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| author | Richard Biener <rguenther@suse.de> | 2024-09-19 14:58:18 +0200 |
|---|---|---|
| committer | Richard Biener <rguenth@gcc.gnu.org> | 2024-09-19 16:26:28 +0200 |
| commit | 5b5a36b122e1205449f1512bf39521b669e713ef (patch) | |
| tree | d0e5392098ece9d8c7f47ba7bd8e2aba2959be97 | |
| parent | 77bd23a3e247555ba427d01af8e5713934be8d5b (diff) | |
| download | gcc-5b5a36b122e1205449f1512bf39521b669e713ef.zip gcc-5b5a36b122e1205449f1512bf39521b669e713ef.tar.gz gcc-5b5a36b122e1205449f1512bf39521b669e713ef.tar.bz2 | |
tree-optimization/116768 - wrong dependence analysis
The following reverts a bogus fix done for PR101009 and instead makes
sure we get into the same_access_functions () case when computing
the distance vector for g[1] and g[1] where the constants ended up
having different types. The generic code doesn't seem to handle
loop invariant dependences. The special case gets us both
( 0 ) and ( 1 ) as distance vectors while formerly we got ( 1 ),
which the PR101009 fix changed to ( 0 ) with bad effects on other
cases as shown in this PR.
PR tree-optimization/116768
* tree-data-ref.cc (build_classic_dist_vector_1): Revert
PR101009 change.
* tree-chrec.cc (eq_evolutions_p): Make sure (sizetype)1
and (int)1 compare equal.
* gcc.dg/torture/pr116768.c: New testcase.
| -rw-r--r-- | gcc/testsuite/gcc.dg/torture/pr116768.c | 32 | ||||
| -rw-r--r-- | gcc/tree-chrec.cc | 4 | ||||
| -rw-r--r-- | gcc/tree-data-ref.cc | 2 |
3 files changed, 34 insertions, 4 deletions
diff --git a/gcc/testsuite/gcc.dg/torture/pr116768.c b/gcc/testsuite/gcc.dg/torture/pr116768.c new file mode 100644 index 0000000..57b5d00 --- /dev/null +++ b/gcc/testsuite/gcc.dg/torture/pr116768.c @@ -0,0 +1,32 @@ +/* { dg-do run } */ + +#define numwords 2 + +typedef struct { + unsigned words[numwords]; +} Child; + +typedef struct { + Child child; +} Parent; + +Parent my_or(Parent x, const Parent *y) { + const Child *y_child = &y->child; + for (int i = 0; i < numwords; i++) { + x.child.words[i] |= y_child->words[i]; + } + return x; +} + +int main() { + Parent bs[4]; + __builtin_memset(bs, 0, sizeof(bs)); + + bs[0].child.words[0] = 1; + for (int i = 1; i <= 3; i++) { + bs[i] = my_or(bs[i], &bs[i - 1]); + } + if (bs[2].child.words[0] != 1) + __builtin_abort (); + return 0; +} diff --git a/gcc/tree-chrec.cc b/gcc/tree-chrec.cc index 8b7982a..9b27207 100644 --- a/gcc/tree-chrec.cc +++ b/gcc/tree-chrec.cc @@ -1716,7 +1716,7 @@ eq_evolutions_p (const_tree chrec0, const_tree chrec1) || TREE_CODE (chrec0) != TREE_CODE (chrec1)) return false; - if (chrec0 == chrec1) + if (operand_equal_p (chrec0, chrec1, 0)) return true; if (! types_compatible_p (TREE_TYPE (chrec0), TREE_TYPE (chrec1))) @@ -1743,7 +1743,7 @@ eq_evolutions_p (const_tree chrec0, const_tree chrec1) TREE_OPERAND (chrec1, 0)); default: - return operand_equal_p (chrec0, chrec1, 0); + return false; } } diff --git a/gcc/tree-data-ref.cc b/gcc/tree-data-ref.cc index 0f173e8..de234c6 100644 --- a/gcc/tree-data-ref.cc +++ b/gcc/tree-data-ref.cc @@ -5223,8 +5223,6 @@ build_classic_dist_vector_1 (struct data_dependence_relation *ddr, non_affine_dependence_relation (ddr); return false; } - else - *init_b = true; } return true; |