From 2a7bd0bf373f264c3e8878fba93e4df7aa5f4af7 Mon Sep 17 00:00:00 2001
From: Duncan Smith
Date: Sat, 26 Jun 2010 14:28:14 -0700
Subject: Completed CP macro-instruction

---
 alu.asm | 12 ++++++++++--
 1 file changed, 10 insertions(+), 2 deletions(-)

(limited to 'alu.asm')

diff --git a/alu.asm b/alu.asm
index 3dfa096..cc81491 100644
--- a/alu.asm
+++ b/alu.asm
@@ -54,8 +54,8 @@ alu_sub:
 	;; sets flags
 
 	;; XXX use lea and then d(an) if you have a spare register.
-	;; preserve operands for flagging
 
+	;; preserve operands for flagging
 	move.b	d0,(f_tmp_src_b-flag_storage)(a3)
 	move.b	d1,(f_tmp_dst_b-flag_storage)(a3)
 	move.b	#1,(f_tmp_byte-flag_storage)(a3)
@@ -78,5 +78,13 @@ alu_or:
 	rts
 
 alu_cp:
-	;; XXX do this
+	;; Same as SUB but the macro that calls this doesn't save the
+	;; result.
+	move.b	d0,(f_tmp_src_b-flag_storage)(a3)
+	move.b	d1,(f_tmp_dst_b-flag_storage)(a3)
+	move.b	#1,(f_tmp_byte-flag_storage)(a3)
+	andi.b	#%00000010,(flag_valid-flag_storage)(a3)
+	move.b	#%00000010,(flag_byte-flag_storage)(a3)
+	sub	d0,d1
+	move	sr,(f_host_sr-flag_storage)(a3)
 	rts
-- 
cgit v1.2.3