From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from smtp.kernel.org (aws-us-west-2-korg-mail-1.web.codeaurora.org [10.30.226.201]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id 85F012E06EF for ; Wed, 18 Jun 2025 12:59:57 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=10.30.226.201 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1750251597; cv=none; b=rleFi15djGs8z63aJmlNrud+ZKO4uqIt1nDzKPXa9kOFIRfVd5Yn/uL0wrr3eMT2H7zO5Gw75HCmGJQG/bxj10jt8/iJlXN4ecWC4sfQNr+8xrtRRSYZY1WEgHUJzxchz1qgpqObalbyhEVAQeBRqoe2KeYBtD4AfGfmKMlZOWQ= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1750251597; c=relaxed/simple; bh=5AXFoe5XQ1i00S0OUmfW8xC3MZwiS6oqD1yLe+OOyXo=; h=Message-ID:Date:MIME-Version:Subject:To:Cc:References:From: In-Reply-To:Content-Type; b=Uw9ULhrUwWhRqT42I6IOr22IW4ktuNSoTnzWGdWAG9rSY9F5BorbD9YeqIauSzO/VUsOvVQ980MzW56wZmdl00+3eiejSfoId3kgaSAmQagX013nDVq3NS+z6Kpm9VRwGZrQ+MsVF5poxwAR2VNOwk0w3wHzC2ocFf8HQ/hXM+c= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b=WUCbh4oO; arc=none smtp.client-ip=10.30.226.201 Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b="WUCbh4oO" Received: by smtp.kernel.org (Postfix) with ESMTPSA id 36E72C4CEE7; Wed, 18 Jun 2025 12:59:56 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=k20201202; t=1750251597; bh=5AXFoe5XQ1i00S0OUmfW8xC3MZwiS6oqD1yLe+OOyXo=; h=Date:Subject:To:Cc:References:From:In-Reply-To:From; b=WUCbh4oO95vARHoS942+iNQaDnsZAOSStOL/8FdWUOn3f9CFaDOszcoXIHpnpZrVR GrCiCAAvjg7G3GzYae1X0i4kEMKGxB5yf8YW0WAoNFg/Rpo1yiEfn5PTOWBnnC1iwS TQhw9f4qPrm0FkHSb/Sd26e56gtJqfz8AZ4lsvoltUtI52W4+Kh+vrV6anR57FU8vD L0mNEtbuq4dBw+45JPRrf4dktDDGTdVFSC+TxHkGAqhlBBNOskfVucTELR2F+VDG0u 7ofRRdhoU5gLQWS0g3z9Xp07HLNw1tALQNOMjnHqpMwbkYb6CVafOazNCxixzJygCk dcKMiToxvgT4Q== Message-ID: <07736e45-f71e-425a-8fff-3a11957d8353@kernel.org> Date: Wed, 18 Jun 2025 22:59:53 +1000 Precedence: bulk X-Mailing-List: linux-m68k@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 User-Agent: Mozilla Thunderbird Subject: Re: Question on BIGGEST_ALIGNMENT in GCC on NetBSD/m68k To: Geert Uytterhoeven , John Paul Adrian Glaubitz Cc: port-m68k , debian-68k , linux-m68k References: <5d8619dfe4134319b558684209f2b89c5c1447cf.camel@physik.fu-berlin.de> <889f54af-2317-ee51-cea5-47d813683944@linux-m68k.org> <5de0835e46f8c2479668fe5fe98f8e0d230cbfce.camel@physik.fu-berlin.de> <0b09dcea10c9bab4a50b2599ef8ac59b89f09b3e.camel@physik.fu-berlin.de> <8eb87c55-95c2-0c73-4941-6e8732266220@linux-m68k.org> <4c0581c5baccf73e96e53d755e70b57b23ba1da4.camel@physik.fu-berlin.de> <29677f1e81b42c87926875109907485e41587883.camel@physik.fu-berlin.de> <38c670cc-6169-4720-a883-c34df26e1a4f@kernel.org> <6e0e0cf97b77d881b67916889d4b172c5bbdda00.camel@physik.fu-berlin.de> Content-Language: en-US From: Greg Ungerer In-Reply-To: Content-Type: text/plain; charset=UTF-8; format=flowed Content-Transfer-Encoding: 7bit Hi Geert, On 18/6/25 22:54, Geert Uytterhoeven wrote: > Hi Adrian, > > On Wed, 18 Jun 2025 at 14:27, John Paul Adrian Glaubitz > wrote: >> On Wed, 2025-06-18 at 22:21 +1000, Greg Ungerer wrote: >>>> Could you please elaborate this a bit more, please? >>>> >>>> Coldfire is handled as a separate target via TARGET_COLDFIRE in GCC, so we >>>> would certainly be able to toggle the alignment settings independent of >>>> what's done on classic m68k. >>> >>> The net out is that it is the same gcc compiler, m68k-linux-gcc. >>> ColdFire just needs specific code generation via command line switches, >>> like -m5200 (or -m5206e or -m5307 or -mcfv4e, etc). This is the same way >>> you would specify 680x0 level - m68020, -m68030, etc. >> >> Yes, but there is a TARGET_COLDFIRE macro as I mentioned above which could >> be used to trigger which alignment to use by default. I don't see how that >> would complicate things. >> >>> The bulk of the instruction set is the same. Asm code will look totally >>> familiar to anyone who knows m68k :-) One notable difference is that >>> there is a more limited set addressing modes for some instructions. >> >> True, but you won't be able to run any classic m68k binaries on ColdFire >> and the other way around, are you? > > IIIRC if you use a proper subset of the user mode instructions, you > can create binaries that run on both. You might be right on that. If you chose the lowest common denominator of ColdFire code generation, -m5200, then I seem to recall for user space that would just be a subset of traditional 68k. Regards Greg