Re: [PATCH v6 04/26] plugins: Drop tcg_flags from struct qemu_plugin_dyn_cb

[Richard Henderson]

On 5/16/21 7:53 AM, Philippe Mathieu-Daudé wrote:
> > -    op->args[*cb_idx + 1] = tcg_flags;
> > +    op->args[*cb_idx + 1] = (*begin_op)->args[*cb_idx + 1];
>
> I don't understand this change, can you explain?

This patch drops a mostly-unimplemented feature from plugins, where in theory 
the registration of the plugin would specify the TCG_CALL_* flags.

Instead, take the flags from the plugin template function -- i.e. copy them 
across from the original begin_op.

> > -static inline uint32_t cb_to_tcg_flags(enum qemu_plugin_cb_flags flags)
> > -{
> > -    uint32_t ret;
> > -
> > -    switch (flags) {
> > -    case QEMU_PLUGIN_CB_RW_REGS:
> > -        ret = 0;
> > -        break;
> > -    case QEMU_PLUGIN_CB_R_REGS:
> > -        ret = TCG_CALL_NO_WG;
> > -        break;
> > -    case QEMU_PLUGIN_CB_NO_REGS:
> > -    default:
> > -        ret = TCG_CALL_NO_RWG;
> > -    }
> > -    return ret;
> > -}

This is where the plugin interface was supposed to convert flags from one form 
to another.  This got stored in a structure and then passed along as an 
argument to the function containing that first hunk above.


r~