Re: [PATCH v2 6/7] target/nios2: Remove assignment to env in handle_instruction

[Peter Maydell]

On Sun, 20 Jun 2021 at 23:15, Richard Henderson
<richard.henderson@linaro.org> wrote:
>
> Direct assignments to env during translation do not work.
>
> As it happens, the only way we can get here is if env->pc
> is already set to dc->pc.

More to the point, t_gen_helper_raise_exception() does
    tcg_gen_movi_tl(dc->cpu_R[R_PC], dc->pc);
before raising the exception (as you would expect it to).

> Signed-off-by: Richard Henderson <richard.henderson@linaro.org>
> ---
>  target/nios2/translate.c | 3 ++-
>  1 file changed, 2 insertions(+), 1 deletion(-)
>
> diff --git a/target/nios2/translate.c b/target/nios2/translate.c
> index 06705c894d..31f63d9faa 100644
> --- a/target/nios2/translate.c
> +++ b/target/nios2/translate.c
> @@ -740,14 +740,15 @@ static void handle_instruction(DisasContext *dc, 
> CPUNios2State *env)
>      uint32_t code;
>      uint8_t op;
>      const Nios2Instruction *instr;
> +
>  #if defined(CONFIG_USER_ONLY)
>      /* FIXME: Is this needed ? */
>      if (dc->pc >= 0x1000 && dc->pc < 0x2000) {
> -        env->regs[R_PC] = dc->pc;
>          t_gen_helper_raise_exception(dc, 0xaa);
>          return;
>      }
>  #endif
> +
>      code = cpu_ldl_code(env, dc->pc);
>      op = get_opcode(code);

Reviewed-by: Peter Maydell <peter.maydell@linaro.org>
but you probably want to tweak the commit message.

thanks
-- PMM