[okl4-developer] OKL4 v2.1: Support of ARM Thumb instructionset

[Geoffrey Lee]

On Mon, Jun 30, 2008 at 11:15:17AM +0200, Frank Kaiser wrote:
> Hi, Geoffrey
> 
> But I think it's not currently use, since I do not find any reference to
> a relevant GNU compiler option concerning THUMB mode in the scripts
> belonging to the build system (for instance in a Sconscript file of an
> IGUANA task).


Your observation is correct, we don't current compile Iguana in THUMB mode.  
To compile in THUMB mode you can change the C compiler flags to compile 
code in THUMB mode.

> 
> Regards
> Frank

	-gl

> > -----Original Message-----
> > From: Geoffrey Lee [mailto:glee at ok-labs.com]
> > Sent: Tuesday, June 24, 2008 12:34 PM
> > To: Frank Kaiser
> > Cc: developer at okl4.org
> > Subject: Re: [okl4-developer] OKL4 v2.1: Support of ARM Thumb
> instructionset
> > 
> > I asked the kernel guys, they told me the main reason is you cannot
> have
> > inline assembly for ARM mode when compiling for thumb.  As well,
> > generally ARM code is a bit faster than thumb.
> > 
> > Having said that, we do support running userland in thumb mode.
> > 
> > 	-gl
> 

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