* arch-utils.c, arch-utils.h (default_convert_from_func_ptr_addr):

	New function.
	* gdbarch.sh (CONVERT_FROM_FUNC_PTR_ADDR):  Add.
	* gdbarch.c, gdbarch.h:  Regenerate.
	* valops.c (find_function_addr):  Use CONVERT_FROM_FUNC_PTR_ADDR
	unconditionally.

	* config/rs6000/tm-rs6000.h (CONVERT_FROM_FUNC_PTR_ADDR):  Delete
	definition.
	* config/powerpc/tm-linux.h (CONVERT_FROM_FUNC_PTR_ADDR):  Remove
	undef.
	* rs6000-tdep.c (rs6000_convert_from_func_ptr_addr):  Fix comment.
	(rs6000_gdbarch_init):  Register rs6000_convert_from_func_ptr_addr
	if not ELFOSABI_LINUX.

10 files changed, 84 insertions, 28 deletions

diff --git a/gdb/ChangeLog b/gdb/ChangeLog
index a615486..959e04a 100644
--- a/gdb/ChangeLog
+++ b/gdb/ChangeLog
@@ -1,3 +1,20 @@
+2000-10-26  Peter Schauer  <pes@regent.e-technik.tu-muenchen.de>
+
+	* arch-utils.c, arch-utils.h (default_convert_from_func_ptr_addr):
+	New function.
+	* gdbarch.sh (CONVERT_FROM_FUNC_PTR_ADDR):  Add.
+	* gdbarch.c, gdbarch.h:  Regenerate.
+	* valops.c (find_function_addr):  Use CONVERT_FROM_FUNC_PTR_ADDR
+	unconditionally.
+
+	* config/rs6000/tm-rs6000.h (CONVERT_FROM_FUNC_PTR_ADDR):  Delete
+	definition.
+	* config/powerpc/tm-linux.h (CONVERT_FROM_FUNC_PTR_ADDR):  Remove
+	undef.
+	* rs6000-tdep.c (rs6000_convert_from_func_ptr_addr):  Fix comment.
+	(rs6000_gdbarch_init):  Register rs6000_convert_from_func_ptr_addr
+	if not ELFOSABI_LINUX.
+
 2000-10-25  Kevin Buettner  <kevinb@redhat.com>
 
 	* config/rs6000/rs6000lynx.mt (TDEPFILES): Revert 2000-10-24
diff --git a/gdb/arch-utils.c b/gdb/arch-utils.c
index 02eeaea..d58eb45 100644
--- a/gdb/arch-utils.c
+++ b/gdb/arch-utils.c
@@ -226,6 +226,13 @@ default_register_sim_regno (int num)
   return num;
 }
 
+
+CORE_ADDR
+default_convert_from_func_ptr_addr (CORE_ADDR addr)
+{
+  return addr;
+}
+
 /* Functions to manipulate the endianness of the target.  */
 
 #ifdef TARGET_BYTE_ORDER_SELECTABLE
diff --git a/gdb/arch-utils.h b/gdb/arch-utils.h
index 579953f..2645a95 100644
--- a/gdb/arch-utils.h
+++ b/gdb/arch-utils.h
@@ -93,4 +93,8 @@ extern int (*target_architecture_hook) (const struct bfd_arch_info *);
 
 extern int default_register_sim_regno (int reg_nr);
 
+/* Default conversion of function pointer address - returns address.  */
+
+extern CORE_ADDR default_convert_from_func_ptr_addr (CORE_ADDR addr);
+
 #endif
diff --git a/gdb/config/powerpc/tm-linux.h b/gdb/config/powerpc/tm-linux.h
index 99d4c96..cf3275e 100644
--- a/gdb/config/powerpc/tm-linux.h
+++ b/gdb/config/powerpc/tm-linux.h
@@ -55,9 +55,6 @@ extern int ppc_linux_in_sigtramp (CORE_ADDR pc, char *func_name);
 #define CANNOT_STORE_REGISTER(regno) ((regno) >= MQ_REGNUM)
 #endif
 
