gdb-3.1

1 files changed, 932 insertions, 0 deletions

diff --git a/gdb/sparc-dep.c b/gdb/sparc-dep.c
new file mode 100644
index 0000000..2d53a04
--- /dev/null
+++ b/gdb/sparc-dep.c
@@ -0,0 +1,932 @@
+/* Machine-dependent code which would otherwise be in inflow.c and core.c,
+   for GDB, the GNU debugger.
+   Copyright (C) 1986, 1987 Free Software Foundation, Inc.
+   This code is for the sparc cpu.
+
+GDB is distributed in the hope that it will be useful, but WITHOUT ANY
+WARRANTY.  No author or distributor accepts responsibility to anyone
+for the consequences of using it or for whether it serves any
+particular purpose or works at all, unless he says so in writing.
+Refer to the GDB General Public License for full details.
+
+Everyone is granted permission to copy, modify and redistribute GDB,
+but only under the conditions described in the GDB General Public
+License.  A copy of this license is supposed to have been given to you
+along with GDB so you can know your rights and responsibilities.  It
+should be in a file named COPYING.  Among other things, the copyright
+notice and this notice must be preserved on all copies.
+
+In other words, go ahead and share GDB, but don't try to stop
+anyone else from sharing it farther.  Help stamp out software hoarding!
+*/
+
+#include "defs.h"
+#include "param.h"
+#include "frame.h"
+#include "inferior.h"
+#include "obstack.h"
+#include "sparc-opcode.h"
+#include "gdbcore.h"
+
+#include <stdio.h>
+#include <sys/param.h>
+#include <sys/dir.h>
+#include <sys/user.h>
+#include <signal.h>
+#include <sys/ioctl.h>
+#include <fcntl.h>
+
+#include <sys/ptrace.h>
+#include <machine/reg.h>
+
+#include <a.out.h>
+#include <sys/file.h>
+#include <sys/stat.h>
+#include <sys/core.h>
+
+extern int errno;
+extern int attach_flag;
+
+/* This function simply calls ptrace with the given arguments.  
+   It exists so that all calls to ptrace are isolated in this 
+   machine-dependent file. */
+int
+call_ptrace (request, pid, arg3, arg4)
+     int request, pid, arg3, arg4;
+{
+  return ptrace (request, pid, arg3, arg4);
+}
+
+void
+kill_inferior ()
+{
+  if (remote_debugging)
+    return;
+  if (inferior_pid == 0)
+    return;
+  ptrace (8, inferior_pid, 0, 0);
+  wait (0);
+  inferior_died ();
+}
+
+/* This is used when GDB is exiting.  It gives less chance of error.*/
+
+void
+kill_inferior_fast ()
+{
+  if (remote_debugging)
+    return;
+  if (inferior_pid == 0)
+    return;
+  ptrace (8, inferior_pid, 0, 0);
+  wait (0);
+}
+
+/* Simulate single-step ptrace call for sun4.  Code written by Gary
+   Beihl (beihl@mcc.com).  */
+
+/* 
+ * Duplicated from breakpoint.c because (at least for now) this is a
+ * machine dependent routine.
