interp.c

gdb-6.0 linux 下的调试工具

	      regs[0] = -1;
	    break;
	  case SYS_time:
	    regs[0] = get_now ();
	    break;
	  default:
	    regs[0] = -1;
	    break;
	  }
	regs[1] = callback->get_errno (callback);
	errno = perrno;
      }
      break;

    case 0xc3:
    case 255:
      raise_exception (SIGTRAP);
      if (i == 0xc3)
	return -2;
      break;
    }
  return 0;
}

void
control_c (sig, code, scp, addr)
     int sig;
     int code;
     char *scp;
     char *addr;
{
  raise_exception (SIGINT);
}

static int
div1 (R, iRn2, iRn1/*, T*/)
     int *R;
     int iRn1;
     int iRn2;
     /* int T;*/
{
  unsigned long tmp0;
  unsigned char old_q, tmp1;

  old_q = Q;
  SET_SR_Q ((unsigned char) ((0x80000000 & R[iRn1]) != 0));
  R[iRn1] <<= 1;
  R[iRn1] |= (unsigned long) T;

  switch (old_q)
    {
    case 0:
      switch (M)
	{
	case 0:
	  tmp0 = R[iRn1];
	  R[iRn1] -= R[iRn2];
	  tmp1 = (R[iRn1] > tmp0);
	  switch (Q)
	    {
	    case 0:
	      SET_SR_Q (tmp1);
	      break;
	    case 1:
	      SET_SR_Q ((unsigned char) (tmp1 == 0));
	      break;
	    }
	  break;
	case 1:
	  tmp0 = R[iRn1];
	  R[iRn1] += R[iRn2];
	  tmp1 = (R[iRn1] < tmp0);
	  switch (Q)
	    {
	    case 0:
	      SET_SR_Q ((unsigned char) (tmp1 == 0));
	      break;
	    case 1:
	      SET_SR_Q (tmp1);
	      break;
	    }
	  break;
	}
      break;
    case 1:
      switch (M)
	{
	case 0:
	  tmp0 = R[iRn1];
	  R[iRn1] += R[iRn2];
	  tmp1 = (R[iRn1] < tmp0);
	  switch (Q)
	    {
	    case 0:
	      SET_SR_Q (tmp1);
	      break;
	    case 1:
	      SET_SR_Q ((unsigned char) (tmp1 == 0));
	      break;
	    }
	  break;
	case 1:
	  tmp0 = R[iRn1];
	  R[iRn1] -= R[iRn2];
	  tmp1 = (R[iRn1] > tmp0);
	  switch (Q)
	    {
	    case 0:
	      SET_SR_Q ((unsigned char) (tmp1 == 0));
	      break;
	    case 1:
	      SET_SR_Q (tmp1);
	      break;
	    }
	  break;
	}
      break;
    }
  /*T = (Q == M);*/
  SET_SR_T (Q == M);
  /*return T;*/
}

static void
dmul (sign, rm, rn)
     int sign;
     unsigned int rm;
     unsigned int rn;
{
  unsigned long RnL, RnH;
  unsigned long RmL, RmH;
  unsigned long temp0, temp1, temp2, temp3;
  unsigned long Res2, Res1, Res0;

  RnL = rn & 0xffff;
  RnH = (rn >> 16) & 0xffff;
  RmL = rm & 0xffff;
  RmH = (rm >> 16) & 0xffff;
  temp0 = RmL * RnL;
  temp1 = RmH * RnL;
  temp2 = RmL * RnH;
  temp3 = RmH * RnH;
  Res2 = 0;
  Res1 = temp1 + temp2;
  if (Res1 < temp1)
    Res2 += 0x00010000;
  temp1 = (Res1 << 16) & 0xffff0000;
  Res0 = temp0 + temp1;
  if (Res0 < temp0)
    Res2 += 1;
  Res2 += ((Res1 >> 16) & 0xffff) + temp3;
  
  if (sign)
    {
      if (rn & 0x80000000)
	Res2 -= rm;
      if (rm & 0x80000000)
	Res2 -= rn;
    }

