Re: RFA: patch to display ia64 function pointers

Re: RFA: patch to display ia64 function pointers

[Michael Elizabeth Chastain]

jj> I am also about to submit a change to prologue examination
jj> to handle glibc's sleep() function.

Hoo hah, that sounds familiar.

Also check select() while you are at it.  On my i686-pc-linux-gnu
most of the test suite problems showed up with sleep(), but real code
is more likely to be in select().

And check out testsuite/gdb.arch/i386-prologue.exp i386-prologue.c.

This has to be done for a lot of targets.  :(  Daniel J suggested
using the s390-tdep.c 'abstract execution' engine on every target
and I think that's a good idea.

Michael C

RFA: patch to display ia64 function pointers

[J. Johnston]

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The following patch fixes the problem when displaying structs or function
pointers that actually point to a function descriptor per the ia64 ABI.
Currently, the function descriptor pointer is erroneously interpreted as
pointing to a function and so gdb spits out some meaningless information.

With the patch, you get to see the actual function that the pointer
is referencing via the function descriptor.

Ok to commit?

2003-07-31  Jeff Johnston  <jjohnstn@redhat.com>

	* ia64-tdep.c (ia64_convert_from_func_addr): New function.
	(ia64_gdbarch_init): Call set_gdbarch_convert_from_func_addr().

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Index: ia64-tdep.c
===================================================================
RCS file: /cvs/src/src/gdb/ia64-tdep.c,v
retrieving revision 1.92
diff -u -p -r1.92 ia64-tdep.c
--- ia64-tdep.c	23 Jul 2003 18:32:19 -0000	1.92
+++ ia64-tdep.c	31 Jul 2003 21:55:46 -0000
@@ -1852,6 +1852,23 @@ find_func_descr (CORE_ADDR faddr, CORE_A
   return fdesc; 
 }
 
+/* Use the following routine when printing out function pointers
+   so the user can see the function address rather than just the
+   function descriptor.  */
+static CORE_ADDR
+ia64_convert_from_func_ptr_addr (CORE_ADDR addr)
+{
+  struct obj_section *s;
+
+  s = find_pc_section (addr);
+
+  /* check if ADDR points to a function descriptor.  */
+  if (s && strcmp (s->the_bfd_section->name, ".opd") == 0)
+    return read_memory_unsigned_integer (addr, 8);
+
+  return addr;
+}
+
 static CORE_ADDR
 ia64_push_dummy_call (struct gdbarch *gdbarch, CORE_ADDR func_addr,
 		      struct regcache *regcache, CORE_ADDR bp_addr,
@@ -2277,6 +2294,7 @@ ia64_gdbarch_init (struct gdbarch_info i
   set_gdbarch_deprecated_register_convertible (gdbarch, ia64_register_convertible);
   set_gdbarch_deprecated_register_convert_to_virtual (gdbarch, ia64_register_convert_to_virtual);
   set_gdbarch_deprecated_register_convert_to_raw (gdbarch, ia64_register_convert_to_raw);
+  set_gdbarch_convert_from_func_ptr_addr (gdbarch, ia64_convert_from_func_ptr_addr);
 
   set_gdbarch_use_struct_convention (gdbarch, ia64_use_struct_convention);
   set_gdbarch_deprecated_extract_return_value (gdbarch, ia64_extract_return_value);

Re: RFA: patch to display ia64 function pointers

[Kevin Buettner]

On Jul 31,  6:01pm, J. Johnston wrote:

> The following patch fixes the problem when displaying structs or function
> pointers that actually point to a function descriptor per the ia64 ABI.
> Currently, the function descriptor pointer is erroneously interpreted as
> pointing to a function and so gdb spits out some meaningless information.
> 
> With the patch, you get to see the actual function that the pointer
> is referencing via the function descriptor.
> 
> Ok to commit?
> 
> 2003-07-31  Jeff Johnston  <jjohnstn@redhat.com>
> 
> 	* ia64-tdep.c (ia64_convert_from_func_addr): New function.
> 	(ia64_gdbarch_init): Call set_gdbarch_convert_from_func_addr().

Okay.

Thanks,

Kevin

P.S. Please let me know if you're waiting on me to review any more of
your patches.

Re: RFA: patch to display ia64 function pointers

[J. Johnston]

Kevin Buettner wrote:
> On Jul 31,  6:01pm, J. Johnston wrote:
> 
> 
>>The following patch fixes the problem when displaying structs or function
>>pointers that actually point to a function descriptor per the ia64 ABI.
>>Currently, the function descriptor pointer is erroneously interpreted as
>>pointing to a function and so gdb spits out some meaningless information.
>>
>>With the patch, you get to see the actual function that the pointer
>>is referencing via the function descriptor.
>>
>>Ok to commit?
>>
>>2003-07-31  Jeff Johnston  <jjohnstn@redhat.com>
>>
>>	* ia64-tdep.c (ia64_convert_from_func_addr): New function.
>>	(ia64_gdbarch_init): Call set_gdbarch_convert_from_func_addr().
> 
> 
> Okay.
> 
> Thanks,
> 
> Kevin
> 
> P.S. Please let me know if you're waiting on me to review any more of
> your patches.
> 

Patch checked in, thanks.  No outstanding ia64 patches at the moment.
There is a testsuite change to dump.exp to accomodate ia64 which I
have submitted.  I am also about to submit a change to prologue examination
to handle glibc's sleep() function.

-- Jeff J.