From abf2a9c9fd43afe25f4488b7aac2026d4a15450a Mon Sep 17 00:00:00 2001
From: Adam Sampson <ats@offog.org>
Date: Mon, 24 Aug 2020 14:02:41 +0100
Subject: [PATCH] Shorten tvbrot's iter loop.

The code is now short enough to run from the registers, which would give
a speed improvement on a real KA.
---
 src/lars/{tvbrot.208 => tvbrot.209} | 9 +++++----
 1 file changed, 5 insertions(+), 4 deletions(-)
 rename src/lars/{tvbrot.208 => tvbrot.209} (95%)

diff --git a/src/lars/tvbrot.208 b/src/lars/tvbrot.209
similarity index 95%
rename from src/lars/tvbrot.208
rename to src/lars/tvbrot.209
index a7db8f72..d3c9f217 100644
--- a/src/lars/tvbrot.208
+++ b/src/lars/tvbrot.209
@@ -123,19 +123,20 @@ xloop:
 	move i,y
 	movei t,maxiter
 
+; This loop would fit in the KA registers, given r/i/a/t as regs 0-3.
 iter:	move a,i
 	fmpr a,a
 	fmpr i,r
 	fsc i,1
 	fmpr r,r
-	move b,r
 	fsbr r,a
-	fadr b,a
-	fsbri b,(4.0)
-	jumpge b,out
+	fsc a,1
+	fadr a,r
 	fadr r,x
 	fadr i,y
+	camge a,[203400,,]		;a (which must be positive) >= 4.0?
 	sojg t,iter
+	jumpn t,out			;Loc 20 - did we exceed iter?
 
 	xct dot				;Draw a dot.
 	setom dots			;At least one dot on this line.