2005-11-08 James A. Morrison <phython@gcc.gnu.org>

	    Diego Novillo  <dnovillo@redhat.com>

	PR 23046
	* tree-vrp.c (register_edge_assert_for): Do not register
	always-false predicates.

testsuite/

	PR 23046
	* g++.dg/tree-ssa/pr23046.C: New test.

git-svn-id: svn+ssh://gcc.gnu.org/svn/gcc/trunk@106656 138bc75d-0d04-0410-961f-82ee72b054a4

diff --git a/gcc/ChangeLog b/gcc/ChangeLog
index 4f792d3..5d6bfe6 100644 (file)
--- a/gcc/ChangeLog
+++ b/gcc/ChangeLog
@@ -1,3 +1,10 @@
+2005-11-08  James A. Morrison  <phython@gcc.gnu.org>
+           Diego Novillo  <dnovillo@redhat.com>
+
+       PR 23046
+       * tree-vrp.c (register_edge_assert_for): Do not register
+       always-false predicates.
+

 2005-11-08  Devang Patel <dpatel@apple.com>
 
        PR tree-optimization/23115
 2005-11-08  Devang Patel <dpatel@apple.com>
 
        PR tree-optimization/23115

diff --git a/gcc/testsuite/ChangeLog b/gcc/testsuite/ChangeLog
index 6ea0741..6444335 100644 (file)
--- a/gcc/testsuite/ChangeLog
+++ b/gcc/testsuite/ChangeLog
@@ -1,3 +1,8 @@
+2005-11-08  Diego Novillo  <dnovillo@redhat.com>
+
+       PR 23046
+       * g++.dg/tree-ssa/pr23046.C: New test.
+

 2005-11-08  Devang Patel <dpatel@apple.com>
 
        PR tree-optimization/23115
 2005-11-08  Devang Patel <dpatel@apple.com>
 
        PR tree-optimization/23115

diff --git a/gcc/testsuite/g++.dg/tree-ssa/pr23046.C b/gcc/testsuite/g++.dg/tree-ssa/pr23046.C
new file mode 100644 (file)
index 0000000..eb8f395
--- /dev/null
+++ b/gcc/testsuite/g++.dg/tree-ssa/pr23046.C
@@ -0,0 +1,11 @@
+/* { dg-do compile } */
+/* { dg-options "-O2" } */
+
+enum eumtype { ENUM1, ENUM2 };
+void g(const eumtype kind );
+void f(long i);
+void g(const eumtype kind)
+{
+  if ((kind != ENUM1) && (kind != ENUM2))
+    f(kind);
+}

diff --git a/gcc/tree-vrp.c b/gcc/tree-vrp.c
index 929908b..d49c4d4 100644 (file)
--- a/gcc/tree-vrp.c
+++ b/gcc/tree-vrp.c
@@ -2504,6 +2504,24 @@ register_edge_assert_for (tree name, edge e, block_stmt_iterator si)
             need to invert the sign comparison.  */
          if (is_else_edge)
            comp_code = invert_tree_comparison (comp_code, 0);
             need to invert the sign comparison.  */
          if (is_else_edge)
            comp_code = invert_tree_comparison (comp_code, 0);

+
+         /* Do not register always-false predicates.  FIXME, this
+            works around a limitation in fold() when dealing with
+            enumerations.  Given 'enum { N1, N2 } x;', fold will not
+            fold 'if (x > N2)' to 'if (0)'.  */
+         if ((comp_code == GT_EXPR || comp_code == LT_EXPR)
+             && (INTEGRAL_TYPE_P (TREE_TYPE (val))
+                 || SCALAR_FLOAT_TYPE_P (TREE_TYPE (val))))
+           {
+             tree min = TYPE_MIN_VALUE (TREE_TYPE (val));
+             tree max = TYPE_MAX_VALUE (TREE_TYPE (val));
+
+             if (comp_code == GT_EXPR && compare_values (val, max) == 0)
+               return false;
+
+             if (comp_code == LT_EXPR && compare_values (val, min) == 0)
+               return false;
+           }

        }
     }
   else
        }
     }
   else