On Mon, Nov 11, 2013 at 3:00 PM, Ilya Enkovich <enkovich....@gmail.com> wrote: > 2013/11/11 Richard Biener <richard.guent...@gmail.com>: >> On Fri, Nov 8, 2013 at 11:03 AM, Ilya Enkovich <enkovich....@gmail.com> >> wrote: >>> 2013/11/8 Richard Biener <richard.guent...@gmail.com>: >>>> On Thu, Nov 7, 2013 at 7:55 PM, Jeff Law <l...@redhat.com> wrote: >>>>> On 11/07/13 04:50, Ilya Enkovich wrote: >>>>>> >>>>>> Hi, >>>>>> >>>>>> Here is an updated patch version. >>>>> >>>>> I think this needs to hold until we have a consensus on what the parameter >>>>> passing looks like for bounded pointers. >>>> >>>> I still think the best thing to do on GIMPLE is >>>> >>>> arg_2 = __builtin_ia32_bnd_arg (arg_1(D)); >>>> foo (arg_2); >>>> >>>> that is, make the parameter an implicit pair of {value, bound} where >>>> the bound is determined by the value going through a bound association >>>> builtin. No extra explicit argument to the calls so arguments match >>>> the fndecl and fntype. All the complexity is defered to the expander >>>> which can trivially lookup bound arguments via the SSA def (I suppose >>>> it does that anyway now for getting at the explicit bound argument now). >>>> >>>> As far as I can see (well, think), all currently passed bound arguments >>>> are the return value of such builtin already. >>> >>> All bounds are result of different builtin calls. Small example: >>> >>> int *global_p; >>> void foo (int *p) >>> { >>> int buf[10]; >>> bar (p, buf, global_p); >>> } >>> >>> >>> It is translated into: >>> >>> __bound_tmp.1_7 = __builtin_ia32_bndmk (&buf, 40); >>> __bound_tmp.1_6 = __builtin_ia32_arg_bnd (p_3(D)(ab)); >>> global_p.0_2 = global_p; >>> __bound_tmp.1_8 = __builtin_ia32_bndldx (&global_p, global_p.0_2); >>> bar (p_3(D)(ab), __bound_tmp.1_6, &buf, __bound_tmp.1_7, >>> global_p.0_2, __bound_tmp.1_8); >>> >>> Bounds binding via calls as you suggest may be done as following: >>> >>> __bound_tmp.1_7 = __builtin_ia32_bndmk (&buf, 40); >>> __bound_tmp.1_6 = __builtin_ia32_arg_bnd (p_3(D)(ab)); >>> global_p.0_2 = global_p; >>> __bound_tmp.1_8 = __builtin_ia32_bndldx (&global_p, global_p.0_2); >>> _9 = __builtin_bind_bounds (p_3(D)(ab), __bound_tmp.1_6); >>> _10 = __builtin_bind_bounds (&buf, __bound_tmp.1_7); >>> _11 = __builtin_bind_bounds (global_p.0_2, __bound_tmp.1_8); >>> bar (_9, _10, _11); >>> >>> Is it close to what you propose? >> >> Yes. > > Is there a way to bind bounds with structures in a similar way?
Not to have them easy to lookup in the SSA web. A long time ago I proposed to make SSA aggregates possible, so you could do tem_2 = __internal_bind_bounds (aggr(D), __bound_tmp.1_3, __bound_tmp.1_4, ...); bar (tem_2); (originally the SSA aggregates were supposed to make copy-propgagation possible using the SSA copy propagator, and of course I needed it for the middle-end array work) Not sure if that will give other people the creeps (expand would never expand the "load" from tem_2 but instead handle aggr as parameter). A slight complication is due to alias analysis which would be need to taught that bar performs a load of aggr. Richard. > For > SSA names I may easily find definition and check if it is a binding > builtin call. But for structures it is not possible. The way I see it > to mark all such args as addressable and load required bounds on > expand pass. > > Ilya >> >> Richard. >> >>> Ilya >>>> >>>> Richard. >>>> >>>> >>>> >>>>> Jeff