Initial creation of sourceware repositorygdb-4_18-branchpoint

1 files changed, 4445 insertions, 0 deletions

diff --git a/gdb/hppa-tdep.c b/gdb/hppa-tdep.c
new file mode 100644
index 0000000..d911750
--- /dev/null
+++ b/gdb/hppa-tdep.c
@@ -0,0 +1,4445 @@
+/* Target-dependent code for the HP PA architecture, for GDB.
+   Copyright 1986, 87, 89, 90, 91, 92, 93, 94, 95, 96, 1999
+   Free Software Foundation, Inc.
+
+   Contributed by the Center for Software Science at the
+   University of Utah (pa-gdb-bugs@cs.utah.edu).
+
+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 "frame.h"
+#include "bfd.h"
+#include "inferior.h"
+#include "value.h"
+
+/* For argument passing to the inferior */
+#include "symtab.h"
+
+#ifdef USG
+#include <sys/types.h>
+#endif
+
+#include <dl.h>
+#include <sys/param.h>
+#include <signal.h>
+
+#include <sys/ptrace.h>
+#include <machine/save_state.h>
+
+#ifdef COFF_ENCAPSULATE
+#include "a.out.encap.h"
+#else
+#endif
+
+/*#include <sys/user.h>		After a.out.h  */
+#include <sys/file.h>
+#include "gdb_stat.h"
+#include "wait.h"
+
+#include "gdbcore.h"
+#include "gdbcmd.h"
+#include "target.h"
+#include "symfile.h"
+#include "objfiles.h"
+
+/* To support asking "What CPU is this?" */
+#include <unistd.h>
+
+/* To support detection of the pseudo-initial frame
+   that threads have. */
+#define THREAD_INITIAL_FRAME_SYMBOL  "__pthread_exit"
+#define THREAD_INITIAL_FRAME_SYM_LEN  sizeof(THREAD_INITIAL_FRAME_SYMBOL)
+ 
+static int extract_5_load PARAMS ((unsigned int));
+
+static unsigned extract_5R_store PARAMS ((unsigned int));
+
+static unsigned extract_5r_store PARAMS ((unsigned int));
+
+static void find_dummy_frame_regs PARAMS ((struct frame_info *,
+					   struct frame_saved_regs *));
+
+static int find_proc_framesize PARAMS ((CORE_ADDR));
+
+static int find_return_regnum PARAMS ((CORE_ADDR));
+
+struct unwind_table_entry *find_unwind_entry PARAMS ((CORE_ADDR));
+
+static int extract_17 PARAMS ((unsigned int));
+
+static unsigned deposit_21 PARAMS ((unsigned int, unsigned int));
+
+static int extract_21 PARAMS ((unsigned));
+
+static unsigned deposit_14 PARAMS ((int, unsigned int));
+
+static int extract_14 PARAMS ((unsigned));
+
+static void unwind_command PARAMS ((char *, int));
+
+static int low_sign_extend PARAMS ((unsigned int, unsigned int));
+
+static int sign_extend PARAMS ((unsigned int, unsigned int));
+
+static int restore_pc_queue PARAMS ((struct frame_saved_regs *));
+
+static int hppa_alignof PARAMS ((struct type *));
+
+/* To support multi-threading and stepping. */
+int hppa_prepare_to_proceed PARAMS (());
+
+static int prologue_inst_adjust_sp PARAMS ((unsigned long));
+
+static int is_branch PARAMS ((unsigned long));
+
+static int inst_saves_gr PARAMS ((unsigned long));
+
+static int inst_saves_fr PARAMS ((unsigned long));
+
+static int pc_in_interrupt_handler PARAMS ((CORE_ADDR));
+
+static int pc_in_linker_stub PARAMS ((CORE_ADDR));
+
+static int compare_unwind_entries PARAMS ((const void *, const void *));
+
+static void read_unwind_info PARAMS ((struct objfile *));
+
+static void internalize_unwinds PARAMS ((struct objfile *,
+					 struct unwind_table_entry *,
+					 asection *, unsigned int,
+					 unsigned int, CORE_ADDR));
+static void pa_print_registers PARAMS ((char *, int, int));
+static void pa_strcat_registers PARAMS ((char *, int, int, GDB_FILE *));
+static void pa_register_look_aside PARAMS ((char *, int, long *));
+static void pa_print_fp_reg PARAMS ((int));
+static void pa_strcat_fp_reg PARAMS ((int, GDB_FILE *, enum precision_type));
+
+typedef struct {
+  struct minimal_symbol * msym;
+  CORE_ADDR solib_handle;
+} args_for_find_stub;
+
+static CORE_ADDR cover_find_stub_with_shl_get PARAMS ((args_for_find_stub *));
+
+static int is_pa_2 = 0;  /* False */
+
+/* This is declared in symtab.c; set to 1 in hp-symtab-read.c */ 
+extern int hp_som_som_object_present;
+
+/* In breakpoint.c */
+extern int exception_catchpoints_are_fragile;
+
+/* This is defined in valops.c. */
+extern value_ptr
+find_function_in_inferior PARAMS((char *));
+
+/* Should call_function allocate stack space for a struct return?  */
+int
+hppa_use_struct_convention (gcc_p, type)
+     int gcc_p;
+     struct type *type;
+{
+  return (TYPE_LENGTH (type) > 8);
+}
+
+
+/* Routines to extract various sized constants out of hppa 
+   instructions. */
+
+/* This assumes that no garbage lies outside of the lower bits of 
+   value. */
+
+static int
+sign_extend (val, bits)
+     unsigned val, bits;
+{
+  return (int)(val >> (bits - 1) ? (-1 << bits) | val : val);
+}
+
+/* For many immediate values the sign bit is the low bit! */
+
+static int
+low_sign_extend (val, bits)
+     unsigned val, bits;
+{
+  return (int)((val & 0x1 ? (-1 << (bits - 1)) : 0) | val >> 1);
+}
+
+/* extract the immediate field from a ld{bhw}s instruction */
+
+#if 0
+
+unsigned
+get_field (val, from, to)
+     unsigned val, from, to;
+{
+  val = val >> 31 - to;
+  return val & ((1 << 32 - from) - 1);
+}
+
+unsigned
+set_field (val, from, to, new_val)
+     unsigned *val, from, to;
+{
+  unsigned mask = ~((1 << (to - from + 1)) << (31 - from));
+  return *val = *val & mask | (new_val << (31 - from));
+}
+
+/* extract a 3-bit space register number from a be, ble, mtsp or mfsp */
+
+int
+extract_3 (word)
+     unsigned word;
+{
+  return GET_FIELD (word, 18, 18) << 2 | GET_FIELD (word, 16, 17);
+}
+
+#endif
+
+static int
+extract_5_load (word)
+     unsigned word;
+{
+  return low_sign_extend (word >> 16 & MASK_5, 5);
+}
+
+#if 0
+
+/* extract the immediate field from a st{bhw}s instruction */
+
+int
+extract_5_store (word)
+     unsigned word;
+{
+  return low_sign_extend (word & MASK_5, 5);
+}
+
+#endif	/* 0 */
+       
+/* extract the immediate field from a break instruction */
+
+static unsigned
+extract_5r_store (word)
+     unsigned word;
+{
+  return (word & MASK_5);
+}
+
+/* extract the immediate field from a {sr}sm instruction */
+
+static unsigned
+extract_5R_store (word)
+     unsigned word;
+{
+  return (word >> 16 & MASK_5);
+}
+
+/* extract an 11 bit immediate field */
+
+#if 0
+
+int
+extract_11 (word)
+     unsigned word;
+{
+  return low_sign_extend (word & MASK_11, 11);
+}
+
+#endif
+
+/* extract a 14 bit immediate field */
+
+static int
+extract_14 (word)
+     unsigned word;
+{
+  return low_sign_extend (word & MASK_14, 14);
+}
+
+/* deposit a 14 bit constant in a word */
+
+static unsigned
+deposit_14 (opnd, word)
+     int opnd;
+     unsigned word;
+{
+  unsigned sign = (opnd < 0 ? 1 : 0);
+
+  return word | ((unsigned)opnd << 1 & MASK_14)  | sign;
+}
+
+/* extract a 21 bit constant */
+
+static int
+extract_21 (word)
+     unsigned word;
+{
+  int val;
+
+  word &= MASK_21;
+  word <<= 11;
+  val = GET_FIELD (word, 20, 20);
+  val <<= 11;
+  val |= GET_FIELD (word, 9, 19);
+  val <<= 2;
+  val |= GET_FIELD (word, 5, 6);
+  val <<= 5;
+  val |= GET_FIELD (word, 0, 4);
+  val <<= 2;
+  val |= GET_FIELD (word, 7, 8);
+  return sign_extend (val, 21) << 11;
+}
+
+/* deposit a 21 bit constant in a word. Although 21 bit constants are
+   usually the top 21 bits of a 32 bit constant, we assume that only
+   the low 21 bits of opnd are relevant */
+
+static unsigned
+deposit_21 (opnd, word)
+     unsigned opnd, word;
+{
+  unsigned val = 0;
+
+  val |= GET_FIELD (opnd, 11 + 14, 11 + 18);
+  val <<= 2;
+  val |= GET_FIELD (opnd, 11 + 12, 11 + 13);
+  val <<= 2;
+  val |= GET_FIELD (opnd, 11 + 19, 11 + 20);
+  val <<= 11;
+  val |= GET_FIELD (opnd, 11 + 1, 11 + 11);
+  val <<= 1;
+  val |= GET_FIELD (opnd, 11 + 0, 11 + 0);
+  return word | val;
+}
+
+/* extract a 12 bit constant from branch instructions */
+
+#if 0
+
+int
+extract_12 (word)
+     unsigned word;
+{
+  return sign_extend (GET_FIELD (word, 19, 28) |
+		      GET_FIELD (word, 29, 29) << 10 |
+		      (word & 0x1) << 11, 12) << 2;
+}
+
+/* Deposit a 17 bit constant in an instruction (like bl). */
+
+unsigned int
+deposit_17 (opnd, word)
+     unsigned opnd, word;
+{
+  word |= GET_FIELD (opnd, 15 + 0, 15 + 0); /* w */
+  word |= GET_FIELD (opnd, 15 + 1, 15 + 5) << 16; /* w1 */
+  word |= GET_FIELD (opnd, 15 + 6, 15 + 6) << 2; /* w2[10] */
+  word |= GET_FIELD (opnd, 15 + 7, 15 + 16) << 3; /* w2[0..9] */
+
+  return word;
+}
+
+#endif
+
+/* extract a 17 bit constant from branch instructions, returning the
+   19 bit signed value. */
+
+static int
+extract_17 (word)
+     unsigned word;
+{
+  return sign_extend (GET_FIELD (word, 19, 28) |
+		      GET_FIELD (word, 29, 29) << 10 |
+		      GET_FIELD (word, 11, 15) << 11 |
+		      (word & 0x1) << 16, 17) << 2;
+}
+
+
+/* Compare the start address for two unwind entries returning 1 if 
+   the first address is larger than the second, -1 if the second is
+   larger than the first, and zero if they are equal.  */
+
+static int
+compare_unwind_entries (arg1, arg2)
+     const void *arg1;
+     const void *arg2;
+{
+  const struct unwind_table_entry *a = arg1;
+  const struct unwind_table_entry *b = arg2;
+
+  if (a->region_start > b->region_start)
+    return 1;
+  else if (a->region_start < b->region_start)
+    return -1;
+  else
+    return 0;
+}
+
+static void
+internalize_unwinds (objfile, table, section, entries, size, text_offset)
+     struct objfile *objfile;
+     struct unwind_table_entry *table;
+     asection *section;
+     unsigned int entries, size;
+     CORE_ADDR text_offset;
+{
+  /* We will read the unwind entries into temporary memory, then
+     fill in the actual unwind table.  */
+  if (size > 0)
+    {
+      unsigned long tmp;
+      unsigned i;
+      char *buf = alloca (size);
+
+      bfd_get_section_contents (objfile->obfd, section, buf, 0, size);
+
+      /* Now internalize the information being careful to handle host/target
+	 endian issues.  */
+      for (i = 0; i < entries; i++)
+	{
+	  table[i].region_start = bfd_get_32 (objfile->obfd,
+					      (bfd_byte *)buf);
+	  table[i].region_start += text_offset;
+	  buf += 4;
+	  table[i].region_end = bfd_get_32 (objfile->obfd, (bfd_byte *)buf);
+	  table[i].region_end += text_offset;
+	  buf += 4;
+	  tmp = bfd_get_32 (objfile->obfd, (bfd_byte *)buf);
+	  buf += 4;
+	  table[i].Cannot_unwind = (tmp >> 31) & 0x1;
+	  table[i].Millicode = (tmp >> 30) & 0x1;
+	  table[i].Millicode_save_sr0 = (tmp >> 29) & 0x1;
+	  table[i].Region_description = (tmp >> 27) & 0x3;
+	  table[i].reserved1 = (tmp >> 26) & 0x1;
+	  table[i].Entry_SR = (tmp >> 25) & 0x1;
+	  table[i].Entry_FR = (tmp >> 21) & 0xf;
+	  table[i].Entry_GR = (tmp >> 16) & 0x1f;
+	  table[i].Args_stored = (tmp >> 15) & 0x1;
+	  table[i].Variable_Frame = (tmp >> 14) & 0x1;
+	  table[i].Separate_Package_Body = (tmp >> 13) & 0x1;
+	  table[i].Frame_Extension_Millicode = (tmp >> 12) & 0x1;
+	  table[i].Stack_Overflow_Check = (tmp >> 11) & 0x1;
+	  table[i].Two_Instruction_SP_Increment = (tmp >> 10) & 0x1;
+	  table[i].Ada_Region = (tmp >> 9) & 0x1;
+	  table[i].cxx_info = (tmp >> 8) & 0x1;
+	  table[i].cxx_try_catch = (tmp >> 7) & 0x1;
+	  table[i].sched_entry_seq = (tmp >> 6) & 0x1;
+	  table[i].reserved2 = (tmp >> 5) & 0x1;
+	  table[i].Save_SP = (tmp >> 4) & 0x1;
+	  table[i].Save_RP = (tmp >> 3) & 0x1;
+	  table[i].Save_MRP_in_frame = (tmp >> 2) & 0x1;
+	  table[i].extn_ptr_defined = (tmp >> 1) & 0x1;
+	  table[i].Cleanup_defined = tmp & 0x1;
+	  tmp = bfd_get_32 (objfile->obfd, (bfd_byte *)buf);
+	  buf += 4;
+	  table[i].MPE_XL_interrupt_marker = (tmp >> 31) & 0x1;
+	  table[i].HP_UX_interrupt_marker = (tmp >> 30) & 0x1;
+	  table[i].Large_frame = (tmp >> 29) & 0x1;
+	  table[i].Pseudo_SP_Set = (tmp >> 28) & 0x1;
+	  table[i].reserved4 = (tmp >> 27) & 0x1;
+	  table[i].Total_frame_size = tmp & 0x7ffffff;
+
+          /* Stub unwinds are handled elsewhere. */
+	  table[i].stub_unwind.stub_type = 0;
+	  table[i].stub_unwind.padding = 0;
+	}
+    }
+}
+
+/* Read in the backtrace information stored in the `$UNWIND_START$' section of
+   the object file.  This info is used mainly by find_unwind_entry() to find
+   out the stack frame size and frame pointer used by procedures.  We put
+   everything on the psymbol obstack in the objfile so that it automatically
+   gets freed when the objfile is destroyed.  */
+
+static void
+read_unwind_info (objfile)
+     struct objfile *objfile;
+{
+  asection *unwind_sec, *elf_unwind_sec, *stub_unwind_sec;
+  unsigned unwind_size, elf_unwind_size, stub_unwind_size, total_size;
+  unsigned index, unwind_entries, elf_unwind_entries;
+  unsigned stub_entries, total_entries;
+  CORE_ADDR text_offset;
+  struct obj_unwind_info *ui;
+  obj_private_data_t *obj_private;
+
+  text_offset = ANOFFSET (objfile->section_offsets, 0);
+  ui = (struct obj_unwind_info *)obstack_alloc (&objfile->psymbol_obstack,
+						sizeof (struct obj_unwind_info));
+
+  ui->table = NULL;
+  ui->cache = NULL;
+  ui->last = -1;
+
+  /* Get hooks to all unwind sections.   Note there is no linker-stub unwind
+     section in ELF at the moment.  */
+  unwind_sec = bfd_get_section_by_name (objfile->obfd, "$UNWIND_START$");
+  elf_unwind_sec = bfd_get_section_by_name (objfile->obfd, ".PARISC.unwind");
+  stub_unwind_sec = bfd_get_section_by_name (objfile->obfd, "$UNWIND_END$");
+
+  /* Get sizes and unwind counts for all sections.  */
+  if (unwind_sec)
+    {
+      unwind_size = bfd_section_size (objfile->obfd, unwind_sec);
+      unwind_entries = unwind_size / UNWIND_ENTRY_SIZE;
+    }
+  else
+    {
+      unwind_size = 0;
+      unwind_entries = 0;
+    }
+
+  if (elf_unwind_sec)
+    {
+      elf_unwind_size = bfd_section_size (objfile->obfd, elf_unwind_sec); /* purecov: deadcode */
+      elf_unwind_entries = elf_unwind_size / UNWIND_ENTRY_SIZE; /* purecov: deadcode */
+    }
+  else
+    {
+      elf_unwind_size = 0;
+      elf_unwind_entries = 0;
+    }
+
+  if (stub_unwind_sec)
+    {
+      stub_unwind_size = bfd_section_size (objfile->obfd, stub_unwind_sec);
+      stub_entries = stub_unwind_size / STUB_UNWIND_ENTRY_SIZE;
+    }
+  else
+    {
+      stub_unwind_size = 0;
+      stub_entries = 0;
+    }
+
+  /* Compute total number of unwind entries and their total size.  */
+  total_entries = unwind_entries + elf_unwind_entries + stub_entries;
+  total_size = total_entries * sizeof (struct unwind_table_entry);
+
+  /* Allocate memory for the unwind table.  */
+  ui->table = (struct unwind_table_entry *)
+    obstack_alloc (&objfile->psymbol_obstack, total_size);
+   ui->last = total_entries - 1;
+
+  /* Internalize the standard unwind entries.  */
+  index = 0;
+  internalize_unwinds (objfile, &ui->table[index], unwind_sec,
+		       unwind_entries, unwind_size, text_offset);
+  index += unwind_entries;
+  internalize_unwinds (objfile, &ui->table[index], elf_unwind_sec,
+		       elf_unwind_entries, elf_unwind_size, text_offset);
+  index += elf_unwind_entries;
+
+  /* Now internalize the stub unwind entries.  */
+  if (stub_unwind_size > 0)
+    {
+      unsigned int i;
+      char *buf = alloca (stub_unwind_size);
+
+      /* Read in the stub unwind entries.  */
+      bfd_get_section_contents (objfile->obfd, stub_unwind_sec, buf,
+				0, stub_unwind_size);
+
+      /* Now convert them into regular unwind entries.  */
+      for (i = 0; i < stub_entries; i++, index++)
+	{
+	  /* Clear out the next unwind entry.  */
+	  memset (&ui->table[index], 0, sizeof (struct unwind_table_entry));
+
+	  /* Convert offset & size into region_start and region_end.  
