value_and_voffset. */
|
|
|
|
static int
|
|
eq_value_and_voffset (const void *a, const void *b)
|
|
{
|
|
const struct value_and_voffset *ova = a;
|
|
const struct value_and_voffset *ovb = b;
|
|
|
|
return (value_address (ova->value) + value_embedded_offset (ova->value)
|
|
== value_address (ovb->value) + value_embedded_offset (ovb->value));
|
|
}
|
|
|
|
/* qsort comparison function for value_and_voffset. */
|
|
|
|
static int
|
|
compare_value_and_voffset (const void *a, const void *b)
|
|
{
|
|
const struct value_and_voffset * const *ova = a;
|
|
CORE_ADDR addra = (value_address ((*ova)->value)
|
|
+ value_embedded_offset ((*ova)->value));
|
|
const struct value_and_voffset * const *ovb = b;
|
|
CORE_ADDR addrb = (value_address ((*ovb)->value)
|
|
+ value_embedded_offset ((*ovb)->value));
|
|
|
|
if (addra < addrb)
|
|
return -1;
|
|
if (addra > addrb)
|
|
return 1;
|
|
return 0;
|
|
}
|
|
|
|
/* A helper function used when printing vtables. This determines the
|
|
key (most derived) sub-object at each address and also computes the
|
|
maximum vtable offset seen for the corresponding vtable. Updates
|
|
OFFSET_HASH and OFFSET_VEC with a new value_and_voffset object, if
|
|
needed. VALUE is the object to examine. */
|
|
|
|
static void
|
|
compute_vtable_size (htab_t offset_hash,
|
|
VEC (value_and_voffset_p) **offset_vec,
|
|
struct value *value)
|
|
{
|
|
int i;
|
|
struct type *type = check_typedef (value_type (value));
|
|
void **slot;
|
|
struct value_and_voffset search_vo, *current_vo;
|
|
|
|
gdb_assert (TYPE_CODE (type) == TYPE_CODE_STRUCT);
|
|
|
|
/* If the object is not dynamic, then we are done; as it cannot have
|
|
dynamic base types either. */
|
|
if (!gnuv3_dynamic_class (type))
|
|
return;
|
|
|
|
/* Update the hash and the vec, if needed. */
|
|
search_vo.value = value;
|
|
slot = htab_find_slot (offset_hash, &search_vo, INSERT);
|
|
if (*slot)
|
|
current_vo = *slot;
|
|
else
|
|
{
|
|
current_vo = XNEW (struct value_and_voffset);
|
|
current_vo->value = value;
|
|
current_vo->max_voffset = -1;
|
|
*slot = current_vo;
|
|
VEC_safe_push (value_and_voffset_p, *offset_vec, current_vo);
|
|
}
|
|
|
|
/* Update the value_and_voffset object with the highest vtable
|
|
offset from this class. */
|
|
for (i = 0; i < TYPE_NFN_FIELDS (type); ++i)
|
|
{
|
|
int j;
|
|
struct fn_field *fn = TYPE_FN_FIELDLIST1 (type, i);
|
|
|
|
for (j = 0; j < TYPE_FN_FIELDLIST_LENGTH (type, i); ++j)
|
|
{
|
|
if (TYPE_FN_FIELD_VIRTUAL_P (fn, j))
|
|
{
|
|
int voffset = TYPE_FN_FIELD_VOFFSET (fn, j);
|
|
|
|
if (voffset > current_vo->max_voffset)
|
|
current_vo->max_voffset = voffset;
|
|
}
|
|
}
|
|
}
|
|
|
|
/* Recurse into base classes. */
|
|
for (i = 0; i < TYPE_N_BASECLASSES (type); ++i)
|
|
compute_vtable_size (offset_hash, offset_vec, value_field (value, i));
|
|
}
|
|
|
|
/* Helper for gnuv3_print_vtable that prints a single vtable. */
|
|
|
|
static void
|
|
print_one_vtable (struct gdbarch *gdbarch, struct value *value,
|
|
int max_voffset,
|
|
struct value_print_options *opts)
|
|
{
|
|
int i;
|
|
struct type *type = check_typedef (value_type (value));
|
|
struct value *vtable;
|
|
CORE_ADDR vt_addr;
|
|
|
|
