[ppc64-linux] gdbarch hook to find true execution entry point

[Jim Blandy <jimb@redhat.com>]

2003-06-11  Jim Blandy  <jimb@redhat.com>

	* gdbarch.sh (gdbarch_bfd_entry_point): New gdbarch method.
	* arch-utils.c (generic_bfd_entry_point): New function.
	* arch-utils.h (generic_bfd_entry_point): New declaration.
	* gdbarch.c, gdbarch.h: Regenerated.
	* solib-svr4.c (enable_break): Call it, instead of accessing
	tmp_bfd->start_address directly.
  
Index: gdb/gdbarch.sh
===================================================================
RCS file: /cvs/src/src/gdb/gdbarch.sh,v
retrieving revision 1.237
diff -c -r1.237 gdbarch.sh
*** gdb/gdbarch.sh	17 May 2003 05:59:58 -0000	1.237
--- gdb/gdbarch.sh	11 Jun 2003 13:16:31 -0000
***************
*** 654,659 ****
--- 654,664 ----
  f:2:TARGET_PRINT_INSN:int:print_insn:bfd_vma vma, disassemble_info *info:vma, info:::legacy_print_insn::0
  f:2:SKIP_TRAMPOLINE_CODE:CORE_ADDR:skip_trampoline_code:CORE_ADDR pc:pc:::generic_skip_trampoline_code::0
  
+ # The actual code address at which ABFD would begin execution.  Note
+ # that on some architectures (like 64-bit PowerPC Linux),
+ # bfd_get_start_address actually points to a function descriptor, not
+ # the start function's entry point itself.
+ m:1::CORE_ADDR:bfd_entry_point:bfd *abfd:abfd:::generic_bfd_entry_point::0
  
  # For SVR4 shared libraries, each call goes through a small piece of
  # trampoline code in the ".plt" section.  IN_SOLIB_CALL_TRAMPOLINE evaluates
Index: gdb/arch-utils.c
===================================================================
RCS file: /cvs/src/src/gdb/arch-utils.c,v
retrieving revision 1.83.4.1
diff -c -r1.83.4.1 arch-utils.c
*** gdb/arch-utils.c	11 Jun 2003 06:40:14 -0000	1.83.4.1
--- gdb/arch-utils.c	11 Jun 2003 13:16:26 -0000
***************
*** 375,380 ****
--- 375,386 ----
    return 0;
  }
  
+ CORE_ADDR
+ generic_bfd_entry_point (struct gdbarch *gdbarch, bfd *abfd)
+ {
+   return bfd_get_start_address (abfd);
+ }
+ 
  /* Legacy version of target_virtual_frame_pointer().  Assumes that
     there is an DEPRECATED_FP_REGNUM and that it is the same, cooked or
     raw.  */
Index: gdb/arch-utils.h
===================================================================
RCS file: /cvs/src/src/gdb/arch-utils.h,v
retrieving revision 1.46.4.1
diff -c -r1.46.4.1 arch-utils.h
*** gdb/arch-utils.h	11 Jun 2003 06:40:14 -0000	1.46.4.1
--- gdb/arch-utils.h	11 Jun 2003 13:16:26 -0000
***************
*** 89,94 ****
--- 89,98 ----
     being passed */
  extern int frame_num_args_unknown (struct frame_info *fi);
  
+ /* Return the start address of ABFD.  This is exactly like
+    bfd_get_start_address, except that it's a gdbarch function.  */
+ extern CORE_ADDR generic_bfd_entry_point (struct gdbarch *gdbarch, bfd *abfd);
+ 
  