+	     Stuff away the stub type into "reserved" fields.  */
+	  ui->table[index].region_start = bfd_get_32 (objfile->obfd,
+						      (bfd_byte *) buf);
+	  ui->table[index].region_start += text_offset;
+	  buf += 4;
+	  ui->table[index].stub_unwind.stub_type = bfd_get_8 (objfile->obfd,
+                                                              (bfd_byte *) buf);
+	  buf += 2;
+	  ui->table[index].region_end
+	    = ui->table[index].region_start + 4 * 
+	      (bfd_get_16 (objfile->obfd, (bfd_byte *) buf) - 1);
+	  buf += 2;
+	}
+
+    }
+
+  /* Unwind table needs to be kept sorted.  */
+  qsort (ui->table, total_entries, sizeof (struct unwind_table_entry),
+	 compare_unwind_entries);
+
+  /* Keep a pointer to the unwind information.  */
+  if(objfile->obj_private == NULL)
+    {
+      obj_private = (obj_private_data_t *)
+	obstack_alloc(&objfile->psymbol_obstack,
+		      sizeof(obj_private_data_t));
+      obj_private->unwind_info = NULL;
+      obj_private->so_info     = NULL;
+      
+      objfile->obj_private = (PTR) obj_private;
+    }
+  obj_private = (obj_private_data_t *)objfile->obj_private; 
+  obj_private->unwind_info = ui;
+}
+
+/* Lookup the unwind (stack backtrace) info for the given PC.  We search all
+   of the objfiles seeking the unwind table entry for this PC.  Each objfile
+   contains a sorted list of struct unwind_table_entry.  Since we do a binary
+   search of the unwind tables, we depend upon them to be sorted.  */
+
+struct unwind_table_entry *
+find_unwind_entry(pc)
+     CORE_ADDR pc;
+{
+  int first, middle, last;
+  struct objfile *objfile;
+
+  /* A function at address 0?  Not in HP-UX! */
+  if (pc == (CORE_ADDR) 0)
+    return NULL;
+
+  ALL_OBJFILES (objfile)
+    {
+      struct obj_unwind_info *ui;
+      ui = NULL;
+      if (objfile->obj_private)
+	ui = ((obj_private_data_t *)(objfile->obj_private))->unwind_info;
+
+      if (!ui)
+	{
+	  read_unwind_info (objfile);
+	  if (objfile->obj_private == NULL)
+	    error ("Internal error reading unwind information."); /* purecov: deadcode */
+	  ui = ((obj_private_data_t *)(objfile->obj_private))->unwind_info;
+	}
+
+      /* First, check the cache */
+
+      if (ui->cache
+	  && pc >= ui->cache->region_start
+	  && pc <= ui->cache->region_end)
+	return ui->cache;
+
+      /* Not in the cache, do a binary search */
+
+      first = 0;
+      last = ui->last;
+
+      while (first <= last)
+	{
+	  middle = (first + last) / 2;
+	  if (pc >= ui->table[middle].region_start
+	      && pc <= ui->table[middle].region_end)
+	    {
+	      ui->cache = &ui->table[middle];
+	      return &ui->table[middle];
+	    }
+
+	  if (pc < ui->table[middle].region_start)
+	    last = middle - 1;
+	  else
+	    first = middle + 1;
+	}
+    }				/* ALL_OBJFILES() */
+  return NULL;
+}
+
+/* Return the adjustment necessary to make for addresses on the stack
+   as presented by hpread.c.
+
+   This is necessary because of the stack direction on the PA and the
+   bizarre way in which someone (?) decided they wanted to handle
+   frame pointerless code in GDB.  */
+int
+hpread_adjust_stack_address (func_addr)
+     CORE_ADDR func_addr;
+{
+  struct unwind_table_entry *u;
+
+  u = find_unwind_entry (func_addr);
+  if (!u)
+    return 0;
+  else
+    return u->Total_frame_size << 3;
+}
+
+/* Called to determine if PC is in an interrupt handler of some
+   kind.  */
+
+static int
+pc_in_interrupt_handler (pc)
+     CORE_ADDR pc;
+{
+  struct unwind_table_entry *u;
+  struct minimal_symbol *msym_us;
+
+  u = find_unwind_entry (pc);
+  if (!u)
+    return 0;
+
+  /* Oh joys.  HPUX sets the interrupt bit for _sigreturn even though
+     its frame isn't a pure interrupt frame.  Deal with this.  */
+  msym_us = lookup_minimal_symbol_by_pc (pc);
+
+  return u->HP_UX_interrupt_marker && !IN_SIGTRAMP (pc, SYMBOL_NAME (msym_us));
+}
+
+/* Called when no unwind descriptor was found for PC.  Returns 1 if it
+   appears that PC is in a linker stub.  */
+
+static int
+pc_in_linker_stub (pc)
+     CORE_ADDR pc;
+{
+  int found_magic_instruction = 0;
+  int i;
+  char buf[4];
+
+  /* If unable to read memory, assume pc is not in a linker stub.  */
+  if (target_read_memory (pc, buf, 4) != 0)
+    return 0;
+
+  /* We are looking for something like
+
+     ; $$dyncall jams RP into this special spot in the frame (RP')
+     ; before calling the "call stub"
+     ldw     -18(sp),rp
+
+     ldsid   (rp),r1         ; Get space associated with RP into r1
+     mtsp    r1,sp           ; Move it into space register 0
+     be,n    0(sr0),rp)      ; back to your regularly scheduled program */
+
+  /* Maximum known linker stub size is 4 instructions.  Search forward
+     from the given PC, then backward.  */
+  for (i = 0; i < 4; i++)
+    {
+      /* If we hit something with an unwind, stop searching this direction.  */
+
+      if (find_unwind_entry (pc + i * 4) != 0)
+	break;
+
+      /* Check for ldsid (rp),r1 which is the magic instruction for a 
+	 return from a cross-space function call.  */
+      if (read_memory_integer (pc + i * 4, 4) == 0x004010a1)
+	{
+	  found_magic_instruction = 1;
+	  break;
+	}
+      /* Add code to handle long call/branch and argument relocation stubs
+	 here.  */
+    }
+
+  if (found_magic_instruction != 0)
+    return 1;
+
+  /* Now look backward.  */
+  for (i = 0; i < 4; i++)
+    {
+      /* If we hit something with an unwind, stop searching this direction.  */
+
+      if (find_unwind_entry (pc - i * 4) != 0)
+	break;
+
+      /* Check for ldsid (rp),r1 which is the magic instruction for a 
+	 return from a cross-space function call.  */
+      if (read_memory_integer (pc - i * 4, 4) == 0x004010a1)
+	{
+	  found_magic_instruction = 1;
+	  break;
+	}
+      /* Add code to handle long call/branch and argument relocation stubs
+	 here.  */
+    }
+  return found_magic_instruction;
+}
+
+static int
+find_return_regnum(pc)
+     CORE_ADDR pc;
+{
+  struct unwind_table_entry *u;
+
+  u = find_unwind_entry (pc);
+
+  if (!u)
+    return RP_REGNUM;
+
+  if (u->Millicode)
+    return 31;
+
+  return RP_REGNUM;
+}
+
+/* Return size of frame, or -1 if we should use a frame pointer.  */
+static int
+find_proc_framesize (pc)
+     CORE_ADDR pc;
+{
+  struct unwind_table_entry *u;
+  struct minimal_symbol *msym_us;
+
+  /* This may indicate a bug in our callers... */
+  if (pc == (CORE_ADDR)0)
+    return -1;
+  
+  u = find_unwind_entry (pc);
+
+  if (!u)
+    {
+      if (pc_in_linker_stub (pc))
+	/* Linker stubs have a zero size frame.  */
+	return 0;
+      else
+	return -1;
+    }
+
+  msym_us = lookup_minimal_symbol_by_pc (pc);
+
+  /* If Save_SP is set, and we're not in an interrupt or signal caller,
+     then we have a frame pointer.  Use it.  */
+  if (u->Save_SP && !pc_in_interrupt_handler (pc)
+      && !IN_SIGTRAMP (pc, SYMBOL_NAME (msym_us)))
+    return -1;
+
+  return u->Total_frame_size << 3;
+}
+
+/* Return offset from sp at which rp is saved, or 0 if not saved.  */
+static int rp_saved PARAMS ((CORE_ADDR));
+
+static int
+rp_saved (pc)
+     CORE_ADDR pc;
+{
+  struct unwind_table_entry *u;
+
+  /* A function at, and thus a return PC from, address 0?  Not in HP-UX! */
+  if (pc == (CORE_ADDR) 0)
+    return 0;
+
+  u = find_unwind_entry (pc);
+
+  if (!u)
+    {
+      if (pc_in_linker_stub (pc))
+	/* This is the so-called RP'.  */
+	return -24;
+      else
+	return 0;
+    }
+
+  if (u->Save_RP)
+    return -20;
+  else if (u->stub_unwind.stub_type != 0)
+    {
+      switch (u->stub_unwind.stub_type)
+	{
+	case EXPORT:
+	case IMPORT:
+	  return -24;
+	case PARAMETER_RELOCATION:
+	  return -8;
+	default:
+	  return 0;
+	}
+    }
+  else
+    return 0;
+}
+
+int
+frameless_function_invocation (frame)
+     struct frame_info *frame;
+{
+  struct unwind_table_entry *u;
+
+  u = find_unwind_entry (frame->pc);
+
+  if (u == 0)
+    return 0;
+
+  return (u->Total_frame_size == 0 && u->stub_unwind.stub_type == 0);
+}
+
+CORE_ADDR
+saved_pc_after_call (frame)
+     struct frame_info *frame;
+{
+  int ret_regnum;
+  CORE_ADDR pc;
+  struct unwind_table_entry *u;
+
+  ret_regnum = find_return_regnum (get_frame_pc (frame));
+  pc = read_register (ret_regnum) & ~0x3;
+  
+  /* If PC is in a linker stub, then we need to dig the address
+     the stub will return to out of the stack.  */
+  u = find_unwind_entry (pc);
+  if (u && u->stub_unwind.stub_type != 0)
+    return FRAME_SAVED_PC (frame);
+  else
+    return pc;
+}
+
+CORE_ADDR
+hppa_frame_saved_pc (frame)
+     struct frame_info *frame;
+{
+  CORE_ADDR pc = get_frame_pc (frame);
+  struct unwind_table_entry *u;
+  CORE_ADDR old_pc;
+  int  spun_around_loop = 0;
+  int  rp_offset = 0;
+
+  /* BSD, HPUX & OSF1 all lay out the hardware state in the same manner
+     at the base of the frame in an interrupt handler.  Registers within
+     are saved in the exact same order as GDB numbers registers.  How
+     convienent.  */
+  if (pc_in_interrupt_handler (pc))
+    return read_memory_integer (frame->frame + PC_REGNUM * 4, 4) & ~0x3;
+
+#ifdef FRAME_SAVED_PC_IN_SIGTRAMP
+  /* Deal with signal handler caller frames too.  */
+  if (frame->signal_handler_caller)
+    {
+      CORE_ADDR rp;
+      FRAME_SAVED_PC_IN_SIGTRAMP (frame, &rp);
+      return rp & ~0x3;
+    }
+#endif
+
+  if (frameless_function_invocation (frame))
+    {
+      int ret_regnum;
+
+      ret_regnum = find_return_regnum (pc);
+
+      /* If the next frame is an interrupt frame or a signal
+	 handler caller, then we need to look in the saved
+	 register area to get the return pointer (the values
+	 in the registers may not correspond to anything useful).  */
+      if (frame->next 
+	  && (frame->next->signal_handler_caller
+	      || pc_in_interrupt_handler (frame->next->pc)))
+	{
+	  struct frame_saved_regs saved_regs;
+
+	  get_frame_saved_regs (frame->next, &saved_regs);
+	  if (read_memory_integer (saved_regs.regs[FLAGS_REGNUM], 4) & 0x2)
+	    {
+	      pc = read_memory_integer (saved_regs.regs[31], 4) & ~0x3;
+
+	      /* Syscalls are really two frames.  The syscall stub itself
+		 with a return pointer in %rp and the kernel call with
+		 a return pointer in %r31.  We return the %rp variant
+		 if %r31 is the same as frame->pc.  */
+	      if (pc == frame->pc)
+		pc = read_memory_integer (saved_regs.regs[RP_REGNUM], 4) & ~0x3;
+	    }
+	  else
+	    pc = read_memory_integer (saved_regs.regs[RP_REGNUM], 4) & ~0x3;
+	}
+      else
+	pc = read_register (ret_regnum) & ~0x3;
+    }
+  else
+    {
+      spun_around_loop = 0;
+      old_pc           = pc;
+
+restart:
+      rp_offset = rp_saved (pc);
+
+      /* Similar to code in frameless function case.  If the next
+	 frame is a signal or interrupt handler, then dig the right
+	 information out of the saved register info.  */
+      if (rp_offset == 0
+	  && frame->next
+	  && (frame->next->signal_handler_caller
+	      || pc_in_interrupt_handler (frame->next->pc)))
+	{
+	  struct frame_saved_regs saved_regs;
+
+	  get_frame_saved_regs (frame->next, &saved_regs);
+	  if (read_memory_integer (saved_regs.regs[FLAGS_REGNUM], 4) & 0x2)
+	    {
+	      pc = read_memory_integer (saved_regs.regs[31], 4) & ~0x3;
+
+	      /* Syscalls are really two frames.  The syscall stub itself
+		 with a return pointer in %rp and the kernel call with
+		 a return pointer in %r31.  We return the %rp variant
+		 if %r31 is the same as frame->pc.  */
+	      if (pc == frame->pc)
+		pc = read_memory_integer (saved_regs.regs[RP_REGNUM], 4) & ~0x3;
+	    }
+	  else
+	    pc = read_memory_integer (saved_regs.regs[RP_REGNUM], 4) & ~0x3;
+	}
+      else if (rp_offset == 0)
+        {
+          old_pc = pc;
+          pc = read_register (RP_REGNUM) & ~0x3;
+        }
+      else
+        {
+          old_pc = pc;
+          pc = read_memory_integer (frame->frame + rp_offset, 4) & ~0x3;
+        }
+    }
+
+  /* If PC is inside a linker stub, then dig out the address the stub
+     will return to. 
+
+     Don't do this for long branch stubs.  Why?  For some unknown reason
+     _start is marked as a long branch stub in hpux10.  */
+  u = find_unwind_entry (pc);
+  if (u && u->stub_unwind.stub_type != 0
+      && u->stub_unwind.stub_type != LONG_BRANCH)
+    {
+      unsigned int insn;
+
+      /* If this is a dynamic executable, and we're in a signal handler,
+	 then the call chain will eventually point us into the stub for
+	 _sigreturn.  Unlike most cases, we'll be pointed to the branch
+	 to the real sigreturn rather than the code after the real branch!. 
+
+	 Else, try to dig the address the stub will return to in the normal
+	 fashion.  */
+      insn = read_memory_integer (pc, 4);
+      if ((insn & 0xfc00e000) == 0xe8000000)
+	return (pc + extract_17 (insn) + 8) & ~0x3;
+      else
+	{
+        if (old_pc == pc)
+            spun_around_loop++;
+        
+        if (spun_around_loop > 1) 
+	  {
+           /* We're just about to go around the loop again with
+              no more hope of success.  Die. */
+           error("Unable to find return pc for this frame");
+	  }
+        else
+	  goto restart;
+	}
+    }
+
+  return pc;
+}
+
+/* We need to correct the PC and the FP for the outermost frame when we are
+   in a system call.  */
+
+void
+init_extra_frame_info (fromleaf, frame)
+     int fromleaf;
+     struct frame_info *frame;
+{
+  int flags;
+  int framesize;
+
+  if (frame->next && !fromleaf)
+    return;
+
+  /* If the next frame represents a frameless function invocation
+     then we have to do some adjustments that are normally done by
+     FRAME_CHAIN.  (FRAME_CHAIN is not called in this case.)  */
+  if (fromleaf)
+    {
+      /* Find the framesize of *this* frame without peeking at the PC
+	 in the current frame structure (it isn't set yet).  */
+      framesize = find_proc_framesize (FRAME_SAVED_PC (get_next_frame (frame)));
+
+      /* Now adjust our base frame accordingly.  If we have a frame pointer
+	 use it, else subtract the size of this frame from the current
+	 frame.  (we always want frame->frame to point at the lowest address
+	 in the frame).  */
+      if (framesize == -1)
+	frame->frame = TARGET_READ_FP ();
+      else
+	frame->frame -= framesize;
+      return;
+    }
+
+  flags = read_register (FLAGS_REGNUM);
+  if (flags & 2)	/* In system call? */
+    frame->pc = read_register (31) & ~0x3;
+
+  /* The outermost frame is always derived from PC-framesize
+
+     One might think frameless innermost frames should have
+     a frame->frame that is the same as the parent's frame->frame.
+     That is wrong; frame->frame in that case should be the *high*
+     address of the parent's frame.  It's complicated as hell to
+     explain, but the parent *always* creates some stack space for
+     the child.  So the child actually does have a frame of some
+     sorts, and its base is the high address in its parent's frame.  */
+  framesize = find_proc_framesize(frame->pc);
+  if (framesize == -1)
+    frame->frame = TARGET_READ_FP ();
+  else
+    frame->frame = read_register (SP_REGNUM) - framesize;
+}
+
+/* Given a GDB frame, determine the address of the calling function's frame.
+   This will be used to create a new GDB frame struct, and then
+   INIT_EXTRA_FRAME_INFO and INIT_FRAME_PC will be called for the new frame.
+
+   This may involve searching through prologues for several functions
+   at boundaries where GCC calls HP C code, or where code which has
+   a frame pointer calls code without a frame pointer.  */
+
+CORE_ADDR
+frame_chain (frame)
+     struct frame_info *frame;
+{
+  int my_framesize, caller_framesize;
+  struct unwind_table_entry *u;
+  CORE_ADDR frame_base;
+  struct frame_info *tmp_frame;
+
+  CORE_ADDR  caller_pc;
+
+  struct minimal_symbol *min_frame_symbol;
+  struct symbol         *frame_symbol;
+  char                  *frame_symbol_name;
+
+  /* If this is a threaded application, and we see the
+     routine "__pthread_exit", treat it as the stack root
+     for this thread. */
+  min_frame_symbol  = lookup_minimal_symbol_by_pc (frame->pc);
+  frame_symbol      = find_pc_function(frame->pc);
+
+  if ((min_frame_symbol != 0) /* && (frame_symbol == 0) */)
+    {
+    /* The test above for "no user function name" would defend
+       against the slim likelihood that a user might define a
+       routine named "__pthread_exit" and then try to debug it.
+
+       If it weren't commented out, and you tried to debug the
+       pthread library itself, you'd get errors.
+      
+       So for today, we don't make that check. */
+    frame_symbol_name = SYMBOL_NAME(min_frame_symbol);
+    if (frame_symbol_name != 0) {
+      if (0 == strncmp(frame_symbol_name,
+		       THREAD_INITIAL_FRAME_SYMBOL,
+		       THREAD_INITIAL_FRAME_SYM_LEN)) {
+         /* Pretend we've reached the bottom of the stack. */
+         return (CORE_ADDR) 0;
+         }
+       }  
+    }  /* End of hacky code for threads. */
+    
+  /* Handle HPUX, BSD, and OSF1 style interrupt frames first.  These
+     are easy; at *sp we have a full save state strucutre which we can
+     pull the old stack pointer from.  Also see frame_saved_pc for
+     code to dig a saved PC out of the save state structure.  */
+  if (pc_in_interrupt_handler (frame->pc))
+    frame_base = read_memory_integer (frame->frame + SP_REGNUM * 4, 4);
+#ifdef FRAME_BASE_BEFORE_SIGTRAMP
+  else if (frame->signal_handler_caller)
+    {
+      FRAME_BASE_BEFORE_SIGTRAMP (frame, &frame_base);
+    }
+#endif
+  else
+    frame_base = frame->frame;
+
+  /* Get frame sizes for the current frame and the frame of the 
+     caller.  */
+  my_framesize = find_proc_framesize (frame->pc);
+  caller_pc = FRAME_SAVED_PC(frame);
+
+  /* If we can't determine the caller's PC, then it's not likely we can
+     really determine anything meaningful about its frame.  We'll consider
+     this to be stack bottom. */
+  if (caller_pc == (CORE_ADDR) 0)
+    return (CORE_ADDR) 0;
+
+  caller_framesize = find_proc_framesize (FRAME_SAVED_PC(frame));
+
+  /* If caller does not have a frame pointer, then its frame
+     can be found at current_frame - caller_framesize.  */
+  if (caller_framesize != -1)
+    {
+      return frame_base - caller_framesize;
+    }
+  /* Both caller and callee have frame pointers and are GCC compiled
+     (SAVE_SP bit in unwind descriptor is on for both functions.
+     The previous frame pointer is found at the top of the current frame.  */
+  if (caller_framesize == -1 && my_framesize == -1)
+    {
+      return read_memory_integer (frame_base, 4);
+    }
+  /* Caller has a frame pointer, but callee does not.  This is a little
+     more difficult as GCC and HP C lay out locals and callee register save
+     areas very differently.
+
+     The previous frame pointer could be in a register, or in one of 
+     several areas on the stack.
+
+     Walk from the current frame to the innermost frame examining 
+     unwind descriptors to determine if %r3 ever gets saved into the
+     stack.  If so return whatever value got saved into the stack.
