コード例 #1
0
ファイル: draw_net_input.c プロジェクト: horsemma/iverilog
static char* draw_net_input_drive(ivl_nexus_t nex, ivl_nexus_ptr_t nptr)
{
      unsigned nptr_pin = ivl_nexus_ptr_pin(nptr);
      ivl_net_const_t cptr;
      ivl_net_logic_t lptr;
      ivl_signal_t sptr;
      ivl_lpm_t lpm;

      lptr = ivl_nexus_ptr_log(nptr);
      if (lptr
	  && ((ivl_logic_type(lptr)==IVL_LO_BUFZ)||(ivl_logic_type(lptr)==IVL_LO_BUFT))
	  && (nptr_pin == 0))
	    do {
		  if (! can_elide_bufz(lptr, nptr))
			break;

		  return strdup(draw_net_input(ivl_logic_pin(lptr, 1)));
	    } while(0);

      if (lptr && (ivl_logic_type(lptr) == IVL_LO_PULLDOWN)) {
	    return draw_net_pull(lptr, ivl_nexus_ptr_drive0(nptr), "0");
      }

      if (lptr && (ivl_logic_type(lptr) == IVL_LO_PULLUP)) {
	    return draw_net_pull(lptr, ivl_nexus_ptr_drive1(nptr), "1");
      }

      if (lptr && (nptr_pin == 0)) {
	    char tmp[128];
	    snprintf(tmp, sizeof tmp, "L_%p", lptr);
	    return strdup(tmp);
      }

      sptr = ivl_nexus_ptr_sig(nptr);
      if (sptr && (ivl_signal_type(sptr) == IVL_SIT_REG)) {
	    char tmp[128];
	      /* Input is a .var. This device may be a non-zero pin
	         because it may be an array of reg vectors. */
	    snprintf(tmp, sizeof tmp, "v%p_%u", sptr, nptr_pin);

	    if (ivl_signal_dimensions(sptr) > 0) {
		  fprintf(vvp_out, "v%p_%u .array/port v%p, %u;\n",
			  sptr, nptr_pin, sptr, nptr_pin);
	    }

	    return strdup(tmp);
      }

      cptr = ivl_nexus_ptr_con(nptr);
      if (cptr) {
	    char tmp[64];
	    char *result = 0;
	    ivl_expr_t d_rise, d_fall, d_decay;
            unsigned dly_width = 0;
	    char *dly;

	      /* Constants should have exactly 1 pin, with a literal value. */
	    assert(nptr_pin == 0);

	    switch (ivl_const_type(cptr)) {
		case IVL_VT_LOGIC:
		case IVL_VT_BOOL:
		case IVL_VT_STRING:
		  if ((ivl_nexus_ptr_drive0(nptr) == IVL_DR_STRONG)
		      && (ivl_nexus_ptr_drive1(nptr) == IVL_DR_STRONG)) {

			result = draw_C4_to_string(cptr);

		  } else {
			result = draw_C8_to_string(cptr,
						   ivl_nexus_ptr_drive0(nptr),
						   ivl_nexus_ptr_drive1(nptr));
		  }
                  dly_width = ivl_const_width(cptr);
		  break;

		case IVL_VT_REAL:
		  result = draw_Cr_to_string(ivl_const_real(cptr));
                  dly_width = 0;
		  break;

		default:
		  assert(0);
		  break;
	    }

	    d_rise = ivl_const_delay(cptr, 0);
	    d_fall = ivl_const_delay(cptr, 1);
	    d_decay = ivl_const_delay(cptr, 2);

	    dly = "";
	    if (d_rise != 0) {
		  draw_delay(cptr, dly_width, 0, d_rise, d_fall, d_decay);
		  dly = "/d";
	    }
	    fprintf(vvp_out, "L_%p%s .functor BUFT 1, %s, C4<0>, C4<0>, C4<0>;\n",
		    cptr, dly, result);
	    free(result);

