1.1 --- a/src/share/vm/opto/escape.cpp Fri Dec 20 10:31:14 2013 +0100
1.2 +++ b/src/share/vm/opto/escape.cpp Thu Dec 26 21:00:23 2013 -0800
1.3 @@ -1579,9 +1579,20 @@
1.4 jobj->set_scalar_replaceable(false);
1.5 return;
1.6 }
1.7 + // 2. An object is not scalar replaceable if the field into which it is
1.8 + // stored has multiple bases one of which is null.
1.9 + if (field->base_count() > 1) {
1.10 + for (BaseIterator i(field); i.has_next(); i.next()) {
1.11 + PointsToNode* base = i.get();
1.12 + if (base == null_obj) {
1.13 + jobj->set_scalar_replaceable(false);
1.14 + return;
1.15 + }
1.16 + }
1.17 + }
1.18 }
1.19 assert(use->is_Field() || use->is_LocalVar(), "sanity");
1.20 - // 2. An object is not scalar replaceable if it is merged with other objects.
1.21 + // 3. An object is not scalar replaceable if it is merged with other objects.
1.22 for (EdgeIterator j(use); j.has_next(); j.next()) {
1.23 PointsToNode* ptn = j.get();
1.24 if (ptn->is_JavaObject() && ptn != jobj) {
1.25 @@ -1600,13 +1611,13 @@
1.26 FieldNode* field = j.get()->as_Field();
1.27 int offset = field->as_Field()->offset();
1.28
1.29 - // 3. An object is not scalar replaceable if it has a field with unknown
1.30 + // 4. An object is not scalar replaceable if it has a field with unknown
1.31 // offset (array's element is accessed in loop).
1.32 if (offset == Type::OffsetBot) {
1.33 jobj->set_scalar_replaceable(false);
1.34 return;
1.35 }
1.36 - // 4. Currently an object is not scalar replaceable if a LoadStore node
1.37 + // 5. Currently an object is not scalar replaceable if a LoadStore node
1.38 // access its field since the field value is unknown after it.
1.39 //
1.40 Node* n = field->ideal_node();
1.41 @@ -1617,7 +1628,7 @@
1.42 }
1.43 }
1.44
1.45 - // 5. Or the address may point to more then one object. This may produce
1.46 + // 6. Or the address may point to more then one object. This may produce
1.47 // the false positive result (set not scalar replaceable)
1.48 // since the flow-insensitive escape analysis can't separate
1.49 // the case when stores overwrite the field's value from the case