+     If it was never saved in the stack, then the value in %r3 is still
+     valid, so use it. 
+
+     We use information from unwind descriptors to determine if %r3
+     is saved into the stack (Entry_GR field has this information).  */
+
+  tmp_frame = frame;
+  while (tmp_frame)
+    {
+      u = find_unwind_entry (tmp_frame->pc);
+
+      if (!u)
+	{
+	  /* We could find this information by examining prologues.  I don't
+	     think anyone has actually written any tools (not even "strip")
+	     which leave them out of an executable, so maybe this is a moot
+	     point.  */
+          /* ??rehrauer: Actually, it's quite possible to stepi your way into
+             code that doesn't have unwind entries.  For example, stepping into
+             the dynamic linker will give you a PC that has none.  Thus, I've
+             disabled this warning. */
+#if 0
+	  warning ("Unable to find unwind for PC 0x%x -- Help!", tmp_frame->pc);
+#endif
+	  return (CORE_ADDR) 0;
+	}
+
+      /* Entry_GR specifies the number of callee-saved general registers
+	 saved in the stack.  It starts at %r3, so %r3 would be 1.  */
+      if (u->Entry_GR >= 1 || u->Save_SP
+	  || tmp_frame->signal_handler_caller
+	  || pc_in_interrupt_handler (tmp_frame->pc))
+	break;
+      else
+	tmp_frame = tmp_frame->next;
+    }
+
+  if (tmp_frame)
+    {
+      /* We may have walked down the chain into a function with a frame
+	 pointer.  */
+      if (u->Save_SP
+	  && !tmp_frame->signal_handler_caller
+	  && !pc_in_interrupt_handler (tmp_frame->pc))
+	{
+	  return read_memory_integer (tmp_frame->frame, 4);
+	}
+      /* %r3 was saved somewhere in the stack.  Dig it out.  */
+      else 
+	{
+	  struct frame_saved_regs saved_regs;
+
+	  /* Sick.
+
+	     For optimization purposes many kernels don't have the
+	     callee saved registers into the save_state structure upon
+	     entry into the kernel for a syscall; the optimization
+	     is usually turned off if the process is being traced so
+	     that the debugger can get full register state for the
+	     process.
+	      
+	     This scheme works well except for two cases:
+
+	       * Attaching to a process when the process is in the
+	       kernel performing a system call (debugger can't get
+	       full register state for the inferior process since
+	       the process wasn't being traced when it entered the
+	       system call).
+
+	       * Register state is not complete if the system call
+	       causes the process to core dump.
+
+
+	     The following heinous code is an attempt to deal with
+	     the lack of register state in a core dump.  It will
+	     fail miserably if the function which performs the
+	     system call has a variable sized stack frame.  */
+
+	  get_frame_saved_regs (tmp_frame, &saved_regs);
+
+	  /* Abominable hack.  */
+	  if (current_target.to_has_execution == 0
+	      && ((saved_regs.regs[FLAGS_REGNUM]
+	           && (read_memory_integer (saved_regs.regs[FLAGS_REGNUM], 4)
+		       & 0x2))
+		  || (saved_regs.regs[FLAGS_REGNUM] == 0
+		      && read_register (FLAGS_REGNUM) & 0x2)))
+	    {
+	      u = find_unwind_entry (FRAME_SAVED_PC (frame));
+	      if (!u)
+		{
+		  return read_memory_integer (saved_regs.regs[FP_REGNUM], 4);
+		}
+	      else
+		{
+		  return frame_base - (u->Total_frame_size << 3);
+		}
+	    }
+	
+	  return read_memory_integer (saved_regs.regs[FP_REGNUM], 4);
+	}
+    }
+  else
+    {
+      struct frame_saved_regs saved_regs;
+
+      /* Get the innermost frame.  */
+      tmp_frame = frame;
+      while (tmp_frame->next != NULL)
+	tmp_frame = tmp_frame->next;
+
+      get_frame_saved_regs (tmp_frame, &saved_regs);
+      /* Abominable hack.  See above.  */
+      if (current_target.to_has_execution == 0
+	  && ((saved_regs.regs[FLAGS_REGNUM]
+	       && (read_memory_integer (saved_regs.regs[FLAGS_REGNUM], 4)
+		   & 0x2))
+	      || (saved_regs.regs[FLAGS_REGNUM] == 0
+		  && read_register (FLAGS_REGNUM)  & 0x2)))
+	{
+	  u = find_unwind_entry (FRAME_SAVED_PC (frame));
+	  if (!u)
+	    {
+	      return read_memory_integer (saved_regs.regs[FP_REGNUM], 4);
+	    }
+	   else
+	     {
+	       return frame_base - (u->Total_frame_size << 3);
+	     }
+	}
+	
+      /* The value in %r3 was never saved into the stack (thus %r3 still
+	 holds the value of the previous frame pointer).  */
+      return TARGET_READ_FP ();
+    }
+}
+
+
+/* To see if a frame chain is valid, see if the caller looks like it
+   was compiled with gcc. */
+
+int
+hppa_frame_chain_valid (chain, thisframe)
+     CORE_ADDR chain;
+     struct frame_info *thisframe;
+{
+  struct minimal_symbol *msym_us;
+  struct minimal_symbol *msym_start;
+  struct unwind_table_entry *u, *next_u = NULL;
+  struct frame_info *next;
+
+  if (!chain)
+    return 0;
+
+  u = find_unwind_entry (thisframe->pc);
+
+  if (u == NULL)
+    return 1;
+
+  /* We can't just check that the same of msym_us is "_start", because
+     someone idiotically decided that they were going to make a Ltext_end
+     symbol with the same address.  This Ltext_end symbol is totally
+     indistinguishable (as nearly as I can tell) from the symbol for a function
+     which is (legitimately, since it is in the user's namespace)
+     named Ltext_end, so we can't just ignore it.  */
+  msym_us = lookup_minimal_symbol_by_pc (FRAME_SAVED_PC (thisframe));
+  msym_start = lookup_minimal_symbol ("_start", NULL, NULL);
+  if (msym_us
+      && msym_start
+      && SYMBOL_VALUE_ADDRESS (msym_us) == SYMBOL_VALUE_ADDRESS (msym_start))
+    return 0;
+
+  /* Grrrr.  Some new idiot decided that they don't want _start for the
+     PRO configurations; $START$ calls main directly....  Deal with it.  */
+  msym_start = lookup_minimal_symbol ("$START$", NULL, NULL);
+  if (msym_us
+      && msym_start
+      && SYMBOL_VALUE_ADDRESS (msym_us) == SYMBOL_VALUE_ADDRESS (msym_start))
+    return 0;
+
+  next = get_next_frame (thisframe);
+  if (next)
+    next_u = find_unwind_entry (next->pc);
+
+  /* If this frame does not save SP, has no stack, isn't a stub,
+     and doesn't "call" an interrupt routine or signal handler caller,
+     then its not valid.  */
+  if (u->Save_SP || u->Total_frame_size || u->stub_unwind.stub_type != 0
+      || (thisframe->next && thisframe->next->signal_handler_caller)
+      || (next_u && next_u->HP_UX_interrupt_marker))
+    return 1;
+
+  if (pc_in_linker_stub (thisframe->pc))
+    return 1;
+
+  return 0;
+}
+
+/*
+   These functions deal with saving and restoring register state
+   around a function call in the inferior. They keep the stack
+   double-word aligned; eventually, on an hp700, the stack will have
+   to be aligned to a 64-byte boundary. */
+
+void
+push_dummy_frame (inf_status)
+     struct inferior_status *inf_status;
+{
+  CORE_ADDR sp, pc, pcspace;
+  register int regnum;
+  int int_buffer;
+  double freg_buffer;
+
+  /* Oh, what a hack.  If we're trying to perform an inferior call
+     while the inferior is asleep, we have to make sure to clear
+     the "in system call" bit in the flag register (the call will
+     start after the syscall returns, so we're no longer in the system
+     call!)  This state is kept in "inf_status", change it there.
+
+     We also need a number of horrid hacks to deal with lossage in the
+     PC queue registers (apparently they're not valid when the in syscall
+     bit is set).  */
+  pc = target_read_pc (inferior_pid);
+  int_buffer = read_register (FLAGS_REGNUM);
+  if (int_buffer & 0x2)
+    {
+      unsigned int sid;
+      int_buffer &= ~0x2;
+      memcpy (inf_status->registers, &int_buffer, 4);
+      memcpy (inf_status->registers + REGISTER_BYTE (PCOQ_HEAD_REGNUM), &pc, 4);
+      pc += 4;
+      memcpy (inf_status->registers + REGISTER_BYTE (PCOQ_TAIL_REGNUM), &pc, 4);
+      pc -= 4;
+      sid = (pc >> 30) & 0x3;
+      if (sid == 0)
+	pcspace = read_register (SR4_REGNUM);
+      else
+	pcspace = read_register (SR4_REGNUM + 4 + sid);
+      memcpy (inf_status->registers + REGISTER_BYTE (PCSQ_HEAD_REGNUM),
+	      &pcspace, 4);
+      memcpy (inf_status->registers + REGISTER_BYTE (PCSQ_TAIL_REGNUM),
+	      &pcspace, 4);
+    }
+  else
+    pcspace = read_register (PCSQ_HEAD_REGNUM);
+
+  /* Space for "arguments"; the RP goes in here. */
+  sp = read_register (SP_REGNUM) + 48;
+  int_buffer = read_register (RP_REGNUM) | 0x3;
+  write_memory (sp - 20, (char *)&int_buffer, 4);
+
+  int_buffer = TARGET_READ_FP ();
+  write_memory (sp, (char *)&int_buffer, 4);
+
+  write_register (FP_REGNUM, sp);
+
+  sp += 8;
+
+  for (regnum = 1; regnum < 32; regnum++)
+    if (regnum != RP_REGNUM && regnum != FP_REGNUM)
+      sp = push_word (sp, read_register (regnum));
+
+  sp += 4;
+
+  for (regnum = FP0_REGNUM; regnum < NUM_REGS; regnum++)
+    {
+      read_register_bytes (REGISTER_BYTE (regnum), (char *)&freg_buffer, 8);
+      sp = push_bytes (sp, (char *)&freg_buffer, 8);
+    }
+  sp = push_word (sp, read_register (IPSW_REGNUM));
+  sp = push_word (sp, read_register (SAR_REGNUM));
+  sp = push_word (sp, pc);
+  sp = push_word (sp, pcspace);
+  sp = push_word (sp, pc + 4);
+  sp = push_word (sp, pcspace);
+  write_register (SP_REGNUM, sp);
+}
+
+static void
+find_dummy_frame_regs (frame, frame_saved_regs)
+     struct frame_info *frame;
+     struct frame_saved_regs *frame_saved_regs;
+{
+  CORE_ADDR fp = frame->frame;
+  int i;
+
+  frame_saved_regs->regs[RP_REGNUM] = (fp - 20) & ~0x3;
+  frame_saved_regs->regs[FP_REGNUM] = fp;
+  frame_saved_regs->regs[1] = fp + 8;
+
+  for (fp += 12, i = 3; i < 32; i++)
+    {
+      if (i != FP_REGNUM)
+	{
+	  frame_saved_regs->regs[i] = fp;
+	  fp += 4;
+	}
+    }
+
+  fp += 4;
+  for (i = FP0_REGNUM; i < NUM_REGS; i++, fp += 8)
+    frame_saved_regs->regs[i] = fp;
+
+  frame_saved_regs->regs[IPSW_REGNUM] = fp;
+  frame_saved_regs->regs[SAR_REGNUM] = fp + 4;
+  frame_saved_regs->regs[PCOQ_HEAD_REGNUM] = fp + 8;
+  frame_saved_regs->regs[PCSQ_HEAD_REGNUM] = fp + 12;
+  frame_saved_regs->regs[PCOQ_TAIL_REGNUM] = fp + 16;
+  frame_saved_regs->regs[PCSQ_TAIL_REGNUM] = fp + 20;
+}
+
+void
+hppa_pop_frame ()
+{
+  register struct frame_info *frame = get_current_frame ();
+  register CORE_ADDR fp, npc, target_pc;
+  register int regnum;
+  struct frame_saved_regs fsr;
+  double freg_buffer;
+
+  fp = FRAME_FP (frame);
+  get_frame_saved_regs (frame, &fsr);
+
+#ifndef NO_PC_SPACE_QUEUE_RESTORE
+  if (fsr.regs[IPSW_REGNUM])    /* Restoring a call dummy frame */
+    restore_pc_queue (&fsr);
+#endif
+
+  for (regnum = 31; regnum > 0; regnum--)
+    if (fsr.regs[regnum])
+      write_register (regnum, read_memory_integer (fsr.regs[regnum], 4));
+
+  for (regnum = NUM_REGS - 1; regnum >= FP0_REGNUM ; regnum--)
+    if (fsr.regs[regnum])
+      {
+	read_memory (fsr.regs[regnum], (char *)&freg_buffer, 8);
+        write_register_bytes (REGISTER_BYTE (regnum), (char *)&freg_buffer, 8);
+      }
+
+  if (fsr.regs[IPSW_REGNUM])
+    write_register (IPSW_REGNUM,
+                    read_memory_integer (fsr.regs[IPSW_REGNUM], 4));
+
+  if (fsr.regs[SAR_REGNUM])
+    write_register (SAR_REGNUM,
+                    read_memory_integer (fsr.regs[SAR_REGNUM], 4));
+
+  /* If the PC was explicitly saved, then just restore it.  */
+  if (fsr.regs[PCOQ_TAIL_REGNUM])
+    {
+      npc = read_memory_integer (fsr.regs[PCOQ_TAIL_REGNUM], 4);
+      write_register (PCOQ_TAIL_REGNUM, npc);
+    }
+  /* Else use the value in %rp to set the new PC.  */
+  else 
+    {
+      npc = read_register (RP_REGNUM);
+      write_pc (npc);
+    }
+
+  write_register (FP_REGNUM, read_memory_integer (fp, 4));
+
+  if (fsr.regs[IPSW_REGNUM])    /* call dummy */
+    write_register (SP_REGNUM, fp - 48);
+  else
+    write_register (SP_REGNUM, fp);
+
+  /* The PC we just restored may be inside a return trampoline.  If so
+     we want to restart the inferior and run it through the trampoline.
+
+     Do this by setting a momentary breakpoint at the location the
+     trampoline returns to. 
+
+     Don't skip through the trampoline if we're popping a dummy frame.  */
+  target_pc = SKIP_TRAMPOLINE_CODE (npc & ~0x3) & ~0x3;
+  if (target_pc && !fsr.regs[IPSW_REGNUM])
+    {
+      struct symtab_and_line sal;
+      struct breakpoint *breakpoint;
+      struct cleanup *old_chain;
+
+      /* Set up our breakpoint.   Set it to be silent as the MI code
+	 for "return_command" will print the frame we returned to.  */
+      sal = find_pc_line (target_pc, 0);
+      sal.pc = target_pc;
+      breakpoint = set_momentary_breakpoint (sal, NULL, bp_finish);
+      breakpoint->silent = 1;
+
+      /* So we can clean things up.  */
+      old_chain = make_cleanup ((make_cleanup_func) delete_breakpoint, breakpoint);
+
+      /* Start up the inferior.  */
+      clear_proceed_status ();
+      proceed_to_finish = 1;
+      proceed ((CORE_ADDR) -1, TARGET_SIGNAL_DEFAULT, 0);
+
+      /* Perform our cleanups.  */
+      do_cleanups (old_chain);
+    }
+  flush_cached_frames ();
+}
+
+/* After returning to a dummy on the stack, restore the instruction
+   queue space registers. */
+
+static int
+restore_pc_queue (fsr)
+     struct frame_saved_regs *fsr;
+{
+  CORE_ADDR pc = read_pc ();
+  CORE_ADDR new_pc = read_memory_integer (fsr->regs[PCOQ_HEAD_REGNUM], 4);
+  struct target_waitstatus w;
+  int insn_count;
+
+  /* Advance past break instruction in the call dummy. */
+  write_register (PCOQ_HEAD_REGNUM, pc + 4);
+  write_register (PCOQ_TAIL_REGNUM, pc + 8);
+
+  /* HPUX doesn't let us set the space registers or the space
+     registers of the PC queue through ptrace. Boo, hiss.
+     Conveniently, the call dummy has this sequence of instructions
+     after the break:
+        mtsp r21, sr0
+        ble,n 0(sr0, r22)
+    
+     So, load up the registers and single step until we are in the
+     right place. */
+
+  write_register (21, read_memory_integer (fsr->regs[PCSQ_HEAD_REGNUM], 4));
+  write_register (22, new_pc);
+
+  for (insn_count = 0; insn_count < 3; insn_count++)
+    {
+      /* FIXME: What if the inferior gets a signal right now?  Want to
+	 merge this into wait_for_inferior (as a special kind of
+	 watchpoint?  By setting a breakpoint at the end?  Is there
+	 any other choice?  Is there *any* way to do this stuff with
+	 ptrace() or some equivalent?).  */
+      resume (1, 0);
+      target_wait (inferior_pid, &w);
+
+      if (w.kind == TARGET_WAITKIND_SIGNALLED)
+        {
+          stop_signal = w.value.sig;
+          terminal_ours_for_output ();
+          printf_unfiltered ("\nProgram terminated with signal %s, %s.\n",
+			     target_signal_to_name (stop_signal),
+			     target_signal_to_string (stop_signal));
+          gdb_flush (gdb_stdout);
+          return 0;
+        }
+    }
+  target_terminal_ours ();
+  target_fetch_registers (-1);
+  return 1;
+}
+
+#if 0
+CORE_ADDR
+hppa_push_arguments (nargs, args, sp, struct_return, struct_addr)
+     int nargs;
+     value_ptr *args;
+     CORE_ADDR sp;
+     int struct_return;
+     CORE_ADDR struct_addr;
+{
+  /* array of arguments' offsets */
+  int *offset = (int *)alloca(nargs * sizeof (int));
+  int cum = 0;
+  int i, alignment;
+  
+  for (i = 0; i < nargs; i++)
+    {
+      int x = 0;
+      /* cum is the sum of the lengths in bytes of
+	 the arguments seen so far */
+      cum += TYPE_LENGTH (VALUE_TYPE (args[i]));
+
+    /* value must go at proper alignment. Assume alignment is a
+	 power of two. */
+      alignment = hppa_alignof (VALUE_TYPE (args[i]));
+
+      if (cum % alignment)
+	cum = (cum + alignment) & -alignment;
+      offset[i] = -cum;
+
+    }
+  sp += max ((cum + 7) & -8, 16);
+
+  for (i = 0; i < nargs; i++)
+    write_memory (sp + offset[i], VALUE_CONTENTS (args[i]),
+		  TYPE_LENGTH (VALUE_TYPE (args[i])));
+
+  if (struct_return)
+    write_register (28, struct_addr);
+  return sp + 32;
+}
+#endif
+
+/* elz: I am rewriting this function, because the one above is a very 
+   obscure piece of code.
+   This function pushes the arguments on the stack. The stack grows up
+   on the PA. 
+   Each argument goes in one (or more) word (4 bytes) on the stack.
+   The first four words for the args must be allocated, even if they 
+   are not used. 
+   The 'topmost' arg is arg0, the 'bottom-most' is arg3. (if you think of 
+   them as 1 word long).
+   Below these there can be any number of arguments, as needed by the function.
+   If an arg is bigger than one word, it will be written on the stack 
+   occupying as many words as needed. Args that are bigger than 64bits
+   are not copied on the stack, a pointer is passed instead.
+
+   On top of the arg0 word there are other 8 words (32bytes) which are used
+   for other purposes */
+
+CORE_ADDR
+hppa_push_arguments (nargs, args, sp, struct_return, struct_addr)
+     int nargs;
+     value_ptr *args;
+     CORE_ADDR sp;
+     int struct_return;
+     CORE_ADDR struct_addr;
+{
+  /* array of arguments' offsets */
+  int *offset = (int *)alloca(nargs * sizeof (int));
+  /* array of arguments' lengths: real lengths in bytes, not aligned to word size */
+  int *lengths = (int *)alloca(nargs * sizeof (int));
+
+  int bytes_reserved; /* this is the number of bytes on the stack occupied by an
+                         argument. This will be always a multiple of 4 */
+
+  int cum_bytes_reserved = 0; /* this is the total number of bytes reserved by the args
+                                 seen so far. It is a multiple of 4 always */
+  int cum_bytes_aligned = 0; /* same as above, but aligned on 8 bytes */
+  int i; 
+
+  /* When an arg does not occupy a whole word, for instance in bitfields:
+     if the arg is x bits (0<x<32), it must be written
+     starting from the (x-1)-th position  down until the 0-th position. 
