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Re: SVC (SWI) for Thumb

> Setting an 8 bit value costs one instruction in userspace, but
> probably removes one from the kernel side

So in time, it's a wash, but in space, you have one instruction per
syscall in the kernel versus of one instruction per syscall per program
in userland.  This seems to me like a clear win for keeping the
instruction in the kernel - especially if you're not sure it goes away
in the kernel.

Unless I'm missing someting - I don't really know thumb, just going on
what you wrote.

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