+ */
+static char break_insn[] = BREAKPOINT;
+
+/* From infrun.c */
+extern int stop_after_trap, stop_after_attach;
+
+static CORE_ADDR next_pc, npc4, target;
+static int brknpc4, brktrg;
+typedef char binsn_quantum[sizeof break_insn];
+static binsn_quantum break_mem[3];
+
+/* Non-zero if we just simulated a single-step ptrace call.  This is
+   needed because we cannot remove the breakpoints in the inferior
+   process until after the `wait' in `wait_for_inferior'.  Used for
+   sun4. */
+
+int one_stepped;
+
+void
+single_step (signal)
+     int signal;
+{
+  branch_type br, isannulled();
+  CORE_ADDR pc;
+
+  next_pc = read_register (NPC_REGNUM);
+  npc4 = next_pc + 4; /* branch not taken */
+
+  if (!one_stepped)
+    {
+      /* Always set breakpoint for NPC.  */
+      read_memory (next_pc, break_mem[0], sizeof break_insn);
+      write_memory (next_pc, break_insn, sizeof break_insn);
+      /* printf ("set break at %x\n",next_pc); */
+
+      pc = read_register (PC_REGNUM);
+      br = isannulled (pc, &target);
+      brknpc4 = brktrg = 0;
+
+      if (br == bicca)
+	{
+	  /* Conditional annulled branch will either end up at
+	     npc (if taken) or at npc+4 (if not taken).  Trap npc+4.  */
+	  brknpc4 = 1;
+	  read_memory (npc4, break_mem[1], sizeof break_insn);
+	  write_memory (npc4, break_insn, sizeof break_insn);
+	}
+      else if (br == baa && target != next_pc)
+	{ 
+	  /* Unconditional annulled branch will always end up at
+	     the target. */
+	  brktrg = 1;
+	  read_memory (target, break_mem[2], sizeof break_insn);
+	  write_memory (target, break_insn, sizeof break_insn);
+	}
+
+      /* Let it go */
+      ptrace (7, inferior_pid, 1, signal);
+      one_stepped = 1;
+      return;
+    }
+  else
+    {
+      /* Remove breakpoints */
+      write_memory (next_pc, break_mem[0], sizeof break_insn);
+
+      if (brknpc4)
+	{
+	  write_memory (npc4, break_mem[1], sizeof break_insn);
+	}
+      if (brktrg)
+	{
+	  write_memory (target, break_mem[2], sizeof break_insn);
+	}
+      one_stepped = 0;
+    }
+}
+
+/* Resume execution of the inferior process.
+   If STEP is nonzero, single-step it.
+   If SIGNAL is nonzero, give it that signal.  */
+
+void
+resume (step, signal)
+     int step;
+     int signal;
+{
+  errno = 0;
+  if (remote_debugging)
+    remote_resume (step, signal);
+  else
+    {
+      /* Sparc doesn't have single step on ptrace */
+      if (step)
+	single_step (signal);
+      else
+	ptrace (7, inferior_pid, 1, signal);
+      if (errno)
+	perror_with_name ("ptrace");
+    }
+}
+
+#ifdef ATTACH_DETACH
+
+/* Start debugging the process whose number is PID.  */
+
+int
+attach (pid)
+     int pid;
+{
+  errno = 0;
+  ptrace (PTRACE_ATTACH, pid, 0, 0);
+  if (errno)
+    perror_with_name ("ptrace");
+  attach_flag = 1;
+  return pid;
+}
+
+/* Stop debugging the process whose number is PID
+   and continue it with signal number SIGNAL.
+   SIGNAL = 0 means just continue it.  */
+
+void
+detach (signal)
+     int signal;
+{
+  errno = 0;
+  ptrace (PTRACE_DETACH, inferior_pid, 1, signal);
+  if (errno)
+    perror_with_name ("ptrace");
+  attach_flag = 0;
+}
+#endif /* ATTACH_DETACH */
+
+void
+fetch_inferior_registers ()
+{
+  struct regs inferior_registers;
+  struct fp_status inferior_fp_registers;
+  extern char registers[];
+  int cwp;
+  struct rwindow local_and_ins;
+
+  if (remote_debugging)
+    remote_fetch_registers (registers);
+  else
+    {
+      ptrace (PTRACE_GETREGS, inferior_pid, &inferior_registers);
+      ptrace (PTRACE_GETFPREGS, inferior_pid, &inferior_fp_registers);
+
+      registers[REGISTER_BYTE (0)] = 0;
+      bcopy (&inferior_registers.r_g1, &registers[REGISTER_BYTE (1)], 15 * 4);
+      bcopy (&inferior_fp_registers, &registers[REGISTER_BYTE (FP0_REGNUM)],
+	     sizeof inferior_fp_registers.fpu_fr);
+      *(int *)&registers[REGISTER_BYTE (PS_REGNUM)] = inferior_registers.r_ps; 
+      *(int *)&registers[REGISTER_BYTE (PC_REGNUM)] = inferior_registers.r_pc;
+      *(int *)&registers[REGISTER_BYTE (NPC_REGNUM)] = inferior_registers.r_npc;
+      *(int *)&registers[REGISTER_BYTE (Y_REGNUM)] = inferior_registers.r_y;
+/*      *(int *)&registers[REGISTER_BYTE (RP_REGNUM)] =
+             inferior_registers.r_o7 + 8;
+      bcopy (&inferior_fp_registers.Fpu_fsr,
+	     &registers[REGISTER_BYTE (FPS_REGNUM)],
+	     sizeof (FPU_FSR_TYPE)); */
+
+      read_inferior_memory (inferior_registers.r_sp,
+			    &registers[REGISTER_BYTE (16)],
+			    16*4);
+    }
+}
+
+/* Store our register values back into the inferior.