+     It is enough to align it to the word. */ 
+  /* if an arg occupies 8 bytes, it must be aligned on the 64-bits 
+     high order word in odd arg word. */
+  /* if an arg is larger than 64 bits, we need to pass a pointer to it, and
+     copy the actual value on the stack, so that the callee can play with it.
+     This is taken care of in valops.c in the call_function_by_hand function.
+     The argument that is received in this function here has already be converted
+     to a pointer to whatever is needed, so that it just can be pushed
+     as a word argument */
+  
+  for (i = 0; i < nargs; i++)
+    {
+
+      lengths[i] = TYPE_LENGTH (VALUE_TYPE (args[i]));
+
+      if (lengths[i] % 4)
+        bytes_reserved = (lengths[i] / 4) * 4 + 4;
+      else 
+        bytes_reserved = lengths[i];
+
+      offset[i] = cum_bytes_reserved + lengths[i];
+
+      if ((bytes_reserved == 8) && (offset[i] % 8)) /* if 64-bit arg is not 64 bit aligned */
+      {
+        int new_offset=0;
+        /* bytes_reserved is already aligned to the word, so we put it at one word
+           more down the stack. This will leave one empty word on the
+           stack, and one unused register. This is OK, see the calling
+           convention doc */
+        /* the offset may have to be moved to the corresponding position
+           one word down the stack, to maintain 
+           alignment. */
+        new_offset = (offset[i] / 8) * 8 + 8;
+        if ((new_offset - offset[i]) >=4) 
+        {
+         bytes_reserved += 4;
+         offset[i] += 4;
+        }
+      }
+
+      cum_bytes_reserved += bytes_reserved;
+
+    }
+
+  /* now move up the sp to reserve at least 4 words required for the args,
+     or more than this if needed */
+  /* wee also need to keep the sp aligned to 8 bytes */
+  cum_bytes_aligned = STACK_ALIGN (cum_bytes_reserved);
+  sp += max (cum_bytes_aligned, 16);
+
+  /* now write each of the args at the proper offset down the stack */
+  for (i = 0; i < nargs; i++)
+    write_memory (sp - offset[i], VALUE_CONTENTS (args[i]), lengths[i]);
+		  
+
+ /* if a structure has to be returned, set up register 28 to hold its address */
+  if (struct_return)
+    write_register (28, struct_addr);
+
+ /* the stack will have other 8 words on top of the args */
+  return sp + 32;
+}
+
+
+/* elz: this function returns a value which is built looking at the given address.
+   It is called from call_function_by_hand, in case we need to return a 
+   value which is larger than 64 bits, and it is stored in the stack rather than 
+   in the registers r28 and r29 or fr4.
+   This function does the same stuff as value_being_returned in values.c, but
+   gets the value from the stack rather than from the buffer where all the
+   registers were saved when the function called completed. */
+value_ptr
+hppa_value_returned_from_stack (valtype , addr)
+     register struct type *valtype;
+     CORE_ADDR addr;
+{
+  register value_ptr val;
+
+  val = allocate_value (valtype);
+  CHECK_TYPEDEF (valtype);
+  target_read_memory(addr, VALUE_CONTENTS_RAW (val), TYPE_LENGTH (valtype));
+
+  return val;
+}
+
+
+
+/* elz: Used to lookup a symbol in the shared libraries.
+ This function calls shl_findsym, indirectly through a
+ call to __d_shl_get. __d_shl_get is in end.c, which is always
+ linked in by the hp compilers/linkers. 
+ The call to shl_findsym cannot be made directly because it needs
+ to be active in target address space. 
+ inputs: - minimal symbol pointer for the function we want to look up
+         - address in target space of the descriptor for the library
+           where we want to look the symbol up.
+           This address is retrieved using the 
+           som_solib_get_solib_by_pc function (somsolib.c). 
+ output: - real address in the library of the function.          
+ note: the handle can be null, in which case shl_findsym will look for
+       the symbol in all the loaded shared libraries.
+ files to look at if you need reference on this stuff:
+ dld.c, dld_shl_findsym.c
+ end.c
+ man entry for shl_findsym */        
+
+CORE_ADDR
+find_stub_with_shl_get(function, handle) 
+  struct minimal_symbol *function;
+  CORE_ADDR handle;
+{
+ struct symbol *get_sym, *symbol2;
+ struct minimal_symbol *buff_minsym, *msymbol;
+ struct type *ftype;
+ value_ptr *args;
+ value_ptr funcval, val;
+
+ int x, namelen, err_value, tmp = -1;
+ CORE_ADDR endo_buff_addr, value_return_addr, errno_return_addr;
+ CORE_ADDR stub_addr;
+
+
+    args           = (value_ptr *) alloca (sizeof (value_ptr) * 8);  /* 6 for the arguments and one null one??? */
+    funcval        = find_function_in_inferior("__d_shl_get");
+    get_sym        = lookup_symbol("__d_shl_get", NULL, VAR_NAMESPACE, NULL, NULL);
+    buff_minsym    = lookup_minimal_symbol("__buffer", NULL, NULL);
+    msymbol        = lookup_minimal_symbol ("__shldp", NULL, NULL);
+    symbol2 = lookup_symbol("__shldp", NULL, VAR_NAMESPACE, NULL, NULL);
+    endo_buff_addr = SYMBOL_VALUE_ADDRESS (buff_minsym);
+    namelen        = strlen(SYMBOL_NAME(function));
+    value_return_addr = endo_buff_addr + namelen;
+    ftype          = check_typedef(SYMBOL_TYPE(get_sym));
+
+    /* do alignment */
+    if ((x=value_return_addr % 64) !=0)
+       value_return_addr = value_return_addr + 64 - x;
+
+    errno_return_addr = value_return_addr + 64;
+
+    
+    /* set up stuff needed by __d_shl_get in buffer in end.o */
+
+    target_write_memory(endo_buff_addr, SYMBOL_NAME(function), namelen);
+    
+    target_write_memory(value_return_addr, (char *) &tmp, 4);
+    
+    target_write_memory(errno_return_addr, (char *) &tmp, 4);
+
+    target_write_memory(SYMBOL_VALUE_ADDRESS(msymbol), 
+                        (char *)&handle, 4);
+    
+    /* now prepare the arguments for the call */
+
+    args[0] = value_from_longest (TYPE_FIELD_TYPE(ftype, 0), 12);
+    args[1] = value_from_longest (TYPE_FIELD_TYPE(ftype, 1), SYMBOL_VALUE_ADDRESS(msymbol));
+    args[2] = value_from_longest (TYPE_FIELD_TYPE(ftype, 2), endo_buff_addr);
+    args[3] = value_from_longest (TYPE_FIELD_TYPE(ftype, 3), TYPE_PROCEDURE);
+    args[4] = value_from_longest (TYPE_FIELD_TYPE(ftype, 4), value_return_addr);
+    args[5] = value_from_longest (TYPE_FIELD_TYPE(ftype, 5), errno_return_addr);
+
+    /* now call the function */
+
+    val = call_function_by_hand(funcval, 6, args);
+
+    /* now get the results */
+
+    target_read_memory(errno_return_addr, (char *) &err_value, sizeof(err_value));
+
+    target_read_memory(value_return_addr, (char *) &stub_addr, sizeof(stub_addr));
+    if (stub_addr <= 0)
+        error("call to __d_shl_get failed, error code is %d", err_value); /* purecov: deadcode */
+    
+    return(stub_addr);
+}
+
+/* Cover routine for find_stub_with_shl_get to pass to catch_errors */ 
+static CORE_ADDR
+cover_find_stub_with_shl_get (args)
+  args_for_find_stub * args;
+{
+  return find_stub_with_shl_get (args->msym, args->solib_handle);
+}
+
+
+/* Insert the specified number of args and function address
+   into a call sequence of the above form stored at DUMMYNAME.
+
+   On the hppa we need to call the stack dummy through $$dyncall.
+   Therefore our version of FIX_CALL_DUMMY takes an extra argument,
+   real_pc, which is the location where gdb should start up the
+   inferior to do the function call. */
+
+CORE_ADDR
+hppa_fix_call_dummy (dummy, pc, fun, nargs, args, type, gcc_p)
+     char *dummy;
+     CORE_ADDR pc;
+     CORE_ADDR fun;
+     int nargs;
+     value_ptr *args;
+     struct type *type;
+     int gcc_p;
+{
+  CORE_ADDR dyncall_addr;
+  struct minimal_symbol *msymbol;
+  struct minimal_symbol *trampoline;
+  int flags = read_register (FLAGS_REGNUM);
+  struct unwind_table_entry *u;
+  CORE_ADDR new_stub=0;
+  CORE_ADDR solib_handle=0;
+
+  trampoline = NULL;
+  msymbol = lookup_minimal_symbol ("$$dyncall", NULL, NULL);
+  if (msymbol == NULL)
+    error ("Can't find an address for $$dyncall trampoline"); /* purecov: deadcode */
+
+  dyncall_addr = SYMBOL_VALUE_ADDRESS (msymbol);
+
+  /* FUN could be a procedure label, in which case we have to get
+     its real address and the value of its GOT/DP.  */
+  if (fun & 0x2)
+    {
+      /* Get the GOT/DP value for the target function.  It's
+	 at *(fun+4).  Note the call dummy is *NOT* allowed to
+	 trash %r19 before calling the target function.  */
+      write_register (19, read_memory_integer ((fun & ~0x3) + 4, 4));
+
+      /* Now get the real address for the function we are calling, it's
+	 at *fun.  */
+      fun = (CORE_ADDR) read_memory_integer (fun & ~0x3, 4);
+    }
+  else
+    {
+
+#ifndef GDB_TARGET_IS_PA_ELF
+      /* FUN could be either an export stub, or the real address of a
+	 function in a shared library.  We must call an import stub
+	 rather than the export stub or real function for lazy binding
+	 to work correctly.  */
+
+      /* elz: let's see if fun is in a shared library */
+      solib_handle = som_solib_get_solib_by_pc(fun);
+
+      /* elz: for 10.30 and 11.00 the calls via __d_plt_call cannot be made
+	 via import stubs, only via plables, so this code here becomes useless.
+	 On 10.20, the plables mechanism works too, so we just ignore this import 
+	 stub stuff */
+#if 0
+      if (solib_handle)
+	{
+	  struct objfile *objfile;
+	  struct minimal_symbol *funsymbol, *stub_symbol;
+	  CORE_ADDR newfun = 0;
+
+	  funsymbol = lookup_minimal_symbol_by_pc (fun);
+	  if (!funsymbol)
+	    error ("Unable to find minimal symbol for target fucntion.\n");
+
+	  /* Search all the object files for an import symbol with the
+	     right name. */
+	  ALL_OBJFILES (objfile)
+	    {
+	      stub_symbol = lookup_minimal_symbol (SYMBOL_NAME (funsymbol),
+						   NULL, objfile);
+	      /* Found a symbol with the right name.  */
+	      if (stub_symbol)
+		{
+		  struct unwind_table_entry *u;
+		  /* It must be a shared library trampoline.  */
+		  if (MSYMBOL_TYPE (stub_symbol) != mst_solib_trampoline)
+		    continue;
+
+		  /* It must also be an import stub.  */
+		  u = find_unwind_entry (SYMBOL_VALUE (stub_symbol));
+		  if (!u || u->stub_unwind.stub_type != IMPORT)
+		    continue;
+
+		  /* OK.  Looks like the correct import stub.  */
+		  newfun = SYMBOL_VALUE (stub_symbol);
+		  fun = newfun;
+		}
+	    }
+	  if (newfun == 0)
+	    write_register (19, som_solib_get_got_by_pc (fun));
+	}
+#endif /* end of if 0 */
+#endif
+    }
+
+  /* If we are calling an import stub (eg calling into a dynamic library)
+     then have sr4export call the magic __d_plt_call routine which is linked
+     in from end.o.  (You can't use _sr4export to call the import stub as
+     the value in sp-24 will get fried and you end up returning to the
+     wrong location.  You can't call the import stub directly as the code
+     to bind the PLT entry to a function can't return to a stack address.)  */
+
+  /* elz:
+     There does not have to be an import stub to call a routine in a
+     different load module (note: a "load module" is an a.out or a shared
+     library).  If you call a routine indirectly, going through $$dyncall (or
+     $$dyncall_external), you won't go through an import stub.  Import stubs
+     are only used for direct calls to an imported routine.
+
+     What you (wdb) need is to go through $$dyncall with a proper plabel for
+     the imported routine.  shl_findsym() returns you the address of a plabel
+     suitable for use in making an indirect call through, e.g., through
+     $$dyncall.
+     This is taken care below with the call to find_stub_.... */
+#if 0
+  /* elz: this check here is not necessary if we are going to call stuff through
+     plabels only, we just now check whether the function we call is in a shlib */
+  u = find_unwind_entry (fun);
+
+  if (u && u->stub_unwind.stub_type == IMPORT || 
+      (!(u && u->stub_unwind.stub_type == IMPORT) && solib_handle))
+#endif /* 0 */
+  if (solib_handle)
+    {
+      CORE_ADDR new_fun;
+
+      /* Prefer __gcc_plt_call over the HP supplied routine because
+	 __gcc_plt_call works for any number of arguments.  */
+      trampoline = lookup_minimal_symbol ("__gcc_plt_call", NULL, NULL);
+      if (trampoline == NULL)
+	trampoline = lookup_minimal_symbol ("__d_plt_call", NULL, NULL);
+
+      if (trampoline == NULL)
+	{
+	  error ("Can't find an address for __d_plt_call or __gcc_plt_call trampoline\nSuggest linking executable with -g (links in /opt/langtools/lib/end.o)");
+	}
+      /* This is where sr4export will jump to.  */
+      new_fun = SYMBOL_VALUE_ADDRESS (trampoline);
+
+      if (strcmp (SYMBOL_NAME (trampoline), "__d_plt_call") == 0)
+	{
+          /* if the function is in a shared library, but we have no import sub for 
+             it, we need to get the plabel from a call to __d_shl_get, which is a 
+             function in end.o. To call this function we need to set up various things */
+	  
+	  /* actually now we just use the plabel any time we make the call,
+	     because on 10.30 and 11.00 this is the only acceptable way. This also
+	     works fine for 10.20 */
+	  /* if (!(u && u->stub_unwind.stub_type == IMPORT) && solib_handle) */
+            {
+              struct minimal_symbol *fmsymbol = lookup_minimal_symbol_by_pc(fun);
+              
+              new_stub = find_stub_with_shl_get(fmsymbol, solib_handle);
+
+              if (new_stub == NULL) 
+                error("Can't find an import stub for %s", SYMBOL_NAME(fmsymbol)); /* purecov: deadcode */
+            }
+
+	  /* We have to store the address of the stub in __shlib_funcptr.  */
+	    msymbol = lookup_minimal_symbol ("__shlib_funcptr", NULL,
+					     (struct objfile *)NULL);
+	    if (msymbol == NULL)
+	      error ("Can't find an address for __shlib_funcptr"); /* purecov: deadcode */
+
+         /* if (new_stub != NULL) */
+	     target_write_memory (SYMBOL_VALUE_ADDRESS (msymbol), (char *)&new_stub, 4);
+         /* this is no longer used */
+         /* else
+	     target_write_memory (SYMBOL_VALUE_ADDRESS (msymbol), (char *)&fun, 4); */
+
+	  /* We want sr4export to call __d_plt_call, so we claim it is
+	     the final target.  Clear trampoline.  */
+	    fun = new_fun;
+	    trampoline = NULL;
+	}
+    }
+
+  /* Store upper 21 bits of function address into ldil.  fun will either be
+     the final target (most cases) or __d_plt_call when calling into a shared
+     library and __gcc_plt_call is not available.  */
+  store_unsigned_integer
+    (&dummy[FUNC_LDIL_OFFSET],
+     INSTRUCTION_SIZE,
+     deposit_21 (fun >> 11,
+		 extract_unsigned_integer (&dummy[FUNC_LDIL_OFFSET],
+					   INSTRUCTION_SIZE)));
+
+  /* Store lower 11 bits of function address into ldo */
+  store_unsigned_integer
+    (&dummy[FUNC_LDO_OFFSET],
+     INSTRUCTION_SIZE,
+     deposit_14 (fun & MASK_11,
+		 extract_unsigned_integer (&dummy[FUNC_LDO_OFFSET],
+					   INSTRUCTION_SIZE)));
+#ifdef SR4EXPORT_LDIL_OFFSET
+
+  {
+    CORE_ADDR trampoline_addr;
+
+    /* We may still need sr4export's address too.  */
+
+    if (trampoline == NULL)
+      {
+	msymbol = lookup_minimal_symbol ("_sr4export", NULL, NULL);
+	if (msymbol == NULL)
+	  error ("Can't find an address for _sr4export trampoline"); /* purecov: deadcode */
+
+	trampoline_addr = SYMBOL_VALUE_ADDRESS (msymbol);
+      }
+    else
+      trampoline_addr = SYMBOL_VALUE_ADDRESS (trampoline);
+
+
+    /* Store upper 21 bits of trampoline's address into ldil */
+    store_unsigned_integer
+      (&dummy[SR4EXPORT_LDIL_OFFSET],
+       INSTRUCTION_SIZE,
+       deposit_21 (trampoline_addr >> 11,
+		   extract_unsigned_integer (&dummy[SR4EXPORT_LDIL_OFFSET],
+					     INSTRUCTION_SIZE)));
+
+    /* Store lower 11 bits of trampoline's address into ldo */
+    store_unsigned_integer
+      (&dummy[SR4EXPORT_LDO_OFFSET],
+       INSTRUCTION_SIZE,
+       deposit_14 (trampoline_addr & MASK_11,
+		   extract_unsigned_integer (&dummy[SR4EXPORT_LDO_OFFSET],
+					     INSTRUCTION_SIZE)));
+  }
+#endif
+
+  write_register (22, pc);
+
+  /* If we are in a syscall, then we should call the stack dummy
+     directly.  $$dyncall is not needed as the kernel sets up the
+     space id registers properly based on the value in %r31.  In
+     fact calling $$dyncall will not work because the value in %r22
+     will be clobbered on the syscall exit path. 
+
+     Similarly if the current PC is in a shared library.  Note however,
+     this scheme won't work if the shared library isn't mapped into
+     the same space as the stack.  */
+  if (flags & 2)
+    return pc;
+#ifndef GDB_TARGET_IS_PA_ELF
+  else if (som_solib_get_got_by_pc (target_read_pc (inferior_pid)))
+    return pc;
+#endif
+  else
+    return dyncall_addr;
+
+}
+
+
+
+
+/* If the pid is in a syscall, then the FP register is not readable.
