old-cross-binutils/gdb/hppah-tdep.c

/* Machine-dependent code which would otherwise be in inflow.c and core.c,
   for GDB, the GNU debugger.  This code is for the HP PA-RISC cpu.
   Copyright 1986, 1987, 1989, 1990, 1991, 1992 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., 675 Mass Ave, Cambridge, MA 02139, USA.  */

#include "defs.h"
#include "frame.h"
#include "inferior.h"
#include "value.h"

/* For argument passing to the inferior */
#include "symtab.h"

#ifdef USG
#include <sys/types.h>
#endif

#include <sys/param.h>
#include <sys/dir.h>
#include <signal.h>
#include <sys/ioctl.h>

#ifdef COFF_ENCAPSULATE
#include "a.out.encap.h"
#else
#include <a.out.h>
#endif
#ifndef N_SET_MAGIC
#define N_SET_MAGIC(exec, val) ((exec).a_magic = (val))
#endif

/*#include <sys/user.h>		After a.out.h  */
#include <sys/file.h>
#include <sys/stat.h>
#include <machine/psl.h>
#include "wait.h"

#include "gdbcore.h"
#include "gdbcmd.h"
#include "target.h"


/* Last modification time of executable file.
   Also used in source.c to compare against mtime of a source file.  */

extern int exec_mtime;

/* Virtual addresses of bounds of the two areas of memory in the core file.  */

/* extern CORE_ADDR data_start; */
extern CORE_ADDR data_end;
extern CORE_ADDR stack_start;
extern CORE_ADDR stack_end;

/* Virtual addresses of bounds of two areas of memory in the exec file.
   Note that the data area in the exec file is used only when there is no core file.  */

extern CORE_ADDR text_start;
extern CORE_ADDR text_end;

extern CORE_ADDR exec_data_start;
extern CORE_ADDR exec_data_end;

/* Address in executable file of start of text area data.  */

extern int text_offset;

/* Address in executable file of start of data area data.  */

extern int exec_data_offset;

/* Address in core file of start of data area data.  */

extern int data_offset;

/* Address in core file of start of stack area data.  */

extern int stack_offset;

struct header file_hdr;
struct som_exec_auxhdr exec_hdr;

/* Routines to extract various sized constants out of hppa 
   instructions. */

/* This assumes that no garbage lies outside of the lower bits of 
   value. */

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! */

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 */



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 */

extract_3 (word)
     unsigned word;
{
  return GET_FIELD (word, 18, 18) << 2 | GET_FIELD (word, 16, 17);
}
       
extract_5_load (word)
     unsigned word;
{
  return low_sign_extend (word >> 16 & MASK_5, 5);
}

/* 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);
}

/* extract an 11 bit immediate field */

int
extract_11 (word)
     unsigned word;
{
  return low_sign_extend (word & MASK_11, 11);
}

/* extract a 14 bit immediate field */

int
extract_14 (word)
     unsigned word;
{
  return low_sign_extend (word & MASK_14, 14);
}

/* deposit a 14 bit constant in a word */

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 */

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 */

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 */

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;
}

/* extract a 17 bit constant from branch instructions, returning the
   19 bit signed value. */

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;
}

CORE_ADDR
frame_saved_pc (frame)
     FRAME frame;
{
  if (get_current_frame () == frame)
    {
      struct frame_saved_regs saved_regs;
      CORE_ADDR pc = get_frame_pc (frame);
      int flags;

      flags = read_register (FLAGS_REGNUM);
      get_frame_saved_regs (frame, &saved_regs);
      if (pc >= millicode_start && pc < millicode_end
	  || (flags & 2))	/* In system call? */
	return read_register (31) & ~3;
      else if (saved_regs.regs[RP_REGNUM])
	return read_memory_integer (saved_regs.regs[RP_REGNUM], 4) & ~3;
      else
	return read_register (RP_REGNUM) & ~3;
    }
  return read_memory_integer (frame->frame - 20, 4) & ~0x3;
}

/* To see if a frame chain is valid, see if the caller looks like it
   was compiled with gcc. */

int frame_chain_valid (chain, thisframe)
     FRAME_ADDR chain;
     FRAME thisframe;
{
  if (chain && (chain > 0x60000000))
    {
      CORE_ADDR pc = get_pc_function_start (FRAME_SAVED_PC (thisframe));

      if (inside_entry_file (pc))
	return 0;
      /* look for stw rp, -20(0,sp); copy 4,1; copy sp, 4 */
      if (read_memory_integer (pc, 4) == 0x6BC23FD9)			
	pc = pc + 4;							
      
      if (read_memory_integer (pc, 4) == 0x8040241 &&
	  read_memory_integer (pc + 4, 4) == 0x81E0244)			
	return 1;
      else
	return 0;
    }
  else
    return 0;
}