vtable = gnuv3_get_vtable (gdbarch, type,
|
|
value_address (value)
|
|
+ value_embedded_offset (value));
|
|
vt_addr = value_address (value_field (vtable,
|
|
vtable_field_virtual_functions));
|
|
|
|
printf_filtered (_("vtable for '%s' @ %s (subobject @ %s):\n"),
|
|
TYPE_SAFE_NAME (type),
|
|
paddress (gdbarch, vt_addr),
|
|
paddress (gdbarch, (value_address (value)
|
|
+ value_embedded_offset (value))));
|
|
|
|
for (i = 0; i <= max_voffset; ++i)
|
|
{
|
|
/* Initialize it just to avoid a GCC false warning. */
|
|
CORE_ADDR addr = 0;
|
|
int got_error = 0;
|
|
struct value *vfn;
|
|
|
|
printf_filtered ("[%d]: ", i);
|
|
|
|
vfn = value_subscript (value_field (vtable,
|
|
vtable_field_virtual_functions),
|
|
i);
|
|
|
|
if (gdbarch_vtable_function_descriptors (gdbarch))
|
|
vfn = value_addr (vfn);
|
|
|
|
TRY
|
|
{
|
|
addr = value_as_address (vfn);
|
|
}
|
|
CATCH (ex, RETURN_MASK_ERROR)
|
|
{
|
|
printf_filtered (_("<error: %s>"), ex.message);
|
|
got_error = 1;
|
|
}
|
|
END_CATCH
|
|
|
|
if (!got_error)
|
|
print_function_pointer_address (opts, gdbarch, addr, gdb_stdout);
|
|
printf_filtered ("\n");
|
|
}
|
|
}
|
|
|
|
/* Implementation of the print_vtable method. */
|
|
|
|
static void
|
|
gnuv3_print_vtable (struct value *value)
|
|
{
|
|
struct gdbarch *gdbarch;
|
|
struct type *type;
|
|
struct value *vtable;
|
|
struct value_print_options opts;
|
|
htab_t offset_hash;
|
|
struct cleanup *cleanup;
|
|
VEC (value_and_voffset_p) *result_vec = NULL;
|
|
struct value_and_voffset *iter;
|
|
int i, count;
|
|
|
|
value = coerce_ref (value);
|
|
type = check_typedef (value_type (value));
|
|
if (TYPE_CODE (type) == TYPE_CODE_PTR)
|
|
{
|
|
value = value_ind (value);
|
|
type = check_typedef (value_type (value));
|
|
}
|
|
|
|
get_user_print_options (&opts);
|
|
|
|
/* Respect 'set print object'. */
|
|
if (opts.objectprint)
|
|
{
|
|
value = value_full_object (value, NULL, 0, 0, 0);
|
|
type = check_typedef (value_type (value));
|
|
}
|
|
|
|
gdbarch = get_type_arch (type);
|
|
|
|
vtable = NULL;
|
|
if (TYPE_CODE (type) == TYPE_CODE_STRUCT)
|
|
vtable = gnuv3_get_vtable (gdbarch, type,
|
|
value_as_address (value_addr (value)));
|
|
|
|
if (!vtable)
|
|
{
|
|
printf_filtered (_("This object does not have a virtual function table\n"));
|
|
return;
|
|
}
|
|
|
|
offset_hash = htab_create_alloc (1, hash_value_and_voffset,
|
|
eq_value_and_voffset,
|
|
xfree, xcalloc, xfree);
|
|
cleanup = make_cleanup_htab_delete (offset_hash);
|
|
make_cleanup (VEC_cleanup (value_and_voffset_p), &result_vec);
|
|
|
|
compute_vtable_size (offset_hash, &result_vec, value);
|
|
|
|
qsort (VEC_address (value_and_voffset_p, result_vec),
|
|
VEC_length (value_and_voffset_p, result_vec),
|
|
sizeof (value_and_voffset_p),
|
|
compare_value_and_voffset);
|
|
|
|
count = 0;
|
|
for (i = 0; VEC_iterate (value_and_voffset_p, result_vec, i, iter); ++i)
|
|
{
|
|
if (iter->max_voffset >= 0)
|
|
{
|
|
if (count > 0)
|
|
printf_filtered ("\n");
|
|
print_one_vtable (gdbarch, iter->value, iter->max_voffset, &opts);
|
|
++count;
|
|
}
|
|
}
|
|
|
|
do_cleanups (cleanup);
|
|
}
|
|
|
|
/* Return a GDB type representing `struct std::type_info', laid out
|
|
appropriately for ARCH.
