Re: Add VIEW_CONVERT_EXPR to operand_equal_p

[Richard Biener <richard.guenther@gmail.com>]

On Wed, Oct 21, 2015 at 6:05 AM, Jan Hubicka <hubicka@ucw.cz> wrote:
> Hi,
> here is updated patch that applies changes suggested by Richard. I apologize
> for the delay - the testing failed several times on gcc10.fsffrance.org for me
> for out-of-memory errors (which are unrelated) and I was on the travel.
>
> Bootstrapped/regtested x86_64-linux, OK?

Ok.

Thanks,
Richard.

>         * tree.c (verify_type): Verify that TYPE_MODE match
>         between TYPE_CANONICAL and type.
>         * expr.c (store_expr_with_bounds): Revert my previous change.
>         * expmed.c (store_bit_field_1): Revert prevoius change.
>         * gimple-expr.c (useless_type_conversion_p): Require TYPE_MODE
>         to match for all types.
>
> Index: tree.c
> ===================================================================
> --- tree.c      (revision 228933)
> +++ tree.c      (working copy)
> @@ -13344,6 +13344,14 @@ verify_type (const_tree t)
>        error_found = true;
>      }
>
> +  if (COMPLETE_TYPE_P (t) && TYPE_CANONICAL (t)
> +      && TYPE_MODE (t) != TYPE_MODE (TYPE_CANONICAL (t)))
> +    {
> +      error ("TYPE_MODE of TYPE_CANONICAL is not compatible");
> +      debug_tree (ct);
> +      error_found = true;
> +    }
> +
>
>    /* Check various uses of TYPE_MINVAL.  */
>    if (RECORD_OR_UNION_TYPE_P (t))
> Index: expr.c
> ===================================================================
> --- expr.c      (revision 228933)
> +++ expr.c      (working copy)
> @@ -5425,14 +5425,6 @@ store_expr_with_bounds (tree exp, rtx ta
>      temp = convert_modes (GET_MODE (target), TYPE_MODE (TREE_TYPE (exp)),
>                           temp, TYPE_UNSIGNED (TREE_TYPE (exp)));
>
> -  /* We allow move between structures of same size but different mode.
> -     If source is in memory and the mode differs, simply change the memory.  */
> -  if (GET_MODE (temp) == BLKmode && GET_MODE (target) != BLKmode)
> -    {
> -      gcc_assert (MEM_P (temp));
> -      temp = adjust_address_nv (temp, GET_MODE (target), 0);
> -    }
> -
>    /* If value was not generated in the target, store it there.
>       Convert the value to TARGET's type first if necessary and emit the
>       pending incrementations that have been queued when expanding EXP.
> Index: expmed.c
> ===================================================================
> --- expmed.c    (revision 228933)
> +++ expmed.c    (working copy)
> @@ -757,14 +757,6 @@ store_bit_field_1 (rtx str_rtx, unsigned
>        }
>    }
>
> -  /* We allow move between structures of same size but different mode.
> -     If source is in memory and the mode differs, simply change the memory.  */
> -  if (GET_MODE (value) == BLKmode && GET_MODE (op0) != BLKmode)
> -    {
> -      gcc_assert (MEM_P (value));
> -      value = adjust_address_nv (value, GET_MODE (op0), 0);
> -    }
> -
>    /* Storing an lsb-aligned field in a register
>       can be done with a movstrict instruction.  */
>
> Index: gimple-expr.c
> ===================================================================
> --- gimple-expr.c       (revision 228933)
> +++ gimple-expr.c       (working copy)
> @@ -87,10 +87,8 @@ useless_type_conversion_p (tree outer_ty
>    if (inner_type == outer_type)
>      return true;
>
> -  /* Changes in machine mode are never useless conversions unless we
> -     deal with aggregate types in which case we defer to later checks.  */
> -  if (TYPE_MODE (inner_type) != TYPE_MODE (outer_type)
> -      && !AGGREGATE_TYPE_P (inner_type))
> +  /* Changes in machine mode are never useless conversions unless.  */
> +  if (TYPE_MODE (inner_type) != TYPE_MODE (outer_type))
>      return false;
>
>    /* If both the inner and outer types are integral types, then the
> @@ -270,10 +268,9 @@ useless_type_conversion_p (tree outer_ty
>       use the types in move operations.  */
>    else if (AGGREGATE_TYPE_P (inner_type)
>            && TREE_CODE (inner_type) == TREE_CODE (outer_type))
> -    return (!TYPE_SIZE (outer_type)
> -           || (TYPE_SIZE (inner_type)
> -               && operand_equal_p (TYPE_SIZE (inner_type),
> -                                   TYPE_SIZE (outer_type), 0)));
> +    return (TYPE_MODE (outer_type) != BLKmode
> +           || operand_equal_p (TYPE_SIZE (inner_type),
> +                               TYPE_SIZE (outer_type), 0));
>
>    else if (TREE_CODE (inner_type) == OFFSET_TYPE
>            && TREE_CODE (outer_type) == OFFSET_TYPE)