/* Some helper functions. gcc_p returns 1 if the function beginning at 
   pc appears to have been compiled with gcc. hpux_cc_p returns 1 if
   fn was compiled with hpux cc. gcc functions look like :

   stw     rp,-0x14(sp) ; optional
   or      r4,r0,r1
   or      sp,r0,r4
   stwm    r1,framesize(sp)

   hpux cc functions look like:

   stw     rp,-0x14(sp) ; optional.
   stwm    r3,framesiz(sp)
   */

gcc_p (pc)
     CORE_ADDR pc;
{
  if (read_memory_integer (pc, 4) == 0x6BC23FD9)			
    pc = pc + 4;							
      
  if (read_memory_integer (pc, 4) == 0x8040241 &&
      read_memory_integer (pc + 4, 4) == 0x81E0244)			
    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.
 */

int
push_dummy_frame ()
{
  register CORE_ADDR sp = read_register (SP_REGNUM);
  register int regnum;
  int int_buffer;
  double freg_buffer;
  /* Space for "arguments"; the RP goes in here. */
  sp += 48;
  int_buffer = read_register (RP_REGNUM) | 0x3;
  write_memory (sp - 20, (char *)&int_buffer, 4);
  int_buffer = read_register (FP_REGNUM);
  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, read_register (PCOQ_HEAD_REGNUM));
  sp = push_word (sp, read_register (PCSQ_HEAD_REGNUM));
  sp = push_word (sp, read_register (PCOQ_TAIL_REGNUM));
  sp = push_word (sp, read_register (PCSQ_TAIL_REGNUM));
  write_register (SP_REGNUM, sp);
}

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;
  frame_saved_regs->regs[3] = fp + 12;
  for (fp += 16, i = 5; i < 32; fp += 4, i++)
    frame_saved_regs->regs[i] = fp;
  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;  fp += 4;
  frame_saved_regs->regs[SAR_REGNUM] = fp;  fp += 4;
  frame_saved_regs->regs[PCOQ_HEAD_REGNUM] = fp;  fp +=4;
  frame_saved_regs->regs[PCSQ_HEAD_REGNUM] = fp;  fp +=4;
  frame_saved_regs->regs[PCOQ_TAIL_REGNUM] = fp;  fp +=4;
  frame_saved_regs->regs[PCSQ_TAIL_REGNUM] = fp;
}

int
hp_pop_frame ()
{
  register FRAME frame = get_current_frame ();
  register CORE_ADDR fp;
  register int regnum;
  struct frame_saved_regs fsr;
  struct frame_info *fi;
  double freg_buffer;
  fi = get_frame_info (frame);
  fp = fi->frame;
  get_frame_saved_regs (fi, &fsr);
  if (fsr.regs[IPSW_REGNUM])    /* Restoring a call dummy frame */
    hp_restore_pc_queue (&fsr);
  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 (fsr.regs[PCOQ_TAIL_REGNUM])
    write_register (PCOQ_TAIL_REGNUM,
                    read_memory_integer (fsr.regs[PCOQ_TAIL_REGNUM], 4));
  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);
  flush_cached_frames ();
  set_current_frame (create_new_frame (read_register (FP_REGNUM),
                                       read_pc ()));
}

/*
 * After returning to a dummy on the stack, restore the instruction
 * queue space registers. */

int
hp_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);
  int pid;
  WAITTYPE w;
  int insn_count;

  /* Advance past break instruction in the call dummy. */
  pc += 4;  write_register (PCOQ_HEAD_REGNUM, pc);
  pc += 4;  write_register (PCOQ_TAIL_REGNUM, pc);

  /*
   * 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++)
    {
      resume (1, 0);
      target_wait(&w);

      if (!WIFSTOPPED (w))
        {
          stop_signal = WTERMSIG (w);
          terminal_ours_for_output ();
          printf ("\nProgram terminated with signal %d, %s\n",
                  stop_signal, safe_strsignal (stop_signal));
          fflush (stdout);
          return 0;
        }
    }
  fetch_inferior_registers (-1);
  return 1;
}

