diff --git a/src/actions.c b/src/actions.c
index 0845c460..061b85b1 100644
--- a/src/actions.c
+++ b/src/actions.c
@@ -877,8 +877,6 @@ int place_symbol(int pos, const char *symbol_name, double x, double y, short rot
   xctx->instances++; /* must be updated before calling symbol_bbox() */
 
 
-  if(xctx->prep_hash_inst) hash_inst(XINSERT, n); /* no need to rehash, add item */
-  /* xctx->prep_hash_inst=0; */
 
 
   /* force these vars to 0 to trigger a prepare_netlist_structs(0) needed by symbol_bbox->translate
@@ -887,6 +885,8 @@ int place_symbol(int pos, const char *symbol_name, double x, double y, short rot
   xctx->prep_hi_structs=0;
   symbol_bbox(n, &xctx->inst[n].x1, &xctx->inst[n].y1,
                     &xctx->inst[n].x2, &xctx->inst[n].y2);
+  if(xctx->prep_hash_inst) hash_inst(XINSERT, n); /* no need to rehash, add item */
+  /* xctx->prep_hash_inst=0; */
   if(draw_sym & 3) bbox(ADD, xctx->inst[n].x1, xctx->inst[n].y1, xctx->inst[n].x2, xctx->inst[n].y2);
   set_modify(1);
   if(draw_sym&1) {
diff --git a/src/hilight.c b/src/hilight.c
index a02e7d05..3af9731d 100644
--- a/src/hilight.c
+++ b/src/hilight.c
@@ -898,31 +898,32 @@ void print_stack(int  *stack, int sp)
 int eval_logic_expr(int inst, int output)
 {
   int stack[STACKMAX];
-  int i, sp = 0;
-  char *saveptr = NULL;
-  char *ptr1;
-  char *ptr2;
-  char *arg;
+  int pos = 0, i, sp = 0;
+  char *str;
   int res = 0;
 
