FfData: some refactoring.

- FfData now keeps track of the module and underlying cell, if any (so
  calling emit on FfData created from a cell will replace the existing cell)
- FfData implementation is split off to its own .cc file for faster
  compilation
- the "flip FF data sense by inserting inverters in front and after"
  functionality that zinit uses is moved onto FfData class and beefed up
  to have dffsr support, to support more use cases

1 files changed, 9 insertions, 43 deletions

diff --git a/passes/techmap/zinit.cc b/passes/techmap/zinit.cc
index 8fcc47570..cc208c516 100644
--- a/passes/techmap/zinit.cc
+++ b/passes/techmap/zinit.cc
@@ -25,14 +25,6 @@
 USING_YOSYS_NAMESPACE
 PRIVATE_NAMESPACE_BEGIN
 
-State invert(State s) {
-	switch (s) {
-		case State::S0: return State::S1;
-		case State::S1: return State::S0;
-		default: return s;
-	}
-}
-
 struct ZinitPass : public Pass {
 	ZinitPass() : Pass("zinit", "add inverters so all FF are zero-initialized") { }
 	void help() override
@@ -75,45 +67,19 @@ struct ZinitPass : public Pass {
 					continue;
 
 				FfData ff(&initvals, cell);
-				if (!ff.width)
-					continue;
-
-				// Supporting those would require a new cell type where S has priority over R.
-				if (ff.has_sr)
-					continue;
-
-				Wire *new_q = module->addWire(NEW_ID, ff.width);
 
 				log("FF init value for cell %s (%s): %s = %s\n", log_id(cell), log_id(cell->type),
 						log_signal(ff.sig_q), log_signal(ff.val_init));
 
-				IdString name = cell->name;
-				module->remove(cell);
-				initvals.remove_init(ff.sig_q);
-
-				for (int i = 0; i < ff.width; i++)
-					if (ff.val_init[i] == State::S1)
-					{
-						if (ff.has_clk || ff.has_gclk)
-							ff.sig_d[i] = module->NotGate(NEW_ID, ff.sig_d[i]);
-						if (ff.has_aload)
-							ff.sig_ad[i] = module->NotGate(NEW_ID, ff.sig_ad[i]);
-						if (ff.has_arst)
-							ff.val_arst[i] = invert(ff.val_arst[i]);
-						if (ff.has_srst)
-							ff.val_srst[i] = invert(ff.val_srst[i]);
-						module->addNotGate(NEW_ID, SigSpec(new_q, i), ff.sig_q[i]);
-						ff.val_init[i] = State::S0;
-					}
-					else
-					{
-						module->connect(ff.sig_q[i], SigSpec(new_q, i));
-						if (all_mode)
-							ff.val_init[i] = State::S0;
-					}
-
-				ff.sig_q = new_q;
-				ff.emit(module, name);
+				pool<int> bits;
+				for (int i = 0; i < ff.width; i++) {
+					if (ff.val_init.bits[i] == State::S1)
+						bits.insert(i);
+					else if (ff.val_init.bits[i] != State::S0 && all_mode)
+						ff.val_init.bits[i] = State::S0;
+				}
+				ff.flip_bits(bits);
+				ff.emit();
 			}
 		}
 	}