-/* Linux doesn't use the PowerOpen ABI for function pointer representation */
-#undef CONVERT_FROM_FUNC_PTR_ADDR
-
 #if 0 /* If skip_prologue() isn't too greedy, we don't need this */
 /* There is some problem with the debugging symbols generated by the
    compiler such that the debugging symbol for the first line of a
diff --git a/gdb/config/rs6000/tm-rs6000.h b/gdb/config/rs6000/tm-rs6000.h
index 9bf8381..beb445d 100644
--- a/gdb/config/rs6000/tm-rs6000.h
+++ b/gdb/config/rs6000/tm-rs6000.h
@@ -97,23 +97,6 @@ extern void aix_process_linenos (void);
 /* Default offset from SP where the LR is stored */
 #define	DEFAULT_LR_SAVE 8
 
-/* Usually a function pointer's representation is simply the address
-   of the function. On the RS/6000 however, a function pointer is
-   represented by a pointer to a TOC entry. This TOC entry contains
-   three words, the first word is the address of the function, the
-   second word is the TOC pointer (r2), and the third word is the
-   static chain value.  Throughout GDB it is currently assumed that a
-   function pointer contains the address of the function, which is not
-   easy to fix.  In addition, the conversion of a function address to
-   a function pointer would require allocation of a TOC entry in the
-   inferior's memory space, with all its drawbacks.  To be able to
-   call C++ virtual methods in the inferior (which are called via
-   function pointers), find_function_addr uses this macro to get the
-   function address from a function pointer.  */
-
-#define CONVERT_FROM_FUNC_PTR_ADDR rs6000_convert_from_func_ptr_addr
-extern CORE_ADDR rs6000_convert_from_func_ptr_addr (CORE_ADDR);
-
 /* Flag for machine-specific stuff in shared files.  FIXME */
 #define IBM6000_TARGET
 
diff --git a/gdb/gdbarch.c b/gdb/gdbarch.c
index 1bdf278..bd705f9 100644
--- a/gdb/gdbarch.c
+++ b/gdb/gdbarch.c
@@ -232,6 +232,7 @@ struct gdbarch
   const struct floatformat * float_format;
   const struct floatformat * double_format;
   const struct floatformat * long_double_format;
+  gdbarch_convert_from_func_ptr_addr_ftype *convert_from_func_ptr_addr;
 };
 
 
@@ -354,6 +355,7 @@ struct gdbarch startup_gdbarch =
   0,
   0,
   0,
+  0,
   /* startup_gdbarch() */
 };
 
@@ -429,6 +431,7 @@ gdbarch_alloc (const struct gdbarch_info *info,
   gdbarch->frame_args_skip = -1;
   gdbarch->frameless_function_invocation = generic_frameless_function_invocation_not;
   gdbarch->extra_stack_alignment_needed = 1;
+  gdbarch->convert_from_func_ptr_addr = default_convert_from_func_ptr_addr;
   /* gdbarch_alloc() */
 
   return gdbarch;
@@ -665,6 +668,7 @@ verify_gdbarch (struct gdbarch *gdbarch)
     gdbarch->double_format = default_double_format (gdbarch);
   if (gdbarch->long_double_format == 0)
     gdbarch->long_double_format = &floatformat_unknown;
+  /* Skip verify of convert_from_func_ptr_addr, invalid_p == 0 */
 }
 
