From 6bae7c25c43e65bdb01688db642b21a61733fb86 Mon Sep 17 00:00:00 2001
From: Tim Edwards <tim@opencircuitdesign.com>
Date: Wed, 25 Mar 2020 09:29:16 -0400
Subject: [PATCH] Enhanced the "lef write -hide" command option to check for
 metal wide spacing rules; should result in LEF views that can import back
 into magic without DRC errors.

---
 drc/DRCtech.c  | 59 ++++++++++++++++++++++++++++++++++++++++++++++++++
 lef/lefWrite.c | 22 ++++++++++++++-----
 2 files changed, 75 insertions(+), 6 deletions(-)

diff --git a/drc/DRCtech.c b/drc/DRCtech.c
index 19a906dc..8cde7197 100644
--- a/drc/DRCtech.c
+++ b/drc/DRCtech.c
@@ -4031,3 +4031,62 @@ DRCGetDefaultLayerSurround(ttype1, ttype2)
     }
     return layerSurround;
 }
+
+/*
+ *-----------------------------------------------------------------------------
+ *  DRCGetDefaultLayerWideSpacing ---
+ *
+ *	Determine a default layer-to-self wide-layer spacing rule from
+ *	the DRC width rules of a layer.
+ *
+ * Results:
+ *	The minimum spacing between the specified magic layer type and
+ *	itself, where one of the shapes has width greater than "twidth".
+ *	The result value is in magic internal units.
+ *
+ * Side effects:
+ *	None.
+ *
+ *-----------------------------------------------------------------------------
+ */
+
+int
+DRCGetDefaultWideLayerSpacing(ttype, twidth)
+    TileType ttype;
+    int twidth;
+{
+    int routeSpacing = 0;
+    DRCCookie *cptr;
+    TileTypeBitMask *set;
+    bool widerule = FALSE;
+
+    for (cptr = DRCCurStyle->DRCRulesTbl[ttype][TT_SPACE]; cptr != (DRCCookie *) NULL;
+	cptr = cptr->drcc_next)
+    {
+	if (cptr->drcc_flags & DRC_TRIGGER)		/* Widespacing rule */
+	{
+	    widerule = TRUE;
+	    if (cptr->drcc_dist > twidth)   /* Check against rule width */
+		return routeSpacing;
+	}
+	if (widerule && ((cptr->drcc_flags & DRC_REVERSE) == 0))    /* FORWARD only */
+	{
+	    set = &cptr->drcc_mask;
+	    if (!TTMaskHasType(set, ttype))
+	        if (PlaneMaskHasPlane(DBTypePlaneMaskTbl[ttype], cptr->drcc_plane) &&
+			(cptr->drcc_dist == cptr->drcc_cdist))
+		{
+		    routeSpacing = cptr->drcc_dist;
+		    /* Diagnostic */
+		    /*
+		    TxPrintf("DRC: Layer %s has wide spacing %d to layer %s width %d\n",
+			DBTypeLongNameTbl[ttype1], routeSpacing,
+			DBTypeLongNameTbl[ttype2], twidth);
+		    */
+		}
+	}
+	if (!(cptr->drcc_flags & DRC_TRIGGER)) widerule = FALSE;
+    }
+    return routeSpacing;
+}
+
diff --git a/lef/lefWrite.c b/lef/lefWrite.c
index 4391d727..93fe30de 100644
--- a/lef/lefWrite.c
+++ b/lef/lefWrite.c
@@ -1103,15 +1103,25 @@ lefWriteMacro(def, f, scale, hide)
 
 	for (thislll = lll; thislll; thislll = thislll->lll_next)
 	{
-	    int lspace;
+	    int lspacex, lspacey, lwidth;
 
 	    lab = thislll->lll_label;
 
-	    lspace = DRCGetDefaultLayerSpacing(lab->lab_type, lab->lab_type);
-	    thislll->lll_area.r_xbot -= lspace;
-	    thislll->lll_area.r_ybot -= lspace;
-	    thislll->lll_area.r_xtop += lspace;
-	    thislll->lll_area.r_ytop += lspace;
+	    /* Look for wide spacing rules.  If there are no wide spacing   */
+	    /* rules, then fall back on the default spacing rule.	    */
+	    lwidth = thislll->lll_area.r_xtop - thislll->lll_area.r_xbot;
+	    lspacex = DRCGetDefaultWideLayerSpacing(lab->lab_type, lwidth);
+	    if (lspacex == 0)
+		lspacex = DRCGetDefaultLayerSpacing(lab->lab_type, lab->lab_type);
+	    lwidth = thislll->lll_area.r_ytop - thislll->lll_area.r_ybot;
+	    lspacey = DRCGetDefaultWideLayerSpacing(lab->lab_type, lwidth);
+	    if (lspacey == 0)
+		lspacey = DRCGetDefaultLayerSpacing(lab->lab_type, lab->lab_type);
+
+	    thislll->lll_area.r_xbot -= lspacex;
+	    thislll->lll_area.r_ybot -= lspacey;
+	    thislll->lll_area.r_xtop += lspacex;
+	    thislll->lll_area.r_ytop += lspacey;
 	    DBErase(lc.lefYank, &thislll->lll_area, lab->lab_type);
 
 	    freeMagic(thislll);