Re: Fix PR middle-end/57370

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

On Fri, Aug 30, 2013 at 2:30 AM, Easwaran Raman <eraman@google.com> wrote:
> Richard,
> Do you want me to commit everything but the  insert_stmt_after hunk
> now?

Yes.

> There are more similar failures reported in
> http://gcc.gnu.org/bugzilla/show_bug.cgi?id=57393 and I have attached
> the updated patch there. Shall I send that for review? Apart from the
> debug statement issue, almost all the bugs are due to dependence
> violation because certain newly inserted statements do not have the
> right UID. Instead of trying to catch all of them, will it be better
> if I check if the stmt has a proper uid (non-zero if it is not the
> first stmt) and assign a sensible value at the point where it is used
> (find_insert_point and appears_later_in_bb) instead of where the stmt
> is created? I think that would be less brittle.

In the end all this placement stuff should be reverted and done as
post-processing after reassoc is finished.  You can remember the
inserted stmts that are candidates for moving (just set a pass-local
flag on them) and assign UIDs for the whole function after all stmts
are inserted.

Richard.


> - Easwaran
>
>
>
> On Tue, Aug 27, 2013 at 3:35 AM, Richard Biener
> <richard.guenther@gmail.com> wrote:
>> On Thu, Aug 1, 2013 at 1:34 AM, Easwaran Raman <eraman@google.com> wrote:
>>> I have a new patch that supersedes this. The new patch also fixes PR
>>> tree-optimization/57393 and PR tree-optimization/58011. Bootstraps and
>>> no test regression on x86_64/linux. Ok for trunk?
>>>
>>> 2013-07-31  Easwaran Raman  <eraman@google.com>
>>>
>>>     PR middle-end/57370
>>>     * tree-ssa-reassoc.c (build_and_add_sum): Fix UID assignment and reset
>>>     of debug statements that cause inconsistent IR.
>>
>> Missing ChangeLog entry for the insert_stmt_after hunk which I do not like
>> at all.  The other hunks are ok, but we need to work harder to preserve
>> debug stmts - simply removing all is not going to fly.
>>
>> Richard.
>>
>>>
>>> testsuite/ChangeLog:
>>> 2013-07-31  Easwaran Raman  <eraman@google.com>
>>>
>>>     PR middle-end/57370
>>>     PR tree-optimization/57393
>>>     PR tree-optimization/58011
>>>     * gfortran.dg/reassoc_12.f90: New testcase.
>>>     * gcc.dg/tree-ssa/reassoc-31.c: New testcase.
>>>     * gcc.dg/tree-ssa/reassoc-31.c: New testcase.
>>>
>>>
>>> On Fri, Jul 12, 2013 at 7:57 AM, Easwaran Raman <eraman@google.com> wrote:
>>>> Ping.
>>>>
>>>> On Thu, Jun 27, 2013 at 10:15 AM, Easwaran Raman <eraman@google.com> wrote:
>>>>> A newly generated statement in build_and_add_sum  function of
>>>>> tree-ssa-reassoc.c has to be assigned the UID of its adjacent
>>>>> statement. In one instance, it was assigned the wrong uid (of an
>>>>> earlier phi statement) which messed up the IR and caused the test
>>>>> program to hang. Bootstraps and no test regressions on x86_64/linux.
>>>>> Ok for trunk?
>>>>>
>>>>> Thanks,
>>>>> Easwaran
>>>>>
>>>>>
>>>>> 2013-06-27  Easwaran Raman  <eraman@google.com>
>>>>>
>>>>>         PR middle-end/57370
>>>>>         * tree-ssa-reassoc.c (build_and_add_sum): Do not use the UID of a phi
>>>>>         node for a non-phi gimple statement.
>>>>>
>>>>> testsuite/ChangeLog:
>>>>> 2013-06-27  Easwaran Raman  <eraman@google.com>
>>>>>
>>>>>         PR middle-end/57370
>>>>>         * gfortran.dg/reassoc_12.f90: New testcase.
>>>>>
>>>>>
>>>>> Index: gcc/testsuite/gfortran.dg/reassoc_12.f90
>>>>> ===================================================================
>>>>> --- gcc/testsuite/gfortran.dg/reassoc_12.f90 (revision 0)
>>>>> +++ gcc/testsuite/gfortran.dg/reassoc_12.f90 (revision 0)
>>>>> @@ -0,0 +1,74 @@
>>>>> +! { dg-do compile }
>>>>> +! { dg-options "-O2 -ffast-math" }
>>>>> +! PR middle-end/57370
>>>>> +
>>>>> + SUBROUTINE xb88_lr_adiabatic_lda_calc(e_ndrho_ndrho_ndrho, &
>>>>> +                                       grad_deriv,npoints, sx)
>>>>> +    IMPLICIT REAL*8 (t)
>>>>> +    INTEGER, PARAMETER :: dp=8
