# HG changeset patch
# User kvn
# Date 1299351724 28800
# Node ID 8e72cd29b15d1df93d7b531cb25f1bb750d0baa3
# Parent  8ec5e1f45ea19e85e09437567e2ddc1650153a4e
6589823: Error: meet not symmetric
Summary: arrays pointers meet must fall to bottom if exact array klasses in upper lattice are not equal or super klass is exact.
Reviewed-by: never

diff -r 8ec5e1f45ea1 -r 8e72cd29b15d src/share/vm/opto/type.cpp
--- a/src/share/vm/opto/type.cpp	Fri Mar 04 22:44:50 2011 -0800
+++ b/src/share/vm/opto/type.cpp	Sat Mar 05 11:02:04 2011 -0800
@@ -3386,7 +3386,22 @@
         instance_id = InstanceBot;
         tary = TypeAry::make(Type::BOTTOM, tary->_size);
       }
+    } else // Non integral arrays.
+    // Must fall to bottom if exact klasses in upper lattice
+    // are not equal or super klass is exact.
+    if ( above_centerline(ptr) && klass() != tap->klass() &&
+         // meet with top[] and bottom[] are processed further down:
+         tap ->_klass != NULL  && this->_klass != NULL   &&
+         // both are exact and not equal:
+        ((tap ->_klass_is_exact && this->_klass_is_exact) ||
+         // 'tap'  is exact and super or unrelated:
+         (tap ->_klass_is_exact && !tap->klass()->is_subtype_of(klass())) ||
+         // 'this' is exact and super or unrelated:
+         (this->_klass_is_exact && !klass()->is_subtype_of(tap->klass())))) {
+      tary = TypeAry::make(Type::BOTTOM, tary->_size);
+      return make( NotNull, NULL, tary, lazy_klass, false, off, InstanceBot );
     }
+
     bool xk = false;
     switch (tap->ptr()) {
     case AnyNull: