Corrected the fill generation script to avoid dropping fill outside
the chip area if the chip area is not an exact multiple of the check
step. Also added a density check script for running on final GDS
with fill (the output of the fill generation script).
diff --git a/sky130/Makefile.in b/sky130/Makefile.in
index b4f0bd6..9fabc6c 100644
--- a/sky130/Makefile.in
+++ b/sky130/Makefile.in
@@ -313,6 +313,7 @@
(cd ${MAGICTOP_STAGING_A} ; ln -s ${REV_DIR} current)
cp -rp custom/scripts/seal_ring_generator ${MAGIC_STAGING_A}/.
cp custom/scripts/generate_fill.py ${MAGIC_STAGING_A}/.
+ cp custom/scripts/check_density.py ${MAGIC_STAGING_A}/.
${CPP} ${SKY130A_DEFS} magic/${TECH}.tech > ${MAGIC_STAGING_A}/${SKY130A}.tech
${CPP} ${SKY130A_DEFS} magic/${TECH}gds.tech > ${MAGIC_STAGING_A}/${SKY130A}-GDS.tech
${CPP} ${SKY130A_DEFS} magic/${TECH}.magicrc > ${MAGIC_STAGING_A}/${SKY130A}.magicrc