+   If REGNO is -1, do this for all registers.
+   Otherwise, REGNO specifies which register (so we can save time).  */
+
+void
+store_inferior_registers (regno)
+     int regno;
+{
+  struct regs inferior_registers;
+  struct fp_status inferior_fp_registers;
+  extern char registers[];
+
+  if (remote_debugging)
+    remote_store_registers (registers);
+  else
+    {
+      int in_regs = 1, in_fpregs = 1, in_fparegs, in_cpregs = 1;
+  
+      if (regno >= 0)
+	if (FP0_REGNUM <= regno && regno <= FP0_REGNUM + 32)
+	  in_regs = 0;
+	else
+	  in_fpregs = 0;
+
+      if (in_regs)
+	{
+	  bcopy (&registers[REGISTER_BYTE (1)],
+		 &inferior_registers.r_g1, 15 * 4);
+
+	  inferior_registers.r_ps =
+	    *(int *)&registers[REGISTER_BYTE (PS_REGNUM)];
+	  inferior_registers.r_pc =
+	    *(int *)&registers[REGISTER_BYTE (PC_REGNUM)];
+	  inferior_registers.r_npc =
+	    *(int *)&registers[REGISTER_BYTE (NPC_REGNUM)];
+	  inferior_registers.r_y =
+	    *(int *)&registers[REGISTER_BYTE (Y_REGNUM)];
+
+	  write_inferior_memory (*(int *)&registers[REGISTER_BYTE (SP_REGNUM)],
+				 &registers[REGISTER_BYTE (16)],
+				 16*4);
+	}
+      if (in_fpregs)
+	{
+	  bcopy (&registers[REGISTER_BYTE (FP0_REGNUM)],
+		 &inferior_fp_registers,
+		 sizeof inferior_fp_registers.fpu_fr);
+
+  /*      bcopy (&registers[REGISTER_BYTE (FPS_REGNUM)],
+	         &inferior_fp_registers.Fpu_fsr,
+		 sizeof (FPU_FSR_TYPE));
+  ****/
+	}
+
+      if (in_regs)
+	ptrace (PTRACE_SETREGS, inferior_pid, &inferior_registers);
+      if (in_fpregs)
+	ptrace (PTRACE_SETFPREGS, inferior_pid, &inferior_fp_registers);
+    }
+}
+
+/* NOTE! I tried using PTRACE_READDATA, etc., to read and write memory
+   in the NEW_SUN_PTRACE case.
+   It ought to be straightforward.  But it appears that writing did
+   not write the data that I specified.  I cannot understand where
+   it got the data that it actually did write.  */
+
+/* Copy LEN bytes from inferior's memory starting at MEMADDR
+   to debugger memory starting at MYADDR. 
+   On failure (cannot read from inferior, usually because address is out
+   of bounds) returns the value of errno. */
+
+int
+read_inferior_memory (memaddr, myaddr, len)
+     CORE_ADDR memaddr;
+     char *myaddr;
+     int len;
+{
+  register int i;
+  /* Round starting address down to longword boundary.  */
+  register CORE_ADDR addr = memaddr & - sizeof (int);
+  /* Round ending address up; get number of longwords that makes.  */
+  register int count
+    = (((memaddr + len) - addr) + sizeof (int) - 1) / sizeof (int);
+  /* Allocate buffer of that many longwords.  */
+  register int *buffer = (int *) alloca (count * sizeof (int));
+  extern int errno;
+
+  /* Read all the longwords */
+  for (i = 0; i < count; i++, addr += sizeof (int))
+    {
+      errno = 0;
+      if (remote_debugging)
+	buffer[i] = remote_fetch_word (addr);
+      else
+	buffer[i] = ptrace (1, inferior_pid, addr, 0);
+      if (errno)
+	return errno;
+    }
+
+  /* Copy appropriate bytes out of the buffer.  */
+  bcopy ((char *) buffer + (memaddr & (sizeof (int) - 1)), myaddr, len);
+  return 0;
+}
+
+/* Copy LEN bytes of data from debugger memory at MYADDR
+   to inferior's memory at MEMADDR.
