For now, short $_DFF_[NP]_ from ff_map.v at re-integration

1 files changed, 8 insertions, 0 deletions

diff --git a/passes/techmap/abc9.cc b/passes/techmap/abc9.cc
index f7f2e862a..69b0c1192 100644
--- a/passes/techmap/abc9.cc
+++ b/passes/techmap/abc9.cc
@@ -511,6 +511,7 @@ void abc9_module(RTLIL::Design *design, RTLIL::Module *current_module, std::stri
 
 		// Remove all AND, NOT, and ABC box instances
 		// in preparation for stitching mapped_mod in
+		// Short $_DFF_[NP]_ cells used by ABC (FIXME)
 		dict<IdString, decltype(RTLIL::Cell::parameters)> erased_boxes;
 		for (auto it = module->cells_.begin(); it != module->cells_.end(); ) {
 			RTLIL::Cell* cell = it->second;
@@ -518,6 +519,13 @@ void abc9_module(RTLIL::Design *design, RTLIL::Module *current_module, std::stri
 				it = module->cells_.erase(it);
 				continue;
 			}
+			else if (cell->type.in("$_DFF_N_", "$_DFF_P_")) {
+				SigBit D = cell->getPort("\\D");
+				SigBit Q = cell->getPort("\\Q");
+				module->connect(Q, D);
+				it = module->cells_.erase(it);
+				continue;
+			}
 			RTLIL::Module* box_module = design->module(cell->type);
 			if (box_module && box_module->attributes.count("\\abc_box_id")) {
 				erased_boxes.insert(std::make_pair(it->first, std::move(cell->parameters)));