[Bug tree-optimization/46886] [4.5/4.6 Regression] gfortran.dg/array_constructor_9.f90 FAILs with -ftree-parallelize-loops -fstrict-overflow -fno-tree-ch
http://gcc.gnu.org/bugzilla/show_bug.cgi?id=46886 --- Comment #5 from Sebastian Pop spop at gcc dot gnu.org 2011-02-14 04:19:03 UTC --- Patch: http://gcc.gnu.org/ml/gcc-patches/2011-02/msg00858.html
[Bug tree-optimization/46886] [4.5/4.6 Regression] gfortran.dg/array_constructor_9.f90 FAILs with -ftree-parallelize-loops -fstrict-overflow -fno-tree-ch
http://gcc.gnu.org/bugzilla/show_bug.cgi?id=46886 Richard Guenther rguenth at gcc dot gnu.org changed: What|Removed |Added Priority|P3 |P2
[Bug tree-optimization/46886] [4.5/4.6 Regression] gfortran.dg/array_constructor_9.f90 FAILs with -ftree-parallelize-loops -fstrict-overflow -fno-tree-ch
http://gcc.gnu.org/bugzilla/show_bug.cgi?id=46886 --- Comment #4 from sebpop at gmail dot com sebpop at gmail dot com 2011-02-04 20:30:46 UTC --- On Tue, Jan 18, 2011 at 11:00, jakub at gcc dot gnu.org gcc-bugzi...@gcc.gnu.org wrote: Seems one extra incorrect iteration is added after GOMP_parallel_end: That extra iteration is added by this call: /* Ensure that the exit condition is the first statement in the loop. */ transform_to_exit_first_loop (loop, reduction_list, nit); /* Moves the exit condition of LOOP to the beginning of its header, and duplicates the part of the last iteration that gets disabled to the exit of the loop. NIT is the number of iterations of the loop (used to initialize the variables in the duplicated part). TODO: the common case is that latch of the loop is empty and immediately follows the loop exit. In this case, it would be better not to copy the body of the loop, but only move the entry of the loop directly before the exit check and increase the number of iterations of the loop by one. This may need some additional preconditioning in case NIT = ~0. REDUCTION_LIST describes the reductions in LOOP. */ static void transform_to_exit_first_loop (struct loop *loop, htab_t reduction_list, tree nit)
[Bug tree-optimization/46886] [4.5/4.6 Regression] gfortran.dg/array_constructor_9.f90 FAILs with -ftree-parallelize-loops -fstrict-overflow -fno-tree-ch
http://gcc.gnu.org/bugzilla/show_bug.cgi?id=46886 --- Comment #2 from Jakub Jelinek jakub at gcc dot gnu.org 2011-02-04 07:11:53 UTC --- Sebastian, thanks for PR46194 fix, could you please also look at this one?
[Bug tree-optimization/46886] [4.5/4.6 Regression] gfortran.dg/array_constructor_9.f90 FAILs with -ftree-parallelize-loops -fstrict-overflow -fno-tree-ch
http://gcc.gnu.org/bugzilla/show_bug.cgi?id=46886 Sebastian Pop spop at gcc dot gnu.org changed: What|Removed |Added Status|UNCONFIRMED |ASSIGNED Last reconfirmed||2011.02.04 07:57:49 AssignedTo|unassigned at gcc dot |spop at gcc dot gnu.org |gnu.org | Ever Confirmed|0 |1 --- Comment #3 from Sebastian Pop spop at gcc dot gnu.org 2011-02-04 07:57:49 UTC --- Sure, I'll have a look.
