On Fri, 12 Apr 2013, Richard Biener wrote:
> On Fri, 12 Apr 2013, Steven Bosscher wrote:
>
> > On Thu, Apr 11, 2013 at 12:47 PM, Richard Biener wrote:
> > > That said - I'm positively sure I will hit the IRA / reload
> > > issue again when adding mandatory IL verification (though
> > > for that they can simply drop the properties).
> > >
> > > So, if we ignore that "GC boundary" is global we can add
> > > PROP_gc_safe, provided by default, removed by IRA and
> > > re-added by reload.
> >
> > What about the various pieces of GC-unsafe "black box" objects like
> > edge->aux, basic_block->aux, loop->aux, etc.?
> >
> > E.g. PR56921 looks like a "struct niter_desc" gets garbage collected
> > even though a loop still points to it via its aux field (NB I'm just
> > guessing, not verified).
>
> I don't see how we were "safe" here before this patch. Yes,
> appearantly we didn't collect between those passes - but that
> appears to be for no good reason as breaking the GC barrier
> would certainly be a good reason for a comment.
>
> Which means that for the resolution of this thread we probably
> want to settle on TODO_no_ggc_collect which is quite explicit.
>
> Oh, but please document _what_ is the data that is kept live
> cross-pass at the point you add TODO_no_ggc_collect.
FYI, the following is what I am currently bootstrapping and
regtesting. It adds TODO_do_not_ggc_collect and reverts
the IRA/reload merge.
I'm going to commit it after bootstrap/testing on x86_64-unknown-linux-gnu
unless someone objects (soon).
Thanks,
Richard.
2013-04-12 Richard Biener <rguent...@suse.de>
* tree-pass.h (TODO_do_not_ggc_collect): New.
* passes.c (execute_one_ipa_transform_pass): Honor
TODO_do_not_ggc_collect.
(execute_one_pass): Likewise.
Revert
2013-04-10 Richard Biener <rguent...@suse.de>
* passes.c (init_optimization_passes): Remove reload pass.
* ira.c (do_reload): Merge into ...
(ira): ... this.
(rest_of_handle_reload): Remove.
(pass_reload): Likewise.
* config/i386/i386.c (ix86_option_override): Refer to ira instead
of reload for vzeroupper pass placement.
* g++.dg/pr55604.C: Use -fdump-rtl-ira.
Index: gcc/tree-pass.h
===================================================================
*** gcc/tree-pass.h.orig 2013-04-12 10:06:03.000000000 +0200
--- gcc/tree-pass.h 2013-04-12 10:06:05.278958138 +0200
*************** struct simple_ipa_opt_pass
*** 154,159 ****
--- 154,160 ----
(PROP_gimple_any | PROP_gimple_lcf | PROP_gimple_leh | PROP_gimple_lomp)
/* To-do flags. */
+ #define TODO_do_not_ggc_collect (1 << 1)
#define TODO_verify_ssa (1 << 2)
#define TODO_verify_flow (1 << 3)
#define TODO_verify_stmts (1 << 4)
*************** extern struct rtl_opt_pass pass_mode_swi
*** 445,450 ****
--- 446,452 ----
extern struct rtl_opt_pass pass_sms;
extern struct rtl_opt_pass pass_sched;
extern struct rtl_opt_pass pass_ira;
+ extern struct rtl_opt_pass pass_reload;
extern struct rtl_opt_pass pass_clean_state;
extern struct rtl_opt_pass pass_branch_prob;
extern struct rtl_opt_pass pass_value_profile_transformations;
Index: gcc/passes.c
===================================================================
*** gcc/passes.c.orig 2013-04-12 10:06:03.000000000 +0200
--- gcc/passes.c 2013-04-12 10:06:05.279958149 +0200
*************** init_optimization_passes (void)
*** 1620,1625 ****
--- 1620,1626 ----
NEXT_PASS (pass_sms);
NEXT_PASS (pass_sched);
NEXT_PASS (pass_ira);
+ NEXT_PASS (pass_reload);
NEXT_PASS (pass_postreload);
{
struct opt_pass **p = &pass_postreload.pass.sub;
*************** execute_one_ipa_transform_pass (struct c
*** 2186,2192 ****
current_pass = NULL;
/* Signal this is a suitable GC collection point. */
! ggc_collect ();
}
/* For the current function, execute all ipa transforms. */
--- 2187,2194 ----
current_pass = NULL;
/* Signal this is a suitable GC collection point. */
