From mboxrd@z Thu Jan  1 00:00:00 1970
X-Spam-Checker-Version: SpamAssassin 3.4.4 (2020-01-24) on inbox.vuxu.org
X-Spam-Level: 
X-Spam-Status: No, score=-0.0 required=5.0 tests=T_SCC_BODY_TEXT_LINE
	autolearn=ham autolearn_force=no version=3.4.4
Received: (qmail 13525 invoked from network); 5 Jul 2023 00:04:10 -0000
Received: from 9front.inri.net (168.235.81.73)
  by inbox.vuxu.org with ESMTPUTF8; 5 Jul 2023 00:04:10 -0000
Received: from duke.felloff.net ([216.126.196.34]) by 9front; Tue Jul  4 20:03:02 -0400 2023
Message-ID: <F3A5ED8754709FED1D5A28F39DAD5AA7@felloff.net>
Date: Wed, 05 Jul 2023 02:02:52 +0200
From: cinap_lenrek@felloff.net
To: 9front@9front.org
In-Reply-To: <19324C57-6024-44E1-9F78-F5564055B6BB@stanleylieber.com>
MIME-Version: 1.0
Content-Type: text/plain; charset="US-ASCII"
Content-Transfer-Encoding: 7bit
List-ID: <9front.9front.org>
List-Help: <http://lists.9front.org>
X-Glyph: ➈
X-Bullshit: STM factory lifecycle firewall-scale optimizer 
Subject: Re: [9front] Re: [9front] reform hjfs file creation broken in current release and after
Reply-To: 9front@9front.org
Precedence: bulk

ok, found it and pushed a fix to 7c.

The problem was the line

uvlong i;
int j;

i = j = -1;

generating:

MOVW $-1, R1			<- !!!!
/* SXTW R1, R1			<- missing */
MOVW R1, j+xxx(SP)
MOV R1, i+xxx(SP)

the SXTW was missing because of an optimisation,
eliding these SXTW's as MOVW generally sign
extends already so the SXTW instruction is
not needed...

but there is an exception!

MOVW with a *CONSTANT* is actually equivalent to
MOVWU and always zero extends! (because you
could'v just used MOV instead if you wanted 64-bit?)

fixed the optimiser handling this special case.

--
cinap