	    snprintf(tmp, sizeof tmp, "L_%p", cptr);
	    return strdup(tmp);
      }

      lpm = ivl_nexus_ptr_lpm(nptr);
      if (lpm) switch (ivl_lpm_type(lpm)) {

	  case IVL_LPM_FF:
	  case IVL_LPM_LATCH:
	  case IVL_LPM_ABS:
	  case IVL_LPM_ADD:
	  case IVL_LPM_ARRAY:
	  case IVL_LPM_CAST_INT2:
	  case IVL_LPM_CAST_INT:
	  case IVL_LPM_CAST_REAL:
	  case IVL_LPM_CONCAT:
	  case IVL_LPM_CONCATZ:
	  case IVL_LPM_CMP_EEQ:
	  case IVL_LPM_CMP_EQ:
	  case IVL_LPM_CMP_WEQ:
	  case IVL_LPM_CMP_WNE:
	  case IVL_LPM_CMP_EQX:
	  case IVL_LPM_CMP_EQZ:
	  case IVL_LPM_CMP_GE:
	  case IVL_LPM_CMP_GT:
	  case IVL_LPM_CMP_NE:
	  case IVL_LPM_CMP_NEE:
	  case IVL_LPM_RE_AND:
	  case IVL_LPM_RE_OR:
	  case IVL_LPM_RE_XOR:
	  case IVL_LPM_RE_NAND:
	  case IVL_LPM_RE_NOR:
	  case IVL_LPM_RE_XNOR:
	  case IVL_LPM_SFUNC:
	  case IVL_LPM_SHIFTL:
	  case IVL_LPM_SHIFTR:
	  case IVL_LPM_SIGN_EXT:
	  case IVL_LPM_SUB:
	  case IVL_LPM_MULT:
	  case IVL_LPM_MUX:
	  case IVL_LPM_POW:
	  case IVL_LPM_DIVIDE:
	  case IVL_LPM_MOD:
	  case IVL_LPM_UFUNC:
	  case IVL_LPM_PART_VP:
	  case IVL_LPM_PART_PV: /* NOTE: This is only a partial driver. */
	  case IVL_LPM_REPEAT:
	  case IVL_LPM_SUBSTITUTE:
	    if (ivl_lpm_q(lpm) == nex) {
		  char tmp[128];
		  snprintf(tmp, sizeof tmp, "L_%p", lpm);
		  return strdup(tmp);
	    }
	    break;

      }

      fprintf(stderr, "vvp.tgt error: no input to nexus.\n");
      assert(0);
      return strdup("C<z>");
}
コード例 #2
0
static char* draw_net_input_drive(ivl_nexus_t nex, ivl_nexus_ptr_t nptr)
{
      unsigned nptr_pin = ivl_nexus_ptr_pin(nptr);
      ivl_net_const_t cptr;
      ivl_net_logic_t lptr;
      ivl_signal_t sptr;
      ivl_lpm_t lpm;

      lptr = ivl_nexus_ptr_log(nptr);
      if (lptr
	  && ((ivl_logic_type(lptr)==IVL_LO_BUFZ)||(ivl_logic_type(lptr)==IVL_LO_BUFT))
	  && (nptr_pin == 0))
	    do {
		  if (! can_elide_bufz(lptr, nptr))
			break;

		  return strdup(draw_net_input(ivl_logic_pin(lptr, 1)));
	    } while(0);

	/* If this is a pulldown device, then there is a single pin
	   that drives a constant value to the entire width of the
	   vector. The driver normally drives a pull0 value, so a C8<>
	   constant is appropriate, but if the drive is really strong,
	   then we can draw a C4<> constant instead. */
      if (lptr && (ivl_logic_type(lptr) == IVL_LO_PULLDOWN)) {
	    if (ivl_nexus_ptr_drive0(nptr) == IVL_DR_STRONG) {
		  size_t result_len = ivl_logic_width(lptr) + 5;
		  char*result = malloc(result_len);
		  char*dp = result;
		  strcpy(dp, "C4<");
		  dp += strlen(dp);
		  str_repeat(dp, "0", ivl_logic_width(lptr));
		  dp += ivl_logic_width(lptr);
		  *dp++ = '>';
		  *dp = 0;
		  assert(dp >= result);
		  assert((unsigned)(dp - result) <= result_len);
		  return result;
	    } else {
		  char val[4];
		  size_t result_len = 3*ivl_logic_width(lptr) + 5;
		  char*result = malloc(result_len);
		  char*dp = result;

		  val[0] = "01234567"[ivl_nexus_ptr_drive0(nptr)];
		  val[1] = val[0];
		  val[2] = '0';
		  val[3] = 0;

