+
+/* Canonicalize a tree T for use in a COND_EXPR as conditional. Returns
+ a canonicalized tree that is valid for a COND_EXPR or NULL_TREE, if
+ we failed to create one. */
+
+tree
+canonicalize_cond_expr_cond (tree t)
+{
+ /* For (bool)x use x != 0. */
+ if (TREE_CODE (t) == NOP_EXPR
+ && TREE_TYPE (t) == boolean_type_node)
+ {
+ tree top0 = TREE_OPERAND (t, 0);
+ t = build2 (NE_EXPR, TREE_TYPE (t),
+ top0, build_int_cst (TREE_TYPE (top0), 0));
+ }
+ /* For !x use x == 0. */
+ else if (TREE_CODE (t) == TRUTH_NOT_EXPR)
+ {
+ tree top0 = TREE_OPERAND (t, 0);
+ t = build2 (EQ_EXPR, TREE_TYPE (t),
+ top0, build_int_cst (TREE_TYPE (top0), 0));
+ }
+ /* For cmp ? 1 : 0 use cmp. */
+ else if (TREE_CODE (t) == COND_EXPR
+ && COMPARISON_CLASS_P (TREE_OPERAND (t, 0))
+ && integer_onep (TREE_OPERAND (t, 1))
+ && integer_zerop (TREE_OPERAND (t, 2)))
+ {
+ tree top0 = TREE_OPERAND (t, 0);
+ t = build2 (TREE_CODE (top0), TREE_TYPE (t),
+ TREE_OPERAND (top0, 0), TREE_OPERAND (top0, 1));
+ }
+
+ /* A valid conditional for a COND_EXPR is either a gimple value
+ or a comparison with two gimple value operands. */
+ if (is_gimple_val (t)
+ || (COMPARISON_CLASS_P (t)
+ && is_gimple_val (TREE_OPERAND (t, 0))
+ && is_gimple_val (TREE_OPERAND (t, 1))))
+ return t;
+
+ return NULL_TREE;
+}