+   We'll return zero in that case, rather than attempting to read it
+   and cause a warning. */
+CORE_ADDR
+target_read_fp (pid)
+  int  pid;
+{
+  int flags = read_register (FLAGS_REGNUM);
+
+  if (flags & 2) {
+    return (CORE_ADDR) 0;
+  }
+
+  /* This is the only site that may directly read_register () the FP
+     register.  All others must use TARGET_READ_FP (). */
+  return read_register (FP_REGNUM);
+}
+
+
+/* Get the PC from %r31 if currently in a syscall.  Also mask out privilege
+   bits.  */
+
+CORE_ADDR
+target_read_pc (pid)
+     int pid;
+{
+  int flags = read_register_pid (FLAGS_REGNUM, pid);
+
+  /* The following test does not belong here.  It is OS-specific, and belongs
+     in native code.  */
+  /* Test SS_INSYSCALL */
+  if (flags & 2)
+    return read_register_pid (31, pid) & ~0x3;
+
+  return read_register_pid (PC_REGNUM, pid) & ~0x3;
+}
+
+/* Write out the PC.  If currently in a syscall, then also write the new
+   PC value into %r31.  */
+
+void
+target_write_pc (v, pid)
+     CORE_ADDR v;
+     int pid;
+{
+  int flags = read_register_pid (FLAGS_REGNUM, pid);
+
+  /* The following test does not belong here.  It is OS-specific, and belongs
+     in native code.  */
+  /* If in a syscall, then set %r31.  Also make sure to get the 
+     privilege bits set correctly.  */
+  /* Test SS_INSYSCALL */
+  if (flags & 2)
+    write_register_pid (31, v | 0x3, pid);
+
+  write_register_pid (PC_REGNUM, v, pid);
+  write_register_pid (NPC_REGNUM, v + 4, pid);
+}
+
+/* return the alignment of a type in bytes. Structures have the maximum
+   alignment required by their fields. */
+
+static int
+hppa_alignof (type)
+     struct type *type;
+{
+  int max_align, align, i;
+  CHECK_TYPEDEF (type);
+  switch (TYPE_CODE (type))
+    {
+    case TYPE_CODE_PTR:
+    case TYPE_CODE_INT:
+    case TYPE_CODE_FLT:
+      return TYPE_LENGTH (type);
+    case TYPE_CODE_ARRAY:
+      return hppa_alignof (TYPE_FIELD_TYPE (type, 0));
+    case TYPE_CODE_STRUCT:
+    case TYPE_CODE_UNION:
+      max_align = 1;
+      for (i = 0; i < TYPE_NFIELDS (type); i++)
+	{
+	  /* Bit fields have no real alignment. */
+	  /* if (!TYPE_FIELD_BITPOS (type, i)) */
+	  if (!TYPE_FIELD_BITSIZE (type, i)) /* elz: this should be bitsize */
+	    {
+	      align = hppa_alignof (TYPE_FIELD_TYPE (type, i));
+	      max_align = max (max_align, align);
+	    }
+	}
+      return max_align;
+    default:
+      return 4;
+    }
+}
+
+/* Print the register regnum, or all registers if regnum is -1 */
+
+void
+pa_do_registers_info (regnum, fpregs)
+     int regnum;
+     int fpregs;
+{
+  char raw_regs [REGISTER_BYTES];
+  int i;
+
+  /* Make a copy of gdb's save area (may cause actual
+     reads from the target). */
+  for (i = 0; i < NUM_REGS; i++)
+    read_relative_register_raw_bytes (i, raw_regs + REGISTER_BYTE (i));
+
+  if (regnum == -1)
+    pa_print_registers (raw_regs, regnum, fpregs);
+  else if (regnum < FP4_REGNUM) {
+    long reg_val[2];
+      
+    /* Why is the value not passed through "extract_signed_integer"
+       as in "pa_print_registers" below? */
+    pa_register_look_aside(raw_regs, regnum, &reg_val[0]);
+
+    if(!is_pa_2) {
+      printf_unfiltered ("%s %x\n", REGISTER_NAME (regnum), reg_val[1]);
+    }
+    else {
+      /* Fancy % formats to prevent leading zeros. */
+      if(reg_val[0] == 0)
+	printf_unfiltered("%s %x\n", REGISTER_NAME (regnum), reg_val[1]);
+      else
+	printf_unfiltered("%s %x%8.8x\n", REGISTER_NAME (regnum),
+			   reg_val[0], reg_val[1]);        
+    }
+  }
+  else
+      /* Note that real floating point values only start at
+         FP4_REGNUM.  FP0 and up are just status and error
+         registers, which have integral (bit) values. */
+    pa_print_fp_reg (regnum);
+}
+
+/********** new function ********************/
+void
+pa_do_strcat_registers_info (regnum, fpregs, stream, precision)
+     int regnum;
+     int fpregs;
+     GDB_FILE *stream;
+     enum precision_type precision;
+{
+  char raw_regs [REGISTER_BYTES];
+  int i;
+
+  /* Make a copy of gdb's save area (may cause actual
+     reads from the target). */  
+  for (i = 0; i < NUM_REGS; i++)
+    read_relative_register_raw_bytes (i, raw_regs + REGISTER_BYTE (i));
+
+  if (regnum == -1)
+    pa_strcat_registers (raw_regs, regnum, fpregs, stream);
+
+  else if (regnum < FP4_REGNUM) {
+    long reg_val[2];
+      
+    /* Why is the value not passed through "extract_signed_integer"
+       as in "pa_print_registers" below? */
+    pa_register_look_aside(raw_regs, regnum, &reg_val[0]);
+
+    if(!is_pa_2) {
+      fprintf_unfiltered (stream, "%s %x", REGISTER_NAME (regnum), reg_val[1]);
+    }
+    else {
+      /* Fancy % formats to prevent leading zeros. */
+      if(reg_val[0] == 0)
+	fprintf_unfiltered(stream, "%s %x", REGISTER_NAME (regnum),
+			   reg_val[1]);
+      else
+	fprintf_unfiltered(stream, "%s %x%8.8x", REGISTER_NAME (regnum),
+			   reg_val[0], reg_val[1]);        
+    }
+  }
+  else
+      /* Note that real floating point values only start at
+         FP4_REGNUM.  FP0 and up are just status and error
+         registers, which have integral (bit) values. */
+    pa_strcat_fp_reg (regnum, stream, precision);
+}
+
+/* If this is a PA2.0 machine, fetch the real 64-bit register
+   value.  Otherwise use the info from gdb's saved register area.
+
+   Note that reg_val is really expected to be an array of longs,
+   with two elements. */
+static void
+pa_register_look_aside(raw_regs, regnum, raw_val)
+     char *raw_regs;
+     int   regnum;
+     long *raw_val;
+{
+  static int know_which = 0;  /* False */
+
+  int          regaddr;
+  unsigned int offset;
+  register int i;
+  int          start;
+  
+  
+  char buf[MAX_REGISTER_RAW_SIZE];
+  long long reg_val;
+
+  if(!know_which) {
+     if(CPU_PA_RISC2_0 == sysconf(_SC_CPU_VERSION)) {
+        is_pa_2 = (1==1);
+     }
+     
+     know_which = 1;  /* True */
+  }
+
+  raw_val[0] = 0;
+  raw_val[1] = 0;
+
+  if(!is_pa_2) {
+      raw_val[1] = *(long *)(raw_regs + REGISTER_BYTE(regnum));
+      return;
+  }
+
+  /* Code below copied from hppah-nat.c, with fixes for wide
+     registers, using different area of save_state, etc. */
+  if (regnum == FLAGS_REGNUM || regnum >= FP0_REGNUM ||
+      !HAVE_STRUCT_SAVE_STATE_T || !HAVE_STRUCT_MEMBER_SS_WIDE) {
+      /* Use narrow regs area of save_state and default macro. */
+      offset  = U_REGS_OFFSET;
+      regaddr = register_addr(regnum, offset);
+      start   = 1;
+  }
+  else {
+      /* Use wide regs area, and calculate registers as 8 bytes wide.
+
+         We'd like to do this, but current version of "C" doesn't
+         permit "offsetof":
+
+            offset  = offsetof(save_state_t, ss_wide);
+
+         Note that to avoid "C" doing typed pointer arithmetic, we
+         have to cast away the type in our offset calculation:
+         otherwise we get an offset of 1! */
+
+      /* #if the following code out so that this file can still be
+         compiled on older HPUX boxes (< 10.20) which don't have
+         this structure/structure member.  */
+#if HAVE_STRUCT_SAVE_STATE_T == 1 && HAVE_STRUCT_MEMBER_SS_WIDE == 1
+      save_state_t temp;
+
+      offset = ((int) &temp.ss_wide) - ((int) &temp);
+      regaddr = offset + regnum * 8;
+      start   = 0;
+#endif
+  }
+   
+  for(i = start; i < 2; i++)
+    {
+      errno = 0;
+      raw_val[i] = call_ptrace (PT_RUREGS, inferior_pid,
+  	 	                (PTRACE_ARG3_TYPE) regaddr, 0);
+      if (errno != 0)
+	{
+	  /* Warning, not error, in case we are attached; sometimes the
+	     kernel doesn't let us at the registers.  */
+	  char *err = safe_strerror (errno);
+	  char *msg = alloca (strlen (err) + 128);
+	  sprintf (msg, "reading register %s: %s", REGISTER_NAME (regnum), err);
+	  warning (msg);
+	  goto error_exit;
+	}
+
+      regaddr += sizeof (long);
+    }
+    
+  if (regnum == PCOQ_HEAD_REGNUM || regnum == PCOQ_TAIL_REGNUM)
+    raw_val[1] &= ~0x3; /* I think we're masking out space bits */
+
+error_exit:
+  ;
+}
+
+/* "Info all-reg" command */
+                                                    
+static void
+pa_print_registers (raw_regs, regnum, fpregs)
+     char *raw_regs;
+     int regnum;
+     int fpregs;
+{
+  int i,j;
+  long raw_val[2];   /* Alas, we are compiled so that "long long" is 32 bits */
+  long long_val;
+
+  for (i = 0; i < 18; i++)
+    {
+      for (j = 0; j < 4; j++)
+	{
+          /* Q: Why is the value passed through "extract_signed_integer",
+	        while above, in "pa_do_registers_info" it isn't?
+             A: ? */
+	  pa_register_look_aside(raw_regs, i+(j*18), &raw_val[0]);
+
+          /* Even fancier % formats to prevent leading zeros
+             and still maintain the output in columns. */
+          if(!is_pa_2) {
+              /* Being big-endian, on this machine the low bits
+                 (the ones we want to look at) are in the second longword. */
+   	      long_val = extract_signed_integer (&raw_val[1], 4);
+  	      printf_filtered ("%8.8s: %8x  ",
+			       REGISTER_NAME (i+(j*18)), long_val);
+	  }
+          else {
+   	      /* raw_val = extract_signed_integer(&raw_val, 8); */
+              if(raw_val[0] == 0)
+  	          printf_filtered("%8.8s:         %8x  ",
+				  REGISTER_NAME (i+(j*18)), raw_val[1]);
+              else
+  	          printf_filtered("%8.8s: %8x%8.8x  ", REGISTER_NAME (i+(j*18)),
+				  raw_val[0], raw_val[1]);
+          }
+	}
+      printf_unfiltered ("\n");
+    }
+  
+  if (fpregs)
+  for (i = FP4_REGNUM; i < NUM_REGS; i++)  /* FP4_REGNUM == 72 */
+      pa_print_fp_reg (i);
+}
+
+/************* new function ******************/                                                    
+static void
+pa_strcat_registers (raw_regs, regnum, fpregs, stream)
+     char *raw_regs;
+     int regnum;
+     int fpregs;
+     GDB_FILE *stream;
+{
+  int i,j;
+  long raw_val[2];   /* Alas, we are compiled so that "long long" is 32 bits */
+  long long_val;
+  enum precision_type precision;
+
+  precision = unspecified_precision;
+
+  for (i = 0; i < 18; i++)
+    {
+      for (j = 0; j < 4; j++)
+	{
+          /* Q: Why is the value passed through "extract_signed_integer",
+                while above, in "pa_do_registers_info" it isn't?
+             A: ? */
+	  pa_register_look_aside(raw_regs, i+(j*18), &raw_val[0]);
+
+          /* Even fancier % formats to prevent leading zeros
+             and still maintain the output in columns. */
+          if(!is_pa_2) {
+              /* Being big-endian, on this machine the low bits
+                 (the ones we want to look at) are in the second longword. */
+   	      long_val = extract_signed_integer(&raw_val[1], 4);
+  	      fprintf_filtered (stream, "%8.8s: %8x  ", REGISTER_NAME (i+(j*18)), long_val);
+	  }
+          else {
+   	      /* raw_val = extract_signed_integer(&raw_val, 8); */
+              if(raw_val[0] == 0)
+  	          fprintf_filtered(stream, "%8.8s:         %8x  ", REGISTER_NAME (i+(j*18)),
+                                   raw_val[1]);
+              else
+  	          fprintf_filtered(stream, "%8.8s: %8x%8.8x  ", REGISTER_NAME (i+(j*18)),
+                                    raw_val[0], raw_val[1]);
+          }
+	}
+      fprintf_unfiltered (stream, "\n");
+    }
+  
+  if (fpregs)
+  for (i = FP4_REGNUM; i < NUM_REGS; i++)  /* FP4_REGNUM == 72 */
+      pa_strcat_fp_reg (i, stream, precision);
+}
+
+static void
+pa_print_fp_reg (i)
+     int i;
+{
+  char raw_buffer[MAX_REGISTER_RAW_SIZE];
+  char virtual_buffer[MAX_REGISTER_VIRTUAL_SIZE];
+
+  /* Get 32bits of data.  */
+  read_relative_register_raw_bytes (i, raw_buffer);
+
+  /* Put it in the buffer.  No conversions are ever necessary.  */
+  memcpy (virtual_buffer, raw_buffer, REGISTER_RAW_SIZE (i));
+
+  fputs_filtered (REGISTER_NAME (i), gdb_stdout);
+  print_spaces_filtered (8 - strlen (REGISTER_NAME (i)), gdb_stdout);
+  fputs_filtered ("(single precision)     ", gdb_stdout);
+
+  val_print (REGISTER_VIRTUAL_TYPE (i), virtual_buffer, 0, 0, gdb_stdout, 0,
+	     1, 0, Val_pretty_default);
+  printf_filtered ("\n");
+
+  /* If "i" is even, then this register can also be a double-precision
+     FP register.  Dump it out as such.  */
+  if ((i % 2) == 0)
+    {
+      /* Get the data in raw format for the 2nd half.  */
+      read_relative_register_raw_bytes (i + 1, raw_buffer);
+
+      /* Copy it into the appropriate part of the virtual buffer.  */
+      memcpy (virtual_buffer + REGISTER_RAW_SIZE (i), raw_buffer,
+	      REGISTER_RAW_SIZE (i));
+
+      /* Dump it as a double.  */
+      fputs_filtered (REGISTER_NAME (i), gdb_stdout);
+      print_spaces_filtered (8 - strlen (REGISTER_NAME (i)), gdb_stdout);
+      fputs_filtered ("(double precision)     ", gdb_stdout);
+
+      val_print (builtin_type_double, virtual_buffer, 0, 0, gdb_stdout, 0,
+		 1, 0, Val_pretty_default);
+      printf_filtered ("\n");
+    }
+}
+
+/*************** new function ***********************/
+static void
+pa_strcat_fp_reg (i, stream, precision)
+     int i;
+     GDB_FILE *stream;
+     enum precision_type precision;
+{
+  char raw_buffer[MAX_REGISTER_RAW_SIZE];
+  char virtual_buffer[MAX_REGISTER_VIRTUAL_SIZE];
+
+  fputs_filtered (REGISTER_NAME (i), stream);
+  print_spaces_filtered (8 - strlen (REGISTER_NAME (i)), stream);
+
+  /* Get 32bits of data.  */
+  read_relative_register_raw_bytes (i, raw_buffer);
+
+  /* Put it in the buffer.  No conversions are ever necessary.  */
+  memcpy (virtual_buffer, raw_buffer, REGISTER_RAW_SIZE (i));
+
+  if (precision == double_precision && (i % 2) == 0)
+    {
+
+    char raw_buf[MAX_REGISTER_RAW_SIZE];
+ 
+    /* Get the data in raw format for the 2nd half.  */
+    read_relative_register_raw_bytes (i + 1, raw_buf);
+ 
+    /* Copy it into the appropriate part of the virtual buffer.  */
+    memcpy (virtual_buffer + REGISTER_RAW_SIZE(i), raw_buf, REGISTER_RAW_SIZE (i));
+
+    val_print (builtin_type_double, virtual_buffer, 0, 0 , stream, 0, 
+               1, 0, Val_pretty_default);
+
+    }
+  else { 
+    val_print (REGISTER_VIRTUAL_TYPE (i), virtual_buffer, 0, 0, stream, 0,
+	       1, 0, Val_pretty_default);
+  }
+
+}
+
+/* Return one if PC is in the call path of a trampoline, else return zero.
+
+   Note we return one for *any* call trampoline (long-call, arg-reloc), not
+   just shared library trampolines (import, export).  */
+
+int
+in_solib_call_trampoline (pc, name)
+     CORE_ADDR pc;
+     char *name;
+{
+  struct minimal_symbol *minsym;
+  struct unwind_table_entry *u;
+  static CORE_ADDR dyncall = 0;
+  static CORE_ADDR sr4export = 0;
+
+/* FIXME XXX - dyncall and sr4export must be initialized whenever we get a
+   new exec file */
+
+  /* First see if PC is in one of the two C-library trampolines.  */
+  if (!dyncall)
+    {
+      minsym = lookup_minimal_symbol ("$$dyncall", NULL, NULL);
+      if (minsym)
+	dyncall = SYMBOL_VALUE_ADDRESS (minsym);
+      else
+	dyncall = -1;
+    }
+
+  if (!sr4export)
+    {
+      minsym = lookup_minimal_symbol ("_sr4export", NULL, NULL);
+      if (minsym)
+	sr4export = SYMBOL_VALUE_ADDRESS (minsym);
+      else
+	sr4export = -1;
+    }
+
+  if (pc == dyncall || pc == sr4export)
+    return 1;
+
+  /* Get the unwind descriptor corresponding to PC, return zero
+     if no unwind was found.  */
+  u = find_unwind_entry (pc);
+  if (!u)
+    return 0;
+
+  /* If this isn't a linker stub, then return now.  */
+  if (u->stub_unwind.stub_type == 0)
+    return 0;
+
+  /* By definition a long-branch stub is a call stub.  */
+  if (u->stub_unwind.stub_type == LONG_BRANCH)
+    return 1;
+
+  /* The call and return path execute the same instructions within
+     an IMPORT stub!  So an IMPORT stub is both a call and return
+     trampoline.  */
+  if (u->stub_unwind.stub_type == IMPORT)
+    return 1;
+
+  /* Parameter relocation stubs always have a call path and may have a
+     return path.  */
+  if (u->stub_unwind.stub_type == PARAMETER_RELOCATION
+      || u->stub_unwind.stub_type == EXPORT)
+    {
+      CORE_ADDR addr;
+
+      /* Search forward from the current PC until we hit a branch
+	 or the end of the stub.  */
+      for (addr = pc; addr <= u->region_end; addr += 4)
+	{
+	  unsigned long insn;
+
+	  insn = read_memory_integer (addr, 4);
+
+	  /* Does it look like a bl?  If so then it's the call path, if
+	     we find a bv or be first, then we're on the return path.  */
+	  if ((insn & 0xfc00e000) == 0xe8000000)
+	    return 1;
+	  else if ((insn & 0xfc00e001) == 0xe800c000
+		   || (insn & 0xfc000000) == 0xe0000000)
+	    return 0;
+	}
+
+      /* Should never happen.  */
+      warning ("Unable to find branch in parameter relocation stub.\n"); /* purecov: deadcode */
+      return 0; /* purecov: deadcode */
+    }
+
+  /* Unknown stub type.  For now, just return zero.  */
+  return 0; /* purecov: deadcode */
+}
+
+/* Return one if PC is in the return path of a trampoline, else return zero.
+
+   Note we return one for *any* call trampoline (long-call, arg-reloc), not
+   just shared library trampolines (import, export).  */
+
+int
+in_solib_return_trampoline (pc, name)
+     CORE_ADDR pc;
+     char *name;
+{
+  struct unwind_table_entry *u;
+
+  /* Get the unwind descriptor corresponding to PC, return zero
+     if no unwind was found.  */
+  u = find_unwind_entry (pc);
+  if (!u)
+    return 0;
+
+  /* If this isn't a linker stub or it's just a long branch stub, then
+     return zero.  */
+  if (u->stub_unwind.stub_type == 0 || u->stub_unwind.stub_type == LONG_BRANCH)
+    return 0;
+
+  /* The call and return path execute the same instructions within
+     an IMPORT stub!  So an IMPORT stub is both a call and return
+     trampoline.  */
+  if (u->stub_unwind.stub_type == IMPORT)
+    return 1;
+
+  /* Parameter relocation stubs always have a call path and may have a
+     return path.  */
+  if (u->stub_unwind.stub_type == PARAMETER_RELOCATION
+      || u->stub_unwind.stub_type == EXPORT)
+    {
+      CORE_ADDR addr;
+
+      /* Search forward from the current PC until we hit a branch
+	 or the end of the stub.  */
+      for (addr = pc; addr <= u->region_end; addr += 4)
+	{
+	  unsigned long insn;
+
+	  insn = read_memory_integer (addr, 4);
+
+	  /* Does it look like a bl?  If so then it's the call path, if
+	     we find a bv or be first, then we're on the return path.  */
+	  if ((insn & 0xfc00e000) == 0xe8000000)
+	    return 0;
+	  else if ((insn & 0xfc00e001) == 0xe800c000
+		   || (insn & 0xfc000000) == 0xe0000000)
+	    return 1;
+	}
+
+      /* Should never happen.  */
+      warning ("Unable to find branch in parameter relocation stub.\n"); /* purecov: deadcode */
+      return 0; /* purecov: deadcode */
+    }
+
+  /* Unknown stub type.  For now, just return zero.  */
+  return 0; /* purecov: deadcode */
+
+}
+
+/* Figure out if PC is in a trampoline, and if so find out where
+   the trampoline will jump to.  If not in a trampoline, return zero.
