Initial creation of sourceware repositorygdb-4_18-branchpoint

1 files changed, 845 insertions, 0 deletions

diff --git a/gdb/rs6000-nat.c b/gdb/rs6000-nat.c
new file mode 100644
index 0000000..c74a36f
--- /dev/null
+++ b/gdb/rs6000-nat.c
@@ -0,0 +1,845 @@
+/* IBM RS/6000 native-dependent code for GDB, the GNU debugger.
+   Copyright 1986, 1987, 1989, 1991, 1992, 1994, 1995, 1996, 1997, 1998
+	     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 2 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, write to the Free Software
+Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA.  */
+
+#include "defs.h"
+#include "inferior.h"
+#include "target.h"
+#include "gdbcore.h"
+#include "xcoffsolib.h"
+#include "symfile.h"
+#include "objfiles.h"
+#include "libbfd.h"  /* For bfd_cache_lookup (FIXME) */
+#include "bfd.h"
+#include "gdb-stabs.h"
+
+#include <sys/ptrace.h>
+#include <sys/reg.h>
+
+#include <sys/param.h>
+#include <sys/dir.h>
+#include <sys/user.h>
+#include <signal.h>
+#include <sys/ioctl.h>
+#include <fcntl.h>
+
+#include <a.out.h>
+#include <sys/file.h>
+#include "gdb_stat.h"
+#include <sys/core.h>
+#include <sys/ldr.h>
+
+extern int errno;
+
+extern struct vmap * map_vmap PARAMS ((bfd *bf, bfd *arch));
+
+extern struct target_ops exec_ops;
+
+static void
+vmap_exec PARAMS ((void));
+
+static void
+vmap_ldinfo PARAMS ((struct ld_info *));
+
+static struct vmap *
+add_vmap PARAMS ((struct ld_info *));
+
+static int
+objfile_symbol_add PARAMS ((char *));
+
+static void
+vmap_symtab PARAMS ((struct vmap *));
+
+static void
+fetch_core_registers PARAMS ((char *, unsigned int, int, CORE_ADDR));
+
+static void
+exec_one_dummy_insn PARAMS ((void));
+
+extern void
+fixup_breakpoints PARAMS ((CORE_ADDR low, CORE_ADDR high, CORE_ADDR delta));
+
+/* Conversion from gdb-to-system special purpose register numbers.. */
+
+static int special_regs[] = {
+  IAR,				/* PC_REGNUM	*/
+  MSR,				/* PS_REGNUM	*/
+  CR,				/* CR_REGNUM	*/
+  LR,				/* LR_REGNUM	*/
+  CTR,				/* CTR_REGNUM	*/
+  XER,				/* XER_REGNUM   */
+  MQ				/* MQ_REGNUM	*/
+};
+
+void
+fetch_inferior_registers (regno)
+  int regno;
+{
+  int ii;
+  extern char registers[];
+
+  if (regno < 0) {			/* for all registers */
+
+    /* read 32 general purpose registers. */
+
+    for (ii=0; ii < 32; ++ii)
+      *(int*)&registers[REGISTER_BYTE (ii)] = 
+	ptrace (PT_READ_GPR, inferior_pid, (PTRACE_ARG3_TYPE) ii, 0, 0);
+
+    /* read general purpose floating point registers. */
+
+    for (ii=0; ii < 32; ++ii)
+      ptrace (PT_READ_FPR, inferior_pid, 
+	      (PTRACE_ARG3_TYPE) &registers [REGISTER_BYTE (FP0_REGNUM+ii)],
+	      FPR0+ii, 0);
+
+    /* read special registers. */
+    for (ii=0; ii <= LAST_UISA_SP_REGNUM-FIRST_UISA_SP_REGNUM; ++ii)
+      *(int*)&registers[REGISTER_BYTE (FIRST_UISA_SP_REGNUM+ii)] = 
+	ptrace (PT_READ_GPR, inferior_pid, (PTRACE_ARG3_TYPE) special_regs[ii],
+		0, 0);
+
+    registers_fetched ();
+    return;
+  }
+
+  /* else an individual register is addressed. */
+
+  else if (regno < FP0_REGNUM) {		/* a GPR */
+    *(int*)&registers[REGISTER_BYTE (regno)] =
+	ptrace (PT_READ_GPR, inferior_pid, (PTRACE_ARG3_TYPE) regno, 0, 0);
+  }
+  else if (regno <= FPLAST_REGNUM) {		/* a FPR */
+    ptrace (PT_READ_FPR, inferior_pid,
+	    (PTRACE_ARG3_TYPE) &registers [REGISTER_BYTE (regno)],
+	    (regno-FP0_REGNUM+FPR0), 0);
+  }
+  else if (regno <= LAST_UISA_SP_REGNUM) { /* a special register */
+    *(int*)&registers[REGISTER_BYTE (regno)] =
+	ptrace (PT_READ_GPR, inferior_pid,
+		(PTRACE_ARG3_TYPE) special_regs[regno-FIRST_UISA_SP_REGNUM],
+		0, 0);
+  }
+  else
+    fprintf_unfiltered (gdb_stderr, 
+			"gdb error: register no %d not implemented.\n",
+			regno);
+
+  register_valid [regno] = 1;
+}
+
+/* Store our register values back into the inferior.
