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RE: Re: Silly question about ARM thumb
- From: "Paul D. DeRocco" <pderocco at ix dot netcom dot com>
- To: "eCos Discuss" <ecos-discuss at ecos dot sourceware dot org>
- Date: Wed, 23 Feb 2005 10:06:32 -0800
- Subject: RE: [ECOS] Re: Silly question about ARM thumb
> From: Ian Campbell
>
> is it also the case that on a system with a 32 bit bus that 2
> consecutive thumb instructions can be fetched in a single external
> memory read?
Apparently not. Strangely, the ARM core can automatically detect repeated
accesses to the same or consecutive addresses, for the purpose of optimizing
pipelining, but doesn't use this to optimize instruction fetches. There's
probably a way of using this to make Thumb instruction fetches on a 32-bit
bus more efficient, with a bit of external hardware.
--
Ciao, Paul D. DeRocco
Paul mailto:pderocco@ix.netcom.com
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