Files
binutils-gdb/gdb/compile/compile-object-run.c
Pedro Alves 7556d4a4f6 Normalize TRY_CATCH exception handling block
This normalizes some exception catch blocks that check for ex.reason
to look like this:

~~~
  volatile gdb_exception ex;

  TRY_CATCH (ex, RETURN_MASK_ALL)
    {
      ...
    }
  if (ex.reason < 0)
    {
      ...
    }
~~~

This is a preparation step for running a script that converts all
TRY_CATCH uses to look like this instead:

~~~
  TRY
    {
      ...
    }
  CATCH (ex, RETURN_MASK_ALL)
    {
      ...
    }
  END_CATCH
~~~

The motivation for that change is being able to reimplent TRY/CATCH in
terms of C++ try/catch.

This commit makes it so that:

 - no condition other than ex.reason < 0 is checked in the if
   predicate

 - there's no "else" block to check whether no exception was caught

 - there's no code between the TRY_CATCH (TRY) block and the
   'if (ex.reason < 0)' block (CATCH).

 - the exception object is no longer referred to outside the if/catch
   block.  Note the local volatile exception objects that are
   currently defined inside functions that use TRY_CATCH will
   disappear.  In cases it's more convenient to still refer to the
   exception outside the catch block, a new non-volatile local is
   added and copy to that object is made within the catch block.

The following patches should make this all clearer.

gdb/ChangeLog:
2015-03-07  Pedro Alves  <palves@redhat.com>

	* amd64-tdep.c (amd64_frame_cache, amd64_sigtramp_frame_cache)
	(amd64_epilogue_frame_cache): Normal exception handling code.
	* break-catch-throw.c (check_status_exception_catchpoint)
	(re_set_exception_catchpoint): Ditto.
	* cli/cli-interp.c (safe_execute_command):
	* cli/cli-script.c (script_from_file): Ditto.
	* compile/compile-c-symbols.c (generate_c_for_for_one_variable):
	Ditto.
	* compile/compile-object-run.c (compile_object_run): Ditto.
	* cp-abi.c (baseclass_offset): Ditto.
	* cp-valprint.c (cp_print_value): Ditto.
	* exceptions.c (catch_exceptions_with_msg):
	* frame-unwind.c (frame_unwind_try_unwinder): Ditto.
	* frame.c (get_frame_address_in_block_if_available): Ditto.
	* i386-tdep.c (i386_frame_cache, i386_epilogue_frame_cache)
	(i386_sigtramp_frame_cache): Ditto.
	* infcmd.c (post_create_inferior): Ditto.
	* linespec.c (parse_linespec, find_linespec_symbols):
	* p-valprint.c (pascal_object_print_value): Ditto.
	* parse.c (parse_expression_for_completion): Ditto.
	* python/py-finishbreakpoint.c (bpfinishpy_init): Ditto.
	* remote.c (remote_get_noisy_reply): Ditto.
	* s390-linux-tdep.c (s390_frame_unwind_cache): Ditto.
	* solib-svr4.c (solib_svr4_r_map): Ditto.
2015-03-07 14:56:43 +00:00

140 lines
4.0 KiB
C

/* Call module for 'compile' command.
Copyright (C) 2014-2015 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 3 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, see <http://www.gnu.org/licenses/>. */
#include "defs.h"
#include "compile-object-run.h"
#include "value.h"
#include "infcall.h"
#include "objfiles.h"
#include "compile-internal.h"
#include "dummy-frame.h"
/* Helper for do_module_cleanup. */
struct do_module_cleanup
{
/* Boolean to set true upon a call of do_module_cleanup.
The pointer may be NULL. */
int *executedp;
/* .c file OBJFILE was built from. It needs to be xfree-d. */
char *source_file;
/* objfile_name of our objfile. */
char objfile_name_string[1];
};
/* Cleanup everything after the inferior function dummy frame gets
discarded. */
static dummy_frame_dtor_ftype do_module_cleanup;
static void
do_module_cleanup (void *arg)
{
struct do_module_cleanup *data = arg;
struct objfile *objfile;
if (data->executedp != NULL)
*data->executedp = 1;
ALL_OBJFILES (objfile)
if ((objfile->flags & OBJF_USERLOADED) == 0
&& (strcmp (objfile_name (objfile), data->objfile_name_string) == 0))
{
free_objfile (objfile);
/* It may be a bit too pervasive in this dummy_frame dtor callback. */
clear_symtab_users (0);
break;
}
/* Delete the .c file. */
unlink (data->source_file);
xfree (data->source_file);
/* Delete the .o file. */
unlink (data->objfile_name_string);
xfree (data);
}
/* Perform inferior call of MODULE. This function may throw an error.
This function may leave files referenced by MODULE on disk until
the inferior call dummy frame is discarded. This function may throw errors.
Thrown errors and left MODULE files are unrelated events. Caller must no
longer touch MODULE's memory after this function has been called. */
void
compile_object_run (struct compile_module *module)
{
struct value *func_val;
struct frame_id dummy_id;
struct cleanup *cleanups;
struct do_module_cleanup *data;
volatile struct gdb_exception ex;
const char *objfile_name_s = objfile_name (module->objfile);
int dtor_found, executed = 0;
CORE_ADDR func_addr = module->func_addr;
CORE_ADDR regs_addr = module->regs_addr;
data = xmalloc (sizeof (*data) + strlen (objfile_name_s));
data->executedp = &executed;
data->source_file = xstrdup (module->source_file);
strcpy (data->objfile_name_string, objfile_name_s);
xfree (module->source_file);
xfree (module);
TRY_CATCH (ex, RETURN_MASK_ERROR)
{
func_val = value_from_pointer
(builtin_type (target_gdbarch ())->builtin_func_ptr,
func_addr);
if (regs_addr == 0)
call_function_by_hand_dummy (func_val, 0, NULL,
do_module_cleanup, data);
else
{
struct value *arg_val;
arg_val = value_from_pointer
(builtin_type (target_gdbarch ())->builtin_func_ptr,
regs_addr);
call_function_by_hand_dummy (func_val, 1, &arg_val,
do_module_cleanup, data);
}
}
if (ex.reason < 0)
{
/* In the case of DTOR_FOUND or in the case of EXECUTED nothing
needs to be done. */
dtor_found = find_dummy_frame_dtor (do_module_cleanup, data);
if (!executed)
data->executedp = NULL;
gdb_assert (!(dtor_found && executed));
if (!dtor_found && !executed)
do_module_cleanup (data);
throw_exception (ex);
}
dtor_found = find_dummy_frame_dtor (do_module_cleanup, data);
gdb_assert (!dtor_found && executed);
}