+   On failure (cannot write the inferior)
+   returns the value of errno.  */
+
+int
+write_inferior_memory (memaddr, myaddr, len)
+     CORE_ADDR memaddr;
+     char *myaddr;
+     int len;
+{
+  register int i;
+  /* Round starting address down to longword boundary.  */
+  register CORE_ADDR addr = memaddr & - sizeof (int);
+  /* Round ending address up; get number of longwords that makes.  */
+  register int count
+    = (((memaddr + len) - addr) + sizeof (int) - 1) / sizeof (int);
+  /* Allocate buffer of that many longwords.  */
+  register int *buffer = (int *) alloca (count * sizeof (int));
+  extern int errno;
+
+  /* Fill start and end extra bytes of buffer with existing memory data.  */
+
+  if (remote_debugging)
+    buffer[0] = remote_fetch_word (addr);
+  else
+    buffer[0] = ptrace (1, inferior_pid, addr, 0);
+
+  if (count > 1)
+    {
+      if (remote_debugging)
+	buffer[count - 1]
+	  = remote_fetch_word (addr + (count - 1) * sizeof (int));
+      else
+	buffer[count - 1]
+	  = ptrace (1, inferior_pid,
+		    addr + (count - 1) * sizeof (int), 0);
+    }
+
+  /* Copy data to be written over corresponding part of buffer */
+
+  bcopy (myaddr, (char *) buffer + (memaddr & (sizeof (int) - 1)), len);
+
+  /* Write the entire buffer.  */
+
+  for (i = 0; i < count; i++, addr += sizeof (int))
+    {
+      errno = 0;
+      if (remote_debugging)
+	remote_store_word (addr, buffer[i]);
+      else
+	ptrace (4, inferior_pid, addr, buffer[i]);
+      if (errno)
+	return errno;
+    }
+
+  return 0;
+}
+
+
+/* Machine-dependent code which would otherwise be in core.c */
+/* Work with core dump and executable files, for GDB. */
+
+/* Recognize COFF format systems because a.out.h defines AOUTHDR.  */
+#ifdef AOUTHDR
+#define COFF_FORMAT
+#endif
+ 
+#ifndef N_TXTADDR
+#define N_TXTADDR(hdr) 0
+#endif /* no N_TXTADDR */
+
+#ifndef N_DATADDR
+#define N_DATADDR(hdr) hdr.a_text
+#endif /* no N_DATADDR */
+
+/* Make COFF and non-COFF names for things a little more compatible
+   to reduce conditionals later.  */
+
+#ifdef COFF_FORMAT
+#define a_magic magic
+#endif
+
+#ifndef COFF_FORMAT
+#define AOUTHDR struct exec
+#endif
+
+extern char *sys_siglist[];
+
+/* Hook for `exec_file_command' command to call.  */
+
+extern void (*exec_file_display_hook) ();
+   
+#ifdef COFF_FORMAT
+/* various coff data structures */
+
+extern FILHDR file_hdr;
+extern SCNHDR text_hdr;
+extern SCNHDR data_hdr;
+
+#endif /* not COFF_FORMAT */
+
+/* a.out header saved in core file.  */
+  
+extern AOUTHDR core_aouthdr;
+
+/* a.out header of exec file.  */
+
+extern AOUTHDR exec_aouthdr;
+
+extern void validate_files ();
+
+void
+core_file_command (filename, from_tty)
+     char *filename;
+     int from_tty;
+{
+  int val;
+  extern char registers[];
+
+  /* Discard all vestiges of any previous core file
+     and mark data and stack spaces as empty.  */
+
+  if (corefile)
+    free (corefile);
+  corefile = 0;
+
+  if (corechan >= 0)
+    close (corechan);
+  corechan = -1;
+
+  data_start = 0;
+  data_end = 0;
+  stack_start = STACK_END_ADDR;
+  stack_end = STACK_END_ADDR;
+
+  /* Now, if a new core file was specified, open it and digest it.  */
+
+  if (filename)
+    {
+      if (have_inferior_p ())