[Bug tree-optimization/46886] [4.5/4.6 Regression] gfortran.dg/array_constructor_9.f90 FAILs with -ftree-parallelize-loops -fstrict-overflow -fno-tree-ch
http://gcc.gnu.org/bugzilla/show_bug.cgi?id=46886
Jakub Jelinek jakub at gcc dot gnu.org changed:
What|Removed |Added
CC||rakdver at gcc dot gnu.org,
||spop at gcc dot gnu.org
--- Comment #1 from Jakub Jelinek jakub at gcc dot gnu.org 2011-01-18
17:00:29 UTC ---
Seems one extra incorrect iteration is added after GOMP_parallel_end:
bb 16:
D.1592_69 = D.1591_183 * 4;
bb 17:
# D.1592_15 = PHI 0(15), D.1592_69(16)
D.1749_71 = (unnamed-unsigned:64) D.1592_15;
D.1750_72 = MAX_EXPR D.1749_71, 1;
D.1751_73 = __builtin_malloc (D.1750_72);
D.1594_74 = (void * restrict) D.1751_73;
D.1898_232 = (unnamed-unsigned:64) D.1591_183;
D.1899_233 = D.1591_183 = 0;
D.1900_234 = D.1898_232 199;
D.1901_235 = D.1899_233 D.1900_234;
if (D.1901_235 != 0)
goto bb 18;
else
goto bb 19;
bb 18:
.paral_data_store.64.D.1910 = D.1578_1;
.paral_data_store.64.D.1911 = D.1594_74;
.paral_data_store.64.D.1912 = D.1898_232;
__builtin_GOMP_parallel_start (build._loopfn.1, .paral_data_store.64, 2);
build._loopfn.1 (.paral_data_store.64);
__builtin_GOMP_parallel_end ();
ivtmp.60_247 = D.1898_232;
S.7_248 = (integer(kind=8)) ivtmp.60_247;
D.1755_249 = *D.1578_1[S.7_248];
MEM[(real(kind=4)[0:] *)D.1594_74][S.7_248] = D.1755_249;
S.7_251 = S.7_248 + 1;
ivtmp.60_252 = ivtmp.60_247 + 1;
S.7_248 is equal to the number of ints allocated, so stores after the end of
malloced area. The loop is initially:
loop_4 (header = 18, latch = 19, niter = , upper_bound = 9223372036854775808,
estimate = 9223372036854775808)
{
bb_18 (preds = {bb_17 bb_19 }, succs = {bb_20 bb_19 })
{
bb 18:
# S.7_7 = PHI 0(17), S.7_80(19)
# .MEM_152 = PHI .MEM_182(17), .MEM_185(19)
if (S.7_7 D.1586_64)
goto bb 20;
else
goto bb 19;
}
bb_19 (preds = {bb_18 }, succs = {bb_18 })
{
bb 19:
# VUSE .MEM_152
D.1755_79 = *D.1578_1[S.7_7];
# .MEM_185 = VDEF .MEM_152
MEM[(real(kind=4)[0:] *)D.1594_74][S.7_7] = D.1755_79;
S.7_80 = S.7_7 + 1;
goto bb 18;
}
}
and try_get_loop_niter computes niter-niter as (unnamed-unsigned:64)
D.1591_183. On:
__attribute__((noinline, noclone)) void
foo (int *__restrict__ p, int *__restrict__ q, int n)
{
int i;
for (i = 0; i n; i++)
p[i] = q[i];
}
int
main (void)
{
int *p = __builtin_calloc (1024, sizeof (int));
int *q = __builtin_calloc (1024, sizeof (int));
foo (p, q, 1024);
return 0;
}
try_get_loop_niter instead computes niter-niter as n - 1 (which is strange to
me), but then it works even with the extra iteration added after
GOMP_parallel_end (as that iteration is done with iv set to n - 1).
[Bug tree-optimization/46886] [4.5/4.6 Regression] gfortran.dg/array_constructor_9.f90 FAILs with -ftree-parallelize-loops -fstrict-overflow -fno-tree-ch
http://gcc.gnu.org/bugzilla/show_bug.cgi?id=46886 Jakub Jelinek jakub at gcc dot gnu.org changed: What|Removed |Added CC||jakub at gcc dot gnu.org Target Milestone|--- |4.5.3
