Re: [Patch] PR56064: Fold VIEW_CONVERT_EXPR with FIXED_CST

[Richard Biener <richard dot guenther at gmail dot com>]

On Mon, Jan 21, 2013 at 2:28 PM, Georg-Johann Lay <avr@gjlay.de> wrote:
> This is tentative patch as discussed in
>
> http://gcc.gnu.org/ml/gcc/2013-01/msg00187.html
>
> fold-const.c gets 2 new function native_encode_fixed and
> native_interpret_fixed.  Code common with the integer case is factored out and
> moved to the new constructor-like function double_int::from_buffer.
>
> The code bootstraps fine on x86-linux-gnu and I have test coverage from
> avr-unknown-none.
>
> Ok to apply?

Ok.

Thanks,
Richard.

> There are less intrusive solutions that only handle the int <-> fixed cases,
> for example fold-const.c:fold_view_convert_expr() could test for these cases
> and use double_int directly without serializing / deserializing through a
> memory buffer.
>
> Johann
>
>
>         PR tree-optimization/56064
>         * fixed-value.c (const_fixed_from_double_int): New function.
>         * fixed-value.h (const_fixed_from_double_int): New prototype.
>         * fold-const.c (native_interpret_fixed): New static function.
>         (native_interpret_expr) <FIXED_POINT_TYPE>: Use it.
>         (can_native_interpret_type_p) <FIXED_POINT_TYPE>: Return true.
>         (native_encode_fixed): New static function.
>         (native_encode_expr) <FIXED_CST>: Use it.
>         (native_interpret_int): Move double_int worker code to...
>         * double-int.c (double_int::from_buffer): ...this new static method.
>         * double-int.h (double_int::from_buffer): Prototype it.
>
> testsuite/
>         PR tree-optimization/56064
>         * gcc.dg/fixed-point/view-convert.c: New test.