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