V0.9: Stopgap fix for br916.

Currently, when a variable expression is passed to a system task,
the expression value is stored in thread memory. Values stored
in thread memory cannot safely be passed to $strobe or $monitor,
because the thread memory may get reused or deallocated before
the $strobe or $monitor task actually executes. As a temporary
measure, we just trap this case and terminate with a "sorry"
message. A proper fix would require the expression value to be
calculated at the time the $strobe or $monitor executes, not at
the time it is called.

vpi/sys_display.c

@@ -1023,6 +1023,10 @@ static char *get_display(unsigned int *rtnsz, const struct strobe_cb_info *info)
   return rtn;
 }
 
+#ifdef BR916_STOPGAP_FIX
+static char br916_hint_issued = 0;
+#endif
+
 static int sys_check_args(vpiHandle callh, vpiHandle argv, const PLI_BYTE8*name,
                           int no_auto, int is_monitor)
 {
@@ -1060,6 +1064,31 @@ static int sys_check_args(vpiHandle callh, vpiHandle argv, const PLI_BYTE8*name,
 	      case vpiIntegerVar:
 	      case vpiTimeVar:
 	      case vpiRealVar:
+#ifdef BR916_STOPGAP_FIX
+		    // no_auto implies either $strobe or $monitor
+	          if (no_auto) {
+	  	    switch (vpi_get(_vpiFromThr, arg)) {
+		      case _vpiVThr:
+		      case _vpiWord:
+		      case _vpiString:
+	                vpi_printf("SORRY: %s:%d: ",
+				   vpi_get_str(vpiFile, callh),
+	                           (int)vpi_get(vpiLineNo, callh));
+	                vpi_printf("currently only simple signals or constant "
+                                   "expressions may be passed to %s.\n", name);
+			if (!br916_hint_issued) {
+			      vpi_printf("NOTE: You can work round this by "
+					 "assigning the desired expression "
+					 "to an intermediate net (using a "
+					 "continuous assignment) and passing "
+					 "that net to %s.\n", name);
+			}
+	                ret = 1;
+		      default:
+			break;
+		    }
+		  }
+#endif
 	      case vpiSysFuncCall:
 		  break;
 

vpi_user.h

@@ -584,6 +584,25 @@ extern void vpip_format_strength(char*str, s_vpi_value*value, unsigned bit);
 extern void vpip_set_return_value(int value);
 extern s_vpi_vecval vpip_calc_clog2(vpiHandle arg);
 
+/*
+ * Stopgap fix for br916. We need to reject any attempt to pass a thread
+ * variable to $strobe or $monitor. To do this, we use some private VPI
+ * properties that are normally only used by the VVP thread cleanup code.
+ * Normally the following definitions are provided by vvp/vpi_priv.h, but
+ * for the stopgap fix we need to make them more widely available.
+ */
+#define BR916_STOPGAP_FIX
+#ifdef BR916_STOPGAP_FIX
+#define _vpiFromThr 0x1000001
+#   define _vpiNoThr   0
+#   define _vpiString  1
+#   define _vpiVThr    2
+#   define _vpiWord    3
+#   define _vpi_at_PV  4
+#   define _vpi_at_A   5
+#   define _vpi_at_APV 6
+#endif
+
 EXTERN_C_END
 
 #endif

vvp/array.cc

@@ -507,7 +507,7 @@ static int vpi_array_var_word_get(int code, vpiHandle ref)
 	  case vpiAutomatic:
 	    return (int) parent->scope->is_automatic;
 
-#ifdef CHECK_WITH_VALGRIND
+#if defined(CHECK_WITH_VALGRIND) || defined(BR916_STOPGAP_FIX)
 	  case _vpiFromThr:
 	    return _vpiNoThr;
 #endif
@@ -699,7 +699,7 @@ static int vpi_array_vthr_A_get(int code, vpiHandle ref)
 	  case vpiAutomatic:
 	    return (int) parent->scope->is_automatic;
 