+   If REGNO is -1, do this for all registers.
+   Otherwise, REGNO specifies which register (so we can save time).  */
+
+void
+store_inferior_registers (regno)
+     int regno;
+{
+  extern char registers[];
+
+  errno = 0;
+
+  if (regno == -1)
+    {			/* for all registers..	*/
+      int ii;
+
+       /* execute one dummy instruction (which is a breakpoint) in inferior
+          process. So give kernel a chance to do internal house keeping.
+	  Otherwise the following ptrace(2) calls will mess up user stack
+	  since kernel will get confused about the bottom of the stack (%sp) */
+
+       exec_one_dummy_insn ();
+
+      /* write general purpose registers first! */
+      for ( ii=GPR0; ii<=GPR31; ++ii)
+	{
+	  ptrace (PT_WRITE_GPR, inferior_pid, (PTRACE_ARG3_TYPE) ii,
+		  *(int*)&registers[REGISTER_BYTE (ii)], 0);
+	  if (errno)
+	    { 
+	      perror ("ptrace write_gpr");
+	      errno = 0;
+	    }
+	}
+
+      /* write floating point registers now. */
+      for ( ii=0; ii < 32; ++ii)
+	{
+	  ptrace (PT_WRITE_FPR, inferior_pid, 
+		  (PTRACE_ARG3_TYPE) &registers[REGISTER_BYTE (FP0_REGNUM+ii)],
+		  FPR0+ii, 0);
+	  if (errno)
+	    {
+	      perror ("ptrace write_fpr");
+	      errno = 0;
+	    }
+	}
+
+      /* write special registers. */
+      for (ii=0; ii <= LAST_UISA_SP_REGNUM-FIRST_UISA_SP_REGNUM; ++ii)
+	{
+	  ptrace (PT_WRITE_GPR, inferior_pid,
+		  (PTRACE_ARG3_TYPE) special_regs[ii],
+		  *(int*)&registers[REGISTER_BYTE (FIRST_UISA_SP_REGNUM+ii)],
+		  0);
+	  if (errno)
+	    {
+	      perror ("ptrace write_gpr");
+	      errno = 0;
+	    }
+	}
+    }
+
+  /* else, a specific register number is given... */
+
+  else if (regno < FP0_REGNUM)			/* a GPR */
+    {
+      ptrace (PT_WRITE_GPR, inferior_pid, (PTRACE_ARG3_TYPE) regno,
+	      *(int*)&registers[REGISTER_BYTE (regno)], 0);
+    }
+
+  else if (regno <= FPLAST_REGNUM)		/* a FPR */
+    {
+      ptrace (PT_WRITE_FPR, inferior_pid, 
+	      (PTRACE_ARG3_TYPE) &registers[REGISTER_BYTE (regno)],
+	      regno - FP0_REGNUM + FPR0, 0);
+    }
+
+  else if (regno <= LAST_UISA_SP_REGNUM) /* a special register */
+    {
+      ptrace (PT_WRITE_GPR, inferior_pid,
+	      (PTRACE_ARG3_TYPE) special_regs [regno-FIRST_UISA_SP_REGNUM],
+	      *(int*)&registers[REGISTER_BYTE (regno)], 0);
+    }
+
+  else
+    fprintf_unfiltered (gdb_stderr,
+			"Gdb error: register no %d not implemented.\n",
+			regno);
+
+  if (errno)
+    {
+      perror ("ptrace write");
+      errno = 0;
+    }
+}
+
+/* Execute one dummy breakpoint instruction.  This way we give the kernel
+   a chance to do some housekeeping and update inferior's internal data,
+   including u_area. */
+
+static void
+exec_one_dummy_insn ()
+{
+#define	DUMMY_INSN_ADDR	(TEXT_SEGMENT_BASE)+0x200
+
+  char shadow_contents[BREAKPOINT_MAX];	/* Stash old bkpt addr contents */
+  int status, pid;
+  CORE_ADDR prev_pc;
+
+  /* We plant one dummy breakpoint into DUMMY_INSN_ADDR address. We
+     assume that this address will never be executed again by the real
+     code. */
+
+  target_insert_breakpoint (DUMMY_INSN_ADDR, shadow_contents);
+
+  errno = 0;
+
+  /* You might think this could be done with a single ptrace call, and
