From be8ba0937392d0996cdcda3e404c1057de4f9b5e Mon Sep 17 00:00:00 2001
From: Tim Edwards <tim@opencircuitdesign.com>
Date: Wed, 20 Nov 2019 13:36:03 -0500
Subject: [PATCH] Created an additional argument "start" to the "slots"
 operator, which adds an offset value of "start" to both X and Y from the
 lower left corner of the fill area.  This allows the use of the "offset"
 (from the previous git commit) to be declared on different layers without
 creating an exact overlap, as is often required by foundries for fill
 patterns.

---
 cif/CIFgen.c  |  6 +++---
 cif/CIFint.h  |  1 +
 cif/CIFtech.c | 23 +++++++++++++++++++----
 3 files changed, 23 insertions(+), 7 deletions(-)

diff --git a/cif/CIFgen.c b/cif/CIFgen.c
index d2af4afb..6de88309 100644
--- a/cif/CIFgen.c
+++ b/cif/CIFgen.c
@@ -2011,13 +2011,13 @@ cifSlotsFillArea(op, cellDef, plane)
 
 	    cifSlotFunc(&bbox, op, &nUp, &nAcross, &llcut, vertical);
 
-	    cut.r_ybot = llcut.r_ybot;
-	    cut.r_ytop = llcut.r_ytop;
+	    cut.r_ybot = llcut.r_ybot + slots->sl_start;
+	    cut.r_ytop = llcut.r_ytop + slots->sl_start;
 
 	    /* For each contact cut area, check that there is	*/
 	    /* no whitespace					*/
 
-	    offset = 0;
+	    offset = slots->sl_start;
 	    for (i = 0; i < nUp; i++)
 	    {
 		cut.r_xbot = llcut.r_xbot + offset;
diff --git a/cif/CIFint.h b/cif/CIFint.h
index c9280e12..157a3cff 100644
--- a/cif/CIFint.h
+++ b/cif/CIFint.h
@@ -69,6 +69,7 @@ typedef struct slots_data
     int sl_lsize;
     int sl_lsep;
     int sl_offset;
+    int sl_start;
 } SlotsData;
 
 typedef struct cifop
diff --git a/cif/CIFtech.c b/cif/CIFtech.c
index 309b06e0..2040bc7f 100644
--- a/cif/CIFtech.c
+++ b/cif/CIFtech.c
@@ -1327,6 +1327,7 @@ bloatCheck:
 		slots->sl_lsize = 0;
 		slots->sl_lsep = 0;
 		slots->sl_offset = 0;
+		slots->sl_start = 0;
 	    }
 	    if (argc >= 5)
 	    {
@@ -1361,7 +1362,7 @@ bloatCheck:
 		    goto errorReturn;
 		}
 	    }
-	    if (argc == 8)
+	    if (argc >= 8)
 	    {
 		i = atoi(argv[7]);
 		slots->sl_offset = i;
@@ -1371,7 +1372,17 @@ bloatCheck:
 		    goto errorReturn;
 		}
 	    }
-	    if ((argc < 4) || (argc == 6) || (argc > 8))
+	    if (argc == 9)
+	    {
+		i = atoi(argv[8]);
+		slots->sl_start = i;
+		if (i < 0)
+		{
+		    TechError("Slot start must be non-negative.\n");
+		    goto errorReturn;
+		}
+	    }
+	    if ((argc < 4) || (argc == 6) || (argc > 9))
 		goto wrongNumArgs;
 	    break;
     }
@@ -1685,7 +1696,7 @@ CIFTechFinal()
 		{
 		    slots = (SlotsData *)op->co_client;
 
-		    for (j = 0; j < 7; j++)
+		    for (j = 0; j < 8; j++)
 		    {
 			switch (j) {
 			   case 0: bvalue = slots->sl_sborder; break;
@@ -1695,6 +1706,7 @@ CIFTechFinal()
 			   case 4: bvalue = slots->sl_lsize; break;
 			   case 5: bvalue = slots->sl_lsep; break;
 			   case 6: bvalue = slots->sl_offset; break;
+			   case 7: bvalue = slots->sl_start; break;
 			}
 			if (bvalue != 0)
 			{
@@ -2193,7 +2205,7 @@ CIFTechOutputScale(n, d)
 		else if (op->co_opcode == CIFOP_SLOTS)
 		{
 		    slots = (SlotsData *)op->co_client;
-		    for (j = 0; j < 7; j++)
+		    for (j = 0; j < 8; j++)
 		    {
 			switch (j) {
 			    case 0: bptr = &slots->sl_sborder; break;
@@ -2203,6 +2215,7 @@ CIFTechOutputScale(n, d)
 			    case 4: bptr = &slots->sl_lsize; break;
 			    case 5: bptr = &slots->sl_lsep; break;
 			    case 6: bptr = &slots->sl_offset; break;
+			    case 7: bptr = &slots->sl_start; break;
 			}
 			if (*bptr != 0)
 			{
@@ -2319,6 +2332,8 @@ CIFTechOutputScale(n, d)
 			    slots->sl_lsep /= lexpand;
 			if (slots->sl_offset != 0)
 			    slots->sl_offset /= lexpand;
+			if (slots->sl_start != 0)
+			    slots->sl_start /= lexpand;
 			break;
 		    case CIFOP_SQUARES_G:
 			squares = (SquaresData *)op->co_client;