8179070: nashorn+octane's box2d causes c2 to crash with "Bad graph detected in compute_lca_of_uses"
Summary: ciTypeFlow speculates field is null but parsing uses non null constant because of concurrent class initialization
Reviewed-by: thartmann
--- a/hotspot/src/share/vm/opto/parse3.cpp Thu May 04 17:54:34 2017 +0000
+++ b/hotspot/src/share/vm/opto/parse3.cpp Tue Apr 25 09:37:24 2017 +0200
@@ -146,8 +146,16 @@
void Parse::do_get_xxx(Node* obj, ciField* field, bool is_field) {
+ BasicType bt = field->layout_type();
+
// Does this field have a constant value? If so, just push the value.
- if (field->is_constant()) {
+ if (field->is_constant() &&
+ // Keep consistent with types found by ciTypeFlow: for an
+ // unloaded field type, ciTypeFlow::StateVector::do_getstatic()
+ // speculates the field is null. The code in the rest of this
+ // method does the same. We must not bypass it and use a non
+ // null constant here.
+ (bt != T_OBJECT || field->type()->is_loaded())) {
// final or stable field
Node* con = make_constant_from_field(field, obj);
if (con != NULL) {
@@ -163,7 +171,6 @@
int offset = field->offset_in_bytes();
const TypePtr* adr_type = C->alias_type(field)->adr_type();
Node *adr = basic_plus_adr(obj, obj, offset);
- BasicType bt = field->layout_type();
// Build the resultant type of the load
const Type *type;