[PATCH] Fix PR64764

[Richard Biener]

The following fixes PR64764.

Bootstrapped and tested on x86_64-unknown-linux-gnu, applied to trunk.

Richard.

2015-01-26  Richard Biener  <rguent...@suse.de>

        PR middle-end/64764
        * tree-ssa-uninit.c (is_pred_expr_subset_of): Handle
        combining two BIT_AND_EXPR predicates.

        * gcc.dg/uninit-19.c: New testcase.

Index: gcc/tree-ssa-uninit.c
===================================================================
--- gcc/tree-ssa-uninit.c       (revision 220107)
+++ gcc/tree-ssa-uninit.c       (working copy)
@@ -1377,7 +1377,8 @@ is_pred_expr_subset_of (pred_info expr1,
   if (expr2.invert)
     code2 = invert_tree_comparison (code2, false);
 
-  if (code1 == EQ_EXPR && code2 == BIT_AND_EXPR)
+  if ((code1 == EQ_EXPR || code1 == BIT_AND_EXPR)
+      && code2 == BIT_AND_EXPR)
     return wi::eq_p (expr1.pred_rhs,
                     wi::bit_and (expr1.pred_rhs, expr2.pred_rhs));
 
Index: gcc/testsuite/gcc.dg/uninit-19.c
===================================================================
--- gcc/testsuite/gcc.dg/uninit-19.c    (revision 0)
+++ gcc/testsuite/gcc.dg/uninit-19.c    (working copy)
@@ -0,0 +1,23 @@
+/* { dg-do compile } */
+/* { dg-options "-O -Wuninitialized" } */
+
+int a, l, m;
+float *b;
+float c, d, e, g, h;
+unsigned char i, k;
+void
+fn1 (int p1, float *f1, float *f2, float *f3, unsigned char *c1, float *f4,
+     unsigned char *c2, float *p10)
+{
+  if (p1 & 8)
+    b[3] = p10[a];  /* { dg-warning "may be used uninitialized" } */
+}
+
+void
+fn2 ()
+{
+  float *n;
+  if (l & 6)
+    n = &c + m;
+  fn1 (l, &d, &e, &g, &i, &h, &k, n);
+}