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Re: [patch] cleanup: Remove INVALID_ENTRY_POINT (+FR-V modification)
Hi Pedro,
On Sat, 31 Oct 2009 16:42:13 +0100, Pedro Alves wrote:
> Previously, when we had a main symbol file, but the entry point was
> invalid
> (how common is that?),
If you load an object file but it would have to also run for the callers of
entry_point_address() so I am unable to reproduce such case.
> we'd return ~0 here, but now we'll return 0. Is there potential for
> breakage? inside_entry_func for instance could trigger false positives more
> often.
I agree there is a regression risk, fixed.
> /* If there's a valid and known entry point, fills ENTRY_P with it
> and return true; otherwise return false. */
> int entry_point_address (CORE_ADDR *entry_p);
Used this one + an error()-calling wrapper.
Regression tested on {x86_64,x86_64-m32,i686}-fedora12-linux-gnu.
Thanks,
Jan
2009-10-31 Jan Kratochvil <jan.kratochvil@redhat.com>
Remove INVALID_ENTRY_POINT.
* frame.c (inside_entry_func): New variable entry_point. Return 0 if
the entry point is not known.
* solib-irix.c (enable_break): Likewise.
* objfiles.c (init_entry_point_info): Stop using INVALID_ENTRY_POINT.
Initialize EI.ENTRY_POINT_P.
(entry_point_address): Rename to ...
(entry_point_address_query): ... a new function. Use EI.ENTRY_POINT_P.
(entry_point_address): New function.
(objfile_relocate): Use EI.ENTRY_POINT_P.
* objfiles.h (struct entry_info): Simplify entry_point comment. New
field entry_point_p.
(INVALID_ENTRY_POINT): Remove.
(entry_point_address_query): New prototype.
* solib-frv.c (enable_break): Check for NULL SYMFILE_OBJFILE and its
EI.ENTRY_POINT_P. Return 0 if ".interp" is not found.
--- a/gdb/frame.c
+++ b/gdb/frame.c
@@ -1650,7 +1650,12 @@ inside_main_func (struct frame_info *this_frame)
static int
inside_entry_func (struct frame_info *this_frame)
{
- return (get_frame_func (this_frame) == entry_point_address ());
+ CORE_ADDR entry_point;
+
+ if (!entry_point_address_query (&entry_point))
+ return 0;
+
+ return get_frame_func (this_frame) == entry_point;
}
/* Return a structure containing various interesting information about
--- a/gdb/objfiles.c
+++ b/gdb/objfiles.c
@@ -294,29 +294,34 @@ init_entry_point_info (struct objfile *objfile)
/* Executable file -- record its entry point so we'll recognize
the startup file because it contains the entry point. */
objfile->ei.entry_point = bfd_get_start_address (objfile->obfd);
+ objfile->ei.entry_point_p = 1;
}
else if (bfd_get_file_flags (objfile->obfd) & DYNAMIC
&& bfd_get_start_address (objfile->obfd) != 0)
- /* Some shared libraries may have entry points set and be
- runnable. There's no clear way to indicate this, so just check
- for values other than zero. */
- objfile->ei.entry_point = bfd_get_start_address (objfile->obfd);
+ {
+ /* Some shared libraries may have entry points set and be
+ runnable. There's no clear way to indicate this, so just check
+ for values other than zero. */
+ objfile->ei.entry_point = bfd_get_start_address (objfile->obfd);
+ objfile->ei.entry_point_p = 1;
+ }
else
{
/* Examination of non-executable.o files. Short-circuit this stuff. */
- objfile->ei.entry_point = INVALID_ENTRY_POINT;
+ objfile->ei.entry_point_p = 0;
}
}
-/* Get current entry point address. */
+/* If there is a valid and known entry point, function fills *ENTRY_P with it
+ and returns non-zero; otherwise it returns zero. */
-CORE_ADDR
-entry_point_address (void)
+int
+entry_point_address_query (CORE_ADDR *entry_p)
{
struct gdbarch *gdbarch;
CORE_ADDR entry_point;
- if (symfile_objfile == NULL)
+ if (symfile_objfile == NULL || !symfile_objfile->ei.entry_point_p)
return 0;
gdbarch = get_objfile_arch (symfile_objfile);
@@ -332,7 +337,21 @@ entry_point_address (void)
symbol table. */
entry_point = gdbarch_addr_bits_remove (gdbarch, entry_point);
- return entry_point;
+ *entry_p = entry_point;
+ return 1;
+}
+
+/* Get current entry point address. Call error if it is not known. */
+
+CORE_ADDR
+entry_point_address (void)
+{
+ CORE_ADDR retval;
+
+ if (!entry_point_address_query (&retval))
+ error (_("Entry point address is not known."));
+
+ return retval;
}
/* Create the terminating entry of OBJFILE's minimal symbol table.
