/* m32r simulator support code
   Copyright (C) 1996-2021 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 3 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, see <http://www.gnu.org/licenses/>.  */

/* This must come before any other includes.  */
#include "defs.h"

#define WANT_CPU m32rbf
#define WANT_CPU_M32RBF

#include "sim-main.h"
#include "cgen-mem.h"
#include "cgen-ops.h"
#include <stdlib.h>

/* Return the size of REGNO in bytes.  */

static int
m32rbf_register_size (int regno)
{
  return 4;
}

/* Decode gdb ctrl register number.  */

int
m32r_decode_gdb_ctrl_regnum (int gdb_regnum)
{
  switch (gdb_regnum)
    {
      case PSW_REGNUM : return H_CR_PSW;
      case CBR_REGNUM : return H_CR_CBR;
      case SPI_REGNUM : return H_CR_SPI;
      case SPU_REGNUM : return H_CR_SPU;
      case BPC_REGNUM : return H_CR_BPC;
      case BBPSW_REGNUM : return H_CR_BBPSW;
      case BBPC_REGNUM : return H_CR_BBPC;
      case EVB_REGNUM : return H_CR_CR5;
    }
  abort ();
}

/* The contents of BUF are in target byte order.  */

int
m32rbf_fetch_register (SIM_CPU *current_cpu, int rn, unsigned char *buf, int len)
{
  int size = m32rbf_register_size (rn);
  if (len != size)
    return -1;

  if (rn < 16)
    SETTWI (buf, m32rbf_h_gr_get (current_cpu, rn));
  else
    switch (rn)
      {
      case PSW_REGNUM :
      case CBR_REGNUM :
      case SPI_REGNUM :
      case SPU_REGNUM :
      case BPC_REGNUM :
      case BBPSW_REGNUM :
      case BBPC_REGNUM :
	SETTWI (buf, m32rbf_h_cr_get (current_cpu,
				      m32r_decode_gdb_ctrl_regnum (rn)));
	break;
      case PC_REGNUM :
	SETTWI (buf, m32rbf_h_pc_get (current_cpu));
	break;
      case ACCL_REGNUM :
	SETTWI (buf, GETLODI (m32rbf_h_accum_get (current_cpu)));
	break;
      case ACCH_REGNUM :
	SETTWI (buf, GETHIDI (m32rbf_h_accum_get (current_cpu)));
	break;
      default :
	return 0;
      }

  return size;
}

/* The contents of BUF are in target byte order.  */

int
m32rbf_store_register (SIM_CPU *current_cpu, int rn, unsigned char *buf, int len)
{
  int size = m32rbf_register_size (rn);
  if (len != size)
    return -1;

  if (rn < 16)
    m32rbf_h_gr_set (current_cpu, rn, GETTWI (buf));
  else
    switch (rn)
      {
      case PSW_REGNUM :
      case CBR_REGNUM :
      case SPI_REGNUM :
      case SPU_REGNUM :
      case BPC_REGNUM :
      case BBPSW_REGNUM :
      case BBPC_REGNUM :
	m32rbf_h_cr_set (current_cpu,
			 m32r_decode_gdb_ctrl_regnum (rn),
			 GETTWI (buf));
	break;
      case PC_REGNUM :
	m32rbf_h_pc_set (current_cpu, GETTWI (buf));
	break;
      case ACCL_REGNUM :
	{
	  DI val = m32rbf_h_accum_get (current_cpu);
	  SETLODI (val, GETTWI (buf));
	  m32rbf_h_accum_set (current_cpu, val);
	  break;
	}
      case ACCH_REGNUM :
	{
	  DI val = m32rbf_h_accum_get (current_cpu);
	  SETHIDI (val, GETTWI (buf));
	  m32rbf_h_accum_set (current_cpu, val);
	  break;
	}
      default :
	return 0;
      }

  return size;
}

USI
m32rbf_h_cr_get_handler (SIM_CPU *current_cpu, UINT cr)
{
  switch (cr)
    {
    case H_CR_PSW : /* psw */
      return (((CPU (h_bpsw) & 0xc1) << 8)
	      | ((CPU (h_psw) & 0xc0) << 0)
	      | GET_H_COND ());
    case H_CR_BBPSW : /* backup backup psw */
      return CPU (h_bbpsw) & 0xc1;
    case H_CR_CBR : /* condition bit */
      return GET_H_COND ();
    case H_CR_SPI : /* interrupt stack pointer */
      if (! GET_H_SM ())
	return CPU (h_gr[H_GR_SP]);
      else
	return CPU (h_cr[H_CR_SPI]);
    case H_CR_SPU : /* user stack pointer */
      if (GET_H_SM ())
	return CPU (h_gr[H_GR_SP]);
      else
	return CPU (h_cr[H_CR_SPU]);
    case H_CR_BPC : /* backup pc */
      return CPU (h_cr[H_CR_BPC]) & 0xfffffffe;
    case H_CR_BBPC : /* backup backup pc */
      return CPU (h_cr[H_CR_BBPC]) & 0xfffffffe;
    case 4 : /* ??? unspecified, but apparently available */
    case 5 : /* ??? unspecified, but apparently available */
      return CPU (h_cr[cr]);
    default :
      return 0;
    }
}

