RE: [PATCH v4 24/33] target/nios2: Introduce shadow register sets

[Amir Gonnen]

Hi Richard,

How does "cpu_crs_R" work?
In your version you hold a pointer to the current register set instead of 
copying registers back and forth like I did, which makes sense.

But how does TCG know which set to refer to when it generates code?
It looks like it's always accessing the same cpu_crs_R, so how does it relate 
to the correct register set on "shadow_regs"?

In fact, I imagined it would be necessary to change "cpu_get_tb_cpu_state" and 
set "cs_base" or "flags" to STATUS.CRS such that different code would be 
generated for each shadow instance. Otherwise, each gpr access would be 
indirect. I'm probably missing something here.

Thanks,
Amir