		  strcpy(dp, "C8<");
		  dp += strlen(dp);
		  str_repeat(dp, val, ivl_logic_width(lptr));
		  dp += 3*ivl_logic_width(lptr);
		  *dp++ = '>';
		  *dp = 0;
		  assert(dp >= result);
		  assert((unsigned)(dp - result) <= result_len);
		  return result;
	    }
      }

      if (lptr && (ivl_logic_type(lptr) == IVL_LO_PULLUP)) {
	    char*result;
	    char tmp[32];
	    if (ivl_nexus_ptr_drive1(nptr) == IVL_DR_STRONG) {
		  size_t result_len = 5 + ivl_logic_width(lptr);
		  result = malloc(result_len);
		  char*dp = result;
		  strcpy(dp, "C4<");
		  dp += strlen(dp);
		  str_repeat(dp, "1", ivl_logic_width(lptr));
		  dp += ivl_logic_width(lptr);
		  *dp++ = '>';
		  *dp = 0;
		  assert(dp >= result);
		  assert((unsigned)(dp - result) <= result_len);

	    } else {
		  char val[4];
		  size_t result_len = 5 + 3*ivl_logic_width(lptr);
		  result = malloc(result_len);
		  char*dp = result;

		  val[0] = "01234567"[ivl_nexus_ptr_drive1(nptr)];
		  val[1] = val[0];
		  val[2] = '1';
		  val[3] = 0;

		  strcpy(dp, "C8<");
		  dp += strlen(dp);
		  str_repeat(dp, val, ivl_logic_width(lptr));
		  dp += 3*ivl_logic_width(lptr);
		  *dp++ = '>';
		  *dp = 0;
		  assert(dp >= result);
		  assert((unsigned)(dp - result) <= result_len);

	    }

	      /* Make the constant an argument to a BUFZ, which is
		 what we use to drive the PULLed value. */
	    fprintf(vvp_out, "L_%p .functor BUFT 1, %s, C4<0>, C4<0>, C4<0>;\n",
		    lptr, result);
	    snprintf(tmp, sizeof tmp, "L_%p", lptr);
	    result = realloc(result, strlen(tmp)+1);
	    strcpy(result, tmp);
	    return result;
      }

      if (lptr && (nptr_pin == 0)) {
	    char tmp[128];
	    snprintf(tmp, sizeof tmp, "L_%p", lptr);
	    return strdup(tmp);
      }

      sptr = ivl_nexus_ptr_sig(nptr);
      if (sptr && (ivl_signal_type(sptr) == IVL_SIT_REG)) {
	    char tmp[128];
	      /* Input is a .var. This device may be a non-zero pin
	         because it may be an array of reg vectors. */
	    snprintf(tmp, sizeof tmp, "v%p_%u", sptr, nptr_pin);

	    if (ivl_signal_dimensions(sptr) > 0) {
		  fprintf(vvp_out, "v%p_%u .array/port v%p, %u;\n",
			  sptr, nptr_pin, sptr, nptr_pin);
	    }

	    return strdup(tmp);
      }

      cptr = ivl_nexus_ptr_con(nptr);
      if (cptr) {
	    char *result = 0;
	    ivl_expr_t d_rise, d_fall, d_decay;
            unsigned dly_width = 0;

	      /* Constants should have exactly 1 pin, with a literal value. */
	    assert(nptr_pin == 0);

	    switch (ivl_const_type(cptr)) {
		case IVL_VT_LOGIC:
		case IVL_VT_BOOL:
		case IVL_VT_STRING:
		  if ((ivl_nexus_ptr_drive0(nptr) == IVL_DR_STRONG)
		      && (ivl_nexus_ptr_drive1(nptr) == IVL_DR_STRONG)) {

			result = draw_C4_to_string(cptr);

		  } else {
			result = draw_C8_to_string(cptr,
						   ivl_nexus_ptr_drive0(nptr),
						   ivl_nexus_ptr_drive1(nptr));
		  }
                  dly_width = ivl_const_width(cptr);
		  break;

		case IVL_VT_REAL:
		  result = draw_Cr_to_string(ivl_const_real(cptr));
                  dly_width = 0;
		  break;

		default:
		  assert(0);
		  break;
	    }

	    d_rise = ivl_const_delay(cptr, 0);
	    d_fall = ivl_const_delay(cptr, 1);
	    d_decay = ivl_const_delay(cptr, 2);