+	error ("To look at a core file, you must kill the inferior with \"kill\".");
+      corechan = open (filename, O_RDONLY, 0);
+      if (corechan < 0)
+	perror_with_name (filename);
+
+      {
+	struct core corestr;
+
+	val = myread (corechan, &corestr, sizeof corestr);
+	if (val < 0)
+	  perror_with_name (filename);
+	if (corestr.c_magic != CORE_MAGIC)
+	  error ("\"%s\" does not appear to be a core dump file (magic 0x%x, expected 0x%x)",
+		 filename, corestr.c_magic, (int) CORE_MAGIC);
+	else if (sizeof (struct core) != corestr.c_len)
+	  error ("\"%s\" has an invalid struct core length (%d, expected %d)",
+		 filename, corestr.c_len, (int) sizeof (struct core));
+
+	/* Note that data_start and data_end don't depend on the exec file */
+        data_start = N_DATADDR (corestr.c_aouthdr);
+	data_end = data_start + corestr.c_dsize;
+	stack_start = stack_end - corestr.c_ssize;
+	data_offset = sizeof corestr;
+	stack_offset = sizeof corestr + corestr.c_dsize;
+
+	/* G0 *always* holds 0.  */
+	*(int *)&registers[REGISTER_BYTE (0)] = 0;
+	/* The globals and output registers.  */
+
+	bcopy (&corestr.c_regs.r_g1, ((int *) registers) + 1, 15 * 4);
+	*(int *)&registers[REGISTER_BYTE (PS_REGNUM)] = corestr.c_regs.r_ps;
+	*(int *)&registers[REGISTER_BYTE (PC_REGNUM)] = corestr.c_regs.r_pc;
+	*(int *)&registers[REGISTER_BYTE (NPC_REGNUM)] = corestr.c_regs.r_npc;
+	*(int *)&registers[REGISTER_BYTE (Y_REGNUM)] = corestr.c_regs.r_y;
+
+	/* My best guess at where to get the locals and input
+	   registers is exactly where they usually are, right above
+	   the stack pointer.  If the core dump was caused by a bus
+	   writing off the stack pointer (as is possible) then this
+	   won't work, but it's worth the try. */
+	{
+	  int sp;
+
+	  sp = *(int *)&registers[REGISTER_BYTE (SP_REGNUM)];
+	  lseek (corechan, sp - stack_start + stack_offset, L_SET);
+	  if (16 * 4 != myread (corechan,
+				&registers[REGISTER_BYTE (16)],
+				16 * 4))
+	    /* fprintf so user can still use gdb */
+	    fprintf (stderr, "Couldn't read input and local registers from core file\n");
+	}
+
+	bcopy (corestr.c_fpu.fpu_regs,
+	       &registers[REGISTER_BYTE (FP0_REGNUM)],
+	       sizeof corestr.c_fpu.fpu_regs);
+#ifdef FPU
+	bcopy (&corestr.c_fpu.fpu_fsr,
+	       &registers[REGISTER_BYTE (FPS_REGNUM)],
+	       sizeof (FPU_FSR_TYPE));
+#endif
+
+	bcopy (&corestr.c_aouthdr, &core_aouthdr, sizeof (struct exec));
+
+	printf ("Core file is from \"%s\".\n", corestr.c_cmdname);
+	if (corestr.c_signo > 0)
+	  printf ("Program terminated with signal %d, %s.\n",
+			corestr.c_signo,
+			corestr.c_signo < NSIG
+			? sys_siglist[corestr.c_signo]
+			: "(undocumented)");
+      }
+      if (filename[0] == '/')
+	corefile = savestring (filename, strlen (filename));
+      else
+	{
+	  corefile = concat (current_directory, "/", filename);
+	}
+
+      set_current_frame ( create_new_frame (read_register (FP_REGNUM),
+					    read_pc ()));
+      select_frame (get_current_frame (), 0);
+      validate_files ();
+    }
+  else if (from_tty)
+    printf ("No core file now.\n");
+}
+
+void
+exec_file_command (filename, from_tty)
+     char *filename;
+     int from_tty;
+{
+  int val;
+
+  /* Eliminate all traces of old exec file.
+     Mark text segment as empty.  */
+
+  if (execfile)
+    free (execfile);
+  execfile = 0;
+  text_start = 0;
+  text_end = 0;
+  exec_data_start = 0;
+  exec_data_end = 0;
+  if (execchan >= 0)
+    close (execchan);
+  execchan = -1;
+
+  /* Now open and digest the file the user requested, if any.  */
+
+  if (filename)
+    {
+      execchan = openp (getenv ("PATH"), 1, filename, O_RDONLY, 0,
+			&execfile);
+      if (execchan < 0)
+	perror_with_name (filename);
+
+#ifdef COFF_FORMAT
+      {
+	int aout_hdrsize;
+	int num_sections;
+
+	if (read_file_hdr (execchan, &file_hdr) < 0)
+	  error ("\"%s\": not in executable format.", execfile);
+
+	aout_hdrsize = file_hdr.f_opthdr;
+	num_sections = file_hdr.f_nscns;
+
+	if (read_aout_hdr (execchan, &exec_aouthdr, aout_hdrsize) < 0)
+	  error ("\"%s\": can't read optional aouthdr", execfile);
+
+	if (read_section_hdr (execchan, _TEXT, &text_hdr, num_sections) < 0)
+	  error ("\"%s\": can't read text section header", execfile);
+
+	if (read_section_hdr (execchan, _DATA, &data_hdr, num_sections) < 0)
+	  error ("\"%s\": can't read data section header", execfile);
+
+	text_start = exec_aouthdr.text_start;
+	text_end = text_start + exec_aouthdr.tsize;
+	text_offset = text_hdr.s_scnptr;
+	exec_data_start = exec_aouthdr.data_start;
+	exec_data_end = exec_data_start + exec_aouthdr.dsize;
+	exec_data_offset = data_hdr.s_scnptr;
+	exec_mtime = file_hdr.f_timdat;
+      }
+#else /* not COFF_FORMAT */
+      {
+	struct stat st_exec;
+	val = myread (execchan, &exec_aouthdr, sizeof (AOUTHDR));
+
+	if (val < 0)
+	  perror_with_name (filename);
+
+        text_start = N_TXTADDR (exec_aouthdr);
+        exec_data_start = N_DATADDR (exec_aouthdr);
+	text_offset = N_TXTOFF (exec_aouthdr);
+	exec_data_offset = N_TXTOFF (exec_aouthdr) + exec_aouthdr.a_text;
+
+	text_end = text_start + exec_aouthdr.a_text;
+        exec_data_end = exec_data_start + exec_aouthdr.a_data;
+
+	fstat (execchan, &st_exec);
+	exec_mtime = st_exec.st_mtime;
+      }
+#endif /* not COFF_FORMAT */
+
+      validate_files ();
+    }
+  else if (from_tty)
+    printf ("No exec file now.\n");
+
+  /* Tell display code (if any) about the changed file name.  */
+  if (exec_file_display_hook)
+    (*exec_file_display_hook) (filename);
+}
+
+/*
+ * Find the pc saved in frame FRAME.  
+ */
+CORE_ADDR
+frame_saved_pc (frame)
+     FRAME frame;
+{
+  CORE_ADDR prev_pc;
+
+  /* If it's at the bottom, the return value's stored in i7/rp */
+  if (get_current_frame () == frame)
+    prev_pc = GET_RWINDOW_REG (read_register (SP_REGNUM), rw_in[7]);
+  else
+    /* Wouldn't this always work?  This would allow this routine to
+       be completely a macro.  */
+    prev_pc = GET_RWINDOW_REG (frame->bottom, rw_in[7]);
+  
+  return PC_ADJUST (prev_pc);
+}
+
+/*
+ * Since an individual frame in the frame cache is defined by two
+ * arguments (a frame pointer and a stack pointer), we need two
+ * arguments to get info for an arbitrary stack frame.  This routine
+ * takes two arguments and makes the cached frames look as if these
+ * two arguments defined a frame on the cache.  This allows the rest
+ * of info frame to extract the important arguments without
+ * difficulty. 
