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[PR 82363] Fix thinko in SRA subaccess propagation
- From: Martin Jambor <mjambor at suse dot cz>
- To: GCC Patches <gcc-patches at gcc dot gnu dot org>
- Cc: Richard Biener <rguenther at suse dot de>
- Date: Mon, 2 Oct 2017 19:19:19 +0200
- Subject: [PR 82363] Fix thinko in SRA subaccess propagation
- Authentication-results: sourceware.org; auth=none
Hi,
the following fixes a thinko in propagate_subaccesses_across_link.
When we cannot copy over a tree of accesses of RHS to LHS because of
some conflict, we must mark the whole LHS access (sub-)tree as
potentially written, even when the RHS access describing this level is
not, because some of its sub-accesses might be, which is exactly what
happens in the PR.
Bootstrapped and tested on x86_64-linux. OK for trunk?
Thanks,
Martin
2017-10-02 Martin Jambor <mjambor@suse.cz>
PR tree-optimization/82363
* tree-sra.c (propagate_subaccesses_across_link): In unrecoverable
mismatch, mark lacc written regardless of racc.
testsuite/
* gcc.dg/tree-ssa/pr82363.c: New test.
---
gcc/testsuite/gcc.dg/tree-ssa/pr82363.c | 50 +++++++++++++++++++++++++++++++++
gcc/tree-sra.c | 2 +-
2 files changed, 51 insertions(+), 1 deletion(-)
create mode 100644 gcc/testsuite/gcc.dg/tree-ssa/pr82363.c
diff --git a/gcc/testsuite/gcc.dg/tree-ssa/pr82363.c b/gcc/testsuite/gcc.dg/tree-ssa/pr82363.c
new file mode 100644
index 00000000000..6652468976b
--- /dev/null
+++ b/gcc/testsuite/gcc.dg/tree-ssa/pr82363.c
@@ -0,0 +1,50 @@
+/* { dg-do run } */
+/* { dg-options "-O" } */
+
+struct A
+{
+ int b;
+ int c;
+ int d;
+};
+
+struct E
+{
+ int f;
+ int g:18;
+ struct A h;
+};
+
+struct I
+{
+ int b;
+ int j;
+ struct E k;
+};
+
+int l, *m = &l;
+
+struct A n;
+struct I o;
+
+void __attribute__ ((noipa))
+test_l (void)
+{
+ if (l != 1)
+ __builtin_abort ();
+}
+
+int main ()
+{
+ while (1)
+ {
+ struct I q = { 0, 0, {0, 0, {1, 1, 1}}}, p = q, r = p, *s = &q;
+ if (p.k.h.c)
+ o = p;
+ *m = r.k.h.d;
+ n = (*s).k.h;
+ break;
+ }
+ test_l ();
+ return 0;
+}
diff --git a/gcc/tree-sra.c b/gcc/tree-sra.c
index f5675edc7f1..bac593951e7 100644
--- a/gcc/tree-sra.c
+++ b/gcc/tree-sra.c
@@ -2691,7 +2691,7 @@ propagate_subaccesses_across_link (struct access *lacc, struct access *racc)
}
else
{
- if (rchild->grp_write && !lacc->grp_write)
+ if (!lacc->grp_write)
{
ret = true;
subtree_mark_written_and_enqueue (lacc);
--
2.14.1