! if (!(todo_after & TODO_do_not_ggc_collect))
! ggc_collect ();
}
/* For the current function, execute all ipa transforms. */
*************** execute_one_pass (struct opt_pass *pass)
*** 2365,2371 ****
current_pass = NULL;
/* Signal this is a suitable GC collection point. */
! ggc_collect ();
return true;
}
--- 2367,2374 ----
current_pass = NULL;
/* Signal this is a suitable GC collection point. */
! if (!((todo_after | pass->todo_flags_finish) & TODO_do_not_ggc_collect))
! ggc_collect ();
return true;
}
Index: gcc/ira.c
===================================================================
*** gcc/ira.c.orig 2013-04-12 10:06:03.000000000 +0200
--- gcc/ira.c 2013-04-12 10:06:27.824203322 +0200
*************** ira (FILE *f)
*** 4359,4366 ****
int rebuild_p;
bool saved_flag_caller_saves = flag_caller_saves;
enum ira_region saved_flag_ira_region = flag_ira_region;
- basic_block bb;
- bool need_dce;
ira_conflicts_p = optimize > 0;
--- 4359,4364 ----
*************** ira (FILE *f)
*** 4590,4595 ****
--- 4588,4600 ----
flag_caller_saves = saved_flag_caller_saves;
flag_ira_region = saved_flag_ira_region;
}
+ }
+
+ static void
+ do_reload (void)
+ {
+ basic_block bb;
+ bool need_dce;
if (flag_ira_verbose < 10)
ira_dump_file = dump_file;
*************** ira (FILE *f)
*** 4629,4634 ****
--- 4634,4641 ----
timevar_pop (TV_RELOAD);
+ timevar_push (TV_IRA);
+
if (ira_conflicts_p && ! ira_use_lra_p)
{
ira_free (ira_spilled_reg_stack_slots);
*************** ira (FILE *f)
*** 4686,4691 ****
--- 4693,4700 ----
if (need_dce && optimize)
run_fast_dce ();
+
+ timevar_pop (TV_IRA);
}
/* Run the integrated register allocator. */
*************** struct rtl_opt_pass pass_ira =
*** 4712,4717 ****
0, /* properties_provided */
0, /* properties_destroyed */
0, /* todo_flags_start */
! 0 /* todo_flags_finish */
}
};
--- 4721,4753 ----
0, /* properties_provided */
0, /* properties_destroyed */
0, /* todo_flags_start */
! TODO_do_not_ggc_collect /* todo_flags_finish */
! }
! };
!
! static unsigned int
! rest_of_handle_reload (void)
! {
! do_reload ();
! return 0;
! }
!
! struct rtl_opt_pass pass_reload =
! {
! {
! RTL_PASS,
! "reload", /* name */
! OPTGROUP_NONE, /* optinfo_flags */
! NULL, /* gate */
! rest_of_handle_reload, /* execute */
! NULL, /* sub */
! NULL, /* next */
! 0, /* static_pass_number */
! TV_RELOAD, /* tv_id */
! 0, /* properties_required */
! 0, /* properties_provided */
! 0, /* properties_destroyed */
! 0, /* todo_flags_start */
! 0 /* todo_flags_finish */
}
};
Index: gcc/testsuite/g++.dg/pr55604.C
===================================================================
*** gcc/testsuite/g++.dg/pr55604.C.orig 2013-04-12 10:06:03.000000000 +0200
--- gcc/testsuite/g++.dg/pr55604.C 2013-04-12 10:06:05.281958171 +0200
***************
*** 1,5 ****
/* { dg-do compile } */
! /* { dg-options "-O -fdump-rtl-ira" } */
main ()
{
--- 1,5 ----
/* { dg-do compile } */
! /* { dg-options "-O -fdump-rtl-reload" } */
main ()
{
*************** main ()
*** 8,11 ****
__builtin_printf ("%d %s\n", t, s);
}
! /* { dg-final { cleanup-rtl-dump "ira" } } */
--- 8,11 ----
__builtin_printf ("%d %s\n", t, s);
}
! /* { dg-final { cleanup-rtl-dump "reload" } } */
Index: gcc/config/i386/i386.c
===================================================================
*** gcc/config/i386/i386.c.orig 2013-04-10 13:36:55.000000000 +0200
--- gcc/config/i386/i386.c 2013-04-12 10:11:53.780748099 +0200
*************** static void
*** 3930,3936 ****
ix86_option_override (void)
{
static struct register_pass_info insert_vzeroupper_info
! = { &pass_insert_vzeroupper.pass, "ira",
1, PASS_POS_INSERT_AFTER
};
--- 3930,3936 ----
ix86_option_override (void)
{
static struct register_pass_info insert_vzeroupper_info
! = { &pass_insert_vzeroupper.pass, "reload",
1, PASS_POS_INSERT_AFTER
};
