7123926: Some CTW test crash: !_control.contains(ctrl)
Summary: Don't eliminate Integer::toString() call node during String concatenation optimization if it has several uses.
Reviewed-by: twisti
--- a/hotspot/src/share/vm/opto/stringopts.cpp Thu Jul 12 00:39:53 2012 -0700
+++ b/hotspot/src/share/vm/opto/stringopts.cpp Fri Jul 13 17:48:26 2012 -0700
@@ -533,7 +533,17 @@
if (arg->is_Proj() && arg->in(0)->is_CallStaticJava()) {
CallStaticJavaNode* csj = arg->in(0)->as_CallStaticJava();
if (csj->method() != NULL &&
- csj->method()->intrinsic_id() == vmIntrinsics::_Integer_toString) {
+ csj->method()->intrinsic_id() == vmIntrinsics::_Integer_toString &&
+ arg->outcnt() == 1) {
+ // _control is the list of StringBuilder calls nodes which
+ // will be replaced by new String code after this optimization.
+ // Integer::toString() call is not part of StringBuilder calls
+ // chain. It could be eliminated only if its result is used
+ // only by this SB calls chain.
+ // Another limitation: it should be used only once because
+ // it is unknown that it is used only by this SB calls chain
+ // until all related SB calls nodes are collected.
+ assert(arg->unique_out() == cnode, "sanity");
sc->add_control(csj);
sc->push_int(csj->in(TypeFunc::Parms));
continue;