  MACH = Res2;
  MACL = Res0;
}

static void
macw (regs, memory, n, m, endianw)
     int *regs;
     unsigned char *memory;
     int m, n;
     int endianw;
{
  long tempm, tempn;
  long prod, macl, sum;

  tempm=RSWAT(regs[m]); regs[m]+=2;
  tempn=RSWAT(regs[n]); regs[n]+=2;

  macl = MACL;
  prod = (long)(short) tempm * (long)(short) tempn;
  sum = prod + macl;
  if (S)
    {
      if ((~(prod ^ macl) & (sum ^ prod)) < 0)
	{
	  /* MACH's lsb is a sticky overflow bit.  */
	  MACH |= 1;
	  /* Store the smallest negative number in MACL if prod is
	     negative, and the largest positive number otherwise.  */
	  sum = 0x7fffffff + (prod < 0);
	}
    }
  else
    {
      long mach;
      /* Add to MACH the sign extended product, and carry from low sum.  */
      mach = MACH + (-(prod < 0)) + ((unsigned long) sum < prod);
      /* Sign extend at 10:th bit in MACH.  */
      MACH = (mach & 0x1ff) | -(mach & 0x200);
    }
  MACL = sum;
}

static struct loop_bounds
get_loop_bounds (rs, re, memory, mem_end, maskw, endianw)
     int rs, re;
     unsigned char *memory, *mem_end;
     int maskw, endianw;
{
  struct loop_bounds loop;

  if (SR_RC)
    {
      if (RS >= RE)
	{
	  loop.start = PT2H (RE - 4);
	  SKIP_INSN (loop.start);
	  loop.end = loop.start;
	  if (RS - RE == 0)
	    SKIP_INSN (loop.end);
	  if (RS - RE <= 2)
	    SKIP_INSN (loop.end);
	  SKIP_INSN (loop.end);
	}
      else
	{
	  loop.start = PT2H (RS);
	  loop.end = PT2H (RE - 4);
	  SKIP_INSN (loop.end);
	  SKIP_INSN (loop.end);
	  SKIP_INSN (loop.end);
	  SKIP_INSN (loop.end);
	}
      if (loop.end >= mem_end)
	loop.end = PT2H (0);
    }
  else
    loop.end = PT2H (0);

  return loop;
}

static void
ppi_insn();

#include "ppi.c"

/* Set the memory size to the power of two provided. */

void
sim_size (power)
     int power;

{
  saved_state.asregs.msize = 1 << power;

  sim_memory_size = power;

  if (saved_state.asregs.memory)
    {
      free (saved_state.asregs.memory);
    }

  saved_state.asregs.memory =
    (unsigned char *) calloc (64, saved_state.asregs.msize / 64);

  if (!saved_state.asregs.memory)
    {
      fprintf (stderr,
	       "Not enough VM for simulation of %d bytes of RAM\n",
	       saved_state.asregs.msize);

      saved_state.asregs.msize = 1;
      saved_state.asregs.memory = (unsigned char *) calloc (1, 1);
    }
}

static void
init_dsp (abfd)
     struct bfd *abfd;
{
  int was_dsp = target_dsp;
  unsigned long mach = bfd_get_mach (abfd);

  if (mach == bfd_mach_sh_dsp || mach == bfd_mach_sh3_dsp)
    {
      int ram_area_size, xram_start, yram_start;
      int new_select;

