Unused binning models are removed.

Flag 'nf', when given on the x lines, is
recognized.
Tested with TSMC, Skywater, and X-Fab model
files.

src/frontend/inp.c

@@ -2452,9 +2452,10 @@ static void rem_unused_mos_models(struct card* deck) {
     }
     for (tmpc = deck; tmpc; tmpc = tmpc->nextcard) {
         char* curr_line = tmpc->line;
-        /* We only look for MOS devices and extract W and L */
+        /* We only look for MOS devices and extract W, L, nf, and wnflag */
         if (*curr_line == 'm') {
-            float w = 0., l = 0.;
+            float w = 0., l = 0., nf = 1., wnf = 1.;
+            int wnflag = 0;
             char* wstr = strstr(curr_line, " w=");
             if (wstr) {
                 int err;
@@ -2475,6 +2476,36 @@ static void rem_unused_mos_models(struct card* deck) {
                     continue;
                 }
             }
+            char* nfstr = strstr(curr_line, " nf=");
+            if (nfstr) {
+                int err;
+                nfstr = nfstr + 4;
+                nfstr = skip_ws(nfstr);
+                nf = (float)INPevaluate(&nfstr, &err, 0);
+                if (err) {
+                    continue;
+                }
+            }
+            char* wnstr = strstr(curr_line, " wnflag=");
+            if (wnstr) {
+                int err;
+                wnstr = wnstr + 8;
+                wnstr = skip_ws(wnstr);
+                wnf = (float)INPevaluate(&wnstr, &err, 0);
+                if (err) {
+                    continue;
+                }
+            }
+            if (!cp_getvar("wnflag", CP_NUM, &wnflag, 0)) {
+                if (newcompat.spe || newcompat.hs)
+                    wnflag = 1;
+                else
+                    wnflag = 0;
+            }
+
+            nf = wnflag * wnf > 0.5f ? nf : 1.f;
+            w = w / nf;
+
             /* what is the device's model name? */
             char* mname = nexttok(curr_line);
             int nonodes = 4; /* FIXME: this is a hack! How to really detect the number of nodes? */

src/frontend/inpcom.c

@@ -617,13 +617,32 @@ static void print_compat_mode(void) {
 }
 
 
-/* We check x lines for w= and l= and fill in their values.
-   To be used when expanding subcircuits with binned model cards. */
+/* We check x lines for nf=, w= and l= and fill in their values.
+   To be used when expanding subcircuits with binned model cards. 
+   
+   In subckt.c, function doit(), lines 621ff. the unsused models
+   are filtered out. 'nf' given on an x line (subcircuit invocation)
+   is aknowledged. The option 'wnflag', if set to 0 in .spiceinit,
+   will set 'nf' to 1 and thus suppress its usage.
+   
+   In inp.c, function rem_unused_mos_models, another trial to removing
+   unused MOS models is given, this time on the expanded m lines and
+   its models.*/
 void inp_get_w_l_x(struct card* card) {
+    int wnflag;
+    if (!cp_getvar("wnflag", CP_NUM, &wnflag, 0)) {
+        if (newcompat.spe || newcompat.hs)
+            wnflag = 1;
+        else
+            wnflag = 0;
+    }
     for (; card; card = card->nextcard) {
         char* curr_line = card->line;
         int skip_control = 0;
-        char* w = NULL, * l = NULL;
+        char* w = NULL, * l = NULL, * nf = NULL;
+
+        card->w = card->l = 0;
+        card->nf = 1.;
 
         /* exclude any command inside .control ... .endc */
         if (ciprefix(".control", curr_line)) {
@@ -639,7 +658,6 @@ void inp_get_w_l_x(struct card* card) {
         }
         /* only subcircuit invocations */
         if (*curr_line != 'x' && !newcompat.hs && !newcompat.spe) {
-            card->w = card->l = 0;
             continue;
         }
 
@@ -649,30 +667,43 @@ void inp_get_w_l_x(struct card* card) {
             w = w + 3;
             card->w = (float)INPevaluate(&w, &err, 0);
             if(err) { 
-                card->w = card->l = 0;
+                card->w = 0;
                 continue;
-           }
+            }
         }
         else {
             card->w = card->l = 0;
             continue;
         }
 
-
         l = strstr(curr_line, " l=");
         if (l) {
             int err;
             l = l + 3;
             card->l = (float)INPevaluate(&l, &err, 0);
             if(err) { 
-                card->w = card->l = 0;
+                card->l = 0;
                 continue;
-           }
+            }
         }
         else {
             card->w = card->l = 0;
             continue;
-        }  
+        }
+        nf = strstr(curr_line, " nf=");
+        if (nf) {
+            int err;
+            nf = nf + 4;
+            card->nf = (float)INPevaluate(&nf, &err, 0);
+            if (err) {
+                card->w = card->l = 0;
+                card->nf = 1.;
+                continue;
+            }
+        }
+        else {
+            continue;
+        }
     }
 }
 

src/frontend/subckt.c

@@ -698,7 +698,9 @@ doit(struct card *deck, wordlist *modnames) {
                             }
 
                             float csl = (float)scale * c->l;
-                            float csw = (float)scale * c->w;
+                            /* scale by nf */
+                            float csw = (float)scale * c->w / c->nf;
+                            /*fprintf(stdout, "Debug: nf = %f\n", c->nf);*/
                             if (csl >= flmin && csl < flmax && csw >= fwmin && csw < fwmax) {
                                 /* use the current .model card */
                                 prev = su_deck;
@@ -823,6 +825,7 @@ struct card * inp_deckcopy(struct card *deck) {
         d->linenum = deck->linenum;
         d->w = deck->w;
         d->l = deck->l;
+        d->nf = deck->nf;
         d->line = copy(deck->line);
         if (deck->error)
             d->error = copy(deck->error);
@@ -867,6 +870,7 @@ struct card *inp_deckcopy_oc(struct card * deck)
         }
         d->w = deck->w;
         d->l = deck->l;
+        d->nf = deck->nf;
         d->linenum_orig = deck->linenum;
         d->linenum = i++;
         d->line = copy(deck->line);
@@ -923,6 +927,7 @@ struct card* inp_deckcopy_ln(struct card* deck)
         }
         d->w = deck->w;
         d->l = deck->l;
+        d->nf = deck->nf;
         d->linenum_orig = deck->linenum_orig;
         d->linenum = deck->linenum;
         d->line = copy(deck->line);

src/include/ngspice/inpdefs.h

@@ -84,6 +84,7 @@ struct card {
     struct nscope *level;
     float w;
     float l;
+    float nf;
 };
 
 /* structure used to save models in after they are read during pass 1 */