tree-optimization/105802 - another unswitching type issue

This also fixes the type of the irange used for unswitching of
switch statements.

	PR tree-optimization/105802
	* tree-ssa-loop-unswitch.cc (find_unswitching_predicates_for_bb):
	Make sure to also compute the range in the type of the switch index.

	* g++.dg/opt/pr105802.C: New testcase.

diff --git a/gcc/testsuite/g++.dg/opt/pr105802.C b/gcc/testsuite/g++.dg/opt/pr105802.C
new file mode 100644 (file)
index 0000000..2514245
--- /dev/null
+++ b/gcc/testsuite/g++.dg/opt/pr105802.C
@@ -0,0 +1,23 @@
+// { dg-do compile }
+// { dg-options "-O3" }
+
+enum E { E0, E1 };
+
+void bar ();
+void baz ();
+
+int c;
+
+void
+foo (int i)
+{
+  E e = (E) i;
+  while (c)
+    switch (e)
+      {
+      case E0:
+        bar ();
+      case E1:
+        baz ();
+      }
+}

diff --git a/gcc/tree-ssa-loop-unswitch.cc b/gcc/tree-ssa-loop-unswitch.cc
index 2b6013e..61c04ed 100644 (file)
--- a/gcc/tree-ssa-loop-unswitch.cc
+++ b/gcc/tree-ssa-loop-unswitch.cc
@@ -523,22 +523,19 @@ find_unswitching_predicates_for_bb (basic_block bb, class loop *loop,
          tree lab = gimple_switch_label (stmt, i);
          tree cmp;
          int_range<2> lab_range;
+         tree low = fold_convert (idx_type, CASE_LOW (lab));
          if (CASE_HIGH (lab) != NULL_TREE)
            {
-             tree cmp1 = fold_build2 (GE_EXPR, boolean_type_node, idx,
-                                      fold_convert (idx_type,
-                                                    CASE_LOW (lab)));
-             tree cmp2 = fold_build2 (LE_EXPR, boolean_type_node, idx,
-                                      fold_convert (idx_type,
-                                                    CASE_HIGH (lab)));
+             tree high = fold_convert (idx_type, CASE_HIGH (lab));
+             tree cmp1 = fold_build2 (GE_EXPR, boolean_type_node, idx, low);
+             tree cmp2 = fold_build2 (LE_EXPR, boolean_type_node, idx, high);
              cmp = fold_build2 (BIT_AND_EXPR, boolean_type_node, cmp1, cmp2);
-             lab_range.set (CASE_LOW (lab), CASE_HIGH (lab));
+             lab_range.set (low, high);
            }
          else
            {
-             cmp = fold_build2 (EQ_EXPR, boolean_type_node, idx,
-                                fold_convert (idx_type, CASE_LOW (lab)));
-             lab_range.set (CASE_LOW (lab));
+             cmp = fold_build2 (EQ_EXPR, boolean_type_node, idx, low);
+             lab_range.set (low);
            }
 
          /* Combine the expression with the existing one.  */