+ */
+FRAME
+setup_arbitrary_frame (frame, stack)
+     FRAME_ADDR frame, stack;
+{
+  struct frame_info *fci;
+  FRAME fid = create_new_frame (frame, 0);
+
+  if (!fid)
+    fatal ("internal: create_new_frame returned invalid frame id");
+  
+  fid->bottom = stack;
+
+  return fid;
+}
+
+/* This code was written by Gary Beihl (beihl@mcc.com).
+   It was modified by Michael Tiemann (tiemann@corto.inria.fr).  */
+
+struct command_line *get_breakpoint_commands ();
+
+/*
+ * This routine appears to be passed a size by which to increase the
+ * stack.  It then executes a save instruction in the inferior to
+ * increase the stack by this amount.  Only the register window system
+ * should be affected by this; the program counter & etc. will not be.
+ *
+ * This instructions used for this purpose are:
+ *
+ * 	sethi %hi(0x0),g1                    *
+ * 	add g1,0x1ee0,g1                     *
+ * 	save sp,g1,sp                        
+ * 	sethi %hi(0x0),g1                    *
+ * 	add g1,0x1ee0,g1                     *
+ * 	t g0,0x1,o0
+ * 	sethi %hi(0x0),g0                    (nop)
+ *
+ *  I presume that these set g1 to be the negative of the size, do a
+ * save (putting the stack pointer at sp - size) and restore the
+ * original contents of g1.  A * indicates that the actual value of
+ * the instruction is modified below.
+ */
+static int save_insn_opcodes[] = {
+  0x03000000, 0x82007ee0, 0x9de38001, 0x03000000,
+  0x82007ee0, 0x91d02001, 0x01000000 };
+
+/* Neither do_save_insn or do_restore_insn save stack configuration
+   (since the stack is in an indeterminate state through the call to
+   each of them); that responsibility of the routine which calls them.  */
+
+void
+do_save_insn (size)
+     int size;
+{
+  int g1 = read_register (1);
+  CORE_ADDR sp = read_register (SP_REGNUM);
+  CORE_ADDR pc = read_register (PC_REGNUM);
+  CORE_ADDR npc = read_register (NPC_REGNUM);
+  CORE_ADDR fake_pc = sp - sizeof (save_insn_opcodes);
+  struct inferior_status inf_status;
+
+  save_inferior_status (&inf_status, 0); /* Don't restore stack info */
+  /*
+   * See above.
+   */
+  save_insn_opcodes[0] = 0x03000000 | ((-size >> 10) & 0x3fffff);
+  save_insn_opcodes[1] = 0x82006000 | (-size & 0x3ff);
+  save_insn_opcodes[3] = 0x03000000 | ((g1 >> 10) & 0x3fffff);
+  save_insn_opcodes[4] = 0x82006000 | (g1 & 0x3ff);
+  write_memory (fake_pc, save_insn_opcodes, sizeof (save_insn_opcodes));
+
+  clear_proceed_status ();
+  stop_after_trap = 1;
+  proceed (fake_pc, 0, 0);
+
+  write_register (PC_REGNUM, pc);
+  write_register (NPC_REGNUM, npc);
+  restore_inferior_status (&inf_status);
+}
+
+/*
+ * This routine takes a program counter value.  It restores the
+ * register window system to the frame above the current one, and sets
+ * the pc and npc to the correct values.
+ */
+
+/*    The following insns translate to:
+ 
+ 	restore
+ 	t g0,0x1,o0
+ 	sethi %hi(0x0), g0	*/
+
+static int restore_insn_opcodes[] = { 0x81e80000, 0x91d02001, 0x01000000 };
+
+void
+do_restore_insn (pc)
+     CORE_ADDR pc;
+{
+  CORE_ADDR sp = read_register (SP_REGNUM);
+  CORE_ADDR npc = pc + 4;
+  CORE_ADDR fake_pc = sp - sizeof (restore_insn_opcodes);
+  struct inferior_status inf_status;
+
+  save_inferior_status (&inf_status, 0); /* Don't restore stack info */
+
+  if (!pc)
+    abort();
+
+  write_memory (fake_pc, restore_insn_opcodes, sizeof (restore_insn_opcodes));
+
+  clear_proceed_status ();
+  stop_after_trap = 1;
+  proceed (fake_pc, 0, 0);
+
+  write_register (PC_REGNUM, pc);
+  write_register (NPC_REGNUM, npc);
+  restore_inferior_status (&inf_status);
+}
+
+/*
+ * This routine should be more specific in it's actions; making sure
+ * that it uses the same register in the initial prologue section.
