Break out ao_ref_init_from_ptr_and_range from ao_ref_init_from_ptr_and_size

Hi,
this patch breaks out logic from ao_ref_init_from_ptr_and_size so i can
use it from ipa-modref oracle to to initialize ao_ref when
OFFSET/SIZE/MAX_SIZE is known.

Bootstrapped/regtested x86_64-linux together with the ipa-modref change,
OK?

Honza

	* tree-ssa-alias.c (ao_ref_init_from_ptr_and_range): Break out from ...
	(ao_ref_init_from_ptr_and_size): ... here.

On Fri, 2 Oct 2020, Jan Hubicka wrote:

> Hi,
> this patch breaks out logic from ao_ref_init_from_ptr_and_size so i can
> use it from ipa-modref oracle to to initialize ao_ref when
> OFFSET/SIZE/MAX_SIZE is known.
> 
> Bootstrapped/regtested x86_64-linux together with the ipa-modref change,
> OK?

OK.

Thanks,
Richard.

> Honza
> 
> 	* tree-ssa-alias.c (ao_ref_init_from_ptr_and_range): Break out from ...
> 	(ao_ref_init_from_ptr_and_size): ... here.
> diff --git a/gcc/tree-ssa-alias.c b/gcc/tree-ssa-alias.c
> index fe390d4ffbe..1b83749f989 100644
> --- a/gcc/tree-ssa-alias.c
> +++ b/gcc/tree-ssa-alias.c
> @@ -735,14 +737,21 @@ ao_ref_alias_set (ao_ref *ref)
>  }
>  
>  /* Init an alias-oracle reference representation from a gimple pointer
> -   PTR and a gimple size SIZE in bytes.  If SIZE is NULL_TREE then the
> -   size is assumed to be unknown.  The access is assumed to be only
> -   to or after of the pointer target, not before it.  */
> +   PTR a range specified by OFFSET, SIZE and MAX_SIZE under the assumption
> +   that RANGE_KNOWN is set.
>  
> -void
> -ao_ref_init_from_ptr_and_size (ao_ref *ref, tree ptr, tree size)
> +   The access is assumed to be only to or after of the pointer target adjusted
> +   by the offset, not before it (even in the case RANGE_KNOWN is false).  */
> +
> +static void
> +ao_ref_init_from_ptr_and_range (ao_ref *ref, tree ptr,
> +				bool range_known,
> +				poly_int64 offset,
> +				poly_int64 size,
> +				poly_int64 max_size)
>  {
> -  poly_int64 t, size_hwi, extra_offset = 0;
> +  poly_int64 t, extra_offset = 0;
> +
>    ref->ref = NULL_TREE;
>    if (TREE_CODE (ptr) == SSA_NAME)
>      {
> @@ -766,7 +775,7 @@ ao_ref_init_from_ptr_and_size (ao_ref *ref, tree ptr, tree size)
>  	ref->offset = BITS_PER_UNIT * t;
>        else
>  	{
> -	  size = NULL_TREE;
> +	  range_known = false;
>  	  ref->offset = 0;
>  	  ref->base = get_base_address (TREE_OPERAND (ptr, 0));
>  	}
> @@ -778,11 +787,12 @@ ao_ref_init_from_ptr_and_size (ao_ref *ref, tree ptr, tree size)
>  			  ptr, null_pointer_node);
>        ref->offset = 0;
>      }
> -  ref->offset += extra_offset;
> -  if (size
> -      && poly_int_tree_p (size, &size_hwi)
> -      && coeffs_in_range_p (size_hwi, 0, HOST_WIDE_INT_MAX / BITS_PER_UNIT))
> -    ref->max_size = ref->size = size_hwi * BITS_PER_UNIT;
> +  ref->offset += extra_offset + offset;
> +  if (range_known)
> +    {
> +      ref->max_size = max_size;
> +      ref->size = size;
> +    }
>    else
>      ref->max_size = ref->size = -1;
>    ref->ref_alias_set = 0;
> @@ -790,6 +800,26 @@ ao_ref_init_from_ptr_and_size (ao_ref *ref, tree ptr, tree size)
>    ref->volatile_p = false;
>  }
>  
> +/* Init an alias-oracle reference representation from a gimple pointer
> +   PTR and a gimple size SIZE in bytes.  If SIZE is NULL_TREE then the
> +   size is assumed to be unknown.  The access is assumed to be only
> +   to or after of the pointer target, not before it.  */
> +
> +void
> +ao_ref_init_from_ptr_and_size (ao_ref *ref, tree ptr, tree size)
> +{
> +  poly_int64 size_hwi;
> +  if (size
> +      && poly_int_tree_p (size, &size_hwi)
> +      && coeffs_in_range_p (size_hwi, 0, HOST_WIDE_INT_MAX / BITS_PER_UNIT))
> +    {
> +      size_hwi = size_hwi * BITS_PER_UNIT;
> +      ao_ref_init_from_ptr_and_range (ref, ptr, true, 0, size_hwi, size_hwi);
> +    }
> +  else
> +    ao_ref_init_from_ptr_and_range (ref, ptr, false, 0, -1, -1);
> +}
> +
>  /* S1 and S2 are TYPE_SIZE or DECL_SIZE.  Compare them:
>     Return -1 if S1 < S2
>     Return 1 if S1 > S2
>