+     you'd be correct for just about every platform I've ever worked
+     on.  However, rs6000-ibm-aix4.1.3 seems to have screwed this up --
+     the inferior never hits the breakpoint (it's also worth noting
+     powerpc-ibm-aix4.1.3 works correctly).  */
+  prev_pc = read_pc ();
+  write_pc (DUMMY_INSN_ADDR);
+  ptrace (PT_CONTINUE, inferior_pid, (PTRACE_ARG3_TYPE)1, 0, 0);
+
+  if (errno)
+    perror ("pt_continue");
+
+  do {
+    pid = wait (&status);
+  } while (pid != inferior_pid);
+    
+  write_pc (prev_pc);
+  target_remove_breakpoint (DUMMY_INSN_ADDR, shadow_contents);
+}
+
+static void
+fetch_core_registers (core_reg_sect, core_reg_size, which, reg_addr)
+     char *core_reg_sect;
+     unsigned core_reg_size;
+     int which;
+     CORE_ADDR reg_addr;	/* Unused in this version */
+{
+  /* fetch GPRs and special registers from the first register section
+     in core bfd. */
+  if (which == 0)
+    {
+      /* copy GPRs first. */
+      memcpy (registers, core_reg_sect, 32 * 4);
+
+      /* gdb's internal register template and bfd's register section layout
+	 should share a common include file. FIXMEmgo */
+      /* then comes special registes. They are supposed to be in the same
+	 order in gdb template and bfd `.reg' section. */
+      core_reg_sect += (32 * 4);
+      memcpy (&registers [REGISTER_BYTE (FIRST_UISA_SP_REGNUM)], 
+	      core_reg_sect, 
+	      (LAST_UISA_SP_REGNUM - FIRST_UISA_SP_REGNUM + 1) * 4);
+    }
+
+  /* fetch floating point registers from register section 2 in core bfd. */
+  else if (which == 2)
+    memcpy (&registers [REGISTER_BYTE (FP0_REGNUM)], core_reg_sect, 32 * 8);
+
+  else
+    fprintf_unfiltered 
+      (gdb_stderr, 
+       "Gdb error: unknown parameter to fetch_core_registers().\n");
+}
+
+/* handle symbol translation on vmapping */
+
+static void
+vmap_symtab (vp)
+     register struct vmap *vp;
+{
+  register struct objfile *objfile;
+  struct section_offsets *new_offsets;
+  int i;
+  
+  objfile = vp->objfile;
+  if (objfile == NULL)
+    {
+      /* OK, it's not an objfile we opened ourselves.
+	 Currently, that can only happen with the exec file, so
+	 relocate the symbols for the symfile.  */
+      if (symfile_objfile == NULL)
+	return;
+      objfile = symfile_objfile;
+    }
+
+  new_offsets = alloca
+    (sizeof (struct section_offsets)
+     + sizeof (new_offsets->offsets) * objfile->num_sections);
+
+  for (i = 0; i < objfile->num_sections; ++i)
+    ANOFFSET (new_offsets, i) = ANOFFSET (objfile->section_offsets, i);
+  
+  /* The symbols in the object file are linked to the VMA of the section,
+     relocate them VMA relative.  */
+  ANOFFSET (new_offsets, SECT_OFF_TEXT) = vp->tstart - vp->tvma;
+  ANOFFSET (new_offsets, SECT_OFF_DATA) = vp->dstart - vp->dvma;
+  ANOFFSET (new_offsets, SECT_OFF_BSS) = vp->dstart - vp->dvma;
+
+  objfile_relocate (objfile, new_offsets);
+}
+
+/* Add symbols for an objfile.  */
+
+static int
+objfile_symbol_add (arg)
+     char *arg;
+{
+  struct objfile *obj = (struct objfile *) arg;
+
+  syms_from_objfile (obj, 0, 0, 0);
+  new_symfile_objfile (obj, 0, 0);
+  return 1;
+}
+
+/* Add a new vmap entry based on ldinfo() information.
