Re: [PATCH v7 04/27] plugins: Drop tcg_flags from struct qemu_plugin_dyn_cb

[Richard Henderson]

On 6/2/21 2:22 AM, Alex Bennée wrote:
> Richard Henderson <richard.henderson@linaro.org> writes:
>
> > As noted by qemu-plugins.h, enum qemu_plugin_cb_flags is
> > currently unused -- plugins can neither read nor write
> > guest registers.
>
> No objection to this - although we hopefully will introduce the ability
> to read registers at some point. I saw no indication that the ability to
> mark helpers for that is going away, just the mechanism is changing?

The mechanism is going away.  I'll figure out how to replace it when there's 
some call to do so.


> > @@ -411,7 +411,7 @@ static TCGOp *copy_call(TCGOp **begin_op, TCGOp *op, void 
> > *empty_func,
> >           tcg_debug_assert(i < MAX_OPC_PARAM_ARGS);
> >       }
> >       op->args[*cb_idx] = (uintptr_t)func;
> > -    op->args[*cb_idx + 1] = tcg_flags;
> > +    op->args[*cb_idx + 1] = (*begin_op)->args[*cb_idx + 1];
>
> This confuses me. We are dropping tcg_flags because we aren't using them
> but why are we copying the next args from begin_op? Should we have been
> doing that before?

You were overwriting the field before, now we're copying it.


r~