+
+   Simple code examination probably is not a good idea since the code
+   sequences in trampolines can also appear in user code.
+
+   We use unwinds and information from the minimal symbol table to
+   determine when we're in a trampoline.  This won't work for ELF
+   (yet) since it doesn't create stub unwind entries.  Whether or
+   not ELF will create stub unwinds or normal unwinds for linker
+   stubs is still being debated.
+
+   This should handle simple calls through dyncall or sr4export,
+   long calls, argument relocation stubs, and dyncall/sr4export
+   calling an argument relocation stub.  It even handles some stubs
+   used in dynamic executables.  */
+
+# if 0
+CORE_ADDR
+skip_trampoline_code (pc, name)
+     CORE_ADDR pc;
+     char *name;
+{
+  return find_solib_trampoline_target(pc);
+}
+
+#endif
+
+CORE_ADDR
+skip_trampoline_code (pc, name)
+     CORE_ADDR pc;
+     char *name;
+{
+  long orig_pc = pc;
+  long prev_inst, curr_inst, loc;
+  static CORE_ADDR dyncall = 0;
+  static CORE_ADDR dyncall_external = 0;
+  static CORE_ADDR sr4export = 0;
+  struct minimal_symbol *msym;
+  struct unwind_table_entry *u;
+
+
+/* FIXME XXX - dyncall and sr4export must be initialized whenever we get a
+   new exec file */
+
+  if (!dyncall)
+    {
+      msym = lookup_minimal_symbol ("$$dyncall", NULL, NULL);
+      if (msym)
+	dyncall = SYMBOL_VALUE_ADDRESS (msym);
+      else
+	dyncall = -1;
+    }
+
+  if (!dyncall_external)
+    {
+      msym = lookup_minimal_symbol ("$$dyncall_external", NULL, NULL);
+      if (msym)
+	dyncall_external = SYMBOL_VALUE_ADDRESS (msym);
+      else
+	dyncall_external = -1;
+    }
+
+  if (!sr4export)
+    {
+      msym = lookup_minimal_symbol ("_sr4export", NULL, NULL);
+      if (msym)
+	sr4export = SYMBOL_VALUE_ADDRESS (msym);
+      else
+	sr4export = -1;
+    }
+
+  /* Addresses passed to dyncall may *NOT* be the actual address
+     of the function.  So we may have to do something special.  */
+  if (pc == dyncall)
+    {
+      pc = (CORE_ADDR) read_register (22);
+
+      /* If bit 30 (counting from the left) is on, then pc is the address of
+	 the PLT entry for this function, not the address of the function
+	 itself.  Bit 31 has meaning too, but only for MPE.  */
+      if (pc & 0x2)
+	pc = (CORE_ADDR) read_memory_integer (pc & ~0x3, 4);
+    }
+  if (pc == dyncall_external)
+    {
+      pc = (CORE_ADDR) read_register (22);
+      pc = (CORE_ADDR) read_memory_integer (pc & ~0x3, 4);
+    }
+  else if (pc == sr4export)
+    pc = (CORE_ADDR) (read_register (22));
+
+  /* Get the unwind descriptor corresponding to PC, return zero
+     if no unwind was found.  */
+  u = find_unwind_entry (pc);
+  if (!u)
+    return 0;
+
+  /* If this isn't a linker stub, then return now.  */
+  /* elz: attention here! (FIXME) because of a compiler/linker 
+     error, some stubs which should have a non zero stub_unwind.stub_type 
+     have unfortunately a value of zero. So this function would return here
+     as if we were not in a trampoline. To fix this, we go look at the partial
+     symbol information, which reports this guy as a stub.
+     (FIXME): Unfortunately, we are not that lucky: it turns out that the 
+     partial symbol information is also wrong sometimes. This is because 
+     when it is entered (somread.c::som_symtab_read()) it can happen that
+     if the type of the symbol (from the som) is Entry, and the symbol is
+     in a shared library, then it can also be a trampoline.  This would
+     be OK, except that I believe the way they decide if we are ina shared library
+     does not work. SOOOO..., even if we have a regular function w/o trampolines
+     its minimal symbol can be assigned type mst_solib_trampoline.
+     Also, if we find that the symbol is a real stub, then we fix the unwind
+     descriptor, and define the stub type to be EXPORT.
+     Hopefully this is correct most of the times. */ 
+  if (u->stub_unwind.stub_type == 0)
+  {
+
+/* elz: NOTE (FIXME!) once the problem with the unwind information is fixed
+   we can delete all the code which appears between the lines */
+/*--------------------------------------------------------------------------*/
+    msym = lookup_minimal_symbol_by_pc (pc);
+
+    if (msym == NULL || MSYMBOL_TYPE (msym) != mst_solib_trampoline)
+      return orig_pc == pc ? 0 : pc & ~0x3;
+
+    else if (msym != NULL && MSYMBOL_TYPE (msym) == mst_solib_trampoline)
+         {
+          struct objfile *objfile;
+          struct minimal_symbol *msymbol;
+          int function_found = 0;
+
+             /* go look if there is another minimal symbol with the same name as 
+                this one, but with type mst_text. This would happen if the msym
+                is an actual trampoline, in which case there would be another
+                symbol with the same name corresponding to the real function */
+
+             ALL_MSYMBOLS (objfile, msymbol)
+             {
+               if (MSYMBOL_TYPE (msymbol) == mst_text
+                    && STREQ (SYMBOL_NAME (msymbol) , SYMBOL_NAME (msym)))
+                 {
+                  function_found = 1;
+                  break;
+                 }
+             }
+
+            if (function_found)  
+                   /* the type of msym is correct (mst_solib_trampoline), but
+                      the unwind info is wrong, so set it to the correct value */
+                u->stub_unwind.stub_type = EXPORT;
+            else
+                   /* the stub type info in the unwind is correct (this is not a
+                      trampoline), but the msym type information is wrong, it
+                      should be mst_text. So we need to fix the msym, and also
+                      get out of this function */
+              {
+                  MSYMBOL_TYPE (msym) = mst_text;
+                  return orig_pc == pc ? 0 : pc & ~0x3;
+              }
+         }
+               
+/*--------------------------------------------------------------------------*/
+  }
+
+  /* It's a stub.  Search for a branch and figure out where it goes.
+     Note we have to handle multi insn branch sequences like ldil;ble.
+     Most (all?) other branches can be determined by examining the contents
+     of certain registers and the stack.  */
+
+  loc = pc;
+  curr_inst = 0;
+  prev_inst = 0;
+  while (1)
+    {
+      /* Make sure we haven't walked outside the range of this stub.  */
+      if (u != find_unwind_entry (loc))
+	{
+	  warning ("Unable to find branch in linker stub");
+	  return orig_pc == pc ? 0 : pc & ~0x3;
+	}
+
+      prev_inst = curr_inst;
+      curr_inst = read_memory_integer (loc, 4);
+
+      /* Does it look like a branch external using %r1?  Then it's the
+	 branch from the stub to the actual function.  */
+      if ((curr_inst & 0xffe0e000) == 0xe0202000)
+	{
+	  /* Yup.  See if the previous instruction loaded
+	     a value into %r1.  If so compute and return the jump address.  */
+	  if ((prev_inst & 0xffe00000) == 0x20200000)
+	    return (extract_21 (prev_inst) + extract_17 (curr_inst)) & ~0x3;
+	  else
+	    {
+	      warning ("Unable to find ldil X,%%r1 before ble Y(%%sr4,%%r1).");
+	      return orig_pc == pc ? 0 : pc & ~0x3;
+	    }
+	}
+
+      /* Does it look like a be 0(sr0,%r21)? OR 
+         Does it look like a be, n 0(sr0,%r21)? OR 
+         Does it look like a bve (r21)? (this is on PA2.0)
+         Does it look like a bve, n(r21)? (this is also on PA2.0)
+         That's the branch from an
+	 import stub to an export stub.
+
+	 It is impossible to determine the target of the branch via
+	 simple examination of instructions and/or data (consider
+	 that the address in the plabel may be the address of the
+	 bind-on-reference routine in the dynamic loader).
+
+	 So we have try an alternative approach.
+
+	 Get the name of the symbol at our current location; it should
+	 be a stub symbol with the same name as the symbol in the
+	 shared library.
+
+	 Then lookup a minimal symbol with the same name; we should
+	 get the minimal symbol for the target routine in the shared
+	 library as those take precedence of import/export stubs.  */
+      if ((curr_inst == 0xe2a00000) ||
+          (curr_inst == 0xe2a00002) ||
+          (curr_inst == 0xeaa0d000) ||
+          (curr_inst == 0xeaa0d002))
+	{
+	  struct minimal_symbol *stubsym, *libsym;
+
+	  stubsym = lookup_minimal_symbol_by_pc (loc);
+	  if (stubsym == NULL)
+	    {
+	      warning ("Unable to find symbol for 0x%x", loc);
+	      return orig_pc == pc ? 0 : pc & ~0x3;
+	    }
+
+	  libsym = lookup_minimal_symbol (SYMBOL_NAME (stubsym), NULL, NULL);
+	  if (libsym == NULL)
+	    {
+	      warning ("Unable to find library symbol for %s\n",
+		       SYMBOL_NAME (stubsym));
+	      return orig_pc == pc ? 0 : pc & ~0x3;
+	    }
+
+	  return SYMBOL_VALUE (libsym);
+	}
+
+      /* Does it look like bl X,%rp or bl X,%r0?  Another way to do a
+	 branch from the stub to the actual function.  */
+      /*elz*/
+      else if ((curr_inst & 0xffe0e000) == 0xe8400000
+	       || (curr_inst & 0xffe0e000) == 0xe8000000
+               || (curr_inst & 0xffe0e000) == 0xe800A000)
+	return (loc + extract_17 (curr_inst) + 8) & ~0x3;
+
+      /* Does it look like bv (rp)?   Note this depends on the
+	 current stack pointer being the same as the stack
+	 pointer in the stub itself!  This is a branch on from the
+	 stub back to the original caller.  */
+      /*else if ((curr_inst & 0xffe0e000) == 0xe840c000)*/
+      else if ((curr_inst & 0xffe0f000) == 0xe840c000)
+	{
+	  /* Yup.  See if the previous instruction loaded
+	     rp from sp - 8.  */
+	  if (prev_inst == 0x4bc23ff1)
+	    return (read_memory_integer
+		    (read_register (SP_REGNUM) - 8, 4)) & ~0x3;
+	  else
+	    {
+	      warning ("Unable to find restore of %%rp before bv (%%rp).");
+	      return orig_pc == pc ? 0 : pc & ~0x3;
+	    }
+	}
+
+      /* elz: added this case to capture the new instruction
+         at the end of the return part of an export stub used by
+         the PA2.0: BVE, n (rp) */
+      else if ((curr_inst & 0xffe0f000) == 0xe840d000)
+	{
+	  return (read_memory_integer 
+		  (read_register (SP_REGNUM) - 24, 4)) & ~0x3;
+	}
+
+      /* What about be,n 0(sr0,%rp)?  It's just another way we return to
+	 the original caller from the stub.  Used in dynamic executables.  */
+      else if (curr_inst == 0xe0400002)
+	{
+	  /* The value we jump to is sitting in sp - 24.  But that's
+	     loaded several instructions before the be instruction.
+	     I guess we could check for the previous instruction being
+	     mtsp %r1,%sr0 if we want to do sanity checking.  */
+	  return (read_memory_integer 
+		  (read_register (SP_REGNUM) - 24, 4)) & ~0x3;
+	}
+
+      /* Haven't found the branch yet, but we're still in the stub.
+	 Keep looking.  */
+      loc += 4;
+    }
+}
+
+
+/* For the given instruction (INST), return any adjustment it makes
+   to the stack pointer or zero for no adjustment. 
+
+   This only handles instructions commonly found in prologues.  */
+
+static int
+prologue_inst_adjust_sp (inst)
+     unsigned long inst;
+{
+  /* This must persist across calls.  */
+  static int save_high21;
+
+  /* The most common way to perform a stack adjustment ldo X(sp),sp */
+  if ((inst & 0xffffc000) == 0x37de0000)
+    return extract_14 (inst);
+
+  /* stwm X,D(sp) */
+  if ((inst & 0xffe00000) == 0x6fc00000)
+    return extract_14 (inst);
+
+  /* addil high21,%r1; ldo low11,(%r1),%r30)
+     save high bits in save_high21 for later use.  */
+  if ((inst & 0xffe00000) == 0x28200000)
+    {
+      save_high21 = extract_21 (inst);
+      return 0;
+    }
+
+  if ((inst & 0xffff0000) == 0x343e0000)
+    return save_high21 + extract_14 (inst);
+
+  /* fstws as used by the HP compilers.  */
+  if ((inst & 0xffffffe0) == 0x2fd01220)
+    return extract_5_load (inst);
+
+  /* No adjustment.  */
+  return 0;
+}
+
+/* Return nonzero if INST is a branch of some kind, else return zero.  */
+
+static int
+is_branch (inst)
+     unsigned long inst;
+{
+  switch (inst >> 26)
+    {
+    case 0x20:
+    case 0x21:
+    case 0x22:
+    case 0x23:
+    case 0x28:
+    case 0x29:
+    case 0x2a:
+    case 0x2b:
+    case 0x30:
+    case 0x31:
+    case 0x32:
+    case 0x33:
+    case 0x38:
+    case 0x39:
+    case 0x3a:
+      return 1;
+
+    default:
+      return 0;
+    }
+}
+
+/* Return the register number for a GR which is saved by INST or
+   zero it INST does not save a GR.  */
+
+static int
+inst_saves_gr (inst)
+     unsigned long inst;
+{
+  /* Does it look like a stw?  */
+  if ((inst >> 26) == 0x1a)
+    return extract_5R_store (inst);
+
+  /* Does it look like a stwm?  GCC & HPC may use this in prologues. */
+  if ((inst >> 26) == 0x1b)
+    return extract_5R_store (inst);
+
+  /* Does it look like sth or stb?  HPC versions 9.0 and later use these
+     too.  */
+  if ((inst >> 26) == 0x19 || (inst >> 26) == 0x18)
+    return extract_5R_store (inst);
+      
+  return 0;
+}
+
+/* Return the register number for a FR which is saved by INST or
+   zero it INST does not save a FR.
+
+   Note we only care about full 64bit register stores (that's the only
+   kind of stores the prologue will use).
+
+   FIXME: What about argument stores with the HP compiler in ANSI mode? */
+
+static int
+inst_saves_fr (inst)
+     unsigned long inst;
+{
+  /* is this an FSTDS ?*/
+  if ((inst & 0xfc00dfc0) == 0x2c001200)
+    return extract_5r_store (inst);
+  /* is this an FSTWS ?*/
+  if ((inst & 0xfc00df80) == 0x24001200)
+    return extract_5r_store (inst);
+  return 0;
+}
+
+/* Advance PC across any function entry prologue instructions
+   to reach some "real" code. 
+
+   Use information in the unwind table to determine what exactly should
+   be in the prologue.  */
+
+
+CORE_ADDR
+skip_prologue_hard_way (pc)
+     CORE_ADDR pc;
+{
+  char buf[4];
+  CORE_ADDR orig_pc = pc;
+  unsigned long inst, stack_remaining, save_gr, save_fr, save_rp, save_sp;
+  unsigned long args_stored, status, i, restart_gr, restart_fr;
+  struct unwind_table_entry *u;
+
+  restart_gr = 0;
+  restart_fr = 0;
+
+restart:
+  u = find_unwind_entry (pc);
+  if (!u)
+    return pc;
+
+  /* If we are not at the beginning of a function, then return now. */ 
+  if ((pc & ~0x3) != u->region_start)
+    return pc;
+
+  /* This is how much of a frame adjustment we need to account for.  */
+  stack_remaining = u->Total_frame_size << 3;
+
+  /* Magic register saves we want to know about.  */
+  save_rp = u->Save_RP;
+  save_sp = u->Save_SP;
+
+  /* An indication that args may be stored into the stack.  Unfortunately
+     the HPUX compilers tend to set this in cases where no args were
+     stored too!.  */
+  args_stored = 1;
+
+  /* Turn the Entry_GR field into a bitmask.  */
+  save_gr = 0;
+  for (i = 3; i < u->Entry_GR + 3; i++)
+    {
+      /* Frame pointer gets saved into a special location.  */
+      if (u->Save_SP && i == FP_REGNUM)
+	continue;
+
+      save_gr |= (1 << i);
+    }
+  save_gr &= ~restart_gr;
+
+  /* Turn the Entry_FR field into a bitmask too.  */
+  save_fr = 0;
+  for (i = 12; i < u->Entry_FR + 12; i++)
+    save_fr |= (1 << i);
+  save_fr &= ~restart_fr;
+
+  /* Loop until we find everything of interest or hit a branch.
+
+     For unoptimized GCC code and for any HP CC code this will never ever
+     examine any user instructions.
+
+     For optimzied GCC code we're faced with problems.  GCC will schedule
+     its prologue and make prologue instructions available for delay slot
+     filling.  The end result is user code gets mixed in with the prologue
+     and a prologue instruction may be in the delay slot of the first branch
+     or call.
+
+     Some unexpected things are expected with debugging optimized code, so
+     we allow this routine to walk past user instructions in optimized
+     GCC code.  */
+  while (save_gr || save_fr || save_rp || save_sp || stack_remaining > 0
+	 || args_stored)
+    {
+      unsigned int reg_num;
+      unsigned long old_stack_remaining, old_save_gr, old_save_fr;
+      unsigned long old_save_rp, old_save_sp, next_inst;
+
+      /* Save copies of all the triggers so we can compare them later
+	 (only for HPC).  */
+      old_save_gr = save_gr;
+      old_save_fr = save_fr;
+      old_save_rp = save_rp;
+      old_save_sp = save_sp;
+      old_stack_remaining = stack_remaining;
+
+      status = target_read_memory (pc, buf, 4);
+      inst = extract_unsigned_integer (buf, 4);
+       
+      /* Yow! */
+      if (status != 0)
+	return pc;
+
+      /* Note the interesting effects of this instruction.  */
+      stack_remaining -= prologue_inst_adjust_sp (inst);
+
+      /* There is only one instruction used for saving RP into the stack.  */
+      if (inst == 0x6bc23fd9)
+	save_rp = 0;
+
+      /* This is the only way we save SP into the stack.  At this time
+	 the HP compilers never bother to save SP into the stack.  */
+      if ((inst & 0xffffc000) == 0x6fc10000)
+	save_sp = 0;
+
+      /* Account for general and floating-point register saves.  */
+      reg_num = inst_saves_gr (inst);
+      save_gr &= ~(1 << reg_num);
+
+      /* Ugh.  Also account for argument stores into the stack.
+	 Unfortunately args_stored only tells us that some arguments
+	 where stored into the stack.  Not how many or what kind!
+
+	 This is a kludge as on the HP compiler sets this bit and it
+	 never does prologue scheduling.  So once we see one, skip past
+	 all of them.   We have similar code for the fp arg stores below.
+
+	 FIXME.  Can still die if we have a mix of GR and FR argument
+	 stores!  */
+      if (reg_num >= 23 && reg_num <= 26)
+	{
+	  while (reg_num >= 23 && reg_num <= 26)
+	    {
+	      pc += 4;
+	      status = target_read_memory (pc, buf, 4);
+	      inst = extract_unsigned_integer (buf, 4);
+	      if (status != 0)
+		return pc;
+	      reg_num = inst_saves_gr (inst);
+	    }
+	  args_stored = 0;
+	  continue;
+	}
+
+      reg_num = inst_saves_fr (inst);
+      save_fr &= ~(1 << reg_num);
+
+      status = target_read_memory (pc + 4, buf, 4);
+      next_inst = extract_unsigned_integer (buf, 4);
+       
+      /* Yow! */
+      if (status != 0)
+	return pc;
+
+      /* We've got to be read to handle the ldo before the fp register
+	 save.  */
+      if ((inst & 0xfc000000) == 0x34000000
+	  && inst_saves_fr (next_inst) >= 4
+	  && inst_saves_fr (next_inst) <= 7)
+	{
+	  /* So we drop into the code below in a reasonable state.  */
+	  reg_num = inst_saves_fr (next_inst);
+	  pc -= 4;
+	}
+
+      /* Ugh.  Also account for argument stores into the stack.
