[OE-core] [PATCH 00/29] Add gobject introspection support to oe-core

[Mark Hatle]

On 11/13/15 10:12 AM, alexander.kanavin at linux.intel.com wrote:
>>> Hmm, maybe it's simpler to just fix QEMU so it can handle the missing
>>> instructions?
>>
>> Unfortunately it's not reasonable in my experience.  The problem is that
>> anyone
>> who implements a BSP/machine that includes so far unknown instructions to
>> qemu
>> would be required to implement them.
>>
>> As most people don't understand the instruction implementation in QEMU,
>> I'm not
>> sure this is reasonable.
> 
> If someone is competent enough to add new instructions to the compiler,
> they should be competent enough to figure out how to do the same in QEMU,
> no?

That's the problem right there.  The same developers rarely do that work.

The compiler today support many more instructions for a given architecture
family then QEMU models for that same architecture.

IA32 -- some of the current and even some former generate i7 instructions fall
under this problem.  If you host system does not have the same instruction set,
QEMU doesn't know how to emulate everything.

MIPS64 (Such as the Octeon III) is a good example.

PowerPC has many variants as well that QEMU does not support.

It would be wonderful if there was a tie together of what gcc/as and qemu
supported -- at least from an application perspective, but that simply doesn't
happen in the real world.

--Mark

> Alex
>