void
m32rbf_h_cr_set_handler (SIM_CPU *current_cpu, UINT cr, USI newval)
{
  switch (cr)
    {
    case H_CR_PSW : /* psw */
      {
	int old_sm = (CPU (h_psw) & 0x80) != 0;
	int new_sm = (newval & 0x80) != 0;
	CPU (h_bpsw) = (newval >> 8) & 0xff;
	CPU (h_psw) = newval & 0xff;
	SET_H_COND (newval & 1);
	/* When switching stack modes, update the registers.  */
	if (old_sm != new_sm)
	  {
	    if (old_sm)
	      {
		/* Switching user -> system.  */
		CPU (h_cr[H_CR_SPU]) = CPU (h_gr[H_GR_SP]);
		CPU (h_gr[H_GR_SP]) = CPU (h_cr[H_CR_SPI]);
	      }
	    else
	      {
		/* Switching system -> user.  */
		CPU (h_cr[H_CR_SPI]) = CPU (h_gr[H_GR_SP]);
		CPU (h_gr[H_GR_SP]) = CPU (h_cr[H_CR_SPU]);
	      }
	  }
	break;
      }
    case H_CR_BBPSW : /* backup backup psw */
      CPU (h_bbpsw) = newval & 0xff;
      break;
    case H_CR_CBR : /* condition bit */
      SET_H_COND (newval & 1);
      break;
    case H_CR_SPI : /* interrupt stack pointer */
      if (! GET_H_SM ())
	CPU (h_gr[H_GR_SP]) = newval;
      else
	CPU (h_cr[H_CR_SPI]) = newval;
      break;
    case H_CR_SPU : /* user stack pointer */
      if (GET_H_SM ())
	CPU (h_gr[H_GR_SP]) = newval;
      else
	CPU (h_cr[H_CR_SPU]) = newval;
      break;
    case H_CR_BPC : /* backup pc */
      CPU (h_cr[H_CR_BPC]) = newval;
      break;
    case H_CR_BBPC : /* backup backup pc */
      CPU (h_cr[H_CR_BBPC]) = newval;
      break;
    case 4 : /* ??? unspecified, but apparently available */
    case 5 : /* ??? unspecified, but apparently available */
      CPU (h_cr[cr]) = newval;
      break;
    default :
      /* ignore */
      break;
    }
}

/* Cover fns to access h-psw.  */

UQI
m32rbf_h_psw_get_handler (SIM_CPU *current_cpu)
{
  return (CPU (h_psw) & 0xfe) | (CPU (h_cond) & 1);
}

void
m32rbf_h_psw_set_handler (SIM_CPU *current_cpu, UQI newval)
{
  CPU (h_psw) = newval;
  CPU (h_cond) = newval & 1;
}

/* Cover fns to access h-accum.  */

DI
m32rbf_h_accum_get_handler (SIM_CPU *current_cpu)
{
  /* Sign extend the top 8 bits.  */
  DI r;
#if 1
  r = ANDDI (CPU (h_accum), MAKEDI (0xffffff, 0xffffffff));
  r = XORDI (r, MAKEDI (0x800000, 0));
  r = SUBDI (r, MAKEDI (0x800000, 0));
#else
  SI hi,lo;
  r = CPU (h_accum);
  hi = GETHIDI (r);
  lo = GETLODI (r);
  hi = ((hi & 0xffffff) ^ 0x800000) - 0x800000;
  r = MAKEDI (hi, lo);
#endif
  return r;
}

void
m32rbf_h_accum_set_handler (SIM_CPU *current_cpu, DI newval)
{
  CPU (h_accum) = newval;
}

#if WITH_PROFILE_MODEL_P

/* FIXME: Some of these should be inline or macros.  Later.  */

/* Initialize cycle counting for an insn.
   FIRST_P is non-zero if this is the first insn in a set of parallel
   insns.  */

void
m32rbf_model_insn_before (SIM_CPU *cpu, int first_p)
{
  M32R_MISC_PROFILE *mp = CPU_M32R_MISC_PROFILE (cpu);
  mp->cti_stall = 0;
  mp->load_stall = 0;
  if (first_p)
    {
      mp->load_regs_pending = 0;
      mp->biggest_cycles = 0;
    }
}

