[PATCH 8/9] ipa-sra: Make scan_expr_access bail out on uninteresting expressions

[Jan Hubicka]

> Hi,
> 
> I'm re-posting patches which I have posted at the end of stage 1 but
> which have not passed review yet.
> 
> 8<--------------------------------------------------------------------
> 
> I have noticed that scan_expr_access passes all the expressions it
> gets to get_ref_base_and_extent even when we are really only
> interested in memory accesses.  So bail out when the expression is
> something clearly uninteresting.
> 
> Bootstrapped and tested individually when I originally posted it and
> now bootstrapped and LTO-bootstrapped and tested as part of the whole
> series.  OK for master?
> 
> 
> gcc/ChangeLog:
> 
> 2021-12-14  Martin Jambor  <mjambor@suse.cz>
> 
> 	* ipa-sra.c (scan_expr_access): Bail out early if expr is something we
> 	clearly do not need to pass to get_ref_base_and_extent.
> ---
>  gcc/ipa-sra.cc | 5 +++++
>  1 file changed, 5 insertions(+)
> 
> diff --git a/gcc/ipa-sra.cc b/gcc/ipa-sra.cc
> index 93fceeafc73..3646d71468c 100644
> --- a/gcc/ipa-sra.cc
> +++ b/gcc/ipa-sra.cc
> @@ -1748,6 +1748,11 @@ scan_expr_access (tree expr, gimple *stmt, isra_scan_context ctx,
>        || TREE_CODE (expr) == REALPART_EXPR)
>      expr = TREE_OPERAND (expr, 0);
>  
> +  if (!handled_component_p (expr)
> +      && !DECL_P (expr)
> +      && TREE_CODE (expr) != MEM_REF)
> +    return;
Is this needed because get_ref_base_and_extend crashes if given SSA_NAME
or something else or is it just optimization?
Perhaps Richi will know if there is better test for this.

Honza
> +
>    base = get_ref_base_and_extent (expr, &poffset, &psize, &pmax_size, &reverse);
>  
>    if (TREE_CODE (base) == MEM_REF)
> -- 
> 2.38.1
>