+	 This is a kludge as on the HP compiler sets this bit and it
+	 never does prologue scheduling.  So once we see one, skip past
+	 all of them.  */
+      if (reg_num >= 4 && reg_num <= 7)
+	{
+	  while (reg_num >= 4 && reg_num <= 7)
+	    {
+	      pc += 8;
+	      status = target_read_memory (pc, buf, 4);
+	      inst = extract_unsigned_integer (buf, 4);
+	      if (status != 0)
+		return pc;
+	      if ((inst & 0xfc000000) != 0x34000000)
+		break;
+	      status = target_read_memory (pc + 4, buf, 4);
+	      next_inst = extract_unsigned_integer (buf, 4);
+	      if (status != 0)
+		return pc;
+	      reg_num = inst_saves_fr (next_inst);
+	    }
+	  args_stored = 0;
+	  continue;
+	}
+
+      /* Quit if we hit any kind of branch.  This can happen if a prologue
+	 instruction is in the delay slot of the first call/branch.  */
+      if (is_branch (inst))
+	break;
+
+      /* What a crock.  The HP compilers set args_stored even if no
+	 arguments were stored into the stack (boo hiss).  This could
+	 cause this code to then skip a bunch of user insns (up to the
+	 first branch).
+
+	 To combat this we try to identify when args_stored was bogusly
+	 set and clear it.   We only do this when args_stored is nonzero,
+	 all other resources are accounted for, and nothing changed on
+	 this pass.  */
+      if (args_stored
+	  && ! (save_gr || save_fr || save_rp || save_sp || stack_remaining > 0)
+	  && old_save_gr == save_gr && old_save_fr == save_fr
+	  && old_save_rp == save_rp && old_save_sp == save_sp
+	  && old_stack_remaining == stack_remaining)
+	break;
+      
+      /* Bump the PC.  */
+      pc += 4;
+    }
+
+  /* We've got a tenative location for the end of the prologue.  However
+     because of limitations in the unwind descriptor mechanism we may
+     have went too far into user code looking for the save of a register
+     that does not exist.  So, if there registers we expected to be saved
+     but never were, mask them out and restart.
+
+     This should only happen in optimized code, and should be very rare.  */
+  if (save_gr || (save_fr && ! (restart_fr || restart_gr)))
+    {
+      pc = orig_pc;
+      restart_gr = save_gr;
+      restart_fr = save_fr;
+      goto restart;
+    }
+
+  return pc;
+}
+
+
+
+
+
+/* return 0 if we cannot determine the end of the prologue,
+   return the new pc value if we know where the prologue ends */
+
+static CORE_ADDR
+after_prologue (pc)
+     CORE_ADDR pc;
+{
+  struct symtab_and_line sal;
+  CORE_ADDR func_addr, func_end;
+  struct symbol *f;
+
+  if (!find_pc_partial_function (pc, NULL, &func_addr, &func_end))
+    return 0;                   /* Unknown */
+
+  f = find_pc_function (pc);
+  if (!f)
+    return 0;			/* no debug info, do it the hard way! */
+
+  sal = find_pc_line (func_addr, 0);
+
+  if (sal.end < func_end)
+  {
+  /* this happens when the function has no prologue, because the way 
+     find_pc_line works: elz. Note: this may not be a very good
+     way to decide whether a function has a prologue or not, but
+     it is the best I can do with the info available
+     Also, this will work for functions like: int f()
+                                              {
+                                               return 2;
+                                              }
+    I.e. the bp will be inserted at the first open brace.
+    For functions where the body is only one line written like this:
+                                             int f()
+                                             { return 2; }
+   this will make the breakpoint to be at the last brace, after the body
+   has been executed already. What's the point of stepping through a function
+   without any variables anyway??  */
+
+    if ((SYMBOL_LINE(f) > 0) && (SYMBOL_LINE(f) < sal.line))
+     return pc; /*no adjusment will be made*/
+    else
+     return sal.end; /* this is the end of the prologue */
+  }
+  /* The line after the prologue is after the end of the function.  In this
+     case, put the end of the prologue is the beginning of the function.  */
+  /* This should happen only when the function is prologueless and has no
+     code in it. For instance void dumb(){} Note: this kind of function
+     is  used quite a lot in the test system */
+
+  else return pc; /* no adjustment will be made */
+}
+
+/* To skip prologues, I use this predicate.  Returns either PC itself
+   if the code at PC does not look like a function prologue; otherwise
+   returns an address that (if we're lucky) follows the prologue.  If
+   LENIENT, then we must skip everything which is involved in setting
+   up the frame (it's OK to skip more, just so long as we don't skip
+   anything which might clobber the registers which are being saved.
+   Currently we must not skip more on the alpha, but we might the lenient
+   stuff some day.  */
+
+CORE_ADDR
+skip_prologue (pc)
+     CORE_ADDR pc;
+{
+    unsigned long inst;
+    int offset;
+    CORE_ADDR post_prologue_pc;
+    char buf[4];
+
+#ifdef GDB_TARGET_HAS_SHARED_LIBS
+    /* Silently return the unaltered pc upon memory errors.
+       This could happen on OSF/1 if decode_line_1 tries to skip the
+       prologue for quickstarted shared library functions when the
+       shared library is not yet mapped in.
+       Reading target memory is slow over serial lines, so we perform
+       this check only if the target has shared libraries.  */
+    if (target_read_memory (pc, buf, 4))
+      return pc;
+#endif
+
+    /* See if we can determine the end of the prologue via the symbol table.
+       If so, then return either PC, or the PC after the prologue, whichever
+       is greater.  */
+
+    post_prologue_pc = after_prologue (pc);
+
+    if (post_prologue_pc != 0)
+      return max (pc, post_prologue_pc);
+
+
+   /* Can't determine prologue from the symbol table, (this can happen if there
+      is no debug information)  so we need to fall back on the old code, which
+      looks at the instructions */
+  /* FIXME (elz) !!!!: this may create a problem if, once the bp is hit, the user says
+     where: the backtrace info is not right: this is because the point at which we
+     break is at the very first instruction of the function. At this time the stuff that
+     needs to be saved on the stack, has not been saved yet, so the backtrace
+     cannot know all it needs to know. This will need to be fixed in the
+     actual backtrace code. (Note: this is what DDE does) */
+
+    else 
+
+      return (skip_prologue_hard_way(pc));
+
+#if 0
+/* elz: I am keeping this code around just in case, but remember, all the
+   instructions are for alpha: you should change all to the hppa instructions */
+
+    /* Can't determine prologue from the symbol table, need to examine
+       instructions.  */
+
+    /* Skip the typical prologue instructions. These are the stack adjustment
+       instruction and the instructions that save registers on the stack
+       or in the gcc frame.  */
+    for (offset = 0; offset < 100; offset += 4)
+      {
+        int status;
+
+        status = read_memory_nobpt (pc + offset, buf, 4);
+        if (status)
+          memory_error (status, pc + offset);
+        inst = extract_unsigned_integer (buf, 4);
+
+        /* The alpha has no delay slots. But let's keep the lenient stuff,
+           we might need it for something else in the future.  */
+        if (lenient && 0)
+          continue;
+
+        if ((inst & 0xffff0000) == 0x27bb0000) /* ldah $gp,n($t12) */
+	  continue;
+        if ((inst & 0xffff0000) == 0x23bd0000) /* lda $gp,n($gp) */
+            continue;
+        if ((inst & 0xffff0000) == 0x23de0000) /* lda $sp,n($sp) */
+            continue;
+        else if ((inst & 0xfc1f0000) == 0xb41e0000
+                 && (inst & 0xffff0000) != 0xb7fe0000)
+            continue;				/* stq reg,n($sp) */
+						/* reg != $zero */
+        else if ((inst & 0xfc1f0000) == 0x9c1e0000
+                 && (inst & 0xffff0000) != 0x9ffe0000)
+            continue;				/* stt reg,n($sp) */
+						/* reg != $zero */
+        else if (inst == 0x47de040f)            /* bis sp,sp,fp */
+            continue;
+        else
+            break;
+	    }
+    return pc + offset;
+#endif /* 0 */
+}
+
+/* Put here the code to store, into a struct frame_saved_regs,
+   the addresses of the saved registers of frame described by FRAME_INFO.
+   This includes special registers such as pc and fp saved in special
+   ways in the stack frame.  sp is even more special:
+   the address we return for it IS the sp for the next frame.  */
+
+void
+hppa_frame_find_saved_regs (frame_info, frame_saved_regs)
+     struct frame_info *frame_info;
+     struct frame_saved_regs *frame_saved_regs;
+{
+  CORE_ADDR pc;
+  struct unwind_table_entry *u;
+  unsigned long inst, stack_remaining, save_gr, save_fr, save_rp, save_sp;
+  int status, i, reg;
+  char buf[4];
+  int fp_loc = -1;
+
+  /* Zero out everything.  */
+  memset (frame_saved_regs, '\0', sizeof (struct frame_saved_regs));
+
+  /* Call dummy frames always look the same, so there's no need to
+     examine the dummy code to determine locations of saved registers;
+     instead, let find_dummy_frame_regs fill in the correct offsets
+     for the saved registers.  */
+  if ((frame_info->pc >= frame_info->frame
+       && frame_info->pc <= (frame_info->frame + CALL_DUMMY_LENGTH
+			     + 32 * 4 +	 (NUM_REGS - FP0_REGNUM) * 8
+			     + 6 * 4)))	
+    find_dummy_frame_regs (frame_info, frame_saved_regs);
+
+  /* Interrupt handlers are special too.  They lay out the register
+     state in the exact same order as the register numbers in GDB.  */
+  if (pc_in_interrupt_handler (frame_info->pc))
+    {
+      for (i = 0; i < NUM_REGS; i++)
+	{
+	  /* SP is a little special.  */
+	  if (i == SP_REGNUM)
+	    frame_saved_regs->regs[SP_REGNUM]
+	      = read_memory_integer (frame_info->frame + SP_REGNUM * 4, 4);
+	  else
+	    frame_saved_regs->regs[i] = frame_info->frame + i * 4;
+	}
+      return;
+    }
+
+#ifdef FRAME_FIND_SAVED_REGS_IN_SIGTRAMP
+  /* Handle signal handler callers.  */
+  if (frame_info->signal_handler_caller)
+    {
+      FRAME_FIND_SAVED_REGS_IN_SIGTRAMP (frame_info, frame_saved_regs);
+      return;
+    }
+#endif
+
+  /* Get the starting address of the function referred to by the PC
+     saved in frame.  */
+  pc = get_pc_function_start (frame_info->pc);
+
+  /* Yow! */
+  u = find_unwind_entry (pc);
+  if (!u)
+    return;
+
+  /* This is how much of a frame adjustment we need to account for.  */
+  stack_remaining = u->Total_frame_size << 3;
+
+  /* Magic register saves we want to know about.  */
+  save_rp = u->Save_RP;
+  save_sp = u->Save_SP;
+
+  /* Turn the Entry_GR field into a bitmask.  */
+  save_gr = 0;
+  for (i = 3; i < u->Entry_GR + 3; i++)
+    {
+      /* Frame pointer gets saved into a special location.  */
+      if (u->Save_SP && i == FP_REGNUM)
+	continue;
+
+      save_gr |= (1 << i);
+    }
+
+  /* Turn the Entry_FR field into a bitmask too.  */
+  save_fr = 0;
+  for (i = 12; i < u->Entry_FR + 12; i++)
+    save_fr |= (1 << i);
+
+  /* The frame always represents the value of %sp at entry to the
+     current function (and is thus equivalent to the "saved" stack
+     pointer.  */
+  frame_saved_regs->regs[SP_REGNUM] = frame_info->frame;
+
+  /* Loop until we find everything of interest or hit a branch.
+
+     For unoptimized GCC code and for any HP CC code this will never ever
+     examine any user instructions.
+
+     For optimzied GCC code we're faced with problems.  GCC will schedule
+     its prologue and make prologue instructions available for delay slot
+     filling.  The end result is user code gets mixed in with the prologue
+     and a prologue instruction may be in the delay slot of the first branch
+     or call.
+
+     Some unexpected things are expected with debugging optimized code, so
+     we allow this routine to walk past user instructions in optimized
+     GCC code.  */
+  while (save_gr || save_fr || save_rp || save_sp || stack_remaining > 0)
+    {
+      status = target_read_memory (pc, buf, 4);
+      inst = extract_unsigned_integer (buf, 4);
+
+      /* Yow! */
+      if (status != 0)
+	return;
+
+      /* Note the interesting effects of this instruction.  */
+      stack_remaining -= prologue_inst_adjust_sp (inst);
+
+      /* There is only one instruction used for saving RP into the stack.  */
+      if (inst == 0x6bc23fd9)
+	{
+	  save_rp = 0;
+	  frame_saved_regs->regs[RP_REGNUM] = frame_info->frame - 20;
+	}
+
+      /* Just note that we found the save of SP into the stack.  The
+	 value for frame_saved_regs was computed above.  */
+      if ((inst & 0xffffc000) == 0x6fc10000)
+	save_sp = 0;
+
+      /* Account for general and floating-point register saves.  */
+      reg = inst_saves_gr (inst);
+      if (reg >= 3 && reg <= 18
+	  && (!u->Save_SP || reg != FP_REGNUM))
+	{
+	  save_gr &= ~(1 << reg);
+
+	  /* stwm with a positive displacement is a *post modify*.  */
+	  if ((inst >> 26) == 0x1b
+	      && extract_14 (inst) >= 0)
+	    frame_saved_regs->regs[reg] = frame_info->frame;
+	  else
+	    {
+	      /* Handle code with and without frame pointers.  */
+	      if (u->Save_SP)
+		frame_saved_regs->regs[reg]
+		  = frame_info->frame + extract_14 (inst);
+	      else
+		frame_saved_regs->regs[reg]
+		  = frame_info->frame + (u->Total_frame_size << 3)
+		    + extract_14 (inst);
+	    }
+	}
+
+
+      /* GCC handles callee saved FP regs a little differently.  
+
+	 It emits an instruction to put the value of the start of
+	 the FP store area into %r1.  It then uses fstds,ma with
+	 a basereg of %r1 for the stores.
+
+	 HP CC emits them at the current stack pointer modifying
+	 the stack pointer as it stores each register.  */
+
+      /* ldo X(%r3),%r1 or ldo X(%r30),%r1.  */
+      if ((inst & 0xffffc000) == 0x34610000
+	  || (inst & 0xffffc000) == 0x37c10000)
+	fp_loc = extract_14 (inst);
+	
+      reg = inst_saves_fr (inst);
+      if (reg >= 12 && reg <= 21)
+	{
+	  /* Note +4 braindamage below is necessary because the FP status
+	     registers are internally 8 registers rather than the expected
+	     4 registers.  */
+	  save_fr &= ~(1 << reg);
+	  if (fp_loc == -1)
+	    {
+	      /* 1st HP CC FP register store.  After this instruction
+		 we've set enough state that the GCC and HPCC code are
+		 both handled in the same manner.  */
+	      frame_saved_regs->regs[reg + FP4_REGNUM + 4] = frame_info->frame;
+	      fp_loc = 8;
+	    }
+	  else
+	    {
+	      frame_saved_regs->regs[reg + FP0_REGNUM + 4]
+		= frame_info->frame + fp_loc;
+	      fp_loc += 8;
+	    }
+	}
+
+      /* Quit if we hit any kind of branch.  This can happen if a prologue
+	 instruction is in the delay slot of the first call/branch.  */
+      if (is_branch (inst))
+	break;
+
+      /* Bump the PC.  */
+      pc += 4;
+    }
+}
+
+
+/* Exception handling support for the HP-UX ANSI C++ compiler.
+   The compiler (aCC) provides a callback for exception events;
+   GDB can set a breakpoint on this callback and find out what
+   exception event has occurred. */
+
+/* The name of the hook to be set to point to the callback function */
+static char HP_ACC_EH_notify_hook[]     = "__eh_notify_hook";
+/* The name of the function to be used to set the hook value */ 
+static char HP_ACC_EH_set_hook_value[]  = "__eh_set_hook_value";
+/* The name of the callback function in end.o */ 
+static char HP_ACC_EH_notify_callback[] = "__d_eh_notify_callback";
+/* Name of function in end.o on which a break is set (called by above) */ 
+static char HP_ACC_EH_break[]           = "__d_eh_break";
+/* Name of flag (in end.o) that enables catching throws */ 
+static char HP_ACC_EH_catch_throw[]     = "__d_eh_catch_throw";
+/* Name of flag (in end.o) that enables catching catching */ 
+static char HP_ACC_EH_catch_catch[]     = "__d_eh_catch_catch";
+/* The enum used by aCC */ 
+typedef enum {
+  __EH_NOTIFY_THROW,
+  __EH_NOTIFY_CATCH
+} __eh_notification;
+
+/* Is exception-handling support available with this executable? */
+static int hp_cxx_exception_support = 0;
+/* Has the initialize function been run? */
+int hp_cxx_exception_support_initialized = 0;
+/* Similar to above, but imported from breakpoint.c -- non-target-specific */
+extern int exception_support_initialized;
+/* Address of __eh_notify_hook */
+static CORE_ADDR eh_notify_hook_addr = NULL;
+/* Address of __d_eh_notify_callback */
+static CORE_ADDR eh_notify_callback_addr = NULL;
+/* Address of __d_eh_break */
+static CORE_ADDR eh_break_addr = NULL;
+/* Address of __d_eh_catch_catch */
+static CORE_ADDR eh_catch_catch_addr = NULL;
+/* Address of __d_eh_catch_throw */
+static CORE_ADDR eh_catch_throw_addr = NULL;
+/* Sal for __d_eh_break */
+static struct symtab_and_line * break_callback_sal = NULL;
+
+/* Code in end.c expects __d_pid to be set in the inferior,
+   otherwise __d_eh_notify_callback doesn't bother to call
+   __d_eh_break!  So we poke the pid into this symbol
+   ourselves.
+   0 => success
+   1 => failure  */ 
+int
+setup_d_pid_in_inferior ()
+{
+  CORE_ADDR anaddr;
+  struct minimal_symbol * msymbol;
+  char buf[4]; /* FIXME 32x64? */
+  
+  /* Slam the pid of the process into __d_pid; failing is only a warning!  */
+  msymbol = lookup_minimal_symbol ("__d_pid", NULL, symfile_objfile);
+  if (msymbol == NULL)
+    {
+      warning ("Unable to find __d_pid symbol in object file.");
+      warning ("Suggest linking executable with -g (links in /opt/langtools/lib/end.o).");
+      return 1;
+    }
+
+  anaddr = SYMBOL_VALUE_ADDRESS (msymbol);
+  store_unsigned_integer (buf, 4, inferior_pid); /* FIXME 32x64? */
+  if (target_write_memory (anaddr, buf, 4)) /* FIXME 32x64? */
+    {
+      warning ("Unable to write __d_pid");
+      warning ("Suggest linking executable with -g (links in /opt/langtools/lib/end.o).");
+      return 1;
+    }
+  return 0;
+}
+
+/* Initialize exception catchpoint support by looking for the
+   necessary hooks/callbacks in end.o, etc., and set the hook value to
+   point to the required debug function
+
+   Return 0 => failure
+          1 => success          */
+
+static int
+initialize_hp_cxx_exception_support ()
+{
+  struct symtabs_and_lines sals;
+  struct cleanup * old_chain;
+  struct cleanup * canonical_strings_chain = NULL;
+  int i;
+  char * addr_start;
+  char * addr_end = NULL;
+  char ** canonical = (char **) NULL;
+  int thread = -1;
+  struct symbol * sym = NULL;
+  struct minimal_symbol * msym = NULL;
+  struct objfile * objfile;
+  asection *shlib_info;
+
+  /* Detect and disallow recursion.  On HP-UX with aCC, infinite
+     recursion is a possibility because finding the hook for exception
+     callbacks involves making a call in the inferior, which means
+     re-inserting breakpoints which can re-invoke this code */
+
+  static int recurse = 0;  
+  if (recurse > 0) 
+    {
+      hp_cxx_exception_support_initialized = 0;
+      exception_support_initialized = 0;
+      return 0;
+    }
+
+  hp_cxx_exception_support = 0;
+
+  /* First check if we have seen any HP compiled objects; if not,
+     it is very unlikely that HP's idiosyncratic callback mechanism
+     for exception handling debug support will be available!