CORE_ADDR
hp_push_arguments (nargs, args, sp, struct_return, struct_addr)
     int nargs;
     value *args;
     CORE_ADDR sp;
     int struct_return;
     CORE_ADDR struct_addr;
{
  /* array of arguments' offsets */
  int *offset = (int *)alloca(nargs);
  int cum = 0;
  int i, alignment;
  
  for (i = 0; i < nargs; i++)
    {
      cum += TYPE_LENGTH (VALUE_TYPE (args[i]));
      /* value must go at proper alignment. Assume alignment is a
	 power of two.*/
      alignment = hp_alignof (VALUE_TYPE (args[i]));
      if (cum % alignment)
	cum = (cum + alignment) & -alignment;
      offset[i] = -cum;
    }
  sp += min ((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;
}

/* return the alignment of a type in bytes. Structures have the maximum
   alignment required by their fields. */

int
hp_alignof (arg)
     struct type *arg;
{
  int max_align, align, i;
  switch (TYPE_CODE (arg))
    {
    case TYPE_CODE_PTR:
    case TYPE_CODE_INT:
    case TYPE_CODE_FLT:
      return TYPE_LENGTH (arg);
    case TYPE_CODE_ARRAY:
      return hp_alignof (TYPE_FIELD_TYPE (arg, 0));
    case TYPE_CODE_STRUCT:
    case TYPE_CODE_UNION:
      max_align = 2;
      for (i = 0; i < TYPE_NFIELDS (arg); i++)
	{
	  /* Bit fields have no real alignment. */
	  if (!TYPE_FIELD_BITPOS (arg, i))
	    {
	      align = hp_alignof (TYPE_FIELD_TYPE (arg, i));
	      max_align = max (max_align, align);
	    }
	}
      return max_align;
    default:
      return 4;
    }
}

/* Print the register regnum, or all registers if regnum is -1 */

pa_do_registers_info (regnum, fpregs)
     int regnum;
     int fpregs;
{
  char raw_regs [REGISTER_BYTES];
  int i;
  
  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 < FP0_REGNUM)
    {
      printf ("%s %x\n", reg_names[regnum], *(long *)(raw_regs +
						      REGISTER_BYTE (regnum)));
    }
  else
    pa_print_fp_reg (regnum);
}

pa_print_registers (raw_regs, regnum, fpregs)
     char *raw_regs;
     int regnum;
     int fpregs;
{
  int i;

  for (i = 0; i < 18; i++)
    printf ("%8.8s: %8x  %8.8s: %8x  %8.8s: %8x  %8.8s: %8x\n",
		     reg_names[i],
		     *(int *)(raw_regs + REGISTER_BYTE (i)),
		     reg_names[i + 18],
		     *(int *)(raw_regs + REGISTER_BYTE (i + 18)),
		     reg_names[i + 36],
		     *(int *)(raw_regs + REGISTER_BYTE (i + 36)),
		     reg_names[i + 54],
		     *(int *)(raw_regs + REGISTER_BYTE (i + 54)));

  if (fpregs)
    for (i = 72; i < NUM_REGS; i++)
      pa_print_fp_reg (i);
}

pa_print_fp_reg (i)
     int i;
{
  unsigned char raw_buffer[MAX_REGISTER_RAW_SIZE];
  unsigned char virtual_buffer[MAX_REGISTER_VIRTUAL_SIZE];
  REGISTER_TYPE val;

  /* Get the data in raw format, then convert also to virtual format.  */
  read_relative_register_raw_bytes (i, raw_buffer);
  REGISTER_CONVERT_TO_VIRTUAL (i, raw_buffer, virtual_buffer);

  fputs_filtered (reg_names[i], stdout);
  print_spaces_filtered (15 - strlen (reg_names[i]), stdout);

  val_print (REGISTER_VIRTUAL_TYPE (i), virtual_buffer, 0, stdout, 0,
	     1, 0, Val_pretty_default);
  printf_filtered ("\n");

}

/* Function calls that pass into a new compilation unit must pass through a
   small piece of code that does long format (`external' in HPPA parlance)
   jumps.  We figure out where the trampoline is going to end up, and return
   the PC of the final destination.  If we aren't in a trampoline, we just
   return NULL. */

CORE_ADDR
skip_trampoline_code (pc)
     CORE_ADDR pc;
{
  long inst0, inst1;

  inst0 = read_memory_integer (pc, 4);
  inst1 = read_memory_integer (pc+4, 4);

  if (   (inst0 & 0xffe00000) == 0x20200000 /* ldil xxx, r1 */
      && (inst1 & 0xffe0e002) == 0xe0202002) /* be,n yyy(sr4, r1) */
    pc = extract_21 (inst0) + extract_17 (inst1);
  else
    pc = NULL;

  return pc;
}