|
|
|
|
We use this function as the gdbarch per-architecture data
|
|
initialization function. */
|
|
|
|
static void *
|
|
build_std_type_info_type (struct gdbarch *arch)
|
|
{
|
|
struct type *t;
|
|
struct field *field_list, *field;
|
|
int offset;
|
|
struct type *void_ptr_type
|
|
= builtin_type (arch)->builtin_data_ptr;
|
|
struct type *char_type
|
|
= builtin_type (arch)->builtin_char;
|
|
struct type *char_ptr_type
|
|
= make_pointer_type (make_cv_type (1, 0, char_type, NULL), NULL);
|
|
|
|
field_list = xmalloc (sizeof (struct field [2]));
|
|
memset (field_list, 0, sizeof (struct field [2]));
|
|
field = &field_list[0];
|
|
offset = 0;
|
|
|
|
/* The vtable. */
|
|
FIELD_NAME (*field) = "_vptr.type_info";
|
|
FIELD_TYPE (*field) = void_ptr_type;
|
|
SET_FIELD_BITPOS (*field, offset * TARGET_CHAR_BIT);
|
|
offset += TYPE_LENGTH (FIELD_TYPE (*field));
|
|
field++;
|
|
|
|
/* The name. */
|
|
FIELD_NAME (*field) = "__name";
|
|
FIELD_TYPE (*field) = char_ptr_type;
|
|
SET_FIELD_BITPOS (*field, offset * TARGET_CHAR_BIT);
|
|
offset += TYPE_LENGTH (FIELD_TYPE (*field));
|
|
field++;
|
|
|
|
gdb_assert (field == (field_list + 2));
|
|
|
|
t = arch_type (arch, TYPE_CODE_STRUCT, offset, NULL);
|
|
TYPE_NFIELDS (t) = field - field_list;
|
|
TYPE_FIELDS (t) = field_list;
|
|
TYPE_TAG_NAME (t) = "gdb_gnu_v3_type_info";
|
|
INIT_CPLUS_SPECIFIC (t);
|
|
|
|
return t;
|
|
}
|
|
|
|
/* Implement the 'get_typeid_type' method. */
|
|
|
|
static struct type *
|
|
gnuv3_get_typeid_type (struct gdbarch *gdbarch)
|
|
{
|
|
struct symbol *typeinfo;
|
|
struct type *typeinfo_type;
|
|
|
|
typeinfo = lookup_symbol ("std::type_info", NULL, STRUCT_DOMAIN, NULL);
|
|
if (typeinfo == NULL)
|
|
typeinfo_type = gdbarch_data (gdbarch, std_type_info_gdbarch_data);
|
|
else
|
|
typeinfo_type = SYMBOL_TYPE (typeinfo);
|
|
|
|
return typeinfo_type;
|
|
}
|
|
|
|
/* Implement the 'get_typeid' method. */
|
|
|
|
static struct value *
|
|
gnuv3_get_typeid (struct value *value)
|
|
{
|
|
struct type *typeinfo_type;
|
|
struct type *type;
|
|
struct gdbarch *gdbarch;
|
|
struct cleanup *cleanup;
|
|
struct value *result;
|
|
char *type_name, *canonical;
|
|
|
|
/* We have to handle values a bit trickily here, to allow this code
|
|
to work properly with non_lvalue values that are really just
|
|
disguised types. */
|
|
if (value_lval_const (value) == lval_memory)
|
|
value = coerce_ref (value);
|
|
|
|
type = check_typedef (value_type (value));
|
|
|
|
/* In the non_lvalue case, a reference might have slipped through
|
|
here. */
|
|
if (TYPE_CODE (type) == TYPE_CODE_REF)
|
|
type = check_typedef (TYPE_TARGET_TYPE (type));
|
|
|
|
/* Ignore top-level cv-qualifiers. */
|
|
type = make_cv_type (0, 0, type, NULL);
|
|
gdbarch = get_type_arch (type);
|
|
|
|
type_name = type_to_string (type);
|
|
if (type_name == NULL)
|
|
error (_("cannot find typeinfo for unnamed type"));
|
|
cleanup = make_cleanup (xfree, type_name);
