On Mon, Jun 27, 2011 at 7:17 PM, Kai Tietz <kti...@redhat.com> wrote:
> Ups, missed to update patch.
You still modify the
/* If the first argument is an SSA name that is itself a result of a
typecast of an ADDR_EXPR to an integer, feed the ADDR_EXPR to the
folder rather than the ssa name. */
block. Please merge the constant handling with the
CONVERT_EXPR_CODE_P path instead. The above block is purely
legacy and should probably be entirely dropped.
Richard.
> Kai
>
> ----- Original Message -----
> From: "Kai Tietz" <kti...@redhat.com>
> To: "Richard Guenther" <richard.guent...@gmail.com>
> Cc: gcc-patches@gcc.gnu.org
> Sent: Monday, June 27, 2011 7:04:04 PM
> Subject: Re: [patch tree-optimization]: Try to sink type-casts for binary
> and/or/xor operations
>
> Hi,
>
> so I modified patch to use int_fits_type_p() for integer CST checking. Well,
> this approach is - as discussed on IRC suboptimal - as my intial approach was
> for and-operations with precision type > precision type-x and unsigned type-x
> for constant values bigger then (type-x)~0.
> But well, those we miss now by int_fits_type_p() approach, too. And also we
> miss now the cases for that type is signed and type-x is unsigned with same
> precision.
>
> Anyway ... here is the updated patch
>
> Regards,
> Kai
>
> ----- Original Message -----
> From: "Richard Guenther" <richard.guent...@gmail.com>
> To: "Kai Tietz" <kti...@redhat.com>
> Cc: gcc-patches@gcc.gnu.org
> Sent: Monday, June 27, 2011 4:08:41 PM
> Subject: Re: [patch tree-optimization]: Try to sink type-casts for binary
> and/or/xor operations
>
> On Mon, Jun 27, 2011 at 3:46 PM, Kai Tietz <kti...@redhat.com> wrote:
>> Hello,
>>
>> this patch sink type conversions in forward-propagate for the following
>> patterns:
>> - ((type) X) op ((type) Y): If X and Y have compatible types.
>> - ((type) X) op CST: If the conversion of (type) ((type-x) CST) == CST and X
>> has integral type.
>> - CST op ((type) X): If the conversion of (type) ((type-x) CST) == CST and X
>> has integral type.
>
> See IRC comments.
>
>> Additionally it fixes another issue shown by this type-sinking in bswap
>> detection. The bswap pattern matching algorithm goes for the first hit, and
>> not tries to seek for best hit. So we search here two times. First for di
>> case (if present) and then for si mode case.
>
> Please split this piece out. I suppose either walking over stmts backwards
> or simply handling __builtin_bswap in find_bswap_1 would be a better
> fix than yours.
>
> Richard.
>
>> ChangeLog
>>
>> 2011-06-27 Kai Tietz <kti...@redhat.com>
>>
>> * tree-ssa-forwprop.c (simplify_bitwise_binary): Improve
>> type sinking.
>> * tree-ssa-math-opts.c (execute_optimize_bswap): Separate
>> search for di/si mode patterns for finding widest match.
>>
>> Bootstrapped and regression tested for x86_64-pc-linux-gnu. Ok for apply?
>>
>> Regards,
>> Kai
>>
>
