[PATCH, PR 64153] Check type sizes before V_C_Eing in evaluate_conditions_for_known_args

[Martin Jambor]

Hi,

apparently it is necessary to check that type sizes match before
attempting to fold-V_C_E them in evaluate_conditions_for_known_args.
So this patch does this.

It passes bootstrap and testing on x86_64-linux and I have verified
with a cross compiler that the reported bug is fixed (the generated
assembly is the same as before the commit which introduced the
problem).

OK for trunk and (after a bootstrap and testing there) the 4.9 branch?

Thanks,

Martin


2014-12-02  Martin Jambor  <mjam...@suse.cz>

        PR ipa/64153
        * ipa-inline-analysis.c (evaluate_conditions_for_known_args): Check
        type sizes before view_converting.

Index: src/gcc/ipa-inline-analysis.c
===================================================================
--- src.orig/gcc/ipa-inline-analysis.c
+++ src/gcc/ipa-inline-analysis.c
@@ -880,12 +880,19 @@ evaluate_conditions_for_known_args (stru
        }
       if (c->code == IS_NOT_CONSTANT || c->code == CHANGED)
        continue;
-      val = fold_unary (VIEW_CONVERT_EXPR, TREE_TYPE (c->val), val);
-      res = val
-       ? fold_binary_to_constant (c->code, boolean_type_node, val, c->val)
-       : NULL;
-      if (res && integer_zerop (res))
-       continue;
+
+      if (operand_equal_p (TYPE_SIZE (TREE_TYPE (c->val)),
+                          TYPE_SIZE (TREE_TYPE (val)), 0))
+       {
+         val = fold_unary (VIEW_CONVERT_EXPR, TREE_TYPE (c->val), val);
+
+         res = val
+           ? fold_binary_to_constant (c->code, boolean_type_node, val, c->val)
+           : NULL;
+
+         if (res && integer_zerop (res))
+           continue;
+       }
       clause |= 1 << (i + predicate_first_dynamic_condition);
     }
   return clause;