Re: [Qemu-devel] [PATCH] Revived GUEST_BASE support for usermode emulation targets [v4]

[Paul Brook]

> > It is indeed broken. Since tcg_out_addi maps on x86_64 to tgen_arithi64
> > which doesn't accept 64bit values. But as Martin said, the currrent use
> > for this patch is just to add very minimal offsets.
>
> I that case you should be using lea for small offsets. The proper sequence
> for large offsets is movq (allows 64-bit immedaise); add.
>
> The offset is a user configurable option, so IMHO you should be supporting
> large offsets.

I'll also note that mmap_min_addr need not be a small value. It may be set to 
~4G to flush out 32-bit pointer truncation errors.

Paul