commit 1f02961b23976d35b10e2399708c6eb00632f9d6
Author: Andrew MacLeod <amacleod@redhat.com>
Date:   Fri Mar 24 09:18:33 2023 -0400

    Don't interpret contents of a value_relation record.
    
    before floating point relations were added, we tried to sanitize
    value-relation records to not include non-sensensical records... ie
    x != x or x < x.   INstead, we made a VREL_VARYING record with no
    operands.
    
    When floating point relations were supported, some of these were no
    longer non-sensical, AND we expanded the use of value_relation records
    into GORI.
    
    As a result, this sanitization is no longer needed.  The Oracle
    does not create records with op1 == op2, so its only within GORI
    that these records can exist, and we shouldnt try to interpret them.
    
    The bug occurs because the "sanitized" records doesnt set op1 anmd op2,
    but we have a record so expected it to be set.
    
            PR tree-optimization/109265
            PR tree-optimization/109274
            gcc/
            * value-relation.h (value_relation::set_relation): Always create the
            record that is requested.
    
            gcc/testsuite/
            * gcc.dg/pr109274.c: New.

diff --git a/gcc/testsuite/gcc.dg/pr109274.c b/gcc/testsuite/gcc.dg/pr109274.c
new file mode 100644
index 00000000000..5dbc0232f8e
--- /dev/null
+++ b/gcc/testsuite/gcc.dg/pr109274.c
@@ -0,0 +1,16 @@
+/* PR tree-optimization/109274 */
+/* { dg-do compile } */
+/* { dg-options "-O2 " } */
+
+float a, b, c;
+int d;
+float bar (void);
+
+void
+foo (void)
+{
+  a = 0 * -(2.0f * c);
+  d = a != a ? 0 : bar ();
+  b = c;
+}
+
diff --git a/gcc/value-relation.h b/gcc/value-relation.h
index 36a75862cc7..3177ecb1ad0 100644
--- a/gcc/value-relation.h
+++ b/gcc/value-relation.h
@@ -445,13 +445,6 @@ value_relation::set_relation (relation_kind r, tree n1, tree n2)
 {
   gcc_checking_assert (TREE_CODE (n1) == SSA_NAME
 		       && TREE_CODE (n2) == SSA_NAME);
-  if (n1 == n2 && r != VREL_EQ)
-    {
-      related = VREL_VARYING;
-      name1 = NULL_TREE;
-      name2 = NULL_TREE;
-      return;
-    }
   related = r;
   name1 = n1;
   name2 = n2;