+
+   If ldi->ldinfo_fd is not valid (e.g. this struct ld_info is from a
+   core file), the caller should set it to -1, and we will open the file.
+
+   Return the vmap new entry.  */
+
+static struct vmap *
+add_vmap (ldi)
+     register struct ld_info *ldi; 
+{
+  bfd *abfd, *last;
+  register char *mem, *objname;
+  struct objfile *obj;
+  struct vmap *vp;
+
+  /* This ldi structure was allocated using alloca() in 
+     xcoff_relocate_symtab(). Now we need to have persistent object 
+     and member names, so we should save them. */
+
+  mem = ldi->ldinfo_filename + strlen (ldi->ldinfo_filename) + 1;
+  mem = savestring (mem, strlen (mem));
+  objname = savestring (ldi->ldinfo_filename, strlen (ldi->ldinfo_filename));
+
+  if (ldi->ldinfo_fd < 0)
+    /* Note that this opens it once for every member; a possible
+       enhancement would be to only open it once for every object.  */
+    abfd = bfd_openr (objname, gnutarget);
+  else
+    abfd = bfd_fdopenr (objname, gnutarget, ldi->ldinfo_fd);
+  if (!abfd)
+    error ("Could not open `%s' as an executable file: %s",
+	   objname, bfd_errmsg (bfd_get_error ()));
+
+  /* make sure we have an object file */
+
+  if (bfd_check_format (abfd, bfd_object))
+    vp = map_vmap (abfd, 0);
+
+  else if (bfd_check_format (abfd, bfd_archive))
+    {
+      last = 0;
+      /* FIXME??? am I tossing BFDs?  bfd? */
+      while ((last = bfd_openr_next_archived_file (abfd, last)))
+	if (STREQ (mem, last->filename))
+	  break;
+
+      if (!last)
+	{
+	  bfd_close (abfd);
+	  /* FIXME -- should be error */
+	  warning ("\"%s\": member \"%s\" missing.", abfd->filename, mem);
+	  return 0;
+	}
+
+      if (!bfd_check_format(last, bfd_object))
+	{
+	  bfd_close (last);	/* XXX???	*/
+	  goto obj_err;
+	}
+
+      vp = map_vmap (last, abfd);
+    }
+  else
+    {
+    obj_err:
+      bfd_close (abfd);
+      error ("\"%s\": not in executable format: %s.",
+	     objname, bfd_errmsg (bfd_get_error ()));
+      /*NOTREACHED*/
+    }
+  obj = allocate_objfile (vp->bfd, 0, 0, 0);
+  vp->objfile = obj;
+
+#ifndef SOLIB_SYMBOLS_MANUAL
+  if (catch_errors (objfile_symbol_add, (char *)obj,
+		    "Error while reading shared library symbols:\n",
+		    RETURN_MASK_ALL))
+    {
+      /* Note this is only done if symbol reading was successful.  */
+      vmap_symtab (vp);
+      vp->loaded = 1;
+    }
+#endif
+  return vp;
+}
+
+/* update VMAP info with ldinfo() information
+   Input is ptr to ldinfo() results.  */
+
+static void
+vmap_ldinfo (ldi)
+     register struct ld_info *ldi;
+{
+  struct stat ii, vi;
+  register struct vmap *vp;
+  int got_one, retried;
+  int got_exec_file = 0;
+
+  /* For each *ldi, see if we have a corresponding *vp.
+     If so, update the mapping, and symbol table.
+     If not, add an entry and symbol table.  */
+
+  do {
+    char *name = ldi->ldinfo_filename;
+    char *memb = name + strlen(name) + 1;
+
+    retried = 0;
+
+    if (fstat (ldi->ldinfo_fd, &ii) < 0)
+      {
+	/* The kernel sets ld_info to -1, if the process is still using the
+	   object, and the object is removed. Keep the symbol info for the
+	   removed object and issue a warning.  */
+	warning ("%s (fd=%d) has disappeared, keeping its symbols",
+		 name, ldi->ldinfo_fd);
+        continue;
+      }
+  retry:
+    for (got_one = 0, vp = vmap; vp; vp = vp->nxt)
+      {
+	struct objfile *objfile;
+
+	/* First try to find a `vp', which is the same as in ldinfo.
