[PATCH] ipa: Teach IPA-CP transformation about IPA-SRA modifications (PR 103227)

[Jan Hubicka]

> 
> gcc/ChangeLog:
> 
> 2021-11-23  Martin Jambor  <mjambor@suse.cz>
> 
> 	PR ipa/103227
> 	* ipa-prop.h (ipa_get_param): New overload.  Move bits of the existing
> 	one to the new one.
> 	* ipa-param-manipulation.h (ipa_param_adjustments): New member
> 	function get_updated_index_or_split.
> 	* ipa-param-manipulation.c
> 	(ipa_param_adjustments::get_updated_index_or_split): New function.
> 	* ipa-prop.c (adjust_agg_replacement_values): Reimplement, add
> 	capability to identify scalarized parameters and perform substitution
> 	on them.
> 	(ipcp_transform_function): Create descriptors earlier, handle new
> 	return values of adjust_agg_replacement_values.
> 
> gcc/testsuite/ChangeLog:
> 
> 2021-11-23  Martin Jambor  <mjambor@suse.cz>
> 
> 	PR ipa/103227
> 	* gcc.dg/ipa/pr103227-1.c: New test.
> 	* gcc.dg/ipa/pr103227-3.c: Likewise.
> 	* gcc.dg/ipa/pr103227-2.c: Likewise.
> 	* gfortran.dg/pr53787.f90: Disable IPA-SRA.
> ---
>  gcc/ipa-param-manipulation.c          | 33 ++++++++++++
>  gcc/ipa-param-manipulation.h          |  7 +++
>  gcc/ipa-prop.c                        | 73 +++++++++++++++++++--------
>  gcc/ipa-prop.h                        | 15 ++++--
>  gcc/testsuite/gcc.dg/ipa/pr103227-1.c | 29 +++++++++++
>  gcc/testsuite/gcc.dg/ipa/pr103227-2.c | 29 +++++++++++
>  gcc/testsuite/gcc.dg/ipa/pr103227-3.c | 52 +++++++++++++++++++
>  gcc/testsuite/gfortran.dg/pr53787.f90 |  2 +-
>  8 files changed, 216 insertions(+), 24 deletions(-)
>  create mode 100644 gcc/testsuite/gcc.dg/ipa/pr103227-1.c
>  create mode 100644 gcc/testsuite/gcc.dg/ipa/pr103227-2.c
>  create mode 100644 gcc/testsuite/gcc.dg/ipa/pr103227-3.c
> 
> diff --git a/gcc/ipa-param-manipulation.c b/gcc/ipa-param-manipulation.c
> index cec1dba701f..479c20b3871 100644
> --- a/gcc/ipa-param-manipulation.c
> +++ b/gcc/ipa-param-manipulation.c
> @@ -449,6 +449,39 @@ ipa_param_adjustments::get_updated_indices (vec<int> *new_indices)
>      }
>  }
>  
> +/* If a parameter with original INDEX has survived intact, return its new
> +   index.  Otherwise return -1.  In that case, if it has been split and there
> +   is a new parameter representing a portion at unit OFFSET for which a value
> +   of a TYPE can be substituted, store its new index into SPLIT_INDEX,
> +   otherwise store -1 there.  */
> +int
> +ipa_param_adjustments::get_updated_index_or_split (int index,
> +						   unsigned unit_offset,
> +						   tree type, int *split_index)
> +{
> +  unsigned adj_len = vec_safe_length (m_adj_params);
> +  for (unsigned i = 0; i < adj_len ; i++)

In ipa-modref I precompute this to map so we do not need to walk all
params, but the loop is probably not bad since functions do not have
tens of thousdands parameters :)

Can I use it in ipa-modref to discover what parameters was turned from
by-reference to scalar, too?
> +    {
> +      ipa_adjusted_param *apm = &(*m_adj_params)[i];
> +      if (apm->base_index != index)
> +	continue;
> +      if (apm->op == IPA_PARAM_OP_COPY)
> +	return i;
> +      if (apm->op == IPA_PARAM_OP_SPLIT
> +	  && apm->unit_offset == unit_offset)
> +	{
> +	  if (useless_type_conversion_p (apm->type, type))
> +	    *split_index = i;
> +	  else
> +	    *split_index = -1;
> +	  return -1;
> +	}
> +    }
> +
> +  *split_index = -1;
> +  return -1;
> +}
> +
>  /* Return the original index for the given new parameter index.  Return a
>     negative number if not available.  */
>  
> diff --git a/gcc/ipa-param-manipulation.h b/gcc/ipa-param-manipulation.h
> index 5adf8a22356..d1dad9fac73 100644
> --- a/gcc/ipa-param-manipulation.h
> +++ b/gcc/ipa-param-manipulation.h
> @@ -236,6 +236,13 @@ public:
>    void get_surviving_params (vec<bool> *surviving_params);
>    /* Fill a vector with new indices of surviving original parameters.  */
>    void get_updated_indices (vec<int> *new_indices);
> +  /* If a parameter with original INDEX has survived intact, return its new
> +     index.  Otherwise return -1.  In that case, if it has been split and there
> +     is a new parameter representing a portion at UNIT_OFFSET for which a value
> +     of a TYPE can be substituted, store its new index into SPLIT_INDEX,
> +     otherwise store -1 there.  */
> +  int get_updated_index_or_split (int index, unsigned unit_offset, tree type,
> +				  int *split_index);
>    /* Return the original index for the given new parameter index.  Return a
>       negative number if not available.  */
>    int get_original_index (int newidx);
> diff --git a/gcc/ipa-prop.c b/gcc/ipa-prop.c
> index e85df0971fc..a297f50e945 100644
> --- a/gcc/ipa-prop.c
> +++ b/gcc/ipa-prop.c
> @@ -5578,32 +5578,55 @@ ipcp_read_transformation_summaries (void)
>  }
>  
>  /* Adjust the aggregate replacements in AGGVAL to reflect parameters skipped in
> -   NODE.  */
> +   NODE but also if any parameter was IPA-SRAed into a scalar go ahead with
> +   substitution of the default_definitions of that new param with the
> +   appropriate constant.
>  
> -static void
> -adjust_agg_replacement_values (struct cgraph_node *node,
> -			       struct ipa_agg_replacement_value *aggval)
> +   Return two bools.  the first it true if at least one item in AGGVAL still
> +   exists and function body walk should go ahead.  The second is true if any
> +   values were already substituted for scalarized parameters and update_cfg
> +   shuld be run after replace_uses_by.  */
> +
> +static std::pair<bool, bool>
What a fancy C++ :)
> +adjust_agg_replacement_values (cgraph_node *node,
> +			       ipa_agg_replacement_value *aggval,
> +			       const vec<ipa_param_descriptor, va_gc>
> +			         &descriptors)

Patch is OK.
Thanks,
Honza