On 6 October 2017 at 06:04, Jan Hubicka <hubi...@ucw.cz> wrote:
>> Hi Honza,
>> Thanks for the detailed suggestions, I have updated the patch accordingly.
>> I have following questions on call_summary:
>> 1] I added field bool is_return_callee in ipa_call_summary to track
>> whether the caller possibly returns value returned by callee, which
>> gets rid of return_callees_map. I assume ipa_call_summary_t::remove()
>> and ipa_call_summary_t::duplicate() will already take care of handling
>> late insertion/removal of cgraph nodes ? I just initialized
>> is_return_callee to false in ipa_call_summary::reset and that seems to
>> work. I am not sure though if I have handled it correctly. Could you
>> please check that ?
>
> I was actually thinking to introduce separate summary for ipa-pure-const pass,
> but this seems fine to me too (for one bit definitly more effecient)
> ipa_call_summary_t::duplicate copies all the fields, so indeed you should be
> safe here.
>
> Also it is possible for functions to be inserted late. Updating of call
> summaries
> is currently handled by ipa_fn_summary_t::insert
>>
>> 2] ipa_inline() called ipa_free_fn_summary, which made
>> ipa_call_summaries unavailable during ipa-pure-const pass. I removed
>> call to ipa_free_fn_summary from ipa_inline, and moved it to
>> ipa_pure_const::execute(). Is that OK ?
>
> Seems OK to me.
>>
>> Patch passes bootstrap+test and lto bootstrap+test on
>> x86_64-unknown-linux-gnu.
>> Verfiied SPEC2k6 compiles and runs without miscompares with LTO
>> enabled on aarch64-linux-gnu.
>> Cross-tested on arm*-*-* and aarch64*-*-*. I will additionally test
>> the patch by building chromium or firefox.
>> Would it be OK to commit if it passes above validations ?
>>
>> Thanks,
>> Prathamesh
>> >
>> > Thanks,
>> > Honza
>
>> 2017-10-05 Prathamesh Kulkarni <prathamesh.kulka...@linaro.org>
>>
>> * cgraph.h (set_malloc_flag): Declare.
>> * cgraph.c (set_malloc_flag_1): New function.
>> (set_malloc_flag): Likewise.
>> * ipa-fnsummary.h (ipa_call_summary): Add new field is_return_callee.
>> * ipa-fnsummary.c (ipa_call_summary::reset): Set is_return_callee to
>> false.
>> (read_ipa_call_summary): Add support for reading is_return_callee.
>> (write_ipa_call_summary): Stream is_return_callee.
>> * ipa-inline.c (ipa_inline): Remove call to ipa_free_fn_summary.
>> * ipa-pure-const.c: Add headers ssa.h, alloc-pool.h, symbol-summary.h,
>> ipa-prop.h, ipa-fnsummary.h.
>> (malloc_state_e): Define.
>> (malloc_state_names): Define.
>> (funct_state_d): Add field malloc_state.
>> (varying_state): Set malloc_state to STATE_MALLOC_BOTTOM.
>> (check_retval_uses): New function.
>> (malloc_candidate_p): Likewise.
>> (analyze_function): Add support for malloc attribute.
>> (pure_const_write_summary): Stream malloc_state.
>> (pure_const_read_summary): Add support for reading malloc_state.
>> (dump_malloc_lattice): New function.
>> (propagate_malloc): New function.
>> (ipa_pure_const::execute): Call propagate_malloc and
>> ipa_free_fn_summary.
>> (pass_local_pure_const::execute): Add support for malloc attribute.
>> * ssa-iterators.h (RETURN_FROM_IMM_USE_STMT): New macro.
>>
>> testsuite/
>> * gcc.dg/ipa/propmalloc-1.c: New test-case.
>> * gcc.dg/ipa/propmalloc-2.c: Likewise.
>> * gcc.dg/ipa/propmalloc-3.c: Likewise.
>>
>> diff --git a/gcc/cgraph.c b/gcc/cgraph.c
>> index 3d0cefbd46b..0aad90d59ea 100644
>> --- a/gcc/cgraph.c
>> +++ b/gcc/cgraph.c
>> @@ -2530,6 +2530,53 @@ cgraph_node::set_nothrow_flag (bool nothrow)
>> return changed;
>> }
>>
>> +/* Worker to set malloc flag. */
> New line here I guess (it is below)
>> +static void
>> +set_malloc_flag_1 (cgraph_node *node, bool malloc_p, bool *changed)
>> +{
>> + if (malloc_p && !DECL_IS_MALLOC (node->decl))
>> + {
>> + DECL_IS_MALLOC (node->decl) = true;
>> + *changed = true;
>> + }
>> +
>> + ipa_ref *ref;
>> + FOR_EACH_ALIAS (node, ref)
>> + {
>> + cgraph_node *alias = dyn_cast<cgraph_node *> (ref->referring);
>> + if (!malloc_p || alias->get_availability () > AVAIL_INTERPOSABLE)
>> + set_malloc_flag_1 (alias, malloc_p, changed);
>> + }
>> +
>> + for (cgraph_edge *e = node->callers; e; e = e->next_caller)
>> + if (e->caller->thunk.thunk_p
>> + && (!malloc_p || e->caller->get_availability () > AVAIL_INTERPOSABLE))
>> + set_malloc_flag_1 (e->caller, malloc_p, changed);
>> +}
>> +
>> +/* Set DECL_IS_MALLOC on NODE's decl and on NODE's aliases if any. */
>> +
>> +bool
>> +cgraph_node::set_malloc_flag (bool malloc_p)
>> +{
>> + bool changed = false;
>> +
>> + if (!malloc_p || get_availability () > AVAIL_INTERPOSABLE)
>> + set_malloc_flag_1 (this, malloc_p, &changed);
>> + else
>> + {
>> + ipa_ref *ref;
>> +
>> + FOR_EACH_ALIAS (this, ref)
>> + {
>> + cgraph_node *alias = dyn_cast<cgraph_node *> (ref->referring);
>> + if (!malloc_p || alias->get_availability () > AVAIL_INTERPOSABLE)
>> + set_malloc_flag_1 (alias, malloc_p, &changed);
>> + }
>> + }
>> + return changed;
>> +}
>> +
>> diff --git a/gcc/ipa-fnsummary.h b/gcc/ipa-fnsummary.h
>> index f50d6806e61..613a2b6f625 100644
>> --- a/gcc/ipa-fnsummary.h
>> +++ b/gcc/ipa-fnsummary.h
>> @@ -197,7 +197,9 @@ struct ipa_call_summary
>> int call_stmt_time;
>> /* Depth of loop nest, 0 means no nesting. */
>> unsigned int loop_depth;
>> -
>> + /* Indicates whether the caller returns the value of it's callee. */
> Perhaps add a comment when it is initialized.
> Don't you also check that the calle is not captured? In that case I would
> is_return_callee_uncaptured or so, so someone does not try to use it with
> different meaning.
Sorry, I didn't understand "Don't you also check that callee is not captured ?"
What does capturing mean in this context ?
Thanks,
Prathamesh
>
>> @@ -69,6 +74,15 @@ enum pure_const_state_e
>>
>> const char *pure_const_names[3] = {"const", "pure", "neither"};
>>
>> +enum malloc_state_e
>> +{
>> + STATE_MALLOC_TOP,
>> + STATE_MALLOC,
>> + STATE_MALLOC_BOTTOM
>> +};
>> +
>> +const char *malloc_state_names[] = {"malloc_top", "malloc",
>> "malloc_bottom"};
>
> Seems static is missing in all those declarations, please fix it.
>
> OK with these changes. Thanks!
>
> Honza
