Re: How the cpu_R in DisasContext is associated with register of CPUArchState

[Peter Maydell]

On Fri, 3 Jul 2020 at 15:15, 沈梦姣 <shen.mengjiao3@icloud.com> wrote:
>
> Because in translate stage when write cpu register by guest code, it operates 
> totally on cpu_R of DisasContext, how to reflect it to register of 
> CPUArchState?

You don't say which target you're looking at, but in general
these mappings are set up when the translator is initialized.
For instance for Arm, arm_translate_init() does this:
    for (i = 0; i < 16; i++) {
        cpu_R[i] = tcg_global_mem_new_i32(cpu_env,
                                          offsetof(CPUARMState, regs[i]),
                                          regnames[i]);
    }

which creates the cpu_R[] TCGvs as TCG global variables which
live in the regs[] field of the CPUARMState structure. Whenever
TCG code is generated that accesses that global it will read
and write from the memory location corresponding to the
regs[] array entry in the CPU struct.

thanks
-- PMM