+	   If not the same, just continue and grep the next `vp'. If same,
+	   relocate its tstart, tend, dstart, dend values. If no such `vp'
+	   found, get out of this for loop, add this ldi entry as a new vmap
+	   (add_vmap) and come back, find its `vp' and so on... */
+
+	/* The filenames are not always sufficient to match on. */
+
+	if ((name[0] == '/' && !STREQ(name, vp->name))
+	    || (memb[0] && !STREQ(memb, vp->member)))
+	  continue;
+
+	/* See if we are referring to the same file.
+	   We have to check objfile->obfd, symfile.c:reread_symbols might
+	   have updated the obfd after a change.  */
+	objfile = vp->objfile == NULL ? symfile_objfile : vp->objfile;
+	if (objfile == NULL
+	    || objfile->obfd == NULL
+	    || bfd_stat (objfile->obfd, &vi) < 0)
+	  {
+	    warning ("Unable to stat %s, keeping its symbols", name);
+	    continue;
+	  }
+
+	if (ii.st_dev != vi.st_dev || ii.st_ino != vi.st_ino)
+	  continue;
+
+	if (!retried)
+	  close (ldi->ldinfo_fd);
+
+	++got_one;
+
+	/* Found a corresponding VMAP.  Remap!  */
+
+	/* We can assume pointer == CORE_ADDR, this code is native only.  */
+	vp->tstart = (CORE_ADDR) ldi->ldinfo_textorg;
+	vp->tend   = vp->tstart + ldi->ldinfo_textsize;
+	vp->dstart = (CORE_ADDR) ldi->ldinfo_dataorg;
+	vp->dend   = vp->dstart + ldi->ldinfo_datasize;
+
+	/* The run time loader maps the file header in addition to the text
+	   section and returns a pointer to the header in ldinfo_textorg.
+	   Adjust the text start address to point to the real start address
+	   of the text section.  */
+	vp->tstart += vp->toffs;
+
+	/* The objfile is only NULL for the exec file.  */
+	if (vp->objfile == NULL)
+	  got_exec_file = 1;
+
+	/* relocate symbol table(s). */
+	vmap_symtab (vp);
+
+	/* There may be more, so we don't break out of the loop.  */
+      }
+
+    /* if there was no matching *vp, we must perforce create the sucker(s) */
+    if (!got_one && !retried)
+      {
+	add_vmap (ldi);
+	++retried;
+	goto retry;
+      }
+  } while (ldi->ldinfo_next
+	   && (ldi = (void *) (ldi->ldinfo_next + (char *) ldi)));
+
+  /* If we don't find the symfile_objfile anywhere in the ldinfo, it
+     is unlikely that the symbol file is relocated to the proper
+     address.  And we might have attached to a process which is
+     running a different copy of the same executable.  */
+  if (symfile_objfile != NULL && !got_exec_file)
+    {
+      warning_begin ();
+      fputs_unfiltered ("Symbol file ", gdb_stderr);
+      fputs_unfiltered (symfile_objfile->name, gdb_stderr);
+      fputs_unfiltered ("\nis not mapped; discarding it.\n\
+If in fact that file has symbols which the mapped files listed by\n\
+\"info files\" lack, you can load symbols with the \"symbol-file\" or\n\
+\"add-symbol-file\" commands (note that you must take care of relocating\n\
+symbols to the proper address).\n", gdb_stderr);
+      free_objfile (symfile_objfile);
+      symfile_objfile = NULL;
+    }
+  breakpoint_re_set ();
+}
+
+/* As well as symbol tables, exec_sections need relocation. After
+   the inferior process' termination, there will be a relocated symbol
+   table exist with no corresponding inferior process. At that time, we
+   need to use `exec' bfd, rather than the inferior process's memory space
+   to look up symbols.
+
+   `exec_sections' need to be relocated only once, as long as the exec
+   file remains unchanged.