|
|
|
|
/* We need to canonicalize the type name here, because we do lookups
|
|
using the demangled name, and so we must match the format it
|
|
uses. E.g., GDB tends to use "const char *" as a type name, but
|
|
the demangler uses "char const *". */
|
|
canonical = cp_canonicalize_string (type_name);
|
|
if (canonical != NULL)
|
|
{
|
|
make_cleanup (xfree, canonical);
|
|
type_name = canonical;
|
|
}
|
|
|
|
typeinfo_type = gnuv3_get_typeid_type (gdbarch);
|
|
|
|
/* We check for lval_memory because in the "typeid (type-id)" case,
|
|
the type is passed via a not_lval value object. */
|
|
if (TYPE_CODE (type) == TYPE_CODE_STRUCT
|
|
&& value_lval_const (value) == lval_memory
|
|
&& gnuv3_dynamic_class (type))
|
|
{
|
|
struct value *vtable, *typeinfo_value;
|
|
CORE_ADDR address = value_address (value) + value_embedded_offset (value);
|
|
|
|
vtable = gnuv3_get_vtable (gdbarch, type, address);
|
|
if (vtable == NULL)
|
|
error (_("cannot find typeinfo for object of type '%s'"), type_name);
|
|
typeinfo_value = value_field (vtable, vtable_field_type_info);
|
|
result = value_ind (value_cast (make_pointer_type (typeinfo_type, NULL),
|
|
typeinfo_value));
|
|
}
|
|
else
|
|
{
|
|
char *sym_name;
|
|
struct bound_minimal_symbol minsym;
|
|
|
|
sym_name = concat ("typeinfo for ", type_name, (char *) NULL);
|
|
make_cleanup (xfree, sym_name);
|
|
minsym = lookup_minimal_symbol (sym_name, NULL, NULL);
|
|
|
|
if (minsym.minsym == NULL)
|
|
error (_("could not find typeinfo symbol for '%s'"), type_name);
|
|
|
|
result = value_at_lazy (typeinfo_type, BMSYMBOL_VALUE_ADDRESS (minsym));
|
|
}
|
|
|
|
do_cleanups (cleanup);
|
|
return result;
|
|
}
|
|
|
|
/* Implement the 'get_typename_from_type_info' method. */
|
|
|
|
static char *
|
|
gnuv3_get_typename_from_type_info (struct value *type_info_ptr)
|
|
{
|
|
struct gdbarch *gdbarch = get_type_arch (value_type (type_info_ptr));
|
|
struct bound_minimal_symbol typeinfo_sym;
|
|
CORE_ADDR addr;
|
|
const char *symname;
|
|
const char *class_name;
|
|
const char *atsign;
|
|
|
|
addr = value_as_address (type_info_ptr);
|
|
typeinfo_sym = lookup_minimal_symbol_by_pc (addr);
|
|
if (typeinfo_sym.minsym == NULL)
|
|
error (_("could not find minimal symbol for typeinfo address %s"),
|
|
paddress (gdbarch, addr));
|
|
|
|
#define TYPEINFO_PREFIX "typeinfo for "
|
|
#define TYPEINFO_PREFIX_LEN (sizeof (TYPEINFO_PREFIX) - 1)
|
|
symname = MSYMBOL_DEMANGLED_NAME (typeinfo_sym.minsym);
|
|
if (symname == NULL || strncmp (symname, TYPEINFO_PREFIX,
|
|
TYPEINFO_PREFIX_LEN))
|
|
error (_("typeinfo symbol '%s' has unexpected name"),
|
|
MSYMBOL_LINKAGE_NAME (typeinfo_sym.minsym));
|
|
class_name = symname + TYPEINFO_PREFIX_LEN;
|
|
|
|
/* Strip off @plt and version suffixes. */
|
|
atsign = strchr (class_name, '@');
|
|
if (atsign != NULL)
|
|
return savestring (class_name, atsign - class_name);
|
|
return xstrdup (class_name);
|
|
}
|
|
|
|
