Hi!
The wide-int.h templates expect that when an int/long etc. operand is used
it will be sign-extended based on the types precision.
wi_fold_in_parts passes 3 such non-zero constants to wi::lt_p, wi::gt_p
and wi::eq_p - 1, 3 and 4, which means it was doing weird things if either
some of 1, 3 or 4 weren't representable in type, or if type was unsigned 3 bit
type 4 should be written as -4.
The following patch promotes the subtraction operands to widest_int and
uses that as the type for ?h_range variables and compares them as such.
We don't need the overflow handling because there is never an overflow.
Bootstrapped/regtested on x86_64-linux and i686-linux (on the former also
with lto bootstrap), ok for trunk?
2022-02-02 Jakub Jelinek <ja...@redhat.com>
PR tree-optimization/104334
* range-op.cc (range_operator::wi_fold_in_parts): Change lh_range
and rh_range type to widest_int and subtract in widest_int. Remove
ov_rh, ov_lh and sign vars, always perform comparisons as signed
and use >, < and == operators for it.
* g++.dg/opt/pr104334.C: New test.
--- gcc/range-op.cc.jj 2022-01-13 22:29:15.345831749 +0100
+++ gcc/range-op.cc 2022-02-02 20:20:22.020000000 +0100
@@ -144,22 +144,21 @@ range_operator::wi_fold_in_parts (irange
const wide_int &rh_lb,
const wide_int &rh_ub) const
{
- wi::overflow_type ov_rh, ov_lh;
int_range_max tmp;
- wide_int rh_range = wi::sub (rh_ub, rh_lb, TYPE_SIGN (type), &ov_rh);
- wide_int lh_range = wi::sub (lh_ub, lh_lb, TYPE_SIGN (type), &ov_lh);
- signop sign = TYPE_SIGN (type);;
+ widest_int rh_range = wi::sub (widest_int::from (rh_ub, TYPE_SIGN (type)),
+ widest_int::from (rh_lb, TYPE_SIGN (type)));
+ widest_int lh_range = wi::sub (widest_int::from (lh_ub, TYPE_SIGN (type)),
+ widest_int::from (lh_lb, TYPE_SIGN (type)));
// If there are 2, 3, or 4 values in the RH range, do them separately.
// Call wi_fold_in_parts to check the RH side.
- if (wi::gt_p (rh_range, 0, sign) && wi::lt_p (rh_range, 4, sign)
- && ov_rh == wi::OVF_NONE)
+ if (rh_range > 0 && rh_range < 4)
{
wi_fold_in_parts (r, type, lh_lb, lh_ub, rh_lb, rh_lb);
- if (wi::gt_p (rh_range, 1, sign))
+ if (rh_range > 1)
{
wi_fold_in_parts (tmp, type, lh_lb, lh_ub, rh_lb + 1, rh_lb + 1);
r.union_ (tmp);
- if (wi::eq_p (rh_range, 3))
+ if (rh_range == 3)
{
wi_fold_in_parts (tmp, type, lh_lb, lh_ub, rh_lb + 2, rh_lb + 2);
r.union_ (tmp);
@@ -170,15 +169,14 @@ range_operator::wi_fold_in_parts (irange
}
// Otherise check for 2, 3, or 4 values in the LH range and split them up.
// The RH side has been checked, so no recursion needed.
- else if (wi::gt_p (lh_range, 0, sign) && wi::lt_p (lh_range, 4, sign)
- && ov_lh == wi::OVF_NONE)
+ else if (lh_range > 0 && lh_range < 4)
{
wi_fold (r, type, lh_lb, lh_lb, rh_lb, rh_ub);
- if (wi::gt_p (lh_range, 1, sign))
+ if (lh_range > 1)
{
wi_fold (tmp, type, lh_lb + 1, lh_lb + 1, rh_lb, rh_ub);
r.union_ (tmp);
- if (wi::eq_p (lh_range, 3))
+ if (lh_range == 3)
{
wi_fold (tmp, type, lh_lb + 2, lh_lb + 2, rh_lb, rh_ub);
r.union_ (tmp);
--- gcc/testsuite/g++.dg/opt/pr104334.C.jj 2022-02-02 14:35:51.184657968
+0100
+++ gcc/testsuite/g++.dg/opt/pr104334.C 2022-02-02 14:37:14.888478594 +0100
@@ -0,0 +1,40 @@
+// PR tree-optimization/104334
+// { dg-do run { target c++11 } }
+// { dg-options "-O2 --param logical-op-non-short-circuit=0" }
+
+enum class A { A0, A1, A2, A3 };
+int x;
+
+__attribute__((noipa)) void
+baz ()
+{
+ x = 1;
+}
+
+struct B {
+ unsigned b : 2;
+
+ A
+ foo () const
+ {
+ return static_cast<A> (b);
+ }
+
+ __attribute__((noinline)) void
+ bar ()
+ {
+ if (foo () == A::A2 || foo () == A::A3)
+ baz ();
+ }
+};
+
+int
+main ()
+{
+ B c;
+ c.b = 2;
+ c.bar ();
+ if (x != 1)
+ __builtin_abort ();
+ return 0;
+}
Jakub
