2010-08-31 Richard Guenther <rguenther@suse.de>

[pf3gnuchains/gcc-fork.git] / gcc / gimple.c

diff --git a/gcc/gimple.c b/gcc/gimple.c
index 50b2eab..7433b14 100644 (file)
--- a/gcc/gimple.c
+++ b/gcc/gimple.c
@@ -4582,63 +4582,6 @@ gimple_get_alias_set (tree t)
       if (t1 != t)
        return get_alias_set (t1);
     }
-  else if (POINTER_TYPE_P (t))
-    {
-      /* From the common C and C++ langhook implementation:
-
-        Unfortunately, there is no canonical form of a pointer type.
-        In particular, if we have `typedef int I', then `int *', and
-        `I *' are different types.  So, we have to pick a canonical
-        representative.  We do this below.
-
-        Technically, this approach is actually more conservative that
-        it needs to be.  In particular, `const int *' and `int *'
-        should be in different alias sets, according to the C and C++
-        standard, since their types are not the same, and so,
-        technically, an `int **' and `const int **' cannot point at
-        the same thing.
-
-        But, the standard is wrong.  In particular, this code is
-        legal C++:
-
-        int *ip;
-        int **ipp = &ip;
-        const int* const* cipp = ipp;
-        And, it doesn't make sense for that to be legal unless you
-        can dereference IPP and CIPP.  So, we ignore cv-qualifiers on
-        the pointed-to types.  This issue has been reported to the
-        C++ committee.  */
-
-      /* In addition to the above canonicalization issue with LTO
-         we should also canonicalize `T (*)[]' to `T *' avoiding
-        alias issues with pointer-to element types and pointer-to
-        array types.
-
-        Likewise we need to deal with the situation of incomplete
-        pointed-to types and make `*(struct X **)&a' and
-        `*(struct X {} **)&a' alias.  Otherwise we will have to
-        guarantee that all pointer-to incomplete type variants
-        will be replaced by pointer-to complete type variants if
-        they are available.
-
-        With LTO the convenient situation of using `void *' to
-        access and store any pointer type will also become
-        more apparent (and `void *' is just another pointer-to
-        incomplete type).  Assigning alias-set zero to `void *'
-        and all pointer-to incomplete types is a not appealing
-        solution.  Assigning an effective alias-set zero only
-        affecting pointers might be - by recording proper subset
-        relationships of all pointer alias-sets.
-
-        Pointer-to function types are another grey area which
-        needs caution.  Globbing them all into one alias-set
-        or the above effective zero set would work.  */
-
-      /* For now just assign the same alias-set to all pointers.
-         That's simple and avoids all the above problems.  */
-      if (t != ptr_type_node)
-       return get_alias_set (ptr_type_node);
-    }
 
   return -1;
 }