Re: [ECOS] ARM arch: unknown asm insn "mrc" in v5T_semantics()

[Mark Salter <msalter at redhat dot com>]

>>>>> Heiko Panther writes:

> Mark Salter wrote:
>> In general, I'm pretty uncomfortable with running the stub code in thumb
>> mode. For most ARM CPUs, the cache flushes done in the stub use co-proc
>> insns not available in thumb mode. There are also those CPUs with h/w
>> breakpoint/watchpoint support which require the stub to use non-thumb
>> insns to manipulate.

> Would it be possible to provide macros for switching to ARM mode and 
> back for these cases? I would be more comfortable with that then, say, 
> compile certain files without -mthumb and enable thumb interworking.

Right, I think that is probably the best approach, but you don't have
to do it on a file by file basis. You can use the gcc __attribute__
mechanism to mark individual functions as arm or thumb code.

> How do you do it now? Do you use thumb code at all?

Personally, I've only ever run thumb code under gdb connected to a
RedBoot that was built as normal arm.

--Mark

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