On Mon, May 2, 2016 at 11:18 AM, Marc Glisse <marc.gli...@inria.fr> wrote:
> On Mon, 2 May 2016, Richard Biener wrote:
>
>> On Sat, Apr 30, 2016 at 8:44 PM, Marc Glisse <marc.gli...@inria.fr> wrote:
>>>
>>> Hello,
>>>
>>> this case seemed to be missing in the various X cmp X transformations. It
>>> does not change the generated code in the testcase.
>>>
>>> The missing :c is rather trivial. I can commit it separately if you
>>> prefer.
>>
>>
>> I think it's not missing. Commutating the first one is enough to
>> eventually
>> make the @1s match up. I think you should get a diagnostic on a duplicate
>> pattern when adding another :c (hmm, no, it's indeed "different" patterns
>> but
>> still redundant).
>
>
> Let's see. The current pattern is
> (bitop (bit_and:c @0 @1) (bit_and @2 @1))
>
> This matches:
> (X & Y) ^ (Z & Y)
> (Y & X) ^ (Z & Y)
>
> If I have for instance (Y & X) ^ (Y & Z), I don't see how that is going to
> match, and indeed we don't simplify that.
Hmm, indeed. I might have wrongly ommitted some :c then in other places
as well. So the original patch is ok.
> On the other hand, if I have
> bit_ior instead of bit_xor, then we have another very similar transformation
> a 100 lines up in match.pd
>
> (for op (bit_and bit_ior)
> rop (bit_ior bit_and)
> (simplify
> (op (convert? (rop:c @0 @1)) (convert? (rop @0 @2)))
>
> That one also commutes only one, but starting from a different match. We
> should probably reorganize them a bit.
Yeah.
Richard.
>
>>> Bootstrap+regtest on powerpc64le-unknown-linux-gnu.
>>
>>
>> Ok for the new pattern.
>>
>> Thanks,
>> Richard.
>>
>>> 2016-05-02 Marc Glisse <marc.gli...@inria.fr>
>>>
>>> gcc/
>>> * match.pd ((A & B) OP (C & B)): Mark '&' as commutative.
>>> (X u< X, X u> X): New transformations
>>>
>>> gcc/testsuite/
>>> * gcc.dg/tree-ssa/unord.c: New testcase.
>>>
>>> --
>>> Marc Glisse
>>> Index: trunk/gcc/match.pd
>>> ===================================================================
>>> --- trunk/gcc/match.pd (revision 235654)
>>> +++ trunk/gcc/match.pd (working copy)
>>> @@ -783,21 +783,21 @@ DEFINE_INT_AND_FLOAT_ROUND_FN (RINT)
>>> @0)
>>> /* (~x | y) & x -> x & y */
>>> /* (~x & y) | x -> x | y */
>>> (simplify
>>> (bitop:c (rbitop:c (bit_not @0) @1) @0)
>>> (bitop @0 @1)))
>>>
>>> /* Simplify (A & B) OP0 (C & B) to (A OP0 C) & B. */
>>> (for bitop (bit_and bit_ior bit_xor)
>>> (simplify
>>> - (bitop (bit_and:c @0 @1) (bit_and @2 @1))
>>> + (bitop (bit_and:c @0 @1) (bit_and:c @2 @1))
>>> (bit_and (bitop @0 @2) @1)))
>>>
>>> /* (x | CST1) & CST2 -> (x & CST2) | (CST1 & CST2) */
>>> (simplify
>>> (bit_and (bit_ior @0 CONSTANT_CLASS_P@1) CONSTANT_CLASS_P@2)
>>> (bit_ior (bit_and @0 @2) (bit_and @1 @2)))
>>>
>>> /* Combine successive equal operations with constants. */
>>> (for bitop (bit_and bit_ior bit_xor)
>>> (simplify
>>> @@ -1914,20 +1914,24 @@ DEFINE_INT_AND_FLOAT_ROUND_FN (RINT)
>>> (simplify
>>> (cmp @0 @0)
>>> (if (cmp != NE_EXPR
>>> || ! FLOAT_TYPE_P (TREE_TYPE (@0))
>>> || ! HONOR_NANS (@0))
>>> { constant_boolean_node (false, type); })))
>>> (for cmp (unle unge uneq)
>>> (simplify
>>> (cmp @0 @0)
>>> { constant_boolean_node (true, type); }))
>>> +(for cmp (unlt ungt)
>>> + (simplify
>>> + (cmp @0 @0)
>>> + (unordered @0 @0)))
>>> (simplify
>>> (ltgt @0 @0)
>>> (if (!flag_trapping_math)
>>> { constant_boolean_node (false, type); }))
>>>
>>> /* Fold ~X op ~Y as Y op X. */
>>> (for cmp (simple_comparison)
>>> (simplify
>>> (cmp (bit_not@2 @0) (bit_not@3 @1))
>>> (if (single_use (@2) && single_use (@3))
>>> Index: trunk/gcc/testsuite/gcc.dg/tree-ssa/unord.c
>>> ===================================================================
>>> --- trunk/gcc/testsuite/gcc.dg/tree-ssa/unord.c (revision 0)
>>> +++ trunk/gcc/testsuite/gcc.dg/tree-ssa/unord.c (working copy)
>>> @@ -0,0 +1,7 @@
>>> +/* { dg-do compile } */
>>> +/* { dg-options "-O -fdump-tree-optimized" } */
>>> +
>>> +int f(double a){double b=a;return !__builtin_islessequal(a,b);}
>>> +int g(double a){double b=a;return !__builtin_isgreaterequal(a,b);}
>>> +
>>> +/* { dg-final { scan-tree-dump-times " unord " 2 "optimized" } } */
>
>
> --
> Marc Glisse