/* Implement the 'get_type_from_type_info' method. */
|
|
|
|
static struct type *
|
|
gnuv3_get_type_from_type_info (struct value *type_info_ptr)
|
|
{
|
|
char *type_name;
|
|
struct cleanup *cleanup;
|
|
struct value *type_val;
|
|
struct expression *expr;
|
|
struct type *result;
|
|
|
|
type_name = gnuv3_get_typename_from_type_info (type_info_ptr);
|
|
cleanup = make_cleanup (xfree, type_name);
|
|
|
|
/* We have to parse the type name, since in general there is not a
|
|
symbol for a type. This is somewhat bogus since there may be a
|
|
mis-parse. Another approach might be to re-use the demangler's
|
|
internal form to reconstruct the type somehow. */
|
|
|
|
expr = parse_expression (type_name);
|
|
make_cleanup (xfree, expr);
|
|
|
|
type_val = evaluate_type (expr);
|
|
result = value_type (type_val);
|
|
|
|
do_cleanups (cleanup);
|
|
return result;
|
|
}
|
|
|
|
/* Determine if we are currently in a C++ thunk. If so, get the address
|
|
of the routine we are thunking to and continue to there instead. */
|
|
|
|
static CORE_ADDR
|
|
gnuv3_skip_trampoline (struct frame_info *frame, CORE_ADDR stop_pc)
|
|
{
|
|
CORE_ADDR real_stop_pc, method_stop_pc, func_addr;
|
|
struct gdbarch *gdbarch = get_frame_arch (frame);
|
|
struct bound_minimal_symbol thunk_sym, fn_sym;
|
|
struct obj_section *section;
|
|
const char *thunk_name, *fn_name;
|
|
|
|
real_stop_pc = gdbarch_skip_trampoline_code (gdbarch, frame, stop_pc);
|
|
if (real_stop_pc == 0)
|
|
real_stop_pc = stop_pc;
|
|
|
|
/* Find the linker symbol for this potential thunk. */
|
|
thunk_sym = lookup_minimal_symbol_by_pc (real_stop_pc);
|
|
section = find_pc_section (real_stop_pc);
|
|
if (thunk_sym.minsym == NULL || section == NULL)
|
|
return 0;
|
|
|
|
/* The symbol's demangled name should be something like "virtual
|
|
thunk to FUNCTION", where FUNCTION is the name of the function
|
|
being thunked to. */
|
|
thunk_name = MSYMBOL_DEMANGLED_NAME (thunk_sym.minsym);
|
|
if (thunk_name == NULL || strstr (thunk_name, " thunk to ") == NULL)
|
|
return 0;
|
|
|
|
fn_name = strstr (thunk_name, " thunk to ") + strlen (" thunk to ");
|
|
fn_sym = lookup_minimal_symbol (fn_name, NULL, section->objfile);
|
|
if (fn_sym.minsym == NULL)
|
|
return 0;
|
|
|
|
method_stop_pc = BMSYMBOL_VALUE_ADDRESS (fn_sym);
|
|
|
|
/* Some targets have minimal symbols pointing to function descriptors
|
|
(powerpc 64 for example). Make sure to retrieve the address
|
|
of the real function from the function descriptor before passing on
|
|
the address to other layers of GDB. */
|
|
func_addr = gdbarch_convert_from_func_ptr_addr (gdbarch, method_stop_pc,
|
|
¤t_target);
|
|
if (func_addr != 0)
|
|
method_stop_pc = func_addr;
|
|
|
|
real_stop_pc = gdbarch_skip_trampoline_code
|
|
(gdbarch, frame, method_stop_pc);
|
|
if (real_stop_pc == 0)
|
|
real_stop_pc = method_stop_pc;
|
|
|
|
return real_stop_pc;
|
|
}
|
|
|
|
/* Return nonzero if a type should be passed by reference.
