https://gcc.gnu.org/bugzilla/show_bug.cgi?id=61965
--- Comment #1 from Sabrina Souto <sabrinadfs at gmail dot com> ---
It happened again, now for this test: ../gcc/testsuite/gcc.dg/pr39794.c
Hera is the line executed:
/home/sabrina/gcc/objdir/gcc/xgcc -B/home/sabrina/gcc/objdir/gcc/
/home/sabrina/gcc/gcc-4.8.2/gcc/testsuite/gcc.dg/pr39794.c
-fno-diagnostics-show-caret -O2 -funroll-loops -fcheck-data-deps -o
./pr39794.c
Here is the testcode (../gcc/testsuite/gcc.dg/pr39794.c):
----------------------------------------------------------------------------
/* PR rtl-optimization/39794 */
/* { dg-do run } */
/* { dg-options "-O2 -funroll-loops" } */
extern void abort ();
void
foo (int *a, int n)
{
int i;
for (i = 0; i < n; i++)
{
a[i] *= 2;
a[i + 1] = a[i - 1] + a[i - 2];
}
}
int a[16];
int ref[16] = { 0, 1, 4, 2, 10, 12, 24, 44,
72, 136, 232, 416, 736, 1296, 2304, 2032 };
int
main ()
{
int i;
for (i = 0; i < 16; i++)
a[i] = i;
foo (a + 2, 16 - 3);
for (i = 0; i < 16; i++)
if (ref[i] != a[i])
abort ();
return 0;
}
----------------------------------------------------------------------------
Here is the output:
----------------------------------------------------------------------------
(Number of distance vectors differ: Banerjee has 1, Omega has 0.
Banerjee dist vectors:
1
Omega dist vectors:
data dependence relation:
(Data Dep:
#(Data Ref:
# bb: 5
# stmt: _9 = *_8;
# ref: *_8;
# base_object: *a_5(D);
# Access function 0: {0B, +, 4}_1
#)
#(Data Ref:
# bb: 5
# stmt: *_14 = _21;
# ref: *_14;
# base_object: *a_5(D);
# Access function 0: {4B, +, 4}_1
#)
access_fn_A: {0B, +, 4}_1
access_fn_B: {4B, +, 4}_1
(subscript
iterations_that_access_an_element_twice_in_A: [1 + 1 * x_1]
last_conflict: 2147483646
iterations_that_access_an_element_twice_in_B: [0 + 1 * x_1]
last_conflict: 2147483646
(Subscript distance: 1 ))
inner loop index: 0
loop nest: (1 )
)
)
/home/sabrina/gcc/gcc-4.8.2/gcc/testsuite/gcc.dg/pr39794.c: In function ‘foo’:
/home/sabrina/gcc/gcc-4.8.2/gcc/testsuite/gcc.dg/pr39794.c:8:1: internal
compiler error: in compute_affine_dependence, at tree-data-ref.c:4170
0xbcc0d2 compute_affine_dependence(data_dependence_relation*, loop*)
.././../gcc-4.8.2/gcc/tree-data-ref.c:4169
0xbce98d compute_all_dependences(vec<data_reference*, va_heap, vl_ptr>,
vec<data_dependence_relation*, va_heap, vl_ptr>*, vec<loop*, va_heap, vl_ptr>,
bool)
.././../gcc-4.8.2/gcc/tree-data-ref.c:4241
0xbcef83 compute_data_dependences_for_loop(loop*, bool, vec<loop*, va_heap,
vl_ptr>*, vec<data_reference*, va_heap, vl_ptr>*,
vec<data_dependence_relation*, va_heap, vl_ptr>*)
.././../gcc-4.8.2/gcc/tree-data-ref.c:4531
0xbcf18f analyze_all_data_dependences
.././../gcc-4.8.2/gcc/tree-data-ref.c:4639
0xbcf18f tree_check_data_deps()
.././../gcc-4.8.2/gcc/tree-data-ref.c:4687
0x8b62a7 check_data_deps
.././../gcc-4.8.2/gcc/tree-ssa-loop.c:330
Please submit a full bug report,
with preprocessed source if appropriate.
Please include the complete backtrace with any bug report.
See <http://gcc.gnu.org/bugs.html> for instructions.
sabrina@cioba:~/gcc$ clear
sabrina@cioba:~/gcc$ /home/sabrina/gcc/objdir/gcc/xgcc
-B/home/sabrina/gcc/objdir/gcc/
/home/sabrina/gcc/gcc-4.8.2/gcc/testsuite/gcc.dg/pr39794.c
-fno-diagnostics-show-caret -O2 -funroll-loops -fcheck-data-deps -o
./pr39794.c
(Number of distance vectors differ: Banerjee has 1, Omega has 0.
Banerjee dist vectors:
1
Omega dist vectors:
data dependence relation:
(Data Dep:
#(Data Ref:
# bb: 5
# stmt: _9 = *_8;
# ref: *_8;
# base_object: *a_5(D);
# Access function 0: {0B, +, 4}_1
#)
#(Data Ref:
# bb: 5
# stmt: *_14 = _21;
# ref: *_14;
# base_object: *a_5(D);
# Access function 0: {4B, +, 4}_1
#)
access_fn_A: {0B, +, 4}_1
access_fn_B: {4B, +, 4}_1
(subscript
iterations_that_access_an_element_twice_in_A: [1 + 1 * x_1]
last_conflict: 2147483646
iterations_that_access_an_element_twice_in_B: [0 + 1 * x_1]
last_conflict: 2147483646
(Subscript distance: 1 ))
inner loop index: 0
loop nest: (1 )
)
)
/home/sabrina/gcc/gcc-4.8.2/gcc/testsuite/gcc.dg/pr39794.c: In function ‘foo’:
/home/sabrina/gcc/gcc-4.8.2/gcc/testsuite/gcc.dg/pr39794.c:8:1: internal
compiler error: in compute_affine_dependence, at tree-data-ref.c:4170
0xbcc0d2 compute_affine_dependence(data_dependence_relation*, loop*)
.././../gcc-4.8.2/gcc/tree-data-ref.c:4169
0xbce98d compute_all_dependences(vec<data_reference*, va_heap, vl_ptr>,
vec<data_dependence_relation*, va_heap, vl_ptr>*, vec<loop*, va_heap, vl_ptr>,
bool)
.././../gcc-4.8.2/gcc/tree-data-ref.c:4241
0xbcef83 compute_data_dependences_for_loop(loop*, bool, vec<loop*, va_heap,
vl_ptr>*, vec<data_reference*, va_heap, vl_ptr>*,
vec<data_dependence_relation*, va_heap, vl_ptr>*)
.././../gcc-4.8.2/gcc/tree-data-ref.c:4531
0xbcf18f analyze_all_data_dependences
.././../gcc-4.8.2/gcc/tree-data-ref.c:4639
0xbcf18f tree_check_data_deps()
.././../gcc-4.8.2/gcc/tree-data-ref.c:4687
0x8b62a7 check_data_deps
.././../gcc-4.8.2/gcc/tree-ssa-loop.c:330
Please submit a full bug report,
with preprocessed source if appropriate.
Please include the complete backtrace with any bug report.
See <http://gcc.gnu.org/bugs.html> for instructions.
----------------------------------------------------------------------------
Someone could also confirm this one?
Thanks,
Sabrina de F. Souto.
