tree-optimization/101173 - fix interchange dependence checking
This adjusts the loop interchange dependence checking to disallow an outer loop dependence distance of zero. 2021-06-23 Richard Biener <rguenther@suse.de> PR tree-optimization/101173 * gimple-loop-interchange.cc (tree_loop_interchange::valid_data_dependences): Disallow outer loop dependence distance of zero. * gcc.dg/torture/pr101173.c: New testcase.
This commit is contained in:
parent
3f1a08d9d7
commit
0ad9d88a3d
|
@ -1043,8 +1043,8 @@ tree_loop_interchange::valid_data_dependences (unsigned i_idx, unsigned o_idx,
|
|||
continue;
|
||||
|
||||
/* Be conservative, skip case if either direction at i_idx/o_idx
|
||||
levels is not '=' or '<'. */
|
||||
if (dist_vect[i_idx] < 0 || dist_vect[o_idx] < 0)
|
||||
levels is not '=' (for the inner loop) or '<'. */
|
||||
if (dist_vect[i_idx] < 0 || dist_vect[o_idx] <= 0)
|
||||
return false;
|
||||
}
|
||||
}
|
||||
|
|
|
@ -0,0 +1,18 @@
|
|||
/* { dg-do run } */
|
||||
/* { dg-additional-options "-floop-interchange" } */
|
||||
|
||||
int a[6][9];
|
||||
int main()
|
||||
{
|
||||
a[1][3] = 8;
|
||||
for (int b = 1; b <= 5; b++)
|
||||
for (int d = 0; d <= 5; d++)
|
||||
#pragma GCC unroll 0
|
||||
for (int c = 0; c <= 5; c++)
|
||||
a[b][c] = a[b][c + 2] & 216;
|
||||
for (int e = 0; e < 6; e++)
|
||||
for (int f = 0; f < 9; f++)
|
||||
if (a[e][f] != 0)
|
||||
__builtin_abort ();
|
||||
return 0;
|
||||
}
|
Loading…
Reference in New Issue