+*/
+
+static void
+vmap_exec ()
+{
+  static bfd *execbfd;
+  int i;
+
+  if (execbfd == exec_bfd)
+    return;
+
+  execbfd = exec_bfd;
+
+  if (!vmap || !exec_ops.to_sections)
+    error ("vmap_exec: vmap or exec_ops.to_sections == 0\n");
+
+  for (i=0; &exec_ops.to_sections[i] < exec_ops.to_sections_end; i++)
+    {
+      if (STREQ(".text", exec_ops.to_sections[i].the_bfd_section->name))
+	{
+	  exec_ops.to_sections[i].addr += vmap->tstart - vmap->tvma;
+	  exec_ops.to_sections[i].endaddr += vmap->tstart - vmap->tvma;
+	}
+      else if (STREQ(".data", exec_ops.to_sections[i].the_bfd_section->name))
+	{
+	  exec_ops.to_sections[i].addr += vmap->dstart - vmap->dvma;
+	  exec_ops.to_sections[i].endaddr += vmap->dstart - vmap->dvma;
+	}
+      else if (STREQ(".bss", exec_ops.to_sections[i].the_bfd_section->name))
+	{
+	  exec_ops.to_sections[i].addr += vmap->dstart - vmap->dvma;
+	  exec_ops.to_sections[i].endaddr += vmap->dstart - vmap->dvma;
+	}
+    }
+}
+
+/* xcoff_relocate_symtab -	hook for symbol table relocation.
+   also reads shared libraries.. */
+
+void
+xcoff_relocate_symtab (pid)
+     unsigned int pid;
+{
+#define	MAX_LOAD_SEGS 64		/* maximum number of load segments */
+
+  struct ld_info *ldi;
+
+  ldi = (void *) alloca(MAX_LOAD_SEGS * sizeof (*ldi));
+
+  /* According to my humble theory, AIX has some timing problems and
+     when the user stack grows, kernel doesn't update stack info in time
+     and ptrace calls step on user stack. That is why we sleep here a little,
+     and give kernel to update its internals. */
+
+  usleep (36000);
+
+  errno = 0;
+  ptrace (PT_LDINFO, pid, (PTRACE_ARG3_TYPE) ldi,
+	  MAX_LOAD_SEGS * sizeof(*ldi), (int *) ldi);
+  if (errno)
+    perror_with_name ("ptrace ldinfo");
+
+  vmap_ldinfo (ldi);
+
+  /* relocate the exec and core sections as well. */
+  vmap_exec ();
+}
+
+/* Core file stuff.  */
+
+/* Relocate symtabs and read in shared library info, based on symbols
+   from the core file.  */
+
+void
+xcoff_relocate_core (target)
+     struct target_ops *target;
+{
+/* Offset of member MEMBER in a struct of type TYPE.  */
+#ifndef offsetof
+#define offsetof(TYPE, MEMBER) ((int) &((TYPE *)0)->MEMBER)
+#endif
+
+/* Size of a struct ld_info except for the variable-length filename.  */
+#define LDINFO_SIZE (offsetof (struct ld_info, ldinfo_filename))
+
+  sec_ptr ldinfo_sec;
+  int offset = 0;
+  struct ld_info *ldip;
+  struct vmap *vp;
+
+  /* Allocated size of buffer.  */
+  int buffer_size = LDINFO_SIZE;
+  char *buffer = xmalloc (buffer_size);
+  struct cleanup *old = make_cleanup (free_current_contents, &buffer);
+    
+  /* FIXME, this restriction should not exist.  For now, though I'll
+     avoid coredumps with error() pending a real fix.  */
+  if (vmap == NULL)
+    error
+      ("Can't debug a core file without an executable file (on the RS/6000)");
+  
+  ldinfo_sec = bfd_get_section_by_name (core_bfd, ".ldinfo");
+  if (ldinfo_sec == NULL)
+    {
+    bfd_err:
+      fprintf_filtered (gdb_stderr, "Couldn't get ldinfo from core file: %s\n",
+			bfd_errmsg (bfd_get_error ()));
+      do_cleanups (old);
+      return;
+    }
+  do
+    {
+      int i;
+      int names_found = 0;
+
+      /* Read in everything but the name.  */
+      if (bfd_get_section_contents (core_bfd, ldinfo_sec, buffer,
+				    offset, LDINFO_SIZE) == 0)
+	goto bfd_err;
+
+      /* Now the name.  */
+      i = LDINFO_SIZE;
+      do
+	{
+	  if (i == buffer_size)
+	    {
+	      buffer_size *= 2;
+	      buffer = xrealloc (buffer, buffer_size);
+	    }
+	  if (bfd_get_section_contents (core_bfd, ldinfo_sec, &buffer[i],
+					offset + i, 1) == 0)
+	    goto bfd_err;
+	  if (buffer[i++] == '\0')
+	    ++names_found;
+	} while (names_found < 2);
+
+      ldip = (struct ld_info *) buffer;
+
+      /* Can't use a file descriptor from the core file; need to open it.  */
+      ldip->ldinfo_fd = -1;
+      
+      /* The first ldinfo is for the exec file, allocated elsewhere.  */
+      if (offset == 0)
+	vp = vmap;
+      else
+	vp = add_vmap (ldip);
+
+      offset += ldip->ldinfo_next;
+
+      /* We can assume pointer == CORE_ADDR, this code is native only.  */
+      vp->tstart = (CORE_ADDR) ldip->ldinfo_textorg;
+      vp->tend = vp->tstart + ldip->ldinfo_textsize;
+      vp->dstart = (CORE_ADDR) ldip->ldinfo_dataorg;
+      vp->dend = vp->dstart + ldip->ldinfo_datasize;
+
+      /* The run time loader maps the file header in addition to the text
+	 section and returns a pointer to the header in ldinfo_textorg.
