diff options
Diffstat (limited to 'gcc/testsuite/gcc.dg/tree-ssa/ldist-1.c')
| -rw-r--r-- | gcc/testsuite/gcc.dg/tree-ssa/ldist-1.c | 38 |
1 files changed, 38 insertions, 0 deletions
diff --git a/gcc/testsuite/gcc.dg/tree-ssa/ldist-1.c b/gcc/testsuite/gcc.dg/tree-ssa/ldist-1.c new file mode 100644 index 000000000..43c104665 --- /dev/null +++ b/gcc/testsuite/gcc.dg/tree-ssa/ldist-1.c @@ -0,0 +1,38 @@ +/* { dg-do compile } */ +/* { dg-options "-O2 -ftree-loop-distribution -fdump-tree-ldist-all" } */ + +void foo (int * __restrict__ ia, + int * __restrict__ ib, + int * __restrict__ oxa, + int * __restrict__ oxb, + int * __restrict__ oya, + int * __restrict__ oyb) +{ + int i; + long int mya[52]; + long int myb[52]; + + for (i=0; i < 52; i++) + { + mya[i] = ia[i] * oxa[i] + ib[i] * oxb[i]; + myb[i] = -ia[i] * oxb[i] + ib[i] * oxa[i]; + oya[i] = mya[i] >> 10; + oyb[i] = myb[i] >> 10; + } + + /* This loop was distributed, but it is not anymore due to the cost + model changes: the result of a distribution would look like this: + + | for (i=0; i < 52; i++) + | oya[i] = ia[i] * oxa[i] + ib[i] * oxb[i] >> 10; + | + | for (i=0; i < 52; i++) + | oyb[i] = -ia[i] * oxb[i] + ib[i] * oxa[i] >> 10; + + and in this the array IA is read in both tasks. For maximizing + the cache reuse, ldist does not distributes this loop anymore. + */ +} + +/* { dg-final { scan-tree-dump-times "distributed: split to 2 loops" 0 "ldist" } } */ +/* { dg-final { cleanup-tree-dump "ldist" } } */ |