path: root/sim/common/cgen-utils.c

/* Support code for various pieces of CGEN simulators.
   Copyright (C) 1996, 1997 Free Software Foundation, Inc.
   Contributed by Cygnus Support.

This file is part of GDB, the GNU debugger.

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, 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 "sim-main.h"
#include "dis-asm.h"
#include "cpu-opc.h"
#include "decode.h"

#define MEMOPS_DEFINE_INLINE
#include "cgen-mem.h"

#define SEMOPS_DEFINE_INLINE
#include "cgen-sem.h"

const char *mode_names[] = {
  "VM",
  "BI",
  "QI",
  "HI",
  "SI",
  "DI",
  "UBI",
  "UQI",
  "UHI",
  "USI",
  "UDI",
  "SF",
  "DF",
  "XF",
  "TF",
};

void
engine_halt (cpu, reason, sigrc)
     sim_cpu *cpu;
     enum exec_state reason;
     int sigrc;
{
  CPU_EXEC_STATE (cpu) = reason;
  CPU_HALT_SIGRC (cpu) = sigrc;

  longjmp (STATE_HALT_JMP_BUF (CPU_STATE (cpu)), 1);
}

void
engine_signal (cpu, sig)
     sim_cpu *cpu;
     enum sim_signal_type sig;
{
  engine_halt (cpu, EXEC_STATE_STOPPED, sig);
}

/* Convert SIM_SIGFOO to SIGFOO.  */

int
sim_signal_to_host (sig)
     int sig;
{
  switch (sig)
    {
    case SIM_SIGILL :
#ifdef SIGILL
      return SIGILL;
#endif
      break;

    case SIM_SIGTRAP :
#ifdef SIGTRAP
      return SIGTRAP;
#else
#ifdef _MSC_VER
      /* Wingdb uses this value.  */
      return 5;
#endif
#endif
      break;

    case SIM_SIGALIGN :
    case SIM_SIGACCESS :
#ifdef SIGSEGV
      return SIGSEGV;
#endif
      break;

    case SIM_SIGXCPU :
#ifdef SIGXCPU
      return SIGXCPU;
#endif
      break;
    }
  return 1;
}

/* FIXME: Add "no return" attribute to illegal insn handlers.
   They all call longjmp.  */
/* FIXME: May wish to call a target supplied routine which can then call
   sim_halt if it wants: to allow target to gain control for moment.  */

void
ex_illegal (SIM_CPU *cpu, PCADDR pc, insn_t insn, ARGBUF *abuf)
{
  abuf->length = CGEN_BASE_INSN_SIZE;
  abuf->addr = pc;
  /* Leave signalling to semantic fn.  */
}

void
exc_illegal (SIM_CPU *cpu, PCADDR pc, insn_t insn, ARGBUF *abuf)
{
  abuf->length = CGEN_BASE_INSN_SIZE;
  abuf->addr = pc;
  /* Leave signalling to semantic fn.  */
}

PCADDR
sem_illegal (current_cpu, sem_arg)
     SIM_CPU *current_cpu;
     struct argbuf *sem_arg;
{
  engine_halt (current_cpu, EXEC_STATE_SIGNALLED, SIM_SIGILL);
  return 0;
}

PCADDR
semc_illegal (current_cpu, sem_arg)
     SIM_CPU *current_cpu;
     struct scache *sem_arg;
{
  engine_halt (current_cpu, EXEC_STATE_SIGNALLED, SIM_SIGILL);
  return 0;
}

/* Disassembly support.
   ??? While executing an instruction, the insn has been decoded and all its
   fields have been extracted.  It is certainly possible to do the disassembly
   with that data.  This seems simpler, but maybe in the future the already
   extracted fields will be used.  */

/* Pseudo FILE object for strings.  */
typedef struct {
  char *buffer;
  char *current;
} SFILE;

/* sprintf to a "stream" */

static int
disasm_sprintf VPARAMS ((SFILE *f, const char *format, ...))
{
#ifndef __STDC__
  SFILE *f;
  const char *format;
#endif
  int n;
  va_list args;

  VA_START (args, format);
#ifndef __STDC__
  f = va_arg (args, SFILE *);
  format = va_arg (args, char *);
#endif
  vsprintf (f->current, format, args);
  f->current += n = strlen (f->current);
  va_end (args);
  return n;
}

void
sim_disassemble_insn (insn, abuf, pc, buf)
     const struct cgen_insn *insn;
     const struct argbuf *abuf;
     PCADDR pc;
     char *buf;
{
  int length;
  unsigned long insn_value;
  struct disassemble_info disasm_info;
  struct cgen_fields fields;
  SFILE sfile;
  char insn_buf[20];
  STATE state = current_state;

  sfile.buffer = sfile.current = buf;
  INIT_DISASSEMBLE_INFO (disasm_info, (FILE *) &sfile,
			 (fprintf_ftype) disasm_sprintf);
  disasm_info.endian =
    (bfd_big_endian (STATE_PROG_BFD (state)) ? BFD_ENDIAN_BIG
     : bfd_little_endian (STATE_PROG_BFD (state)) ? BFD_ENDIAN_LITTLE
     : BFD_ENDIAN_UNKNOWN);