/* Record the cycles computed for an insn.
   LAST_P is non-zero if this is the last insn in a set of parallel insns,
   and we update the total cycle count.
   CYCLES is the cycle count of the insn.  */

void
m32rbf_model_insn_after (SIM_CPU *cpu, int last_p, int cycles)
{
  PROFILE_DATA *p = CPU_PROFILE_DATA (cpu);
  M32R_MISC_PROFILE *mp = CPU_M32R_MISC_PROFILE (cpu);
  unsigned long total = cycles + mp->cti_stall + mp->load_stall;

  if (last_p)
    {
      unsigned long biggest = total > mp->biggest_cycles ? total : mp->biggest_cycles;
      PROFILE_MODEL_TOTAL_CYCLES (p) += biggest;
      PROFILE_MODEL_CUR_INSN_CYCLES (p) = total;
    }
  else
    {
      /* Here we take advantage of the fact that !last_p -> first_p.  */
      mp->biggest_cycles = total;
      PROFILE_MODEL_CUR_INSN_CYCLES (p) = total;
    }

  /* Branch and load stall counts are recorded independently of the
     total cycle count.  */
  PROFILE_MODEL_CTI_STALL_CYCLES (p) += mp->cti_stall;
  PROFILE_MODEL_LOAD_STALL_CYCLES (p) += mp->load_stall;

  mp->load_regs = mp->load_regs_pending;
}

static INLINE void
check_load_stall (SIM_CPU *cpu, int regno)
{
  UINT h_gr = CPU_M32R_MISC_PROFILE (cpu)->load_regs;

  if (regno != -1
      && (h_gr & (1 << regno)) != 0)
    {
      CPU_M32R_MISC_PROFILE (cpu)->load_stall += 2;
      if (TRACE_INSN_P (cpu))
	cgen_trace_printf (cpu, " ; Load stall of 2 cycles.");
    }
}

int
m32rbf_model_m32r_d_u_exec (SIM_CPU *cpu, const IDESC *idesc,
			    int unit_num, int referenced,
			    INT sr, INT sr2, INT dr)
{
  check_load_stall (cpu, sr);
  check_load_stall (cpu, sr2);
  return idesc->timing->units[unit_num].done;
}

int
m32rbf_model_m32r_d_u_cmp (SIM_CPU *cpu, const IDESC *idesc,
			   int unit_num, int referenced,
			   INT src1, INT src2)
{
  check_load_stall (cpu, src1);
  check_load_stall (cpu, src2);
  return idesc->timing->units[unit_num].done;
}

int
m32rbf_model_m32r_d_u_mac (SIM_CPU *cpu, const IDESC *idesc,
			   int unit_num, int referenced,
			   INT src1, INT src2)
{
  check_load_stall (cpu, src1);
  check_load_stall (cpu, src2);
  return idesc->timing->units[unit_num].done;
}

int
m32rbf_model_m32r_d_u_cti (SIM_CPU *cpu, const IDESC *idesc,
			   int unit_num, int referenced,
			   INT sr)
{
  PROFILE_DATA *profile = CPU_PROFILE_DATA (cpu);
  int taken_p = (referenced & (1 << 1)) != 0;

  check_load_stall (cpu, sr);
  if (taken_p)
    {
      CPU_M32R_MISC_PROFILE (cpu)->cti_stall += 2;
      PROFILE_MODEL_TAKEN_COUNT (profile) += 1;
    }
  else
    PROFILE_MODEL_UNTAKEN_COUNT (profile) += 1;
  return idesc->timing->units[unit_num].done;
}

int
m32rbf_model_m32r_d_u_load (SIM_CPU *cpu, const IDESC *idesc,
			    int unit_num, int referenced,
			    INT sr, INT dr)
{
  CPU_M32R_MISC_PROFILE (cpu)->load_regs_pending |= (1 << dr);
  check_load_stall (cpu, sr);
  return idesc->timing->units[unit_num].done;
}

int
m32rbf_model_m32r_d_u_store (SIM_CPU *cpu, const IDESC *idesc,
			     int unit_num, int referenced,
			     INT src1, INT src2)
{
  check_load_stall (cpu, src1);
  check_load_stall (cpu, src2);
  return idesc->timing->units[unit_num].done;
}

int
m32rbf_model_test_u_exec (SIM_CPU *cpu, const IDESC *idesc,
			  int unit_num, int referenced)
{
  return idesc->timing->units[unit_num].done;
}

#endif /* WITH_PROFILE_MODEL_P */