On Fri, Nov 08, 2013 at 10:37:00AM +0100, Richard Biener wrote:
> On Thu, Nov 7, 2013 at 5:00 PM, <tsaund...@mozilla.com> wrote:
> > From: Trevor Saunders <tsaund...@mozilla.com>
> >
> > Hi,
> >
> > This is the result of seeing what it would take to get rid of the has_gate
> > and
> > has_execute flags on pass_data. It turns out not much, but I wanted
> > confirmation this part is ok before I go deal with all the places that
> > initialize the fields.
> >
> > I bootstrapped this part on x86_64-unknown-linux-gnu and saw no new test
> > suite
> > regressions (ignoring the silk stuff because the full paths in its test
> > names
> > break my test script for now) Any reason this patch with the actual removal
> > of the flags wouldn't be ok?
>
> The has_gate flag is easy to remove (without a TODO_ hack), right?
> No gate simply means that the gate returns always true. The only
> weird thing is
>
> /* If we have a gate, combine the properties that we could have with
> and without the pass being examined. */
> if (pass->has_gate)
> properties &= new_properties;
> else
> properties = new_properties;
>
> which I don't understand (and you just removed all properties handling there).
>
> So can you split out removing has_gate? This part is obviously ok.
>
> Then, for ->execute () I'd have refactored the code to make
> ->sub passes explicitely executed by the default ->execute ()
> implementation only. That is, passes without overriding execute
> are containers only. Can you quickly check whether that would
> work out?
Ok, I've now given this a shot and wasn't terribly successful, if I just
change execute_pass_list and execute_ipa_pass_list to handle container
passes executing their sub passes I get the following ICE
./gt-passes.h:77:2: internal compiler error: Segmentation fault
};
^
0xd43d96 crash_signal
/src/gcc/gcc/toplev.c:334
0xd901a9 ssa_default_def(function*, tree_node*)
/src/gcc/gcc/tree-dfa.c:318
0xb56d77 ipa_analyze_params_uses
/src/gcc/gcc/ipa-prop.c:2094
0xb57275 ipa_analyze_node(cgraph_node*)
/src/gcc/gcc/ipa-prop.c:2179
0x13e2b6d ipcp_generate_summary
/src/gcc/gcc/ipa-cp.c:3615
0xc55a2a
execute_ipa_summary_passes(ipa_opt_pass_d*)
/src/gcc/gcc/passes.c:1991
0x943341 ipa_passes
/src/gcc/gcc/cgraphunit.c:2011
0x943675
compile()
/src/gcc/gcc/cgraphunit.c:2118
now
Which is because fn->gimple_df is null. I expect that's because pass
ordering changed somehow, but I'm not sure off hand how or ifthat's
something worth figuring out right now.
Another issue I realized is that doing this will change the order of
plugin events from
start container pass a
end container pass a
start contained pass b
end contained pass b
...
to
start container pass a
start contained pass b
end contained pass b
end container pass a
Arguably that's an improvement, but I'm not sure if changing that APi
like that is acceptable.
Trev
>
> Thanks,
> Richard.
>
> > Trev
> >
> > 2013-11-06 Trevor Saunders <tsaund...@mozilla.com>
> >
> > * pass_manager.h (pass_manager): Adjust.
> > * passes.c (opt_pass::execute): Tell the pass manager it doesn't
> > need
> > to do anything for this pass.
> > (pass_manager::register_dump_files_1): Don't uselessly deal with
> > properties of passes.
> > (pass_manager::register_dump_files): Adjust.
> > (dump_one_pass): Just call pass->gate ().
> > (execute_ipa_summary_passes): Likewise.
> > (execute_one_pass): Don't check pass->has_execute flag.
> > (ipa_write_summaries_2): Don't check pass->has_gate flag.
> > (ipa_write_optimization_summaries_1): Likewise.
> > (ipa_read_summaries_1): Likewise.
> > (ipa_read_optimization_summaries_1): Likewise.
> > (execute_ipa_stmt_fixups): Likewise.
> > * tree-pass.h (pass_data): Rename has_gate to useless_has_gate and
> > has_execute to useless_has_execute to be sure they're unused.