 
@@ -1293,6 +1297,12 @@ gdbarch_dump (struct gdbarch *gdbarch, struct ui_file *file)
                       "gdbarch_dump: TARGET_LONG_DOUBLE_FORMAT # %s\n",
                       XSTRING (TARGET_LONG_DOUBLE_FORMAT));
 #endif
+#ifdef CONVERT_FROM_FUNC_PTR_ADDR
+  fprintf_unfiltered (file,
+                      "gdbarch_dump: %s # %s\n",
+                      "CONVERT_FROM_FUNC_PTR_ADDR(addr)",
+                      XSTRING (CONVERT_FROM_FUNC_PTR_ADDR (addr)));
+#endif
 #ifdef TARGET_ARCHITECTURE
   if (TARGET_ARCHITECTURE != NULL)
     fprintf_unfiltered (file,
@@ -1949,6 +1959,13 @@ gdbarch_dump (struct gdbarch *gdbarch, struct ui_file *file)
                       "gdbarch_dump: TARGET_LONG_DOUBLE_FORMAT = %ld\n",
                       (long) TARGET_LONG_DOUBLE_FORMAT);
 #endif
+#ifdef CONVERT_FROM_FUNC_PTR_ADDR
+  if (GDB_MULTI_ARCH)
+    fprintf_unfiltered (file,
+                        "gdbarch_dump: CONVERT_FROM_FUNC_PTR_ADDR = 0x%08lx\n",
+                        (long) current_gdbarch->convert_from_func_ptr_addr
+                        /*CONVERT_FROM_FUNC_PTR_ADDR ()*/);
+#endif
   if (current_gdbarch->dump_tdep != NULL)
     current_gdbarch->dump_tdep (current_gdbarch, file);
 }
@@ -3737,6 +3754,23 @@ set_gdbarch_long_double_format (struct gdbarch *gdbarch,
   gdbarch->long_double_format = long_double_format;
 }
 
+CORE_ADDR
+gdbarch_convert_from_func_ptr_addr (struct gdbarch *gdbarch, CORE_ADDR addr)
+{
+  if (gdbarch->convert_from_func_ptr_addr == 0)
+    internal_error ("gdbarch: gdbarch_convert_from_func_ptr_addr invalid");
+  if (gdbarch_debug >= 2)
+    fprintf_unfiltered (gdb_stdlog, "gdbarch_convert_from_func_ptr_addr called\n");
+  return gdbarch->convert_from_func_ptr_addr (addr);
+}
+
+void
+set_gdbarch_convert_from_func_ptr_addr (struct gdbarch *gdbarch,
+                                        gdbarch_convert_from_func_ptr_addr_ftype convert_from_func_ptr_addr)
+{
+  gdbarch->convert_from_func_ptr_addr = convert_from_func_ptr_addr;
+}
+
 
 /* Keep a registrary of per-architecture data-pointers required by GDB
    modules. */
diff --git a/gdb/gdbarch.h b/gdb/gdbarch.h
index 82ffdce..87cbbd9 100644
--- a/gdb/gdbarch.h
+++ b/gdb/gdbarch.h
@@ -1338,6 +1338,20 @@ extern void set_gdbarch_long_double_format (struct gdbarch *gdbarch, const struc
 #endif
 #endif
 
+/* Default (function) for non- multi-arch platforms. */
+#if (!GDB_MULTI_ARCH) && !defined (CONVERT_FROM_FUNC_PTR_ADDR)
+#define CONVERT_FROM_FUNC_PTR_ADDR(addr) (default_convert_from_func_ptr_addr (addr))
+#endif
+
+typedef CORE_ADDR (gdbarch_convert_from_func_ptr_addr_ftype) (CORE_ADDR addr);
+extern CORE_ADDR gdbarch_convert_from_func_ptr_addr (struct gdbarch *gdbarch, CORE_ADDR addr);
+extern void set_gdbarch_convert_from_func_ptr_addr (struct gdbarch *gdbarch, gdbarch_convert_from_func_ptr_addr_ftype *convert_from_func_ptr_addr);
+#if GDB_MULTI_ARCH
+#if (GDB_MULTI_ARCH > GDB_MULTI_ARCH_PARTIAL) || !defined (CONVERT_FROM_FUNC_PTR_ADDR)
+#define CONVERT_FROM_FUNC_PTR_ADDR(addr) (gdbarch_convert_from_func_ptr_addr (current_gdbarch, addr))
+#endif
+#endif
+
 extern struct gdbarch_tdep *gdbarch_tdep (struct gdbarch *gdbarch);
 