|
|
|
|
The rule in the v3 ABI document comes from section 3.1.1. If the
|
|
type has a non-trivial copy constructor or destructor, then the
|
|
caller must make a copy (by calling the copy constructor if there
|
|
is one or perform the copy itself otherwise), pass the address of
|
|
the copy, and then destroy the temporary (if necessary).
|
|
|
|
For return values with non-trivial copy constructors or
|
|
destructors, space will be allocated in the caller, and a pointer
|
|
will be passed as the first argument (preceding "this").
|
|
|
|
We don't have a bulletproof mechanism for determining whether a
|
|
constructor or destructor is trivial. For GCC and DWARF2 debug
|
|
information, we can check the artificial flag.
|
|
|
|
We don't do anything with the constructors or destructors,
|
|
but we have to get the argument passing right anyway. */
|
|
static int
|
|
gnuv3_pass_by_reference (struct type *type)
|
|
{
|
|
int fieldnum, fieldelem;
|
|
|
|
CHECK_TYPEDEF (type);
|
|
|
|
/* We're only interested in things that can have methods. */
|
|
if (TYPE_CODE (type) != TYPE_CODE_STRUCT
|
|
&& TYPE_CODE (type) != TYPE_CODE_UNION)
|
|
return 0;
|
|
|
|
/* A dynamic class has a non-trivial copy constructor.
|
|
See c++98 section 12.8 Copying class objects [class.copy]. */
|
|
if (gnuv3_dynamic_class (type))
|
|
return 1;
|
|
|
|
for (fieldnum = 0; fieldnum < TYPE_NFN_FIELDS (type); fieldnum++)
|
|
for (fieldelem = 0; fieldelem < TYPE_FN_FIELDLIST_LENGTH (type, fieldnum);
|
|
fieldelem++)
|
|
{
|
|
struct fn_field *fn = TYPE_FN_FIELDLIST1 (type, fieldnum);
|
|
const char *name = TYPE_FN_FIELDLIST_NAME (type, fieldnum);
|
|
struct type *fieldtype = TYPE_FN_FIELD_TYPE (fn, fieldelem);
|
|
|
|
/* If this function is marked as artificial, it is compiler-generated,
|
|
and we assume it is trivial. */
|
|
if (TYPE_FN_FIELD_ARTIFICIAL (fn, fieldelem))
|
|
continue;
|
|
|
|
/* If we've found a destructor, we must pass this by reference. */
|
|
if (name[0] == '~')
|
|
return 1;
|
|
|
|
/* If the mangled name of this method doesn't indicate that it
|
|
is a constructor, we're not interested.
