Re: [PATCH] Fix incorrect subreg mode check [PR117476]

[Alexey Merzlyakov]

Updated testsuite/ChangeLog with respect to the original testcase author

-- >8 --

gcc/ChangeLog:

        * simplify-rtx.cc (simplify_context::simplify_unary_operation_1):
        Fix subreg mode check during zero_extend(not) -> xor optimization.

gcc/testsuite/ChangeLog:

        * gcc.dg/pr117476.c: New test. From Zhendong Su.

Signed-off-by: Alexey Merzlyakov <alexey.merzlya...@samsung.com>
---
 gcc/simplify-rtx.cc             |  2 +-
 gcc/testsuite/gcc.dg/pr117476.c | 12 ++++++++++++
 2 files changed, 13 insertions(+), 1 deletion(-)
 create mode 100644 gcc/testsuite/gcc.dg/pr117476.c

diff --git a/gcc/simplify-rtx.cc b/gcc/simplify-rtx.cc
index d05efac20dc..2a9cabaad09 100644
--- a/gcc/simplify-rtx.cc
+++ b/gcc/simplify-rtx.cc
@@ -1856,7 +1856,7 @@ simplify_context::simplify_unary_operation_1 (rtx_code 
code, machine_mode mode,
          && subreg_lowpart_p (op)
          && GET_MODE_SIZE (GET_MODE (op)).is_constant ()
          && (nonzero_bits (XEXP (XEXP (op, 0), 0), mode)
-             & ~GET_MODE_MASK (mode)) == 0)
+             & ~GET_MODE_MASK (GET_MODE (op))) == 0)
       {
        const uint64_t mask = GET_MODE_MASK (GET_MODE (op));
        return simplify_gen_binary (XOR, mode,
diff --git a/gcc/testsuite/gcc.dg/pr117476.c b/gcc/testsuite/gcc.dg/pr117476.c
new file mode 100644
index 00000000000..b8f51e697bf
--- /dev/null
+++ b/gcc/testsuite/gcc.dg/pr117476.c
@@ -0,0 +1,12 @@
+/* PR rtl-optimization/117476 */
+/* { dg-do run } */
+/* { dg-options "-O1" } */
+
+int c = 0x1FF;
+
+int main()
+{
+  if (((c ^ 0xFF) & 0xFF) != 0)
+    __builtin_abort();
+  return 0;
+}
-- 
2.34.1