	      /* We have a delayed constant, so we need to build some code. */
	    if (d_rise != 0) {
		  char tmp[128];
		  fprintf(vvp_out, "L_%p/d .functor BUFT 1, %s, "
		                   "C4<0>, C4<0>, C4<0>;\n", cptr, result);
		  free(result);

		    /* Is this a fixed or variable delay? */
		  if (number_is_immediate(d_rise, 64, 0) &&
		      number_is_immediate(d_fall, 64, 0) &&
		      number_is_immediate(d_decay, 64, 0)) {

			assert(! number_is_unknown(d_rise));
			assert(! number_is_unknown(d_fall));
			assert(! number_is_unknown(d_decay));

			fprintf(vvp_out, "L_%p .delay %u "
				"(%" PRIu64 ",%" PRIu64 ",%" PRIu64 ") L_%p/d;\n",
			                 cptr, dly_width,
			                 get_number_immediate64(d_rise),
			                 get_number_immediate64(d_fall),
			                 get_number_immediate64(d_decay), cptr);

		  } else {
			ivl_signal_t sig;
			// We do not currently support calculating the decay
			// from the rise and fall variable delays.
			assert(d_decay != 0);
			assert(ivl_expr_type(d_rise) == IVL_EX_SIGNAL);
			assert(ivl_expr_type(d_fall) == IVL_EX_SIGNAL);
			assert(ivl_expr_type(d_decay) == IVL_EX_SIGNAL);

			fprintf(vvp_out, "L_%p .delay %u L_%p/d",
                                cptr, dly_width, cptr);

			sig = ivl_expr_signal(d_rise);
			assert(ivl_signal_dimensions(sig) == 0);
			fprintf(vvp_out, ", v%p_0", sig);

			sig = ivl_expr_signal(d_fall);
			assert(ivl_signal_dimensions(sig) == 0);
			fprintf(vvp_out, ", v%p_0", sig);

			sig = ivl_expr_signal(d_decay);
			assert(ivl_signal_dimensions(sig) == 0);
			fprintf(vvp_out, ", v%p_0;\n", sig);
		  }

		  snprintf(tmp, sizeof tmp, "L_%p", cptr);
		  result = strdup(tmp);

	    } else {
		  char tmp[64];
		  fprintf(vvp_out, "L_%p .functor BUFT 1, %s, "
			  "C4<0>, C4<0>, C4<0>;\n", cptr, result);
		  free(result);

		  snprintf(tmp, sizeof tmp, "L_%p", cptr);
		  result = strdup(tmp);
	    }

	    return result;
      }

      lpm = ivl_nexus_ptr_lpm(nptr);
      if (lpm) switch (ivl_lpm_type(lpm)) {

	  case IVL_LPM_FF:
	  case IVL_LPM_ABS:
	  case IVL_LPM_ADD:
	  case IVL_LPM_ARRAY:
	  case IVL_LPM_CAST_INT2:
	  case IVL_LPM_CAST_INT:
	  case IVL_LPM_CAST_REAL:
	  case IVL_LPM_CONCAT:
	  case IVL_LPM_CONCATZ:
	  case IVL_LPM_CMP_EEQ:
	  case IVL_LPM_CMP_EQ:
	  case IVL_LPM_CMP_GE:
	  case IVL_LPM_CMP_GT:
	  case IVL_LPM_CMP_NE:
	  case IVL_LPM_CMP_NEE:
	  case IVL_LPM_RE_AND:
	  case IVL_LPM_RE_OR:
	  case IVL_LPM_RE_XOR:
	  case IVL_LPM_RE_NAND:
	  case IVL_LPM_RE_NOR:
	  case IVL_LPM_RE_XNOR:
	  case IVL_LPM_SFUNC:
	  case IVL_LPM_SHIFTL:
	  case IVL_LPM_SHIFTR:
	  case IVL_LPM_SIGN_EXT:
	  case IVL_LPM_SUB:
	  case IVL_LPM_MULT:
	  case IVL_LPM_MUX:
	  case IVL_LPM_POW:
	  case IVL_LPM_DIVIDE:
	  case IVL_LPM_MOD:
	  case IVL_LPM_UFUNC:
	  case IVL_LPM_PART_VP:
	  case IVL_LPM_PART_PV: /* NOTE: This is only a partial driver. */
	  case IVL_LPM_REPEAT:
	    if (ivl_lpm_q(lpm) == nex) {
		  char tmp[128];
		  snprintf(tmp, sizeof tmp, "L_%p", lpm);
		  return strdup(tmp);
	    }
	    break;