@@ -702,7 +721,7 @@ objfile_relocate (struct objfile *objfile, struct section_offsets *new_offsets)
to be out of order. */
msymbols_sort (objfile);
- if (objfile->ei.entry_point != ~(CORE_ADDR) 0)
+ if (objfile->ei.entry_point_p)
{
/* Relocate ei.entry_point with its section offset, use SECT_OFF_TEXT
only as a fallback. */
--- a/gdb/objfiles.h
+++ b/gdb/objfiles.h
@@ -100,15 +100,11 @@ struct objfile_data;
struct entry_info
{
-
- /* The value we should use for this objects entry point.
- The illegal/unknown value needs to be something other than 0, ~0
- for instance, which is much less likely than 0. */
-
+ /* The relocated value we should use for this objfile entry point. */
CORE_ADDR entry_point;
-#define INVALID_ENTRY_POINT (~0) /* ~0 will not be in any file, we hope. */
-
+ /* Set to 1 iff ENTRY_POINT contains a valid value. */
+ unsigned entry_point_p : 1;
};
/* Sections in an objfile. The section offsets are stored in the
@@ -447,6 +443,8 @@ extern struct gdbarch *get_objfile_arch (struct objfile *);
extern void init_entry_point_info (struct objfile *);
+extern int entry_point_address_query (CORE_ADDR *entry_p);
+
extern CORE_ADDR entry_point_address (void);
extern int build_objfile_section_table (struct objfile *);
--- a/gdb/solib-frv.c
+++ b/gdb/solib-frv.c
@@ -822,30 +822,43 @@ enable_break (void)
may have changed since the last time we ran the program. */
remove_solib_event_breakpoints ();
- /* Check for the presence of a .interp section. If there is no
- such section, the executable is statically linked. */
-
- interp_sect = bfd_get_section_by_name (exec_bfd, ".interp");
-
- if (interp_sect)
+ if (symfile_objfile == NULL)
{
- enable_break1_done = 1;
- create_solib_event_breakpoint (target_gdbarch,
- symfile_objfile->ei.entry_point);
+ if (solib_frv_debug)
+ fprintf_unfiltered (gdb_stdlog,
+ "enable_break: No symbol file found.\n");
+ return 0;
+ }
+ if (!symfile_objfile->ei.entry_point_p)
+ {
if (solib_frv_debug)
fprintf_unfiltered (gdb_stdlog,
- "enable_break: solib event breakpoint placed at entry point: %s\n",
- hex_string_custom
- (symfile_objfile->ei.entry_point, 8));
+ "enable_break: Symbol file has no entry point.\n");
+ return 0;
}
- else
+
+ /* Check for the presence of a .interp section. If there is no
+ such section, the executable is statically linked. */
+
+ interp_sect = bfd_get_section_by_name (exec_bfd, ".interp");
+
+ if (interp_sect == NULL)
{
if (solib_frv_debug)
fprintf_unfiltered (gdb_stdlog,
- "enable_break: No .interp section found.\n");
+ "enable_break: No .interp section found.\n");
+ return 0;
}
+ enable_break1_done = 1;
+ create_solib_event_breakpoint (target_gdbarch,
+ symfile_objfile->ei.entry_point);
+
+ if (solib_frv_debug)
+ fprintf_unfiltered (gdb_stdlog,
+ "enable_break: solib event breakpoint placed at entry point: %s\n",
+ hex_string_custom (symfile_objfile->ei.entry_point, 8));
return 1;
}
--- a/gdb/solib-irix.c
+++ b/gdb/solib-irix.c
@@ -369,11 +369,13 @@ enable_break (void)
{
struct frame_info *frame = get_current_frame ();
struct address_space *aspace = get_frame_address_space (frame);
+ CORE_ADDR entry_point;
- base_breakpoint
- = deprecated_insert_raw_breakpoint (target_gdbarch,
- aspace,
- entry_point_address ());
+ if (!entry_point_address_query (&entry_point))
+ return 0;
+
+ base_breakpoint = deprecated_insert_raw_breakpoint (target_gdbarch,
+ aspace, entry_point);
if (base_breakpoint != NULL)
return 1;