|
|
|
|
FIXME drow/2007-09-23: We could do this using the name of
|
|
the method and the name of the class instead of dealing
|
|
with the mangled name. We don't have a convenient function
|
|
to strip off both leading scope qualifiers and trailing
|
|
template arguments yet. */
|
|
if (!is_constructor_name (TYPE_FN_FIELD_PHYSNAME (fn, fieldelem))
|
|
&& !TYPE_FN_FIELD_CONSTRUCTOR (fn, fieldelem))
|
|
continue;
|
|
|
|
/* If this method takes two arguments, and the second argument is
|
|
a reference to this class, then it is a copy constructor. */
|
|
if (TYPE_NFIELDS (fieldtype) == 2)
|
|
{
|
|
struct type *arg_type = TYPE_FIELD_TYPE (fieldtype, 1);
|
|
|
|
if (TYPE_CODE (arg_type) == TYPE_CODE_REF)
|
|
{
|
|
struct type *arg_target_type;
|
|
|
|
arg_target_type = check_typedef (TYPE_TARGET_TYPE (arg_type));
|
|
if (class_types_same_p (arg_target_type, type))
|
|
return 1;
|
|
}
|
|
}
|
|
}
|
|
|
|
/* Even if all the constructors and destructors were artificial, one
|
|
of them may have invoked a non-artificial constructor or
|
|
destructor in a base class. If any base class needs to be passed
|
|
by reference, so does this class. Similarly for members, which
|
|
are constructed whenever this class is. We do not need to worry
|
|
about recursive loops here, since we are only looking at members
|
|
of complete class type. Also ignore any static members. */
|
|
for (fieldnum = 0; fieldnum < TYPE_NFIELDS (type); fieldnum++)
|
|
if (! field_is_static (&TYPE_FIELD (type, fieldnum))
|
|
&& gnuv3_pass_by_reference (TYPE_FIELD_TYPE (type, fieldnum)))
|
|
return 1;
|
|
|
|
return 0;
|
|
}
|
|
|
|
static void
|
|
init_gnuv3_ops (void)
|
|
{
|
|
vtable_type_gdbarch_data
|
|
= gdbarch_data_register_post_init (build_gdb_vtable_type);
|
|
std_type_info_gdbarch_data
|
|
= gdbarch_data_register_post_init (build_std_type_info_type);
|
|
|
|
gnu_v3_abi_ops.shortname = "gnu-v3";
|
|
gnu_v3_abi_ops.longname = "GNU G++ Version 3 ABI";
|
|
gnu_v3_abi_ops.doc = "G++ Version 3 ABI";
|
|
gnu_v3_abi_ops.is_destructor_name =
|
|
(enum dtor_kinds (*) (const char *))is_gnu_v3_mangled_dtor;
|
|
gnu_v3_abi_ops.is_constructor_name =
|
|
(enum ctor_kinds (*) (const char *))is_gnu_v3_mangled_ctor;
|
|
gnu_v3_abi_ops.is_vtable_name = gnuv3_is_vtable_name;
|
|
gnu_v3_abi_ops.is_operator_name = gnuv3_is_operator_name;
|
|
gnu_v3_abi_ops.rtti_type = gnuv3_rtti_type;
|
|
gnu_v3_abi_ops.virtual_fn_field = gnuv3_virtual_fn_field;
|
|
gnu_v3_abi_ops.baseclass_offset = gnuv3_baseclass_offset;
|
|
gnu_v3_abi_ops.print_method_ptr = gnuv3_print_method_ptr;
|
|
gnu_v3_abi_ops.method_ptr_size = gnuv3_method_ptr_size;
|
|
gnu_v3_abi_ops.make_method_ptr = gnuv3_make_method_ptr;
|
|
gnu_v3_abi_ops.method_ptr_to_value = gnuv3_method_ptr_to_value;
|
|
gnu_v3_abi_ops.print_vtable = gnuv3_print_vtable;
|
|
gnu_v3_abi_ops.get_typeid = gnuv3_get_typeid;
|
|
gnu_v3_abi_ops.get_typeid_type = gnuv3_get_typeid_type;
|
|
gnu_v3_abi_ops.get_type_from_type_info = gnuv3_get_type_from_type_info;
|
|
gnu_v3_abi_ops.get_typename_from_type_info
|
|
= gnuv3_get_typename_from_type_info;
|
|
gnu_v3_abi_ops.skip_trampoline = gnuv3_skip_trampoline;
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gnu_v3_abi_ops.pass_by_reference = gnuv3_pass_by_reference;
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}
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extern initialize_file_ftype _initialize_gnu_v3_abi; /* -Wmissing-prototypes */
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void
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_initialize_gnu_v3_abi (void)
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{
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init_gnuv3_ops ();
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register_cp_abi (&gnu_v3_abi_ops);
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set_cp_abi_as_auto_default (gnu_v3_abi_ops.shortname);
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}
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