      }

      fprintf(stderr, "vvp.tgt error: no input to nexus.\n");
      assert(0);
      return strdup("C<z>");
}
コード例 #3
0
ファイル: vvp_scope.c プロジェクト: gserdyuk/gnucap-icarus
static void draw_logic_in_scope(ivl_net_logic_t lptr)
{
      unsigned pdx;
      const char*ltype = "?";
      const char*lcasc = 0;
      char identity_val = '0';

      int need_delay_flag = ivl_logic_delay(lptr,0)? 1 : 0;

      unsigned vector_width = width_of_nexus(ivl_logic_pin(lptr, 0));

      ivl_drive_t str0, str1;

      int level;
      int ninp = ivl_logic_pins(lptr) - 1;
      typedef const char*const_charp;
      const_charp*input_strings = calloc(ninp, sizeof(const_charp));

      for (pdx = 0 ;  pdx < ninp ;  pdx += 1) {
	    ivl_nexus_t nex = ivl_logic_pin(lptr, pdx+1);
	    if (nex == 0) {
		    /* Only UDPs can have unconnected inputs. */
		  assert(ivl_logic_type(lptr) == IVL_LO_UDP);
		  input_strings[pdx] = 0;
	    } else {
		  input_strings[pdx] = draw_net_input(nex);
	    }
      }

      switch (ivl_logic_type(lptr)) {

          case IVL_LO_UDP:
	    free(input_strings);
	    draw_udp_in_scope(lptr);
	    return;

          case IVL_LO_BUFZ: {
		  /* Draw bufz objects, but only if the gate cannot
		     be elided. If I can elide it, then the
		     draw_nex_input will take care of it for me. */
		ivl_nexus_ptr_t nptr = ivl_logic_pin_ptr(lptr,0);

		ltype = "BUFZ";

		if (can_elide_bufz(lptr, nptr))
		      return;

		break;
	  }

	  case IVL_LO_PULLDOWN:
	  case IVL_LO_PULLUP:
	      /* Skip pullup and pulldown objects. Things that have
		 pull objects as inputs will instead generate the
		 appropriate C<?> symbol. */
	    free(input_strings);
	    return;

	  case IVL_LO_AND:
	    ltype = "AND";
	    identity_val = '1';
	    break;

	  case IVL_LO_BUF:
	    ltype = "BUF";
	    break;

	  case IVL_LO_BUFIF0:
	    ltype = "BUFIF0";
	    break;

	  case IVL_LO_BUFIF1:
	    ltype = "BUFIF1";
	    break;

	  case IVL_LO_NAND:
	    ltype = "NAND";
	    lcasc = "AND";
	    identity_val = '1';
	    break;

	  case IVL_LO_NOR:
	    ltype = "NOR";
	    lcasc = "OR";
	    break;

	  case IVL_LO_NOT:
	    ltype = "NOT";
	    break;

	  case IVL_LO_OR:
	    ltype = "OR";
	    break;

	  case IVL_LO_XNOR:
	    ltype = "XNOR";
	    lcasc = "XOR";
	    break;

	  case IVL_LO_XOR:
	    ltype = "XOR";
	    break;

	  case IVL_LO_CMOS:
	    ltype = "CMOS";
	    break;

	  case IVL_LO_PMOS:
	    ltype = "PMOS";
	    break;

	  case IVL_LO_NMOS:
	    ltype = "NMOS";
	    break;

	  case IVL_LO_RCMOS:
	    ltype = "RCMOS";
	    break;

	  case IVL_LO_RPMOS:
	    ltype = "RPMOS";
	    break;

	  case IVL_LO_RNMOS:
	    ltype = "RNMOS";
	    break;

	  case IVL_LO_NOTIF0:
	    ltype = "NOTIF0";
	    break;

	  case IVL_LO_NOTIF1:
	    ltype = "NOTIF1";
	    break;

	  default:
	    fprintf(stderr, "vvp.tgt: error: Unhandled logic type: %u\n",
		    ivl_logic_type(lptr));
	    ltype = "?";
	    break;
      }