+     This will percolate back up to breakpoint.c, where our callers
+     will decide to try the g++ exception-handling support instead. */
+  if (!hp_som_som_object_present)
+    return 0;
+  
+  /* We have a SOM executable with SOM debug info; find the hooks */
+
+  /* First look for the notify hook provided by aCC runtime libs */
+  /* If we find this symbol, we conclude that the executable must
+     have HP aCC exception support built in.  If this symbol is not
+     found, even though we're a HP SOM-SOM file, we may have been
+     built with some other compiler (not aCC).  This results percolates
+     back up to our callers in breakpoint.c which can decide to
+     try the g++ style of exception support instead.
+     If this symbol is found but the other symbols we require are
+     not found, there is something weird going on, and g++ support
+     should *not* be tried as an alternative.
+     
+     ASSUMPTION: Only HP aCC code will have __eh_notify_hook defined.  
+     ASSUMPTION: HP aCC and g++ modules cannot be linked together. */
+  
+  /* libCsup has this hook; it'll usually be non-debuggable */
+  msym = lookup_minimal_symbol (HP_ACC_EH_notify_hook, NULL, NULL);
+  if (msym)
+    {
+      eh_notify_hook_addr = SYMBOL_VALUE_ADDRESS (msym);
+      hp_cxx_exception_support = 1;
+    }  
+  else
+    {
+      warning ("Unable to find exception callback hook (%s).", HP_ACC_EH_notify_hook);
+      warning ("Executable may not have been compiled debuggable with HP aCC.");
+      warning ("GDB will be unable to intercept exception events.");
+      eh_notify_hook_addr = 0;
+      hp_cxx_exception_support = 0;
+      return 0;
+    }
+
+#if 0 /* DEBUGGING */
+  printf ("Hook addr found is %lx\n", eh_notify_hook_addr);
+#endif
+
+  /* Next look for the notify callback routine in end.o */
+  /* This is always available in the SOM symbol dictionary if end.o is linked in */ 
+  msym = lookup_minimal_symbol (HP_ACC_EH_notify_callback, NULL, NULL);
+  if (msym)
+    {
+      eh_notify_callback_addr = SYMBOL_VALUE_ADDRESS (msym);
+      hp_cxx_exception_support = 1;
+    }  
+  else 
+    {
+      warning ("Unable to find exception callback routine (%s).", HP_ACC_EH_notify_callback);
+      warning ("Suggest linking executable with -g (links in /opt/langtools/lib/end.o).");
+      warning ("GDB will be unable to intercept exception events.");
+      eh_notify_callback_addr = 0;
+      return 0;
+    }
+
+  /* Check whether the executable is dynamically linked or archive bound */
+  /* With an archive-bound executable we can use the raw addresses we find
+     for the callback function, etc. without modification. For an executable
+     with shared libraries, we have to do more work to find the plabel, which
+     can be the target of a call through $$dyncall from the aCC runtime support
+     library (libCsup) which is linked shared by default by aCC. */
+  /* This test below was copied from somsolib.c/somread.c.  It may not be a very
+     reliable one to test that an executable is linked shared. pai/1997-07-18 */ 
+  shlib_info = bfd_get_section_by_name (symfile_objfile->obfd, "$SHLIB_INFO$");
+  if (shlib_info && (bfd_section_size (symfile_objfile->obfd, shlib_info) != 0))
+    {
+      /* The minsym we have has the local code address, but that's not the
+         plabel that can be used by an inter-load-module call. */
+      /* Find solib handle for main image (which has end.o), and use that
+         and the min sym as arguments to __d_shl_get() (which does the equivalent
+         of shl_findsym()) to find the plabel. */ 
+
+      args_for_find_stub args;
+      static char message[] = "Error while finding exception callback hook:\n";
+      
+      args.solib_handle = som_solib_get_solib_by_pc (eh_notify_callback_addr);
+      args.msym = msym;
+      
+      recurse++;
+      eh_notify_callback_addr = catch_errors ((int (*) PARAMS ((char *))) cover_find_stub_with_shl_get,
+                                              (char *) &args,
+                                              message, RETURN_MASK_ALL);
+      recurse--;
+      
+#if 0 /* DEBUGGING  */
+      printf ("found plabel for eh notify callback: %x\n", eh_notify_callback_addr);
+#endif
+
+      exception_catchpoints_are_fragile = 1;
+      
+      if (!eh_notify_callback_addr)
+        {
+          /* We can get here either if there is no plabel in the export list
+             for the main image, or if something strange happened (??) */ 
+          warning ("Couldn't find a plabel (indirect function label) for the exception callback.");
+          warning ("GDB will not be able to intercept exception events.");
+          return 0;
+        }
+    }
+  else
+    exception_catchpoints_are_fragile = 0;
+
+#if 0  /* DEBUGGING */
+  printf ("Cb addr found is %lx\n", eh_notify_callback_addr);
+#endif
+
+  /* Now, look for the breakpointable routine in end.o */
+  /* This should also be available in the SOM symbol dict. if end.o linked in */ 
+  msym = lookup_minimal_symbol (HP_ACC_EH_break, NULL, NULL);
+  if (msym)
+    {
+      eh_break_addr = SYMBOL_VALUE_ADDRESS (msym);
+      hp_cxx_exception_support = 1;
+    }  
+  else
+    {
+      warning ("Unable to find exception callback routine to set breakpoint (%s).", HP_ACC_EH_break);
+      warning ("Suggest linking executable with -g (link in /opt/langtools/lib/end.o).");
+      warning ("GDB will be unable to intercept exception events.");
+      eh_break_addr = 0;
+      return 0;
+    }
+
+#if 0  /* DEBUGGING */
+  printf ("break addr found is %lx\n", eh_break_addr);  
+#endif
+  
+  /* Next look for the catch enable flag provided in end.o */
+  sym = lookup_symbol (HP_ACC_EH_catch_catch, (struct block *) NULL,
+                       VAR_NAMESPACE, 0, (struct symtab **) NULL);
+  if (sym) /* sometimes present in debug info */ 
+    {
+      eh_catch_catch_addr = SYMBOL_VALUE_ADDRESS (sym);
+      hp_cxx_exception_support = 1;
+    }
+  else  /* otherwise look in SOM symbol dict. */ 
+    {
+      msym = lookup_minimal_symbol (HP_ACC_EH_catch_catch, NULL, NULL);
+      if (msym)
+        {
+          eh_catch_catch_addr = SYMBOL_VALUE_ADDRESS (msym);
+          hp_cxx_exception_support = 1;
+        }  
+      else
+        {
+          warning ("Unable to enable interception of exception catches.");
+          warning ("Executable may not have been compiled debuggable with HP aCC.");
+          warning ("Suggest linking executable with -g (link in /opt/langtools/lib/end.o).");
+          return 0;
+        }
+    }
+
+#if 0  /* DEBUGGING */
+  printf ("catch catch addr found is %lx\n", eh_catch_catch_addr);
+#endif
+
+  /* Next look for the catch enable flag provided end.o */
+  sym = lookup_symbol (HP_ACC_EH_catch_catch, (struct block *) NULL,
+                       VAR_NAMESPACE, 0, (struct symtab **) NULL);
+  if (sym) /* sometimes present in debug info */ 
+    {
+      eh_catch_throw_addr = SYMBOL_VALUE_ADDRESS (sym);
+      hp_cxx_exception_support = 1;
+    }
+  else /* otherwise look in SOM symbol dict. */ 
+    {
+      msym = lookup_minimal_symbol (HP_ACC_EH_catch_throw, NULL, NULL);
+      if (msym)
+        {
+          eh_catch_throw_addr = SYMBOL_VALUE_ADDRESS (msym);
+          hp_cxx_exception_support = 1;
+        }  
+      else
+        {
+          warning ("Unable to enable interception of exception throws.");
+          warning ("Executable may not have been compiled debuggable with HP aCC.");
+          warning ("Suggest linking executable with -g (link in /opt/langtools/lib/end.o).");
+          return 0;
+        }
+    }
+
+#if 0  /* DEBUGGING */
+  printf ("catch throw addr found is %lx\n", eh_catch_throw_addr);
+#endif
+
+  /* Set the flags */ 
+  hp_cxx_exception_support = 2; /* everything worked so far */ 
+  hp_cxx_exception_support_initialized = 1;
+  exception_support_initialized = 1;
+
+  return 1;
+}
+
+/* Target operation for enabling or disabling interception of
+   exception events.
+   KIND is either EX_EVENT_THROW or EX_EVENT_CATCH
+   ENABLE is either 0 (disable) or 1 (enable).
+   Return value is NULL if no support found;
+   -1 if something went wrong,
+   or a pointer to a symtab/line struct if the breakpointable
+   address was found. */ 
+
+struct symtab_and_line * 
+child_enable_exception_callback (kind, enable)
+  enum exception_event_kind kind;
+  int enable;
+{
+  char buf[4];
+
+  if (!exception_support_initialized || !hp_cxx_exception_support_initialized)
+    if (!initialize_hp_cxx_exception_support ())
+      return NULL;
+
+  switch (hp_cxx_exception_support)
+    {
+      case 0:
+        /* Assuming no HP support at all */ 
+        return NULL;
+      case 1:
+        /* HP support should be present, but something went wrong */ 
+        return (struct symtab_and_line *) -1; /* yuck! */ 
+      /* there may be other cases in the future */ 
+    }
+        
+  /* Set the EH hook to point to the callback routine */
+  store_unsigned_integer (buf, 4, enable ? eh_notify_callback_addr : 0); /* FIXME 32x64 problem */
+  /* pai: (temp) FIXME should there be a pack operation first? */
+  if (target_write_memory (eh_notify_hook_addr, buf, 4))    /* FIXME 32x64 problem */
+    {
+      warning ("Could not write to target memory for exception event callback.");
+      warning ("Interception of exception events may not work.");
+      return (struct symtab_and_line *) -1; 
+    }
+  if (enable)
+    {
+      /* Ensure that __d_pid is set up correctly -- end.c code checks this. :-(*/
+      if (inferior_pid > 0)
+        {
+          if (setup_d_pid_in_inferior ())
+            return (struct symtab_and_line *) -1; 
+        }
+      else
+        {
+          warning ("Internal error: Invalid inferior pid?  Cannot intercept exception events."); /* purecov: deadcode */
+          return (struct symtab_and_line *) -1; /* purecov: deadcode */
+        }
+    }
+  
+  switch (kind)
+    {
+      case EX_EVENT_THROW:
+        store_unsigned_integer (buf, 4, enable ? 1 : 0);
+        if (target_write_memory (eh_catch_throw_addr, buf, 4)) /* FIXME 32x64? */
+          {
+            warning ("Couldn't enable exception throw interception.");
+            return (struct symtab_and_line *) -1;
+          }
+        break;
+      case EX_EVENT_CATCH:
+        store_unsigned_integer (buf, 4, enable ? 1 : 0);
+        if (target_write_memory (eh_catch_catch_addr, buf, 4)) /* FIXME 32x64? */
+          {
+            warning ("Couldn't enable exception catch interception.");
+            return (struct symtab_and_line *) -1;
+          }
+        break;
+      default: /* purecov: deadcode */
+        error ("Request to enable unknown or unsupported exception event."); /* purecov: deadcode */
+    }
+  
+  /* Copy break address into new sal struct, malloc'ing if needed. */
+  if (!break_callback_sal)
+    {
+      break_callback_sal = (struct symtab_and_line *) xmalloc (sizeof (struct symtab_and_line));
+    }
+  INIT_SAL(break_callback_sal);
+  break_callback_sal->symtab = NULL;
+  break_callback_sal->pc = eh_break_addr;
+  break_callback_sal->line = 0;
+  break_callback_sal->end = eh_break_addr;
+  
+  return break_callback_sal;
+}
+
+/* Record some information about the current exception event */ 
+static struct exception_event_record current_ex_event;
+/* Convenience struct */ 
+static struct symtab_and_line null_symtab_and_line = { NULL, 0, 0, 0 };
+
+/* Report current exception event.  Returns a pointer to a record
+   that describes the kind of the event, where it was thrown from,
+   and where it will be caught.  More information may be reported
+   in the future */ 
+struct exception_event_record *
+child_get_current_exception_event ()
+{
+  CORE_ADDR  event_kind;
+  CORE_ADDR  throw_addr;
+  CORE_ADDR  catch_addr;
+  struct frame_info *fi, *curr_frame;
+  int level = 1;
+
+  curr_frame = get_current_frame();
+  if (!curr_frame)
+    return (struct exception_event_record *) NULL;
+
+  /* Go up one frame to __d_eh_notify_callback, because at the
+     point when this code is executed, there's garbage in the
+     arguments of __d_eh_break. */
+  fi = find_relative_frame (curr_frame, &level);
+  if (level != 0)
+    return (struct exception_event_record *) NULL;
+
+  select_frame (fi, -1);
+
+  /* Read in the arguments */
+  /* __d_eh_notify_callback() is called with 3 arguments:
+          1. event kind catch or throw
+          2. the target address if known
+          3. a flag -- not sure what this is. pai/1997-07-17 */
+  event_kind = read_register (ARG0_REGNUM);  
+  catch_addr = read_register (ARG1_REGNUM);
+
+  /* Now go down to a user frame */
+  /* For a throw, __d_eh_break is called by
+                  __d_eh_notify_callback which is called by
+                  __notify_throw which is called
+                  from user code.
+     For a catch, __d_eh_break is called by
+                  __d_eh_notify_callback which is called by
+                  <stackwalking stuff> which is called by
+                  __throw__<stuff> or __rethrow_<stuff> which is called
+                  from user code. */
+  /* FIXME: Don't use such magic numbers; search for the frames */ 
+  level = (event_kind == EX_EVENT_THROW) ? 3 : 4;
+  fi = find_relative_frame (curr_frame, &level);
+  if (level != 0)
+    return (struct exception_event_record *) NULL;
+
+  select_frame (fi, -1);
+  throw_addr = fi->pc;
+
+  /* Go back to original (top) frame */
+  select_frame (curr_frame, -1);
+
+  current_ex_event.kind = (enum exception_event_kind) event_kind;
+  current_ex_event.throw_sal = find_pc_line (throw_addr, 1);
+  current_ex_event.catch_sal = find_pc_line (catch_addr, 1);
+
+  return &current_ex_event;
+}
+
+
+#ifdef MAINTENANCE_CMDS
+
+static void
+unwind_command (exp, from_tty)
+     char *exp;
+     int from_tty;
+{
+  CORE_ADDR address;
+  struct unwind_table_entry *u;
+
+  /* If we have an expression, evaluate it and use it as the address.  */
+
+  if (exp != 0 && *exp != 0)
+    address = parse_and_eval_address (exp);
+  else
+    return;
+
+  u = find_unwind_entry (address);
+
+  if (!u)
+    {
+      printf_unfiltered ("Can't find unwind table entry for %s\n", exp);
+      return;
+    }
+
+  printf_unfiltered ("unwind_table_entry (0x%x):\n", u);
+
+  printf_unfiltered ("\tregion_start = ");
+  print_address (u->region_start, gdb_stdout);
+
+  printf_unfiltered ("\n\tregion_end = ");
+  print_address (u->region_end, gdb_stdout);
+
+#ifdef __STDC__
+#define pif(FLD) if (u->FLD) printf_unfiltered (" "#FLD);
+#else
+#define pif(FLD) if (u->FLD) printf_unfiltered (" FLD");
+#endif
+
+  printf_unfiltered ("\n\tflags =");
+  pif (Cannot_unwind);
+  pif (Millicode);
+  pif (Millicode_save_sr0);
+  pif (Entry_SR);
+  pif (Args_stored);
+  pif (Variable_Frame);
+  pif (Separate_Package_Body);
+  pif (Frame_Extension_Millicode);
+  pif (Stack_Overflow_Check);
+  pif (Two_Instruction_SP_Increment);
+  pif (Ada_Region);
+  pif (Save_SP);
+  pif (Save_RP);
+  pif (Save_MRP_in_frame);
+  pif (extn_ptr_defined);
+  pif (Cleanup_defined);
+  pif (MPE_XL_interrupt_marker);
+  pif (HP_UX_interrupt_marker);
+  pif (Large_frame);
+
+  putchar_unfiltered ('\n');
+
+#ifdef __STDC__
+#define pin(FLD) printf_unfiltered ("\t"#FLD" = 0x%x\n", u->FLD);
+#else
+#define pin(FLD) printf_unfiltered ("\tFLD = 0x%x\n", u->FLD);
+#endif
+
+  pin (Region_description);
+  pin (Entry_FR);
+  pin (Entry_GR);
+  pin (Total_frame_size);
+}
+#endif /* MAINTENANCE_CMDS */
+
+#ifdef PREPARE_TO_PROCEED
+
+/* If the user has switched threads, and there is a breakpoint
+   at the old thread's pc location, then switch to that thread
+   and return TRUE, else return FALSE and don't do a thread
+   switch (or rather, don't seem to have done a thread switch).
+
+   Ptrace-based gdb will always return FALSE to the thread-switch
+   query, and thus also to PREPARE_TO_PROCEED.
+
+   The important thing is whether there is a BPT instruction,
+   not how many user breakpoints there are.  So we have to worry
+   about things like these:
+
+   o  Non-bp stop -- NO
+
+   o  User hits bp, no switch -- NO
+
+   o  User hits bp, switches threads -- YES
+
+   o  User hits bp, deletes bp, switches threads -- NO
+
+   o  User hits bp, deletes one of two or more bps
+      at that PC, user switches threads -- YES
+
+   o  Plus, since we're buffering events, the user may have hit a
+      breakpoint, deleted the breakpoint and then gotten another
+      hit on that same breakpoint on another thread which
+      actually hit before the delete. (FIXME in breakpoint.c
+      so that "dead" breakpoints are ignored?) -- NO
+
+   For these reasons, we have to violate information hiding and
+   call "breakpoint_here_p".  If core gdb thinks there is a bpt
+   here, that's what counts, as core gdb is the one which is
+   putting the BPT instruction in and taking it out. */
+int
+hppa_prepare_to_proceed()
+{
+  pid_t old_thread;
+  pid_t current_thread;
+
+  old_thread = hppa_switched_threads(inferior_pid);
+  if (old_thread != 0)
+    {
+      /* Switched over from "old_thread".  Try to do
+         as little work as possible, 'cause mostly
+         we're going to switch back. */
+      CORE_ADDR new_pc;
+      CORE_ADDR old_pc = read_pc();
+
+      /* Yuk, shouldn't use global to specify current
+         thread.  But that's how gdb does it. */
+      current_thread = inferior_pid;
+      inferior_pid   = old_thread;
+
+      new_pc = read_pc();
+      if (new_pc != old_pc          /* If at same pc, no need */
+	  && breakpoint_here_p (new_pc))
+        {
+	  /* User hasn't deleted the BP.
+             Return TRUE, finishing switch to "old_thread". */
+	  flush_cached_frames ();
+	  registers_changed ();
+#if 0
+	  printf("---> PREPARE_TO_PROCEED (was %d, now %d)!\n",
+		  current_thread, inferior_pid);
+#endif
+               
+	  return 1;
+        }
+
+      /* Otherwise switch back to the user-chosen thread. */
+      inferior_pid = current_thread;
+      new_pc       = read_pc();       /* Re-prime register cache */
+    }
+
+  return 0;
+}
+#endif /* PREPARE_TO_PROCEED */
+
+void
+_initialize_hppa_tdep ()
+{
+  tm_print_insn = print_insn_hppa;
+
+#ifdef MAINTENANCE_CMDS
+  add_cmd ("unwind", class_maintenance, unwind_command,
+	   "Print unwind table entry at given address.",
+	   &maintenanceprintlist);
+#endif /* MAINTENANCE_CMDS */
+}