-  my_strdup(827, &saveptr, xctx->simdata.inst[inst].pin[output].function);
-  dbg(1, "eval_logic_expr(): inst=%d pin=%d function=%s\n", inst, output, saveptr ? saveptr : "NULL");
-  if(!saveptr) return 2; /* no logic function defined, return LOGIC_X */
-  ptr2 = saveptr;
-  while( (arg = my_strtok_r(ptr2, " ", &ptr1)) ) {
-    ptr2 = NULL;
-    if(arg[0] == 'd') { /* duplicate top element*/
+  str = xctx->simdata.inst[inst].pin[output].function;
+  dbg(1, "eval_logic_expr(): inst=%d pin=%d function=%s\n", inst, output, str ? str : "NULL");
+  if(!str) return 2; /* no logic function defined, return LOGIC_X */
+  while(str[pos]) {
+    if(str[pos] == 'd') { /* duplicate top element*/
       if(sp > 0 && sp < STACKMAX) {
         stack[sp] = stack[sp - 1];
         sp++;
       }
-    } else if(arg[0] == '~') { /* negation operator */
+    } else if(str[pos] == 'x') { /* exchange top 2 operands */
+      if(sp > 1) {
+         int tmp = stack[sp - 2];
+         stack[sp - 2] =  stack[sp - 1];
+         stack[sp - 1] = tmp;
+      }
+    } else if(str[pos] == '~') { /* negation operator */
       if(sp > 0) {
         sp--;
         if(stack[sp] != 2) stack[sp] = !stack[sp];
         ++sp;
       }
-    } else if(arg[0] == '|') { /* or operator */
+    } else if(str[pos] == '|') { /* or operator */
       if(sp > 1) {
         res = 0;
         for(i = sp - 2; i < sp; i++) {
@@ -936,7 +937,7 @@ int eval_logic_expr(int inst, int output)
         stack[sp - 2] = res;
         sp--;
       }
-    } else if(arg[0] == '&') { /* and operator */
+    } else if(str[pos] == '&') { /* and operator */
       if(sp > 1) {
         res = 1;
         for(i = sp - 2; i < sp; i++) {
@@ -950,7 +951,7 @@ int eval_logic_expr(int inst, int output)
         stack[sp - 2] = res;
         sp--;
       }
-    } else if(arg[0] == '^') { /* xor operator */
+    } else if(str[pos] == '^') { /* xor operator */
       if(sp > 1) {
         res = 0;
         for(i = sp - 2; i < sp; i++) {
@@ -965,22 +966,25 @@ int eval_logic_expr(int inst, int output)
         stack[sp - 2] = res;
         sp--;
       }
-    } else if(arg[0] == 'L') { /* logic low (0) */
+    } else if(str[pos] == 'L') { /* logic low (0) */
       if(sp < STACKMAX) {
         stack[sp++] = 0;
       }
-    } else if(arg[0] == 'H') { /* logic high (1) */
+    } else if(str[pos] == 'H') { /* logic high (1) */
       if(sp < STACKMAX) {
         stack[sp++] = 1;
       }
-    } else if(isdigit(arg[0])) {
+    } else if(isdigit(str[pos])) {
       if(sp < STACKMAX) {
-        stack[sp++] = get_logic_value(inst, atoi(arg));
+        char *num = str + pos;
+        while(isdigit(str[++pos])) ;
+        pos--; /* push back last non digit character */
+        stack[sp++] = get_logic_value(inst, atoi(num));
       }
       else dbg(0, "eval_logic_expr(): stack overflow!\n");
     }
+    pos++;
   }
-  my_free(1218, &saveptr);
   dbg(1, "eval_logic_expr(): inst %d output %d, returning %d\n", inst, output, stack[0]);
   return stack[0];
 }
diff --git a/xschem_library/rom8k/lvnand2.sym b/xschem_library/rom8k/lvnand2.sym
index 59bf231c..819869d1 100644
--- a/xschem_library/rom8k/lvnand2.sym
+++ b/xschem_library/rom8k/lvnand2.sym
@@ -1,5 +1,7 @@
-v {xschem version=2.9.5_RC6 file_version=1.1}
-G {type=subcircuit
+v {xschem version=2.9.9 file_version=1.2 }
+G {}
+K {type=subcircuit
+function0="1 2 & ~"
 vhdl_stop=true
 verilog_stop=true
 format="@name @pinlist @VCCPIN @VSSPIN @symname wna=@wna lna=@lna wpa=@wpa lpa=@lpa wnb=@wnb lnb=@lnb wpb=@wpb lpb=@lpb m=@m"
@@ -38,8 +40,8 @@ L 4 22.5 -22.5 30 -15 {}
 L 4 30 -15 33.75 -7.5 {}
 L 4 33.75 -7.5 35 0 {}
 B 5 57.5 -2.5 62.5 2.5 {name=y dir=out verilog_type=wire}
-B 5 -42.5 -22.5 -37.5 -17.5 {name=a dir=in}
-B 5 -42.5 17.5 -37.5 22.5 {name=b dir=in}
+B 5 -42.5 -22.5 -37.5 -17.5 {name=a dir=in goto=0}
+B 5 -42.5 17.5 -37.5 22.5 {name=b dir=in goto=0}
 T {na:@wna\\/@lna
 nb:@wnb\\/@lnb} -35 65 2 1 0.2 0.2 {}
 T {pa:@wpa\\/@lpa
diff --git a/xschem_library/rom8k/lvnot.sym b/xschem_library/rom8k/lvnot.sym
index 9f394630..bd5c6ff7 100644
--- a/xschem_library/rom8k/lvnot.sym
+++ b/xschem_library/rom8k/lvnot.sym
@@ -1,5 +1,7 @@
-v {xschem version=2.9.7 file_version=1.2}
-G {type=subcircuit
+v {xschem version=2.9.9 file_version=1.2 }
+G {}
+K {type=subcircuit
+function0="1 ~"
 vhdl_stop=true
 verilog_stop=true
 format="@name @pinlist @VCCPIN @VSSPIN @symname wn=@wn lln=@lln wp=@wp lp=@lp m=@m"
@@ -26,7 +28,7 @@ L 4 18.75 5 23.75 5 {}
 L 4 16.25 2.5 18.75 5 {}
 L 4 26.25 0 40 0 {}
 B 5 37.5 -2.5 42.5 2.5 {name=y dir=out verilog_type=wire}
-B 5 -42.5 -2.5 -37.5 2.5 {name=a dir=in}
+B 5 -42.5 -2.5 -37.5 2.5 {name=a dir=in goto=0}
 T {n:@wn\\/@lln} -35 35 2 1 0.2 0.2 {}
 T {p:@wp\\/@lp} -35 -22.5 2 1 0.2 0.2 {}
 T {@name} -26.25 -5 0 0 0.2 0.2 {}