 
diff --git a/gdb/gdbarch.sh b/gdb/gdbarch.sh
index 991ec32..11a4a77 100755
--- a/gdb/gdbarch.sh
+++ b/gdb/gdbarch.sh
@@ -472,6 +472,7 @@ F:2:SAVE_DUMMY_FRAME_TOS:void:save_dummy_frame_tos:CORE_ADDR sp:sp::0:0
 v:2:TARGET_FLOAT_FORMAT:const struct floatformat *:float_format::::::default_float_format (gdbarch)
 v:2:TARGET_DOUBLE_FORMAT:const struct floatformat *:double_format::::::default_double_format (gdbarch)
 v:2:TARGET_LONG_DOUBLE_FORMAT:const struct floatformat *:long_double_format::::::&floatformat_unknown
+f:2:CONVERT_FROM_FUNC_PTR_ADDR:CORE_ADDR:convert_from_func_ptr_addr:CORE_ADDR addr:addr:::default_convert_from_func_ptr_addr::0
 EOF
 }
 
diff --git a/gdb/rs6000-tdep.c b/gdb/rs6000-tdep.c
index fa06340..252ea77 100644
--- a/gdb/rs6000-tdep.c
+++ b/gdb/rs6000-tdep.c
@@ -1541,11 +1541,11 @@ rs6000_create_inferior (int pid)
    a function pointer would require allocation of a TOC entry in the
    inferior's memory space, with all its drawbacks.  To be able to
    call C++ virtual methods in the inferior (which are called via
-   function pointers), find_function_addr uses this macro to get the
+   function pointers), find_function_addr uses this function to get the
    function address from a function pointer.  */
 
-/* Return nonzero if ADDR (a function pointer) is in the data space and
-   is therefore a special function pointer.  */
+/* Return real function address if ADDR (a function pointer) is in the data
+   space and is therefore a special function pointer.  */
 
 CORE_ADDR
 rs6000_convert_from_func_ptr_addr (CORE_ADDR addr)
@@ -2196,6 +2196,10 @@ rs6000_gdbarch_init (struct gdbarch_info info, struct gdbarch_list *arches)
 
       set_gdbarch_frame_init_saved_regs (gdbarch, rs6000_frame_init_saved_regs);
       set_gdbarch_init_extra_frame_info (gdbarch, rs6000_init_extra_frame_info);
+
+      /* Handle RS/6000 function pointers.  */
+      set_gdbarch_convert_from_func_ptr_addr (gdbarch,
+	rs6000_convert_from_func_ptr_addr);
     }
   set_gdbarch_frame_args_address (gdbarch, rs6000_frame_args_address);
   set_gdbarch_frame_locals_address (gdbarch, rs6000_frame_args_address);
diff --git a/gdb/valops.c b/gdb/valops.c
index 8a7f036..7feec53 100644
--- a/gdb/valops.c
+++ b/gdb/valops.c
@@ -1249,12 +1249,7 @@ find_function_addr (value_ptr function, struct type **retval_type)
       if (TYPE_CODE (ftype) == TYPE_CODE_FUNC
 	  || TYPE_CODE (ftype) == TYPE_CODE_METHOD)
 	{
-#ifdef CONVERT_FROM_FUNC_PTR_ADDR
-	  /* FIXME: This is a workaround for the unusual function
-	     pointer representation on the RS/6000, see comment
-	     in config/rs6000/tm-rs6000.h  */
 	  funaddr = CONVERT_FROM_FUNC_PTR_ADDR (funaddr);
-#endif
 	  value_type = TYPE_TARGET_TYPE (ftype);
 	}
       else