From c50e0e21a06ec2b1f44f95e6842814ac0bc310a6 Mon Sep 17 00:00:00 2001
From: =?UTF-8?q?Niels=20M=C3=B6ller?= <nisse@lysator.liu.se>
Date: Wed, 22 Nov 2023 10:41:27 +0100
Subject: [PATCH] Add hw decode of immediate mullo.

---
 hw/cpu/lib/instr_decode.v | 11 ++++++++++-
 1 file changed, 10 insertions(+), 1 deletion(-)

diff --git a/hw/cpu/lib/instr_decode.v b/hw/cpu/lib/instr_decode.v
index 4d41dc5..7778734 100644
--- a/hw/cpu/lib/instr_decode.v
+++ b/hw/cpu/lib/instr_decode.v
@@ -336,7 +336,16 @@ module instr_decode (input [15:0]      instr,
 	   imm_data = uimm;
 	   imm_enable = 1;
 	end
-	/* Reserved op codes, 1011 1...,  another 4 immediate instructions? */
+	/* Immediate mullo */
+	'b1011_100?_????_????: begin
+	   mul_enable = 1;
+	   mul_op = `OP_MUL_LOW;
+	   dst_write_enable = 1;
+	   src_neg = instr[8];
+	   imm_data = uimm;
+	   imm_enable = 1;
+	end
+	/* Reserved op codes,  another 3 immediate instructions? */
 	/* Immediate tst */
 	'b1100_000?_????_????: begin
 	   alu_enable = 1;
-- 
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