testsuite: Add testcase for latent PR [PR123048]

This testcase started to be miscompiled with r16-4186 and went latent
again r16-6651.

2026-02-17  Jakub Jelinek  <jakub@redhat.com>

	PR rtl-optimization/123048
	* gcc.dg/pr123048.c: New test.

diff --git a/gcc/testsuite/gcc.dg/pr123048.c b/gcc/testsuite/gcc.dg/pr123048.c
new file mode 100644 (file)
index 0000000..4c9f584
--- /dev/null
+++ b/gcc/testsuite/gcc.dg/pr123048.c
@@ -0,0 +1,76 @@
+/* PR rtl-optimization/123048 */
+/* { dg-do run { target int32 } } */
+/* { dg-options "-O3 -fschedule-insns" } */
+/* { dg-require-effective-target scheduling } */
+
+int a[] = {
+  4, 7, 5, 5, 54, 2044508324, 0, 4, 7, 4049, 8, 6, 4089016648, 4, 50548861, 3,
+  107580753, 9, 2, 6, 7, 5, 5, 7, 7073096, 6, 2, 2, 1006888145, 607687, 101629,
+  3, 901097722, 9000684, 6, 8065728, 1, 1, 705015759, 5, 0, 6, 4, 104598, 3, 1,
+  5, 3099436303, 4, 4, 30930, 70347812, 7, 5, -1810856918, 907459465, 5, 3,
+  904427059, 2013776290, 6, 4, 0, 3, 3, 9, 7, 802195444, 6, 8001368,
+  4066508878, 70925, 3092731, 5, 706088902, 4, 2, 2, 1, 7, 3, 5, 303535960, 6,
+  7007092, 9037538, 70817, 1, 3, 4079995, 6, 6, 909243462, 6, 7, 7, 1,
+  708648649, 8, 6, 6048, 4, 909, 5, 10523913, 5, 4, 702138776, 0, 2, 504918807,
+  3, 3082640443, 9, 4, 6, 7068, 10842, 1, 70997, 3, 0, 4, 0, 2053790376, 90386,
+  2, 2050814, 5, 5, 0, 6, 2, 708143, 5, 3, 7, 604390888, 8, 2, 6, 5, 60999,
+  1068828381, 9, 0, 8, 906185462, 1090812512, 3, 9, 5, 1, 4, 60834842, 8085408,
+  6, 109, 8078467, 3, 400815, 2, 608, 4, 6, 5, 3, 1, 607071920, 0, 2, 40735498,
+  5, 1, 3087877, 908371, 4, 803740692, 2075208622, 2, 3, 90285, 2094854071, 1,
+  2029012, 0, 2, 0, 1, 5, 1, 7, 4, 200368, 4, 405801727, 5, 5, 1, 5067896,
+  608007406, 308918612, 8, 808555105
+};
+int c, d, e, k, j[3] = { 1, 2 }, *l;
+unsigned h;
+
+int
+foo (int o, unsigned p)
+{
+  return o >> 8 ^ a[(o ^ p) & 255];
+}
+
+int
+bar (int o, int p)
+{
+  d = (o >> 8 & 16777215) ^ a[(o ^ p) & 255];
+  o = d;
+  o = foo (o, p >> 8 & 255);
+  o = foo (o, p >> 6);
+  c = o >> 8 ^ a[(o ^ 24) & 255];
+  return c;
+}
+
+int
+baz (int o, int p, int r[], int s)
+{
+  unsigned b = -1;
+  int m, f;
+  m = -1 - o;
+  if (m + e)
+    goto lab;
+  do
+    {
+      while (k)
+       ;
+      for (int i = 0; i < 6; ++i)
+       h = bar (h, l[i]);
+    }
+  while (o);
+lab:
+  f = -(1 % r[1]);
+  m = 1 / s;
+  int a[] = { o, p, r[0], r[1], r[2], f, m, s };
+  for (int i = 0; i < 8; i++)
+    b = bar (b, a[i]);
+  return b;
+}
+
+int
+main ()
+{
+  if (__CHAR_BIT__ != 8 || sizeof (int) != 4)
+    return 0;
+  int g = baz (-5, 1, j, 2);
+  if (g != 4639)
+    __builtin_abort ();
+}