>>>>> +    REAL(kind=dp), DIMENSION(1:npoints) :: e_ndrho_ndrho_ndrho, &
>>>>> +                                           e_ndrho_ndrho_rho
>>>>> +      DO ii=1,npoints
>>>>> +          IF( grad_deriv >= 2 .OR. grad_deriv == -2 ) THEN
>>>>> +            t1425 = t233 * t557
>>>>> +            t1429 = beta * t225
>>>>> +            t1622 = t327 * t1621
>>>>> +            t1626 = t327 * t1625
>>>>> +            t1632 = t327 * t1631
>>>>> +            t1685 = t105 * t1684
>>>>> +            t2057 = t1636 + t8 * (t2635 + t3288)
>>>>> +          END IF
>>>>> +          IF( grad_deriv >= 3 .OR. grad_deriv == -3 ) THEN
>>>>> +            t5469 = t5440 - t5443 - t5446 - t5449 - &
>>>>> +                    t5451 - t5454 - t5456 + t5459  - &
>>>>> +                    t5462 + t5466 - t5468
>>>>> +            t5478 = 0.240e2_dp * t1616 * t973 * t645 * t1425
>>>>> +            t5489 = 0.1600000000e2_dp * t1429 * t1658
>>>>> +            t5531 = 0.160e2_dp * t112 * t1626
>>>>> +            t5533 = 0.160e2_dp * t112 * t1632
>>>>> +            t5537 = 0.160e2_dp * t112 * t1622
>>>>> +            t5541 = t5472 - t5478 - t5523 + t5525 + &
>>>>> +                    t5531 + t5533 + t5535 + t5537 + &
>>>>> +                    t5540
>>>>> +            t5565 = t112 * t1685
>>>>> +            t5575 = t5545 - t5548 + t5551 + t5553 - &
>>>>> +                    t5558 + t5560 - t5562 + t5564 - &
>>>>> +                    0.80e1_dp * t5565 + t5568 + t5572 + &
>>>>> +                    t5574
>>>>> +            t5611 = t5579 - t5585 + t5590 - t5595 + &
>>>>> +                    t5597 - t5602 + t5604 + t5607 + &
>>>>> +                    t5610
>>>>> +            t5613 = t5469 + t5541 + t5575 + t5611
>>>>> +            t6223 = t6189 - &
>>>>> +                    0.3333333336e0_dp  * t83 * t84 * t5613 + &
>>>>> +                    t6222
>>>>> +            t6227 = - t8 * (t5305 + t6223)
>>>>> +            e_ndrho_ndrho_rho(ii) = e_ndrho_ndrho_rho(ii) + &
>>>>> +                     t6227 * sx
>>>>> +            t6352 = t5440 - t5443 - t5446 - t5449 - &
>>>>> +                    t5451 - t5454 + &
>>>>> +                    0.40e1_dp * t102  * t327 * t2057 * t557 - &
>>>>> +                    t5456 + t5459 - t5462 + t5466 - &
>>>>> +                    t5468
>>>>> +            t6363 = t5480 - t5489 + &
>>>>> +                    0.9600000000e2_dp  * t1054 * t640 * t3679
>>>>> +            t6367 = t5472 - t5474 - t5478 - t5523 + &
>>>>> +                    t5525 + t5531 + t5533 + t5535 + &
>>>>> +                    t5537 - 0.20e1_dp * t102 * t105 * t6363 + &
>>>>> +                    t5540
>>>>> +            t6370 = t5545 - t5548 + t5551 + t5553 - &
>>>>> +                    t5558 + t5560 - t5562 + t5564  - &
>>>>> +                    0.40e1_dp * t5565 + &
>>>>> +                    t5568 + t5572 + t5574
>>>>> +            t6373 = t5579 - t5585 + t5590 - t5595 + &
>>>>> +                    t5597 - t5602 + t5604 + t5607 + &
>>>>> +                    t5610
>>>>> +            t6375 = t6352 + t6367 + t6370 + t6373
>>>>> +            t6380 = - 0.3333333336e0_dp * t83 * t84 * t6375 + t5701
>>>>> +            t6669 = -t4704 - t8 * (t6344 + t6380 + t6665)
>>>>> +            e_ndrho_ndrho_ndrho(ii) = e_ndrho_ndrho_ndrho(ii) + &
>>>>> +                     t6669 * sx
>>>>> +          END IF
>>>>> +      END DO
>>>>> +  END SUBROUTINE xb88_lr_adiabatic_lda_calc
>>>>> +
>>>>> Index: gcc/tree-ssa-reassoc.c
>>>>> ===================================================================
>>>>> --- gcc/tree-ssa-reassoc.c        (revision 200429)
>>>>> +++ gcc/tree-ssa-reassoc.c        (working copy)
>>>>> @@ -1207,7 +1207,7 @@ build_and_add_sum (tree type, tree op1, tree op2,
>>>>>        if (gimple_code (op1def) == GIMPLE_PHI)
>>>>>          {
>>>>>            gsi = gsi_after_labels (gimple_bb (op1def));
>>>>> -           gimple_set_uid (sum, gimple_uid (op1def));
>>>>> +          gimple_set_uid (sum, gimple_uid (gsi_stmt (gsi)));
>>>>>            gsi_insert_before (&gsi, sum, GSI_NEW_STMT);
>>>>>          }
>>>>>        else