  /* The following DEPRECATED interfaces are for pre- multi-arch legacy
     targets. */
Index: gdb/gdbarch.c
===================================================================
RCS file: /cvs/src/src/gdb/gdbarch.c,v
retrieving revision 1.216
diff -c -r1.216 gdbarch.c
*** gdb/gdbarch.c	17 May 2003 05:59:58 -0000	1.216
--- gdb/gdbarch.c	11 Jun 2003 13:16:28 -0000
***************
*** 263,268 ****
--- 263,269 ----
    gdbarch_software_single_step_ftype *software_single_step;
    gdbarch_print_insn_ftype *print_insn;
    gdbarch_skip_trampoline_code_ftype *skip_trampoline_code;
+   gdbarch_bfd_entry_point_ftype *bfd_entry_point;
    gdbarch_in_solib_call_trampoline_ftype *in_solib_call_trampoline;
    gdbarch_in_solib_return_trampoline_ftype *in_solib_return_trampoline;
    gdbarch_pc_in_sigtramp_ftype *pc_in_sigtramp;
***************
*** 429,434 ****
--- 430,436 ----
    0,
    0,
    0,
+   generic_bfd_entry_point,
    0,
    0,
    0,
***************
*** 555,560 ****
--- 557,563 ----
    current_gdbarch->smash_text_address = core_addr_identity;
    current_gdbarch->print_insn = legacy_print_insn;
    current_gdbarch->skip_trampoline_code = generic_skip_trampoline_code;
+   current_gdbarch->bfd_entry_point = generic_bfd_entry_point;
    current_gdbarch->in_solib_call_trampoline = generic_in_solib_call_trampoline;
    current_gdbarch->in_solib_return_trampoline = generic_in_solib_return_trampoline;
    current_gdbarch->pc_in_sigtramp = legacy_pc_in_sigtramp;
***************
*** 745,750 ****
--- 748,754 ----
    /* Skip verify of software_single_step, has predicate */
    /* Skip verify of print_insn, invalid_p == 0 */
    /* Skip verify of skip_trampoline_code, invalid_p == 0 */
+   /* Skip verify of bfd_entry_point, invalid_p == 0 */
    /* Skip verify of in_solib_call_trampoline, invalid_p == 0 */
    /* Skip verify of in_solib_return_trampoline, invalid_p == 0 */
    /* Skip verify of pc_in_sigtramp, invalid_p == 0 */
***************
*** 788,793 ****
--- 792,801 ----
                        GDB_MULTI_ARCH);
    if (GDB_MULTI_ARCH)
      fprintf_unfiltered (file,
+                         "gdbarch_dump: bfd_entry_point = 0x%08lx\n",
+                         (long) current_gdbarch->bfd_entry_point);
+   if (GDB_MULTI_ARCH)
+     fprintf_unfiltered (file,
                          "gdbarch_dump: gdbarch_frame_align_p() = %d\n",
                          gdbarch_frame_align_p (current_gdbarch));
    if (GDB_MULTI_ARCH)
***************
*** 5330,5335 ****
--- 5338,5362 ----
                                    gdbarch_skip_trampoline_code_ftype skip_trampoline_code)
  {
    gdbarch->skip_trampoline_code = skip_trampoline_code;
+ }
+ 
+ CORE_ADDR
+ gdbarch_bfd_entry_point (struct gdbarch *gdbarch, bfd *abfd)
+ {
+   gdb_assert (gdbarch != NULL);
+   if (gdbarch->bfd_entry_point == 0)
+     internal_error (__FILE__, __LINE__,
+                     "gdbarch: gdbarch_bfd_entry_point invalid");
+   if (gdbarch_debug >= 2)
+     fprintf_unfiltered (gdb_stdlog, "gdbarch_bfd_entry_point called\n");
+   return gdbarch->bfd_entry_point (gdbarch, abfd);
+ }
+ 
+ void
+ set_gdbarch_bfd_entry_point (struct gdbarch *gdbarch,
+                              gdbarch_bfd_entry_point_ftype bfd_entry_point)
+ {
+   gdbarch->bfd_entry_point = bfd_entry_point;
  }
  
  int
Index: gdb/gdbarch.h
===================================================================
RCS file: /cvs/src/src/gdb/gdbarch.h,v
retrieving revision 1.185
diff -c -r1.185 gdbarch.h
*** gdb/gdbarch.h	17 May 2003 05:59:58 -0000	1.185
--- gdb/gdbarch.h	11 Jun 2003 13:16:29 -0000
***************
*** 2831,2836 ****
--- 2831,2845 ----
  #endif
  #endif
  
+ /* The actual code address at which ABFD would begin execution.  Note
+    that on some architectures (like 64-bit PowerPC Linux),
+    bfd_get_start_address actually points to a function descriptor, not
+    the start function's entry point itself. */
+ 
+ typedef CORE_ADDR (gdbarch_bfd_entry_point_ftype) (struct gdbarch *gdbarch, bfd *abfd);
+ extern CORE_ADDR gdbarch_bfd_entry_point (struct gdbarch *gdbarch, bfd *abfd);
+ extern void set_gdbarch_bfd_entry_point (struct gdbarch *gdbarch, gdbarch_bfd_entry_point_ftype *bfd_entry_point);
+ 
  /* For SVR4 shared libraries, each call goes through a small piece of
     trampoline code in the ".plt" section.  IN_SOLIB_CALL_TRAMPOLINE evaluates
     to nonzero if we are currently stopped in one of these. */
Index: gdb/solib-svr4.c
===================================================================
RCS file: /cvs/src/src/gdb/solib-svr4.c,v
retrieving revision 1.32.8.2
diff -c -r1.32.8.2 solib-svr4.c
*** gdb/solib-svr4.c	11 Jun 2003 13:00:34 -0000	1.32.8.2
--- gdb/solib-svr4.c	11 Jun 2003 13:16:32 -0000
***************
*** 1022,1028 ****
  	 the current pc (which should point at the entry point for the
  	 dynamic linker) and subtracting the offset of the entry point.  */
        if (!load_addr_found)
! 	load_addr = read_pc () - tmp_bfd->start_address;
  
        /* Record the relocated start and end address of the dynamic linker
           text and plt section for svr4_in_dynsym_resolve_code.  */
--- 1022,1029 ----
  	 the current pc (which should point at the entry point for the
  	 dynamic linker) and subtracting the offset of the entry point.  */
        if (!load_addr_found)
! 	load_addr = (read_pc ()
!                      - generic_bfd_entry_point (current_gdbarch, tmp_bfd));
  
        /* Record the relocated start and end address of the dynamic linker
           text and plt section for svr4_in_dynsym_resolve_code.  */