> > (TODO_absolutely_nothing): New constant.
> >
> >
> > diff --git a/gcc/pass_manager.h b/gcc/pass_manager.h
> > index 77d78eb..3bc0a99 100644
> > --- a/gcc/pass_manager.h
> > +++ b/gcc/pass_manager.h
> > @@ -93,7 +93,7 @@ public:
> >
> > private:
> > void set_pass_for_id (int id, opt_pass *pass);
> > - int register_dump_files_1 (struct opt_pass *pass, int properties);
> > + void register_dump_files_1 (struct opt_pass *pass);
> > void register_dump_files (struct opt_pass *pass, int properties);
> >
> > private:
> > diff --git a/gcc/passes.c b/gcc/passes.c
> > index 19e5869..3b28dc9 100644
> > --- a/gcc/passes.c
> > +++ b/gcc/passes.c
> > @@ -112,7 +112,7 @@ opt_pass::gate ()
> > unsigned int
> > opt_pass::execute ()
> > {
> > - return 0;
> > + return TODO_absolutely_nothing;
> > }
> >
> > opt_pass::opt_pass (const pass_data &data, context *ctxt)
> > @@ -701,33 +701,21 @@ pass_manager::register_one_dump_file (struct opt_pass
> > *pass)
> >
> > /* Recursive worker function for register_dump_files. */
> >
> > -int
> > +void
> > pass_manager::
> > -register_dump_files_1 (struct opt_pass *pass, int properties)
> > +register_dump_files_1 (struct opt_pass *pass)
> > {
> > do
> > {
> > - int new_properties = (properties | pass->properties_provided)
> > - & ~pass->properties_destroyed;
> > -
> > if (pass->name && pass->name[0] != '*')
> > register_one_dump_file (pass);
> >
> > if (pass->sub)
> > - new_properties = register_dump_files_1 (pass->sub, new_properties);
> > -
> > - /* If we have a gate, combine the properties that we could have with
> > - and without the pass being examined. */
> > - if (pass->has_gate)
> > - properties &= new_properties;
> > - else
> > - properties = new_properties;
> > + register_dump_files_1 (pass->sub);
> >
> > pass = pass->next;
> > }
> > while (pass);
> > -
> > - return properties;
> > }
> >
> > /* Register the dump files for the pass_manager starting at PASS.
> > @@ -739,7 +727,7 @@ pass_manager::
> > register_dump_files (struct opt_pass *pass,int properties)
> > {
> > pass->properties_required |= properties;
> > - register_dump_files_1 (pass, properties);
> > + register_dump_files_1 (pass);
> > }
> >
> > struct pass_registry
> > @@ -847,7 +835,7 @@ dump_one_pass (struct opt_pass *pass, int pass_indent)
> > const char *pn;
> > bool is_on, is_really_on;
> >
> > - is_on = pass->has_gate ? pass->gate () : true;
> > + is_on = pass->gate ();
> > is_really_on = override_gate_status (pass, current_function_decl, is_on);
> >
> > if (pass->static_pass_number <= 0)
> > @@ -2002,7 +1990,7 @@ execute_ipa_summary_passes (struct ipa_opt_pass_d
> > *ipa_pass)
> >
> > /* Execute all of the IPA_PASSes in the list. */
> > if (ipa_pass->type == IPA_PASS
> > - && ((!pass->has_gate) || pass->gate ())
> > + && pass->gate ()
> > && ipa_pass->generate_summary)
> > {
> > pass_init_dump_file (pass);
> > @@ -2153,7 +2141,7 @@ execute_one_pass (struct opt_pass *pass)
> >
> > /* Check whether gate check should be avoided.
