[PATCH] Fix get_maxval_strlen for COND_EXPR after changing them to ternary

[Andrew Pinski]

When COND_EXPR was changed from GIMPLE_SINGLE_RHS to
GIMPLE_TERNARY_RHS, get_maxval_strlen was not updated for that
changed.  With a patch which has a late PHIOPT produce COND_EXPR, I
saw a couple of regressions (pr23484-chk.c and  strncpy-chk.c).

This patch fixes get_maxval_strlen for that change.

OK for the trunk and 4.7 branch?  Bootstrapped and tested on
x86_64-linux-gnu with no regressions.  And in 4.7.0 with the patch for
PHIOPT producing COND_EXPR on both x86_64-linux-gnu and mipsisa64-elf.

Thanks,
Andrew Pinski

ChangeLog:
* gimple-fold.c (get_maxval_strlen): Move COND_EXPR handling under
GIMPLE_ASSIGN.

Index: gimple-fold.c
===================================================================
--- gimple-fold.c       (revision 187579)
+++ gimple-fold.c       (working copy)
@@ -670,13 +670,10 @@ get_maxval_strlen (tree arg, tree *lengt
 
   if (TREE_CODE (arg) != SSA_NAME)
     {
-      if (TREE_CODE (arg) == COND_EXPR)
-        return get_maxval_strlen (COND_EXPR_THEN (arg), length, visited, type)
-               && get_maxval_strlen (COND_EXPR_ELSE (arg), length, visited, 
type);
       /* We can end up with &(*iftmp_1)[0] here as well, so handle it.  */
-      else if (TREE_CODE (arg) == ADDR_EXPR
-              && TREE_CODE (TREE_OPERAND (arg, 0)) == ARRAY_REF
-              && integer_zerop (TREE_OPERAND (TREE_OPERAND (arg, 0), 1)))
+      if (TREE_CODE (arg) == ADDR_EXPR
+         && TREE_CODE (TREE_OPERAND (arg, 0)) == ARRAY_REF
+         && integer_zerop (TREE_OPERAND (TREE_OPERAND (arg, 0), 1)))
        {
          tree aop0 = TREE_OPERAND (TREE_OPERAND (arg, 0), 0);
          if (TREE_CODE (aop0) == INDIRECT_REF
@@ -736,6 +733,13 @@ get_maxval_strlen (tree arg, tree *lengt
             tree rhs = gimple_assign_rhs1 (def_stmt);
             return get_maxval_strlen (rhs, length, visited, type);
           }
+        else if (gimple_assign_rhs_code (def_stmt) == COND_EXPR)
+          {
+           tree op2 = gimple_assign_rhs2 (def_stmt);
+           tree op3 = gimple_assign_rhs3 (def_stmt);
+            return get_maxval_strlen (op2, length, visited, type)
+                   && get_maxval_strlen (op3, length, visited, type);
+          }
         return false;
 
       case GIMPLE_PHI: