Hi,
The root cause of PR111355 and PR111482 is missing to check if vr0
is undefined_p before call vr0.lower_bound.
In the pattern "(X + C) / N",
(if (INTEGRAL_TYPE_P (type)
&& get_range_query (cfun)->range_of_expr (vr0, @0))
(if (...)
(plus (op @0 @2) { wide_int_to_tree (type, plus_op1 (c)); })
(if (TYPE_UNSIGNED (type) && c.sign_mask () < 0 ...
&& wi::geu_p (vr0.lower_bound (), -c))
In "(if (...)", there is code to prevent vr0's undefined_p,
But in the "else" part, vr0's undefined_p is not checked before
"wi::geu_p (vr0.lower_bound (), -c)".
Bootstrap & regtest pass on ppc64{,le}.
Is this ok for trunk?
BR,
Jeff (Jiufu Guo)
PR tree-optimization/111355
gcc/ChangeLog:
* match.pd ((X + C) / N): Update pattern.
gcc/testsuite/ChangeLog:
* gcc.dg/pr111355.c: New test.
---
gcc/match.pd | 2 +-
gcc/testsuite/gcc.dg/pr111355.c | 8 ++++++++
2 files changed, 9 insertions(+), 1 deletion(-)
create mode 100644 gcc/testsuite/gcc.dg/pr111355.c
diff --git a/gcc/match.pd b/gcc/match.pd
index 39c9c81966a..5fdfba14d47 100644
--- a/gcc/match.pd
+++ b/gcc/match.pd
@@ -1033,7 +1033,7 @@ DEFINE_INT_AND_FLOAT_ROUND_FN (RINT)
|| (vr0.nonnegative_p () && vr3.nonnegative_p ())
|| (vr0.nonpositive_p () && vr3.nonpositive_p ())))
(plus (op @0 @2) { wide_int_to_tree (type, plus_op1 (c)); })
- (if (TYPE_UNSIGNED (type) && c.sign_mask () < 0
+ (if (!vr0.undefined_p () && TYPE_UNSIGNED (type) && c.sign_mask () < 0
&& exact_mod (-c)
/* unsigned "X-(-C)" doesn't underflow. */
&& wi::geu_p (vr0.lower_bound (), -c))
diff --git a/gcc/testsuite/gcc.dg/pr111355.c b/gcc/testsuite/gcc.dg/pr111355.c
new file mode 100644
index 00000000000..8bacbc69d31
--- /dev/null
+++ b/gcc/testsuite/gcc.dg/pr111355.c
@@ -0,0 +1,8 @@
+/* { dg-do compile } */
+/* { dg-options "-O3 -Wno-div-by-zero" } */
+
+/* Make sure no ICE. */
+int main() {
+ unsigned b;
+ return b ? 1 << --b / 0 : 0;
+}
--
2.25.1
