From a3b25b4af899b78d7401ec2ea7cd988d6209e226 Mon Sep 17 00:00:00 2001
From: Pepijn de Vos <pepijndevos@gmail.com>
Date: Tue, 3 Dec 2019 15:12:25 +0100
Subject: [PATCH] Use -match-init to not synth contradicting init values

---
 techlibs/gowin/synth_gowin.cc |  2 +-
 tests/arch/gowin/init.ys      | 22 ++++++++++++----------
 2 files changed, 13 insertions(+), 11 deletions(-)

diff --git a/techlibs/gowin/synth_gowin.cc b/techlibs/gowin/synth_gowin.cc
index 49fde540c..6cf058f29 100644
--- a/techlibs/gowin/synth_gowin.cc
+++ b/techlibs/gowin/synth_gowin.cc
@@ -216,7 +216,7 @@ struct SynthGowinPass : public ScriptPass
 		if (check_label("map_ffs"))
 		{
 			run("dffsr2dff");
-			run("dff2dffs");
+			run("dff2dffs -match-init");
 			run("opt_clean");
 			if (!nodffe)
 				run("dff2dffe -direct-match $_DFF_* -direct-match $__DFFS_*");
diff --git a/tests/arch/gowin/init.ys b/tests/arch/gowin/init.ys
index dc8206825..ddc0e4757 100644
--- a/tests/arch/gowin/init.ys
+++ b/tests/arch/gowin/init.ys
@@ -36,7 +36,8 @@ design -load read
 # these should synth to a flop with reset
 chparam -set INIT 1 myDFF myDFFN myDFFE myDFFNE
 
-# these should give a warning
+# async should give a warning
+# sync should synth to a mux
 chparam -set INIT 0 myDFF*S* myDFF*P*
 chparam -set INIT 1 myDFF*R* myDFF*C*
 
@@ -45,28 +46,29 @@ flatten
 synth_gowin -run coarse:
 
 # check the flops mapped as expected
-select -assert-count 0 t:DFF
+select -assert-count 1 t:DFF
 select -assert-count 1 t:DFFC
 select -assert-count 1 t:DFFCE
-select -assert-count 0 t:DFFE
-select -assert-count 0 t:DFFN
+select -assert-count 1 t:DFFE
+select -assert-count 1 t:DFFN
 select -assert-count 1 t:DFFNC
 select -assert-count 1 t:DFFNCE
-select -assert-count 0 t:DFFNE
+select -assert-count 1 t:DFFNE
 select -assert-count 1 t:DFFNP
 select -assert-count 1 t:DFFNPE
-select -assert-count 1 t:DFFNR
-select -assert-count 1 t:DFFNRE
+select -assert-count 0 t:DFFNR
+select -assert-count 0 t:DFFNRE
 select -assert-count 2 t:DFFNS
 select -assert-count 2 t:DFFNSE
 select -assert-count 1 t:DFFP
 select -assert-count 1 t:DFFPE
-select -assert-count 1 t:DFFR
-select -assert-count 1 t:DFFRE
+select -assert-count 0 t:DFFR
+select -assert-count 0 t:DFFRE
 select -assert-count 2 t:DFFS
 select -assert-count 2 t:DFFSE
+select -assert-count 12 t:LUT2
 
 # check the expected leftover init values
 # this would happen if your reset value is not the initial value
 # which would be weird
-select -assert-count 16 a:init
+select -assert-count 8 a:init
-- 
2.30.2