+ */
+CORE_ADDR 
+skip_prologue (pc)
+     CORE_ADDR pc;
+{
+  union
+    {
+      union insn_fmt insn;
+      int i;
+    } x;
+  int dest = -1;
+
+  x.i = read_memory_integer (pc, 4);
+
+  /* Recognize sethi insn.  Record destination.  */
+  if (x.insn.sethi.op == 0
+      && x.insn.sethi.op2 == 4)
+    {
+      dest = x.insn.sethi.rd;
+      pc += 4;
+      x.i = read_memory_integer (pc, 4);
+    }
+
+  /* Recognizes an add immediate value to register to either %g1 or
+     the destination register recorded above.  Actually, this might
+     well recognize several different arithmetic operations.*/
+  if (x.insn.arith_imm.op == 2
+      && x.insn.arith_imm.i == 1
+      && (x.insn.arith_imm.rd == 1
+	  || x.insn.arith_imm.rd == dest))
+    {
+      pc += 4;
+      x.i = read_memory_integer (pc, 4);
+    }
+
+  /* This recognizes any SAVE insn.  But why do the XOR and then
+     the compare?  That's identical to comparing against 60 (as long
+     as there isn't any sign extension).  */
+  if (x.insn.arith.op == 2
+      && (x.insn.arith.op3 ^ 32) == 28)
+    {
+      pc += 4;
+      x.i = read_memory_integer (pc, 4);
+    }
+
+  /* Now we need to recognize stores into the frame from the input
+     registers.  This recognizes all non alternate stores of input
+     register, into a location offset from the frame pointer. */
+  while (x.insn.arith_imm.op == 3
+	 && (x.insn.arith_imm.op3 & 0x3c) == 4 	   /* Store, non-alt */
+	 && (x.insn.arith_imm.rd & 0x18) == 0x18   /* Input register */
+	 && x.insn.arith_imm.i == 1 		   /* Immediate mode */
+	 && x.insn.arith_imm.rs1 == 30 		   /* Off of frame pointer */
+	 && x.insn.arith_imm.simm >= 0x44	   /* Into reserved */
+	 && x.insn.arith_imm.simm < 0x5b)	   /* stack space. */
+    {
+      pc += 4;
+      x.i = read_memory_integer (pc, 4);
+    }
+  return pc;
+}
+
+/*
+ * Check instruction at "addr" to see if it is an annulled branch.
+ * All other instructions will go to NPC or will trap.
+ *
+ * Set *target if we find a candidate branch; set to zero if not.
+ */
+
+branch_type
+isannulled (addr,  target)
+     CORE_ADDR addr, *target;
+{
+  union insn_fmt instr;
+  branch_type val = not_branch;
+  long offset; /* Must be signed for sign-extend */
+
+  *target = 0;
+  instr.intval = read_memory_integer (addr, 4);
+  /* printf("intval = %x\n",instr.intval); */
+  switch (instr.op1.op1)
+    {
+    case 0:			/* Format 2 */
+      switch(instr.op2.op2)
+	{
+	case 2: case 6: case 7:		/* Bcc, FBcc, CBcc */
+	  if (instr.branch.cond == 8)
+	    val = instr.branch.a ? baa : ba;
+	  else
+	    val = instr.branch.a ? bicca : bicc;
+	  /* 22 bits, sign extended */
+	  offset = 4 * ((int) (instr.branch.disp << 10) >> 10);
+	  *target = addr + offset;
+	  break;
+	}
+      break;
+    }
+  /*printf("isannulled ret: %d\n",val); */
+  return val;
+}