      target_dsp = 1;
      if (mach == bfd_mach_sh_dsp)
	{
	  /* SH7410 (orig. sh-sdp):
	     4KB each for X & Y memory;
	     On-chip X RAM 0x0800f000-0x0800ffff
	     On-chip Y RAM 0x0801f000-0x0801ffff  */
	  xram_start = 0x0800f000;
	  ram_area_size = 0x1000;
	}
      if (mach == bfd_mach_sh3_dsp)
	{
	  /* SH7612:
	     8KB each for X & Y memory;
	     On-chip X RAM 0x1000e000-0x1000ffff
	     On-chip Y RAM 0x1001e000-0x1001ffff  */
	  xram_start = 0x1000e000;
	  ram_area_size = 0x2000;
	}
      yram_start = xram_start + 0x10000;
      new_select = ~(ram_area_size - 1);
      if (saved_state.asregs.xyram_select != new_select)
	{
	  saved_state.asregs.xyram_select = new_select;
	  free (saved_state.asregs.xmem);
	  free (saved_state.asregs.ymem);
	  saved_state.asregs.xmem = (unsigned char *) calloc (1, ram_area_size);
	  saved_state.asregs.ymem = (unsigned char *) calloc (1, ram_area_size);

	  /* Disable use of X / Y mmeory if not allocated.  */
	  if (! saved_state.asregs.xmem || ! saved_state.asregs.ymem)
	    {
	      saved_state.asregs.xyram_select = 0;
	      if (saved_state.asregs.xmem)
		free (saved_state.asregs.xmem);
	      if (saved_state.asregs.ymem)
		free (saved_state.asregs.ymem);
	    }
	}
      saved_state.asregs.xram_start = xram_start;
      saved_state.asregs.yram_start = yram_start;
      saved_state.asregs.xmem_offset = saved_state.asregs.xmem - xram_start;
      saved_state.asregs.ymem_offset = saved_state.asregs.ymem - yram_start;
    }
  else
    {
      target_dsp = 0;
      if (saved_state.asregs.xyram_select)
	{
	  saved_state.asregs.xyram_select = 0;
	  free (saved_state.asregs.xmem);
	  free (saved_state.asregs.ymem);
	}
    }

  if (! saved_state.asregs.xyram_select)
    {
      saved_state.asregs.xram_start = 1;
      saved_state.asregs.yram_start = 1;
    }

  if (target_dsp != was_dsp)
    {
      int i, tmp;

      for (i = sizeof sh_dsp_table - 1; i >= 0; i--)
	{
	  tmp = sh_jump_table[0xf000 + i];
	  sh_jump_table[0xf000 + i] = sh_dsp_table[i];
	  sh_dsp_table[i] = tmp;
	}
    }
}

static void
init_pointers ()
{
  host_little_endian = 0;
  *(char*)&host_little_endian = 1;
  host_little_endian &= 1;

  if (saved_state.asregs.msize != 1 << sim_memory_size)
    {
      sim_size (sim_memory_size);
    }

  if (saved_state.asregs.profile && !profile_file)
    {
      profile_file = fopen ("gmon.out", "wb");
      /* Seek to where to put the call arc data */
      nsamples = (1 << sim_profile_size);

      fseek (profile_file, nsamples * 2 + 12, 0);

      if (!profile_file)
	{
	  fprintf (stderr, "Can't open gmon.out\n");
	}
      else
	{
	  saved_state.asregs.profile_hist =
	    (unsigned short *) calloc (64, (nsamples * sizeof (short) / 64));
	}
    }
}

static void
dump_profile ()
{
  unsigned int minpc;
  unsigned int maxpc;
  unsigned short *p;
  int i;

  p = saved_state.asregs.profile_hist;
  minpc = 0;
  maxpc = (1 << sim_profile_size);

  fseek (profile_file, 0L, 0);
  swapout (minpc << PROFILE_SHIFT);
  swapout (maxpc << PROFILE_SHIFT);
  swapout (nsamples * 2 + 12);
  for (i = 0; i < nsamples; i++)
    swapout16 (saved_state.asregs.profile_hist[i]);

}

static void
gotcall (from, to)
     int from;
     int to;
{
  swapout (from);
  swapout (to);
  swapout (1);
}

