From 8aee80040de0b0812f2aec7ba4059c14407a0567 Mon Sep 17 00:00:00 2001
From: Claire Xenia Wolf <claire@clairexen.net>
Date: Mon, 15 Mar 2021 23:27:55 +0100
Subject: [PATCH] Add default assignments to SB_LUT4

Signed-off-by: Claire Xenia Wolf <claire@clairexen.net>
---
 techlibs/ice40/cells_sim.v | 18 +++++++++++++++++-
 tests/arch/run-test.sh     |  2 +-
 2 files changed, 18 insertions(+), 2 deletions(-)

diff --git a/techlibs/ice40/cells_sim.v b/techlibs/ice40/cells_sim.v
index 7ee809262..2af99269c 100644
--- a/techlibs/ice40/cells_sim.v
+++ b/techlibs/ice40/cells_sim.v
@@ -2,6 +2,16 @@
 `define SB_DFF_REG reg Q = 0
 // `define SB_DFF_REG reg Q
 
+`ifndef NO_ICE40_DEFAULT_ASSIGNMENTS
+`define ICE40_DEFAULT_ASSIGNMENT_V(v) = v
+`define ICE40_DEFAULT_ASSIGNMENT_0 = 1'b0
+`define ICE40_DEFAULT_ASSIGNMENT_1 = 1'b1
+`else
+`define ICE40_DEFAULT_ASSIGNMENT_V(v)
+`define ICE40_DEFAULT_ASSIGNMENT_0
+`define ICE40_DEFAULT_ASSIGNMENT_1
+`endif
+
 // SiliconBlue IO Cells
 
 module SB_IO (
@@ -164,7 +174,13 @@ endmodule
 // SiliconBlue Logic Cells
 
 (* abc9_lut=1, lib_whitebox *)
-module SB_LUT4 (output O, input I0, I1, I2, I3);
+module SB_LUT4 (
+	output O,
+	input I0 `ICE40_DEFAULT_ASSIGNMENT_0,
+	input I1 `ICE40_DEFAULT_ASSIGNMENT_0,
+	input I2 `ICE40_DEFAULT_ASSIGNMENT_0,
+	input I3 `ICE40_DEFAULT_ASSIGNMENT_0
+);
 	parameter [15:0] LUT_INIT = 0;
 	wire [7:0] s3 = I3 ? LUT_INIT[15:8] : LUT_INIT[7:0];
 	wire [3:0] s2 = I2 ?       s3[ 7:4] :       s3[3:0];
diff --git a/tests/arch/run-test.sh b/tests/arch/run-test.sh
index 170078a7f..5d923db56 100755
--- a/tests/arch/run-test.sh
+++ b/tests/arch/run-test.sh
@@ -11,7 +11,7 @@ for arch in ../../techlibs/*; do
 		if [ "${defines[$arch_name]}" ]; then
 			for def in ${defines[$arch_name]}; do
 				echo -n "Test $path -D$def ->"
-				iverilog -t null -I$arch -D$def $path
+				iverilog -t null -I$arch -D$def -DNO_ICE40_DEFAULT_ASSIGNMENTS $path
 				echo " ok"
 			done
 		else
-- 
2.30.2