/*  (*STATE_MEM_READ (state)) (state, pc, insn_buf, abuf->length);*/

  switch (abuf->length)
    {
    case 1 :
      insn_value = insn_buf[0];
      break;
    case 2 :
      insn_value = disasm_info.endian == BFD_ENDIAN_BIG ? bfd_getb16 (insn_buf) : bfd_getl16 (insn_buf);
      break;
    case 4 :
      insn_value = disasm_info.endian == BFD_ENDIAN_BIG ? bfd_getb32 (insn_buf) : bfd_getl32 (insn_buf);
      break;
    default:
      abort ();
    }

  length = (*CGEN_EXTRACT_FN (insn)) (insn, NULL, insn_value, &fields);
  if (length != abuf->length)
    {
      (*CGEN_PRINT_FN (insn)) (&disasm_info, insn, &fields, pc, length);
    }
  else
    {
      /* This shouldn't happen, but aborting is too drastic.  */
      strcpy (buf, "***unknown***");
    }
}

#ifdef DI_FN_SUPPORT

DI
make_struct_di (hi, lo)
     SI hi, lo;
{
  DI result;

  result.hi = hi;
  result.lo = lo;
  return result;
}

DI
ANDDI (a, b)
     DI a, b;
{
  SI ahi = GETHIDI (a);
  SI alo = GETLODI (a);
  SI bhi = GETHIDI (b);
  SI blo = GETLODI (b);
  return MAKEDI (ahi & bhi, alo & blo);
}

DI
ORDI (a, b)
     DI a, b;
{
  SI ahi = GETHIDI (a);
  SI alo = GETLODI (a);
  SI bhi = GETHIDI (b);
  SI blo = GETLODI (b);
  return MAKEDI (ahi | bhi, alo | blo);
}

DI
ADDDI (a, b)
     DI a, b;
{
  USI ahi = GETHIDI (a);
  USI alo = GETLODI (a);
  USI bhi = GETHIDI (b);
  USI blo = GETLODI (b);
  USI x = alo + blo;
  return MAKEDI (ahi + bhi + (x < alo), x);
}

DI
MULDI (a, b)
     DI a, b;
{
  USI ahi = GETHIDI (a);
  USI alo = GETLODI (a);
  USI bhi = GETHIDI (b);
  USI blo = GETLODI (b);
  USI rhi,rlo;
  USI x0, x1, x2, x3;

  x0 = alo * blo;
  x1 = alo * bhi;
  x2 = ahi * blo;
  x3 = ahi * bhi;

#define SI_TYPE_SIZE 32
#define BITS4 (SI_TYPE_SIZE / 4)
#define ll_B (1L << (SI_TYPE_SIZE / 2))
#define ll_lowpart(t) ((USI) (t) % ll_B)
#define ll_highpart(t) ((USI) (t) / ll_B)
  x1 += ll_highpart (x0);	/* this can't give carry */
  x1 += x2;			/* but this indeed can */
  if (x1 < x2)			/* did we get it? */
    x3 += ll_B;			/* yes, add it in the proper pos. */

  rhi = x3 + ll_highpart (x1);
  rlo = ll_lowpart (x1) * ll_B + ll_lowpart (x0);
  return MAKEDI (rhi + (alo * bhi) + (ahi * blo), rlo);
}

DI
SHLDI (val, shift)
     DI val;
     SI shift;
{
  USI hi = GETHIDI (val);
  USI lo = GETLODI (val);
  /* FIXME: Need to worry about shift < 0 || shift >= 32.  */
  return MAKEDI ((hi << shift) | (lo >> (32 - shift)), lo << shift);
}

DI
SLADI (val, shift)
     DI val;
     SI shift;
{
  SI hi = GETHIDI (val);
  USI lo = GETLODI (val);
  /* FIXME: Need to worry about shift < 0 || shift >= 32.  */
  return MAKEDI ((hi << shift) | (lo >> (32 - shift)), lo << shift);
}

DI
SRADI (val, shift)
     DI val;
     SI shift;
{
  SI hi = GETHIDI (val);
  USI lo = GETLODI (val);
  /* We use SRASI because the result is implementation defined if hi < 0.  */
  /* FIXME: Need to worry about shift < 0 || shift >= 32.  */
  return MAKEDI (SRASI (hi, shift), (hi << (32 - shift)) | (lo >> shift));
}

int
GEDI (a, b)
     DI a, b;
{
  SI ahi = GETHIDI (a);
  USI alo = GETLODI (a);
  SI bhi = GETHIDI (b);
  USI blo = GETLODI (b);
  if (ahi > bhi)
    return 1;
  if (ahi == bhi)
    return alo >= blo;
  return 0;
}

int
LEDI (a, b)
     DI a, b;
{
  SI ahi = GETHIDI (a);
  USI alo = GETLODI (a);
  SI bhi = GETHIDI (b);
  USI blo = GETLODI (b);
  if (ahi < bhi)
    return 1;
  if (ahi == bhi)
    return alo <= blo;
  return 0;
}

DI
CONVHIDI (val)
     HI val;
{
  if (val < 0)
    return MAKEDI (-1, val);
  else
    return MAKEDI (0, val);
}

DI
CONVSIDI (val)
     SI val;
{
  if (val < 0)
    return MAKEDI (-1, val);
  else
    return MAKEDI (0, val);
}

SI
CONVDISI (val)
     DI val;
{
  return GETLODI (val);
}

#endif /* DI_FN_SUPPORT */