[gcc(refs/users/aoliva/heads/testme)] [ifcombine] fix mask variable test to match use [PR118344]

[Alexandre Oliva via Gcc-cvs]

https://gcc.gnu.org/g:adbdc5d3f1f3d9d13f809c8c9f02f9514d2e65dc

commit adbdc5d3f1f3d9d13f809c8c9f02f9514d2e65dc
Author: Alexandre Oliva <ol...@adacore.com>
Date:   Thu Jan 9 10:23:50 2025 -0300

    [ifcombine] fix mask variable test to match use [PR118344]
    
    There was a cut&pasto in the rr_and_mask's adjustment to match the
    combined type: the test on whether there was a mask already was
    testing the wrong variable, and then it might crash or otherwise fail
    accessing an undefined mask.  This only hit with checking enabled,
    and rarely at that.
    
    
    for  gcc/ChangeLog
    
            PR tree-optimization/118344
            * gimple-fold.cc (fold_truth_andor_for_ifcombine): Fix typo in
            rr_and_mask's type adjustment test.
    
    for  gcc/testsuite/ChangeLog
    
            PR tree-optimization/118344
            * gcc.dg/field-merge-19.c: New.

Diff:
---
 gcc/testsuite/gcc.dg/field-merge-19.c | 41 +++++++++++++++++++++++++++++++++++
 1 file changed, 41 insertions(+)

diff --git a/gcc/testsuite/gcc.dg/field-merge-19.c 
b/gcc/testsuite/gcc.dg/field-merge-19.c
new file mode 100644
index 000000000000..5622baa52b0a
--- /dev/null
+++ b/gcc/testsuite/gcc.dg/field-merge-19.c
@@ -0,0 +1,41 @@
+/* { dg-do compile } */
+/* { dg-options "-O3 -fchecking" } */
+
+/* PR tree-optimization/118344 */
+
+/* This used to ICE attempting to extend a mask variable after testing the
+   wrong mask variable.  */
+
+int d, e, g, h, i, c, j;
+static short k;
+char o;
+static int *p;
+static long *a;
+int b[0];
+int q(int s, int t, int *u, int *v) {
+  for (int f = 0; f < s; f++)
+    if ((t & v[f]) != u[f])
+      return 0;
+  return 1;
+}
+int w(int s, int t) {
+  int l[] = {t, t, t, t}, m[] = {e, e, 3, 1};
+  int n = q(s, d, l, m);
+  return n;
+}
+int x(unsigned s) {
+  unsigned r;
+  if (s >= -1)
+    return 1;
+  r = 10000000;
+  while (s > 1 / r)
+    r /= 2;
+  return g ? 2 : 0;
+}
+void y() {
+  for (;;) {
+    b[w(8, *p)] = h;
+    for (; a + k; j = o)
+      i &= c = x(6) < 0;
+  }
+}