      { ivl_nexus_t nex = ivl_logic_pin(lptr, 0);
        ivl_nexus_ptr_t nptr = 0;
        unsigned idx;
	for (idx = 0 ;  idx < ivl_nexus_ptrs(nex) ;  idx += 1) {
	      nptr = ivl_nexus_ptr(nex,idx);
	      if (ivl_nexus_ptr_log(nptr) != lptr)
		    continue;
	      if (ivl_nexus_ptr_pin(nptr) != 0)
		    continue;
	      break;
	}
        str0 = ivl_nexus_ptr_drive0(nptr);
	str1 = ivl_nexus_ptr_drive1(nptr);
      }

      if (!lcasc)
	lcasc = ltype;

	/* Get all the input label that I will use for parameters to
	   the functor that I create later. */
      ninp = ivl_logic_pins(lptr) - 1;
      input_strings = calloc(ninp, sizeof(char*));
      for (pdx = 0 ;  pdx < ninp ;  pdx += 1)
	    input_strings[pdx] = draw_net_input(ivl_logic_pin(lptr, pdx+1));

      level = 0;
      ninp = ivl_logic_pins(lptr) - 1;
      while (ninp) {
	    int inst;
	    for (inst = 0; inst < ninp; inst += 4) {
		  if (ninp > 4)
			fprintf(vvp_out, "L_%p/%d/%d .functor %s %u",
				lptr, level, inst, lcasc, vector_width);
		  else {
			fprintf(vvp_out, "L_%p%s .functor %s %u",
				lptr, need_delay_flag? "/d" : "",
				ltype, vector_width);

			if (str0 != IVL_DR_STRONG || str1 != IVL_DR_STRONG)
			      fprintf(vvp_out, " [%u %u]", str0, str1);

		  }
		  for (pdx = inst; pdx < ninp && pdx < inst+4 ; pdx += 1) {
			if (level) {
			      fprintf(vvp_out, ", L_%p/%d/%d",
				      lptr, level - 1, pdx*4);
			} else {
			      fprintf(vvp_out, ", %s", input_strings[pdx]);
			}
		  }
		  for ( ;  pdx < inst+4 ;  pdx += 1) {
			unsigned wdx;
			fprintf(vvp_out, ", C4<");
			for (wdx = 0 ; wdx < vector_width ;  wdx += 1)
			      fprintf(vvp_out, "%c", identity_val);
			fprintf(vvp_out, ">");
		  }

		  fprintf(vvp_out, ";\n");
	    }
	    if (ninp > 4)
		  ninp = (ninp+3) / 4;
	    else
		  ninp = 0;
	    level += 1;
      }

	/* Free the array of char*. The strings themselves are
	   persistent, held by the ivl_nexus_t objects. */
      free(input_strings);

	/* If there are delays, then draw the delay functor to carry
	   that delay. This is the final output. */
      if (need_delay_flag) {
	    ivl_expr_t rise_exp  = ivl_logic_delay(lptr,0);
	    ivl_expr_t fall_exp  = ivl_logic_delay(lptr,1);
	    ivl_expr_t decay_exp = ivl_logic_delay(lptr,2);

	    if (number_is_immediate(rise_exp,64,0)
		&& number_is_immediate(fall_exp,64,0)
		&& number_is_immediate(decay_exp,64,0)) {

		  fprintf(vvp_out, "L_%p .delay (%lu,%lu,%lu) L_%p/d;\n",
			  lptr, get_number_immediate(rise_exp),
			  get_number_immediate(rise_exp),
			  get_number_immediate(rise_exp), lptr);
	    } else {
		  ivl_signal_t sig;
		  assert(ivl_expr_type(rise_exp) == IVL_EX_SIGNAL);
		  assert(ivl_expr_type(fall_exp) == IVL_EX_SIGNAL);
		  assert(ivl_expr_type(decay_exp) == IVL_EX_SIGNAL);

		  fprintf(vvp_out, "L_%p .delay  L_%p/d", lptr, lptr);

		  sig = ivl_expr_signal(rise_exp);
		  assert(ivl_signal_dimensions(sig) == 0);
		  fprintf(vvp_out, ", v%p_0", sig);

		  sig = ivl_expr_signal(fall_exp);
		  assert(ivl_signal_dimensions(sig) == 0);
		  fprintf(vvp_out, ", v%p_0", sig);

		  sig = ivl_expr_signal(decay_exp);
		  assert(ivl_signal_dimensions(sig) == 0);
		  fprintf(vvp_out, ", v%p_0;\n", sig);
	    }
      }
}