+	 Adjust the text start address to point to the real start address
+	 of the text section.  */
+      vp->tstart += vp->toffs;
+
+      /* Unless this is the exec file,
+	 add our sections to the section table for the core target.  */
+      if (vp != vmap)
+	{
+	  int count;
+	  struct section_table *stp;
+	  int update_coreops;
+
+	  /* We must update the to_sections field in the core_ops structure
+	     now to avoid dangling pointer dereferences.  */
+	  update_coreops = core_ops.to_sections == target->to_sections;
+	  
+	  count = target->to_sections_end - target->to_sections;
+	  count += 2;
+	  target->to_sections = (struct section_table *)
+	    xrealloc (target->to_sections,
+		      sizeof (struct section_table) * count);
+	  target->to_sections_end = target->to_sections + count;
+
+	  /* Update the to_sections field in the core_ops structure
+	     if needed.  */
+	  if (update_coreops)
+	    {
+	      core_ops.to_sections = target->to_sections;
+	      core_ops.to_sections_end = target->to_sections_end;
+	    }
+	  stp = target->to_sections_end - 2;
+
+	  stp->bfd = vp->bfd;
+	  stp->the_bfd_section = bfd_get_section_by_name (stp->bfd, ".text");
+	  stp->addr = vp->tstart;
+	  stp->endaddr = vp->tend;
+	  stp++;
+	  
+	  stp->bfd = vp->bfd;
+	  stp->the_bfd_section = bfd_get_section_by_name (stp->bfd, ".data");
+	  stp->addr = vp->dstart;
+	  stp->endaddr = vp->dend;
+	}
+
+      vmap_symtab (vp);
+    } while (ldip->ldinfo_next != 0);
+  vmap_exec ();
+  breakpoint_re_set ();
+  do_cleanups (old);
+}
+
+int
+kernel_u_size ()
+{
+  return (sizeof (struct user));
+}
+
+/* Under AIX, we have to pass the correct TOC pointer to a function
+   when calling functions in the inferior.
+   We try to find the relative toc offset of the objfile containing PC
+   and add the current load address of the data segment from the vmap.  */
+
+static CORE_ADDR
+find_toc_address (pc)
+     CORE_ADDR pc;
+{
+  struct vmap *vp;
+
+  for (vp = vmap; vp; vp = vp->nxt)
+    {
+      if (pc >= vp->tstart && pc < vp->tend)
+	{
+	  /* vp->objfile is only NULL for the exec file.  */
+	  return vp->dstart + get_toc_offset (vp->objfile == NULL
+					      ? symfile_objfile
+					      : vp->objfile);
+	}
+    }
+  error ("Unable to find TOC entry for pc 0x%x\n", pc);
+}
+
+/* Register that we are able to handle rs6000 core file formats. */
+
+static struct core_fns rs6000_core_fns =
+{
+  bfd_target_coff_flavour,
+  fetch_core_registers,
+  NULL
+};
+
+void
+_initialize_core_rs6000 ()
+{
+  /* Initialize hook in rs6000-tdep.c for determining the TOC address when
+     calling functions in the inferior.  */
+  find_toc_address_hook = &find_toc_address;
+
+  /* For native configurations, where this module is included, inform
+     the xcoffsolib module where it can find the function for symbol table
+     relocation at runtime. */
+  xcoff_relocate_symtab_hook = &xcoff_relocate_symtab;
+  add_core_fns (&rs6000_core_fns);
+}