-#ifdef CHECK_WITH_VALGRIND
+#if defined(CHECK_WITH_VALGRIND) || defined(BR916_STOPGAP_FIX)
 	  case _vpiFromThr:
 	    return _vpi_at_A;
 #endif

vvp/vpi_const.cc

@@ -51,7 +51,7 @@ static int string_get(int code, vpiHandle ref)
           case vpiAutomatic:
 	      return 0;
 
-#ifdef CHECK_WITH_VALGRIND
+#if defined(CHECK_WITH_VALGRIND) || defined(BR916_STOPGAP_FIX)
           case _vpiFromThr:
 	      return _vpiNoThr;
 #endif
@@ -363,7 +363,7 @@ static int binary_get(int code, vpiHandle ref)
           case vpiAutomatic:
 	    return 0;
 
-#ifdef CHECK_WITH_VALGRIND
+#if defined(CHECK_WITH_VALGRIND) || defined(BR916_STOPGAP_FIX)
           case _vpiFromThr:
 	      return _vpiNoThr;
 #endif
@@ -564,7 +564,7 @@ static int dec_get(int code, vpiHandle ref)
           case vpiAutomatic:
 	    return 0;
 
-#ifdef CHECK_WITH_VALGRIND
+#if defined(CHECK_WITH_VALGRIND) || defined(BR916_STOPGAP_FIX)
           case _vpiFromThr:
 	      return _vpiNoThr;
 #endif
@@ -675,7 +675,7 @@ static int real_get(int code, vpiHandle ref)
           case vpiAutomatic:
 	    return 0;
 
-#ifdef CHECK_WITH_VALGRIND
+#if defined(CHECK_WITH_VALGRIND) || defined(BR916_STOPGAP_FIX)
           case _vpiFromThr:
 	      return _vpiNoThr;
 #endif

vvp/vpi_priv.h

@@ -40,7 +40,7 @@
 /*
  * Private VPI properties that are only used in the cleanup code.
  */
-#ifdef CHECK_WITH_VALGRIND
+#if defined(CHECK_WITH_VALGRIND) && !defined(BR916_STOPGAP_FIX)
 #define _vpiFromThr 0x1000001
 #   define _vpiNoThr  0
 #   define _vpiVThr   1

vvp/vpi_signal.cc

@@ -557,6 +557,11 @@ static int signal_get(int code, vpiHandle ref)
           case vpiAutomatic:
             return (int) vpip_scope(rfp)->is_automatic;
 
+#ifdef BR916_STOPGAP_FIX
+	  case _vpiFromThr:
+	    return _vpiNoThr;
+#endif
+
 	  case _vpiNexusId:
 	    if (rfp->msb == rfp->lsb)
 		  return (int) (unsigned long) rfp->node;
@@ -1081,7 +1086,7 @@ static int PV_get(int code, vpiHandle ref)
         case vpiAutomatic:
             return vpi_get(vpiAutomatic, rfp->parent);
 
-#ifdef CHECK_WITH_VALGRIND
+#if defined(CHECK_WITH_VALGRIND) || defined(BR916_STOPGAP_FIX)
         case _vpiFromThr:
             return _vpi_at_PV;
 #endif

vvp/vpi_vthr_vector.cc

@@ -93,7 +93,7 @@ static int vthr_vec_get(int code, vpiHandle ref)
 	  case vpiSize:
 	    return rfp->wid;
 
-#ifdef CHECK_WITH_VALGRIND
+#if defined(CHECK_WITH_VALGRIND) || defined(BR916_STOPGAP_FIX)
 	  case _vpiFromThr:
 	    return _vpiVThr;
 #endif
@@ -504,7 +504,7 @@ static int vthr_word_get(int code, vpiHandle ref)
 	  case vpiConstType:
 	    return rfp->subtype;
 
-#ifdef CHECK_WITH_VALGRIND
+#if defined(CHECK_WITH_VALGRIND) || defined(BR916_STOPGAP_FIX)
 	  case _vpiFromThr:
 	    return _vpiWord;
 #endif