#define MMASKB ((saved_state.asregs.msize -1) & ~0)

int
sim_stop (sd)
     SIM_DESC sd;
{
  raise_exception (SIGINT);
  return 1;
}

void
sim_resume (sd, step, siggnal)
     SIM_DESC sd;
     int step, siggnal;
{
  register unsigned char *insn_ptr;
  unsigned char *mem_end;
  struct loop_bounds loop;
  register int cycles = 0;
  register int stalls = 0;
  register int memstalls = 0;
  register int insts = 0;
  register int prevlock;
  register int thislock;
  register unsigned int doprofile;
  register int pollcount = 0;
  /* endianw is used for every insn fetch, hence it makes sense to cache it.
     endianb is used less often.  */
  register int endianw = global_endianw;

  int tick_start = get_now ();
  void (*prev) ();
  void (*prev_fpe) ();

  register unsigned char *jump_table = sh_jump_table;

  register int *R = &(saved_state.asregs.regs[0]);
  /*register int T;*/
#ifndef PR
  register int PR;
#endif

  register int maskb = ~((saved_state.asregs.msize - 1) & ~0);
  register int maskw = ~((saved_state.asregs.msize - 1) & ~1);
  register int maskl = ~((saved_state.asregs.msize - 1) & ~3);
  register unsigned char *memory;
  register unsigned int sbit = ((unsigned int) 1 << 31);

  prev = signal (SIGINT, control_c);
  prev_fpe = signal (SIGFPE, SIG_IGN);

  init_pointers ();
  saved_state.asregs.exception = 0;

  memory = saved_state.asregs.memory;
  mem_end = memory + saved_state.asregs.msize;

  loop = get_loop_bounds (RS, RE, memory, mem_end, maskw, endianw);
  insn_ptr = PT2H (saved_state.asregs.pc);
  CHECK_INSN_PTR (insn_ptr);

#ifndef PR
  PR = saved_state.asregs.sregs.named.pr;
#endif
  /*T = GET_SR () & SR_MASK_T;*/
  prevlock = saved_state.asregs.prevlock;
  thislock = saved_state.asregs.thislock;
  doprofile = saved_state.asregs.profile;

  /* If profiling not enabled, disable it by asking for
     profiles infrequently. */
  if (doprofile == 0)
    doprofile = ~0;

 loop:
  if (step && insn_ptr < saved_state.asregs.insn_end)
    {
      if (saved_state.asregs.exception)
	/* This can happen if we've already been single-stepping and
	   encountered a loop end.  */
	saved_state.asregs.insn_end = insn_ptr;
      else
	{
	  saved_state.asregs.exception = SIGTRAP;
	  saved_state.asregs.insn_end = insn_ptr + 2;
	}
    }

  while (insn_ptr < saved_state.asregs.insn_end)
    {
      register unsigned int iword = RIAT (insn_ptr);
      register unsigned int ult;
      register unsigned char *nip = insn_ptr + 2;

#ifndef ACE_FAST
      insts++;
#endif
    top:

#include "code.c"


      insn_ptr = nip;

      if (--pollcount < 0)
	{
	  pollcount = POLL_QUIT_INTERVAL;
	  if ((*callback->poll_quit) != NULL
	      && (*callback->poll_quit) (callback))
	    {
	      sim_stop (sd);
	    }	    
	}

#ifndef ACE_FAST
      prevlock = thislock;
      thislock = 30;
      cycles++;

      if (cycles >= doprofile)
	{

	  saved_state.asregs.cycles += doprofile;
	  cycles -= doprofile;
	  if (saved_state.asregs.profile_hist)
	    {
	      int n = PH2T (insn_ptr) >> PROFILE_SHIFT;
	      if (n < nsamples)
		{
		  int i = saved_state.asregs.profile_hist[n];
		  if (i < 65000)
		    saved_state.asregs.profile_hist[n] = i + 1;
		}

	    }
	}
#endif
    }
  if (saved_state.asregs.insn_end == loop.end)
    {
      saved_state.asregs.cregs.named.sr += SR_RC_INCREMENT;
      if (SR_RC)
	insn_ptr = loop.start;
      else
	{
	  saved_state.asregs.insn_end = mem_end;
	  loop.end = PT2H (0);
	}
      goto loop;