Re: [Qemu-devel] Optimization for amd CPUs without amd-v using sse2, 3, 4 instructions

[陳韋任]

> I am using qemu to run VMs on my computer with amd chip on board.
> However, my computer doesn't support amd-v, so the performance of the VM is 
> low.
> I do have experiences in optimization of program using sse technique.
> Is it possible to speed up the qemu for those x86 chips that do not support 
> hardware virtualization using sse instructions  ?
> If so, I would like to contribute the the qemu community.

  Without hardware virtualization (amd-v, for example), QEMU uses binary
translation to run your VM. That says each guest instruction executed by
the VM is translated into TCG ops (QEMU IR), then translated into host
instructions and executed. Perhaps you have to look at tcg/i386/*, which
is the TCG ops -> host binary part. Or, you can look at target-i386/*,
which is the guest binary -> TCG ops part. Currently, guest SIMD instruction
is emulated by helper functions in scalar manner. Maybe you can try to map
guest SIMD into host SIMD.

  Good Luck!

Regards,
chenwj 

-- 
Wei-Ren Chen (陳韋任)
Computer Systems Lab, Institute of Information Science,
Academia Sinica, Taiwan (R.O.C.)
Tel:886-2-2788-3799 #1667
Homepage: http://people.cs.nctu.edu.tw/~chenwj