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Re: ARMv5, ARMv6 & ARMv7 (Programs for the Raspberry Pi)

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In message <mpro.m2qpgu015g74w01k8.news@stevefryatt.org.uk>
          Steve Fryatt <news@stevefryatt.org.uk> wrote:

> On 19 Apr, Chris Evans wrote in message
>     <ant19150372bpErr@client.cjemicros.co.uk>:

>> p.s. I was told how to patch !Prophet for the BeagleBoard (Can't find the
>> details at present) IIRC it involved removing a ^ from towards the end of
>> a load or store assembler instruction. Is that to do with unaligned memory
>> access.

> Either you or your informant is confused, as the ^ was used to preserve
> flags on multiple loads and stores.  It stopped working on the Iyonix, so
> what you're describing above would have been done to make Prophet 32-bit
> friendly.  Beagleboard compatibility involves removing unaligned loads and
> stores, which is something completely different.

Correct in principle, but I have seen cases similar to the one 
described by Chris in practice. This happens because some of the 
supposedly 32-bit-unsafe instructions continued to work happily on the 
Iyonix, so programmers could get away with missing some of them.

The switch to the BeagleBoard finally uncovers 32-bit conversion 
glitches that went unnoticed before, and therefore, it can happen that 
"^" or "S" modifiers have to be removed from instructions to make a 
program that works fine on the Iyonix work on the BeagleBoard as well.

-- 
Martin
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Martin Wuerthner         MW Software      http://www.mw-software.com/
        RISC OS Software for Design, Printing and Publishing
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ARMv5, ARMv6 & ARMv7 (Programs for the Raspberry Pi) Chris Evans <chris@cjemicros.co.uk> - 2012-04-19 13:05 +0100
  Re: ARMv5, ARMv6 & ARMv7 (Programs for the Raspberry Pi) Martin Bazley <martin.bazley@blueyonder.co.uk> - 2012-04-19 14:15 +0100
    Re: ARMv5, ARMv6 & ARMv7 (Programs for the Raspberry Pi) Chris Evans <chris@cjemicros.co.uk> - 2012-04-19 16:10 +0100
      Re: ARMv5, ARMv6 & ARMv7 (Programs for the Raspberry Pi) Rick Murray <heyrickmail-usenet@yahoo.co.uk> - 2012-04-19 18:41 +0200
      Re: ARMv5, ARMv6 & ARMv7 (Programs for the Raspberry Pi) Steve Fryatt <news@stevefryatt.org.uk> - 2012-04-19 19:46 +0100
        Re: ARMv5, ARMv6 & ARMv7 (Programs for the Raspberry Pi) Martin Wuerthner <spamtrap@mw-software.com> - 2012-04-19 21:24 +0200
  Re: ARMv5, ARMv6 & ARMv7 (Programs for the Raspberry Pi) Rick Murray <heyrickmail-usenet@yahoo.co.uk> - 2012-04-19 18:32 +0200
  Re: ARMv5, ARMv6 & ARMv7 (Programs for the Raspberry Pi) chrisbazley@bigfoot.com - 2012-04-29 06:37 -0700
    Re: ARMv5, ARMv6 & ARMv7 (Programs for the Raspberry Pi) Martin Bazley <martin.bazley@blueyonder.co.uk> - 2012-04-29 15:47 +0100
    Re: ARMv5, ARMv6 & ARMv7 (Programs for the Raspberry Pi) Gerph <gerph@gerph.org> - 2012-04-29 07:39 -0700
    Re: ARMv5, ARMv6 & ARMv7 (Programs for the Raspberry Pi) druck <news@druck.org.uk> - 2012-04-29 19:30 +0100
    Re: ARMv5, ARMv6 & ARMv7 (Programs for the Raspberry Pi) Rick Murray <heyrickmail-usenet@yahoo.co.uk> - 2012-04-30 06:16 +0200
      Re: ARMv5, ARMv6 & ARMv7 (Programs for the Raspberry Pi) druck <news@druck.org.uk> - 2012-04-30 22:47 +0100
      Re: ARMv5, ARMv6 & ARMv7 (Programs for the Raspberry Pi) Gerph <gerph@gerph.org> - 2012-04-30 15:30 -0700
        Re: ARMv5, ARMv6 & ARMv7 (Programs for the Raspberry Pi) Rick Murray <heyrickmail-usenet@yahoo.co.uk> - 2012-05-02 19:26 +0200
          Re: ARMv5, ARMv6 & ARMv7 (Programs for the Raspberry Pi) Gavin Wraith <gavin@wra1th.plus.com> - 2012-05-02 21:02 +0100
          Re: ARMv5, ARMv6 & ARMv7 (Programs for the Raspberry Pi) druck <news@druck.org.uk> - 2012-05-02 22:33 +0100
            Re: ARMv5, ARMv6 & ARMv7 (Programs for the Raspberry Pi) cferris@freeRemoveuk.com.invalid - 2012-05-02 23:37 +0100
              Re: ARMv5, ARMv6 & ARMv7 (Programs for the Raspberry Pi) Rick Murray <heyrickmail-usenet@yahoo.co.uk> - 2012-05-03 06:25 +0200
              Re: ARMv5, ARMv6 & ARMv7 (Programs for the Raspberry Pi) trevj <trevj@cwazy.co.uk> - 2012-05-03 13:01 -0700
          Re: ARMv5, ARMv6 & ARMv7 (Programs for the Raspberry Pi) Rick Murray <heyrickmail-usenet@yahoo.co.uk> - 2012-05-04 06:30 +0200
            Re: ARMv5, ARMv6 & ARMv7 (Programs for the Raspberry Pi) Martin Wuerthner <spamtrap@mw-software.com> - 2012-05-04 11:55 +0200
              Re: ARMv5, ARMv6 & ARMv7 (Programs for the Raspberry Pi) Matthew Phillips <spam2011m@yahoo.co.uk> - 2012-05-04 22:39 +0100
            Re: ARMv5, ARMv6 & ARMv7 (Programs for the Raspberry Pi) Rick Murray <heyrickmail-usenet@yahoo.co.uk> - 2012-05-05 17:58 +0200
              Re: ARMv5, ARMv6 & ARMv7 (Programs for the Raspberry Pi) Theo Markettos <theom+news@chiark.greenend.org.uk> - 2012-05-05 17:22 +0100
        Re: ARMv5, ARMv6 & ARMv7 (Programs for the Raspberry Pi) Simon <simon.willcocks@t-online.de> - 2012-05-04 04:24 -0700
      Re: ARMv5, ARMv6 & ARMv7 (Programs for the Raspberry Pi) Theo Markettos <theom+news@chiark.greenend.org.uk> - 2012-05-01 21:33 +0100
        Re: ARMv5, ARMv6 & ARMv7 (Programs for the Raspberry Pi) Gerph <gerph@gerph.org> - 2012-05-01 17:06 -0700
        Re: ARMv5, ARMv6 & ARMv7 (Programs for the Raspberry Pi) Rick Murray <heyrickmail-usenet@yahoo.co.uk> - 2012-05-02 19:02 +0200

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