[Qemu-devel] 4G address space remapping on 64-bit host

[Blue Swirl]

Hi,

I had an idea of mapping the full 32-bit target virtual address space
to a 4GB area on 64-bit hosts. Then the loads and stores to normal RAM
(except page tables, code_mem_write etc) could be made much faster,
falling back to softmmu for other pages. The idea has come up before,
for example in this Fabrice's message:
http://article.gmane.org/gmane.comp.emulators.qemu/685

But I'm not sure if this would be worth the effort, the speedup would
depend on the frequency of the loads/stores and also translation time
vs. translated code execution times. Does anyone have good statistics
on those?