Re: [PATCH 2/6] Avoid redundant operations in `fortran_array_walker'

[Andrew Burgess <aburgess@redhat.com>]

* Maciej W. Rozycki <macro@embecosm.com> [2021-12-11 11:47:14 +0000]:

> Move inner dimension's element type determination outside the respective 
> loops in `fortran_array_walker'.  The operation is exactly the same with 
> each iteration, so there is no point in redoing it for each element and 
> while a smart compiler might be able to move it outside the loop it is 
> regardless a bad coding style.  No functional change.

LGTM.

Thanks,
Andrew


> ---
>  gdb/f-array-walker.h |    7 ++++---
>  1 file changed, 4 insertions(+), 3 deletions(-)
> 
> gdb-fortran-array-walker-walk-type.diff
> Index: src/gdb/f-array-walker.h
> ===================================================================
> --- src.orig/gdb/f-array-walker.h
> +++ src/gdb/f-array-walker.h
> @@ -208,6 +208,8 @@ class fortran_array_walker
>  
>      if (nss != m_ndimensions)
>        {
> +	struct type *subarray_type = TYPE_TARGET_TYPE (check_typedef (type));
> +
>  	/* For dimensions other than the inner most, walk each element and
>  	   recurse while peeling off one more dimension of the array.  */
>  	for (LONGEST i = lowerbound;
> @@ -218,13 +220,13 @@ class fortran_array_walker
>  	    LONGEST new_offset = offset + calc.index_offset (i);
>  
>  	    /* Now print the lower dimension.  */
> -	    struct type *subarray_type
> -	      = TYPE_TARGET_TYPE (check_typedef (type));
>  	    walk_1 (nss + 1, subarray_type, new_offset, (i == upperbound));
>  	  }
>        }
>      else
>        {
> +	struct type *elt_type = check_typedef (TYPE_TARGET_TYPE (type));
> +
>  	/* For the inner most dimension of the array, process each element
>  	   within this dimension.  */
>  	for (LONGEST i = lowerbound;
> @@ -233,7 +235,6 @@ class fortran_array_walker
>  	  {
>  	    LONGEST elt_off = offset + calc.index_offset (i);
>  
> -	    struct type *elt_type = check_typedef (TYPE_TARGET_TYPE (type));
>  	    if (is_dynamic_type (elt_type))
>  	      {
>  		CORE_ADDR e_address = m_address + elt_off;
>