Re: [RFC] Bug lto/78140

[Richard Biener <richard dot guenther at gmail dot com>]

On Thu, Feb 2, 2017 at 1:52 PM, Richard Biener
<richard.guenther@gmail.com> wrote:
> On Thu, Feb 2, 2017 at 1:48 PM, Jan Hubicka <hubicka@ucw.cz> wrote:
>>>
>>> 2017-02-02  Kugan Vivekanandarajah  <kuganv@linaro.org>
>>>
>>>         * ipa-cp.c (ipcp_store_bits_results): Construct bits vector.
>>>         (ipcp_store_vr_results): Constrict m_vr vector.
>>>         * ipa-prop.c (ipa_node_params_t::remove): Set transaction summary to
>>> null.
>>>         (ipa_node_params_t::duplicate): Construct bits and m_vr vector.
>>>         (read_ipcp_transformation_info): Likewise.
>>>
>>>
>>> Thanks,
>>> Kugan
>>>
>>> >>I tried similar think without variable structure like:
>>> >>diff --git a/gcc/ipa-prop.h b/gcc/ipa-prop.h
>>> >>index 93a2390c..b0cc832 100644
>>> >>--- a/gcc/ipa-prop.h
>>> >>+++ b/gcc/ipa-prop.h
>>> >>@@ -525,7 +525,7 @@ struct GTY(()) ipcp_transformation_summary
>>> >>   /* Known bits information.  */
>>> >>   vec<ipa_bits, va_gc> *bits;
>>> >>   /* Value range information.  */
>>> >>-  vec<ipa_vr, va_gc> *m_vr;
>>> >>+  vec<ipa_vr *, va_gc> *m_vr;
>>> >> };
>>> >>
>>> >>This also has the same issue so I don't think it has anything to do with
>>> >>variable structure.
>>> >
>>> >You have to debug that detail yourself but I wonder why the transformation
>>> >summary has a different representation than the jump function (and I think
>>> >the jump function size is the issue).
>>> >
>>> >The JF has
>>> >
>>> >  /* Information about zero/non-zero bits.  */
>>> >  struct ipa_bits bits;
>>> >
>>> >  /* Information about value range, containing valid data only when vr_known is
>>> >     true.  */
>>> >  value_range m_vr;
>>> >  bool vr_known;
>>> >
>>> >with ipa_bits having two widest_ints and value_range having two trees
>>> >and an unused bitmap and ipa_vr having two wide_ints (widest_ints are
>>> >smaller!).
>>> >
>>> >Richard.
>>> >
>>> >>
>>> >>Thanks,
>>> >>Kugan
>>
>>> diff --git a/gcc/ipa-cp.c b/gcc/ipa-cp.c
>>> index aa3c997..5103555 100644
>>> --- a/gcc/ipa-cp.c
>>> +++ b/gcc/ipa-cp.c
>>> @@ -4865,6 +4865,8 @@ ipcp_store_bits_results (void)
>>>
>>>        ipcp_grow_transformations_if_necessary ();
>>>        ipcp_transformation_summary *ts = ipcp_get_transformation_summary (node);
>>> +      if (!ts->bits)
>>> +     ts->bits = (new (ggc_cleared_alloc<ipa_bits_vec> ()) ipa_bits_vec ());
>
>
> Why do you need those placement news?

Ah, I see we handle finalization but not construction in ggc_[cleared_]alloc...

> Richard.
>
>>>        vec_safe_reserve_exact (ts->bits, count);
>>>
>>>        for (unsigned i = 0; i < count; i++)
>>> @@ -4940,6 +4942,8 @@ ipcp_store_vr_results (void)
>>>
>>>        ipcp_grow_transformations_if_necessary ();
>>>        ipcp_transformation_summary *ts = ipcp_get_transformation_summary (node);
>>> +      if (!ts->m_vr)
>>> +     ts->m_vr = new (ggc_cleared_alloc<ipa_vr_vec> ()) ipa_vr_vec ();
>>>        vec_safe_reserve_exact (ts->m_vr, count);
>>>
>>>        for (unsigned i = 0; i < count; i++)
>>> diff --git a/gcc/ipa-prop.c b/gcc/ipa-prop.c
>>> index 834c27d..b992a7f 100644
>>> --- a/gcc/ipa-prop.c
>>> +++ b/gcc/ipa-prop.c
>>> @@ -3759,13 +3759,20 @@ ipa_node_params_t::insert (cgraph_node *, ipa_node_params *info)
>>>     to.  */
>>>
>>>  void
>>> -ipa_node_params_t::remove (cgraph_node *, ipa_node_params *info)
>>> +ipa_node_params_t::remove (cgraph_node *node, ipa_node_params *info)
>>>  {
>>>    free (info->lattices);
>>>    /* Lattice values and their sources are deallocated with their alocation
>>>       pool.  */
>>>    info->known_csts.release ();
>>>    info->known_contexts.release ();
>>> +  ipcp_transformation_summary *ts = ipcp_get_transformation_summary (node);
>>> +  if (ts != NULL)
>>> +    {
>>> +      ts->agg_values = NULL;
>>> +      ts->bits = NULL;
>>> +      ts->m_vr = NULL;
>>> +    }
>>
>> I would go for explicit ggc_free for them: garbage collrector is hardly ever run during
>> WPA stage and thus we are not going to get the memory back otherwise.
>>
>> Patch is OK with that change.
>>
>> Honza
>>>  }
>>>
>>>  /* Hook that is called by summary when a node is duplicated.  */
>>> @@ -3811,8 +3818,10 @@ ipa_node_params_t::duplicate(cgraph_node *src, cgraph_node *dst,
>>>        ipcp_grow_transformations_if_necessary ();
>>>        src_trans = ipcp_get_transformation_summary (src);
>>>        const vec<ipa_vr, va_gc> *src_vr = src_trans->m_vr;
>>> -      vec<ipa_vr, va_gc> *&dst_vr
>>> -     = ipcp_get_transformation_summary (dst)->m_vr;
>>> +      ipcp_transformation_summary *dts = ipcp_get_transformation_summary (dst);
>>> +      if (!dts->m_vr)
>>> +     dts->m_vr = (new (ggc_cleared_alloc<ipa_vr_vec> ()) ipa_vr_vec ());
>>> +      vec<ipa_vr, va_gc> *&dst_vr = dts->m_vr;
>>>        if (vec_safe_length (src_trans->m_vr) > 0)
>>>       {
>>>         vec_safe_reserve_exact (dst_vr, src_vr->length ());
>>> @@ -3826,8 +3835,10 @@ ipa_node_params_t::duplicate(cgraph_node *src, cgraph_node *dst,
>>>        ipcp_grow_transformations_if_necessary ();
>>>        src_trans = ipcp_get_transformation_summary (src);
>>>        const vec<ipa_bits, va_gc> *src_bits = src_trans->bits;
>>> -      vec<ipa_bits, va_gc> *&dst_bits
>>> -     = ipcp_get_transformation_summary (dst)->bits;
>>> +      ipcp_transformation_summary *dts = ipcp_get_transformation_summary (dst);
>>> +      if (!dts->bits)
>>> +     dts->bits = (new (ggc_cleared_alloc<ipa_bits_vec> ()) ipa_bits_vec ());
>>> +      vec<ipa_bits, va_gc> *&dst_bits = dts->bits;
>>>        vec_safe_reserve_exact (dst_bits, src_bits->length ());
>>>        for (unsigned i = 0; i < src_bits->length (); ++i)
>>>       dst_bits->quick_push ((*src_bits)[i]);
>>> @@ -5283,6 +5294,8 @@ read_ipcp_transformation_info (lto_input_block *ib, cgraph_node *node,
>>>        ipcp_grow_transformations_if_necessary ();
>>>
>>>        ipcp_transformation_summary *ts = ipcp_get_transformation_summary (node);
>>> +      if (!ts->m_vr)
>>> +     ts->m_vr = new (ggc_cleared_alloc<ipa_vr_vec> ()) ipa_vr_vec ();
>>>        vec_safe_grow_cleared (ts->m_vr, count);
>>>        for (i = 0; i < count; i++)
>>>       {
>>> @@ -5306,6 +5319,8 @@ read_ipcp_transformation_info (lto_input_block *ib, cgraph_node *node,
>>>        ipcp_grow_transformations_if_necessary ();
>>>
>>>        ipcp_transformation_summary *ts = ipcp_get_transformation_summary (node);
>>> +      if (!ts->bits)
>>> +     ts->bits = (new (ggc_cleared_alloc<ipa_bits_vec> ()) ipa_bits_vec ());
>>>        vec_safe_grow_cleared (ts->bits, count);
>>>
>>>        for (i = 0; i < count; i++)
>>> diff --git a/gcc/ipa-prop.h b/gcc/ipa-prop.h
>>> index 93a2390c..6573a78 100644
>>> --- a/gcc/ipa-prop.h
>>> +++ b/gcc/ipa-prop.h
>>> @@ -528,6 +528,9 @@ struct GTY(()) ipcp_transformation_summary
>>>    vec<ipa_vr, va_gc> *m_vr;
>>>  };
>>>
>>> +typedef vec<ipa_vr, va_gc>  ipa_vr_vec;
>>> +typedef vec<ipa_bits, va_gc>  ipa_bits_vec;
>>> +
>>>  void ipa_set_node_agg_value_chain (struct cgraph_node *node,
>>>                                  struct ipa_agg_replacement_value *aggvals);
>>>  void ipcp_grow_transformations_if_necessary (void);
>>