> > User controls the value of the gate through the parameter
> > "gate_status". */
> > - gate_status = pass->has_gate ? pass->gate () : true;
> > + gate_status = pass->gate ();
> > gate_status = override_gate_status (pass, current_function_decl,
> > gate_status);
> >
> > /* Override gate with plugin. */
> > @@ -2210,11 +2198,11 @@ execute_one_pass (struct opt_pass *pass)
> > timevar_push (pass->tv_id);
> >
> > /* Do it! */
> > - if (pass->has_execute)
> > - {
> > - todo_after = pass->execute ();
> > - do_per_function (clear_last_verified, NULL);
> > - }
> > + todo_after = pass->execute ();
> > + if (todo_after != TODO_absolutely_nothing)
> > + do_per_function (clear_last_verified, NULL);
> > + else
> > + todo_after &= ~TODO_absolutely_nothing;
> >
> > /* Stop timevar. */
> > if (pass->tv_id != TV_NONE)
> > @@ -2286,7 +2274,7 @@ ipa_write_summaries_2 (struct opt_pass *pass, struct
> > lto_out_decl_state *state)
> > gcc_assert (pass->type == SIMPLE_IPA_PASS || pass->type == IPA_PASS);
> > if (pass->type == IPA_PASS
> > && ipa_pass->write_summary
> > - && ((!pass->has_gate) || pass->gate ()))
> > + && pass->gate ())
> > {
> > /* If a timevar is present, start it. */
> > if (pass->tv_id)
> > @@ -2402,7 +2390,7 @@ ipa_write_optimization_summaries_1 (struct opt_pass
> > *pass, struct lto_out_decl_s
> > gcc_assert (pass->type == SIMPLE_IPA_PASS || pass->type == IPA_PASS);
> > if (pass->type == IPA_PASS
> > && ipa_pass->write_optimization_summary
> > - && ((!pass->has_gate) || pass->gate ()))
> > + && pass->gate ())
> > {
> > /* If a timevar is present, start it. */
> > if (pass->tv_id)
> > @@ -2479,7 +2467,7 @@ ipa_read_summaries_1 (struct opt_pass *pass)
> > gcc_assert (!cfun);
> > gcc_assert (pass->type == SIMPLE_IPA_PASS || pass->type == IPA_PASS);
> >
> > - if ((!pass->has_gate) || pass->gate ())
> > + if (pass->gate ())
> > {
> > if (pass->type == IPA_PASS && ipa_pass->read_summary)
> > {
> > @@ -2530,7 +2518,7 @@ ipa_read_optimization_summaries_1 (struct opt_pass
> > *pass)
> > gcc_assert (!cfun);
> > gcc_assert (pass->type == SIMPLE_IPA_PASS || pass->type == IPA_PASS);
> >
> > - if ((!pass->has_gate) || pass->gate ())
> > + if (pass->gate ())
> > {
> > if (pass->type == IPA_PASS && ipa_pass->read_optimization_summary)
> > {
> > @@ -2608,7 +2596,7 @@ execute_ipa_stmt_fixups (struct opt_pass *pass,
> > {
> > /* Execute all of the IPA_PASSes in the list. */
> > if (pass->type == IPA_PASS
> > - && ((!pass->has_gate) || pass->gate ()))
> > + && pass->gate ())
> > {
> > struct ipa_opt_pass_d *ipa_pass = (struct ipa_opt_pass_d *) pass;
> >
> > diff --git a/gcc/tree-pass.h b/gcc/tree-pass.h
> > index 9efee1e..bed639e 100644
> > --- a/gcc/tree-pass.h
> > +++ b/gcc/tree-pass.h
> > @@ -49,11 +49,11 @@ struct pass_data
> >
> > /* If true, this pass has its own implementation of the opt_pass::gate
> > method. */
> > - bool has_gate;
> > + bool useless_has_gate;
> >
> > /* If true, this pass has its own implementation of the opt_pass::execute
> > method. */
> > - bool has_execute;
> > + bool useless_has_execute;
> >
> > /* The timevar id associated with this pass. */
> > /* ??? Ideally would be dynamically assigned. */
> > @@ -299,6 +299,10 @@ protected:
> > /* Rebuild the callgraph edges. */
> > #define TODO_rebuild_cgraph_edges (1 << 22)
> >
> > +/* Should only be used by opt_pass::execute to tell the pass manager the
> > pass
> > + did absolutely nothing. */
> > +#define TODO_absolutely_nothing 1 << 23
> > +
> > /* Internally used in execute_function_todo(). */
> > #define TODO_update_ssa_any \
> > (TODO_update_ssa \
> > --
> > 1.8.4.2
> >
