[PATCH] Add a missing return transforming atomic bit test and operations

[H.J. Lu via Gcc-patches]

When failing to transform equivalent, but slighly different cases of
atomic bit test and operations to their canonical forms, return
immediately.

gcc/

        PR middle-end/103268
        * tree-ssa-ccp.c (optimize_atomic_bit_test_and): Add a missing
        return.

gcc/testsuite/

        PR middle-end/103268
        * gcc.dg/pr103268-1.c: New test.
        * gcc.dg/pr103268-2.c: Likewise.
---
 gcc/testsuite/gcc.dg/pr103268-1.c | 10 ++++++++++
 gcc/testsuite/gcc.dg/pr103268-2.c | 12 ++++++++++++
 gcc/tree-ssa-ccp.c                |  2 ++
 3 files changed, 24 insertions(+)
 create mode 100644 gcc/testsuite/gcc.dg/pr103268-1.c
 create mode 100644 gcc/testsuite/gcc.dg/pr103268-2.c

diff --git a/gcc/testsuite/gcc.dg/pr103268-1.c 
b/gcc/testsuite/gcc.dg/pr103268-1.c
new file mode 100644
index 00000000000..6d583d55d6d
--- /dev/null
+++ b/gcc/testsuite/gcc.dg/pr103268-1.c
@@ -0,0 +1,10 @@
+/* { dg-do compile } */
+/* { dg-options "-O2" } */
+
+extern int si;
+long
+test_types (void)
+{
+  unsigned int u2 = __atomic_fetch_xor (&si, 0, 5);
+  return u2;
+}
diff --git a/gcc/testsuite/gcc.dg/pr103268-2.c 
b/gcc/testsuite/gcc.dg/pr103268-2.c
new file mode 100644
index 00000000000..12283bb43d9
--- /dev/null
+++ b/gcc/testsuite/gcc.dg/pr103268-2.c
@@ -0,0 +1,12 @@
+/* { dg-do compile } */
+/* { dg-options "-O2" } */
+ 
+extern long pscc_a_2_3;
+extern int pscc_a_1_4;
+
+void
+pscc (void)
+{
+  pscc_a_1_4 = __sync_fetch_and_and (&pscc_a_2_3, 1);
+}
+
diff --git a/gcc/tree-ssa-ccp.c b/gcc/tree-ssa-ccp.c
index 0666dc652d0..18d57729d8a 100644
--- a/gcc/tree-ssa-ccp.c
+++ b/gcc/tree-ssa-ccp.c
@@ -3638,6 +3638,8 @@ optimize_atomic_bit_test_and (gimple_stmt_iterator *gsip,
              use_stmt = use_nop_stmt;
            }
        }
+      else
+       return;
 
       if (!bit)
        {
-- 
2.33.1